7585 lines
207 KiB
C
7585 lines
207 KiB
C
/* Low level interface to ptrace, for the remote server for GDB.
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Copyright (C) 1995-2017 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "server.h"
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#include "linux-low.h"
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#include "nat/linux-osdata.h"
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#include "agent.h"
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#include "tdesc.h"
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#include "rsp-low.h"
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#include "signals-state-save-restore.h"
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#include "nat/linux-nat.h"
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#include "nat/linux-waitpid.h"
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#include "gdb_wait.h"
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#include "nat/gdb_ptrace.h"
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#include "nat/linux-ptrace.h"
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#include "nat/linux-procfs.h"
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#include "nat/linux-personality.h"
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#include <signal.h>
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#include <sys/ioctl.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include <sys/syscall.h>
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#include <sched.h>
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#include <ctype.h>
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#include <pwd.h>
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#include <sys/types.h>
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#include <dirent.h>
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#include <sys/stat.h>
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#include <sys/vfs.h>
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#include <sys/uio.h>
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#include "filestuff.h"
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#include "tracepoint.h"
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#include "hostio.h"
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#include <inttypes.h>
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#include "common-inferior.h"
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#include "nat/fork-inferior.h"
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#include "environ.h"
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#ifndef ELFMAG0
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/* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
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then ELFMAG0 will have been defined. If it didn't get included by
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gdb_proc_service.h then including it will likely introduce a duplicate
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definition of elf_fpregset_t. */
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#include <elf.h>
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#endif
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#include "nat/linux-namespaces.h"
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#ifndef SPUFS_MAGIC
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#define SPUFS_MAGIC 0x23c9b64e
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#endif
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#ifdef HAVE_PERSONALITY
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# include <sys/personality.h>
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# if !HAVE_DECL_ADDR_NO_RANDOMIZE
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# define ADDR_NO_RANDOMIZE 0x0040000
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# endif
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#endif
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#ifndef O_LARGEFILE
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#define O_LARGEFILE 0
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#endif
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/* Some targets did not define these ptrace constants from the start,
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so gdbserver defines them locally here. In the future, these may
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be removed after they are added to asm/ptrace.h. */
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#if !(defined(PT_TEXT_ADDR) \
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|| defined(PT_DATA_ADDR) \
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|| defined(PT_TEXT_END_ADDR))
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#if defined(__mcoldfire__)
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/* These are still undefined in 3.10 kernels. */
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#define PT_TEXT_ADDR 49*4
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#define PT_DATA_ADDR 50*4
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#define PT_TEXT_END_ADDR 51*4
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/* BFIN already defines these since at least 2.6.32 kernels. */
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#elif defined(BFIN)
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#define PT_TEXT_ADDR 220
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#define PT_TEXT_END_ADDR 224
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#define PT_DATA_ADDR 228
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/* These are still undefined in 3.10 kernels. */
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#elif defined(__TMS320C6X__)
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#define PT_TEXT_ADDR (0x10000*4)
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#define PT_DATA_ADDR (0x10004*4)
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#define PT_TEXT_END_ADDR (0x10008*4)
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#endif
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#endif
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#ifdef HAVE_LINUX_BTRACE
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# include "nat/linux-btrace.h"
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# include "btrace-common.h"
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#endif
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#ifndef HAVE_ELF32_AUXV_T
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/* Copied from glibc's elf.h. */
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typedef struct
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{
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uint32_t a_type; /* Entry type */
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union
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{
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uint32_t a_val; /* Integer value */
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/* We use to have pointer elements added here. We cannot do that,
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though, since it does not work when using 32-bit definitions
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on 64-bit platforms and vice versa. */
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} a_un;
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} Elf32_auxv_t;
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#endif
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#ifndef HAVE_ELF64_AUXV_T
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/* Copied from glibc's elf.h. */
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typedef struct
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{
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uint64_t a_type; /* Entry type */
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union
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{
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uint64_t a_val; /* Integer value */
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/* We use to have pointer elements added here. We cannot do that,
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though, since it does not work when using 32-bit definitions
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on 64-bit platforms and vice versa. */
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} a_un;
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} Elf64_auxv_t;
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#endif
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/* Does the current host support PTRACE_GETREGSET? */
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int have_ptrace_getregset = -1;
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/* LWP accessors. */
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/* See nat/linux-nat.h. */
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ptid_t
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ptid_of_lwp (struct lwp_info *lwp)
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{
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return ptid_of (get_lwp_thread (lwp));
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}
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/* See nat/linux-nat.h. */
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void
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lwp_set_arch_private_info (struct lwp_info *lwp,
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struct arch_lwp_info *info)
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{
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lwp->arch_private = info;
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}
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/* See nat/linux-nat.h. */
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struct arch_lwp_info *
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lwp_arch_private_info (struct lwp_info *lwp)
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{
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return lwp->arch_private;
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}
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/* See nat/linux-nat.h. */
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int
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lwp_is_stopped (struct lwp_info *lwp)
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{
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return lwp->stopped;
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}
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/* See nat/linux-nat.h. */
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enum target_stop_reason
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lwp_stop_reason (struct lwp_info *lwp)
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{
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return lwp->stop_reason;
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}
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/* See nat/linux-nat.h. */
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int
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lwp_is_stepping (struct lwp_info *lwp)
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{
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return lwp->stepping;
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}
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/* A list of all unknown processes which receive stop signals. Some
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other process will presumably claim each of these as forked
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children momentarily. */
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struct simple_pid_list
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{
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/* The process ID. */
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int pid;
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/* The status as reported by waitpid. */
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int status;
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/* Next in chain. */
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struct simple_pid_list *next;
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};
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struct simple_pid_list *stopped_pids;
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/* Trivial list manipulation functions to keep track of a list of new
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stopped processes. */
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static void
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add_to_pid_list (struct simple_pid_list **listp, int pid, int status)
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{
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struct simple_pid_list *new_pid = XNEW (struct simple_pid_list);
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new_pid->pid = pid;
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new_pid->status = status;
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new_pid->next = *listp;
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*listp = new_pid;
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}
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static int
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pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp)
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{
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struct simple_pid_list **p;
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for (p = listp; *p != NULL; p = &(*p)->next)
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if ((*p)->pid == pid)
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{
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struct simple_pid_list *next = (*p)->next;
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*statusp = (*p)->status;
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xfree (*p);
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*p = next;
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return 1;
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}
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return 0;
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}
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enum stopping_threads_kind
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{
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/* Not stopping threads presently. */
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NOT_STOPPING_THREADS,
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/* Stopping threads. */
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STOPPING_THREADS,
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/* Stopping and suspending threads. */
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STOPPING_AND_SUSPENDING_THREADS
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};
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/* This is set while stop_all_lwps is in effect. */
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enum stopping_threads_kind stopping_threads = NOT_STOPPING_THREADS;
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/* FIXME make into a target method? */
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int using_threads = 1;
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/* True if we're presently stabilizing threads (moving them out of
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jump pads). */
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static int stabilizing_threads;
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static void linux_resume_one_lwp (struct lwp_info *lwp,
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int step, int signal, siginfo_t *info);
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static void linux_resume (struct thread_resume *resume_info, size_t n);
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static void stop_all_lwps (int suspend, struct lwp_info *except);
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static void unstop_all_lwps (int unsuspend, struct lwp_info *except);
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static void unsuspend_all_lwps (struct lwp_info *except);
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static int linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
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int *wstat, int options);
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static int linux_wait_for_event (ptid_t ptid, int *wstat, int options);
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static struct lwp_info *add_lwp (ptid_t ptid);
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static void linux_mourn (struct process_info *process);
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static int linux_stopped_by_watchpoint (void);
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static void mark_lwp_dead (struct lwp_info *lwp, int wstat);
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static int lwp_is_marked_dead (struct lwp_info *lwp);
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static void proceed_all_lwps (void);
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static int finish_step_over (struct lwp_info *lwp);
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static int kill_lwp (unsigned long lwpid, int signo);
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static void enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info);
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static void complete_ongoing_step_over (void);
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static int linux_low_ptrace_options (int attached);
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static int check_ptrace_stopped_lwp_gone (struct lwp_info *lp);
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static void proceed_one_lwp (thread_info *thread, lwp_info *except);
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/* When the event-loop is doing a step-over, this points at the thread
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being stepped. */
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ptid_t step_over_bkpt;
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/* True if the low target can hardware single-step. */
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static int
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can_hardware_single_step (void)
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{
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if (the_low_target.supports_hardware_single_step != NULL)
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return the_low_target.supports_hardware_single_step ();
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else
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return 0;
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}
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/* True if the low target can software single-step. Such targets
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implement the GET_NEXT_PCS callback. */
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static int
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can_software_single_step (void)
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{
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return (the_low_target.get_next_pcs != NULL);
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}
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/* True if the low target supports memory breakpoints. If so, we'll
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have a GET_PC implementation. */
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static int
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supports_breakpoints (void)
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{
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return (the_low_target.get_pc != NULL);
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}
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/* Returns true if this target can support fast tracepoints. This
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does not mean that the in-process agent has been loaded in the
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inferior. */
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static int
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supports_fast_tracepoints (void)
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{
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return the_low_target.install_fast_tracepoint_jump_pad != NULL;
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}
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/* True if LWP is stopped in its stepping range. */
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static int
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lwp_in_step_range (struct lwp_info *lwp)
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{
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CORE_ADDR pc = lwp->stop_pc;
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return (pc >= lwp->step_range_start && pc < lwp->step_range_end);
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}
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struct pending_signals
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{
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int signal;
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siginfo_t info;
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struct pending_signals *prev;
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};
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/* The read/write ends of the pipe registered as waitable file in the
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event loop. */
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static int linux_event_pipe[2] = { -1, -1 };
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/* True if we're currently in async mode. */
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#define target_is_async_p() (linux_event_pipe[0] != -1)
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static void send_sigstop (struct lwp_info *lwp);
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static void wait_for_sigstop (void);
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/* Return non-zero if HEADER is a 64-bit ELF file. */
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static int
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elf_64_header_p (const Elf64_Ehdr *header, unsigned int *machine)
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{
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if (header->e_ident[EI_MAG0] == ELFMAG0
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&& header->e_ident[EI_MAG1] == ELFMAG1
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&& header->e_ident[EI_MAG2] == ELFMAG2
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&& header->e_ident[EI_MAG3] == ELFMAG3)
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{
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*machine = header->e_machine;
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return header->e_ident[EI_CLASS] == ELFCLASS64;
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}
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*machine = EM_NONE;
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return -1;
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}
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/* Return non-zero if FILE is a 64-bit ELF file,
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zero if the file is not a 64-bit ELF file,
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and -1 if the file is not accessible or doesn't exist. */
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static int
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elf_64_file_p (const char *file, unsigned int *machine)
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{
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Elf64_Ehdr header;
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int fd;
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fd = open (file, O_RDONLY);
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if (fd < 0)
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return -1;
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if (read (fd, &header, sizeof (header)) != sizeof (header))
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{
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close (fd);
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return 0;
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}
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close (fd);
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return elf_64_header_p (&header, machine);
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}
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/* Accepts an integer PID; Returns true if the executable PID is
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running is a 64-bit ELF file.. */
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int
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linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine)
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{
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char file[PATH_MAX];
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sprintf (file, "/proc/%d/exe", pid);
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return elf_64_file_p (file, machine);
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}
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static void
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delete_lwp (struct lwp_info *lwp)
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{
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struct thread_info *thr = get_lwp_thread (lwp);
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if (debug_threads)
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debug_printf ("deleting %ld\n", lwpid_of (thr));
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remove_thread (thr);
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if (the_low_target.delete_thread != NULL)
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the_low_target.delete_thread (lwp->arch_private);
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else
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gdb_assert (lwp->arch_private == NULL);
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free (lwp);
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}
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/* Add a process to the common process list, and set its private
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data. */
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static struct process_info *
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linux_add_process (int pid, int attached)
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{
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struct process_info *proc;
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proc = add_process (pid, attached);
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proc->priv = XCNEW (struct process_info_private);
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if (the_low_target.new_process != NULL)
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proc->priv->arch_private = the_low_target.new_process ();
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return proc;
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}
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static CORE_ADDR get_pc (struct lwp_info *lwp);
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/* Call the target arch_setup function on the current thread. */
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static void
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linux_arch_setup (void)
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{
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the_low_target.arch_setup ();
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}
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/* Call the target arch_setup function on THREAD. */
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static void
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linux_arch_setup_thread (struct thread_info *thread)
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{
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struct thread_info *saved_thread;
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saved_thread = current_thread;
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current_thread = thread;
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linux_arch_setup ();
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current_thread = saved_thread;
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}
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/* Handle a GNU/Linux extended wait response. If we see a clone,
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fork, or vfork event, we need to add the new LWP to our list
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(and return 0 so as not to report the trap to higher layers).
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If we see an exec event, we will modify ORIG_EVENT_LWP to point
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to a new LWP representing the new program. */
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static int
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handle_extended_wait (struct lwp_info **orig_event_lwp, int wstat)
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{
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struct lwp_info *event_lwp = *orig_event_lwp;
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int event = linux_ptrace_get_extended_event (wstat);
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struct thread_info *event_thr = get_lwp_thread (event_lwp);
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struct lwp_info *new_lwp;
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gdb_assert (event_lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE);
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/* All extended events we currently use are mid-syscall. Only
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PTRACE_EVENT_STOP is delivered more like a signal-stop, but
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you have to be using PTRACE_SEIZE to get that. */
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event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
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if ((event == PTRACE_EVENT_FORK) || (event == PTRACE_EVENT_VFORK)
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|| (event == PTRACE_EVENT_CLONE))
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{
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ptid_t ptid;
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unsigned long new_pid;
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int ret, status;
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/* Get the pid of the new lwp. */
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ptrace (PTRACE_GETEVENTMSG, lwpid_of (event_thr), (PTRACE_TYPE_ARG3) 0,
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&new_pid);
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/* If we haven't already seen the new PID stop, wait for it now. */
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if (!pull_pid_from_list (&stopped_pids, new_pid, &status))
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{
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/* The new child has a pending SIGSTOP. We can't affect it until it
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hits the SIGSTOP, but we're already attached. */
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ret = my_waitpid (new_pid, &status, __WALL);
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if (ret == -1)
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perror_with_name ("waiting for new child");
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else if (ret != new_pid)
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warning ("wait returned unexpected PID %d", ret);
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else if (!WIFSTOPPED (status))
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warning ("wait returned unexpected status 0x%x", status);
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}
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if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK)
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{
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struct process_info *parent_proc;
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struct process_info *child_proc;
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struct lwp_info *child_lwp;
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struct thread_info *child_thr;
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struct target_desc *tdesc;
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ptid = ptid_build (new_pid, new_pid, 0);
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|
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("HEW: Got fork event from LWP %ld, "
|
|
"new child is %d\n",
|
|
ptid_get_lwp (ptid_of (event_thr)),
|
|
ptid_get_pid (ptid));
|
|
}
|
|
|
|
/* Add the new process to the tables and clone the breakpoint
|
|
lists of the parent. We need to do this even if the new process
|
|
will be detached, since we will need the process object and the
|
|
breakpoints to remove any breakpoints from memory when we
|
|
detach, and the client side will access registers. */
|
|
child_proc = linux_add_process (new_pid, 0);
|
|
gdb_assert (child_proc != NULL);
|
|
child_lwp = add_lwp (ptid);
|
|
gdb_assert (child_lwp != NULL);
|
|
child_lwp->stopped = 1;
|
|
child_lwp->must_set_ptrace_flags = 1;
|
|
child_lwp->status_pending_p = 0;
|
|
child_thr = get_lwp_thread (child_lwp);
|
|
child_thr->last_resume_kind = resume_stop;
|
|
child_thr->last_status.kind = TARGET_WAITKIND_STOPPED;
|
|
|
|
/* If we're suspending all threads, leave this one suspended
|
|
too. If the fork/clone parent is stepping over a breakpoint,
|
|
all other threads have been suspended already. Leave the
|
|
child suspended too. */
|
|
if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS
|
|
|| event_lwp->bp_reinsert != 0)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("HEW: leaving child suspended\n");
|
|
child_lwp->suspended = 1;
|
|
}
|
|
|
|
parent_proc = get_thread_process (event_thr);
|
|
child_proc->attached = parent_proc->attached;
|
|
|
|
if (event_lwp->bp_reinsert != 0
|
|
&& can_software_single_step ()
|
|
&& event == PTRACE_EVENT_VFORK)
|
|
{
|
|
/* If we leave single-step breakpoints there, child will
|
|
hit it, so uninsert single-step breakpoints from parent
|
|
(and child). Once vfork child is done, reinsert
|
|
them back to parent. */
|
|
uninsert_single_step_breakpoints (event_thr);
|
|
}
|
|
|
|
clone_all_breakpoints (child_thr, event_thr);
|
|
|
|
tdesc = allocate_target_description ();
|
|
copy_target_description (tdesc, parent_proc->tdesc);
|
|
child_proc->tdesc = tdesc;
|
|
|
|
/* Clone arch-specific process data. */
|
|
if (the_low_target.new_fork != NULL)
|
|
the_low_target.new_fork (parent_proc, child_proc);
|
|
|
|
/* Save fork info in the parent thread. */
|
|
if (event == PTRACE_EVENT_FORK)
|
|
event_lwp->waitstatus.kind = TARGET_WAITKIND_FORKED;
|
|
else if (event == PTRACE_EVENT_VFORK)
|
|
event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORKED;
|
|
|
|
event_lwp->waitstatus.value.related_pid = ptid;
|
|
|
|
/* The status_pending field contains bits denoting the
|
|
extended event, so when the pending event is handled,
|
|
the handler will look at lwp->waitstatus. */
|
|
event_lwp->status_pending_p = 1;
|
|
event_lwp->status_pending = wstat;
|
|
|
|
/* Link the threads until the parent event is passed on to
|
|
higher layers. */
|
|
event_lwp->fork_relative = child_lwp;
|
|
child_lwp->fork_relative = event_lwp;
|
|
|
|
/* If the parent thread is doing step-over with single-step
|
|
breakpoints, the list of single-step breakpoints are cloned
|
|
from the parent's. Remove them from the child process.
|
|
In case of vfork, we'll reinsert them back once vforked
|
|
child is done. */
|
|
if (event_lwp->bp_reinsert != 0
|
|
&& can_software_single_step ())
|
|
{
|
|
/* The child process is forked and stopped, so it is safe
|
|
to access its memory without stopping all other threads
|
|
from other processes. */
|
|
delete_single_step_breakpoints (child_thr);
|
|
|
|
gdb_assert (has_single_step_breakpoints (event_thr));
|
|
gdb_assert (!has_single_step_breakpoints (child_thr));
|
|
}
|
|
|
|
/* Report the event. */
|
|
return 0;
|
|
}
|
|
|
|
if (debug_threads)
|
|
debug_printf ("HEW: Got clone event "
|
|
"from LWP %ld, new child is LWP %ld\n",
|
|
lwpid_of (event_thr), new_pid);
|
|
|
|
ptid = ptid_build (pid_of (event_thr), new_pid, 0);
|
|
new_lwp = add_lwp (ptid);
|
|
|
|
/* Either we're going to immediately resume the new thread
|
|
or leave it stopped. linux_resume_one_lwp is a nop if it
|
|
thinks the thread is currently running, so set this first
|
|
before calling linux_resume_one_lwp. */
|
|
new_lwp->stopped = 1;
|
|
|
|
/* If we're suspending all threads, leave this one suspended
|
|
too. If the fork/clone parent is stepping over a breakpoint,
|
|
all other threads have been suspended already. Leave the
|
|
child suspended too. */
|
|
if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS
|
|
|| event_lwp->bp_reinsert != 0)
|
|
new_lwp->suspended = 1;
|
|
|
|
/* Normally we will get the pending SIGSTOP. But in some cases
|
|
we might get another signal delivered to the group first.
|
|
If we do get another signal, be sure not to lose it. */
|
|
if (WSTOPSIG (status) != SIGSTOP)
|
|
{
|
|
new_lwp->stop_expected = 1;
|
|
new_lwp->status_pending_p = 1;
|
|
new_lwp->status_pending = status;
|
|
}
|
|
else if (report_thread_events)
|
|
{
|
|
new_lwp->waitstatus.kind = TARGET_WAITKIND_THREAD_CREATED;
|
|
new_lwp->status_pending_p = 1;
|
|
new_lwp->status_pending = status;
|
|
}
|
|
|
|
thread_db_notice_clone (event_thr, ptid);
|
|
|
|
/* Don't report the event. */
|
|
return 1;
|
|
}
|
|
else if (event == PTRACE_EVENT_VFORK_DONE)
|
|
{
|
|
event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE;
|
|
|
|
if (event_lwp->bp_reinsert != 0 && can_software_single_step ())
|
|
{
|
|
reinsert_single_step_breakpoints (event_thr);
|
|
|
|
gdb_assert (has_single_step_breakpoints (event_thr));
|
|
}
|
|
|
|
/* Report the event. */
|
|
return 0;
|
|
}
|
|
else if (event == PTRACE_EVENT_EXEC && report_exec_events)
|
|
{
|
|
struct process_info *proc;
|
|
std::vector<int> syscalls_to_catch;
|
|
ptid_t event_ptid;
|
|
pid_t event_pid;
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("HEW: Got exec event from LWP %ld\n",
|
|
lwpid_of (event_thr));
|
|
}
|
|
|
|
/* Get the event ptid. */
|
|
event_ptid = ptid_of (event_thr);
|
|
event_pid = ptid_get_pid (event_ptid);
|
|
|
|
/* Save the syscall list from the execing process. */
|
|
proc = get_thread_process (event_thr);
|
|
syscalls_to_catch = std::move (proc->syscalls_to_catch);
|
|
|
|
/* Delete the execing process and all its threads. */
|
|
linux_mourn (proc);
|
|
current_thread = NULL;
|
|
|
|
/* Create a new process/lwp/thread. */
|
|
proc = linux_add_process (event_pid, 0);
|
|
event_lwp = add_lwp (event_ptid);
|
|
event_thr = get_lwp_thread (event_lwp);
|
|
gdb_assert (current_thread == event_thr);
|
|
linux_arch_setup_thread (event_thr);
|
|
|
|
/* Set the event status. */
|
|
event_lwp->waitstatus.kind = TARGET_WAITKIND_EXECD;
|
|
event_lwp->waitstatus.value.execd_pathname
|
|
= xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr)));
|
|
|
|
/* Mark the exec status as pending. */
|
|
event_lwp->stopped = 1;
|
|
event_lwp->status_pending_p = 1;
|
|
event_lwp->status_pending = wstat;
|
|
event_thr->last_resume_kind = resume_continue;
|
|
event_thr->last_status.kind = TARGET_WAITKIND_IGNORE;
|
|
|
|
/* Update syscall state in the new lwp, effectively mid-syscall too. */
|
|
event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
|
|
|
|
/* Restore the list to catch. Don't rely on the client, which is free
|
|
to avoid sending a new list when the architecture doesn't change.
|
|
Also, for ANY_SYSCALL, the architecture doesn't really matter. */
|
|
proc->syscalls_to_catch = std::move (syscalls_to_catch);
|
|
|
|
/* Report the event. */
|
|
*orig_event_lwp = event_lwp;
|
|
return 0;
|
|
}
|
|
|
|
internal_error (__FILE__, __LINE__, _("unknown ptrace event %d"), event);
|
|
}
|
|
|
|
/* Return the PC as read from the regcache of LWP, without any
|
|
adjustment. */
|
|
|
|
static CORE_ADDR
|
|
get_pc (struct lwp_info *lwp)
|
|
{
|
|
struct thread_info *saved_thread;
|
|
struct regcache *regcache;
|
|
CORE_ADDR pc;
|
|
|
|
if (the_low_target.get_pc == NULL)
|
|
return 0;
|
|
|
|
saved_thread = current_thread;
|
|
current_thread = get_lwp_thread (lwp);
|
|
|
|
regcache = get_thread_regcache (current_thread, 1);
|
|
pc = (*the_low_target.get_pc) (regcache);
|
|
|
|
if (debug_threads)
|
|
debug_printf ("pc is 0x%lx\n", (long) pc);
|
|
|
|
current_thread = saved_thread;
|
|
return pc;
|
|
}
|
|
|
|
/* This function should only be called if LWP got a SYSCALL_SIGTRAP.
|
|
Fill *SYSNO with the syscall nr trapped. */
|
|
|
|
static void
|
|
get_syscall_trapinfo (struct lwp_info *lwp, int *sysno)
|
|
{
|
|
struct thread_info *saved_thread;
|
|
struct regcache *regcache;
|
|
|
|
if (the_low_target.get_syscall_trapinfo == NULL)
|
|
{
|
|
/* If we cannot get the syscall trapinfo, report an unknown
|
|
system call number. */
|
|
*sysno = UNKNOWN_SYSCALL;
|
|
return;
|
|
}
|
|
|
|
saved_thread = current_thread;
|
|
current_thread = get_lwp_thread (lwp);
|
|
|
|
regcache = get_thread_regcache (current_thread, 1);
|
|
(*the_low_target.get_syscall_trapinfo) (regcache, sysno);
|
|
|
|
if (debug_threads)
|
|
debug_printf ("get_syscall_trapinfo sysno %d\n", *sysno);
|
|
|
|
current_thread = saved_thread;
|
|
}
|
|
|
|
static int check_stopped_by_watchpoint (struct lwp_info *child);
|
|
|
|
/* Called when the LWP stopped for a signal/trap. If it stopped for a
|
|
trap check what caused it (breakpoint, watchpoint, trace, etc.),
|
|
and save the result in the LWP's stop_reason field. If it stopped
|
|
for a breakpoint, decrement the PC if necessary on the lwp's
|
|
architecture. Returns true if we now have the LWP's stop PC. */
|
|
|
|
static int
|
|
save_stop_reason (struct lwp_info *lwp)
|
|
{
|
|
CORE_ADDR pc;
|
|
CORE_ADDR sw_breakpoint_pc;
|
|
struct thread_info *saved_thread;
|
|
#if USE_SIGTRAP_SIGINFO
|
|
siginfo_t siginfo;
|
|
#endif
|
|
|
|
if (the_low_target.get_pc == NULL)
|
|
return 0;
|
|
|
|
pc = get_pc (lwp);
|
|
sw_breakpoint_pc = pc - the_low_target.decr_pc_after_break;
|
|
|
|
/* breakpoint_at reads from the current thread. */
|
|
saved_thread = current_thread;
|
|
current_thread = get_lwp_thread (lwp);
|
|
|
|
#if USE_SIGTRAP_SIGINFO
|
|
if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
|
|
(PTRACE_TYPE_ARG3) 0, &siginfo) == 0)
|
|
{
|
|
if (siginfo.si_signo == SIGTRAP)
|
|
{
|
|
if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code)
|
|
&& GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
|
|
{
|
|
/* The si_code is ambiguous on this arch -- check debug
|
|
registers. */
|
|
if (!check_stopped_by_watchpoint (lwp))
|
|
lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
|
|
}
|
|
else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code))
|
|
{
|
|
/* If we determine the LWP stopped for a SW breakpoint,
|
|
trust it. Particularly don't check watchpoint
|
|
registers, because at least on s390, we'd find
|
|
stopped-by-watchpoint as long as there's a watchpoint
|
|
set. */
|
|
lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
|
|
}
|
|
else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
|
|
{
|
|
/* This can indicate either a hardware breakpoint or
|
|
hardware watchpoint. Check debug registers. */
|
|
if (!check_stopped_by_watchpoint (lwp))
|
|
lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
|
|
}
|
|
else if (siginfo.si_code == TRAP_TRACE)
|
|
{
|
|
/* We may have single stepped an instruction that
|
|
triggered a watchpoint. In that case, on some
|
|
architectures (such as x86), instead of TRAP_HWBKPT,
|
|
si_code indicates TRAP_TRACE, and we need to check
|
|
the debug registers separately. */
|
|
if (!check_stopped_by_watchpoint (lwp))
|
|
lwp->stop_reason = TARGET_STOPPED_BY_SINGLE_STEP;
|
|
}
|
|
}
|
|
}
|
|
#else
|
|
/* We may have just stepped a breakpoint instruction. E.g., in
|
|
non-stop mode, GDB first tells the thread A to step a range, and
|
|
then the user inserts a breakpoint inside the range. In that
|
|
case we need to report the breakpoint PC. */
|
|
if ((!lwp->stepping || lwp->stop_pc == sw_breakpoint_pc)
|
|
&& (*the_low_target.breakpoint_at) (sw_breakpoint_pc))
|
|
lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
|
|
|
|
if (hardware_breakpoint_inserted_here (pc))
|
|
lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
|
|
|
|
if (lwp->stop_reason == TARGET_STOPPED_BY_NO_REASON)
|
|
check_stopped_by_watchpoint (lwp);
|
|
#endif
|
|
|
|
if (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT)
|
|
{
|
|
if (debug_threads)
|
|
{
|
|
struct thread_info *thr = get_lwp_thread (lwp);
|
|
|
|
debug_printf ("CSBB: %s stopped by software breakpoint\n",
|
|
target_pid_to_str (ptid_of (thr)));
|
|
}
|
|
|
|
/* Back up the PC if necessary. */
|
|
if (pc != sw_breakpoint_pc)
|
|
{
|
|
struct regcache *regcache
|
|
= get_thread_regcache (current_thread, 1);
|
|
(*the_low_target.set_pc) (regcache, sw_breakpoint_pc);
|
|
}
|
|
|
|
/* Update this so we record the correct stop PC below. */
|
|
pc = sw_breakpoint_pc;
|
|
}
|
|
else if (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT)
|
|
{
|
|
if (debug_threads)
|
|
{
|
|
struct thread_info *thr = get_lwp_thread (lwp);
|
|
|
|
debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
|
|
target_pid_to_str (ptid_of (thr)));
|
|
}
|
|
}
|
|
else if (lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT)
|
|
{
|
|
if (debug_threads)
|
|
{
|
|
struct thread_info *thr = get_lwp_thread (lwp);
|
|
|
|
debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
|
|
target_pid_to_str (ptid_of (thr)));
|
|
}
|
|
}
|
|
else if (lwp->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP)
|
|
{
|
|
if (debug_threads)
|
|
{
|
|
struct thread_info *thr = get_lwp_thread (lwp);
|
|
|
|
debug_printf ("CSBB: %s stopped by trace\n",
|
|
target_pid_to_str (ptid_of (thr)));
|
|
}
|
|
}
|
|
|
|
lwp->stop_pc = pc;
|
|
current_thread = saved_thread;
|
|
return 1;
|
|
}
|
|
|
|
static struct lwp_info *
|
|
add_lwp (ptid_t ptid)
|
|
{
|
|
struct lwp_info *lwp;
|
|
|
|
lwp = XCNEW (struct lwp_info);
|
|
|
|
lwp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
|
|
|
|
if (the_low_target.new_thread != NULL)
|
|
the_low_target.new_thread (lwp);
|
|
|
|
lwp->thread = add_thread (ptid, lwp);
|
|
|
|
return lwp;
|
|
}
|
|
|
|
/* Callback to be used when calling fork_inferior, responsible for
|
|
actually initiating the tracing of the inferior. */
|
|
|
|
static void
|
|
linux_ptrace_fun ()
|
|
{
|
|
if (ptrace (PTRACE_TRACEME, 0, (PTRACE_TYPE_ARG3) 0,
|
|
(PTRACE_TYPE_ARG4) 0) < 0)
|
|
trace_start_error_with_name ("ptrace");
|
|
|
|
if (setpgid (0, 0) < 0)
|
|
trace_start_error_with_name ("setpgid");
|
|
|
|
/* If GDBserver is connected to gdb via stdio, redirect the inferior's
|
|
stdout to stderr so that inferior i/o doesn't corrupt the connection.
|
|
Also, redirect stdin to /dev/null. */
|
|
if (remote_connection_is_stdio ())
|
|
{
|
|
if (close (0) < 0)
|
|
trace_start_error_with_name ("close");
|
|
if (open ("/dev/null", O_RDONLY) < 0)
|
|
trace_start_error_with_name ("open");
|
|
if (dup2 (2, 1) < 0)
|
|
trace_start_error_with_name ("dup2");
|
|
if (write (2, "stdin/stdout redirected\n",
|
|
sizeof ("stdin/stdout redirected\n") - 1) < 0)
|
|
{
|
|
/* Errors ignored. */;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Start an inferior process and returns its pid.
|
|
PROGRAM is the name of the program to be started, and PROGRAM_ARGS
|
|
are its arguments. */
|
|
|
|
static int
|
|
linux_create_inferior (const char *program,
|
|
const std::vector<char *> &program_args)
|
|
{
|
|
struct lwp_info *new_lwp;
|
|
int pid;
|
|
ptid_t ptid;
|
|
|
|
{
|
|
maybe_disable_address_space_randomization restore_personality
|
|
(disable_randomization);
|
|
std::string str_program_args = stringify_argv (program_args);
|
|
|
|
pid = fork_inferior (program,
|
|
str_program_args.c_str (),
|
|
get_environ ()->envp (), linux_ptrace_fun,
|
|
NULL, NULL, NULL, NULL);
|
|
}
|
|
|
|
linux_add_process (pid, 0);
|
|
|
|
ptid = ptid_build (pid, pid, 0);
|
|
new_lwp = add_lwp (ptid);
|
|
new_lwp->must_set_ptrace_flags = 1;
|
|
|
|
post_fork_inferior (pid, program);
|
|
|
|
return pid;
|
|
}
|
|
|
|
/* Implement the post_create_inferior target_ops method. */
|
|
|
|
static void
|
|
linux_post_create_inferior (void)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (current_thread);
|
|
|
|
linux_arch_setup ();
|
|
|
|
if (lwp->must_set_ptrace_flags)
|
|
{
|
|
struct process_info *proc = current_process ();
|
|
int options = linux_low_ptrace_options (proc->attached);
|
|
|
|
linux_enable_event_reporting (lwpid_of (current_thread), options);
|
|
lwp->must_set_ptrace_flags = 0;
|
|
}
|
|
}
|
|
|
|
/* Attach to an inferior process. Returns 0 on success, ERRNO on
|
|
error. */
|
|
|
|
int
|
|
linux_attach_lwp (ptid_t ptid)
|
|
{
|
|
struct lwp_info *new_lwp;
|
|
int lwpid = ptid_get_lwp (ptid);
|
|
|
|
if (ptrace (PTRACE_ATTACH, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0)
|
|
!= 0)
|
|
return errno;
|
|
|
|
new_lwp = add_lwp (ptid);
|
|
|
|
/* We need to wait for SIGSTOP before being able to make the next
|
|
ptrace call on this LWP. */
|
|
new_lwp->must_set_ptrace_flags = 1;
|
|
|
|
if (linux_proc_pid_is_stopped (lwpid))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Attached to a stopped process\n");
|
|
|
|
/* The process is definitely stopped. It is in a job control
|
|
stop, unless the kernel predates the TASK_STOPPED /
|
|
TASK_TRACED distinction, in which case it might be in a
|
|
ptrace stop. Make sure it is in a ptrace stop; from there we
|
|
can kill it, signal it, et cetera.
|
|
|
|
First make sure there is a pending SIGSTOP. Since we are
|
|
already attached, the process can not transition from stopped
|
|
to running without a PTRACE_CONT; so we know this signal will
|
|
go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
|
|
probably already in the queue (unless this kernel is old
|
|
enough to use TASK_STOPPED for ptrace stops); but since
|
|
SIGSTOP is not an RT signal, it can only be queued once. */
|
|
kill_lwp (lwpid, SIGSTOP);
|
|
|
|
/* Finally, resume the stopped process. This will deliver the
|
|
SIGSTOP (or a higher priority signal, just like normal
|
|
PTRACE_ATTACH), which we'll catch later on. */
|
|
ptrace (PTRACE_CONT, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
|
|
}
|
|
|
|
/* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
|
|
brings it to a halt.
|
|
|
|
There are several cases to consider here:
|
|
|
|
1) gdbserver has already attached to the process and is being notified
|
|
of a new thread that is being created.
|
|
In this case we should ignore that SIGSTOP and resume the
|
|
process. This is handled below by setting stop_expected = 1,
|
|
and the fact that add_thread sets last_resume_kind ==
|
|
resume_continue.
|
|
|
|
2) This is the first thread (the process thread), and we're attaching
|
|
to it via attach_inferior.
|
|
In this case we want the process thread to stop.
|
|
This is handled by having linux_attach set last_resume_kind ==
|
|
resume_stop after we return.
|
|
|
|
If the pid we are attaching to is also the tgid, we attach to and
|
|
stop all the existing threads. Otherwise, we attach to pid and
|
|
ignore any other threads in the same group as this pid.
|
|
|
|
3) GDB is connecting to gdbserver and is requesting an enumeration of all
|
|
existing threads.
|
|
In this case we want the thread to stop.
|
|
FIXME: This case is currently not properly handled.
|
|
We should wait for the SIGSTOP but don't. Things work apparently
|
|
because enough time passes between when we ptrace (ATTACH) and when
|
|
gdb makes the next ptrace call on the thread.
|
|
|
|
On the other hand, if we are currently trying to stop all threads, we
|
|
should treat the new thread as if we had sent it a SIGSTOP. This works
|
|
because we are guaranteed that the add_lwp call above added us to the
|
|
end of the list, and so the new thread has not yet reached
|
|
wait_for_sigstop (but will). */
|
|
new_lwp->stop_expected = 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
|
|
already attached. Returns true if a new LWP is found, false
|
|
otherwise. */
|
|
|
|
static int
|
|
attach_proc_task_lwp_callback (ptid_t ptid)
|
|
{
|
|
/* Is this a new thread? */
|
|
if (find_thread_ptid (ptid) == NULL)
|
|
{
|
|
int lwpid = ptid_get_lwp (ptid);
|
|
int err;
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Found new lwp %d\n", lwpid);
|
|
|
|
err = linux_attach_lwp (ptid);
|
|
|
|
/* Be quiet if we simply raced with the thread exiting. EPERM
|
|
is returned if the thread's task still exists, and is marked
|
|
as exited or zombie, as well as other conditions, so in that
|
|
case, confirm the status in /proc/PID/status. */
|
|
if (err == ESRCH
|
|
|| (err == EPERM && linux_proc_pid_is_gone (lwpid)))
|
|
{
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("Cannot attach to lwp %d: "
|
|
"thread is gone (%d: %s)\n",
|
|
lwpid, err, strerror (err));
|
|
}
|
|
}
|
|
else if (err != 0)
|
|
{
|
|
warning (_("Cannot attach to lwp %d: %s"),
|
|
lwpid,
|
|
linux_ptrace_attach_fail_reason_string (ptid, err));
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void async_file_mark (void);
|
|
|
|
/* Attach to PID. If PID is the tgid, attach to it and all
|
|
of its threads. */
|
|
|
|
static int
|
|
linux_attach (unsigned long pid)
|
|
{
|
|
struct process_info *proc;
|
|
struct thread_info *initial_thread;
|
|
ptid_t ptid = ptid_build (pid, pid, 0);
|
|
int err;
|
|
|
|
/* Attach to PID. We will check for other threads
|
|
soon. */
|
|
err = linux_attach_lwp (ptid);
|
|
if (err != 0)
|
|
error ("Cannot attach to process %ld: %s",
|
|
pid, linux_ptrace_attach_fail_reason_string (ptid, err));
|
|
|
|
proc = linux_add_process (pid, 1);
|
|
|
|
/* Don't ignore the initial SIGSTOP if we just attached to this
|
|
process. It will be collected by wait shortly. */
|
|
initial_thread = find_thread_ptid (ptid_build (pid, pid, 0));
|
|
initial_thread->last_resume_kind = resume_stop;
|
|
|
|
/* We must attach to every LWP. If /proc is mounted, use that to
|
|
find them now. On the one hand, the inferior may be using raw
|
|
clone instead of using pthreads. On the other hand, even if it
|
|
is using pthreads, GDB may not be connected yet (thread_db needs
|
|
to do symbol lookups, through qSymbol). Also, thread_db walks
|
|
structures in the inferior's address space to find the list of
|
|
threads/LWPs, and those structures may well be corrupted. Note
|
|
that once thread_db is loaded, we'll still use it to list threads
|
|
and associate pthread info with each LWP. */
|
|
linux_proc_attach_tgid_threads (pid, attach_proc_task_lwp_callback);
|
|
|
|
/* GDB will shortly read the xml target description for this
|
|
process, to figure out the process' architecture. But the target
|
|
description is only filled in when the first process/thread in
|
|
the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
|
|
that now, otherwise, if GDB is fast enough, it could read the
|
|
target description _before_ that initial stop. */
|
|
if (non_stop)
|
|
{
|
|
struct lwp_info *lwp;
|
|
int wstat, lwpid;
|
|
ptid_t pid_ptid = pid_to_ptid (pid);
|
|
|
|
lwpid = linux_wait_for_event_filtered (pid_ptid, pid_ptid,
|
|
&wstat, __WALL);
|
|
gdb_assert (lwpid > 0);
|
|
|
|
lwp = find_lwp_pid (pid_to_ptid (lwpid));
|
|
|
|
if (!WIFSTOPPED (wstat) || WSTOPSIG (wstat) != SIGSTOP)
|
|
{
|
|
lwp->status_pending_p = 1;
|
|
lwp->status_pending = wstat;
|
|
}
|
|
|
|
initial_thread->last_resume_kind = resume_continue;
|
|
|
|
async_file_mark ();
|
|
|
|
gdb_assert (proc->tdesc != NULL);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
last_thread_of_process_p (int pid)
|
|
{
|
|
bool seen_one = false;
|
|
|
|
thread_info *thread = find_thread (pid, [&] (thread_info *thread)
|
|
{
|
|
if (!seen_one)
|
|
{
|
|
/* This is the first thread of this process we see. */
|
|
seen_one = true;
|
|
return false;
|
|
}
|
|
else
|
|
{
|
|
/* This is the second thread of this process we see. */
|
|
return true;
|
|
}
|
|
});
|
|
|
|
return thread == NULL;
|
|
}
|
|
|
|
/* Kill LWP. */
|
|
|
|
static void
|
|
linux_kill_one_lwp (struct lwp_info *lwp)
|
|
{
|
|
struct thread_info *thr = get_lwp_thread (lwp);
|
|
int pid = lwpid_of (thr);
|
|
|
|
/* PTRACE_KILL is unreliable. After stepping into a signal handler,
|
|
there is no signal context, and ptrace(PTRACE_KILL) (or
|
|
ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
|
|
ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
|
|
alternative is to kill with SIGKILL. We only need one SIGKILL
|
|
per process, not one for each thread. But since we still support
|
|
support debugging programs using raw clone without CLONE_THREAD,
|
|
we send one for each thread. For years, we used PTRACE_KILL
|
|
only, so we're being a bit paranoid about some old kernels where
|
|
PTRACE_KILL might work better (dubious if there are any such, but
|
|
that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
|
|
second, and so we're fine everywhere. */
|
|
|
|
errno = 0;
|
|
kill_lwp (pid, SIGKILL);
|
|
if (debug_threads)
|
|
{
|
|
int save_errno = errno;
|
|
|
|
debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
|
|
target_pid_to_str (ptid_of (thr)),
|
|
save_errno ? strerror (save_errno) : "OK");
|
|
}
|
|
|
|
errno = 0;
|
|
ptrace (PTRACE_KILL, pid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
|
|
if (debug_threads)
|
|
{
|
|
int save_errno = errno;
|
|
|
|
debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
|
|
target_pid_to_str (ptid_of (thr)),
|
|
save_errno ? strerror (save_errno) : "OK");
|
|
}
|
|
}
|
|
|
|
/* Kill LWP and wait for it to die. */
|
|
|
|
static void
|
|
kill_wait_lwp (struct lwp_info *lwp)
|
|
{
|
|
struct thread_info *thr = get_lwp_thread (lwp);
|
|
int pid = ptid_get_pid (ptid_of (thr));
|
|
int lwpid = ptid_get_lwp (ptid_of (thr));
|
|
int wstat;
|
|
int res;
|
|
|
|
if (debug_threads)
|
|
debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid, pid);
|
|
|
|
do
|
|
{
|
|
linux_kill_one_lwp (lwp);
|
|
|
|
/* Make sure it died. Notes:
|
|
|
|
- The loop is most likely unnecessary.
|
|
|
|
- We don't use linux_wait_for_event as that could delete lwps
|
|
while we're iterating over them. We're not interested in
|
|
any pending status at this point, only in making sure all
|
|
wait status on the kernel side are collected until the
|
|
process is reaped.
|
|
|
|
- We don't use __WALL here as the __WALL emulation relies on
|
|
SIGCHLD, and killing a stopped process doesn't generate
|
|
one, nor an exit status.
|
|
*/
|
|
res = my_waitpid (lwpid, &wstat, 0);
|
|
if (res == -1 && errno == ECHILD)
|
|
res = my_waitpid (lwpid, &wstat, __WCLONE);
|
|
} while (res > 0 && WIFSTOPPED (wstat));
|
|
|
|
/* Even if it was stopped, the child may have already disappeared.
|
|
E.g., if it was killed by SIGKILL. */
|
|
if (res < 0 && errno != ECHILD)
|
|
perror_with_name ("kill_wait_lwp");
|
|
}
|
|
|
|
/* Callback for `for_each_thread'. Kills an lwp of a given process,
|
|
except the leader. */
|
|
|
|
static void
|
|
kill_one_lwp_callback (thread_info *thread, int pid)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (thread);
|
|
|
|
/* We avoid killing the first thread here, because of a Linux kernel (at
|
|
least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
|
|
the children get a chance to be reaped, it will remain a zombie
|
|
forever. */
|
|
|
|
if (lwpid_of (thread) == pid)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("lkop: is last of process %s\n",
|
|
target_pid_to_str (thread->id));
|
|
return;
|
|
}
|
|
|
|
kill_wait_lwp (lwp);
|
|
}
|
|
|
|
static int
|
|
linux_kill (int pid)
|
|
{
|
|
struct process_info *process;
|
|
struct lwp_info *lwp;
|
|
|
|
process = find_process_pid (pid);
|
|
if (process == NULL)
|
|
return -1;
|
|
|
|
/* If we're killing a running inferior, make sure it is stopped
|
|
first, as PTRACE_KILL will not work otherwise. */
|
|
stop_all_lwps (0, NULL);
|
|
|
|
for_each_thread (pid, [&] (thread_info *thread)
|
|
{
|
|
kill_one_lwp_callback (thread, pid);
|
|
});
|
|
|
|
/* See the comment in linux_kill_one_lwp. We did not kill the first
|
|
thread in the list, so do so now. */
|
|
lwp = find_lwp_pid (pid_to_ptid (pid));
|
|
|
|
if (lwp == NULL)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("lk_1: cannot find lwp for pid: %d\n",
|
|
pid);
|
|
}
|
|
else
|
|
kill_wait_lwp (lwp);
|
|
|
|
the_target->mourn (process);
|
|
|
|
/* Since we presently can only stop all lwps of all processes, we
|
|
need to unstop lwps of other processes. */
|
|
unstop_all_lwps (0, NULL);
|
|
return 0;
|
|
}
|
|
|
|
/* Get pending signal of THREAD, for detaching purposes. This is the
|
|
signal the thread last stopped for, which we need to deliver to the
|
|
thread when detaching, otherwise, it'd be suppressed/lost. */
|
|
|
|
static int
|
|
get_detach_signal (struct thread_info *thread)
|
|
{
|
|
enum gdb_signal signo = GDB_SIGNAL_0;
|
|
int status;
|
|
struct lwp_info *lp = get_thread_lwp (thread);
|
|
|
|
if (lp->status_pending_p)
|
|
status = lp->status_pending;
|
|
else
|
|
{
|
|
/* If the thread had been suspended by gdbserver, and it stopped
|
|
cleanly, then it'll have stopped with SIGSTOP. But we don't
|
|
want to deliver that SIGSTOP. */
|
|
if (thread->last_status.kind != TARGET_WAITKIND_STOPPED
|
|
|| thread->last_status.value.sig == GDB_SIGNAL_0)
|
|
return 0;
|
|
|
|
/* Otherwise, we may need to deliver the signal we
|
|
intercepted. */
|
|
status = lp->last_status;
|
|
}
|
|
|
|
if (!WIFSTOPPED (status))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
|
|
target_pid_to_str (ptid_of (thread)));
|
|
return 0;
|
|
}
|
|
|
|
/* Extended wait statuses aren't real SIGTRAPs. */
|
|
if (WSTOPSIG (status) == SIGTRAP && linux_is_extended_waitstatus (status))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("GPS: lwp %s had stopped with extended "
|
|
"status: no pending signal\n",
|
|
target_pid_to_str (ptid_of (thread)));
|
|
return 0;
|
|
}
|
|
|
|
signo = gdb_signal_from_host (WSTOPSIG (status));
|
|
|
|
if (program_signals_p && !program_signals[signo])
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
|
|
target_pid_to_str (ptid_of (thread)),
|
|
gdb_signal_to_string (signo));
|
|
return 0;
|
|
}
|
|
else if (!program_signals_p
|
|
/* If we have no way to know which signals GDB does not
|
|
want to have passed to the program, assume
|
|
SIGTRAP/SIGINT, which is GDB's default. */
|
|
&& (signo == GDB_SIGNAL_TRAP || signo == GDB_SIGNAL_INT))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("GPS: lwp %s had signal %s, "
|
|
"but we don't know if we should pass it. "
|
|
"Default to not.\n",
|
|
target_pid_to_str (ptid_of (thread)),
|
|
gdb_signal_to_string (signo));
|
|
return 0;
|
|
}
|
|
else
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
|
|
target_pid_to_str (ptid_of (thread)),
|
|
gdb_signal_to_string (signo));
|
|
|
|
return WSTOPSIG (status);
|
|
}
|
|
}
|
|
|
|
/* Detach from LWP. */
|
|
|
|
static void
|
|
linux_detach_one_lwp (struct lwp_info *lwp)
|
|
{
|
|
struct thread_info *thread = get_lwp_thread (lwp);
|
|
int sig;
|
|
int lwpid;
|
|
|
|
/* If there is a pending SIGSTOP, get rid of it. */
|
|
if (lwp->stop_expected)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Sending SIGCONT to %s\n",
|
|
target_pid_to_str (ptid_of (thread)));
|
|
|
|
kill_lwp (lwpid_of (thread), SIGCONT);
|
|
lwp->stop_expected = 0;
|
|
}
|
|
|
|
/* Pass on any pending signal for this thread. */
|
|
sig = get_detach_signal (thread);
|
|
|
|
/* Preparing to resume may try to write registers, and fail if the
|
|
lwp is zombie. If that happens, ignore the error. We'll handle
|
|
it below, when detach fails with ESRCH. */
|
|
TRY
|
|
{
|
|
/* Flush any pending changes to the process's registers. */
|
|
regcache_invalidate_thread (thread);
|
|
|
|
/* Finally, let it resume. */
|
|
if (the_low_target.prepare_to_resume != NULL)
|
|
the_low_target.prepare_to_resume (lwp);
|
|
}
|
|
CATCH (ex, RETURN_MASK_ERROR)
|
|
{
|
|
if (!check_ptrace_stopped_lwp_gone (lwp))
|
|
throw_exception (ex);
|
|
}
|
|
END_CATCH
|
|
|
|
lwpid = lwpid_of (thread);
|
|
if (ptrace (PTRACE_DETACH, lwpid, (PTRACE_TYPE_ARG3) 0,
|
|
(PTRACE_TYPE_ARG4) (long) sig) < 0)
|
|
{
|
|
int save_errno = errno;
|
|
|
|
/* We know the thread exists, so ESRCH must mean the lwp is
|
|
zombie. This can happen if one of the already-detached
|
|
threads exits the whole thread group. In that case we're
|
|
still attached, and must reap the lwp. */
|
|
if (save_errno == ESRCH)
|
|
{
|
|
int ret, status;
|
|
|
|
ret = my_waitpid (lwpid, &status, __WALL);
|
|
if (ret == -1)
|
|
{
|
|
warning (_("Couldn't reap LWP %d while detaching: %s"),
|
|
lwpid, strerror (errno));
|
|
}
|
|
else if (!WIFEXITED (status) && !WIFSIGNALED (status))
|
|
{
|
|
warning (_("Reaping LWP %d while detaching "
|
|
"returned unexpected status 0x%x"),
|
|
lwpid, status);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
error (_("Can't detach %s: %s"),
|
|
target_pid_to_str (ptid_of (thread)),
|
|
strerror (save_errno));
|
|
}
|
|
}
|
|
else if (debug_threads)
|
|
{
|
|
debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)\n",
|
|
target_pid_to_str (ptid_of (thread)),
|
|
strsignal (sig));
|
|
}
|
|
|
|
delete_lwp (lwp);
|
|
}
|
|
|
|
/* Callback for for_each_thread. Detaches from non-leader threads of a
|
|
given process. */
|
|
|
|
static void
|
|
linux_detach_lwp_callback (thread_info *thread)
|
|
{
|
|
/* We don't actually detach from the thread group leader just yet.
|
|
If the thread group exits, we must reap the zombie clone lwps
|
|
before we're able to reap the leader. */
|
|
if (thread->id.pid () == thread->id.lwp ())
|
|
return;
|
|
|
|
lwp_info *lwp = get_thread_lwp (thread);
|
|
linux_detach_one_lwp (lwp);
|
|
}
|
|
|
|
static int
|
|
linux_detach (int pid)
|
|
{
|
|
struct process_info *process;
|
|
struct lwp_info *main_lwp;
|
|
|
|
process = find_process_pid (pid);
|
|
if (process == NULL)
|
|
return -1;
|
|
|
|
/* As there's a step over already in progress, let it finish first,
|
|
otherwise nesting a stabilize_threads operation on top gets real
|
|
messy. */
|
|
complete_ongoing_step_over ();
|
|
|
|
/* Stop all threads before detaching. First, ptrace requires that
|
|
the thread is stopped to sucessfully detach. Second, thread_db
|
|
may need to uninstall thread event breakpoints from memory, which
|
|
only works with a stopped process anyway. */
|
|
stop_all_lwps (0, NULL);
|
|
|
|
#ifdef USE_THREAD_DB
|
|
thread_db_detach (process);
|
|
#endif
|
|
|
|
/* Stabilize threads (move out of jump pads). */
|
|
stabilize_threads ();
|
|
|
|
/* Detach from the clone lwps first. If the thread group exits just
|
|
while we're detaching, we must reap the clone lwps before we're
|
|
able to reap the leader. */
|
|
for_each_thread (pid, linux_detach_lwp_callback);
|
|
|
|
main_lwp = find_lwp_pid (pid_to_ptid (pid));
|
|
linux_detach_one_lwp (main_lwp);
|
|
|
|
the_target->mourn (process);
|
|
|
|
/* Since we presently can only stop all lwps of all processes, we
|
|
need to unstop lwps of other processes. */
|
|
unstop_all_lwps (0, NULL);
|
|
return 0;
|
|
}
|
|
|
|
/* Remove all LWPs that belong to process PROC from the lwp list. */
|
|
|
|
static void
|
|
linux_mourn (struct process_info *process)
|
|
{
|
|
struct process_info_private *priv;
|
|
|
|
#ifdef USE_THREAD_DB
|
|
thread_db_mourn (process);
|
|
#endif
|
|
|
|
for_each_thread (process->pid, [] (thread_info *thread)
|
|
{
|
|
delete_lwp (get_thread_lwp (thread));
|
|
});
|
|
|
|
/* Freeing all private data. */
|
|
priv = process->priv;
|
|
if (the_low_target.delete_process != NULL)
|
|
the_low_target.delete_process (priv->arch_private);
|
|
else
|
|
gdb_assert (priv->arch_private == NULL);
|
|
free (priv);
|
|
process->priv = NULL;
|
|
|
|
remove_process (process);
|
|
}
|
|
|
|
static void
|
|
linux_join (int pid)
|
|
{
|
|
int status, ret;
|
|
|
|
do {
|
|
ret = my_waitpid (pid, &status, 0);
|
|
if (WIFEXITED (status) || WIFSIGNALED (status))
|
|
break;
|
|
} while (ret != -1 || errno != ECHILD);
|
|
}
|
|
|
|
/* Return nonzero if the given thread is still alive. */
|
|
static int
|
|
linux_thread_alive (ptid_t ptid)
|
|
{
|
|
struct lwp_info *lwp = find_lwp_pid (ptid);
|
|
|
|
/* We assume we always know if a thread exits. If a whole process
|
|
exited but we still haven't been able to report it to GDB, we'll
|
|
hold on to the last lwp of the dead process. */
|
|
if (lwp != NULL)
|
|
return !lwp_is_marked_dead (lwp);
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
/* Return 1 if this lwp still has an interesting status pending. If
|
|
not (e.g., it had stopped for a breakpoint that is gone), return
|
|
false. */
|
|
|
|
static int
|
|
thread_still_has_status_pending_p (struct thread_info *thread)
|
|
{
|
|
struct lwp_info *lp = get_thread_lwp (thread);
|
|
|
|
if (!lp->status_pending_p)
|
|
return 0;
|
|
|
|
if (thread->last_resume_kind != resume_stop
|
|
&& (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
|
|
|| lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT))
|
|
{
|
|
struct thread_info *saved_thread;
|
|
CORE_ADDR pc;
|
|
int discard = 0;
|
|
|
|
gdb_assert (lp->last_status != 0);
|
|
|
|
pc = get_pc (lp);
|
|
|
|
saved_thread = current_thread;
|
|
current_thread = thread;
|
|
|
|
if (pc != lp->stop_pc)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("PC of %ld changed\n",
|
|
lwpid_of (thread));
|
|
discard = 1;
|
|
}
|
|
|
|
#if !USE_SIGTRAP_SIGINFO
|
|
else if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
|
|
&& !(*the_low_target.breakpoint_at) (pc))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("previous SW breakpoint of %ld gone\n",
|
|
lwpid_of (thread));
|
|
discard = 1;
|
|
}
|
|
else if (lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT
|
|
&& !hardware_breakpoint_inserted_here (pc))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("previous HW breakpoint of %ld gone\n",
|
|
lwpid_of (thread));
|
|
discard = 1;
|
|
}
|
|
#endif
|
|
|
|
current_thread = saved_thread;
|
|
|
|
if (discard)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("discarding pending breakpoint status\n");
|
|
lp->status_pending_p = 0;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/* Returns true if LWP is resumed from the client's perspective. */
|
|
|
|
static int
|
|
lwp_resumed (struct lwp_info *lwp)
|
|
{
|
|
struct thread_info *thread = get_lwp_thread (lwp);
|
|
|
|
if (thread->last_resume_kind != resume_stop)
|
|
return 1;
|
|
|
|
/* Did gdb send us a `vCont;t', but we haven't reported the
|
|
corresponding stop to gdb yet? If so, the thread is still
|
|
resumed/running from gdb's perspective. */
|
|
if (thread->last_resume_kind == resume_stop
|
|
&& thread->last_status.kind == TARGET_WAITKIND_IGNORE)
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Return true if this lwp has an interesting status pending. */
|
|
static bool
|
|
status_pending_p_callback (thread_info *thread, ptid_t ptid)
|
|
{
|
|
struct lwp_info *lp = get_thread_lwp (thread);
|
|
|
|
/* Check if we're only interested in events from a specific process
|
|
or a specific LWP. */
|
|
if (!thread->id.matches (ptid))
|
|
return 0;
|
|
|
|
if (!lwp_resumed (lp))
|
|
return 0;
|
|
|
|
if (lp->status_pending_p
|
|
&& !thread_still_has_status_pending_p (thread))
|
|
{
|
|
linux_resume_one_lwp (lp, lp->stepping, GDB_SIGNAL_0, NULL);
|
|
return 0;
|
|
}
|
|
|
|
return lp->status_pending_p;
|
|
}
|
|
|
|
struct lwp_info *
|
|
find_lwp_pid (ptid_t ptid)
|
|
{
|
|
thread_info *thread = find_thread ([&] (thread_info *thread)
|
|
{
|
|
int lwp = ptid.lwp () != 0 ? ptid.lwp () : ptid.pid ();
|
|
return thread->id.lwp () == lwp;
|
|
});
|
|
|
|
if (thread == NULL)
|
|
return NULL;
|
|
|
|
return get_thread_lwp (thread);
|
|
}
|
|
|
|
/* Return the number of known LWPs in the tgid given by PID. */
|
|
|
|
static int
|
|
num_lwps (int pid)
|
|
{
|
|
int count = 0;
|
|
|
|
for_each_thread (pid, [&] (thread_info *thread)
|
|
{
|
|
count++;
|
|
});
|
|
|
|
return count;
|
|
}
|
|
|
|
/* See nat/linux-nat.h. */
|
|
|
|
struct lwp_info *
|
|
iterate_over_lwps (ptid_t filter,
|
|
iterate_over_lwps_ftype callback,
|
|
void *data)
|
|
{
|
|
thread_info *thread = find_thread (filter, [&] (thread_info *thread)
|
|
{
|
|
lwp_info *lwp = get_thread_lwp (thread);
|
|
|
|
return callback (lwp, data);
|
|
});
|
|
|
|
if (thread == NULL)
|
|
return NULL;
|
|
|
|
return get_thread_lwp (thread);
|
|
}
|
|
|
|
/* Detect zombie thread group leaders, and "exit" them. We can't reap
|
|
their exits until all other threads in the group have exited. */
|
|
|
|
static void
|
|
check_zombie_leaders (void)
|
|
{
|
|
for_each_process ([] (process_info *proc) {
|
|
pid_t leader_pid = pid_of (proc);
|
|
struct lwp_info *leader_lp;
|
|
|
|
leader_lp = find_lwp_pid (pid_to_ptid (leader_pid));
|
|
|
|
if (debug_threads)
|
|
debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
|
|
"num_lwps=%d, zombie=%d\n",
|
|
leader_pid, leader_lp!= NULL, num_lwps (leader_pid),
|
|
linux_proc_pid_is_zombie (leader_pid));
|
|
|
|
if (leader_lp != NULL && !leader_lp->stopped
|
|
/* Check if there are other threads in the group, as we may
|
|
have raced with the inferior simply exiting. */
|
|
&& !last_thread_of_process_p (leader_pid)
|
|
&& linux_proc_pid_is_zombie (leader_pid))
|
|
{
|
|
/* A leader zombie can mean one of two things:
|
|
|
|
- It exited, and there's an exit status pending
|
|
available, or only the leader exited (not the whole
|
|
program). In the latter case, we can't waitpid the
|
|
leader's exit status until all other threads are gone.
|
|
|
|
- There are 3 or more threads in the group, and a thread
|
|
other than the leader exec'd. On an exec, the Linux
|
|
kernel destroys all other threads (except the execing
|
|
one) in the thread group, and resets the execing thread's
|
|
tid to the tgid. No exit notification is sent for the
|
|
execing thread -- from the ptracer's perspective, it
|
|
appears as though the execing thread just vanishes.
|
|
Until we reap all other threads except the leader and the
|
|
execing thread, the leader will be zombie, and the
|
|
execing thread will be in `D (disc sleep)'. As soon as
|
|
all other threads are reaped, the execing thread changes
|
|
it's tid to the tgid, and the previous (zombie) leader
|
|
vanishes, giving place to the "new" leader. We could try
|
|
distinguishing the exit and exec cases, by waiting once
|
|
more, and seeing if something comes out, but it doesn't
|
|
sound useful. The previous leader _does_ go away, and
|
|
we'll re-add the new one once we see the exec event
|
|
(which is just the same as what would happen if the
|
|
previous leader did exit voluntarily before some other
|
|
thread execs). */
|
|
|
|
if (debug_threads)
|
|
debug_printf ("CZL: Thread group leader %d zombie "
|
|
"(it exited, or another thread execd).\n",
|
|
leader_pid);
|
|
|
|
delete_lwp (leader_lp);
|
|
}
|
|
});
|
|
}
|
|
|
|
/* Callback for `find_thread'. Returns the first LWP that is not
|
|
stopped. */
|
|
|
|
static bool
|
|
not_stopped_callback (thread_info *thread, ptid_t filter)
|
|
{
|
|
if (!thread->id.matches (filter))
|
|
return false;
|
|
|
|
lwp_info *lwp = get_thread_lwp (thread);
|
|
|
|
return !lwp->stopped;
|
|
}
|
|
|
|
/* Increment LWP's suspend count. */
|
|
|
|
static void
|
|
lwp_suspended_inc (struct lwp_info *lwp)
|
|
{
|
|
lwp->suspended++;
|
|
|
|
if (debug_threads && lwp->suspended > 4)
|
|
{
|
|
struct thread_info *thread = get_lwp_thread (lwp);
|
|
|
|
debug_printf ("LWP %ld has a suspiciously high suspend count,"
|
|
" suspended=%d\n", lwpid_of (thread), lwp->suspended);
|
|
}
|
|
}
|
|
|
|
/* Decrement LWP's suspend count. */
|
|
|
|
static void
|
|
lwp_suspended_decr (struct lwp_info *lwp)
|
|
{
|
|
lwp->suspended--;
|
|
|
|
if (lwp->suspended < 0)
|
|
{
|
|
struct thread_info *thread = get_lwp_thread (lwp);
|
|
|
|
internal_error (__FILE__, __LINE__,
|
|
"unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread),
|
|
lwp->suspended);
|
|
}
|
|
}
|
|
|
|
/* This function should only be called if the LWP got a SIGTRAP.
|
|
|
|
Handle any tracepoint steps or hits. Return true if a tracepoint
|
|
event was handled, 0 otherwise. */
|
|
|
|
static int
|
|
handle_tracepoints (struct lwp_info *lwp)
|
|
{
|
|
struct thread_info *tinfo = get_lwp_thread (lwp);
|
|
int tpoint_related_event = 0;
|
|
|
|
gdb_assert (lwp->suspended == 0);
|
|
|
|
/* If this tracepoint hit causes a tracing stop, we'll immediately
|
|
uninsert tracepoints. To do this, we temporarily pause all
|
|
threads, unpatch away, and then unpause threads. We need to make
|
|
sure the unpausing doesn't resume LWP too. */
|
|
lwp_suspended_inc (lwp);
|
|
|
|
/* And we need to be sure that any all-threads-stopping doesn't try
|
|
to move threads out of the jump pads, as it could deadlock the
|
|
inferior (LWP could be in the jump pad, maybe even holding the
|
|
lock.) */
|
|
|
|
/* Do any necessary step collect actions. */
|
|
tpoint_related_event |= tracepoint_finished_step (tinfo, lwp->stop_pc);
|
|
|
|
tpoint_related_event |= handle_tracepoint_bkpts (tinfo, lwp->stop_pc);
|
|
|
|
/* See if we just hit a tracepoint and do its main collect
|
|
actions. */
|
|
tpoint_related_event |= tracepoint_was_hit (tinfo, lwp->stop_pc);
|
|
|
|
lwp_suspended_decr (lwp);
|
|
|
|
gdb_assert (lwp->suspended == 0);
|
|
gdb_assert (!stabilizing_threads
|
|
|| (lwp->collecting_fast_tracepoint
|
|
!= fast_tpoint_collect_result::not_collecting));
|
|
|
|
if (tpoint_related_event)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("got a tracepoint event\n");
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Convenience wrapper. Returns information about LWP's fast tracepoint
|
|
collection status. */
|
|
|
|
static fast_tpoint_collect_result
|
|
linux_fast_tracepoint_collecting (struct lwp_info *lwp,
|
|
struct fast_tpoint_collect_status *status)
|
|
{
|
|
CORE_ADDR thread_area;
|
|
struct thread_info *thread = get_lwp_thread (lwp);
|
|
|
|
if (the_low_target.get_thread_area == NULL)
|
|
return fast_tpoint_collect_result::not_collecting;
|
|
|
|
/* Get the thread area address. This is used to recognize which
|
|
thread is which when tracing with the in-process agent library.
|
|
We don't read anything from the address, and treat it as opaque;
|
|
it's the address itself that we assume is unique per-thread. */
|
|
if ((*the_low_target.get_thread_area) (lwpid_of (thread), &thread_area) == -1)
|
|
return fast_tpoint_collect_result::not_collecting;
|
|
|
|
return fast_tracepoint_collecting (thread_area, lwp->stop_pc, status);
|
|
}
|
|
|
|
/* The reason we resume in the caller, is because we want to be able
|
|
to pass lwp->status_pending as WSTAT, and we need to clear
|
|
status_pending_p before resuming, otherwise, linux_resume_one_lwp
|
|
refuses to resume. */
|
|
|
|
static int
|
|
maybe_move_out_of_jump_pad (struct lwp_info *lwp, int *wstat)
|
|
{
|
|
struct thread_info *saved_thread;
|
|
|
|
saved_thread = current_thread;
|
|
current_thread = get_lwp_thread (lwp);
|
|
|
|
if ((wstat == NULL
|
|
|| (WIFSTOPPED (*wstat) && WSTOPSIG (*wstat) != SIGTRAP))
|
|
&& supports_fast_tracepoints ()
|
|
&& agent_loaded_p ())
|
|
{
|
|
struct fast_tpoint_collect_status status;
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Checking whether LWP %ld needs to move out of the "
|
|
"jump pad.\n",
|
|
lwpid_of (current_thread));
|
|
|
|
fast_tpoint_collect_result r
|
|
= linux_fast_tracepoint_collecting (lwp, &status);
|
|
|
|
if (wstat == NULL
|
|
|| (WSTOPSIG (*wstat) != SIGILL
|
|
&& WSTOPSIG (*wstat) != SIGFPE
|
|
&& WSTOPSIG (*wstat) != SIGSEGV
|
|
&& WSTOPSIG (*wstat) != SIGBUS))
|
|
{
|
|
lwp->collecting_fast_tracepoint = r;
|
|
|
|
if (r != fast_tpoint_collect_result::not_collecting)
|
|
{
|
|
if (r == fast_tpoint_collect_result::before_insn
|
|
&& lwp->exit_jump_pad_bkpt == NULL)
|
|
{
|
|
/* Haven't executed the original instruction yet.
|
|
Set breakpoint there, and wait till it's hit,
|
|
then single-step until exiting the jump pad. */
|
|
lwp->exit_jump_pad_bkpt
|
|
= set_breakpoint_at (status.adjusted_insn_addr, NULL);
|
|
}
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Checking whether LWP %ld needs to move out of "
|
|
"the jump pad...it does\n",
|
|
lwpid_of (current_thread));
|
|
current_thread = saved_thread;
|
|
|
|
return 1;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* If we get a synchronous signal while collecting, *and*
|
|
while executing the (relocated) original instruction,
|
|
reset the PC to point at the tpoint address, before
|
|
reporting to GDB. Otherwise, it's an IPA lib bug: just
|
|
report the signal to GDB, and pray for the best. */
|
|
|
|
lwp->collecting_fast_tracepoint
|
|
= fast_tpoint_collect_result::not_collecting;
|
|
|
|
if (r != fast_tpoint_collect_result::not_collecting
|
|
&& (status.adjusted_insn_addr <= lwp->stop_pc
|
|
&& lwp->stop_pc < status.adjusted_insn_addr_end))
|
|
{
|
|
siginfo_t info;
|
|
struct regcache *regcache;
|
|
|
|
/* The si_addr on a few signals references the address
|
|
of the faulting instruction. Adjust that as
|
|
well. */
|
|
if ((WSTOPSIG (*wstat) == SIGILL
|
|
|| WSTOPSIG (*wstat) == SIGFPE
|
|
|| WSTOPSIG (*wstat) == SIGBUS
|
|
|| WSTOPSIG (*wstat) == SIGSEGV)
|
|
&& ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
|
|
(PTRACE_TYPE_ARG3) 0, &info) == 0
|
|
/* Final check just to make sure we don't clobber
|
|
the siginfo of non-kernel-sent signals. */
|
|
&& (uintptr_t) info.si_addr == lwp->stop_pc)
|
|
{
|
|
info.si_addr = (void *) (uintptr_t) status.tpoint_addr;
|
|
ptrace (PTRACE_SETSIGINFO, lwpid_of (current_thread),
|
|
(PTRACE_TYPE_ARG3) 0, &info);
|
|
}
|
|
|
|
regcache = get_thread_regcache (current_thread, 1);
|
|
(*the_low_target.set_pc) (regcache, status.tpoint_addr);
|
|
lwp->stop_pc = status.tpoint_addr;
|
|
|
|
/* Cancel any fast tracepoint lock this thread was
|
|
holding. */
|
|
force_unlock_trace_buffer ();
|
|
}
|
|
|
|
if (lwp->exit_jump_pad_bkpt != NULL)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
|
|
"stopping all threads momentarily.\n");
|
|
|
|
stop_all_lwps (1, lwp);
|
|
|
|
delete_breakpoint (lwp->exit_jump_pad_bkpt);
|
|
lwp->exit_jump_pad_bkpt = NULL;
|
|
|
|
unstop_all_lwps (1, lwp);
|
|
|
|
gdb_assert (lwp->suspended >= 0);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Checking whether LWP %ld needs to move out of the "
|
|
"jump pad...no\n",
|
|
lwpid_of (current_thread));
|
|
|
|
current_thread = saved_thread;
|
|
return 0;
|
|
}
|
|
|
|
/* Enqueue one signal in the "signals to report later when out of the
|
|
jump pad" list. */
|
|
|
|
static void
|
|
enqueue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
|
|
{
|
|
struct pending_signals *p_sig;
|
|
struct thread_info *thread = get_lwp_thread (lwp);
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Deferring signal %d for LWP %ld.\n",
|
|
WSTOPSIG (*wstat), lwpid_of (thread));
|
|
|
|
if (debug_threads)
|
|
{
|
|
struct pending_signals *sig;
|
|
|
|
for (sig = lwp->pending_signals_to_report;
|
|
sig != NULL;
|
|
sig = sig->prev)
|
|
debug_printf (" Already queued %d\n",
|
|
sig->signal);
|
|
|
|
debug_printf (" (no more currently queued signals)\n");
|
|
}
|
|
|
|
/* Don't enqueue non-RT signals if they are already in the deferred
|
|
queue. (SIGSTOP being the easiest signal to see ending up here
|
|
twice) */
|
|
if (WSTOPSIG (*wstat) < __SIGRTMIN)
|
|
{
|
|
struct pending_signals *sig;
|
|
|
|
for (sig = lwp->pending_signals_to_report;
|
|
sig != NULL;
|
|
sig = sig->prev)
|
|
{
|
|
if (sig->signal == WSTOPSIG (*wstat))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Not requeuing already queued non-RT signal %d"
|
|
" for LWP %ld\n",
|
|
sig->signal,
|
|
lwpid_of (thread));
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
p_sig = XCNEW (struct pending_signals);
|
|
p_sig->prev = lwp->pending_signals_to_report;
|
|
p_sig->signal = WSTOPSIG (*wstat);
|
|
|
|
ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
|
|
&p_sig->info);
|
|
|
|
lwp->pending_signals_to_report = p_sig;
|
|
}
|
|
|
|
/* Dequeue one signal from the "signals to report later when out of
|
|
the jump pad" list. */
|
|
|
|
static int
|
|
dequeue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
|
|
{
|
|
struct thread_info *thread = get_lwp_thread (lwp);
|
|
|
|
if (lwp->pending_signals_to_report != NULL)
|
|
{
|
|
struct pending_signals **p_sig;
|
|
|
|
p_sig = &lwp->pending_signals_to_report;
|
|
while ((*p_sig)->prev != NULL)
|
|
p_sig = &(*p_sig)->prev;
|
|
|
|
*wstat = W_STOPCODE ((*p_sig)->signal);
|
|
if ((*p_sig)->info.si_signo != 0)
|
|
ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
|
|
&(*p_sig)->info);
|
|
free (*p_sig);
|
|
*p_sig = NULL;
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
|
|
WSTOPSIG (*wstat), lwpid_of (thread));
|
|
|
|
if (debug_threads)
|
|
{
|
|
struct pending_signals *sig;
|
|
|
|
for (sig = lwp->pending_signals_to_report;
|
|
sig != NULL;
|
|
sig = sig->prev)
|
|
debug_printf (" Still queued %d\n",
|
|
sig->signal);
|
|
|
|
debug_printf (" (no more queued signals)\n");
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Fetch the possibly triggered data watchpoint info and store it in
|
|
CHILD.
|
|
|
|
On some archs, like x86, that use debug registers to set
|
|
watchpoints, it's possible that the way to know which watched
|
|
address trapped, is to check the register that is used to select
|
|
which address to watch. Problem is, between setting the watchpoint
|
|
and reading back which data address trapped, the user may change
|
|
the set of watchpoints, and, as a consequence, GDB changes the
|
|
debug registers in the inferior. To avoid reading back a stale
|
|
stopped-data-address when that happens, we cache in LP the fact
|
|
that a watchpoint trapped, and the corresponding data address, as
|
|
soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
|
|
registers meanwhile, we have the cached data we can rely on. */
|
|
|
|
static int
|
|
check_stopped_by_watchpoint (struct lwp_info *child)
|
|
{
|
|
if (the_low_target.stopped_by_watchpoint != NULL)
|
|
{
|
|
struct thread_info *saved_thread;
|
|
|
|
saved_thread = current_thread;
|
|
current_thread = get_lwp_thread (child);
|
|
|
|
if (the_low_target.stopped_by_watchpoint ())
|
|
{
|
|
child->stop_reason = TARGET_STOPPED_BY_WATCHPOINT;
|
|
|
|
if (the_low_target.stopped_data_address != NULL)
|
|
child->stopped_data_address
|
|
= the_low_target.stopped_data_address ();
|
|
else
|
|
child->stopped_data_address = 0;
|
|
}
|
|
|
|
current_thread = saved_thread;
|
|
}
|
|
|
|
return child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
|
|
}
|
|
|
|
/* Return the ptrace options that we want to try to enable. */
|
|
|
|
static int
|
|
linux_low_ptrace_options (int attached)
|
|
{
|
|
int options = 0;
|
|
|
|
if (!attached)
|
|
options |= PTRACE_O_EXITKILL;
|
|
|
|
if (report_fork_events)
|
|
options |= PTRACE_O_TRACEFORK;
|
|
|
|
if (report_vfork_events)
|
|
options |= (PTRACE_O_TRACEVFORK | PTRACE_O_TRACEVFORKDONE);
|
|
|
|
if (report_exec_events)
|
|
options |= PTRACE_O_TRACEEXEC;
|
|
|
|
options |= PTRACE_O_TRACESYSGOOD;
|
|
|
|
return options;
|
|
}
|
|
|
|
/* Do low-level handling of the event, and check if we should go on
|
|
and pass it to caller code. Return the affected lwp if we are, or
|
|
NULL otherwise. */
|
|
|
|
static struct lwp_info *
|
|
linux_low_filter_event (int lwpid, int wstat)
|
|
{
|
|
struct lwp_info *child;
|
|
struct thread_info *thread;
|
|
int have_stop_pc = 0;
|
|
|
|
child = find_lwp_pid (pid_to_ptid (lwpid));
|
|
|
|
/* Check for stop events reported by a process we didn't already
|
|
know about - anything not already in our LWP list.
|
|
|
|
If we're expecting to receive stopped processes after
|
|
fork, vfork, and clone events, then we'll just add the
|
|
new one to our list and go back to waiting for the event
|
|
to be reported - the stopped process might be returned
|
|
from waitpid before or after the event is.
|
|
|
|
But note the case of a non-leader thread exec'ing after the
|
|
leader having exited, and gone from our lists (because
|
|
check_zombie_leaders deleted it). The non-leader thread
|
|
changes its tid to the tgid. */
|
|
|
|
if (WIFSTOPPED (wstat) && child == NULL && WSTOPSIG (wstat) == SIGTRAP
|
|
&& linux_ptrace_get_extended_event (wstat) == PTRACE_EVENT_EXEC)
|
|
{
|
|
ptid_t child_ptid;
|
|
|
|
/* A multi-thread exec after we had seen the leader exiting. */
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("LLW: Re-adding thread group leader LWP %d"
|
|
"after exec.\n", lwpid);
|
|
}
|
|
|
|
child_ptid = ptid_build (lwpid, lwpid, 0);
|
|
child = add_lwp (child_ptid);
|
|
child->stopped = 1;
|
|
current_thread = child->thread;
|
|
}
|
|
|
|
/* If we didn't find a process, one of two things presumably happened:
|
|
- A process we started and then detached from has exited. Ignore it.
|
|
- A process we are controlling has forked and the new child's stop
|
|
was reported to us by the kernel. Save its PID. */
|
|
if (child == NULL && WIFSTOPPED (wstat))
|
|
{
|
|
add_to_pid_list (&stopped_pids, lwpid, wstat);
|
|
return NULL;
|
|
}
|
|
else if (child == NULL)
|
|
return NULL;
|
|
|
|
thread = get_lwp_thread (child);
|
|
|
|
child->stopped = 1;
|
|
|
|
child->last_status = wstat;
|
|
|
|
/* Check if the thread has exited. */
|
|
if ((WIFEXITED (wstat) || WIFSIGNALED (wstat)))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("LLFE: %d exited.\n", lwpid);
|
|
|
|
if (finish_step_over (child))
|
|
{
|
|
/* Unsuspend all other LWPs, and set them back running again. */
|
|
unsuspend_all_lwps (child);
|
|
}
|
|
|
|
/* If there is at least one more LWP, then the exit signal was
|
|
not the end of the debugged application and should be
|
|
ignored, unless GDB wants to hear about thread exits. */
|
|
if (report_thread_events
|
|
|| last_thread_of_process_p (pid_of (thread)))
|
|
{
|
|
/* Since events are serialized to GDB core, and we can't
|
|
report this one right now. Leave the status pending for
|
|
the next time we're able to report it. */
|
|
mark_lwp_dead (child, wstat);
|
|
return child;
|
|
}
|
|
else
|
|
{
|
|
delete_lwp (child);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
gdb_assert (WIFSTOPPED (wstat));
|
|
|
|
if (WIFSTOPPED (wstat))
|
|
{
|
|
struct process_info *proc;
|
|
|
|
/* Architecture-specific setup after inferior is running. */
|
|
proc = find_process_pid (pid_of (thread));
|
|
if (proc->tdesc == NULL)
|
|
{
|
|
if (proc->attached)
|
|
{
|
|
/* This needs to happen after we have attached to the
|
|
inferior and it is stopped for the first time, but
|
|
before we access any inferior registers. */
|
|
linux_arch_setup_thread (thread);
|
|
}
|
|
else
|
|
{
|
|
/* The process is started, but GDBserver will do
|
|
architecture-specific setup after the program stops at
|
|
the first instruction. */
|
|
child->status_pending_p = 1;
|
|
child->status_pending = wstat;
|
|
return child;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (WIFSTOPPED (wstat) && child->must_set_ptrace_flags)
|
|
{
|
|
struct process_info *proc = find_process_pid (pid_of (thread));
|
|
int options = linux_low_ptrace_options (proc->attached);
|
|
|
|
linux_enable_event_reporting (lwpid, options);
|
|
child->must_set_ptrace_flags = 0;
|
|
}
|
|
|
|
/* Always update syscall_state, even if it will be filtered later. */
|
|
if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SYSCALL_SIGTRAP)
|
|
{
|
|
child->syscall_state
|
|
= (child->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY
|
|
? TARGET_WAITKIND_SYSCALL_RETURN
|
|
: TARGET_WAITKIND_SYSCALL_ENTRY);
|
|
}
|
|
else
|
|
{
|
|
/* Almost all other ptrace-stops are known to be outside of system
|
|
calls, with further exceptions in handle_extended_wait. */
|
|
child->syscall_state = TARGET_WAITKIND_IGNORE;
|
|
}
|
|
|
|
/* Be careful to not overwrite stop_pc until save_stop_reason is
|
|
called. */
|
|
if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGTRAP
|
|
&& linux_is_extended_waitstatus (wstat))
|
|
{
|
|
child->stop_pc = get_pc (child);
|
|
if (handle_extended_wait (&child, wstat))
|
|
{
|
|
/* The event has been handled, so just return without
|
|
reporting it. */
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
if (linux_wstatus_maybe_breakpoint (wstat))
|
|
{
|
|
if (save_stop_reason (child))
|
|
have_stop_pc = 1;
|
|
}
|
|
|
|
if (!have_stop_pc)
|
|
child->stop_pc = get_pc (child);
|
|
|
|
if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGSTOP
|
|
&& child->stop_expected)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Expected stop.\n");
|
|
child->stop_expected = 0;
|
|
|
|
if (thread->last_resume_kind == resume_stop)
|
|
{
|
|
/* We want to report the stop to the core. Treat the
|
|
SIGSTOP as a normal event. */
|
|
if (debug_threads)
|
|
debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
|
|
target_pid_to_str (ptid_of (thread)));
|
|
}
|
|
else if (stopping_threads != NOT_STOPPING_THREADS)
|
|
{
|
|
/* Stopping threads. We don't want this SIGSTOP to end up
|
|
pending. */
|
|
if (debug_threads)
|
|
debug_printf ("LLW: SIGSTOP caught for %s "
|
|
"while stopping threads.\n",
|
|
target_pid_to_str (ptid_of (thread)));
|
|
return NULL;
|
|
}
|
|
else
|
|
{
|
|
/* This is a delayed SIGSTOP. Filter out the event. */
|
|
if (debug_threads)
|
|
debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
|
|
child->stepping ? "step" : "continue",
|
|
target_pid_to_str (ptid_of (thread)));
|
|
|
|
linux_resume_one_lwp (child, child->stepping, 0, NULL);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
child->status_pending_p = 1;
|
|
child->status_pending = wstat;
|
|
return child;
|
|
}
|
|
|
|
/* Return true if THREAD is doing hardware single step. */
|
|
|
|
static int
|
|
maybe_hw_step (struct thread_info *thread)
|
|
{
|
|
if (can_hardware_single_step ())
|
|
return 1;
|
|
else
|
|
{
|
|
/* GDBserver must insert single-step breakpoint for software
|
|
single step. */
|
|
gdb_assert (has_single_step_breakpoints (thread));
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/* Resume LWPs that are currently stopped without any pending status
|
|
to report, but are resumed from the core's perspective. */
|
|
|
|
static void
|
|
resume_stopped_resumed_lwps (thread_info *thread)
|
|
{
|
|
struct lwp_info *lp = get_thread_lwp (thread);
|
|
|
|
if (lp->stopped
|
|
&& !lp->suspended
|
|
&& !lp->status_pending_p
|
|
&& thread->last_status.kind == TARGET_WAITKIND_IGNORE)
|
|
{
|
|
int step = 0;
|
|
|
|
if (thread->last_resume_kind == resume_step)
|
|
step = maybe_hw_step (thread);
|
|
|
|
if (debug_threads)
|
|
debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
|
|
target_pid_to_str (ptid_of (thread)),
|
|
paddress (lp->stop_pc),
|
|
step);
|
|
|
|
linux_resume_one_lwp (lp, step, GDB_SIGNAL_0, NULL);
|
|
}
|
|
}
|
|
|
|
/* Wait for an event from child(ren) WAIT_PTID, and return any that
|
|
match FILTER_PTID (leaving others pending). The PTIDs can be:
|
|
minus_one_ptid, to specify any child; a pid PTID, specifying all
|
|
lwps of a thread group; or a PTID representing a single lwp. Store
|
|
the stop status through the status pointer WSTAT. OPTIONS is
|
|
passed to the waitpid call. Return 0 if no event was found and
|
|
OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
|
|
was found. Return the PID of the stopped child otherwise. */
|
|
|
|
static int
|
|
linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
|
|
int *wstatp, int options)
|
|
{
|
|
struct thread_info *event_thread;
|
|
struct lwp_info *event_child, *requested_child;
|
|
sigset_t block_mask, prev_mask;
|
|
|
|
retry:
|
|
/* N.B. event_thread points to the thread_info struct that contains
|
|
event_child. Keep them in sync. */
|
|
event_thread = NULL;
|
|
event_child = NULL;
|
|
requested_child = NULL;
|
|
|
|
/* Check for a lwp with a pending status. */
|
|
|
|
if (ptid_equal (filter_ptid, minus_one_ptid) || ptid_is_pid (filter_ptid))
|
|
{
|
|
event_thread = find_thread_in_random ([&] (thread_info *thread)
|
|
{
|
|
return status_pending_p_callback (thread, filter_ptid);
|
|
});
|
|
|
|
if (event_thread != NULL)
|
|
event_child = get_thread_lwp (event_thread);
|
|
if (debug_threads && event_thread)
|
|
debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread));
|
|
}
|
|
else if (!ptid_equal (filter_ptid, null_ptid))
|
|
{
|
|
requested_child = find_lwp_pid (filter_ptid);
|
|
|
|
if (stopping_threads == NOT_STOPPING_THREADS
|
|
&& requested_child->status_pending_p
|
|
&& (requested_child->collecting_fast_tracepoint
|
|
!= fast_tpoint_collect_result::not_collecting))
|
|
{
|
|
enqueue_one_deferred_signal (requested_child,
|
|
&requested_child->status_pending);
|
|
requested_child->status_pending_p = 0;
|
|
requested_child->status_pending = 0;
|
|
linux_resume_one_lwp (requested_child, 0, 0, NULL);
|
|
}
|
|
|
|
if (requested_child->suspended
|
|
&& requested_child->status_pending_p)
|
|
{
|
|
internal_error (__FILE__, __LINE__,
|
|
"requesting an event out of a"
|
|
" suspended child?");
|
|
}
|
|
|
|
if (requested_child->status_pending_p)
|
|
{
|
|
event_child = requested_child;
|
|
event_thread = get_lwp_thread (event_child);
|
|
}
|
|
}
|
|
|
|
if (event_child != NULL)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Got an event from pending child %ld (%04x)\n",
|
|
lwpid_of (event_thread), event_child->status_pending);
|
|
*wstatp = event_child->status_pending;
|
|
event_child->status_pending_p = 0;
|
|
event_child->status_pending = 0;
|
|
current_thread = event_thread;
|
|
return lwpid_of (event_thread);
|
|
}
|
|
|
|
/* But if we don't find a pending event, we'll have to wait.
|
|
|
|
We only enter this loop if no process has a pending wait status.
|
|
Thus any action taken in response to a wait status inside this
|
|
loop is responding as soon as we detect the status, not after any
|
|
pending events. */
|
|
|
|
/* Make sure SIGCHLD is blocked until the sigsuspend below. Block
|
|
all signals while here. */
|
|
sigfillset (&block_mask);
|
|
sigprocmask (SIG_BLOCK, &block_mask, &prev_mask);
|
|
|
|
/* Always pull all events out of the kernel. We'll randomly select
|
|
an event LWP out of all that have events, to prevent
|
|
starvation. */
|
|
while (event_child == NULL)
|
|
{
|
|
pid_t ret = 0;
|
|
|
|
/* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
|
|
quirks:
|
|
|
|
- If the thread group leader exits while other threads in the
|
|
thread group still exist, waitpid(TGID, ...) hangs. That
|
|
waitpid won't return an exit status until the other threads
|
|
in the group are reaped.
|
|
|
|
- When a non-leader thread execs, that thread just vanishes
|
|
without reporting an exit (so we'd hang if we waited for it
|
|
explicitly in that case). The exec event is reported to
|
|
the TGID pid. */
|
|
errno = 0;
|
|
ret = my_waitpid (-1, wstatp, options | WNOHANG);
|
|
|
|
if (debug_threads)
|
|
debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
|
|
ret, errno ? strerror (errno) : "ERRNO-OK");
|
|
|
|
if (ret > 0)
|
|
{
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("LLW: waitpid %ld received %s\n",
|
|
(long) ret, status_to_str (*wstatp));
|
|
}
|
|
|
|
/* Filter all events. IOW, leave all events pending. We'll
|
|
randomly select an event LWP out of all that have events
|
|
below. */
|
|
linux_low_filter_event (ret, *wstatp);
|
|
/* Retry until nothing comes out of waitpid. A single
|
|
SIGCHLD can indicate more than one child stopped. */
|
|
continue;
|
|
}
|
|
|
|
/* Now that we've pulled all events out of the kernel, resume
|
|
LWPs that don't have an interesting event to report. */
|
|
if (stopping_threads == NOT_STOPPING_THREADS)
|
|
for_each_thread (resume_stopped_resumed_lwps);
|
|
|
|
/* ... and find an LWP with a status to report to the core, if
|
|
any. */
|
|
event_thread = find_thread_in_random ([&] (thread_info *thread)
|
|
{
|
|
return status_pending_p_callback (thread, filter_ptid);
|
|
});
|
|
|
|
if (event_thread != NULL)
|
|
{
|
|
event_child = get_thread_lwp (event_thread);
|
|
*wstatp = event_child->status_pending;
|
|
event_child->status_pending_p = 0;
|
|
event_child->status_pending = 0;
|
|
break;
|
|
}
|
|
|
|
/* Check for zombie thread group leaders. Those can't be reaped
|
|
until all other threads in the thread group are. */
|
|
check_zombie_leaders ();
|
|
|
|
auto not_stopped = [&] (thread_info *thread)
|
|
{
|
|
return not_stopped_callback (thread, wait_ptid);
|
|
};
|
|
|
|
/* If there are no resumed children left in the set of LWPs we
|
|
want to wait for, bail. We can't just block in
|
|
waitpid/sigsuspend, because lwps might have been left stopped
|
|
in trace-stop state, and we'd be stuck forever waiting for
|
|
their status to change (which would only happen if we resumed
|
|
them). Even if WNOHANG is set, this return code is preferred
|
|
over 0 (below), as it is more detailed. */
|
|
if (find_thread (not_stopped) == NULL)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("LLW: exit (no unwaited-for LWP)\n");
|
|
sigprocmask (SIG_SETMASK, &prev_mask, NULL);
|
|
return -1;
|
|
}
|
|
|
|
/* No interesting event to report to the caller. */
|
|
if ((options & WNOHANG))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("WNOHANG set, no event found\n");
|
|
|
|
sigprocmask (SIG_SETMASK, &prev_mask, NULL);
|
|
return 0;
|
|
}
|
|
|
|
/* Block until we get an event reported with SIGCHLD. */
|
|
if (debug_threads)
|
|
debug_printf ("sigsuspend'ing\n");
|
|
|
|
sigsuspend (&prev_mask);
|
|
sigprocmask (SIG_SETMASK, &prev_mask, NULL);
|
|
goto retry;
|
|
}
|
|
|
|
sigprocmask (SIG_SETMASK, &prev_mask, NULL);
|
|
|
|
current_thread = event_thread;
|
|
|
|
return lwpid_of (event_thread);
|
|
}
|
|
|
|
/* Wait for an event from child(ren) PTID. PTIDs can be:
|
|
minus_one_ptid, to specify any child; a pid PTID, specifying all
|
|
lwps of a thread group; or a PTID representing a single lwp. Store
|
|
the stop status through the status pointer WSTAT. OPTIONS is
|
|
passed to the waitpid call. Return 0 if no event was found and
|
|
OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
|
|
was found. Return the PID of the stopped child otherwise. */
|
|
|
|
static int
|
|
linux_wait_for_event (ptid_t ptid, int *wstatp, int options)
|
|
{
|
|
return linux_wait_for_event_filtered (ptid, ptid, wstatp, options);
|
|
}
|
|
|
|
/* Select one LWP out of those that have events pending. */
|
|
|
|
static void
|
|
select_event_lwp (struct lwp_info **orig_lp)
|
|
{
|
|
int random_selector;
|
|
struct thread_info *event_thread = NULL;
|
|
|
|
/* In all-stop, give preference to the LWP that is being
|
|
single-stepped. There will be at most one, and it's the LWP that
|
|
the core is most interested in. If we didn't do this, then we'd
|
|
have to handle pending step SIGTRAPs somehow in case the core
|
|
later continues the previously-stepped thread, otherwise we'd
|
|
report the pending SIGTRAP, and the core, not having stepped the
|
|
thread, wouldn't understand what the trap was for, and therefore
|
|
would report it to the user as a random signal. */
|
|
if (!non_stop)
|
|
{
|
|
event_thread = find_thread ([] (thread_info *thread)
|
|
{
|
|
lwp_info *lp = get_thread_lwp (thread);
|
|
|
|
return (thread->last_status.kind == TARGET_WAITKIND_IGNORE
|
|
&& thread->last_resume_kind == resume_step
|
|
&& lp->status_pending_p);
|
|
});
|
|
|
|
if (event_thread != NULL)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("SEL: Select single-step %s\n",
|
|
target_pid_to_str (ptid_of (event_thread)));
|
|
}
|
|
}
|
|
if (event_thread == NULL)
|
|
{
|
|
/* No single-stepping LWP. Select one at random, out of those
|
|
which have had events. */
|
|
|
|
/* First see how many events we have. */
|
|
int num_events = 0;
|
|
for_each_thread ([&] (thread_info *thread)
|
|
{
|
|
lwp_info *lp = get_thread_lwp (thread);
|
|
|
|
/* Count only resumed LWPs that have an event pending. */
|
|
if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
|
|
&& lp->status_pending_p)
|
|
num_events++;
|
|
});
|
|
gdb_assert (num_events > 0);
|
|
|
|
/* Now randomly pick a LWP out of those that have had
|
|
events. */
|
|
random_selector = (int)
|
|
((num_events * (double) rand ()) / (RAND_MAX + 1.0));
|
|
|
|
if (debug_threads && num_events > 1)
|
|
debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
|
|
num_events, random_selector);
|
|
|
|
event_thread = find_thread ([&] (thread_info *thread)
|
|
{
|
|
lwp_info *lp = get_thread_lwp (thread);
|
|
|
|
/* Select only resumed LWPs that have an event pending. */
|
|
if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
|
|
&& lp->status_pending_p)
|
|
if (random_selector-- == 0)
|
|
return true;
|
|
|
|
return false;
|
|
});
|
|
}
|
|
|
|
if (event_thread != NULL)
|
|
{
|
|
struct lwp_info *event_lp = get_thread_lwp (event_thread);
|
|
|
|
/* Switch the event LWP. */
|
|
*orig_lp = event_lp;
|
|
}
|
|
}
|
|
|
|
/* Decrement the suspend count of all LWPs, except EXCEPT, if non
|
|
NULL. */
|
|
|
|
static void
|
|
unsuspend_all_lwps (struct lwp_info *except)
|
|
{
|
|
for_each_thread ([&] (thread_info *thread)
|
|
{
|
|
lwp_info *lwp = get_thread_lwp (thread);
|
|
|
|
if (lwp != except)
|
|
lwp_suspended_decr (lwp);
|
|
});
|
|
}
|
|
|
|
static void move_out_of_jump_pad_callback (thread_info *thread);
|
|
static bool stuck_in_jump_pad_callback (thread_info *thread);
|
|
static bool lwp_running (thread_info *thread);
|
|
static ptid_t linux_wait_1 (ptid_t ptid,
|
|
struct target_waitstatus *ourstatus,
|
|
int target_options);
|
|
|
|
/* Stabilize threads (move out of jump pads).
|
|
|
|
If a thread is midway collecting a fast tracepoint, we need to
|
|
finish the collection and move it out of the jump pad before
|
|
reporting the signal.
|
|
|
|
This avoids recursion while collecting (when a signal arrives
|
|
midway, and the signal handler itself collects), which would trash
|
|
the trace buffer. In case the user set a breakpoint in a signal
|
|
handler, this avoids the backtrace showing the jump pad, etc..
|
|
Most importantly, there are certain things we can't do safely if
|
|
threads are stopped in a jump pad (or in its callee's). For
|
|
example:
|
|
|
|
- starting a new trace run. A thread still collecting the
|
|
previous run, could trash the trace buffer when resumed. The trace
|
|
buffer control structures would have been reset but the thread had
|
|
no way to tell. The thread could even midway memcpy'ing to the
|
|
buffer, which would mean that when resumed, it would clobber the
|
|
trace buffer that had been set for a new run.
|
|
|
|
- we can't rewrite/reuse the jump pads for new tracepoints
|
|
safely. Say you do tstart while a thread is stopped midway while
|
|
collecting. When the thread is later resumed, it finishes the
|
|
collection, and returns to the jump pad, to execute the original
|
|
instruction that was under the tracepoint jump at the time the
|
|
older run had been started. If the jump pad had been rewritten
|
|
since for something else in the new run, the thread would now
|
|
execute the wrong / random instructions. */
|
|
|
|
static void
|
|
linux_stabilize_threads (void)
|
|
{
|
|
thread_info *thread_stuck = find_thread (stuck_in_jump_pad_callback);
|
|
|
|
if (thread_stuck != NULL)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
|
|
lwpid_of (thread_stuck));
|
|
return;
|
|
}
|
|
|
|
thread_info *saved_thread = current_thread;
|
|
|
|
stabilizing_threads = 1;
|
|
|
|
/* Kick 'em all. */
|
|
for_each_thread (move_out_of_jump_pad_callback);
|
|
|
|
/* Loop until all are stopped out of the jump pads. */
|
|
while (find_thread (lwp_running) != NULL)
|
|
{
|
|
struct target_waitstatus ourstatus;
|
|
struct lwp_info *lwp;
|
|
int wstat;
|
|
|
|
/* Note that we go through the full wait even loop. While
|
|
moving threads out of jump pad, we need to be able to step
|
|
over internal breakpoints and such. */
|
|
linux_wait_1 (minus_one_ptid, &ourstatus, 0);
|
|
|
|
if (ourstatus.kind == TARGET_WAITKIND_STOPPED)
|
|
{
|
|
lwp = get_thread_lwp (current_thread);
|
|
|
|
/* Lock it. */
|
|
lwp_suspended_inc (lwp);
|
|
|
|
if (ourstatus.value.sig != GDB_SIGNAL_0
|
|
|| current_thread->last_resume_kind == resume_stop)
|
|
{
|
|
wstat = W_STOPCODE (gdb_signal_to_host (ourstatus.value.sig));
|
|
enqueue_one_deferred_signal (lwp, &wstat);
|
|
}
|
|
}
|
|
}
|
|
|
|
unsuspend_all_lwps (NULL);
|
|
|
|
stabilizing_threads = 0;
|
|
|
|
current_thread = saved_thread;
|
|
|
|
if (debug_threads)
|
|
{
|
|
thread_stuck = find_thread (stuck_in_jump_pad_callback);
|
|
|
|
if (thread_stuck != NULL)
|
|
debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
|
|
lwpid_of (thread_stuck));
|
|
}
|
|
}
|
|
|
|
/* Convenience function that is called when the kernel reports an
|
|
event that is not passed out to GDB. */
|
|
|
|
static ptid_t
|
|
ignore_event (struct target_waitstatus *ourstatus)
|
|
{
|
|
/* If we got an event, there may still be others, as a single
|
|
SIGCHLD can indicate more than one child stopped. This forces
|
|
another target_wait call. */
|
|
async_file_mark ();
|
|
|
|
ourstatus->kind = TARGET_WAITKIND_IGNORE;
|
|
return null_ptid;
|
|
}
|
|
|
|
/* Convenience function that is called when the kernel reports an exit
|
|
event. This decides whether to report the event to GDB as a
|
|
process exit event, a thread exit event, or to suppress the
|
|
event. */
|
|
|
|
static ptid_t
|
|
filter_exit_event (struct lwp_info *event_child,
|
|
struct target_waitstatus *ourstatus)
|
|
{
|
|
struct thread_info *thread = get_lwp_thread (event_child);
|
|
ptid_t ptid = ptid_of (thread);
|
|
|
|
if (!last_thread_of_process_p (pid_of (thread)))
|
|
{
|
|
if (report_thread_events)
|
|
ourstatus->kind = TARGET_WAITKIND_THREAD_EXITED;
|
|
else
|
|
ourstatus->kind = TARGET_WAITKIND_IGNORE;
|
|
|
|
delete_lwp (event_child);
|
|
}
|
|
return ptid;
|
|
}
|
|
|
|
/* Returns 1 if GDB is interested in any event_child syscalls. */
|
|
|
|
static int
|
|
gdb_catching_syscalls_p (struct lwp_info *event_child)
|
|
{
|
|
struct thread_info *thread = get_lwp_thread (event_child);
|
|
struct process_info *proc = get_thread_process (thread);
|
|
|
|
return !proc->syscalls_to_catch.empty ();
|
|
}
|
|
|
|
/* Returns 1 if GDB is interested in the event_child syscall.
|
|
Only to be called when stopped reason is SYSCALL_SIGTRAP. */
|
|
|
|
static int
|
|
gdb_catch_this_syscall_p (struct lwp_info *event_child)
|
|
{
|
|
int sysno;
|
|
struct thread_info *thread = get_lwp_thread (event_child);
|
|
struct process_info *proc = get_thread_process (thread);
|
|
|
|
if (proc->syscalls_to_catch.empty ())
|
|
return 0;
|
|
|
|
if (proc->syscalls_to_catch[0] == ANY_SYSCALL)
|
|
return 1;
|
|
|
|
get_syscall_trapinfo (event_child, &sysno);
|
|
|
|
for (int iter : proc->syscalls_to_catch)
|
|
if (iter == sysno)
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Wait for process, returns status. */
|
|
|
|
static ptid_t
|
|
linux_wait_1 (ptid_t ptid,
|
|
struct target_waitstatus *ourstatus, int target_options)
|
|
{
|
|
int w;
|
|
struct lwp_info *event_child;
|
|
int options;
|
|
int pid;
|
|
int step_over_finished;
|
|
int bp_explains_trap;
|
|
int maybe_internal_trap;
|
|
int report_to_gdb;
|
|
int trace_event;
|
|
int in_step_range;
|
|
int any_resumed;
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_enter ();
|
|
debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid));
|
|
}
|
|
|
|
/* Translate generic target options into linux options. */
|
|
options = __WALL;
|
|
if (target_options & TARGET_WNOHANG)
|
|
options |= WNOHANG;
|
|
|
|
bp_explains_trap = 0;
|
|
trace_event = 0;
|
|
in_step_range = 0;
|
|
ourstatus->kind = TARGET_WAITKIND_IGNORE;
|
|
|
|
auto status_pending_p_any = [&] (thread_info *thread)
|
|
{
|
|
return status_pending_p_callback (thread, minus_one_ptid);
|
|
};
|
|
|
|
auto not_stopped = [&] (thread_info *thread)
|
|
{
|
|
return not_stopped_callback (thread, minus_one_ptid);
|
|
};
|
|
|
|
/* Find a resumed LWP, if any. */
|
|
if (find_thread (status_pending_p_any) != NULL)
|
|
any_resumed = 1;
|
|
else if (find_thread (not_stopped) != NULL)
|
|
any_resumed = 1;
|
|
else
|
|
any_resumed = 0;
|
|
|
|
if (ptid_equal (step_over_bkpt, null_ptid))
|
|
pid = linux_wait_for_event (ptid, &w, options);
|
|
else
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
|
|
target_pid_to_str (step_over_bkpt));
|
|
pid = linux_wait_for_event (step_over_bkpt, &w, options & ~WNOHANG);
|
|
}
|
|
|
|
if (pid == 0 || (pid == -1 && !any_resumed))
|
|
{
|
|
gdb_assert (target_options & TARGET_WNOHANG);
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("linux_wait_1 ret = null_ptid, "
|
|
"TARGET_WAITKIND_IGNORE\n");
|
|
debug_exit ();
|
|
}
|
|
|
|
ourstatus->kind = TARGET_WAITKIND_IGNORE;
|
|
return null_ptid;
|
|
}
|
|
else if (pid == -1)
|
|
{
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("linux_wait_1 ret = null_ptid, "
|
|
"TARGET_WAITKIND_NO_RESUMED\n");
|
|
debug_exit ();
|
|
}
|
|
|
|
ourstatus->kind = TARGET_WAITKIND_NO_RESUMED;
|
|
return null_ptid;
|
|
}
|
|
|
|
event_child = get_thread_lwp (current_thread);
|
|
|
|
/* linux_wait_for_event only returns an exit status for the last
|
|
child of a process. Report it. */
|
|
if (WIFEXITED (w) || WIFSIGNALED (w))
|
|
{
|
|
if (WIFEXITED (w))
|
|
{
|
|
ourstatus->kind = TARGET_WAITKIND_EXITED;
|
|
ourstatus->value.integer = WEXITSTATUS (w);
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("linux_wait_1 ret = %s, exited with "
|
|
"retcode %d\n",
|
|
target_pid_to_str (ptid_of (current_thread)),
|
|
WEXITSTATUS (w));
|
|
debug_exit ();
|
|
}
|
|
}
|
|
else
|
|
{
|
|
ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
|
|
ourstatus->value.sig = gdb_signal_from_host (WTERMSIG (w));
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("linux_wait_1 ret = %s, terminated with "
|
|
"signal %d\n",
|
|
target_pid_to_str (ptid_of (current_thread)),
|
|
WTERMSIG (w));
|
|
debug_exit ();
|
|
}
|
|
}
|
|
|
|
if (ourstatus->kind == TARGET_WAITKIND_EXITED)
|
|
return filter_exit_event (event_child, ourstatus);
|
|
|
|
return ptid_of (current_thread);
|
|
}
|
|
|
|
/* If step-over executes a breakpoint instruction, in the case of a
|
|
hardware single step it means a gdb/gdbserver breakpoint had been
|
|
planted on top of a permanent breakpoint, in the case of a software
|
|
single step it may just mean that gdbserver hit the reinsert breakpoint.
|
|
The PC has been adjusted by save_stop_reason to point at
|
|
the breakpoint address.
|
|
So in the case of the hardware single step advance the PC manually
|
|
past the breakpoint and in the case of software single step advance only
|
|
if it's not the single_step_breakpoint we are hitting.
|
|
This avoids that a program would keep trapping a permanent breakpoint
|
|
forever. */
|
|
if (!ptid_equal (step_over_bkpt, null_ptid)
|
|
&& event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
|
|
&& (event_child->stepping
|
|
|| !single_step_breakpoint_inserted_here (event_child->stop_pc)))
|
|
{
|
|
int increment_pc = 0;
|
|
int breakpoint_kind = 0;
|
|
CORE_ADDR stop_pc = event_child->stop_pc;
|
|
|
|
breakpoint_kind =
|
|
the_target->breakpoint_kind_from_current_state (&stop_pc);
|
|
the_target->sw_breakpoint_from_kind (breakpoint_kind, &increment_pc);
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("step-over for %s executed software breakpoint\n",
|
|
target_pid_to_str (ptid_of (current_thread)));
|
|
}
|
|
|
|
if (increment_pc != 0)
|
|
{
|
|
struct regcache *regcache
|
|
= get_thread_regcache (current_thread, 1);
|
|
|
|
event_child->stop_pc += increment_pc;
|
|
(*the_low_target.set_pc) (regcache, event_child->stop_pc);
|
|
|
|
if (!(*the_low_target.breakpoint_at) (event_child->stop_pc))
|
|
event_child->stop_reason = TARGET_STOPPED_BY_NO_REASON;
|
|
}
|
|
}
|
|
|
|
/* If this event was not handled before, and is not a SIGTRAP, we
|
|
report it. SIGILL and SIGSEGV are also treated as traps in case
|
|
a breakpoint is inserted at the current PC. If this target does
|
|
not support internal breakpoints at all, we also report the
|
|
SIGTRAP without further processing; it's of no concern to us. */
|
|
maybe_internal_trap
|
|
= (supports_breakpoints ()
|
|
&& (WSTOPSIG (w) == SIGTRAP
|
|
|| ((WSTOPSIG (w) == SIGILL
|
|
|| WSTOPSIG (w) == SIGSEGV)
|
|
&& (*the_low_target.breakpoint_at) (event_child->stop_pc))));
|
|
|
|
if (maybe_internal_trap)
|
|
{
|
|
/* Handle anything that requires bookkeeping before deciding to
|
|
report the event or continue waiting. */
|
|
|
|
/* First check if we can explain the SIGTRAP with an internal
|
|
breakpoint, or if we should possibly report the event to GDB.
|
|
Do this before anything that may remove or insert a
|
|
breakpoint. */
|
|
bp_explains_trap = breakpoint_inserted_here (event_child->stop_pc);
|
|
|
|
/* We have a SIGTRAP, possibly a step-over dance has just
|
|
finished. If so, tweak the state machine accordingly,
|
|
reinsert breakpoints and delete any single-step
|
|
breakpoints. */
|
|
step_over_finished = finish_step_over (event_child);
|
|
|
|
/* Now invoke the callbacks of any internal breakpoints there. */
|
|
check_breakpoints (event_child->stop_pc);
|
|
|
|
/* Handle tracepoint data collecting. This may overflow the
|
|
trace buffer, and cause a tracing stop, removing
|
|
breakpoints. */
|
|
trace_event = handle_tracepoints (event_child);
|
|
|
|
if (bp_explains_trap)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Hit a gdbserver breakpoint.\n");
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* We have some other signal, possibly a step-over dance was in
|
|
progress, and it should be cancelled too. */
|
|
step_over_finished = finish_step_over (event_child);
|
|
}
|
|
|
|
/* We have all the data we need. Either report the event to GDB, or
|
|
resume threads and keep waiting for more. */
|
|
|
|
/* If we're collecting a fast tracepoint, finish the collection and
|
|
move out of the jump pad before delivering a signal. See
|
|
linux_stabilize_threads. */
|
|
|
|
if (WIFSTOPPED (w)
|
|
&& WSTOPSIG (w) != SIGTRAP
|
|
&& supports_fast_tracepoints ()
|
|
&& agent_loaded_p ())
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Got signal %d for LWP %ld. Check if we need "
|
|
"to defer or adjust it.\n",
|
|
WSTOPSIG (w), lwpid_of (current_thread));
|
|
|
|
/* Allow debugging the jump pad itself. */
|
|
if (current_thread->last_resume_kind != resume_step
|
|
&& maybe_move_out_of_jump_pad (event_child, &w))
|
|
{
|
|
enqueue_one_deferred_signal (event_child, &w);
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
|
|
WSTOPSIG (w), lwpid_of (current_thread));
|
|
|
|
linux_resume_one_lwp (event_child, 0, 0, NULL);
|
|
|
|
if (debug_threads)
|
|
debug_exit ();
|
|
return ignore_event (ourstatus);
|
|
}
|
|
}
|
|
|
|
if (event_child->collecting_fast_tracepoint
|
|
!= fast_tpoint_collect_result::not_collecting)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
|
|
"Check if we're already there.\n",
|
|
lwpid_of (current_thread),
|
|
(int) event_child->collecting_fast_tracepoint);
|
|
|
|
trace_event = 1;
|
|
|
|
event_child->collecting_fast_tracepoint
|
|
= linux_fast_tracepoint_collecting (event_child, NULL);
|
|
|
|
if (event_child->collecting_fast_tracepoint
|
|
!= fast_tpoint_collect_result::before_insn)
|
|
{
|
|
/* No longer need this breakpoint. */
|
|
if (event_child->exit_jump_pad_bkpt != NULL)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("No longer need exit-jump-pad bkpt; removing it."
|
|
"stopping all threads momentarily.\n");
|
|
|
|
/* Other running threads could hit this breakpoint.
|
|
We don't handle moribund locations like GDB does,
|
|
instead we always pause all threads when removing
|
|
breakpoints, so that any step-over or
|
|
decr_pc_after_break adjustment is always taken
|
|
care of while the breakpoint is still
|
|
inserted. */
|
|
stop_all_lwps (1, event_child);
|
|
|
|
delete_breakpoint (event_child->exit_jump_pad_bkpt);
|
|
event_child->exit_jump_pad_bkpt = NULL;
|
|
|
|
unstop_all_lwps (1, event_child);
|
|
|
|
gdb_assert (event_child->suspended >= 0);
|
|
}
|
|
}
|
|
|
|
if (event_child->collecting_fast_tracepoint
|
|
== fast_tpoint_collect_result::not_collecting)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("fast tracepoint finished "
|
|
"collecting successfully.\n");
|
|
|
|
/* We may have a deferred signal to report. */
|
|
if (dequeue_one_deferred_signal (event_child, &w))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("dequeued one signal.\n");
|
|
}
|
|
else
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("no deferred signals.\n");
|
|
|
|
if (stabilizing_threads)
|
|
{
|
|
ourstatus->kind = TARGET_WAITKIND_STOPPED;
|
|
ourstatus->value.sig = GDB_SIGNAL_0;
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("linux_wait_1 ret = %s, stopped "
|
|
"while stabilizing threads\n",
|
|
target_pid_to_str (ptid_of (current_thread)));
|
|
debug_exit ();
|
|
}
|
|
|
|
return ptid_of (current_thread);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Check whether GDB would be interested in this event. */
|
|
|
|
/* Check if GDB is interested in this syscall. */
|
|
if (WIFSTOPPED (w)
|
|
&& WSTOPSIG (w) == SYSCALL_SIGTRAP
|
|
&& !gdb_catch_this_syscall_p (event_child))
|
|
{
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("Ignored syscall for LWP %ld.\n",
|
|
lwpid_of (current_thread));
|
|
}
|
|
|
|
linux_resume_one_lwp (event_child, event_child->stepping,
|
|
0, NULL);
|
|
|
|
if (debug_threads)
|
|
debug_exit ();
|
|
return ignore_event (ourstatus);
|
|
}
|
|
|
|
/* If GDB is not interested in this signal, don't stop other
|
|
threads, and don't report it to GDB. Just resume the inferior
|
|
right away. We do this for threading-related signals as well as
|
|
any that GDB specifically requested we ignore. But never ignore
|
|
SIGSTOP if we sent it ourselves, and do not ignore signals when
|
|
stepping - they may require special handling to skip the signal
|
|
handler. Also never ignore signals that could be caused by a
|
|
breakpoint. */
|
|
if (WIFSTOPPED (w)
|
|
&& current_thread->last_resume_kind != resume_step
|
|
&& (
|
|
#if defined (USE_THREAD_DB) && !defined (__ANDROID__)
|
|
(current_process ()->priv->thread_db != NULL
|
|
&& (WSTOPSIG (w) == __SIGRTMIN
|
|
|| WSTOPSIG (w) == __SIGRTMIN + 1))
|
|
||
|
|
#endif
|
|
(pass_signals[gdb_signal_from_host (WSTOPSIG (w))]
|
|
&& !(WSTOPSIG (w) == SIGSTOP
|
|
&& current_thread->last_resume_kind == resume_stop)
|
|
&& !linux_wstatus_maybe_breakpoint (w))))
|
|
{
|
|
siginfo_t info, *info_p;
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Ignored signal %d for LWP %ld.\n",
|
|
WSTOPSIG (w), lwpid_of (current_thread));
|
|
|
|
if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
|
|
(PTRACE_TYPE_ARG3) 0, &info) == 0)
|
|
info_p = &info;
|
|
else
|
|
info_p = NULL;
|
|
|
|
if (step_over_finished)
|
|
{
|
|
/* We cancelled this thread's step-over above. We still
|
|
need to unsuspend all other LWPs, and set them back
|
|
running again while the signal handler runs. */
|
|
unsuspend_all_lwps (event_child);
|
|
|
|
/* Enqueue the pending signal info so that proceed_all_lwps
|
|
doesn't lose it. */
|
|
enqueue_pending_signal (event_child, WSTOPSIG (w), info_p);
|
|
|
|
proceed_all_lwps ();
|
|
}
|
|
else
|
|
{
|
|
linux_resume_one_lwp (event_child, event_child->stepping,
|
|
WSTOPSIG (w), info_p);
|
|
}
|
|
|
|
if (debug_threads)
|
|
debug_exit ();
|
|
|
|
return ignore_event (ourstatus);
|
|
}
|
|
|
|
/* Note that all addresses are always "out of the step range" when
|
|
there's no range to begin with. */
|
|
in_step_range = lwp_in_step_range (event_child);
|
|
|
|
/* If GDB wanted this thread to single step, and the thread is out
|
|
of the step range, we always want to report the SIGTRAP, and let
|
|
GDB handle it. Watchpoints should always be reported. So should
|
|
signals we can't explain. A SIGTRAP we can't explain could be a
|
|
GDB breakpoint --- we may or not support Z0 breakpoints. If we
|
|
do, we're be able to handle GDB breakpoints on top of internal
|
|
breakpoints, by handling the internal breakpoint and still
|
|
reporting the event to GDB. If we don't, we're out of luck, GDB
|
|
won't see the breakpoint hit. If we see a single-step event but
|
|
the thread should be continuing, don't pass the trap to gdb.
|
|
That indicates that we had previously finished a single-step but
|
|
left the single-step pending -- see
|
|
complete_ongoing_step_over. */
|
|
report_to_gdb = (!maybe_internal_trap
|
|
|| (current_thread->last_resume_kind == resume_step
|
|
&& !in_step_range)
|
|
|| event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
|
|
|| (!in_step_range
|
|
&& !bp_explains_trap
|
|
&& !trace_event
|
|
&& !step_over_finished
|
|
&& !(current_thread->last_resume_kind == resume_continue
|
|
&& event_child->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP))
|
|
|| (gdb_breakpoint_here (event_child->stop_pc)
|
|
&& gdb_condition_true_at_breakpoint (event_child->stop_pc)
|
|
&& gdb_no_commands_at_breakpoint (event_child->stop_pc))
|
|
|| event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE);
|
|
|
|
run_breakpoint_commands (event_child->stop_pc);
|
|
|
|
/* We found no reason GDB would want us to stop. We either hit one
|
|
of our own breakpoints, or finished an internal step GDB
|
|
shouldn't know about. */
|
|
if (!report_to_gdb)
|
|
{
|
|
if (debug_threads)
|
|
{
|
|
if (bp_explains_trap)
|
|
debug_printf ("Hit a gdbserver breakpoint.\n");
|
|
if (step_over_finished)
|
|
debug_printf ("Step-over finished.\n");
|
|
if (trace_event)
|
|
debug_printf ("Tracepoint event.\n");
|
|
if (lwp_in_step_range (event_child))
|
|
debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
|
|
paddress (event_child->stop_pc),
|
|
paddress (event_child->step_range_start),
|
|
paddress (event_child->step_range_end));
|
|
}
|
|
|
|
/* We're not reporting this breakpoint to GDB, so apply the
|
|
decr_pc_after_break adjustment to the inferior's regcache
|
|
ourselves. */
|
|
|
|
if (the_low_target.set_pc != NULL)
|
|
{
|
|
struct regcache *regcache
|
|
= get_thread_regcache (current_thread, 1);
|
|
(*the_low_target.set_pc) (regcache, event_child->stop_pc);
|
|
}
|
|
|
|
if (step_over_finished)
|
|
{
|
|
/* If we have finished stepping over a breakpoint, we've
|
|
stopped and suspended all LWPs momentarily except the
|
|
stepping one. This is where we resume them all again.
|
|
We're going to keep waiting, so use proceed, which
|
|
handles stepping over the next breakpoint. */
|
|
unsuspend_all_lwps (event_child);
|
|
}
|
|
else
|
|
{
|
|
/* Remove the single-step breakpoints if any. Note that
|
|
there isn't single-step breakpoint if we finished stepping
|
|
over. */
|
|
if (can_software_single_step ()
|
|
&& has_single_step_breakpoints (current_thread))
|
|
{
|
|
stop_all_lwps (0, event_child);
|
|
delete_single_step_breakpoints (current_thread);
|
|
unstop_all_lwps (0, event_child);
|
|
}
|
|
}
|
|
|
|
if (debug_threads)
|
|
debug_printf ("proceeding all threads.\n");
|
|
proceed_all_lwps ();
|
|
|
|
if (debug_threads)
|
|
debug_exit ();
|
|
|
|
return ignore_event (ourstatus);
|
|
}
|
|
|
|
if (debug_threads)
|
|
{
|
|
if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE)
|
|
{
|
|
std::string str
|
|
= target_waitstatus_to_string (&event_child->waitstatus);
|
|
|
|
debug_printf ("LWP %ld: extended event with waitstatus %s\n",
|
|
lwpid_of (get_lwp_thread (event_child)), str.c_str ());
|
|
}
|
|
if (current_thread->last_resume_kind == resume_step)
|
|
{
|
|
if (event_child->step_range_start == event_child->step_range_end)
|
|
debug_printf ("GDB wanted to single-step, reporting event.\n");
|
|
else if (!lwp_in_step_range (event_child))
|
|
debug_printf ("Out of step range, reporting event.\n");
|
|
}
|
|
if (event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT)
|
|
debug_printf ("Stopped by watchpoint.\n");
|
|
else if (gdb_breakpoint_here (event_child->stop_pc))
|
|
debug_printf ("Stopped by GDB breakpoint.\n");
|
|
if (debug_threads)
|
|
debug_printf ("Hit a non-gdbserver trap event.\n");
|
|
}
|
|
|
|
/* Alright, we're going to report a stop. */
|
|
|
|
/* Remove single-step breakpoints. */
|
|
if (can_software_single_step ())
|
|
{
|
|
/* Remove single-step breakpoints or not. It it is true, stop all
|
|
lwps, so that other threads won't hit the breakpoint in the
|
|
staled memory. */
|
|
int remove_single_step_breakpoints_p = 0;
|
|
|
|
if (non_stop)
|
|
{
|
|
remove_single_step_breakpoints_p
|
|
= has_single_step_breakpoints (current_thread);
|
|
}
|
|
else
|
|
{
|
|
/* In all-stop, a stop reply cancels all previous resume
|
|
requests. Delete all single-step breakpoints. */
|
|
|
|
find_thread ([&] (thread_info *thread) {
|
|
if (has_single_step_breakpoints (thread))
|
|
{
|
|
remove_single_step_breakpoints_p = 1;
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
});
|
|
}
|
|
|
|
if (remove_single_step_breakpoints_p)
|
|
{
|
|
/* If we remove single-step breakpoints from memory, stop all lwps,
|
|
so that other threads won't hit the breakpoint in the staled
|
|
memory. */
|
|
stop_all_lwps (0, event_child);
|
|
|
|
if (non_stop)
|
|
{
|
|
gdb_assert (has_single_step_breakpoints (current_thread));
|
|
delete_single_step_breakpoints (current_thread);
|
|
}
|
|
else
|
|
{
|
|
for_each_thread ([] (thread_info *thread){
|
|
if (has_single_step_breakpoints (thread))
|
|
delete_single_step_breakpoints (thread);
|
|
});
|
|
}
|
|
|
|
unstop_all_lwps (0, event_child);
|
|
}
|
|
}
|
|
|
|
if (!stabilizing_threads)
|
|
{
|
|
/* In all-stop, stop all threads. */
|
|
if (!non_stop)
|
|
stop_all_lwps (0, NULL);
|
|
|
|
if (step_over_finished)
|
|
{
|
|
if (!non_stop)
|
|
{
|
|
/* If we were doing a step-over, all other threads but
|
|
the stepping one had been paused in start_step_over,
|
|
with their suspend counts incremented. We don't want
|
|
to do a full unstop/unpause, because we're in
|
|
all-stop mode (so we want threads stopped), but we
|
|
still need to unsuspend the other threads, to
|
|
decrement their `suspended' count back. */
|
|
unsuspend_all_lwps (event_child);
|
|
}
|
|
else
|
|
{
|
|
/* If we just finished a step-over, then all threads had
|
|
been momentarily paused. In all-stop, that's fine,
|
|
we want threads stopped by now anyway. In non-stop,
|
|
we need to re-resume threads that GDB wanted to be
|
|
running. */
|
|
unstop_all_lwps (1, event_child);
|
|
}
|
|
}
|
|
|
|
/* If we're not waiting for a specific LWP, choose an event LWP
|
|
from among those that have had events. Giving equal priority
|
|
to all LWPs that have had events helps prevent
|
|
starvation. */
|
|
if (ptid_equal (ptid, minus_one_ptid))
|
|
{
|
|
event_child->status_pending_p = 1;
|
|
event_child->status_pending = w;
|
|
|
|
select_event_lwp (&event_child);
|
|
|
|
/* current_thread and event_child must stay in sync. */
|
|
current_thread = get_lwp_thread (event_child);
|
|
|
|
event_child->status_pending_p = 0;
|
|
w = event_child->status_pending;
|
|
}
|
|
|
|
|
|
/* Stabilize threads (move out of jump pads). */
|
|
if (!non_stop)
|
|
stabilize_threads ();
|
|
}
|
|
else
|
|
{
|
|
/* If we just finished a step-over, then all threads had been
|
|
momentarily paused. In all-stop, that's fine, we want
|
|
threads stopped by now anyway. In non-stop, we need to
|
|
re-resume threads that GDB wanted to be running. */
|
|
if (step_over_finished)
|
|
unstop_all_lwps (1, event_child);
|
|
}
|
|
|
|
if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE)
|
|
{
|
|
/* If the reported event is an exit, fork, vfork or exec, let
|
|
GDB know. */
|
|
|
|
/* Break the unreported fork relationship chain. */
|
|
if (event_child->waitstatus.kind == TARGET_WAITKIND_FORKED
|
|
|| event_child->waitstatus.kind == TARGET_WAITKIND_VFORKED)
|
|
{
|
|
event_child->fork_relative->fork_relative = NULL;
|
|
event_child->fork_relative = NULL;
|
|
}
|
|
|
|
*ourstatus = event_child->waitstatus;
|
|
/* Clear the event lwp's waitstatus since we handled it already. */
|
|
event_child->waitstatus.kind = TARGET_WAITKIND_IGNORE;
|
|
}
|
|
else
|
|
ourstatus->kind = TARGET_WAITKIND_STOPPED;
|
|
|
|
/* Now that we've selected our final event LWP, un-adjust its PC if
|
|
it was a software breakpoint, and the client doesn't know we can
|
|
adjust the breakpoint ourselves. */
|
|
if (event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
|
|
&& !swbreak_feature)
|
|
{
|
|
int decr_pc = the_low_target.decr_pc_after_break;
|
|
|
|
if (decr_pc != 0)
|
|
{
|
|
struct regcache *regcache
|
|
= get_thread_regcache (current_thread, 1);
|
|
(*the_low_target.set_pc) (regcache, event_child->stop_pc + decr_pc);
|
|
}
|
|
}
|
|
|
|
if (WSTOPSIG (w) == SYSCALL_SIGTRAP)
|
|
{
|
|
get_syscall_trapinfo (event_child,
|
|
&ourstatus->value.syscall_number);
|
|
ourstatus->kind = event_child->syscall_state;
|
|
}
|
|
else if (current_thread->last_resume_kind == resume_stop
|
|
&& WSTOPSIG (w) == SIGSTOP)
|
|
{
|
|
/* A thread that has been requested to stop by GDB with vCont;t,
|
|
and it stopped cleanly, so report as SIG0. The use of
|
|
SIGSTOP is an implementation detail. */
|
|
ourstatus->value.sig = GDB_SIGNAL_0;
|
|
}
|
|
else if (current_thread->last_resume_kind == resume_stop
|
|
&& WSTOPSIG (w) != SIGSTOP)
|
|
{
|
|
/* A thread that has been requested to stop by GDB with vCont;t,
|
|
but, it stopped for other reasons. */
|
|
ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
|
|
}
|
|
else if (ourstatus->kind == TARGET_WAITKIND_STOPPED)
|
|
{
|
|
ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
|
|
}
|
|
|
|
gdb_assert (ptid_equal (step_over_bkpt, null_ptid));
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
|
|
target_pid_to_str (ptid_of (current_thread)),
|
|
ourstatus->kind, ourstatus->value.sig);
|
|
debug_exit ();
|
|
}
|
|
|
|
if (ourstatus->kind == TARGET_WAITKIND_EXITED)
|
|
return filter_exit_event (event_child, ourstatus);
|
|
|
|
return ptid_of (current_thread);
|
|
}
|
|
|
|
/* Get rid of any pending event in the pipe. */
|
|
static void
|
|
async_file_flush (void)
|
|
{
|
|
int ret;
|
|
char buf;
|
|
|
|
do
|
|
ret = read (linux_event_pipe[0], &buf, 1);
|
|
while (ret >= 0 || (ret == -1 && errno == EINTR));
|
|
}
|
|
|
|
/* Put something in the pipe, so the event loop wakes up. */
|
|
static void
|
|
async_file_mark (void)
|
|
{
|
|
int ret;
|
|
|
|
async_file_flush ();
|
|
|
|
do
|
|
ret = write (linux_event_pipe[1], "+", 1);
|
|
while (ret == 0 || (ret == -1 && errno == EINTR));
|
|
|
|
/* Ignore EAGAIN. If the pipe is full, the event loop will already
|
|
be awakened anyway. */
|
|
}
|
|
|
|
static ptid_t
|
|
linux_wait (ptid_t ptid,
|
|
struct target_waitstatus *ourstatus, int target_options)
|
|
{
|
|
ptid_t event_ptid;
|
|
|
|
/* Flush the async file first. */
|
|
if (target_is_async_p ())
|
|
async_file_flush ();
|
|
|
|
do
|
|
{
|
|
event_ptid = linux_wait_1 (ptid, ourstatus, target_options);
|
|
}
|
|
while ((target_options & TARGET_WNOHANG) == 0
|
|
&& ptid_equal (event_ptid, null_ptid)
|
|
&& ourstatus->kind == TARGET_WAITKIND_IGNORE);
|
|
|
|
/* If at least one stop was reported, there may be more. A single
|
|
SIGCHLD can signal more than one child stop. */
|
|
if (target_is_async_p ()
|
|
&& (target_options & TARGET_WNOHANG) != 0
|
|
&& !ptid_equal (event_ptid, null_ptid))
|
|
async_file_mark ();
|
|
|
|
return event_ptid;
|
|
}
|
|
|
|
/* Send a signal to an LWP. */
|
|
|
|
static int
|
|
kill_lwp (unsigned long lwpid, int signo)
|
|
{
|
|
int ret;
|
|
|
|
errno = 0;
|
|
ret = syscall (__NR_tkill, lwpid, signo);
|
|
if (errno == ENOSYS)
|
|
{
|
|
/* If tkill fails, then we are not using nptl threads, a
|
|
configuration we no longer support. */
|
|
perror_with_name (("tkill"));
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
void
|
|
linux_stop_lwp (struct lwp_info *lwp)
|
|
{
|
|
send_sigstop (lwp);
|
|
}
|
|
|
|
static void
|
|
send_sigstop (struct lwp_info *lwp)
|
|
{
|
|
int pid;
|
|
|
|
pid = lwpid_of (get_lwp_thread (lwp));
|
|
|
|
/* If we already have a pending stop signal for this process, don't
|
|
send another. */
|
|
if (lwp->stop_expected)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Have pending sigstop for lwp %d\n", pid);
|
|
|
|
return;
|
|
}
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Sending sigstop to lwp %d\n", pid);
|
|
|
|
lwp->stop_expected = 1;
|
|
kill_lwp (pid, SIGSTOP);
|
|
}
|
|
|
|
static void
|
|
send_sigstop (thread_info *thread, lwp_info *except)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (thread);
|
|
|
|
/* Ignore EXCEPT. */
|
|
if (lwp == except)
|
|
return;
|
|
|
|
if (lwp->stopped)
|
|
return;
|
|
|
|
send_sigstop (lwp);
|
|
}
|
|
|
|
/* Increment the suspend count of an LWP, and stop it, if not stopped
|
|
yet. */
|
|
static void
|
|
suspend_and_send_sigstop (thread_info *thread, lwp_info *except)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (thread);
|
|
|
|
/* Ignore EXCEPT. */
|
|
if (lwp == except)
|
|
return;
|
|
|
|
lwp_suspended_inc (lwp);
|
|
|
|
send_sigstop (thread, except);
|
|
}
|
|
|
|
static void
|
|
mark_lwp_dead (struct lwp_info *lwp, int wstat)
|
|
{
|
|
/* Store the exit status for later. */
|
|
lwp->status_pending_p = 1;
|
|
lwp->status_pending = wstat;
|
|
|
|
/* Store in waitstatus as well, as there's nothing else to process
|
|
for this event. */
|
|
if (WIFEXITED (wstat))
|
|
{
|
|
lwp->waitstatus.kind = TARGET_WAITKIND_EXITED;
|
|
lwp->waitstatus.value.integer = WEXITSTATUS (wstat);
|
|
}
|
|
else if (WIFSIGNALED (wstat))
|
|
{
|
|
lwp->waitstatus.kind = TARGET_WAITKIND_SIGNALLED;
|
|
lwp->waitstatus.value.sig = gdb_signal_from_host (WTERMSIG (wstat));
|
|
}
|
|
|
|
/* Prevent trying to stop it. */
|
|
lwp->stopped = 1;
|
|
|
|
/* No further stops are expected from a dead lwp. */
|
|
lwp->stop_expected = 0;
|
|
}
|
|
|
|
/* Return true if LWP has exited already, and has a pending exit event
|
|
to report to GDB. */
|
|
|
|
static int
|
|
lwp_is_marked_dead (struct lwp_info *lwp)
|
|
{
|
|
return (lwp->status_pending_p
|
|
&& (WIFEXITED (lwp->status_pending)
|
|
|| WIFSIGNALED (lwp->status_pending)));
|
|
}
|
|
|
|
/* Wait for all children to stop for the SIGSTOPs we just queued. */
|
|
|
|
static void
|
|
wait_for_sigstop (void)
|
|
{
|
|
struct thread_info *saved_thread;
|
|
ptid_t saved_tid;
|
|
int wstat;
|
|
int ret;
|
|
|
|
saved_thread = current_thread;
|
|
if (saved_thread != NULL)
|
|
saved_tid = saved_thread->id;
|
|
else
|
|
saved_tid = null_ptid; /* avoid bogus unused warning */
|
|
|
|
if (debug_threads)
|
|
debug_printf ("wait_for_sigstop: pulling events\n");
|
|
|
|
/* Passing NULL_PTID as filter indicates we want all events to be
|
|
left pending. Eventually this returns when there are no
|
|
unwaited-for children left. */
|
|
ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
|
|
&wstat, __WALL);
|
|
gdb_assert (ret == -1);
|
|
|
|
if (saved_thread == NULL || linux_thread_alive (saved_tid))
|
|
current_thread = saved_thread;
|
|
else
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Previously current thread died.\n");
|
|
|
|
/* We can't change the current inferior behind GDB's back,
|
|
otherwise, a subsequent command may apply to the wrong
|
|
process. */
|
|
current_thread = NULL;
|
|
}
|
|
}
|
|
|
|
/* Returns true if THREAD is stopped in a jump pad, and we can't
|
|
move it out, because we need to report the stop event to GDB. For
|
|
example, if the user puts a breakpoint in the jump pad, it's
|
|
because she wants to debug it. */
|
|
|
|
static bool
|
|
stuck_in_jump_pad_callback (thread_info *thread)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (thread);
|
|
|
|
if (lwp->suspended != 0)
|
|
{
|
|
internal_error (__FILE__, __LINE__,
|
|
"LWP %ld is suspended, suspended=%d\n",
|
|
lwpid_of (thread), lwp->suspended);
|
|
}
|
|
gdb_assert (lwp->stopped);
|
|
|
|
/* Allow debugging the jump pad, gdb_collect, etc.. */
|
|
return (supports_fast_tracepoints ()
|
|
&& agent_loaded_p ()
|
|
&& (gdb_breakpoint_here (lwp->stop_pc)
|
|
|| lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
|
|
|| thread->last_resume_kind == resume_step)
|
|
&& (linux_fast_tracepoint_collecting (lwp, NULL)
|
|
!= fast_tpoint_collect_result::not_collecting));
|
|
}
|
|
|
|
static void
|
|
move_out_of_jump_pad_callback (thread_info *thread)
|
|
{
|
|
struct thread_info *saved_thread;
|
|
struct lwp_info *lwp = get_thread_lwp (thread);
|
|
int *wstat;
|
|
|
|
if (lwp->suspended != 0)
|
|
{
|
|
internal_error (__FILE__, __LINE__,
|
|
"LWP %ld is suspended, suspended=%d\n",
|
|
lwpid_of (thread), lwp->suspended);
|
|
}
|
|
gdb_assert (lwp->stopped);
|
|
|
|
/* For gdb_breakpoint_here. */
|
|
saved_thread = current_thread;
|
|
current_thread = thread;
|
|
|
|
wstat = lwp->status_pending_p ? &lwp->status_pending : NULL;
|
|
|
|
/* Allow debugging the jump pad, gdb_collect, etc. */
|
|
if (!gdb_breakpoint_here (lwp->stop_pc)
|
|
&& lwp->stop_reason != TARGET_STOPPED_BY_WATCHPOINT
|
|
&& thread->last_resume_kind != resume_step
|
|
&& maybe_move_out_of_jump_pad (lwp, wstat))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
|
|
lwpid_of (thread));
|
|
|
|
if (wstat)
|
|
{
|
|
lwp->status_pending_p = 0;
|
|
enqueue_one_deferred_signal (lwp, wstat);
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Signal %d for LWP %ld deferred "
|
|
"(in jump pad)\n",
|
|
WSTOPSIG (*wstat), lwpid_of (thread));
|
|
}
|
|
|
|
linux_resume_one_lwp (lwp, 0, 0, NULL);
|
|
}
|
|
else
|
|
lwp_suspended_inc (lwp);
|
|
|
|
current_thread = saved_thread;
|
|
}
|
|
|
|
static bool
|
|
lwp_running (thread_info *thread)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (thread);
|
|
|
|
if (lwp_is_marked_dead (lwp))
|
|
return false;
|
|
|
|
return !lwp->stopped;
|
|
}
|
|
|
|
/* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
|
|
If SUSPEND, then also increase the suspend count of every LWP,
|
|
except EXCEPT. */
|
|
|
|
static void
|
|
stop_all_lwps (int suspend, struct lwp_info *except)
|
|
{
|
|
/* Should not be called recursively. */
|
|
gdb_assert (stopping_threads == NOT_STOPPING_THREADS);
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_enter ();
|
|
debug_printf ("stop_all_lwps (%s, except=%s)\n",
|
|
suspend ? "stop-and-suspend" : "stop",
|
|
except != NULL
|
|
? target_pid_to_str (ptid_of (get_lwp_thread (except)))
|
|
: "none");
|
|
}
|
|
|
|
stopping_threads = (suspend
|
|
? STOPPING_AND_SUSPENDING_THREADS
|
|
: STOPPING_THREADS);
|
|
|
|
if (suspend)
|
|
for_each_thread ([&] (thread_info *thread)
|
|
{
|
|
suspend_and_send_sigstop (thread, except);
|
|
});
|
|
else
|
|
for_each_thread ([&] (thread_info *thread)
|
|
{
|
|
send_sigstop (thread, except);
|
|
});
|
|
|
|
wait_for_sigstop ();
|
|
stopping_threads = NOT_STOPPING_THREADS;
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("stop_all_lwps done, setting stopping_threads "
|
|
"back to !stopping\n");
|
|
debug_exit ();
|
|
}
|
|
}
|
|
|
|
/* Enqueue one signal in the chain of signals which need to be
|
|
delivered to this process on next resume. */
|
|
|
|
static void
|
|
enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info)
|
|
{
|
|
struct pending_signals *p_sig = XNEW (struct pending_signals);
|
|
|
|
p_sig->prev = lwp->pending_signals;
|
|
p_sig->signal = signal;
|
|
if (info == NULL)
|
|
memset (&p_sig->info, 0, sizeof (siginfo_t));
|
|
else
|
|
memcpy (&p_sig->info, info, sizeof (siginfo_t));
|
|
lwp->pending_signals = p_sig;
|
|
}
|
|
|
|
/* Install breakpoints for software single stepping. */
|
|
|
|
static void
|
|
install_software_single_step_breakpoints (struct lwp_info *lwp)
|
|
{
|
|
struct thread_info *thread = get_lwp_thread (lwp);
|
|
struct regcache *regcache = get_thread_regcache (thread, 1);
|
|
struct cleanup *old_chain = make_cleanup_restore_current_thread ();
|
|
|
|
current_thread = thread;
|
|
std::vector<CORE_ADDR> next_pcs = the_low_target.get_next_pcs (regcache);
|
|
|
|
for (CORE_ADDR pc : next_pcs)
|
|
set_single_step_breakpoint (pc, current_ptid);
|
|
|
|
do_cleanups (old_chain);
|
|
}
|
|
|
|
/* Single step via hardware or software single step.
|
|
Return 1 if hardware single stepping, 0 if software single stepping
|
|
or can't single step. */
|
|
|
|
static int
|
|
single_step (struct lwp_info* lwp)
|
|
{
|
|
int step = 0;
|
|
|
|
if (can_hardware_single_step ())
|
|
{
|
|
step = 1;
|
|
}
|
|
else if (can_software_single_step ())
|
|
{
|
|
install_software_single_step_breakpoints (lwp);
|
|
step = 0;
|
|
}
|
|
else
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("stepping is not implemented on this target");
|
|
}
|
|
|
|
return step;
|
|
}
|
|
|
|
/* The signal can be delivered to the inferior if we are not trying to
|
|
finish a fast tracepoint collect. Since signal can be delivered in
|
|
the step-over, the program may go to signal handler and trap again
|
|
after return from the signal handler. We can live with the spurious
|
|
double traps. */
|
|
|
|
static int
|
|
lwp_signal_can_be_delivered (struct lwp_info *lwp)
|
|
{
|
|
return (lwp->collecting_fast_tracepoint
|
|
== fast_tpoint_collect_result::not_collecting);
|
|
}
|
|
|
|
/* Resume execution of LWP. If STEP is nonzero, single-step it. If
|
|
SIGNAL is nonzero, give it that signal. */
|
|
|
|
static void
|
|
linux_resume_one_lwp_throw (struct lwp_info *lwp,
|
|
int step, int signal, siginfo_t *info)
|
|
{
|
|
struct thread_info *thread = get_lwp_thread (lwp);
|
|
struct thread_info *saved_thread;
|
|
int ptrace_request;
|
|
struct process_info *proc = get_thread_process (thread);
|
|
|
|
/* Note that target description may not be initialised
|
|
(proc->tdesc == NULL) at this point because the program hasn't
|
|
stopped at the first instruction yet. It means GDBserver skips
|
|
the extra traps from the wrapper program (see option --wrapper).
|
|
Code in this function that requires register access should be
|
|
guarded by proc->tdesc == NULL or something else. */
|
|
|
|
if (lwp->stopped == 0)
|
|
return;
|
|
|
|
gdb_assert (lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE);
|
|
|
|
fast_tpoint_collect_result fast_tp_collecting
|
|
= lwp->collecting_fast_tracepoint;
|
|
|
|
gdb_assert (!stabilizing_threads
|
|
|| (fast_tp_collecting
|
|
!= fast_tpoint_collect_result::not_collecting));
|
|
|
|
/* Cancel actions that rely on GDB not changing the PC (e.g., the
|
|
user used the "jump" command, or "set $pc = foo"). */
|
|
if (thread->while_stepping != NULL && lwp->stop_pc != get_pc (lwp))
|
|
{
|
|
/* Collecting 'while-stepping' actions doesn't make sense
|
|
anymore. */
|
|
release_while_stepping_state_list (thread);
|
|
}
|
|
|
|
/* If we have pending signals or status, and a new signal, enqueue the
|
|
signal. Also enqueue the signal if it can't be delivered to the
|
|
inferior right now. */
|
|
if (signal != 0
|
|
&& (lwp->status_pending_p
|
|
|| lwp->pending_signals != NULL
|
|
|| !lwp_signal_can_be_delivered (lwp)))
|
|
{
|
|
enqueue_pending_signal (lwp, signal, info);
|
|
|
|
/* Postpone any pending signal. It was enqueued above. */
|
|
signal = 0;
|
|
}
|
|
|
|
if (lwp->status_pending_p)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Not resuming lwp %ld (%s, stop %s);"
|
|
" has pending status\n",
|
|
lwpid_of (thread), step ? "step" : "continue",
|
|
lwp->stop_expected ? "expected" : "not expected");
|
|
return;
|
|
}
|
|
|
|
saved_thread = current_thread;
|
|
current_thread = thread;
|
|
|
|
/* This bit needs some thinking about. If we get a signal that
|
|
we must report while a single-step reinsert is still pending,
|
|
we often end up resuming the thread. It might be better to
|
|
(ew) allow a stack of pending events; then we could be sure that
|
|
the reinsert happened right away and not lose any signals.
|
|
|
|
Making this stack would also shrink the window in which breakpoints are
|
|
uninserted (see comment in linux_wait_for_lwp) but not enough for
|
|
complete correctness, so it won't solve that problem. It may be
|
|
worthwhile just to solve this one, however. */
|
|
if (lwp->bp_reinsert != 0)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf (" pending reinsert at 0x%s\n",
|
|
paddress (lwp->bp_reinsert));
|
|
|
|
if (can_hardware_single_step ())
|
|
{
|
|
if (fast_tp_collecting == fast_tpoint_collect_result::not_collecting)
|
|
{
|
|
if (step == 0)
|
|
warning ("BAD - reinserting but not stepping.");
|
|
if (lwp->suspended)
|
|
warning ("BAD - reinserting and suspended(%d).",
|
|
lwp->suspended);
|
|
}
|
|
}
|
|
|
|
step = maybe_hw_step (thread);
|
|
}
|
|
|
|
if (fast_tp_collecting == fast_tpoint_collect_result::before_insn)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
|
|
" (exit-jump-pad-bkpt)\n",
|
|
lwpid_of (thread));
|
|
}
|
|
else if (fast_tp_collecting == fast_tpoint_collect_result::at_insn)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
|
|
" single-stepping\n",
|
|
lwpid_of (thread));
|
|
|
|
if (can_hardware_single_step ())
|
|
step = 1;
|
|
else
|
|
{
|
|
internal_error (__FILE__, __LINE__,
|
|
"moving out of jump pad single-stepping"
|
|
" not implemented on this target");
|
|
}
|
|
}
|
|
|
|
/* If we have while-stepping actions in this thread set it stepping.
|
|
If we have a signal to deliver, it may or may not be set to
|
|
SIG_IGN, we don't know. Assume so, and allow collecting
|
|
while-stepping into a signal handler. A possible smart thing to
|
|
do would be to set an internal breakpoint at the signal return
|
|
address, continue, and carry on catching this while-stepping
|
|
action only when that breakpoint is hit. A future
|
|
enhancement. */
|
|
if (thread->while_stepping != NULL)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
|
|
lwpid_of (thread));
|
|
|
|
step = single_step (lwp);
|
|
}
|
|
|
|
if (proc->tdesc != NULL && the_low_target.get_pc != NULL)
|
|
{
|
|
struct regcache *regcache = get_thread_regcache (current_thread, 1);
|
|
|
|
lwp->stop_pc = (*the_low_target.get_pc) (regcache);
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_printf (" %s from pc 0x%lx\n", step ? "step" : "continue",
|
|
(long) lwp->stop_pc);
|
|
}
|
|
}
|
|
|
|
/* If we have pending signals, consume one if it can be delivered to
|
|
the inferior. */
|
|
if (lwp->pending_signals != NULL && lwp_signal_can_be_delivered (lwp))
|
|
{
|
|
struct pending_signals **p_sig;
|
|
|
|
p_sig = &lwp->pending_signals;
|
|
while ((*p_sig)->prev != NULL)
|
|
p_sig = &(*p_sig)->prev;
|
|
|
|
signal = (*p_sig)->signal;
|
|
if ((*p_sig)->info.si_signo != 0)
|
|
ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
|
|
&(*p_sig)->info);
|
|
|
|
free (*p_sig);
|
|
*p_sig = NULL;
|
|
}
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
|
|
lwpid_of (thread), step ? "step" : "continue", signal,
|
|
lwp->stop_expected ? "expected" : "not expected");
|
|
|
|
if (the_low_target.prepare_to_resume != NULL)
|
|
the_low_target.prepare_to_resume (lwp);
|
|
|
|
regcache_invalidate_thread (thread);
|
|
errno = 0;
|
|
lwp->stepping = step;
|
|
if (step)
|
|
ptrace_request = PTRACE_SINGLESTEP;
|
|
else if (gdb_catching_syscalls_p (lwp))
|
|
ptrace_request = PTRACE_SYSCALL;
|
|
else
|
|
ptrace_request = PTRACE_CONT;
|
|
ptrace (ptrace_request,
|
|
lwpid_of (thread),
|
|
(PTRACE_TYPE_ARG3) 0,
|
|
/* Coerce to a uintptr_t first to avoid potential gcc warning
|
|
of coercing an 8 byte integer to a 4 byte pointer. */
|
|
(PTRACE_TYPE_ARG4) (uintptr_t) signal);
|
|
|
|
current_thread = saved_thread;
|
|
if (errno)
|
|
perror_with_name ("resuming thread");
|
|
|
|
/* Successfully resumed. Clear state that no longer makes sense,
|
|
and mark the LWP as running. Must not do this before resuming
|
|
otherwise if that fails other code will be confused. E.g., we'd
|
|
later try to stop the LWP and hang forever waiting for a stop
|
|
status. Note that we must not throw after this is cleared,
|
|
otherwise handle_zombie_lwp_error would get confused. */
|
|
lwp->stopped = 0;
|
|
lwp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
|
|
}
|
|
|
|
/* Called when we try to resume a stopped LWP and that errors out. If
|
|
the LWP is no longer in ptrace-stopped state (meaning it's zombie,
|
|
or about to become), discard the error, clear any pending status
|
|
the LWP may have, and return true (we'll collect the exit status
|
|
soon enough). Otherwise, return false. */
|
|
|
|
static int
|
|
check_ptrace_stopped_lwp_gone (struct lwp_info *lp)
|
|
{
|
|
struct thread_info *thread = get_lwp_thread (lp);
|
|
|
|
/* If we get an error after resuming the LWP successfully, we'd
|
|
confuse !T state for the LWP being gone. */
|
|
gdb_assert (lp->stopped);
|
|
|
|
/* We can't just check whether the LWP is in 'Z (Zombie)' state,
|
|
because even if ptrace failed with ESRCH, the tracee may be "not
|
|
yet fully dead", but already refusing ptrace requests. In that
|
|
case the tracee has 'R (Running)' state for a little bit
|
|
(observed in Linux 3.18). See also the note on ESRCH in the
|
|
ptrace(2) man page. Instead, check whether the LWP has any state
|
|
other than ptrace-stopped. */
|
|
|
|
/* Don't assume anything if /proc/PID/status can't be read. */
|
|
if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread)) == 0)
|
|
{
|
|
lp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
|
|
lp->status_pending_p = 0;
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
|
|
disappears while we try to resume it. */
|
|
|
|
static void
|
|
linux_resume_one_lwp (struct lwp_info *lwp,
|
|
int step, int signal, siginfo_t *info)
|
|
{
|
|
TRY
|
|
{
|
|
linux_resume_one_lwp_throw (lwp, step, signal, info);
|
|
}
|
|
CATCH (ex, RETURN_MASK_ERROR)
|
|
{
|
|
if (!check_ptrace_stopped_lwp_gone (lwp))
|
|
throw_exception (ex);
|
|
}
|
|
END_CATCH
|
|
}
|
|
|
|
/* This function is called once per thread via for_each_thread.
|
|
We look up which resume request applies to THREAD and mark it with a
|
|
pointer to the appropriate resume request.
|
|
|
|
This algorithm is O(threads * resume elements), but resume elements
|
|
is small (and will remain small at least until GDB supports thread
|
|
suspension). */
|
|
|
|
static void
|
|
linux_set_resume_request (thread_info *thread, thread_resume *resume, size_t n)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (thread);
|
|
|
|
for (int ndx = 0; ndx < n; ndx++)
|
|
{
|
|
ptid_t ptid = resume[ndx].thread;
|
|
if (ptid_equal (ptid, minus_one_ptid)
|
|
|| ptid == thread->id
|
|
/* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
|
|
of PID'. */
|
|
|| (ptid_get_pid (ptid) == pid_of (thread)
|
|
&& (ptid_is_pid (ptid)
|
|
|| ptid_get_lwp (ptid) == -1)))
|
|
{
|
|
if (resume[ndx].kind == resume_stop
|
|
&& thread->last_resume_kind == resume_stop)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("already %s LWP %ld at GDB's request\n",
|
|
(thread->last_status.kind
|
|
== TARGET_WAITKIND_STOPPED)
|
|
? "stopped"
|
|
: "stopping",
|
|
lwpid_of (thread));
|
|
|
|
continue;
|
|
}
|
|
|
|
/* Ignore (wildcard) resume requests for already-resumed
|
|
threads. */
|
|
if (resume[ndx].kind != resume_stop
|
|
&& thread->last_resume_kind != resume_stop)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("already %s LWP %ld at GDB's request\n",
|
|
(thread->last_resume_kind
|
|
== resume_step)
|
|
? "stepping"
|
|
: "continuing",
|
|
lwpid_of (thread));
|
|
continue;
|
|
}
|
|
|
|
/* Don't let wildcard resumes resume fork children that GDB
|
|
does not yet know are new fork children. */
|
|
if (lwp->fork_relative != NULL)
|
|
{
|
|
struct lwp_info *rel = lwp->fork_relative;
|
|
|
|
if (rel->status_pending_p
|
|
&& (rel->waitstatus.kind == TARGET_WAITKIND_FORKED
|
|
|| rel->waitstatus.kind == TARGET_WAITKIND_VFORKED))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("not resuming LWP %ld: has queued stop reply\n",
|
|
lwpid_of (thread));
|
|
continue;
|
|
}
|
|
}
|
|
|
|
/* If the thread has a pending event that has already been
|
|
reported to GDBserver core, but GDB has not pulled the
|
|
event out of the vStopped queue yet, likewise, ignore the
|
|
(wildcard) resume request. */
|
|
if (in_queued_stop_replies (thread->id))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("not resuming LWP %ld: has queued stop reply\n",
|
|
lwpid_of (thread));
|
|
continue;
|
|
}
|
|
|
|
lwp->resume = &resume[ndx];
|
|
thread->last_resume_kind = lwp->resume->kind;
|
|
|
|
lwp->step_range_start = lwp->resume->step_range_start;
|
|
lwp->step_range_end = lwp->resume->step_range_end;
|
|
|
|
/* If we had a deferred signal to report, dequeue one now.
|
|
This can happen if LWP gets more than one signal while
|
|
trying to get out of a jump pad. */
|
|
if (lwp->stopped
|
|
&& !lwp->status_pending_p
|
|
&& dequeue_one_deferred_signal (lwp, &lwp->status_pending))
|
|
{
|
|
lwp->status_pending_p = 1;
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
|
|
"leaving status pending.\n",
|
|
WSTOPSIG (lwp->status_pending),
|
|
lwpid_of (thread));
|
|
}
|
|
|
|
return;
|
|
}
|
|
}
|
|
|
|
/* No resume action for this thread. */
|
|
lwp->resume = NULL;
|
|
}
|
|
|
|
/* find_thread callback for linux_resume. Return true if this lwp has an
|
|
interesting status pending. */
|
|
|
|
static bool
|
|
resume_status_pending_p (thread_info *thread)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (thread);
|
|
|
|
/* LWPs which will not be resumed are not interesting, because
|
|
we might not wait for them next time through linux_wait. */
|
|
if (lwp->resume == NULL)
|
|
return false;
|
|
|
|
return thread_still_has_status_pending_p (thread);
|
|
}
|
|
|
|
/* Return 1 if this lwp that GDB wants running is stopped at an
|
|
internal breakpoint that we need to step over. It assumes that any
|
|
required STOP_PC adjustment has already been propagated to the
|
|
inferior's regcache. */
|
|
|
|
static bool
|
|
need_step_over_p (thread_info *thread)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (thread);
|
|
struct thread_info *saved_thread;
|
|
CORE_ADDR pc;
|
|
struct process_info *proc = get_thread_process (thread);
|
|
|
|
/* GDBserver is skipping the extra traps from the wrapper program,
|
|
don't have to do step over. */
|
|
if (proc->tdesc == NULL)
|
|
return false;
|
|
|
|
/* LWPs which will not be resumed are not interesting, because we
|
|
might not wait for them next time through linux_wait. */
|
|
|
|
if (!lwp->stopped)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
|
|
lwpid_of (thread));
|
|
return false;
|
|
}
|
|
|
|
if (thread->last_resume_kind == resume_stop)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
|
|
" stopped\n",
|
|
lwpid_of (thread));
|
|
return false;
|
|
}
|
|
|
|
gdb_assert (lwp->suspended >= 0);
|
|
|
|
if (lwp->suspended)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
|
|
lwpid_of (thread));
|
|
return false;
|
|
}
|
|
|
|
if (lwp->status_pending_p)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
|
|
" status.\n",
|
|
lwpid_of (thread));
|
|
return false;
|
|
}
|
|
|
|
/* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
|
|
or we have. */
|
|
pc = get_pc (lwp);
|
|
|
|
/* If the PC has changed since we stopped, then don't do anything,
|
|
and let the breakpoint/tracepoint be hit. This happens if, for
|
|
instance, GDB handled the decr_pc_after_break subtraction itself,
|
|
GDB is OOL stepping this thread, or the user has issued a "jump"
|
|
command, or poked thread's registers herself. */
|
|
if (pc != lwp->stop_pc)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
|
|
"Old stop_pc was 0x%s, PC is now 0x%s\n",
|
|
lwpid_of (thread),
|
|
paddress (lwp->stop_pc), paddress (pc));
|
|
return false;
|
|
}
|
|
|
|
/* On software single step target, resume the inferior with signal
|
|
rather than stepping over. */
|
|
if (can_software_single_step ()
|
|
&& lwp->pending_signals != NULL
|
|
&& lwp_signal_can_be_delivered (lwp))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
|
|
" signals.\n",
|
|
lwpid_of (thread));
|
|
|
|
return false;
|
|
}
|
|
|
|
saved_thread = current_thread;
|
|
current_thread = thread;
|
|
|
|
/* We can only step over breakpoints we know about. */
|
|
if (breakpoint_here (pc) || fast_tracepoint_jump_here (pc))
|
|
{
|
|
/* Don't step over a breakpoint that GDB expects to hit
|
|
though. If the condition is being evaluated on the target's side
|
|
and it evaluate to false, step over this breakpoint as well. */
|
|
if (gdb_breakpoint_here (pc)
|
|
&& gdb_condition_true_at_breakpoint (pc)
|
|
&& gdb_no_commands_at_breakpoint (pc))
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Need step over [LWP %ld]? yes, but found"
|
|
" GDB breakpoint at 0x%s; skipping step over\n",
|
|
lwpid_of (thread), paddress (pc));
|
|
|
|
current_thread = saved_thread;
|
|
return false;
|
|
}
|
|
else
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("Need step over [LWP %ld]? yes, "
|
|
"found breakpoint at 0x%s\n",
|
|
lwpid_of (thread), paddress (pc));
|
|
|
|
/* We've found an lwp that needs stepping over --- return 1 so
|
|
that find_thread stops looking. */
|
|
current_thread = saved_thread;
|
|
|
|
return true;
|
|
}
|
|
}
|
|
|
|
current_thread = saved_thread;
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
|
|
" at 0x%s\n",
|
|
lwpid_of (thread), paddress (pc));
|
|
|
|
return false;
|
|
}
|
|
|
|
/* Start a step-over operation on LWP. When LWP stopped at a
|
|
breakpoint, to make progress, we need to remove the breakpoint out
|
|
of the way. If we let other threads run while we do that, they may
|
|
pass by the breakpoint location and miss hitting it. To avoid
|
|
that, a step-over momentarily stops all threads while LWP is
|
|
single-stepped by either hardware or software while the breakpoint
|
|
is temporarily uninserted from the inferior. When the single-step
|
|
finishes, we reinsert the breakpoint, and let all threads that are
|
|
supposed to be running, run again. */
|
|
|
|
static int
|
|
start_step_over (struct lwp_info *lwp)
|
|
{
|
|
struct thread_info *thread = get_lwp_thread (lwp);
|
|
struct thread_info *saved_thread;
|
|
CORE_ADDR pc;
|
|
int step;
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
|
|
lwpid_of (thread));
|
|
|
|
stop_all_lwps (1, lwp);
|
|
|
|
if (lwp->suspended != 0)
|
|
{
|
|
internal_error (__FILE__, __LINE__,
|
|
"LWP %ld suspended=%d\n", lwpid_of (thread),
|
|
lwp->suspended);
|
|
}
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Done stopping all threads for step-over.\n");
|
|
|
|
/* Note, we should always reach here with an already adjusted PC,
|
|
either by GDB (if we're resuming due to GDB's request), or by our
|
|
caller, if we just finished handling an internal breakpoint GDB
|
|
shouldn't care about. */
|
|
pc = get_pc (lwp);
|
|
|
|
saved_thread = current_thread;
|
|
current_thread = thread;
|
|
|
|
lwp->bp_reinsert = pc;
|
|
uninsert_breakpoints_at (pc);
|
|
uninsert_fast_tracepoint_jumps_at (pc);
|
|
|
|
step = single_step (lwp);
|
|
|
|
current_thread = saved_thread;
|
|
|
|
linux_resume_one_lwp (lwp, step, 0, NULL);
|
|
|
|
/* Require next event from this LWP. */
|
|
step_over_bkpt = thread->id;
|
|
return 1;
|
|
}
|
|
|
|
/* Finish a step-over. Reinsert the breakpoint we had uninserted in
|
|
start_step_over, if still there, and delete any single-step
|
|
breakpoints we've set, on non hardware single-step targets. */
|
|
|
|
static int
|
|
finish_step_over (struct lwp_info *lwp)
|
|
{
|
|
if (lwp->bp_reinsert != 0)
|
|
{
|
|
struct thread_info *saved_thread = current_thread;
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Finished step over.\n");
|
|
|
|
current_thread = get_lwp_thread (lwp);
|
|
|
|
/* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
|
|
may be no breakpoint to reinsert there by now. */
|
|
reinsert_breakpoints_at (lwp->bp_reinsert);
|
|
reinsert_fast_tracepoint_jumps_at (lwp->bp_reinsert);
|
|
|
|
lwp->bp_reinsert = 0;
|
|
|
|
/* Delete any single-step breakpoints. No longer needed. We
|
|
don't have to worry about other threads hitting this trap,
|
|
and later not being able to explain it, because we were
|
|
stepping over a breakpoint, and we hold all threads but
|
|
LWP stopped while doing that. */
|
|
if (!can_hardware_single_step ())
|
|
{
|
|
gdb_assert (has_single_step_breakpoints (current_thread));
|
|
delete_single_step_breakpoints (current_thread);
|
|
}
|
|
|
|
step_over_bkpt = null_ptid;
|
|
current_thread = saved_thread;
|
|
return 1;
|
|
}
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
/* If there's a step over in progress, wait until all threads stop
|
|
(that is, until the stepping thread finishes its step), and
|
|
unsuspend all lwps. The stepping thread ends with its status
|
|
pending, which is processed later when we get back to processing
|
|
events. */
|
|
|
|
static void
|
|
complete_ongoing_step_over (void)
|
|
{
|
|
if (!ptid_equal (step_over_bkpt, null_ptid))
|
|
{
|
|
struct lwp_info *lwp;
|
|
int wstat;
|
|
int ret;
|
|
|
|
if (debug_threads)
|
|
debug_printf ("detach: step over in progress, finish it first\n");
|
|
|
|
/* Passing NULL_PTID as filter indicates we want all events to
|
|
be left pending. Eventually this returns when there are no
|
|
unwaited-for children left. */
|
|
ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
|
|
&wstat, __WALL);
|
|
gdb_assert (ret == -1);
|
|
|
|
lwp = find_lwp_pid (step_over_bkpt);
|
|
if (lwp != NULL)
|
|
finish_step_over (lwp);
|
|
step_over_bkpt = null_ptid;
|
|
unsuspend_all_lwps (lwp);
|
|
}
|
|
}
|
|
|
|
/* This function is called once per thread. We check the thread's resume
|
|
request, which will tell us whether to resume, step, or leave the thread
|
|
stopped; and what signal, if any, it should be sent.
|
|
|
|
For threads which we aren't explicitly told otherwise, we preserve
|
|
the stepping flag; this is used for stepping over gdbserver-placed
|
|
breakpoints.
|
|
|
|
If pending_flags was set in any thread, we queue any needed
|
|
signals, since we won't actually resume. We already have a pending
|
|
event to report, so we don't need to preserve any step requests;
|
|
they should be re-issued if necessary. */
|
|
|
|
static void
|
|
linux_resume_one_thread (thread_info *thread, bool leave_all_stopped)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (thread);
|
|
int leave_pending;
|
|
|
|
if (lwp->resume == NULL)
|
|
return;
|
|
|
|
if (lwp->resume->kind == resume_stop)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread));
|
|
|
|
if (!lwp->stopped)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("stopping LWP %ld\n", lwpid_of (thread));
|
|
|
|
/* Stop the thread, and wait for the event asynchronously,
|
|
through the event loop. */
|
|
send_sigstop (lwp);
|
|
}
|
|
else
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("already stopped LWP %ld\n",
|
|
lwpid_of (thread));
|
|
|
|
/* The LWP may have been stopped in an internal event that
|
|
was not meant to be notified back to GDB (e.g., gdbserver
|
|
breakpoint), so we should be reporting a stop event in
|
|
this case too. */
|
|
|
|
/* If the thread already has a pending SIGSTOP, this is a
|
|
no-op. Otherwise, something later will presumably resume
|
|
the thread and this will cause it to cancel any pending
|
|
operation, due to last_resume_kind == resume_stop. If
|
|
the thread already has a pending status to report, we
|
|
will still report it the next time we wait - see
|
|
status_pending_p_callback. */
|
|
|
|
/* If we already have a pending signal to report, then
|
|
there's no need to queue a SIGSTOP, as this means we're
|
|
midway through moving the LWP out of the jumppad, and we
|
|
will report the pending signal as soon as that is
|
|
finished. */
|
|
if (lwp->pending_signals_to_report == NULL)
|
|
send_sigstop (lwp);
|
|
}
|
|
|
|
/* For stop requests, we're done. */
|
|
lwp->resume = NULL;
|
|
thread->last_status.kind = TARGET_WAITKIND_IGNORE;
|
|
return;
|
|
}
|
|
|
|
/* If this thread which is about to be resumed has a pending status,
|
|
then don't resume it - we can just report the pending status.
|
|
Likewise if it is suspended, because e.g., another thread is
|
|
stepping past a breakpoint. Make sure to queue any signals that
|
|
would otherwise be sent. In all-stop mode, we do this decision
|
|
based on if *any* thread has a pending status. If there's a
|
|
thread that needs the step-over-breakpoint dance, then don't
|
|
resume any other thread but that particular one. */
|
|
leave_pending = (lwp->suspended
|
|
|| lwp->status_pending_p
|
|
|| leave_all_stopped);
|
|
|
|
/* If we have a new signal, enqueue the signal. */
|
|
if (lwp->resume->sig != 0)
|
|
{
|
|
siginfo_t info, *info_p;
|
|
|
|
/* If this is the same signal we were previously stopped by,
|
|
make sure to queue its siginfo. */
|
|
if (WIFSTOPPED (lwp->last_status)
|
|
&& WSTOPSIG (lwp->last_status) == lwp->resume->sig
|
|
&& ptrace (PTRACE_GETSIGINFO, lwpid_of (thread),
|
|
(PTRACE_TYPE_ARG3) 0, &info) == 0)
|
|
info_p = &info;
|
|
else
|
|
info_p = NULL;
|
|
|
|
enqueue_pending_signal (lwp, lwp->resume->sig, info_p);
|
|
}
|
|
|
|
if (!leave_pending)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("resuming LWP %ld\n", lwpid_of (thread));
|
|
|
|
proceed_one_lwp (thread, NULL);
|
|
}
|
|
else
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread));
|
|
}
|
|
|
|
thread->last_status.kind = TARGET_WAITKIND_IGNORE;
|
|
lwp->resume = NULL;
|
|
}
|
|
|
|
static void
|
|
linux_resume (struct thread_resume *resume_info, size_t n)
|
|
{
|
|
struct thread_info *need_step_over = NULL;
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_enter ();
|
|
debug_printf ("linux_resume:\n");
|
|
}
|
|
|
|
for_each_thread ([&] (thread_info *thread)
|
|
{
|
|
linux_set_resume_request (thread, resume_info, n);
|
|
});
|
|
|
|
/* If there is a thread which would otherwise be resumed, which has
|
|
a pending status, then don't resume any threads - we can just
|
|
report the pending status. Make sure to queue any signals that
|
|
would otherwise be sent. In non-stop mode, we'll apply this
|
|
logic to each thread individually. We consume all pending events
|
|
before considering to start a step-over (in all-stop). */
|
|
bool any_pending = false;
|
|
if (!non_stop)
|
|
any_pending = find_thread (resume_status_pending_p) != NULL;
|
|
|
|
/* If there is a thread which would otherwise be resumed, which is
|
|
stopped at a breakpoint that needs stepping over, then don't
|
|
resume any threads - have it step over the breakpoint with all
|
|
other threads stopped, then resume all threads again. Make sure
|
|
to queue any signals that would otherwise be delivered or
|
|
queued. */
|
|
if (!any_pending && supports_breakpoints ())
|
|
need_step_over = find_thread (need_step_over_p);
|
|
|
|
bool leave_all_stopped = (need_step_over != NULL || any_pending);
|
|
|
|
if (debug_threads)
|
|
{
|
|
if (need_step_over != NULL)
|
|
debug_printf ("Not resuming all, need step over\n");
|
|
else if (any_pending)
|
|
debug_printf ("Not resuming, all-stop and found "
|
|
"an LWP with pending status\n");
|
|
else
|
|
debug_printf ("Resuming, no pending status or step over needed\n");
|
|
}
|
|
|
|
/* Even if we're leaving threads stopped, queue all signals we'd
|
|
otherwise deliver. */
|
|
for_each_thread ([&] (thread_info *thread)
|
|
{
|
|
linux_resume_one_thread (thread, leave_all_stopped);
|
|
});
|
|
|
|
if (need_step_over)
|
|
start_step_over (get_thread_lwp (need_step_over));
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("linux_resume done\n");
|
|
debug_exit ();
|
|
}
|
|
|
|
/* We may have events that were pending that can/should be sent to
|
|
the client now. Trigger a linux_wait call. */
|
|
if (target_is_async_p ())
|
|
async_file_mark ();
|
|
}
|
|
|
|
/* This function is called once per thread. We check the thread's
|
|
last resume request, which will tell us whether to resume, step, or
|
|
leave the thread stopped. Any signal the client requested to be
|
|
delivered has already been enqueued at this point.
|
|
|
|
If any thread that GDB wants running is stopped at an internal
|
|
breakpoint that needs stepping over, we start a step-over operation
|
|
on that particular thread, and leave all others stopped. */
|
|
|
|
static void
|
|
proceed_one_lwp (thread_info *thread, lwp_info *except)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (thread);
|
|
int step;
|
|
|
|
if (lwp == except)
|
|
return;
|
|
|
|
if (debug_threads)
|
|
debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread));
|
|
|
|
if (!lwp->stopped)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf (" LWP %ld already running\n", lwpid_of (thread));
|
|
return;
|
|
}
|
|
|
|
if (thread->last_resume_kind == resume_stop
|
|
&& thread->last_status.kind != TARGET_WAITKIND_IGNORE)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf (" client wants LWP to remain %ld stopped\n",
|
|
lwpid_of (thread));
|
|
return;
|
|
}
|
|
|
|
if (lwp->status_pending_p)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf (" LWP %ld has pending status, leaving stopped\n",
|
|
lwpid_of (thread));
|
|
return;
|
|
}
|
|
|
|
gdb_assert (lwp->suspended >= 0);
|
|
|
|
if (lwp->suspended)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf (" LWP %ld is suspended\n", lwpid_of (thread));
|
|
return;
|
|
}
|
|
|
|
if (thread->last_resume_kind == resume_stop
|
|
&& lwp->pending_signals_to_report == NULL
|
|
&& (lwp->collecting_fast_tracepoint
|
|
== fast_tpoint_collect_result::not_collecting))
|
|
{
|
|
/* We haven't reported this LWP as stopped yet (otherwise, the
|
|
last_status.kind check above would catch it, and we wouldn't
|
|
reach here. This LWP may have been momentarily paused by a
|
|
stop_all_lwps call while handling for example, another LWP's
|
|
step-over. In that case, the pending expected SIGSTOP signal
|
|
that was queued at vCont;t handling time will have already
|
|
been consumed by wait_for_sigstop, and so we need to requeue
|
|
another one here. Note that if the LWP already has a SIGSTOP
|
|
pending, this is a no-op. */
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Client wants LWP %ld to stop. "
|
|
"Making sure it has a SIGSTOP pending\n",
|
|
lwpid_of (thread));
|
|
|
|
send_sigstop (lwp);
|
|
}
|
|
|
|
if (thread->last_resume_kind == resume_step)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf (" stepping LWP %ld, client wants it stepping\n",
|
|
lwpid_of (thread));
|
|
|
|
/* If resume_step is requested by GDB, install single-step
|
|
breakpoints when the thread is about to be actually resumed if
|
|
the single-step breakpoints weren't removed. */
|
|
if (can_software_single_step ()
|
|
&& !has_single_step_breakpoints (thread))
|
|
install_software_single_step_breakpoints (lwp);
|
|
|
|
step = maybe_hw_step (thread);
|
|
}
|
|
else if (lwp->bp_reinsert != 0)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf (" stepping LWP %ld, reinsert set\n",
|
|
lwpid_of (thread));
|
|
|
|
step = maybe_hw_step (thread);
|
|
}
|
|
else
|
|
step = 0;
|
|
|
|
linux_resume_one_lwp (lwp, step, 0, NULL);
|
|
}
|
|
|
|
static void
|
|
unsuspend_and_proceed_one_lwp (thread_info *thread, lwp_info *except)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (thread);
|
|
|
|
if (lwp == except)
|
|
return;
|
|
|
|
lwp_suspended_decr (lwp);
|
|
|
|
proceed_one_lwp (thread, except);
|
|
}
|
|
|
|
/* When we finish a step-over, set threads running again. If there's
|
|
another thread that may need a step-over, now's the time to start
|
|
it. Eventually, we'll move all threads past their breakpoints. */
|
|
|
|
static void
|
|
proceed_all_lwps (void)
|
|
{
|
|
struct thread_info *need_step_over;
|
|
|
|
/* If there is a thread which would otherwise be resumed, which is
|
|
stopped at a breakpoint that needs stepping over, then don't
|
|
resume any threads - have it step over the breakpoint with all
|
|
other threads stopped, then resume all threads again. */
|
|
|
|
if (supports_breakpoints ())
|
|
{
|
|
need_step_over = find_thread (need_step_over_p);
|
|
|
|
if (need_step_over != NULL)
|
|
{
|
|
if (debug_threads)
|
|
debug_printf ("proceed_all_lwps: found "
|
|
"thread %ld needing a step-over\n",
|
|
lwpid_of (need_step_over));
|
|
|
|
start_step_over (get_thread_lwp (need_step_over));
|
|
return;
|
|
}
|
|
}
|
|
|
|
if (debug_threads)
|
|
debug_printf ("Proceeding, no step-over needed\n");
|
|
|
|
for_each_thread ([] (thread_info *thread)
|
|
{
|
|
proceed_one_lwp (thread, NULL);
|
|
});
|
|
}
|
|
|
|
/* Stopped LWPs that the client wanted to be running, that don't have
|
|
pending statuses, are set to run again, except for EXCEPT, if not
|
|
NULL. This undoes a stop_all_lwps call. */
|
|
|
|
static void
|
|
unstop_all_lwps (int unsuspend, struct lwp_info *except)
|
|
{
|
|
if (debug_threads)
|
|
{
|
|
debug_enter ();
|
|
if (except)
|
|
debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
|
|
lwpid_of (get_lwp_thread (except)));
|
|
else
|
|
debug_printf ("unstopping all lwps\n");
|
|
}
|
|
|
|
if (unsuspend)
|
|
for_each_thread ([&] (thread_info *thread)
|
|
{
|
|
unsuspend_and_proceed_one_lwp (thread, except);
|
|
});
|
|
else
|
|
for_each_thread ([&] (thread_info *thread)
|
|
{
|
|
proceed_one_lwp (thread, except);
|
|
});
|
|
|
|
if (debug_threads)
|
|
{
|
|
debug_printf ("unstop_all_lwps done\n");
|
|
debug_exit ();
|
|
}
|
|
}
|
|
|
|
|
|
#ifdef HAVE_LINUX_REGSETS
|
|
|
|
#define use_linux_regsets 1
|
|
|
|
/* Returns true if REGSET has been disabled. */
|
|
|
|
static int
|
|
regset_disabled (struct regsets_info *info, struct regset_info *regset)
|
|
{
|
|
return (info->disabled_regsets != NULL
|
|
&& info->disabled_regsets[regset - info->regsets]);
|
|
}
|
|
|
|
/* Disable REGSET. */
|
|
|
|
static void
|
|
disable_regset (struct regsets_info *info, struct regset_info *regset)
|
|
{
|
|
int dr_offset;
|
|
|
|
dr_offset = regset - info->regsets;
|
|
if (info->disabled_regsets == NULL)
|
|
info->disabled_regsets = (char *) xcalloc (1, info->num_regsets);
|
|
info->disabled_regsets[dr_offset] = 1;
|
|
}
|
|
|
|
static int
|
|
regsets_fetch_inferior_registers (struct regsets_info *regsets_info,
|
|
struct regcache *regcache)
|
|
{
|
|
struct regset_info *regset;
|
|
int saw_general_regs = 0;
|
|
int pid;
|
|
struct iovec iov;
|
|
|
|
pid = lwpid_of (current_thread);
|
|
for (regset = regsets_info->regsets; regset->size >= 0; regset++)
|
|
{
|
|
void *buf, *data;
|
|
int nt_type, res;
|
|
|
|
if (regset->size == 0 || regset_disabled (regsets_info, regset))
|
|
continue;
|
|
|
|
buf = xmalloc (regset->size);
|
|
|
|
nt_type = regset->nt_type;
|
|
if (nt_type)
|
|
{
|
|
iov.iov_base = buf;
|
|
iov.iov_len = regset->size;
|
|
data = (void *) &iov;
|
|
}
|
|
else
|
|
data = buf;
|
|
|
|
#ifndef __sparc__
|
|
res = ptrace (regset->get_request, pid,
|
|
(PTRACE_TYPE_ARG3) (long) nt_type, data);
|
|
#else
|
|
res = ptrace (regset->get_request, pid, data, nt_type);
|
|
#endif
|
|
if (res < 0)
|
|
{
|
|
if (errno == EIO)
|
|
{
|
|
/* If we get EIO on a regset, do not try it again for
|
|
this process mode. */
|
|
disable_regset (regsets_info, regset);
|
|
}
|
|
else if (errno == ENODATA)
|
|
{
|
|
/* ENODATA may be returned if the regset is currently
|
|
not "active". This can happen in normal operation,
|
|
so suppress the warning in this case. */
|
|
}
|
|
else if (errno == ESRCH)
|
|
{
|
|
/* At this point, ESRCH should mean the process is
|
|
already gone, in which case we simply ignore attempts
|
|
to read its registers. */
|
|
}
|
|
else
|
|
{
|
|
char s[256];
|
|
sprintf (s, "ptrace(regsets_fetch_inferior_registers) PID=%d",
|
|
pid);
|
|
perror (s);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (regset->type == GENERAL_REGS)
|
|
saw_general_regs = 1;
|
|
regset->store_function (regcache, buf);
|
|
}
|
|
free (buf);
|
|
}
|
|
if (saw_general_regs)
|
|
return 0;
|
|
else
|
|
return 1;
|
|
}
|
|
|
|
static int
|
|
regsets_store_inferior_registers (struct regsets_info *regsets_info,
|
|
struct regcache *regcache)
|
|
{
|
|
struct regset_info *regset;
|
|
int saw_general_regs = 0;
|
|
int pid;
|
|
struct iovec iov;
|
|
|
|
pid = lwpid_of (current_thread);
|
|
for (regset = regsets_info->regsets; regset->size >= 0; regset++)
|
|
{
|
|
void *buf, *data;
|
|
int nt_type, res;
|
|
|
|
if (regset->size == 0 || regset_disabled (regsets_info, regset)
|
|
|| regset->fill_function == NULL)
|
|
continue;
|
|
|
|
buf = xmalloc (regset->size);
|
|
|
|
/* First fill the buffer with the current register set contents,
|
|
in case there are any items in the kernel's regset that are
|
|
not in gdbserver's regcache. */
|
|
|
|
nt_type = regset->nt_type;
|
|
if (nt_type)
|
|
{
|
|
iov.iov_base = buf;
|
|
iov.iov_len = regset->size;
|
|
data = (void *) &iov;
|
|
}
|
|
else
|
|
data = buf;
|
|
|
|
#ifndef __sparc__
|
|
res = ptrace (regset->get_request, pid,
|
|
(PTRACE_TYPE_ARG3) (long) nt_type, data);
|
|
#else
|
|
res = ptrace (regset->get_request, pid, data, nt_type);
|
|
#endif
|
|
|
|
if (res == 0)
|
|
{
|
|
/* Then overlay our cached registers on that. */
|
|
regset->fill_function (regcache, buf);
|
|
|
|
/* Only now do we write the register set. */
|
|
#ifndef __sparc__
|
|
res = ptrace (regset->set_request, pid,
|
|
(PTRACE_TYPE_ARG3) (long) nt_type, data);
|
|
#else
|
|
res = ptrace (regset->set_request, pid, data, nt_type);
|
|
#endif
|
|
}
|
|
|
|
if (res < 0)
|
|
{
|
|
if (errno == EIO)
|
|
{
|
|
/* If we get EIO on a regset, do not try it again for
|
|
this process mode. */
|
|
disable_regset (regsets_info, regset);
|
|
}
|
|
else if (errno == ESRCH)
|
|
{
|
|
/* At this point, ESRCH should mean the process is
|
|
already gone, in which case we simply ignore attempts
|
|
to change its registers. See also the related
|
|
comment in linux_resume_one_lwp. */
|
|
free (buf);
|
|
return 0;
|
|
}
|
|
else
|
|
{
|
|
perror ("Warning: ptrace(regsets_store_inferior_registers)");
|
|
}
|
|
}
|
|
else if (regset->type == GENERAL_REGS)
|
|
saw_general_regs = 1;
|
|
free (buf);
|
|
}
|
|
if (saw_general_regs)
|
|
return 0;
|
|
else
|
|
return 1;
|
|
}
|
|
|
|
#else /* !HAVE_LINUX_REGSETS */
|
|
|
|
#define use_linux_regsets 0
|
|
#define regsets_fetch_inferior_registers(regsets_info, regcache) 1
|
|
#define regsets_store_inferior_registers(regsets_info, regcache) 1
|
|
|
|
#endif
|
|
|
|
/* Return 1 if register REGNO is supported by one of the regset ptrace
|
|
calls or 0 if it has to be transferred individually. */
|
|
|
|
static int
|
|
linux_register_in_regsets (const struct regs_info *regs_info, int regno)
|
|
{
|
|
unsigned char mask = 1 << (regno % 8);
|
|
size_t index = regno / 8;
|
|
|
|
return (use_linux_regsets
|
|
&& (regs_info->regset_bitmap == NULL
|
|
|| (regs_info->regset_bitmap[index] & mask) != 0));
|
|
}
|
|
|
|
#ifdef HAVE_LINUX_USRREGS
|
|
|
|
static int
|
|
register_addr (const struct usrregs_info *usrregs, int regnum)
|
|
{
|
|
int addr;
|
|
|
|
if (regnum < 0 || regnum >= usrregs->num_regs)
|
|
error ("Invalid register number %d.", regnum);
|
|
|
|
addr = usrregs->regmap[regnum];
|
|
|
|
return addr;
|
|
}
|
|
|
|
/* Fetch one register. */
|
|
static void
|
|
fetch_register (const struct usrregs_info *usrregs,
|
|
struct regcache *regcache, int regno)
|
|
{
|
|
CORE_ADDR regaddr;
|
|
int i, size;
|
|
char *buf;
|
|
int pid;
|
|
|
|
if (regno >= usrregs->num_regs)
|
|
return;
|
|
if ((*the_low_target.cannot_fetch_register) (regno))
|
|
return;
|
|
|
|
regaddr = register_addr (usrregs, regno);
|
|
if (regaddr == -1)
|
|
return;
|
|
|
|
size = ((register_size (regcache->tdesc, regno)
|
|
+ sizeof (PTRACE_XFER_TYPE) - 1)
|
|
& -sizeof (PTRACE_XFER_TYPE));
|
|
buf = (char *) alloca (size);
|
|
|
|
pid = lwpid_of (current_thread);
|
|
for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
|
|
{
|
|
errno = 0;
|
|
*(PTRACE_XFER_TYPE *) (buf + i) =
|
|
ptrace (PTRACE_PEEKUSER, pid,
|
|
/* Coerce to a uintptr_t first to avoid potential gcc warning
|
|
of coercing an 8 byte integer to a 4 byte pointer. */
|
|
(PTRACE_TYPE_ARG3) (uintptr_t) regaddr, (PTRACE_TYPE_ARG4) 0);
|
|
regaddr += sizeof (PTRACE_XFER_TYPE);
|
|
if (errno != 0)
|
|
error ("reading register %d: %s", regno, strerror (errno));
|
|
}
|
|
|
|
if (the_low_target.supply_ptrace_register)
|
|
the_low_target.supply_ptrace_register (regcache, regno, buf);
|
|
else
|
|
supply_register (regcache, regno, buf);
|
|
}
|
|
|
|
/* Store one register. */
|
|
static void
|
|
store_register (const struct usrregs_info *usrregs,
|
|
struct regcache *regcache, int regno)
|
|
{
|
|
CORE_ADDR regaddr;
|
|
int i, size;
|
|
char *buf;
|
|
int pid;
|
|
|
|
if (regno >= usrregs->num_regs)
|
|
return;
|
|
if ((*the_low_target.cannot_store_register) (regno))
|
|
return;
|
|
|
|
regaddr = register_addr (usrregs, regno);
|
|
if (regaddr == -1)
|
|
return;
|
|
|
|
size = ((register_size (regcache->tdesc, regno)
|
|
+ sizeof (PTRACE_XFER_TYPE) - 1)
|
|
& -sizeof (PTRACE_XFER_TYPE));
|
|
buf = (char *) alloca (size);
|
|
memset (buf, 0, size);
|
|
|
|
if (the_low_target.collect_ptrace_register)
|
|
the_low_target.collect_ptrace_register (regcache, regno, buf);
|
|
else
|
|
collect_register (regcache, regno, buf);
|
|
|
|
pid = lwpid_of (current_thread);
|
|
for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
|
|
{
|
|
errno = 0;
|
|
ptrace (PTRACE_POKEUSER, pid,
|
|
/* Coerce to a uintptr_t first to avoid potential gcc warning
|
|
about coercing an 8 byte integer to a 4 byte pointer. */
|
|
(PTRACE_TYPE_ARG3) (uintptr_t) regaddr,
|
|
(PTRACE_TYPE_ARG4) *(PTRACE_XFER_TYPE *) (buf + i));
|
|
if (errno != 0)
|
|
{
|
|
/* At this point, ESRCH should mean the process is
|
|
already gone, in which case we simply ignore attempts
|
|
to change its registers. See also the related
|
|
comment in linux_resume_one_lwp. */
|
|
if (errno == ESRCH)
|
|
return;
|
|
|
|
if ((*the_low_target.cannot_store_register) (regno) == 0)
|
|
error ("writing register %d: %s", regno, strerror (errno));
|
|
}
|
|
regaddr += sizeof (PTRACE_XFER_TYPE);
|
|
}
|
|
}
|
|
|
|
/* Fetch all registers, or just one, from the child process.
|
|
If REGNO is -1, do this for all registers, skipping any that are
|
|
assumed to have been retrieved by regsets_fetch_inferior_registers,
|
|
unless ALL is non-zero.
|
|
Otherwise, REGNO specifies which register (so we can save time). */
|
|
static void
|
|
usr_fetch_inferior_registers (const struct regs_info *regs_info,
|
|
struct regcache *regcache, int regno, int all)
|
|
{
|
|
struct usrregs_info *usr = regs_info->usrregs;
|
|
|
|
if (regno == -1)
|
|
{
|
|
for (regno = 0; regno < usr->num_regs; regno++)
|
|
if (all || !linux_register_in_regsets (regs_info, regno))
|
|
fetch_register (usr, regcache, regno);
|
|
}
|
|
else
|
|
fetch_register (usr, regcache, regno);
|
|
}
|
|
|
|
/* Store our register values back into the inferior.
|
|
If REGNO is -1, do this for all registers, skipping any that are
|
|
assumed to have been saved by regsets_store_inferior_registers,
|
|
unless ALL is non-zero.
|
|
Otherwise, REGNO specifies which register (so we can save time). */
|
|
static void
|
|
usr_store_inferior_registers (const struct regs_info *regs_info,
|
|
struct regcache *regcache, int regno, int all)
|
|
{
|
|
struct usrregs_info *usr = regs_info->usrregs;
|
|
|
|
if (regno == -1)
|
|
{
|
|
for (regno = 0; regno < usr->num_regs; regno++)
|
|
if (all || !linux_register_in_regsets (regs_info, regno))
|
|
store_register (usr, regcache, regno);
|
|
}
|
|
else
|
|
store_register (usr, regcache, regno);
|
|
}
|
|
|
|
#else /* !HAVE_LINUX_USRREGS */
|
|
|
|
#define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
|
|
#define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
|
|
|
|
#endif
|
|
|
|
|
|
static void
|
|
linux_fetch_registers (struct regcache *regcache, int regno)
|
|
{
|
|
int use_regsets;
|
|
int all = 0;
|
|
const struct regs_info *regs_info = (*the_low_target.regs_info) ();
|
|
|
|
if (regno == -1)
|
|
{
|
|
if (the_low_target.fetch_register != NULL
|
|
&& regs_info->usrregs != NULL)
|
|
for (regno = 0; regno < regs_info->usrregs->num_regs; regno++)
|
|
(*the_low_target.fetch_register) (regcache, regno);
|
|
|
|
all = regsets_fetch_inferior_registers (regs_info->regsets_info, regcache);
|
|
if (regs_info->usrregs != NULL)
|
|
usr_fetch_inferior_registers (regs_info, regcache, -1, all);
|
|
}
|
|
else
|
|
{
|
|
if (the_low_target.fetch_register != NULL
|
|
&& (*the_low_target.fetch_register) (regcache, regno))
|
|
return;
|
|
|
|
use_regsets = linux_register_in_regsets (regs_info, regno);
|
|
if (use_regsets)
|
|
all = regsets_fetch_inferior_registers (regs_info->regsets_info,
|
|
regcache);
|
|
if ((!use_regsets || all) && regs_info->usrregs != NULL)
|
|
usr_fetch_inferior_registers (regs_info, regcache, regno, 1);
|
|
}
|
|
}
|
|
|
|
static void
|
|
linux_store_registers (struct regcache *regcache, int regno)
|
|
{
|
|
int use_regsets;
|
|
int all = 0;
|
|
const struct regs_info *regs_info = (*the_low_target.regs_info) ();
|
|
|
|
if (regno == -1)
|
|
{
|
|
all = regsets_store_inferior_registers (regs_info->regsets_info,
|
|
regcache);
|
|
if (regs_info->usrregs != NULL)
|
|
usr_store_inferior_registers (regs_info, regcache, regno, all);
|
|
}
|
|
else
|
|
{
|
|
use_regsets = linux_register_in_regsets (regs_info, regno);
|
|
if (use_regsets)
|
|
all = regsets_store_inferior_registers (regs_info->regsets_info,
|
|
regcache);
|
|
if ((!use_regsets || all) && regs_info->usrregs != NULL)
|
|
usr_store_inferior_registers (regs_info, regcache, regno, 1);
|
|
}
|
|
}
|
|
|
|
|
|
/* Copy LEN bytes from inferior's memory starting at MEMADDR
|
|
to debugger memory starting at MYADDR. */
|
|
|
|
static int
|
|
linux_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
|
|
{
|
|
int pid = lwpid_of (current_thread);
|
|
PTRACE_XFER_TYPE *buffer;
|
|
CORE_ADDR addr;
|
|
int count;
|
|
char filename[64];
|
|
int i;
|
|
int ret;
|
|
int fd;
|
|
|
|
/* Try using /proc. Don't bother for one word. */
|
|
if (len >= 3 * sizeof (long))
|
|
{
|
|
int bytes;
|
|
|
|
/* We could keep this file open and cache it - possibly one per
|
|
thread. That requires some juggling, but is even faster. */
|
|
sprintf (filename, "/proc/%d/mem", pid);
|
|
fd = open (filename, O_RDONLY | O_LARGEFILE);
|
|
if (fd == -1)
|
|
goto no_proc;
|
|
|
|
/* If pread64 is available, use it. It's faster if the kernel
|
|
supports it (only one syscall), and it's 64-bit safe even on
|
|
32-bit platforms (for instance, SPARC debugging a SPARC64
|
|
application). */
|
|
#ifdef HAVE_PREAD64
|
|
bytes = pread64 (fd, myaddr, len, memaddr);
|
|
#else
|
|
bytes = -1;
|
|
if (lseek (fd, memaddr, SEEK_SET) != -1)
|
|
bytes = read (fd, myaddr, len);
|
|
#endif
|
|
|
|
close (fd);
|
|
if (bytes == len)
|
|
return 0;
|
|
|
|
/* Some data was read, we'll try to get the rest with ptrace. */
|
|
if (bytes > 0)
|
|
{
|
|
memaddr += bytes;
|
|
myaddr += bytes;
|
|
len -= bytes;
|
|
}
|
|
}
|
|
|
|
no_proc:
|
|
/* Round starting address down to longword boundary. */
|
|
addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
|
|
/* Round ending address up; get number of longwords that makes. */
|
|
count = ((((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
|
|
/ sizeof (PTRACE_XFER_TYPE));
|
|
/* Allocate buffer of that many longwords. */
|
|
buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count);
|
|
|
|
/* Read all the longwords */
|
|
errno = 0;
|
|
for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
|
|
{
|
|
/* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
|
|
about coercing an 8 byte integer to a 4 byte pointer. */
|
|
buffer[i] = ptrace (PTRACE_PEEKTEXT, pid,
|
|
(PTRACE_TYPE_ARG3) (uintptr_t) addr,
|
|
(PTRACE_TYPE_ARG4) 0);
|
|
if (errno)
|
|
break;
|
|
}
|
|
ret = errno;
|
|
|
|
/* Copy appropriate bytes out of the buffer. */
|
|
if (i > 0)
|
|
{
|
|
i *= sizeof (PTRACE_XFER_TYPE);
|
|
i -= memaddr & (sizeof (PTRACE_XFER_TYPE) - 1);
|
|
memcpy (myaddr,
|
|
(char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
|
|
i < len ? i : len);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
|
|
memory at MEMADDR. On failure (cannot write to the inferior)
|
|
returns the value of errno. Always succeeds if LEN is zero. */
|
|
|
|
static int
|
|
linux_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len)
|
|
{
|
|
int i;
|
|
/* Round starting address down to longword boundary. */
|
|
CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
|
|
/* Round ending address up; get number of longwords that makes. */
|
|
int count
|
|
= (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
|
|
/ sizeof (PTRACE_XFER_TYPE);
|
|
|
|
/* Allocate buffer of that many longwords. */
|
|
PTRACE_XFER_TYPE *buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count);
|
|
|
|
int pid = lwpid_of (current_thread);
|
|
|
|
if (len == 0)
|
|
{
|
|
/* Zero length write always succeeds. */
|
|
return 0;
|
|
}
|
|
|
|
if (debug_threads)
|
|
{
|
|
/* Dump up to four bytes. */
|
|
char str[4 * 2 + 1];
|
|
char *p = str;
|
|
int dump = len < 4 ? len : 4;
|
|
|
|
for (i = 0; i < dump; i++)
|
|
{
|
|
sprintf (p, "%02x", myaddr[i]);
|
|
p += 2;
|
|
}
|
|
*p = '\0';
|
|
|
|
debug_printf ("Writing %s to 0x%08lx in process %d\n",
|
|
str, (long) memaddr, pid);
|
|
}
|
|
|
|
/* Fill start and end extra bytes of buffer with existing memory data. */
|
|
|
|
errno = 0;
|
|
/* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
|
|
about coercing an 8 byte integer to a 4 byte pointer. */
|
|
buffer[0] = ptrace (PTRACE_PEEKTEXT, pid,
|
|
(PTRACE_TYPE_ARG3) (uintptr_t) addr,
|
|
(PTRACE_TYPE_ARG4) 0);
|
|
if (errno)
|
|
return errno;
|
|
|
|
if (count > 1)
|
|
{
|
|
errno = 0;
|
|
buffer[count - 1]
|
|
= ptrace (PTRACE_PEEKTEXT, pid,
|
|
/* Coerce to a uintptr_t first to avoid potential gcc warning
|
|
about coercing an 8 byte integer to a 4 byte pointer. */
|
|
(PTRACE_TYPE_ARG3) (uintptr_t) (addr + (count - 1)
|
|
* sizeof (PTRACE_XFER_TYPE)),
|
|
(PTRACE_TYPE_ARG4) 0);
|
|
if (errno)
|
|
return errno;
|
|
}
|
|
|
|
/* Copy data to be written over corresponding part of buffer. */
|
|
|
|
memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
|
|
myaddr, len);
|
|
|
|
/* Write the entire buffer. */
|
|
|
|
for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
|
|
{
|
|
errno = 0;
|
|
ptrace (PTRACE_POKETEXT, pid,
|
|
/* Coerce to a uintptr_t first to avoid potential gcc warning
|
|
about coercing an 8 byte integer to a 4 byte pointer. */
|
|
(PTRACE_TYPE_ARG3) (uintptr_t) addr,
|
|
(PTRACE_TYPE_ARG4) buffer[i]);
|
|
if (errno)
|
|
return errno;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
linux_look_up_symbols (void)
|
|
{
|
|
#ifdef USE_THREAD_DB
|
|
struct process_info *proc = current_process ();
|
|
|
|
if (proc->priv->thread_db != NULL)
|
|
return;
|
|
|
|
thread_db_init ();
|
|
#endif
|
|
}
|
|
|
|
static void
|
|
linux_request_interrupt (void)
|
|
{
|
|
/* Send a SIGINT to the process group. This acts just like the user
|
|
typed a ^C on the controlling terminal. */
|
|
kill (-signal_pid, SIGINT);
|
|
}
|
|
|
|
/* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
|
|
to debugger memory starting at MYADDR. */
|
|
|
|
static int
|
|
linux_read_auxv (CORE_ADDR offset, unsigned char *myaddr, unsigned int len)
|
|
{
|
|
char filename[PATH_MAX];
|
|
int fd, n;
|
|
int pid = lwpid_of (current_thread);
|
|
|
|
xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
|
|
|
|
fd = open (filename, O_RDONLY);
|
|
if (fd < 0)
|
|
return -1;
|
|
|
|
if (offset != (CORE_ADDR) 0
|
|
&& lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
|
|
n = -1;
|
|
else
|
|
n = read (fd, myaddr, len);
|
|
|
|
close (fd);
|
|
|
|
return n;
|
|
}
|
|
|
|
/* These breakpoint and watchpoint related wrapper functions simply
|
|
pass on the function call if the target has registered a
|
|
corresponding function. */
|
|
|
|
static int
|
|
linux_supports_z_point_type (char z_type)
|
|
{
|
|
return (the_low_target.supports_z_point_type != NULL
|
|
&& the_low_target.supports_z_point_type (z_type));
|
|
}
|
|
|
|
static int
|
|
linux_insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
|
|
int size, struct raw_breakpoint *bp)
|
|
{
|
|
if (type == raw_bkpt_type_sw)
|
|
return insert_memory_breakpoint (bp);
|
|
else if (the_low_target.insert_point != NULL)
|
|
return the_low_target.insert_point (type, addr, size, bp);
|
|
else
|
|
/* Unsupported (see target.h). */
|
|
return 1;
|
|
}
|
|
|
|
static int
|
|
linux_remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
|
|
int size, struct raw_breakpoint *bp)
|
|
{
|
|
if (type == raw_bkpt_type_sw)
|
|
return remove_memory_breakpoint (bp);
|
|
else if (the_low_target.remove_point != NULL)
|
|
return the_low_target.remove_point (type, addr, size, bp);
|
|
else
|
|
/* Unsupported (see target.h). */
|
|
return 1;
|
|
}
|
|
|
|
/* Implement the to_stopped_by_sw_breakpoint target_ops
|
|
method. */
|
|
|
|
static int
|
|
linux_stopped_by_sw_breakpoint (void)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (current_thread);
|
|
|
|
return (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT);
|
|
}
|
|
|
|
/* Implement the to_supports_stopped_by_sw_breakpoint target_ops
|
|
method. */
|
|
|
|
static int
|
|
linux_supports_stopped_by_sw_breakpoint (void)
|
|
{
|
|
return USE_SIGTRAP_SIGINFO;
|
|
}
|
|
|
|
/* Implement the to_stopped_by_hw_breakpoint target_ops
|
|
method. */
|
|
|
|
static int
|
|
linux_stopped_by_hw_breakpoint (void)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (current_thread);
|
|
|
|
return (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT);
|
|
}
|
|
|
|
/* Implement the to_supports_stopped_by_hw_breakpoint target_ops
|
|
method. */
|
|
|
|
static int
|
|
linux_supports_stopped_by_hw_breakpoint (void)
|
|
{
|
|
return USE_SIGTRAP_SIGINFO;
|
|
}
|
|
|
|
/* Implement the supports_hardware_single_step target_ops method. */
|
|
|
|
static int
|
|
linux_supports_hardware_single_step (void)
|
|
{
|
|
return can_hardware_single_step ();
|
|
}
|
|
|
|
static int
|
|
linux_supports_software_single_step (void)
|
|
{
|
|
return can_software_single_step ();
|
|
}
|
|
|
|
static int
|
|
linux_stopped_by_watchpoint (void)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (current_thread);
|
|
|
|
return lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
|
|
}
|
|
|
|
static CORE_ADDR
|
|
linux_stopped_data_address (void)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (current_thread);
|
|
|
|
return lwp->stopped_data_address;
|
|
}
|
|
|
|
#if defined(__UCLIBC__) && defined(HAS_NOMMU) \
|
|
&& defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
|
|
&& defined(PT_TEXT_END_ADDR)
|
|
|
|
/* This is only used for targets that define PT_TEXT_ADDR,
|
|
PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
|
|
the target has different ways of acquiring this information, like
|
|
loadmaps. */
|
|
|
|
/* Under uClinux, programs are loaded at non-zero offsets, which we need
|
|
to tell gdb about. */
|
|
|
|
static int
|
|
linux_read_offsets (CORE_ADDR *text_p, CORE_ADDR *data_p)
|
|
{
|
|
unsigned long text, text_end, data;
|
|
int pid = lwpid_of (current_thread);
|
|
|
|
errno = 0;
|
|
|
|
text = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_ADDR,
|
|
(PTRACE_TYPE_ARG4) 0);
|
|
text_end = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_END_ADDR,
|
|
(PTRACE_TYPE_ARG4) 0);
|
|
data = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_DATA_ADDR,
|
|
(PTRACE_TYPE_ARG4) 0);
|
|
|
|
if (errno == 0)
|
|
{
|
|
/* Both text and data offsets produced at compile-time (and so
|
|
used by gdb) are relative to the beginning of the program,
|
|
with the data segment immediately following the text segment.
|
|
However, the actual runtime layout in memory may put the data
|
|
somewhere else, so when we send gdb a data base-address, we
|
|
use the real data base address and subtract the compile-time
|
|
data base-address from it (which is just the length of the
|
|
text segment). BSS immediately follows data in both
|
|
cases. */
|
|
*text_p = text;
|
|
*data_p = data - (text_end - text);
|
|
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static int
|
|
linux_qxfer_osdata (const char *annex,
|
|
unsigned char *readbuf, unsigned const char *writebuf,
|
|
CORE_ADDR offset, int len)
|
|
{
|
|
return linux_common_xfer_osdata (annex, readbuf, offset, len);
|
|
}
|
|
|
|
/* Convert a native/host siginfo object, into/from the siginfo in the
|
|
layout of the inferiors' architecture. */
|
|
|
|
static void
|
|
siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction)
|
|
{
|
|
int done = 0;
|
|
|
|
if (the_low_target.siginfo_fixup != NULL)
|
|
done = the_low_target.siginfo_fixup (siginfo, inf_siginfo, direction);
|
|
|
|
/* If there was no callback, or the callback didn't do anything,
|
|
then just do a straight memcpy. */
|
|
if (!done)
|
|
{
|
|
if (direction == 1)
|
|
memcpy (siginfo, inf_siginfo, sizeof (siginfo_t));
|
|
else
|
|
memcpy (inf_siginfo, siginfo, sizeof (siginfo_t));
|
|
}
|
|
}
|
|
|
|
static int
|
|
linux_xfer_siginfo (const char *annex, unsigned char *readbuf,
|
|
unsigned const char *writebuf, CORE_ADDR offset, int len)
|
|
{
|
|
int pid;
|
|
siginfo_t siginfo;
|
|
gdb_byte inf_siginfo[sizeof (siginfo_t)];
|
|
|
|
if (current_thread == NULL)
|
|
return -1;
|
|
|
|
pid = lwpid_of (current_thread);
|
|
|
|
if (debug_threads)
|
|
debug_printf ("%s siginfo for lwp %d.\n",
|
|
readbuf != NULL ? "Reading" : "Writing",
|
|
pid);
|
|
|
|
if (offset >= sizeof (siginfo))
|
|
return -1;
|
|
|
|
if (ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
|
|
return -1;
|
|
|
|
/* When GDBSERVER is built as a 64-bit application, ptrace writes into
|
|
SIGINFO an object with 64-bit layout. Since debugging a 32-bit
|
|
inferior with a 64-bit GDBSERVER should look the same as debugging it
|
|
with a 32-bit GDBSERVER, we need to convert it. */
|
|
siginfo_fixup (&siginfo, inf_siginfo, 0);
|
|
|
|
if (offset + len > sizeof (siginfo))
|
|
len = sizeof (siginfo) - offset;
|
|
|
|
if (readbuf != NULL)
|
|
memcpy (readbuf, inf_siginfo + offset, len);
|
|
else
|
|
{
|
|
memcpy (inf_siginfo + offset, writebuf, len);
|
|
|
|
/* Convert back to ptrace layout before flushing it out. */
|
|
siginfo_fixup (&siginfo, inf_siginfo, 1);
|
|
|
|
if (ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
|
|
return -1;
|
|
}
|
|
|
|
return len;
|
|
}
|
|
|
|
/* SIGCHLD handler that serves two purposes: In non-stop/async mode,
|
|
so we notice when children change state; as the handler for the
|
|
sigsuspend in my_waitpid. */
|
|
|
|
static void
|
|
sigchld_handler (int signo)
|
|
{
|
|
int old_errno = errno;
|
|
|
|
if (debug_threads)
|
|
{
|
|
do
|
|
{
|
|
/* fprintf is not async-signal-safe, so call write
|
|
directly. */
|
|
if (write (2, "sigchld_handler\n",
|
|
sizeof ("sigchld_handler\n") - 1) < 0)
|
|
break; /* just ignore */
|
|
} while (0);
|
|
}
|
|
|
|
if (target_is_async_p ())
|
|
async_file_mark (); /* trigger a linux_wait */
|
|
|
|
errno = old_errno;
|
|
}
|
|
|
|
static int
|
|
linux_supports_non_stop (void)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
static int
|
|
linux_async (int enable)
|
|
{
|
|
int previous = target_is_async_p ();
|
|
|
|
if (debug_threads)
|
|
debug_printf ("linux_async (%d), previous=%d\n",
|
|
enable, previous);
|
|
|
|
if (previous != enable)
|
|
{
|
|
sigset_t mask;
|
|
sigemptyset (&mask);
|
|
sigaddset (&mask, SIGCHLD);
|
|
|
|
sigprocmask (SIG_BLOCK, &mask, NULL);
|
|
|
|
if (enable)
|
|
{
|
|
if (pipe (linux_event_pipe) == -1)
|
|
{
|
|
linux_event_pipe[0] = -1;
|
|
linux_event_pipe[1] = -1;
|
|
sigprocmask (SIG_UNBLOCK, &mask, NULL);
|
|
|
|
warning ("creating event pipe failed.");
|
|
return previous;
|
|
}
|
|
|
|
fcntl (linux_event_pipe[0], F_SETFL, O_NONBLOCK);
|
|
fcntl (linux_event_pipe[1], F_SETFL, O_NONBLOCK);
|
|
|
|
/* Register the event loop handler. */
|
|
add_file_handler (linux_event_pipe[0],
|
|
handle_target_event, NULL);
|
|
|
|
/* Always trigger a linux_wait. */
|
|
async_file_mark ();
|
|
}
|
|
else
|
|
{
|
|
delete_file_handler (linux_event_pipe[0]);
|
|
|
|
close (linux_event_pipe[0]);
|
|
close (linux_event_pipe[1]);
|
|
linux_event_pipe[0] = -1;
|
|
linux_event_pipe[1] = -1;
|
|
}
|
|
|
|
sigprocmask (SIG_UNBLOCK, &mask, NULL);
|
|
}
|
|
|
|
return previous;
|
|
}
|
|
|
|
static int
|
|
linux_start_non_stop (int nonstop)
|
|
{
|
|
/* Register or unregister from event-loop accordingly. */
|
|
linux_async (nonstop);
|
|
|
|
if (target_is_async_p () != (nonstop != 0))
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
linux_supports_multi_process (void)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
/* Check if fork events are supported. */
|
|
|
|
static int
|
|
linux_supports_fork_events (void)
|
|
{
|
|
return linux_supports_tracefork ();
|
|
}
|
|
|
|
/* Check if vfork events are supported. */
|
|
|
|
static int
|
|
linux_supports_vfork_events (void)
|
|
{
|
|
return linux_supports_tracefork ();
|
|
}
|
|
|
|
/* Check if exec events are supported. */
|
|
|
|
static int
|
|
linux_supports_exec_events (void)
|
|
{
|
|
return linux_supports_traceexec ();
|
|
}
|
|
|
|
/* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
|
|
ptrace flags for all inferiors. This is in case the new GDB connection
|
|
doesn't support the same set of events that the previous one did. */
|
|
|
|
static void
|
|
linux_handle_new_gdb_connection (void)
|
|
{
|
|
/* Request that all the lwps reset their ptrace options. */
|
|
for_each_thread ([] (thread_info *thread)
|
|
{
|
|
struct lwp_info *lwp = get_thread_lwp (thread);
|
|
|
|
if (!lwp->stopped)
|
|
{
|
|
/* Stop the lwp so we can modify its ptrace options. */
|
|
lwp->must_set_ptrace_flags = 1;
|
|
linux_stop_lwp (lwp);
|
|
}
|
|
else
|
|
{
|
|
/* Already stopped; go ahead and set the ptrace options. */
|
|
struct process_info *proc = find_process_pid (pid_of (thread));
|
|
int options = linux_low_ptrace_options (proc->attached);
|
|
|
|
linux_enable_event_reporting (lwpid_of (thread), options);
|
|
lwp->must_set_ptrace_flags = 0;
|
|
}
|
|
});
|
|
}
|
|
|
|
static int
|
|
linux_supports_disable_randomization (void)
|
|
{
|
|
#ifdef HAVE_PERSONALITY
|
|
return 1;
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
static int
|
|
linux_supports_agent (void)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
static int
|
|
linux_supports_range_stepping (void)
|
|
{
|
|
if (can_software_single_step ())
|
|
return 1;
|
|
if (*the_low_target.supports_range_stepping == NULL)
|
|
return 0;
|
|
|
|
return (*the_low_target.supports_range_stepping) ();
|
|
}
|
|
|
|
/* Enumerate spufs IDs for process PID. */
|
|
static int
|
|
spu_enumerate_spu_ids (long pid, unsigned char *buf, CORE_ADDR offset, int len)
|
|
{
|
|
int pos = 0;
|
|
int written = 0;
|
|
char path[128];
|
|
DIR *dir;
|
|
struct dirent *entry;
|
|
|
|
sprintf (path, "/proc/%ld/fd", pid);
|
|
dir = opendir (path);
|
|
if (!dir)
|
|
return -1;
|
|
|
|
rewinddir (dir);
|
|
while ((entry = readdir (dir)) != NULL)
|
|
{
|
|
struct stat st;
|
|
struct statfs stfs;
|
|
int fd;
|
|
|
|
fd = atoi (entry->d_name);
|
|
if (!fd)
|
|
continue;
|
|
|
|
sprintf (path, "/proc/%ld/fd/%d", pid, fd);
|
|
if (stat (path, &st) != 0)
|
|
continue;
|
|
if (!S_ISDIR (st.st_mode))
|
|
continue;
|
|
|
|
if (statfs (path, &stfs) != 0)
|
|
continue;
|
|
if (stfs.f_type != SPUFS_MAGIC)
|
|
continue;
|
|
|
|
if (pos >= offset && pos + 4 <= offset + len)
|
|
{
|
|
*(unsigned int *)(buf + pos - offset) = fd;
|
|
written += 4;
|
|
}
|
|
pos += 4;
|
|
}
|
|
|
|
closedir (dir);
|
|
return written;
|
|
}
|
|
|
|
/* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
|
|
object type, using the /proc file system. */
|
|
static int
|
|
linux_qxfer_spu (const char *annex, unsigned char *readbuf,
|
|
unsigned const char *writebuf,
|
|
CORE_ADDR offset, int len)
|
|
{
|
|
long pid = lwpid_of (current_thread);
|
|
char buf[128];
|
|
int fd = 0;
|
|
int ret = 0;
|
|
|
|
if (!writebuf && !readbuf)
|
|
return -1;
|
|
|
|
if (!*annex)
|
|
{
|
|
if (!readbuf)
|
|
return -1;
|
|
else
|
|
return spu_enumerate_spu_ids (pid, readbuf, offset, len);
|
|
}
|
|
|
|
sprintf (buf, "/proc/%ld/fd/%s", pid, annex);
|
|
fd = open (buf, writebuf? O_WRONLY : O_RDONLY);
|
|
if (fd <= 0)
|
|
return -1;
|
|
|
|
if (offset != 0
|
|
&& lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
|
|
{
|
|
close (fd);
|
|
return 0;
|
|
}
|
|
|
|
if (writebuf)
|
|
ret = write (fd, writebuf, (size_t) len);
|
|
else
|
|
ret = read (fd, readbuf, (size_t) len);
|
|
|
|
close (fd);
|
|
return ret;
|
|
}
|
|
|
|
#if defined PT_GETDSBT || defined PTRACE_GETFDPIC
|
|
struct target_loadseg
|
|
{
|
|
/* Core address to which the segment is mapped. */
|
|
Elf32_Addr addr;
|
|
/* VMA recorded in the program header. */
|
|
Elf32_Addr p_vaddr;
|
|
/* Size of this segment in memory. */
|
|
Elf32_Word p_memsz;
|
|
};
|
|
|
|
# if defined PT_GETDSBT
|
|
struct target_loadmap
|
|
{
|
|
/* Protocol version number, must be zero. */
|
|
Elf32_Word version;
|
|
/* Pointer to the DSBT table, its size, and the DSBT index. */
|
|
unsigned *dsbt_table;
|
|
unsigned dsbt_size, dsbt_index;
|
|
/* Number of segments in this map. */
|
|
Elf32_Word nsegs;
|
|
/* The actual memory map. */
|
|
struct target_loadseg segs[/*nsegs*/];
|
|
};
|
|
# define LINUX_LOADMAP PT_GETDSBT
|
|
# define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
|
|
# define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
|
|
# else
|
|
struct target_loadmap
|
|
{
|
|
/* Protocol version number, must be zero. */
|
|
Elf32_Half version;
|
|
/* Number of segments in this map. */
|
|
Elf32_Half nsegs;
|
|
/* The actual memory map. */
|
|
struct target_loadseg segs[/*nsegs*/];
|
|
};
|
|
# define LINUX_LOADMAP PTRACE_GETFDPIC
|
|
# define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
|
|
# define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
|
|
# endif
|
|
|
|
static int
|
|
linux_read_loadmap (const char *annex, CORE_ADDR offset,
|
|
unsigned char *myaddr, unsigned int len)
|
|
{
|
|
int pid = lwpid_of (current_thread);
|
|
int addr = -1;
|
|
struct target_loadmap *data = NULL;
|
|
unsigned int actual_length, copy_length;
|
|
|
|
if (strcmp (annex, "exec") == 0)
|
|
addr = (int) LINUX_LOADMAP_EXEC;
|
|
else if (strcmp (annex, "interp") == 0)
|
|
addr = (int) LINUX_LOADMAP_INTERP;
|
|
else
|
|
return -1;
|
|
|
|
if (ptrace (LINUX_LOADMAP, pid, addr, &data) != 0)
|
|
return -1;
|
|
|
|
if (data == NULL)
|
|
return -1;
|
|
|
|
actual_length = sizeof (struct target_loadmap)
|
|
+ sizeof (struct target_loadseg) * data->nsegs;
|
|
|
|
if (offset < 0 || offset > actual_length)
|
|
return -1;
|
|
|
|
copy_length = actual_length - offset < len ? actual_length - offset : len;
|
|
memcpy (myaddr, (char *) data + offset, copy_length);
|
|
return copy_length;
|
|
}
|
|
#else
|
|
# define linux_read_loadmap NULL
|
|
#endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
|
|
|
|
static void
|
|
linux_process_qsupported (char **features, int count)
|
|
{
|
|
if (the_low_target.process_qsupported != NULL)
|
|
the_low_target.process_qsupported (features, count);
|
|
}
|
|
|
|
static int
|
|
linux_supports_catch_syscall (void)
|
|
{
|
|
return (the_low_target.get_syscall_trapinfo != NULL
|
|
&& linux_supports_tracesysgood ());
|
|
}
|
|
|
|
static int
|
|
linux_get_ipa_tdesc_idx (void)
|
|
{
|
|
if (the_low_target.get_ipa_tdesc_idx == NULL)
|
|
return 0;
|
|
|
|
return (*the_low_target.get_ipa_tdesc_idx) ();
|
|
}
|
|
|
|
static int
|
|
linux_supports_tracepoints (void)
|
|
{
|
|
if (*the_low_target.supports_tracepoints == NULL)
|
|
return 0;
|
|
|
|
return (*the_low_target.supports_tracepoints) ();
|
|
}
|
|
|
|
static CORE_ADDR
|
|
linux_read_pc (struct regcache *regcache)
|
|
{
|
|
if (the_low_target.get_pc == NULL)
|
|
return 0;
|
|
|
|
return (*the_low_target.get_pc) (regcache);
|
|
}
|
|
|
|
static void
|
|
linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
|
|
{
|
|
gdb_assert (the_low_target.set_pc != NULL);
|
|
|
|
(*the_low_target.set_pc) (regcache, pc);
|
|
}
|
|
|
|
static int
|
|
linux_thread_stopped (struct thread_info *thread)
|
|
{
|
|
return get_thread_lwp (thread)->stopped;
|
|
}
|
|
|
|
/* This exposes stop-all-threads functionality to other modules. */
|
|
|
|
static void
|
|
linux_pause_all (int freeze)
|
|
{
|
|
stop_all_lwps (freeze, NULL);
|
|
}
|
|
|
|
/* This exposes unstop-all-threads functionality to other gdbserver
|
|
modules. */
|
|
|
|
static void
|
|
linux_unpause_all (int unfreeze)
|
|
{
|
|
unstop_all_lwps (unfreeze, NULL);
|
|
}
|
|
|
|
static int
|
|
linux_prepare_to_access_memory (void)
|
|
{
|
|
/* Neither ptrace nor /proc/PID/mem allow accessing memory through a
|
|
running LWP. */
|
|
if (non_stop)
|
|
linux_pause_all (1);
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
linux_done_accessing_memory (void)
|
|
{
|
|
/* Neither ptrace nor /proc/PID/mem allow accessing memory through a
|
|
running LWP. */
|
|
if (non_stop)
|
|
linux_unpause_all (1);
|
|
}
|
|
|
|
static int
|
|
linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint, CORE_ADDR tpaddr,
|
|
CORE_ADDR collector,
|
|
CORE_ADDR lockaddr,
|
|
ULONGEST orig_size,
|
|
CORE_ADDR *jump_entry,
|
|
CORE_ADDR *trampoline,
|
|
ULONGEST *trampoline_size,
|
|
unsigned char *jjump_pad_insn,
|
|
ULONGEST *jjump_pad_insn_size,
|
|
CORE_ADDR *adjusted_insn_addr,
|
|
CORE_ADDR *adjusted_insn_addr_end,
|
|
char *err)
|
|
{
|
|
return (*the_low_target.install_fast_tracepoint_jump_pad)
|
|
(tpoint, tpaddr, collector, lockaddr, orig_size,
|
|
jump_entry, trampoline, trampoline_size,
|
|
jjump_pad_insn, jjump_pad_insn_size,
|
|
adjusted_insn_addr, adjusted_insn_addr_end,
|
|
err);
|
|
}
|
|
|
|
static struct emit_ops *
|
|
linux_emit_ops (void)
|
|
{
|
|
if (the_low_target.emit_ops != NULL)
|
|
return (*the_low_target.emit_ops) ();
|
|
else
|
|
return NULL;
|
|
}
|
|
|
|
static int
|
|
linux_get_min_fast_tracepoint_insn_len (void)
|
|
{
|
|
return (*the_low_target.get_min_fast_tracepoint_insn_len) ();
|
|
}
|
|
|
|
/* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
|
|
|
|
static int
|
|
get_phdr_phnum_from_proc_auxv (const int pid, const int is_elf64,
|
|
CORE_ADDR *phdr_memaddr, int *num_phdr)
|
|
{
|
|
char filename[PATH_MAX];
|
|
int fd;
|
|
const int auxv_size = is_elf64
|
|
? sizeof (Elf64_auxv_t) : sizeof (Elf32_auxv_t);
|
|
char buf[sizeof (Elf64_auxv_t)]; /* The larger of the two. */
|
|
|
|
xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
|
|
|
|
fd = open (filename, O_RDONLY);
|
|
if (fd < 0)
|
|
return 1;
|
|
|
|
*phdr_memaddr = 0;
|
|
*num_phdr = 0;
|
|
while (read (fd, buf, auxv_size) == auxv_size
|
|
&& (*phdr_memaddr == 0 || *num_phdr == 0))
|
|
{
|
|
if (is_elf64)
|
|
{
|
|
Elf64_auxv_t *const aux = (Elf64_auxv_t *) buf;
|
|
|
|
switch (aux->a_type)
|
|
{
|
|
case AT_PHDR:
|
|
*phdr_memaddr = aux->a_un.a_val;
|
|
break;
|
|
case AT_PHNUM:
|
|
*num_phdr = aux->a_un.a_val;
|
|
break;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
Elf32_auxv_t *const aux = (Elf32_auxv_t *) buf;
|
|
|
|
switch (aux->a_type)
|
|
{
|
|
case AT_PHDR:
|
|
*phdr_memaddr = aux->a_un.a_val;
|
|
break;
|
|
case AT_PHNUM:
|
|
*num_phdr = aux->a_un.a_val;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
close (fd);
|
|
|
|
if (*phdr_memaddr == 0 || *num_phdr == 0)
|
|
{
|
|
warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
|
|
"phdr_memaddr = %ld, phdr_num = %d",
|
|
(long) *phdr_memaddr, *num_phdr);
|
|
return 2;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
|
|
|
|
static CORE_ADDR
|
|
get_dynamic (const int pid, const int is_elf64)
|
|
{
|
|
CORE_ADDR phdr_memaddr, relocation;
|
|
int num_phdr, i;
|
|
unsigned char *phdr_buf;
|
|
const int phdr_size = is_elf64 ? sizeof (Elf64_Phdr) : sizeof (Elf32_Phdr);
|
|
|
|
if (get_phdr_phnum_from_proc_auxv (pid, is_elf64, &phdr_memaddr, &num_phdr))
|
|
return 0;
|
|
|
|
gdb_assert (num_phdr < 100); /* Basic sanity check. */
|
|
phdr_buf = (unsigned char *) alloca (num_phdr * phdr_size);
|
|
|
|
if (linux_read_memory (phdr_memaddr, phdr_buf, num_phdr * phdr_size))
|
|
return 0;
|
|
|
|
/* Compute relocation: it is expected to be 0 for "regular" executables,
|
|
non-zero for PIE ones. */
|
|
relocation = -1;
|
|
for (i = 0; relocation == -1 && i < num_phdr; i++)
|
|
if (is_elf64)
|
|
{
|
|
Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
|
|
|
|
if (p->p_type == PT_PHDR)
|
|
relocation = phdr_memaddr - p->p_vaddr;
|
|
}
|
|
else
|
|
{
|
|
Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
|
|
|
|
if (p->p_type == PT_PHDR)
|
|
relocation = phdr_memaddr - p->p_vaddr;
|
|
}
|
|
|
|
if (relocation == -1)
|
|
{
|
|
/* PT_PHDR is optional, but necessary for PIE in general. Fortunately
|
|
any real world executables, including PIE executables, have always
|
|
PT_PHDR present. PT_PHDR is not present in some shared libraries or
|
|
in fpc (Free Pascal 2.4) binaries but neither of those have a need for
|
|
or present DT_DEBUG anyway (fpc binaries are statically linked).
|
|
|
|
Therefore if there exists DT_DEBUG there is always also PT_PHDR.
|
|
|
|
GDB could find RELOCATION also from AT_ENTRY - e_entry. */
|
|
|
|
return 0;
|
|
}
|
|
|
|
for (i = 0; i < num_phdr; i++)
|
|
{
|
|
if (is_elf64)
|
|
{
|
|
Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
|
|
|
|
if (p->p_type == PT_DYNAMIC)
|
|
return p->p_vaddr + relocation;
|
|
}
|
|
else
|
|
{
|
|
Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
|
|
|
|
if (p->p_type == PT_DYNAMIC)
|
|
return p->p_vaddr + relocation;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Return &_r_debug in the inferior, or -1 if not present. Return value
|
|
can be 0 if the inferior does not yet have the library list initialized.
|
|
We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
|
|
DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
|
|
|
|
static CORE_ADDR
|
|
get_r_debug (const int pid, const int is_elf64)
|
|
{
|
|
CORE_ADDR dynamic_memaddr;
|
|
const int dyn_size = is_elf64 ? sizeof (Elf64_Dyn) : sizeof (Elf32_Dyn);
|
|
unsigned char buf[sizeof (Elf64_Dyn)]; /* The larger of the two. */
|
|
CORE_ADDR map = -1;
|
|
|
|
dynamic_memaddr = get_dynamic (pid, is_elf64);
|
|
if (dynamic_memaddr == 0)
|
|
return map;
|
|
|
|
while (linux_read_memory (dynamic_memaddr, buf, dyn_size) == 0)
|
|
{
|
|
if (is_elf64)
|
|
{
|
|
Elf64_Dyn *const dyn = (Elf64_Dyn *) buf;
|
|
#if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
|
|
union
|
|
{
|
|
Elf64_Xword map;
|
|
unsigned char buf[sizeof (Elf64_Xword)];
|
|
}
|
|
rld_map;
|
|
#endif
|
|
#ifdef DT_MIPS_RLD_MAP
|
|
if (dyn->d_tag == DT_MIPS_RLD_MAP)
|
|
{
|
|
if (linux_read_memory (dyn->d_un.d_val,
|
|
rld_map.buf, sizeof (rld_map.buf)) == 0)
|
|
return rld_map.map;
|
|
else
|
|
break;
|
|
}
|
|
#endif /* DT_MIPS_RLD_MAP */
|
|
#ifdef DT_MIPS_RLD_MAP_REL
|
|
if (dyn->d_tag == DT_MIPS_RLD_MAP_REL)
|
|
{
|
|
if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr,
|
|
rld_map.buf, sizeof (rld_map.buf)) == 0)
|
|
return rld_map.map;
|
|
else
|
|
break;
|
|
}
|
|
#endif /* DT_MIPS_RLD_MAP_REL */
|
|
|
|
if (dyn->d_tag == DT_DEBUG && map == -1)
|
|
map = dyn->d_un.d_val;
|
|
|
|
if (dyn->d_tag == DT_NULL)
|
|
break;
|
|
}
|
|
else
|
|
{
|
|
Elf32_Dyn *const dyn = (Elf32_Dyn *) buf;
|
|
#if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
|
|
union
|
|
{
|
|
Elf32_Word map;
|
|
unsigned char buf[sizeof (Elf32_Word)];
|
|
}
|
|
rld_map;
|
|
#endif
|
|
#ifdef DT_MIPS_RLD_MAP
|
|
if (dyn->d_tag == DT_MIPS_RLD_MAP)
|
|
{
|
|
if (linux_read_memory (dyn->d_un.d_val,
|
|
rld_map.buf, sizeof (rld_map.buf)) == 0)
|
|
return rld_map.map;
|
|
else
|
|
break;
|
|
}
|
|
#endif /* DT_MIPS_RLD_MAP */
|
|
#ifdef DT_MIPS_RLD_MAP_REL
|
|
if (dyn->d_tag == DT_MIPS_RLD_MAP_REL)
|
|
{
|
|
if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr,
|
|
rld_map.buf, sizeof (rld_map.buf)) == 0)
|
|
return rld_map.map;
|
|
else
|
|
break;
|
|
}
|
|
#endif /* DT_MIPS_RLD_MAP_REL */
|
|
|
|
if (dyn->d_tag == DT_DEBUG && map == -1)
|
|
map = dyn->d_un.d_val;
|
|
|
|
if (dyn->d_tag == DT_NULL)
|
|
break;
|
|
}
|
|
|
|
dynamic_memaddr += dyn_size;
|
|
}
|
|
|
|
return map;
|
|
}
|
|
|
|
/* Read one pointer from MEMADDR in the inferior. */
|
|
|
|
static int
|
|
read_one_ptr (CORE_ADDR memaddr, CORE_ADDR *ptr, int ptr_size)
|
|
{
|
|
int ret;
|
|
|
|
/* Go through a union so this works on either big or little endian
|
|
hosts, when the inferior's pointer size is smaller than the size
|
|
of CORE_ADDR. It is assumed the inferior's endianness is the
|
|
same of the superior's. */
|
|
union
|
|
{
|
|
CORE_ADDR core_addr;
|
|
unsigned int ui;
|
|
unsigned char uc;
|
|
} addr;
|
|
|
|
ret = linux_read_memory (memaddr, &addr.uc, ptr_size);
|
|
if (ret == 0)
|
|
{
|
|
if (ptr_size == sizeof (CORE_ADDR))
|
|
*ptr = addr.core_addr;
|
|
else if (ptr_size == sizeof (unsigned int))
|
|
*ptr = addr.ui;
|
|
else
|
|
gdb_assert_not_reached ("unhandled pointer size");
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
struct link_map_offsets
|
|
{
|
|
/* Offset and size of r_debug.r_version. */
|
|
int r_version_offset;
|
|
|
|
/* Offset and size of r_debug.r_map. */
|
|
int r_map_offset;
|
|
|
|
/* Offset to l_addr field in struct link_map. */
|
|
int l_addr_offset;
|
|
|
|
/* Offset to l_name field in struct link_map. */
|
|
int l_name_offset;
|
|
|
|
/* Offset to l_ld field in struct link_map. */
|
|
int l_ld_offset;
|
|
|
|
/* Offset to l_next field in struct link_map. */
|
|
int l_next_offset;
|
|
|
|
/* Offset to l_prev field in struct link_map. */
|
|
int l_prev_offset;
|
|
};
|
|
|
|
/* Construct qXfer:libraries-svr4:read reply. */
|
|
|
|
static int
|
|
linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf,
|
|
unsigned const char *writebuf,
|
|
CORE_ADDR offset, int len)
|
|
{
|
|
char *document;
|
|
unsigned document_len;
|
|
struct process_info_private *const priv = current_process ()->priv;
|
|
char filename[PATH_MAX];
|
|
int pid, is_elf64;
|
|
|
|
static const struct link_map_offsets lmo_32bit_offsets =
|
|
{
|
|
0, /* r_version offset. */
|
|
4, /* r_debug.r_map offset. */
|
|
0, /* l_addr offset in link_map. */
|
|
4, /* l_name offset in link_map. */
|
|
8, /* l_ld offset in link_map. */
|
|
12, /* l_next offset in link_map. */
|
|
16 /* l_prev offset in link_map. */
|
|
};
|
|
|
|
static const struct link_map_offsets lmo_64bit_offsets =
|
|
{
|
|
0, /* r_version offset. */
|
|
8, /* r_debug.r_map offset. */
|
|
0, /* l_addr offset in link_map. */
|
|
8, /* l_name offset in link_map. */
|
|
16, /* l_ld offset in link_map. */
|
|
24, /* l_next offset in link_map. */
|
|
32 /* l_prev offset in link_map. */
|
|
};
|
|
const struct link_map_offsets *lmo;
|
|
unsigned int machine;
|
|
int ptr_size;
|
|
CORE_ADDR lm_addr = 0, lm_prev = 0;
|
|
int allocated = 1024;
|
|
char *p;
|
|
CORE_ADDR l_name, l_addr, l_ld, l_next, l_prev;
|
|
int header_done = 0;
|
|
|
|
if (writebuf != NULL)
|
|
return -2;
|
|
if (readbuf == NULL)
|
|
return -1;
|
|
|
|
pid = lwpid_of (current_thread);
|
|
xsnprintf (filename, sizeof filename, "/proc/%d/exe", pid);
|
|
is_elf64 = elf_64_file_p (filename, &machine);
|
|
lmo = is_elf64 ? &lmo_64bit_offsets : &lmo_32bit_offsets;
|
|
ptr_size = is_elf64 ? 8 : 4;
|
|
|
|
while (annex[0] != '\0')
|
|
{
|
|
const char *sep;
|
|
CORE_ADDR *addrp;
|
|
int len;
|
|
|
|
sep = strchr (annex, '=');
|
|
if (sep == NULL)
|
|
break;
|
|
|
|
len = sep - annex;
|
|
if (len == 5 && startswith (annex, "start"))
|
|
addrp = &lm_addr;
|
|
else if (len == 4 && startswith (annex, "prev"))
|
|
addrp = &lm_prev;
|
|
else
|
|
{
|
|
annex = strchr (sep, ';');
|
|
if (annex == NULL)
|
|
break;
|
|
annex++;
|
|
continue;
|
|
}
|
|
|
|
annex = decode_address_to_semicolon (addrp, sep + 1);
|
|
}
|
|
|
|
if (lm_addr == 0)
|
|
{
|
|
int r_version = 0;
|
|
|
|
if (priv->r_debug == 0)
|
|
priv->r_debug = get_r_debug (pid, is_elf64);
|
|
|
|
/* We failed to find DT_DEBUG. Such situation will not change
|
|
for this inferior - do not retry it. Report it to GDB as
|
|
E01, see for the reasons at the GDB solib-svr4.c side. */
|
|
if (priv->r_debug == (CORE_ADDR) -1)
|
|
return -1;
|
|
|
|
if (priv->r_debug != 0)
|
|
{
|
|
if (linux_read_memory (priv->r_debug + lmo->r_version_offset,
|
|
(unsigned char *) &r_version,
|
|
sizeof (r_version)) != 0
|
|
|| r_version != 1)
|
|
{
|
|
warning ("unexpected r_debug version %d", r_version);
|
|
}
|
|
else if (read_one_ptr (priv->r_debug + lmo->r_map_offset,
|
|
&lm_addr, ptr_size) != 0)
|
|
{
|
|
warning ("unable to read r_map from 0x%lx",
|
|
(long) priv->r_debug + lmo->r_map_offset);
|
|
}
|
|
}
|
|
}
|
|
|
|
document = (char *) xmalloc (allocated);
|
|
strcpy (document, "<library-list-svr4 version=\"1.0\"");
|
|
p = document + strlen (document);
|
|
|
|
while (lm_addr
|
|
&& read_one_ptr (lm_addr + lmo->l_name_offset,
|
|
&l_name, ptr_size) == 0
|
|
&& read_one_ptr (lm_addr + lmo->l_addr_offset,
|
|
&l_addr, ptr_size) == 0
|
|
&& read_one_ptr (lm_addr + lmo->l_ld_offset,
|
|
&l_ld, ptr_size) == 0
|
|
&& read_one_ptr (lm_addr + lmo->l_prev_offset,
|
|
&l_prev, ptr_size) == 0
|
|
&& read_one_ptr (lm_addr + lmo->l_next_offset,
|
|
&l_next, ptr_size) == 0)
|
|
{
|
|
unsigned char libname[PATH_MAX];
|
|
|
|
if (lm_prev != l_prev)
|
|
{
|
|
warning ("Corrupted shared library list: 0x%lx != 0x%lx",
|
|
(long) lm_prev, (long) l_prev);
|
|
break;
|
|
}
|
|
|
|
/* Ignore the first entry even if it has valid name as the first entry
|
|
corresponds to the main executable. The first entry should not be
|
|
skipped if the dynamic loader was loaded late by a static executable
|
|
(see solib-svr4.c parameter ignore_first). But in such case the main
|
|
executable does not have PT_DYNAMIC present and this function already
|
|
exited above due to failed get_r_debug. */
|
|
if (lm_prev == 0)
|
|
{
|
|
sprintf (p, " main-lm=\"0x%lx\"", (unsigned long) lm_addr);
|
|
p = p + strlen (p);
|
|
}
|
|
else
|
|
{
|
|
/* Not checking for error because reading may stop before
|
|
we've got PATH_MAX worth of characters. */
|
|
libname[0] = '\0';
|
|
linux_read_memory (l_name, libname, sizeof (libname) - 1);
|
|
libname[sizeof (libname) - 1] = '\0';
|
|
if (libname[0] != '\0')
|
|
{
|
|
/* 6x the size for xml_escape_text below. */
|
|
size_t len = 6 * strlen ((char *) libname);
|
|
|
|
if (!header_done)
|
|
{
|
|
/* Terminate `<library-list-svr4'. */
|
|
*p++ = '>';
|
|
header_done = 1;
|
|
}
|
|
|
|
while (allocated < p - document + len + 200)
|
|
{
|
|
/* Expand to guarantee sufficient storage. */
|
|
uintptr_t document_len = p - document;
|
|
|
|
document = (char *) xrealloc (document, 2 * allocated);
|
|
allocated *= 2;
|
|
p = document + document_len;
|
|
}
|
|
|
|
std::string name = xml_escape_text ((char *) libname);
|
|
p += sprintf (p, "<library name=\"%s\" lm=\"0x%lx\" "
|
|
"l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
|
|
name.c_str (), (unsigned long) lm_addr,
|
|
(unsigned long) l_addr, (unsigned long) l_ld);
|
|
}
|
|
}
|
|
|
|
lm_prev = lm_addr;
|
|
lm_addr = l_next;
|
|
}
|
|
|
|
if (!header_done)
|
|
{
|
|
/* Empty list; terminate `<library-list-svr4'. */
|
|
strcpy (p, "/>");
|
|
}
|
|
else
|
|
strcpy (p, "</library-list-svr4>");
|
|
|
|
document_len = strlen (document);
|
|
if (offset < document_len)
|
|
document_len -= offset;
|
|
else
|
|
document_len = 0;
|
|
if (len > document_len)
|
|
len = document_len;
|
|
|
|
memcpy (readbuf, document + offset, len);
|
|
xfree (document);
|
|
|
|
return len;
|
|
}
|
|
|
|
#ifdef HAVE_LINUX_BTRACE
|
|
|
|
/* See to_disable_btrace target method. */
|
|
|
|
static int
|
|
linux_low_disable_btrace (struct btrace_target_info *tinfo)
|
|
{
|
|
enum btrace_error err;
|
|
|
|
err = linux_disable_btrace (tinfo);
|
|
return (err == BTRACE_ERR_NONE ? 0 : -1);
|
|
}
|
|
|
|
/* Encode an Intel Processor Trace configuration. */
|
|
|
|
static void
|
|
linux_low_encode_pt_config (struct buffer *buffer,
|
|
const struct btrace_data_pt_config *config)
|
|
{
|
|
buffer_grow_str (buffer, "<pt-config>\n");
|
|
|
|
switch (config->cpu.vendor)
|
|
{
|
|
case CV_INTEL:
|
|
buffer_xml_printf (buffer, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
|
|
"model=\"%u\" stepping=\"%u\"/>\n",
|
|
config->cpu.family, config->cpu.model,
|
|
config->cpu.stepping);
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
|
|
buffer_grow_str (buffer, "</pt-config>\n");
|
|
}
|
|
|
|
/* Encode a raw buffer. */
|
|
|
|
static void
|
|
linux_low_encode_raw (struct buffer *buffer, const gdb_byte *data,
|
|
unsigned int size)
|
|
{
|
|
if (size == 0)
|
|
return;
|
|
|
|
/* We use hex encoding - see common/rsp-low.h. */
|
|
buffer_grow_str (buffer, "<raw>\n");
|
|
|
|
while (size-- > 0)
|
|
{
|
|
char elem[2];
|
|
|
|
elem[0] = tohex ((*data >> 4) & 0xf);
|
|
elem[1] = tohex (*data++ & 0xf);
|
|
|
|
buffer_grow (buffer, elem, 2);
|
|
}
|
|
|
|
buffer_grow_str (buffer, "</raw>\n");
|
|
}
|
|
|
|
/* See to_read_btrace target method. */
|
|
|
|
static int
|
|
linux_low_read_btrace (struct btrace_target_info *tinfo, struct buffer *buffer,
|
|
enum btrace_read_type type)
|
|
{
|
|
struct btrace_data btrace;
|
|
struct btrace_block *block;
|
|
enum btrace_error err;
|
|
int i;
|
|
|
|
btrace_data_init (&btrace);
|
|
|
|
err = linux_read_btrace (&btrace, tinfo, type);
|
|
if (err != BTRACE_ERR_NONE)
|
|
{
|
|
if (err == BTRACE_ERR_OVERFLOW)
|
|
buffer_grow_str0 (buffer, "E.Overflow.");
|
|
else
|
|
buffer_grow_str0 (buffer, "E.Generic Error.");
|
|
|
|
goto err;
|
|
}
|
|
|
|
switch (btrace.format)
|
|
{
|
|
case BTRACE_FORMAT_NONE:
|
|
buffer_grow_str0 (buffer, "E.No Trace.");
|
|
goto err;
|
|
|
|
case BTRACE_FORMAT_BTS:
|
|
buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
|
|
buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
|
|
|
|
for (i = 0;
|
|
VEC_iterate (btrace_block_s, btrace.variant.bts.blocks, i, block);
|
|
i++)
|
|
buffer_xml_printf (buffer, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
|
|
paddress (block->begin), paddress (block->end));
|
|
|
|
buffer_grow_str0 (buffer, "</btrace>\n");
|
|
break;
|
|
|
|
case BTRACE_FORMAT_PT:
|
|
buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
|
|
buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
|
|
buffer_grow_str (buffer, "<pt>\n");
|
|
|
|
linux_low_encode_pt_config (buffer, &btrace.variant.pt.config);
|
|
|
|
linux_low_encode_raw (buffer, btrace.variant.pt.data,
|
|
btrace.variant.pt.size);
|
|
|
|
buffer_grow_str (buffer, "</pt>\n");
|
|
buffer_grow_str0 (buffer, "</btrace>\n");
|
|
break;
|
|
|
|
default:
|
|
buffer_grow_str0 (buffer, "E.Unsupported Trace Format.");
|
|
goto err;
|
|
}
|
|
|
|
btrace_data_fini (&btrace);
|
|
return 0;
|
|
|
|
err:
|
|
btrace_data_fini (&btrace);
|
|
return -1;
|
|
}
|
|
|
|
/* See to_btrace_conf target method. */
|
|
|
|
static int
|
|
linux_low_btrace_conf (const struct btrace_target_info *tinfo,
|
|
struct buffer *buffer)
|
|
{
|
|
const struct btrace_config *conf;
|
|
|
|
buffer_grow_str (buffer, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
|
|
buffer_grow_str (buffer, "<btrace-conf version=\"1.0\">\n");
|
|
|
|
conf = linux_btrace_conf (tinfo);
|
|
if (conf != NULL)
|
|
{
|
|
switch (conf->format)
|
|
{
|
|
case BTRACE_FORMAT_NONE:
|
|
break;
|
|
|
|
case BTRACE_FORMAT_BTS:
|
|
buffer_xml_printf (buffer, "<bts");
|
|
buffer_xml_printf (buffer, " size=\"0x%x\"", conf->bts.size);
|
|
buffer_xml_printf (buffer, " />\n");
|
|
break;
|
|
|
|
case BTRACE_FORMAT_PT:
|
|
buffer_xml_printf (buffer, "<pt");
|
|
buffer_xml_printf (buffer, " size=\"0x%x\"", conf->pt.size);
|
|
buffer_xml_printf (buffer, "/>\n");
|
|
break;
|
|
}
|
|
}
|
|
|
|
buffer_grow_str0 (buffer, "</btrace-conf>\n");
|
|
return 0;
|
|
}
|
|
#endif /* HAVE_LINUX_BTRACE */
|
|
|
|
/* See nat/linux-nat.h. */
|
|
|
|
ptid_t
|
|
current_lwp_ptid (void)
|
|
{
|
|
return ptid_of (current_thread);
|
|
}
|
|
|
|
/* Implementation of the target_ops method "breakpoint_kind_from_pc". */
|
|
|
|
static int
|
|
linux_breakpoint_kind_from_pc (CORE_ADDR *pcptr)
|
|
{
|
|
if (the_low_target.breakpoint_kind_from_pc != NULL)
|
|
return (*the_low_target.breakpoint_kind_from_pc) (pcptr);
|
|
else
|
|
return default_breakpoint_kind_from_pc (pcptr);
|
|
}
|
|
|
|
/* Implementation of the target_ops method "sw_breakpoint_from_kind". */
|
|
|
|
static const gdb_byte *
|
|
linux_sw_breakpoint_from_kind (int kind, int *size)
|
|
{
|
|
gdb_assert (the_low_target.sw_breakpoint_from_kind != NULL);
|
|
|
|
return (*the_low_target.sw_breakpoint_from_kind) (kind, size);
|
|
}
|
|
|
|
/* Implementation of the target_ops method
|
|
"breakpoint_kind_from_current_state". */
|
|
|
|
static int
|
|
linux_breakpoint_kind_from_current_state (CORE_ADDR *pcptr)
|
|
{
|
|
if (the_low_target.breakpoint_kind_from_current_state != NULL)
|
|
return (*the_low_target.breakpoint_kind_from_current_state) (pcptr);
|
|
else
|
|
return linux_breakpoint_kind_from_pc (pcptr);
|
|
}
|
|
|
|
/* Default implementation of linux_target_ops method "set_pc" for
|
|
32-bit pc register which is literally named "pc". */
|
|
|
|
void
|
|
linux_set_pc_32bit (struct regcache *regcache, CORE_ADDR pc)
|
|
{
|
|
uint32_t newpc = pc;
|
|
|
|
supply_register_by_name (regcache, "pc", &newpc);
|
|
}
|
|
|
|
/* Default implementation of linux_target_ops method "get_pc" for
|
|
32-bit pc register which is literally named "pc". */
|
|
|
|
CORE_ADDR
|
|
linux_get_pc_32bit (struct regcache *regcache)
|
|
{
|
|
uint32_t pc;
|
|
|
|
collect_register_by_name (regcache, "pc", &pc);
|
|
if (debug_threads)
|
|
debug_printf ("stop pc is 0x%" PRIx32 "\n", pc);
|
|
return pc;
|
|
}
|
|
|
|
/* Default implementation of linux_target_ops method "set_pc" for
|
|
64-bit pc register which is literally named "pc". */
|
|
|
|
void
|
|
linux_set_pc_64bit (struct regcache *regcache, CORE_ADDR pc)
|
|
{
|
|
uint64_t newpc = pc;
|
|
|
|
supply_register_by_name (regcache, "pc", &newpc);
|
|
}
|
|
|
|
/* Default implementation of linux_target_ops method "get_pc" for
|
|
64-bit pc register which is literally named "pc". */
|
|
|
|
CORE_ADDR
|
|
linux_get_pc_64bit (struct regcache *regcache)
|
|
{
|
|
uint64_t pc;
|
|
|
|
collect_register_by_name (regcache, "pc", &pc);
|
|
if (debug_threads)
|
|
debug_printf ("stop pc is 0x%" PRIx64 "\n", pc);
|
|
return pc;
|
|
}
|
|
|
|
|
|
static struct target_ops linux_target_ops = {
|
|
linux_create_inferior,
|
|
linux_post_create_inferior,
|
|
linux_attach,
|
|
linux_kill,
|
|
linux_detach,
|
|
linux_mourn,
|
|
linux_join,
|
|
linux_thread_alive,
|
|
linux_resume,
|
|
linux_wait,
|
|
linux_fetch_registers,
|
|
linux_store_registers,
|
|
linux_prepare_to_access_memory,
|
|
linux_done_accessing_memory,
|
|
linux_read_memory,
|
|
linux_write_memory,
|
|
linux_look_up_symbols,
|
|
linux_request_interrupt,
|
|
linux_read_auxv,
|
|
linux_supports_z_point_type,
|
|
linux_insert_point,
|
|
linux_remove_point,
|
|
linux_stopped_by_sw_breakpoint,
|
|
linux_supports_stopped_by_sw_breakpoint,
|
|
linux_stopped_by_hw_breakpoint,
|
|
linux_supports_stopped_by_hw_breakpoint,
|
|
linux_supports_hardware_single_step,
|
|
linux_stopped_by_watchpoint,
|
|
linux_stopped_data_address,
|
|
#if defined(__UCLIBC__) && defined(HAS_NOMMU) \
|
|
&& defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
|
|
&& defined(PT_TEXT_END_ADDR)
|
|
linux_read_offsets,
|
|
#else
|
|
NULL,
|
|
#endif
|
|
#ifdef USE_THREAD_DB
|
|
thread_db_get_tls_address,
|
|
#else
|
|
NULL,
|
|
#endif
|
|
linux_qxfer_spu,
|
|
hostio_last_error_from_errno,
|
|
linux_qxfer_osdata,
|
|
linux_xfer_siginfo,
|
|
linux_supports_non_stop,
|
|
linux_async,
|
|
linux_start_non_stop,
|
|
linux_supports_multi_process,
|
|
linux_supports_fork_events,
|
|
linux_supports_vfork_events,
|
|
linux_supports_exec_events,
|
|
linux_handle_new_gdb_connection,
|
|
#ifdef USE_THREAD_DB
|
|
thread_db_handle_monitor_command,
|
|
#else
|
|
NULL,
|
|
#endif
|
|
linux_common_core_of_thread,
|
|
linux_read_loadmap,
|
|
linux_process_qsupported,
|
|
linux_supports_tracepoints,
|
|
linux_read_pc,
|
|
linux_write_pc,
|
|
linux_thread_stopped,
|
|
NULL,
|
|
linux_pause_all,
|
|
linux_unpause_all,
|
|
linux_stabilize_threads,
|
|
linux_install_fast_tracepoint_jump_pad,
|
|
linux_emit_ops,
|
|
linux_supports_disable_randomization,
|
|
linux_get_min_fast_tracepoint_insn_len,
|
|
linux_qxfer_libraries_svr4,
|
|
linux_supports_agent,
|
|
#ifdef HAVE_LINUX_BTRACE
|
|
linux_supports_btrace,
|
|
linux_enable_btrace,
|
|
linux_low_disable_btrace,
|
|
linux_low_read_btrace,
|
|
linux_low_btrace_conf,
|
|
#else
|
|
NULL,
|
|
NULL,
|
|
NULL,
|
|
NULL,
|
|
NULL,
|
|
#endif
|
|
linux_supports_range_stepping,
|
|
linux_proc_pid_to_exec_file,
|
|
linux_mntns_open_cloexec,
|
|
linux_mntns_unlink,
|
|
linux_mntns_readlink,
|
|
linux_breakpoint_kind_from_pc,
|
|
linux_sw_breakpoint_from_kind,
|
|
linux_proc_tid_get_name,
|
|
linux_breakpoint_kind_from_current_state,
|
|
linux_supports_software_single_step,
|
|
linux_supports_catch_syscall,
|
|
linux_get_ipa_tdesc_idx,
|
|
#if USE_THREAD_DB
|
|
thread_db_thread_handle,
|
|
#else
|
|
NULL,
|
|
#endif
|
|
};
|
|
|
|
#ifdef HAVE_LINUX_REGSETS
|
|
void
|
|
initialize_regsets_info (struct regsets_info *info)
|
|
{
|
|
for (info->num_regsets = 0;
|
|
info->regsets[info->num_regsets].size >= 0;
|
|
info->num_regsets++)
|
|
;
|
|
}
|
|
#endif
|
|
|
|
void
|
|
initialize_low (void)
|
|
{
|
|
struct sigaction sigchld_action;
|
|
|
|
memset (&sigchld_action, 0, sizeof (sigchld_action));
|
|
set_target_ops (&linux_target_ops);
|
|
|
|
linux_ptrace_init_warnings ();
|
|
|
|
sigchld_action.sa_handler = sigchld_handler;
|
|
sigemptyset (&sigchld_action.sa_mask);
|
|
sigchld_action.sa_flags = SA_RESTART;
|
|
sigaction (SIGCHLD, &sigchld_action, NULL);
|
|
|
|
initialize_low_arch ();
|
|
|
|
linux_check_ptrace_features ();
|
|
}
|