844 lines
23 KiB
C
844 lines
23 KiB
C
/* Low-level child interface to ptrace.
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Copyright (C) 1988-2014 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 "defs.h"
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#include "command.h"
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#include "inferior.h"
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#include "inflow.h"
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#include "terminal.h"
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#include "gdbcore.h"
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#include "regcache.h"
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#include "gdb_assert.h"
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#include <string.h>
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#include "gdb_ptrace.h"
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#include "gdb_wait.h"
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#include <signal.h>
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#include "inf-ptrace.h"
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#include "inf-child.h"
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#include "gdbthread.h"
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#ifdef PT_GET_PROCESS_STATE
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static int
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inf_ptrace_follow_fork (struct target_ops *ops, int follow_child,
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int detach_fork)
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{
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pid_t pid, fpid;
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ptrace_state_t pe;
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pid = ptid_get_pid (inferior_ptid);
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if (ptrace (PT_GET_PROCESS_STATE, pid,
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(PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1)
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perror_with_name (("ptrace"));
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gdb_assert (pe.pe_report_event == PTRACE_FORK);
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fpid = pe.pe_other_pid;
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if (follow_child)
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{
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struct inferior *parent_inf, *child_inf;
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struct thread_info *tp;
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parent_inf = find_inferior_pid (pid);
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/* Add the child. */
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child_inf = add_inferior (fpid);
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child_inf->attach_flag = parent_inf->attach_flag;
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copy_terminal_info (child_inf, parent_inf);
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child_inf->pspace = parent_inf->pspace;
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child_inf->aspace = parent_inf->aspace;
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/* Before detaching from the parent, remove all breakpoints from
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it. */
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remove_breakpoints ();
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if (ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, 0) == -1)
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perror_with_name (("ptrace"));
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/* Switch inferior_ptid out of the parent's way. */
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inferior_ptid = pid_to_ptid (fpid);
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/* Delete the parent. */
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detach_inferior (pid);
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add_thread_silent (inferior_ptid);
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}
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else
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{
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/* Breakpoints have already been detached from the child by
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infrun.c. */
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if (ptrace (PT_DETACH, fpid, (PTRACE_TYPE_ARG3)1, 0) == -1)
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perror_with_name (("ptrace"));
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}
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return 0;
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}
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#endif /* PT_GET_PROCESS_STATE */
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/* Prepare to be traced. */
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static void
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inf_ptrace_me (void)
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{
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/* "Trace me, Dr. Memory!" */
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ptrace (PT_TRACE_ME, 0, (PTRACE_TYPE_ARG3)0, 0);
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}
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/* Start a new inferior Unix child process. EXEC_FILE is the file to
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run, ALLARGS is a string containing the arguments to the program.
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ENV is the environment vector to pass. If FROM_TTY is non-zero, be
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chatty about it. */
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static void
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inf_ptrace_create_inferior (struct target_ops *ops,
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char *exec_file, char *allargs, char **env,
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int from_tty)
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{
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int pid;
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/* Do not change either targets above or the same target if already present.
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The reason is the target stack is shared across multiple inferiors. */
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int ops_already_pushed = target_is_pushed (ops);
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struct cleanup *back_to = make_cleanup (null_cleanup, NULL);
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if (! ops_already_pushed)
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{
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/* Clear possible core file with its process_stratum. */
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push_target (ops);
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make_cleanup_unpush_target (ops);
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}
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pid = fork_inferior (exec_file, allargs, env, inf_ptrace_me, NULL,
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NULL, NULL, NULL);
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discard_cleanups (back_to);
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startup_inferior (START_INFERIOR_TRAPS_EXPECTED);
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/* On some targets, there must be some explicit actions taken after
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the inferior has been started up. */
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target_post_startup_inferior (pid_to_ptid (pid));
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}
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#ifdef PT_GET_PROCESS_STATE
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static void
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inf_ptrace_post_startup_inferior (ptid_t pid)
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{
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ptrace_event_t pe;
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/* Set the initial event mask. */
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memset (&pe, 0, sizeof pe);
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pe.pe_set_event |= PTRACE_FORK;
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if (ptrace (PT_SET_EVENT_MASK, ptid_get_pid (pid),
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(PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1)
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perror_with_name (("ptrace"));
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}
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#endif
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/* Clean up a rotting corpse of an inferior after it died. */
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static void
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inf_ptrace_mourn_inferior (struct target_ops *ops)
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{
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int status;
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/* Wait just one more time to collect the inferior's exit status.
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Do not check whether this succeeds though, since we may be
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dealing with a process that we attached to. Such a process will
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only report its exit status to its original parent. */
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waitpid (ptid_get_pid (inferior_ptid), &status, 0);
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generic_mourn_inferior ();
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if (!have_inferiors ())
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unpush_target (ops);
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}
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/* Attach to the process specified by ARGS. If FROM_TTY is non-zero,
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be chatty about it. */
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static void
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inf_ptrace_attach (struct target_ops *ops, char *args, int from_tty)
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{
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char *exec_file;
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pid_t pid;
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struct inferior *inf;
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/* Do not change either targets above or the same target if already present.
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The reason is the target stack is shared across multiple inferiors. */
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int ops_already_pushed = target_is_pushed (ops);
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struct cleanup *back_to = make_cleanup (null_cleanup, NULL);
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pid = parse_pid_to_attach (args);
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if (pid == getpid ()) /* Trying to masturbate? */
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error (_("I refuse to debug myself!"));
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if (! ops_already_pushed)
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{
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/* target_pid_to_str already uses the target. Also clear possible core
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file with its process_stratum. */
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push_target (ops);
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make_cleanup_unpush_target (ops);
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}
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if (from_tty)
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{
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exec_file = get_exec_file (0);
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if (exec_file)
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printf_unfiltered (_("Attaching to program: %s, %s\n"), exec_file,
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target_pid_to_str (pid_to_ptid (pid)));
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else
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printf_unfiltered (_("Attaching to %s\n"),
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target_pid_to_str (pid_to_ptid (pid)));
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gdb_flush (gdb_stdout);
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}
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#ifdef PT_ATTACH
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errno = 0;
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ptrace (PT_ATTACH, pid, (PTRACE_TYPE_ARG3)0, 0);
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if (errno != 0)
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perror_with_name (("ptrace"));
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#else
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error (_("This system does not support attaching to a process"));
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#endif
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inf = current_inferior ();
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inferior_appeared (inf, pid);
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inf->attach_flag = 1;
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inferior_ptid = pid_to_ptid (pid);
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/* Always add a main thread. If some target extends the ptrace
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target, it should decorate the ptid later with more info. */
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add_thread_silent (inferior_ptid);
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discard_cleanups (back_to);
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}
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#ifdef PT_GET_PROCESS_STATE
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static void
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inf_ptrace_post_attach (int pid)
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{
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ptrace_event_t pe;
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/* Set the initial event mask. */
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memset (&pe, 0, sizeof pe);
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pe.pe_set_event |= PTRACE_FORK;
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if (ptrace (PT_SET_EVENT_MASK, pid,
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(PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1)
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perror_with_name (("ptrace"));
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}
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#endif
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/* Detach from the inferior, optionally passing it the signal
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specified by ARGS. If FROM_TTY is non-zero, be chatty about it. */
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static void
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inf_ptrace_detach (struct target_ops *ops, const char *args, int from_tty)
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{
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pid_t pid = ptid_get_pid (inferior_ptid);
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int sig = 0;
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if (from_tty)
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{
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char *exec_file = get_exec_file (0);
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if (exec_file == 0)
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exec_file = "";
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printf_unfiltered (_("Detaching from program: %s, %s\n"), exec_file,
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target_pid_to_str (pid_to_ptid (pid)));
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gdb_flush (gdb_stdout);
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}
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if (args)
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sig = atoi (args);
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#ifdef PT_DETACH
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/* We'd better not have left any breakpoints in the program or it'll
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die when it hits one. Also note that this may only work if we
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previously attached to the inferior. It *might* work if we
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started the process ourselves. */
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errno = 0;
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ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, sig);
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if (errno != 0)
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perror_with_name (("ptrace"));
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#else
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error (_("This system does not support detaching from a process"));
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#endif
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inferior_ptid = null_ptid;
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detach_inferior (pid);
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if (!have_inferiors ())
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unpush_target (ops);
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}
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/* Kill the inferior. */
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static void
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inf_ptrace_kill (struct target_ops *ops)
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{
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pid_t pid = ptid_get_pid (inferior_ptid);
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int status;
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if (pid == 0)
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return;
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ptrace (PT_KILL, pid, (PTRACE_TYPE_ARG3)0, 0);
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waitpid (pid, &status, 0);
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target_mourn_inferior ();
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}
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/* Stop the inferior. */
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static void
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inf_ptrace_stop (ptid_t ptid)
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{
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/* Send a SIGINT to the process group. This acts just like the user
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typed a ^C on the controlling terminal. Note that using a
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negative process number in kill() is a System V-ism. The proper
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BSD interface is killpg(). However, all modern BSDs support the
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System V interface too. */
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kill (-inferior_process_group (), SIGINT);
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}
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/* Resume execution of thread PTID, or all threads if PTID is -1. If
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STEP is nonzero, single-step it. If SIGNAL is nonzero, give it
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that signal. */
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static void
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inf_ptrace_resume (struct target_ops *ops,
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ptid_t ptid, int step, enum gdb_signal signal)
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{
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pid_t pid = ptid_get_pid (ptid);
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int request;
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if (pid == -1)
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/* Resume all threads. Traditionally ptrace() only supports
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single-threaded processes, so simply resume the inferior. */
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pid = ptid_get_pid (inferior_ptid);
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if (catch_syscall_enabled () > 0)
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request = PT_SYSCALL;
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else
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request = PT_CONTINUE;
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if (step)
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{
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/* If this system does not support PT_STEP, a higher level
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function will have called single_step() to transmute the step
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request into a continue request (by setting breakpoints on
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all possible successor instructions), so we don't have to
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worry about that here. */
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request = PT_STEP;
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}
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/* An address of (PTRACE_TYPE_ARG3)1 tells ptrace to continue from
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where it was. If GDB wanted it to start some other way, we have
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already written a new program counter value to the child. */
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errno = 0;
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ptrace (request, pid, (PTRACE_TYPE_ARG3)1, gdb_signal_to_host (signal));
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if (errno != 0)
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perror_with_name (("ptrace"));
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}
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/* Wait for the child specified by PTID to do something. Return the
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process ID of the child, or MINUS_ONE_PTID in case of error; store
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the status in *OURSTATUS. */
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static ptid_t
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inf_ptrace_wait (struct target_ops *ops,
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ptid_t ptid, struct target_waitstatus *ourstatus, int options)
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{
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pid_t pid;
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int status, save_errno;
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do
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{
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set_sigint_trap ();
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||
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do
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{
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pid = waitpid (ptid_get_pid (ptid), &status, 0);
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save_errno = errno;
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}
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while (pid == -1 && errno == EINTR);
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||
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clear_sigint_trap ();
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||
|
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if (pid == -1)
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{
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fprintf_unfiltered (gdb_stderr,
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_("Child process unexpectedly missing: %s.\n"),
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safe_strerror (save_errno));
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/* Claim it exited with unknown signal. */
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ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
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ourstatus->value.sig = GDB_SIGNAL_UNKNOWN;
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return inferior_ptid;
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}
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/* Ignore terminated detached child processes. */
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||
if (!WIFSTOPPED (status) && pid != ptid_get_pid (inferior_ptid))
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pid = -1;
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||
}
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while (pid == -1);
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#ifdef PT_GET_PROCESS_STATE
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||
if (WIFSTOPPED (status))
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{
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||
ptrace_state_t pe;
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||
pid_t fpid;
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|
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if (ptrace (PT_GET_PROCESS_STATE, pid,
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(PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1)
|
||
perror_with_name (("ptrace"));
|
||
|
||
switch (pe.pe_report_event)
|
||
{
|
||
case PTRACE_FORK:
|
||
ourstatus->kind = TARGET_WAITKIND_FORKED;
|
||
ourstatus->value.related_pid = pid_to_ptid (pe.pe_other_pid);
|
||
|
||
/* Make sure the other end of the fork is stopped too. */
|
||
fpid = waitpid (pe.pe_other_pid, &status, 0);
|
||
if (fpid == -1)
|
||
perror_with_name (("waitpid"));
|
||
|
||
if (ptrace (PT_GET_PROCESS_STATE, fpid,
|
||
(PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1)
|
||
perror_with_name (("ptrace"));
|
||
|
||
gdb_assert (pe.pe_report_event == PTRACE_FORK);
|
||
gdb_assert (pe.pe_other_pid == pid);
|
||
if (fpid == ptid_get_pid (inferior_ptid))
|
||
{
|
||
ourstatus->value.related_pid = pid_to_ptid (pe.pe_other_pid);
|
||
return pid_to_ptid (fpid);
|
||
}
|
||
|
||
return pid_to_ptid (pid);
|
||
}
|
||
}
|
||
#endif
|
||
|
||
store_waitstatus (ourstatus, status);
|
||
return pid_to_ptid (pid);
|
||
}
|
||
|
||
/* Attempt a transfer all LEN bytes starting at OFFSET between the
|
||
inferior's OBJECT:ANNEX space and GDB's READBUF/WRITEBUF buffer.
|
||
Return the number of bytes actually transferred. */
|
||
|
||
static LONGEST
|
||
inf_ptrace_xfer_partial (struct target_ops *ops, enum target_object object,
|
||
const char *annex, gdb_byte *readbuf,
|
||
const gdb_byte *writebuf,
|
||
ULONGEST offset, LONGEST len)
|
||
{
|
||
pid_t pid = ptid_get_pid (inferior_ptid);
|
||
|
||
switch (object)
|
||
{
|
||
case TARGET_OBJECT_MEMORY:
|
||
#ifdef PT_IO
|
||
/* OpenBSD 3.1, NetBSD 1.6 and FreeBSD 5.0 have a new PT_IO
|
||
request that promises to be much more efficient in reading
|
||
and writing data in the traced process's address space. */
|
||
{
|
||
struct ptrace_io_desc piod;
|
||
|
||
/* NOTE: We assume that there are no distinct address spaces
|
||
for instruction and data. However, on OpenBSD 3.9 and
|
||
later, PIOD_WRITE_D doesn't allow changing memory that's
|
||
mapped read-only. Since most code segments will be
|
||
read-only, using PIOD_WRITE_D will prevent us from
|
||
inserting breakpoints, so we use PIOD_WRITE_I instead. */
|
||
piod.piod_op = writebuf ? PIOD_WRITE_I : PIOD_READ_D;
|
||
piod.piod_addr = writebuf ? (void *) writebuf : readbuf;
|
||
piod.piod_offs = (void *) (long) offset;
|
||
piod.piod_len = len;
|
||
|
||
errno = 0;
|
||
if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0)
|
||
/* Return the actual number of bytes read or written. */
|
||
return piod.piod_len;
|
||
/* If the PT_IO request is somehow not supported, fallback on
|
||
using PT_WRITE_D/PT_READ_D. Otherwise we will return zero
|
||
to indicate failure. */
|
||
if (errno != EINVAL)
|
||
return 0;
|
||
}
|
||
#endif
|
||
{
|
||
union
|
||
{
|
||
PTRACE_TYPE_RET word;
|
||
gdb_byte byte[sizeof (PTRACE_TYPE_RET)];
|
||
} buffer;
|
||
ULONGEST rounded_offset;
|
||
LONGEST partial_len;
|
||
|
||
/* Round the start offset down to the next long word
|
||
boundary. */
|
||
rounded_offset = offset & -(ULONGEST) sizeof (PTRACE_TYPE_RET);
|
||
|
||
/* Since ptrace will transfer a single word starting at that
|
||
rounded_offset the partial_len needs to be adjusted down to
|
||
that (remember this function only does a single transfer).
|
||
Should the required length be even less, adjust it down
|
||
again. */
|
||
partial_len = (rounded_offset + sizeof (PTRACE_TYPE_RET)) - offset;
|
||
if (partial_len > len)
|
||
partial_len = len;
|
||
|
||
if (writebuf)
|
||
{
|
||
/* If OFFSET:PARTIAL_LEN is smaller than
|
||
ROUNDED_OFFSET:WORDSIZE then a read/modify write will
|
||
be needed. Read in the entire word. */
|
||
if (rounded_offset < offset
|
||
|| (offset + partial_len
|
||
< rounded_offset + sizeof (PTRACE_TYPE_RET)))
|
||
/* Need part of initial word -- fetch it. */
|
||
buffer.word = ptrace (PT_READ_I, pid,
|
||
(PTRACE_TYPE_ARG3)(uintptr_t)
|
||
rounded_offset, 0);
|
||
|
||
/* Copy data to be written over corresponding part of
|
||
buffer. */
|
||
memcpy (buffer.byte + (offset - rounded_offset),
|
||
writebuf, partial_len);
|
||
|
||
errno = 0;
|
||
ptrace (PT_WRITE_D, pid,
|
||
(PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset,
|
||
buffer.word);
|
||
if (errno)
|
||
{
|
||
/* Using the appropriate one (I or D) is necessary for
|
||
Gould NP1, at least. */
|
||
errno = 0;
|
||
ptrace (PT_WRITE_I, pid,
|
||
(PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset,
|
||
buffer.word);
|
||
if (errno)
|
||
return 0;
|
||
}
|
||
}
|
||
|
||
if (readbuf)
|
||
{
|
||
errno = 0;
|
||
buffer.word = ptrace (PT_READ_I, pid,
|
||
(PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset,
|
||
0);
|
||
if (errno)
|
||
return 0;
|
||
/* Copy appropriate bytes out of the buffer. */
|
||
memcpy (readbuf, buffer.byte + (offset - rounded_offset),
|
||
partial_len);
|
||
}
|
||
|
||
return partial_len;
|
||
}
|
||
|
||
case TARGET_OBJECT_UNWIND_TABLE:
|
||
return -1;
|
||
|
||
case TARGET_OBJECT_AUXV:
|
||
#if defined (PT_IO) && defined (PIOD_READ_AUXV)
|
||
/* OpenBSD 4.5 has a new PIOD_READ_AUXV operation for the PT_IO
|
||
request that allows us to read the auxilliary vector. Other
|
||
BSD's may follow if they feel the need to support PIE. */
|
||
{
|
||
struct ptrace_io_desc piod;
|
||
|
||
if (writebuf)
|
||
return -1;
|
||
piod.piod_op = PIOD_READ_AUXV;
|
||
piod.piod_addr = readbuf;
|
||
piod.piod_offs = (void *) (long) offset;
|
||
piod.piod_len = len;
|
||
|
||
errno = 0;
|
||
if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0)
|
||
/* Return the actual number of bytes read or written. */
|
||
return piod.piod_len;
|
||
}
|
||
#endif
|
||
return -1;
|
||
|
||
case TARGET_OBJECT_WCOOKIE:
|
||
return -1;
|
||
|
||
default:
|
||
return -1;
|
||
}
|
||
}
|
||
|
||
/* Return non-zero if the thread specified by PTID is alive. */
|
||
|
||
static int
|
||
inf_ptrace_thread_alive (struct target_ops *ops, ptid_t ptid)
|
||
{
|
||
/* ??? Is kill the right way to do this? */
|
||
return (kill (ptid_get_pid (ptid), 0) != -1);
|
||
}
|
||
|
||
/* Print status information about what we're accessing. */
|
||
|
||
static void
|
||
inf_ptrace_files_info (struct target_ops *ignore)
|
||
{
|
||
struct inferior *inf = current_inferior ();
|
||
|
||
printf_filtered (_("\tUsing the running image of %s %s.\n"),
|
||
inf->attach_flag ? "attached" : "child",
|
||
target_pid_to_str (inferior_ptid));
|
||
}
|
||
|
||
static char *
|
||
inf_ptrace_pid_to_str (struct target_ops *ops, ptid_t ptid)
|
||
{
|
||
return normal_pid_to_str (ptid);
|
||
}
|
||
|
||
#if defined (PT_IO) && defined (PIOD_READ_AUXV)
|
||
|
||
/* Read one auxv entry from *READPTR, not reading locations >= ENDPTR.
|
||
Return 0 if *READPTR is already at the end of the buffer.
|
||
Return -1 if there is insufficient buffer for a whole entry.
|
||
Return 1 if an entry was read into *TYPEP and *VALP. */
|
||
|
||
static int
|
||
inf_ptrace_auxv_parse (struct target_ops *ops, gdb_byte **readptr,
|
||
gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp)
|
||
{
|
||
struct type *int_type = builtin_type (target_gdbarch ())->builtin_int;
|
||
struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr;
|
||
const int sizeof_auxv_type = TYPE_LENGTH (int_type);
|
||
const int sizeof_auxv_val = TYPE_LENGTH (ptr_type);
|
||
enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ());
|
||
gdb_byte *ptr = *readptr;
|
||
|
||
if (endptr == ptr)
|
||
return 0;
|
||
|
||
if (endptr - ptr < 2 * sizeof_auxv_val)
|
||
return -1;
|
||
|
||
*typep = extract_unsigned_integer (ptr, sizeof_auxv_type, byte_order);
|
||
ptr += sizeof_auxv_val; /* Alignment. */
|
||
*valp = extract_unsigned_integer (ptr, sizeof_auxv_val, byte_order);
|
||
ptr += sizeof_auxv_val;
|
||
|
||
*readptr = ptr;
|
||
return 1;
|
||
}
|
||
|
||
#endif
|
||
|
||
/* Create a prototype ptrace target. The client can override it with
|
||
local methods. */
|
||
|
||
struct target_ops *
|
||
inf_ptrace_target (void)
|
||
{
|
||
struct target_ops *t = inf_child_target ();
|
||
|
||
t->to_attach = inf_ptrace_attach;
|
||
t->to_detach = inf_ptrace_detach;
|
||
t->to_resume = inf_ptrace_resume;
|
||
t->to_wait = inf_ptrace_wait;
|
||
t->to_files_info = inf_ptrace_files_info;
|
||
t->to_kill = inf_ptrace_kill;
|
||
t->to_create_inferior = inf_ptrace_create_inferior;
|
||
#ifdef PT_GET_PROCESS_STATE
|
||
t->to_follow_fork = inf_ptrace_follow_fork;
|
||
t->to_post_startup_inferior = inf_ptrace_post_startup_inferior;
|
||
t->to_post_attach = inf_ptrace_post_attach;
|
||
#endif
|
||
t->to_mourn_inferior = inf_ptrace_mourn_inferior;
|
||
t->to_thread_alive = inf_ptrace_thread_alive;
|
||
t->to_pid_to_str = inf_ptrace_pid_to_str;
|
||
t->to_stop = inf_ptrace_stop;
|
||
t->to_xfer_partial = inf_ptrace_xfer_partial;
|
||
#if defined (PT_IO) && defined (PIOD_READ_AUXV)
|
||
t->to_auxv_parse = inf_ptrace_auxv_parse;
|
||
#endif
|
||
|
||
return t;
|
||
}
|
||
|
||
|
||
/* Pointer to a function that returns the offset within the user area
|
||
where a particular register is stored. */
|
||
static CORE_ADDR (*inf_ptrace_register_u_offset)(struct gdbarch *, int, int);
|
||
|
||
/* Fetch register REGNUM from the inferior. */
|
||
|
||
static void
|
||
inf_ptrace_fetch_register (struct regcache *regcache, int regnum)
|
||
{
|
||
struct gdbarch *gdbarch = get_regcache_arch (regcache);
|
||
CORE_ADDR addr;
|
||
size_t size;
|
||
PTRACE_TYPE_RET *buf;
|
||
int pid, i;
|
||
|
||
/* This isn't really an address, but ptrace thinks of it as one. */
|
||
addr = inf_ptrace_register_u_offset (gdbarch, regnum, 0);
|
||
if (addr == (CORE_ADDR)-1
|
||
|| gdbarch_cannot_fetch_register (gdbarch, regnum))
|
||
{
|
||
regcache_raw_supply (regcache, regnum, NULL);
|
||
return;
|
||
}
|
||
|
||
/* Cater for systems like GNU/Linux, that implement threads as
|
||
separate processes. */
|
||
pid = ptid_get_lwp (inferior_ptid);
|
||
if (pid == 0)
|
||
pid = ptid_get_pid (inferior_ptid);
|
||
|
||
size = register_size (gdbarch, regnum);
|
||
gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0);
|
||
buf = alloca (size);
|
||
|
||
/* Read the register contents from the inferior a chunk at a time. */
|
||
for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++)
|
||
{
|
||
errno = 0;
|
||
buf[i] = ptrace (PT_READ_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, 0);
|
||
if (errno != 0)
|
||
error (_("Couldn't read register %s (#%d): %s."),
|
||
gdbarch_register_name (gdbarch, regnum),
|
||
regnum, safe_strerror (errno));
|
||
|
||
addr += sizeof (PTRACE_TYPE_RET);
|
||
}
|
||
regcache_raw_supply (regcache, regnum, buf);
|
||
}
|
||
|
||
/* Fetch register REGNUM from the inferior. If REGNUM is -1, do this
|
||
for all registers. */
|
||
|
||
static void
|
||
inf_ptrace_fetch_registers (struct target_ops *ops,
|
||
struct regcache *regcache, int regnum)
|
||
{
|
||
if (regnum == -1)
|
||
for (regnum = 0;
|
||
regnum < gdbarch_num_regs (get_regcache_arch (regcache));
|
||
regnum++)
|
||
inf_ptrace_fetch_register (regcache, regnum);
|
||
else
|
||
inf_ptrace_fetch_register (regcache, regnum);
|
||
}
|
||
|
||
/* Store register REGNUM into the inferior. */
|
||
|
||
static void
|
||
inf_ptrace_store_register (const struct regcache *regcache, int regnum)
|
||
{
|
||
struct gdbarch *gdbarch = get_regcache_arch (regcache);
|
||
CORE_ADDR addr;
|
||
size_t size;
|
||
PTRACE_TYPE_RET *buf;
|
||
int pid, i;
|
||
|
||
/* This isn't really an address, but ptrace thinks of it as one. */
|
||
addr = inf_ptrace_register_u_offset (gdbarch, regnum, 1);
|
||
if (addr == (CORE_ADDR)-1
|
||
|| gdbarch_cannot_store_register (gdbarch, regnum))
|
||
return;
|
||
|
||
/* Cater for systems like GNU/Linux, that implement threads as
|
||
separate processes. */
|
||
pid = ptid_get_lwp (inferior_ptid);
|
||
if (pid == 0)
|
||
pid = ptid_get_pid (inferior_ptid);
|
||
|
||
size = register_size (gdbarch, regnum);
|
||
gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0);
|
||
buf = alloca (size);
|
||
|
||
/* Write the register contents into the inferior a chunk at a time. */
|
||
regcache_raw_collect (regcache, regnum, buf);
|
||
for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++)
|
||
{
|
||
errno = 0;
|
||
ptrace (PT_WRITE_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, buf[i]);
|
||
if (errno != 0)
|
||
error (_("Couldn't write register %s (#%d): %s."),
|
||
gdbarch_register_name (gdbarch, regnum),
|
||
regnum, safe_strerror (errno));
|
||
|
||
addr += sizeof (PTRACE_TYPE_RET);
|
||
}
|
||
}
|
||
|
||
/* Store register REGNUM back into the inferior. If REGNUM is -1, do
|
||
this for all registers. */
|
||
|
||
static void
|
||
inf_ptrace_store_registers (struct target_ops *ops,
|
||
struct regcache *regcache, int regnum)
|
||
{
|
||
if (regnum == -1)
|
||
for (regnum = 0;
|
||
regnum < gdbarch_num_regs (get_regcache_arch (regcache));
|
||
regnum++)
|
||
inf_ptrace_store_register (regcache, regnum);
|
||
else
|
||
inf_ptrace_store_register (regcache, regnum);
|
||
}
|
||
|
||
/* Create a "traditional" ptrace target. REGISTER_U_OFFSET should be
|
||
a function returning the offset within the user area where a
|
||
particular register is stored. */
|
||
|
||
struct target_ops *
|
||
inf_ptrace_trad_target (CORE_ADDR (*register_u_offset)
|
||
(struct gdbarch *, int, int))
|
||
{
|
||
struct target_ops *t = inf_ptrace_target();
|
||
|
||
gdb_assert (register_u_offset);
|
||
inf_ptrace_register_u_offset = register_u_offset;
|
||
t->to_fetch_registers = inf_ptrace_fetch_registers;
|
||
t->to_store_registers = inf_ptrace_store_registers;
|
||
|
||
return t;
|
||
}
|