1051 lines
28 KiB
C
1051 lines
28 KiB
C
/* Low level interface for debugging UnixWare user-mode threads for
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GDB, the GNU debugger.
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Copyright 1999, 2000, 2001 Free Software Foundation, Inc.
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Written by Nick Duffek <nsd@cygnus.com>.
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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 2 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, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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/* Like many systems, UnixWare implements two classes of threads:
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kernel-mode threads, which are scheduled by the kernel; and
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user-mode threads, which are scheduled by a library. UnixWare
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calls these two classes lightweight processes (LWPs) and threads,
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respectively.
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This module deals with user-mode threads. It calls procfs_ops
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functions to deal with LWPs and processes and core_ops functions to
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deal with core files.
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As of this writing, the user-mode thread debugging interface is not
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documented beyond the comments in <thread.h>. The following
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description has been gleaned from experience and from information
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provided by SCO.
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libthread.so, against which all UnixWare user-mode thread programs
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link, provides a global thread_debug structure named _thr_debug.
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It has three fields:
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(1) thr_map is a pointer to a pointer to an element of a
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thread_map ring. A thread_map contains a single thread's id
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number, state, LWP pointer, recent register state, and other
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useful information.
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(2) thr_brk is a pointer to a stub function that libthread.so
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calls when it changes a thread's state, e.g. by creating it,
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switching it to an LWP, or causing it to exit.
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(3) thr_debug_on controls whether libthread.so calls thr_brk().
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Debuggers are able to track thread activity by setting a private
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breakpoint on thr_brk() and setting thr_debug_on to 1.
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thr_brk() receives two arguments:
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(1) a pointer to a thread_map describing the thread being
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changed; and
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(2) an enum thread_change specifying one of the following
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changes:
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invalid unknown
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thread_create thread has just been created
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thread_exit thread has just exited
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switch_begin thread will be switched to an LWP
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switch_complete thread has been switched to an LWP
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cancel_complete thread wasn't switched to an LWP
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thread_suspend thread has been thr_suspend()ed
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thread_suspend_pending thread will be thr_suspend()ed
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thread_continue thread has been thr_continue()d
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The thread_map argument to thr_brk() is NULL under the following
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circumstances:
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- The main thread is being acted upon. The main thread always
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has id 1, so its thread_map is easy to find by scanning through
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_thr_debug.thr_map.
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- A "switch_complete" change is occurring, which means that the
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thread specified in the most recent "switch_begin" change has
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moved to an LWP.
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- A "cancel_complete" change is occurring, which means that the
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thread specified in the most recent "switch_begin" change has
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not moved to an LWP after all.
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- A spurious "switch_begin" change is occurring after a
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"thread_exit" change.
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Between switch_begin and switch_complete or cancel_complete, the
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affected thread's LWP pointer is not reliable. It is possible that
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other parts of the thread's thread_map are also unreliable during
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that time. */
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#include "defs.h"
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#include "gdbthread.h"
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#include "target.h"
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#include "inferior.h"
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#include "regcache.h"
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#include <fcntl.h>
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/* <thread.h> includes <sys/priocntl.h>, which requires boolean_t from
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<sys/types.h>, which doesn't typedef boolean_t with gcc. */
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#define boolean_t int
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#include <thread.h>
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#undef boolean_t
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#include <synch.h> /* for UnixWare 2.x */
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/* Prototypes for supply_gregset etc. */
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#include "gregset.h"
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/* Whether to emit debugging output. */
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#define DEBUG 0
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/* Default debugging output file, overridden by envvar UWTHR_DEBUG. */
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#define DEBUG_FILE "/dev/tty"
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/* #if DEBUG, write string S to the debugging output channel. */
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#if !DEBUG
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# define DBG(fmt_and_args)
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# define DBG2(fmt_and_args)
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#else
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# define DBG(fmt_and_args) dbg fmt_and_args
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# define DBG2(fmt_and_args)
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#endif
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/* Back end to CALL_BASE() and TRY_BASE(): evaluate CALL, then convert
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inferior_pid to a composite thread/process id. */
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#define CALL_BASE_1(call) \
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do { \
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DBG2(("CALL_BASE(" #call ")")); \
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call; \
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do_cleanups (infpid_cleanup); \
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} while (0)
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/* If inferior_pid can be converted to a composite lwp/process id, do so,
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evaluate base_ops function CALL, and then convert inferior_pid back to a
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composite thread/process id.
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Otherwise, issue an error message and return nonlocally. */
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#define CALL_BASE(call) \
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do { \
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if (!lwp_infpid ()) \
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error ("uw-thread: no lwp"); \
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CALL_BASE_1 (call); \
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} while (0)
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/* Like CALL_BASE(), but instead of returning nonlocally on error, set
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*CALLED to whether the inferior_pid conversion was successful. */
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#define TRY_BASE(call, called) \
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do { \
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if ((*(called) = lwp_infpid ())) \
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CALL_BASE_1 (call); \
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} while (0)
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/* Information passed by thread_iter() to its callback parameter. */
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typedef struct {
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struct thread_map map;
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__lwp_desc_t lwp;
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CORE_ADDR mapp;
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} iter_t;
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/* Private thread data for the thread_info struct. */
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struct private_thread_info {
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int stable; /* 0 if libthread.so is modifying thread map */
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int thrid; /* thread id assigned by libthread.so */
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int lwpid; /* thread's lwp if .stable, 0 means no lwp */
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CORE_ADDR mapp; /* address of thread's map structure */
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};
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/* procfs.c's target-specific operations. */
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extern struct target_ops procfs_ops;
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/* Flag to prevent procfs.c from starting inferior processes. */
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extern int procfs_suppress_run;
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/* This module's target-specific operations. */
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static struct target_ops uw_thread_ops;
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/* Copy of the target over which uw_thread_ops is pushed. This is
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more convenient than a pointer to procfs_ops or core_ops, because
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they lack current_target's default callbacks. */
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static struct target_ops base_ops;
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/* Saved pointer to previous owner of target_new_objfile_hook. */
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static void (*target_new_objfile_chain)(struct objfile *);
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/* Whether we are debugging a user-space thread program. This isn't
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set until after libthread.so is loaded by the program being
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debugged.
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Except for module one-time intialization and where otherwise
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documented, no functions in this module get called when
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!uw_thread_active. */
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static int uw_thread_active;
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/* For efficiency, cache the addresses of libthread.so's _thr_debug
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structure, its thr_brk stub function, and the main thread's map. */
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static CORE_ADDR thr_debug_addr;
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static CORE_ADDR thr_brk_addr;
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static CORE_ADDR thr_map_main;
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/* Remember the thread most recently marked as switching. Necessary because
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libthread.so passes null map when calling stub with tc_*_complete. */
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static struct thread_info *switchto_thread;
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/* Cleanup chain for safely restoring inferior_pid after CALL_BASE. */
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static struct cleanup *infpid_cleanup;
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#if DEBUG
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/* Helper function for DBG() macro: if printf-style FMT is non-null, format it
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with args and display the result on the debugging output channel. */
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static void
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dbg (char *fmt, ...)
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{
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static int fd = -1, len;
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va_list args;
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char buf[1024];
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char *path;
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if (!fmt)
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return;
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if (fd < 0)
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{
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path = getenv ("UWTHR_DEBUG");
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if (!path)
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path = DEBUG_FILE;
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if ((fd = open (path, O_WRONLY | O_CREAT | O_TRUNC, 0664)) < 0)
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error ("can't open %s\n", path);
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}
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va_start (args, fmt);
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vsprintf (buf, fmt, args);
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va_end (args);
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len = strlen (buf);
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buf[len] = '\n';
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(void)write (fd, buf, len + 1);
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}
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#if 0
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/* Return a string representing composite PID's components. */
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static char *
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dbgpid (int pid)
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{
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static char *buf, buf1[80], buf2[80];
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if (!buf || buf == buf2)
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buf = buf1;
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else
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buf = buf2;
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if (pid <= 0)
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sprintf (buf, "%d", pid);
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else
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sprintf (buf, "%s %d/%d", ISTID (pid) ? "thr" : "lwp",
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TIDGET (pid), PIDGET (pid));
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return buf;
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}
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/* Return a string representing thread state CHANGE. */
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static char *
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dbgchange (enum thread_change change)
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{
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switch (change) {
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case tc_invalid: return "invalid";
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case tc_thread_create: return "thread_create";
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case tc_thread_exit: return "thread_exit";
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case tc_switch_begin: return "switch_begin";
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case tc_switch_complete: return "switch_complete";
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case tc_cancel_complete: return "cancel_complete";
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case tc_thread_suspend: return "thread_suspend";
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case tc_thread_suspend_pending: return "thread_suspend_pending";
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case tc_thread_continue: return "thread_continue";
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default: return "unknown";
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}
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}
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/* Return a string representing thread STATE. */
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static char *
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dbgstate (int state)
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{
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switch (state) {
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case TS_ONPROC: return "running";
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case TS_SLEEP: return "sleeping";
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case TS_RUNNABLE: return "runnable";
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case TS_ZOMBIE: return "zombie";
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case TS_SUSPENDED: return "suspended";
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#ifdef TS_FORK
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case TS_FORK: return "forking";
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#endif
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default: return "confused";
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}
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}
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#endif /* 0 */
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#endif /* DEBUG */
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/* Read the contents of _thr_debug into *DEBUGP. Return success. */
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static int
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read_thr_debug (struct thread_debug *debugp)
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{
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return base_ops.to_xfer_memory (thr_debug_addr, (char *)debugp,
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sizeof (*debugp), 0, &base_ops);
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}
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/* Read into MAP the contents of the thread map at inferior process address
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MAPP. Return success. */
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static int
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read_map (CORE_ADDR mapp, struct thread_map *map)
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{
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return base_ops.to_xfer_memory ((CORE_ADDR)THR_MAP (mapp), (char *)map,
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sizeof (*map), 0, &base_ops);
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}
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/* Read into LWP the contents of the lwp decriptor at inferior process address
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LWPP. Return success. */
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static int
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read_lwp (CORE_ADDR lwpp, __lwp_desc_t *lwp)
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{
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return base_ops.to_xfer_memory (lwpp, (char *)lwp,
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sizeof (*lwp), 0, &base_ops);
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}
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/* Iterate through all user threads, applying FUNC(<map>, <lwp>, DATA) until
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(a) FUNC returns nonzero,
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(b) FUNC has been applied to all threads, or
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(c) an error occurs,
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where <map> is the thread's struct thread_map and <lwp> if non-null is the
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thread's current __lwp_desc_t.
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If a call to FUNC returns nonzero, return that value; otherwise, return 0. */
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static int
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thread_iter (int (*func)(iter_t *, void *), void *data)
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{
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struct thread_debug debug;
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CORE_ADDR first, mapp;
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iter_t iter;
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int ret;
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if (!read_thr_debug (&debug))
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return 0;
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if (!base_ops.to_xfer_memory ((CORE_ADDR)debug.thr_map, (char *)&mapp,
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sizeof (mapp), 0, &base_ops))
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return 0;
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if (!mapp)
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return 0;
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for (first = mapp;;)
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{
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if (!read_map (mapp, &iter.map))
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return 0;
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if (iter.map.thr_lwpp)
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if (!read_lwp ((CORE_ADDR)iter.map.thr_lwpp, &iter.lwp))
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return 0;
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iter.mapp = mapp;
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if ((ret = func (&iter, data)))
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return ret;
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mapp = (CORE_ADDR)iter.map.thr_next;
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if (mapp == first)
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return 0;
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}
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}
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/* Deactivate user-mode thread support. */
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static void
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deactivate_uw_thread (void)
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{
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remove_thread_event_breakpoints ();
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uw_thread_active = 0;
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unpush_target (&uw_thread_ops);
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}
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/* Return the composite lwp/process id corresponding to composite
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id PID. If PID is a thread with no lwp, return 0. */
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static int
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thr_to_lwp (int pid)
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{
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struct thread_info *info;
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int lid;
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if (!ISTID (pid))
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lid = pid;
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else if (!(info = find_thread_pid (pid)))
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lid = 0;
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else if (!info->private->lwpid)
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lid = 0;
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else
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lid = MKLID (pid, info->private->lwpid);
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DBG2((" thr_to_lwp(%s) = %s", dbgpid (pid), dbgpid (lid)));
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return lid;
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}
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/* find_thread_lwp() callback: return whether TP describes a thread
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associated with lwp id DATA. */
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static int
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find_thread_lwp_callback (struct thread_info *tp, void *data)
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{
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int lwpid = (int)data;
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if (!ISTID (tp->pid))
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return 0;
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if (!tp->private->stable)
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return 0;
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if (lwpid != tp->private->lwpid)
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return 0;
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/* match */
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return 1;
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}
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/* If a thread is associated with lwp id LWPID, return the corresponding
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member of the global thread list; otherwise, return null. */
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static struct thread_info *
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find_thread_lwp (int lwpid)
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{
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return iterate_over_threads (find_thread_lwp_callback, (void *)lwpid);
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}
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/* Return the composite thread/process id corresponding to composite
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id PID. If PID is an lwp with no thread, return PID. */
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static int
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lwp_to_thr (int pid)
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{
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struct thread_info *info;
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int tid = pid, lwpid;
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|
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if (ISTID (pid))
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goto done;
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if (!(lwpid = LIDGET (pid)))
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goto done;
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if (!(info = find_thread_lwp (lwpid)))
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goto done;
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tid = MKTID (pid, info->private->thrid);
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done:
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DBG2((ISTID (tid) ? NULL : "lwp_to_thr: no thr for %s", dbgpid (pid)));
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return tid;
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}
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|
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/* do_cleanups() callback: convert inferior_pid to a composite
|
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thread/process id after having made a procfs call. */
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|
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static void
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thr_infpid (void *unused)
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{
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int pid = lwp_to_thr (inferior_pid);
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DBG2((" inferior_pid from procfs: %s => %s",
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dbgpid (inferior_pid), dbgpid (pid)));
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inferior_pid = pid;
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}
|
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|
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/* If possible, convert inferior_pid to a composite lwp/process id in
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preparation for making a procfs call. Return success. */
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|
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static int
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lwp_infpid (void)
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{
|
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int pid = thr_to_lwp (inferior_pid);
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DBG2((" inferior_pid to procfs: %s => %s",
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dbgpid (inferior_pid), dbgpid (pid)));
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|
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if (!pid)
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return 0;
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|
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inferior_pid = pid;
|
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infpid_cleanup = make_cleanup (thr_infpid, NULL);
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return 1;
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}
|
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|
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/* Add to the global thread list a new user-mode thread with system id THRID,
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lwp id LWPID, map address MAPP, and composite thread/process PID. */
|
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|
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static void
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add_thread_uw (int thrid, int lwpid, CORE_ADDR mapp, int pid)
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{
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struct thread_info *newthread;
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|
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if ((newthread = add_thread (pid)) == NULL)
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error ("failed to create new thread structure");
|
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newthread->private = xmalloc (sizeof (struct private_thread_info));
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newthread->private->stable = 1;
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newthread->private->thrid = thrid;
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newthread->private->lwpid = lwpid;
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newthread->private->mapp = mapp;
|
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|
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if (target_has_execution)
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printf_unfiltered ("[New %s]\n", target_pid_to_str (pid));
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}
|
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|
|
/* notice_threads() and find_main() callback: if the thread list doesn't
|
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already contain the thread described by ITER, add it if it's the main
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thread or if !DATA. */
|
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|
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static int
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notice_thread (iter_t *iter, void *data)
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{
|
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int thrid = iter->map.thr_tid;
|
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int lwpid = !iter->map.thr_lwpp ? 0 : iter->lwp.lwp_id;
|
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int pid = MKTID (inferior_pid, thrid);
|
|
|
|
if (!find_thread_pid (pid) && (!data || thrid == 1))
|
|
add_thread_uw (thrid, lwpid, iter->mapp, pid);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Add to the thread list any threads it doesn't already contain. */
|
|
|
|
static void
|
|
notice_threads (void)
|
|
{
|
|
thread_iter (notice_thread, NULL);
|
|
}
|
|
|
|
/* Return the address of the main thread's map. On error, return 0. */
|
|
|
|
static CORE_ADDR
|
|
find_main (void)
|
|
{
|
|
if (!thr_map_main)
|
|
{
|
|
struct thread_info *info;
|
|
thread_iter (notice_thread, (void *)1);
|
|
if ((info = find_thread_pid (MKTID (inferior_pid, 1))))
|
|
thr_map_main = info->private->mapp;
|
|
}
|
|
return thr_map_main;
|
|
}
|
|
|
|
/* Attach to process specified by ARGS, then initialize for debugging it
|
|
and wait for the trace-trap that results from attaching.
|
|
|
|
This function only gets called with uw_thread_active == 0. */
|
|
|
|
static void
|
|
uw_thread_attach (char *args, int from_tty)
|
|
{
|
|
procfs_ops.to_attach (args, from_tty);
|
|
if (uw_thread_active)
|
|
thr_infpid (NULL);
|
|
}
|
|
|
|
/* Detach from the process attached to by uw_thread_attach(). */
|
|
|
|
static void
|
|
uw_thread_detach (char *args, int from_tty)
|
|
{
|
|
deactivate_uw_thread ();
|
|
base_ops.to_detach (args, from_tty);
|
|
}
|
|
|
|
/* Tell the inferior process to continue running thread PID if >= 0
|
|
and all threads otherwise. */
|
|
|
|
static void
|
|
uw_thread_resume (int pid, int step, enum target_signal signo)
|
|
{
|
|
if (pid > 0 && !(pid = thr_to_lwp (pid)))
|
|
pid = -1;
|
|
|
|
CALL_BASE (base_ops.to_resume (pid, step, signo));
|
|
}
|
|
|
|
/* If the trap we just received from lwp PID was due to a breakpoint
|
|
on the libthread.so debugging stub, update this module's state
|
|
accordingly. */
|
|
|
|
static void
|
|
libthread_stub (int pid)
|
|
{
|
|
CORE_ADDR sp, mapp, mapp_main;
|
|
enum thread_change change;
|
|
struct thread_map map;
|
|
__lwp_desc_t lwp;
|
|
int tid = 0, lwpid;
|
|
struct thread_info *info;
|
|
|
|
/* Check for stub breakpoint. */
|
|
if (read_pc_pid (pid) - DECR_PC_AFTER_BREAK != thr_brk_addr)
|
|
return;
|
|
|
|
/* Retrieve stub args. */
|
|
sp = read_register_pid (SP_REGNUM, pid);
|
|
if (!base_ops.to_xfer_memory (sp + SP_ARG0, (char *)&mapp,
|
|
sizeof (mapp), 0, &base_ops))
|
|
goto err;
|
|
if (!base_ops.to_xfer_memory (sp + SP_ARG0 + sizeof (mapp), (char *)&change,
|
|
sizeof (change), 0, &base_ops))
|
|
goto err;
|
|
|
|
/* create_inferior() may not have finished yet, so notice the main
|
|
thread to ensure that it's displayed first by add_thread(). */
|
|
mapp_main = find_main ();
|
|
|
|
/* Notice thread creation, deletion, or stability change. */
|
|
switch (change) {
|
|
case tc_switch_begin:
|
|
if (!mapp) /* usually means main thread */
|
|
mapp = mapp_main;
|
|
/* fall through */
|
|
|
|
case tc_thread_create:
|
|
case tc_thread_exit:
|
|
if (!mapp)
|
|
break;
|
|
if (!read_map (mapp, &map))
|
|
goto err;
|
|
tid = MKTID (pid, map.thr_tid);
|
|
|
|
switch (change) {
|
|
case tc_thread_create: /* new thread */
|
|
if (!map.thr_lwpp)
|
|
lwpid = 0;
|
|
else if (!read_lwp ((CORE_ADDR)map.thr_lwpp, &lwp))
|
|
goto err;
|
|
else
|
|
lwpid = lwp.lwp_id;
|
|
add_thread_uw (map.thr_tid, lwpid, mapp, tid);
|
|
break;
|
|
|
|
case tc_thread_exit: /* thread has exited */
|
|
printf_unfiltered ("[Exited %s]\n", target_pid_to_str (tid));
|
|
delete_thread (tid);
|
|
if (tid == inferior_pid)
|
|
inferior_pid = pid;
|
|
break;
|
|
|
|
case tc_switch_begin: /* lwp is switching threads */
|
|
if (switchto_thread)
|
|
goto err;
|
|
if (!(switchto_thread = find_thread_pid (tid)))
|
|
goto err;
|
|
switchto_thread->private->stable = 0;
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case tc_switch_complete: /* lwp has switched threads */
|
|
case tc_cancel_complete: /* lwp didn't switch threads */
|
|
if (!switchto_thread)
|
|
goto err;
|
|
|
|
if (change == tc_switch_complete)
|
|
{
|
|
/* If switchto_thread is the main thread, then (a) the corresponding
|
|
tc_switch_begin probably received a null map argument and therefore
|
|
(b) it may have been a spurious switch following a tc_thread_exit.
|
|
|
|
Therefore, explicitly query the thread's lwp before caching it in
|
|
its thread list entry. */
|
|
|
|
if (!read_map (switchto_thread->private->mapp, &map))
|
|
goto err;
|
|
if (map.thr_lwpp)
|
|
{
|
|
if (!read_lwp ((CORE_ADDR)map.thr_lwpp, &lwp))
|
|
goto err;
|
|
if ((info = find_thread_lwp (lwp.lwp_id)))
|
|
info->private->lwpid = 0;
|
|
switchto_thread->private->lwpid = lwp.lwp_id;
|
|
}
|
|
}
|
|
|
|
switchto_thread->private->stable = 1;
|
|
switchto_thread = NULL;
|
|
break;
|
|
|
|
case tc_invalid:
|
|
case tc_thread_suspend:
|
|
case tc_thread_suspend_pending:
|
|
case tc_thread_continue:
|
|
err:
|
|
DBG(("unexpected condition in libthread_stub()"));
|
|
break;
|
|
}
|
|
|
|
DBG2(("libthread_stub(%s): %s %s %s", dbgpid (pid), dbgpid (tid),
|
|
dbgchange (change), tid ? dbgstate (map.thr_state) : ""));
|
|
}
|
|
|
|
/* Wait for thread/lwp/process ID if >= 0 or for any thread otherwise. */
|
|
|
|
static int
|
|
uw_thread_wait (int pid, struct target_waitstatus *status)
|
|
{
|
|
if (pid > 0)
|
|
pid = thr_to_lwp (pid);
|
|
CALL_BASE (pid = base_ops.to_wait (pid > 0 ? pid : -1, status));
|
|
|
|
if (status->kind == TARGET_WAITKIND_STOPPED &&
|
|
status->value.sig == TARGET_SIGNAL_TRAP)
|
|
libthread_stub (pid);
|
|
|
|
return lwp_to_thr (pid);
|
|
}
|
|
|
|
/* Tell gdb about the registers in the thread/lwp/process specified by
|
|
inferior_pid. */
|
|
|
|
static void
|
|
uw_thread_fetch_registers (int regno)
|
|
{
|
|
int called;
|
|
struct thread_info *info;
|
|
struct thread_map map;
|
|
|
|
TRY_BASE (base_ops.to_fetch_registers (regno), &called);
|
|
if (called)
|
|
return;
|
|
|
|
if (!(info = find_thread_pid (inferior_pid)))
|
|
return;
|
|
if (!read_map (info->private->mapp, &map))
|
|
return;
|
|
|
|
supply_gregset (&map.thr_ucontext.uc_mcontext.gregs);
|
|
supply_fpregset (&map.thr_ucontext.uc_mcontext.fpregs);
|
|
}
|
|
|
|
/* Store gdb's current view of the register set into the thread/lwp/process
|
|
specified by inferior_pid. */
|
|
|
|
static void
|
|
uw_thread_store_registers (int regno)
|
|
{
|
|
CALL_BASE (base_ops.to_store_registers (regno));
|
|
}
|
|
|
|
/* Prepare to modify the registers array. */
|
|
|
|
static void
|
|
uw_thread_prepare_to_store (void)
|
|
{
|
|
CALL_BASE (base_ops.to_prepare_to_store ());
|
|
}
|
|
|
|
/* Fork an inferior process and start debugging it.
|
|
|
|
This function only gets called with uw_thread_active == 0. */
|
|
|
|
static void
|
|
uw_thread_create_inferior (char *exec_file, char *allargs, char **env)
|
|
{
|
|
if (uw_thread_active)
|
|
deactivate_uw_thread ();
|
|
|
|
procfs_ops.to_create_inferior (exec_file, allargs, env);
|
|
if (uw_thread_active)
|
|
{
|
|
find_main ();
|
|
thr_infpid (NULL);
|
|
}
|
|
}
|
|
|
|
/* Kill and forget about the inferior process. */
|
|
|
|
static void
|
|
uw_thread_kill (void)
|
|
{
|
|
base_ops.to_kill ();
|
|
}
|
|
|
|
/* Clean up after the inferior exits. */
|
|
|
|
static void
|
|
uw_thread_mourn_inferior (void)
|
|
{
|
|
deactivate_uw_thread ();
|
|
base_ops.to_mourn_inferior ();
|
|
}
|
|
|
|
/* Return whether this module can attach to and run processes.
|
|
|
|
This function only gets called with uw_thread_active == 0. */
|
|
|
|
static int
|
|
uw_thread_can_run (void)
|
|
{
|
|
return procfs_suppress_run;
|
|
}
|
|
|
|
/* Return whether thread PID is still valid. */
|
|
|
|
static int
|
|
uw_thread_alive (int pid)
|
|
{
|
|
if (!ISTID (pid))
|
|
return base_ops.to_thread_alive (pid);
|
|
|
|
/* If it's in the thread list, it's valid, because otherwise
|
|
libthread_stub() would have deleted it. */
|
|
return in_thread_list (pid);
|
|
}
|
|
|
|
/* Add to the thread list any threads and lwps it doesn't already contain. */
|
|
|
|
static void
|
|
uw_thread_find_new_threads (void)
|
|
{
|
|
CALL_BASE (if (base_ops.to_find_new_threads)
|
|
base_ops.to_find_new_threads ());
|
|
notice_threads ();
|
|
}
|
|
|
|
/* Return a string for pretty-printing PID in "info threads" output.
|
|
This may be called by either procfs.c or by generic gdb. */
|
|
|
|
static char *
|
|
uw_thread_pid_to_str (int pid)
|
|
{
|
|
#define FMT "Thread %d"
|
|
static char buf[sizeof (FMT) + 3 * sizeof (pid)];
|
|
|
|
if (!ISTID (pid))
|
|
/* core_ops says "process foo", so call procfs_ops explicitly. */
|
|
return procfs_ops.to_pid_to_str (pid);
|
|
|
|
sprintf (buf, FMT, TIDGET (pid));
|
|
#undef FMT
|
|
return buf;
|
|
}
|
|
|
|
/* Return a string displaying INFO state information in "info threads"
|
|
output. */
|
|
|
|
static char *
|
|
uw_extra_thread_info (struct thread_info *info)
|
|
{
|
|
static char buf[80];
|
|
struct thread_map map;
|
|
__lwp_desc_t lwp;
|
|
int lwpid;
|
|
char *name;
|
|
|
|
if (!ISTID (info->pid))
|
|
return NULL;
|
|
|
|
if (!info->private->stable)
|
|
return "switching";
|
|
|
|
if (!read_map (info->private->mapp, &map))
|
|
return NULL;
|
|
|
|
if (!map.thr_lwpp || !read_lwp ((CORE_ADDR)map.thr_lwpp, &lwp))
|
|
lwpid = 0;
|
|
else
|
|
lwpid = lwp.lwp_id;
|
|
|
|
switch (map.thr_state) {
|
|
case TS_ONPROC: name = "running"; break;
|
|
case TS_SLEEP: name = "sleeping"; break;
|
|
case TS_RUNNABLE: name = "runnable"; break;
|
|
case TS_ZOMBIE: name = "zombie"; break;
|
|
case TS_SUSPENDED: name = "suspended"; break;
|
|
#ifdef TS_FORK
|
|
case TS_FORK: name = "forking"; break;
|
|
#endif
|
|
default: name = "confused"; break;
|
|
}
|
|
|
|
if (!lwpid)
|
|
return name;
|
|
|
|
sprintf (buf, "%s, LWP %d", name, lwpid);
|
|
return buf;
|
|
}
|
|
|
|
/* Check whether libthread.so has just been loaded, and if so, try to
|
|
initialize user-space thread debugging support.
|
|
|
|
libthread.so loading happens while (a) an inferior process is being
|
|
started by procfs and (b) a core image is being loaded.
|
|
|
|
This function often gets called with uw_thread_active == 0. */
|
|
|
|
static void
|
|
libthread_init (void)
|
|
{
|
|
struct minimal_symbol *ms;
|
|
struct thread_debug debug;
|
|
CORE_ADDR onp;
|
|
struct breakpoint *b;
|
|
int one = 1;
|
|
|
|
/* Don't initialize twice. */
|
|
if (uw_thread_active)
|
|
return;
|
|
|
|
/* Check whether libthread.so has been loaded. */
|
|
if (!(ms = lookup_minimal_symbol ("_thr_debug", NULL, NULL)))
|
|
return;
|
|
|
|
/* Cache _thr_debug's address. */
|
|
if (!(thr_debug_addr = SYMBOL_VALUE_ADDRESS (ms)))
|
|
return;
|
|
|
|
/* Initialize base_ops.to_xfer_memory(). */
|
|
base_ops = current_target;
|
|
|
|
/* Load _thr_debug's current contents. */
|
|
if (!read_thr_debug (&debug))
|
|
return;
|
|
|
|
/* User code (e.g. my test programs) may dereference _thr_debug,
|
|
making it availble to GDB before shared libs are loaded. */
|
|
if (!debug.thr_map)
|
|
return;
|
|
|
|
/* libthread.so has been loaded, and the current_target should now
|
|
reflect core_ops or procfs_ops. */
|
|
push_target (&uw_thread_ops); /* must precede notice_threads() */
|
|
uw_thread_active = 1;
|
|
|
|
if (!target_has_execution)
|
|
|
|
/* Locate threads in core file. */
|
|
notice_threads ();
|
|
|
|
else
|
|
{
|
|
/* Set a breakpoint on the stub function provided by libthread.so. */
|
|
thr_brk_addr = (CORE_ADDR)debug.thr_brk;
|
|
if (!(b = create_thread_event_breakpoint (thr_brk_addr)))
|
|
goto err;
|
|
|
|
/* Activate the stub function. */
|
|
onp = (CORE_ADDR)&((struct thread_debug *)thr_debug_addr)->thr_debug_on;
|
|
if (!base_ops.to_xfer_memory ((CORE_ADDR)onp, (char *)&one,
|
|
sizeof (one), 1, &base_ops))
|
|
{
|
|
delete_breakpoint (b);
|
|
goto err;
|
|
}
|
|
|
|
/* Prepare for finding the main thread, which doesn't yet exist. */
|
|
thr_map_main = 0;
|
|
}
|
|
|
|
return;
|
|
|
|
err:
|
|
warning ("uw-thread: unable to initialize user-mode thread debugging\n");
|
|
deactivate_uw_thread ();
|
|
}
|
|
|
|
/* target_new_objfile_hook callback.
|
|
|
|
If OBJFILE is non-null, check whether libthread.so was just loaded,
|
|
and if so, prepare for user-mode thread debugging.
|
|
|
|
If OBJFILE is null, libthread.so has gone away, so stop debugging
|
|
user-mode threads.
|
|
|
|
This function often gets called with uw_thread_active == 0. */
|
|
|
|
static void
|
|
uw_thread_new_objfile (struct objfile *objfile)
|
|
{
|
|
if (objfile)
|
|
libthread_init ();
|
|
|
|
else if (uw_thread_active)
|
|
deactivate_uw_thread ();
|
|
|
|
if (target_new_objfile_chain)
|
|
target_new_objfile_chain (objfile);
|
|
}
|
|
|
|
/* Initialize uw_thread_ops. */
|
|
|
|
static void
|
|
init_uw_thread_ops (void)
|
|
{
|
|
uw_thread_ops.to_shortname = "unixware-threads";
|
|
uw_thread_ops.to_longname = "UnixWare threads and pthread.";
|
|
uw_thread_ops.to_doc = "UnixWare threads and pthread support.";
|
|
uw_thread_ops.to_attach = uw_thread_attach;
|
|
uw_thread_ops.to_detach = uw_thread_detach;
|
|
uw_thread_ops.to_resume = uw_thread_resume;
|
|
uw_thread_ops.to_wait = uw_thread_wait;
|
|
uw_thread_ops.to_fetch_registers = uw_thread_fetch_registers;
|
|
uw_thread_ops.to_store_registers = uw_thread_store_registers;
|
|
uw_thread_ops.to_prepare_to_store = uw_thread_prepare_to_store;
|
|
uw_thread_ops.to_create_inferior = uw_thread_create_inferior;
|
|
uw_thread_ops.to_kill = uw_thread_kill;
|
|
uw_thread_ops.to_mourn_inferior = uw_thread_mourn_inferior;
|
|
uw_thread_ops.to_can_run = uw_thread_can_run;
|
|
uw_thread_ops.to_thread_alive = uw_thread_alive;
|
|
uw_thread_ops.to_find_new_threads = uw_thread_find_new_threads;
|
|
uw_thread_ops.to_pid_to_str = uw_thread_pid_to_str;
|
|
uw_thread_ops.to_extra_thread_info = uw_extra_thread_info;
|
|
uw_thread_ops.to_stratum = thread_stratum;
|
|
uw_thread_ops.to_magic = OPS_MAGIC;
|
|
}
|
|
|
|
/* Module startup initialization function, automagically called by
|
|
init.c. */
|
|
|
|
void
|
|
_initialize_uw_thread (void)
|
|
{
|
|
init_uw_thread_ops ();
|
|
add_target (&uw_thread_ops);
|
|
|
|
procfs_suppress_run = 1;
|
|
|
|
/* Notice when libthread.so gets loaded. */
|
|
target_new_objfile_chain = target_new_objfile_hook;
|
|
target_new_objfile_hook = uw_thread_new_objfile;
|
|
}
|