/* libthread_db assisted debugging support, generic parts.
- Copyright (C) 1999, 2000, 2001, 2003, 2004, 2005, 2006
+ Copyright (C) 1999, 2000, 2001, 2003, 2004, 2005, 2006, 2007
Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "regcache.h"
#include "solib-svr4.h"
#include "gdbcore.h"
+#include "observer.h"
#include "linux-nat.h"
+#include <signal.h>
+
#ifdef HAVE_GNU_LIBC_VERSION_H
#include <gnu/libc-version.h>
#endif
/* If we're running on GNU/Linux, we must explicitly attach to any new
threads. */
-/* FIXME: There is certainly some room for improvements:
- - Cache LWP ids.
- - Bypass libthread_db when fetching or storing registers for
- threads bound to a LWP. */
-
/* This module's target vector. */
static struct target_ops thread_db_ops;
/* The target vector that we call for things this module can't handle. */
static struct target_ops *target_beneath;
-/* Pointer to the next function on the objfile event chain. */
-static void (*target_new_objfile_chain) (struct objfile * objfile);
-
/* Non-zero if we're using this module's target vector. */
static int using_thread_db;
return "only part of register set was written/read";
case TD_NOXREGS:
return "X register set not available for this thread";
+#ifdef THREAD_DB_HAS_TD_NOTALLOC
+ case TD_NOTALLOC:
+ return "thread has not yet allocated TLS for given module";
+#endif
+#ifdef THREAD_DB_HAS_TD_VERSION
+ case TD_VERSION:
+ return "versions of libpthread and libthread_db do not match";
+#endif
+#ifdef THREAD_DB_HAS_TD_NOTLS
+ case TD_NOTLS:
+ return "there is no TLS segment in the given module";
+#endif
default:
snprintf (buf, sizeof (buf), "unknown thread_db error '%d'", err);
return buf;
}
}
\f
+/* Return 1 if any threads have been registered. There may be none if
+ the threading library is not fully initialized yet. */
+
+static int
+have_threads_callback (struct thread_info *thread, void *dummy)
+{
+ return 1;
+}
+
+static int
+have_threads (void)
+{
+ return iterate_over_threads (have_threads_callback, NULL) != NULL;
+}
+
/* A callback function for td_ta_thr_iter, which we use to map all
threads to LWPs.
td_event_addset (&events, TD_CREATE);
#ifdef HAVE_GNU_LIBC_VERSION_H
- /* FIXME: kettenis/2000-04-23: The event reporting facility is
- broken for TD_DEATH events in glibc 2.1.3, so don't enable it for
- now. */
+ /* The event reporting facility is broken for TD_DEATH events in
+ glibc 2.1.3, so don't enable it if we have glibc but a lower
+ version. */
libc_version = gnu_get_libc_version ();
if (sscanf (libc_version, "%d.%d", &libc_major, &libc_minor) == 2
&& (libc_major > 2 || (libc_major == 2 && libc_minor > 1)))
td_err_e err;
static int already_loaded;
+ /* Do nothing if we couldn't load libthread_db.so.1. */
+ if (td_ta_new_p == NULL)
+ return;
+
/* First time through, report that libthread_db was successfuly
loaded. Can't print this in in thread_db_load as, at that stage,
the interpreter and it's console haven't started. */
{
if (objfile != NULL)
check_for_thread_db ();
-
- if (target_new_objfile_chain)
- target_new_objfile_chain (objfile);
}
/* Attach to a new thread. This function is called when we receive a
check_thread_signals ();
+ if (ti_p->ti_state == TD_THR_UNKNOWN || ti_p->ti_state == TD_THR_ZOMBIE)
+ return; /* A zombie thread -- do not attach. */
+
+ /* Under GNU/Linux, we have to attach to each and every thread. */
+ if (lin_lwp_attach_lwp (BUILD_LWP (ti_p->ti_lid, GET_PID (ptid)), 0) < 0)
+ return;
+
/* Add the thread to GDB's thread list. */
tp = add_thread (ptid);
tp->private = xmalloc (sizeof (struct private_thread_info));
if (verbose)
printf_unfiltered (_("[New %s]\n"), target_pid_to_str (ptid));
- if (ti_p->ti_state == TD_THR_UNKNOWN || ti_p->ti_state == TD_THR_ZOMBIE)
- return; /* A zombie thread -- do not attach. */
-
- /* Under GNU/Linux, we have to attach to each and every thread. */
-#ifdef ATTACH_LWP
- ATTACH_LWP (BUILD_LWP (ti_p->ti_lid, GET_PID (ptid)), 0);
-#endif
-
/* Enable thread event reporting for this thread. */
err = td_thr_event_enable_p (th_p, 1);
if (err != TD_OK)
target_pid_to_str (ptid), thread_db_err_str (err));
}
-static void
-thread_db_attach (char *args, int from_tty)
-{
- target_beneath->to_attach (args, from_tty);
-
- /* Destroy thread info; it's no longer valid. */
- init_thread_list ();
-
- /* The child process is now the actual multi-threaded
- program. Snatch its process ID... */
- proc_handle.pid = GET_PID (inferior_ptid);
-
- /* ...and perform the remaining initialization steps. */
- enable_thread_event_reporting ();
- thread_db_find_new_threads ();
-}
-
static void
detach_thread (ptid_t ptid, int verbose)
{
disable_thread_event_reporting ();
/* There's no need to save & restore inferior_ptid here, since the
- inferior is supposed to be survive this function call. */
+ inferior is not supposed to survive this function call. */
inferior_ptid = lwp_from_thread (inferior_ptid);
- /* Forget about the child's process ID. We shouldn't need it
- anymore. */
- proc_handle.pid = 0;
-
target_beneath->to_detach (args, from_tty);
+
+ /* Should this be done by detach_command? */
+ target_mourn_inferior ();
}
static int
int loop = 0;
/* Bail out early if we're not at a thread event breakpoint. */
- stop_pc = read_pc_pid (ptid) - DECR_PC_AFTER_BREAK;
+ stop_pc = read_pc_pid (ptid) - gdbarch_decr_pc_after_break (current_gdbarch);
if (stop_pc != td_create_bp_addr && stop_pc != td_death_bp_addr)
return;
ptid = target_beneath->to_wait (ptid, ourstatus);
- if (proc_handle.pid == 0)
- /* The current child process isn't the actual multi-threaded
- program yet, so don't try to do any special thread-specific
- post-processing and bail out early. */
- return ptid;
-
if (ourstatus->kind == TARGET_WAITKIND_EXITED
|| ourstatus->kind == TARGET_WAITKIND_SIGNALLED)
return pid_to_ptid (-1);
return pid_to_ptid (GET_PID (ptid));
}
+ /* If we do not know about the main thread yet, this would be a good time to
+ find it. */
+ if (ourstatus->kind == TARGET_WAITKIND_STOPPED && !have_threads ())
+ thread_db_find_new_threads ();
+
if (ourstatus->kind == TARGET_WAITKIND_STOPPED
&& ourstatus->value.sig == TARGET_SIGNAL_TRAP)
/* Check for a thread event. */
check_event (ptid);
- if (!ptid_equal (trap_ptid, null_ptid))
- trap_ptid = thread_from_lwp (trap_ptid);
-
- /* Change the ptid back into the higher level PID + TID format.
- If the thread is dead and no longer on the thread list, we will
- get back a dead ptid. This can occur if the thread death event
- gets postponed by other simultaneous events. In such a case,
- we want to just ignore the event and continue on. */
- ptid = thread_from_lwp (ptid);
- if (GET_PID (ptid) == -1)
- ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
-
- return ptid;
-}
-
-static LONGEST
-thread_db_xfer_partial (struct target_ops *ops, enum target_object object,
- const char *annex, gdb_byte *readbuf,
- const gdb_byte *writebuf, ULONGEST offset, LONGEST len)
-{
- struct cleanup *old_chain = save_inferior_ptid ();
- LONGEST xfer;
-
- if (is_thread (inferior_ptid))
+ if (have_threads ())
{
- /* FIXME: This seems to be necessary to make sure breakpoints
- are removed. */
- if (!target_thread_alive (inferior_ptid))
- inferior_ptid = pid_to_ptid (GET_PID (inferior_ptid));
- else
- inferior_ptid = lwp_from_thread (inferior_ptid);
+ /* Change ptids back into the higher level PID + TID format. If
+ the thread is dead and no longer on the thread list, we will
+ get back a dead ptid. This can occur if the thread death
+ event gets postponed by other simultaneous events. In such a
+ case, we want to just ignore the event and continue on. */
+
+ if (!ptid_equal (trap_ptid, null_ptid))
+ trap_ptid = thread_from_lwp (trap_ptid);
+
+ ptid = thread_from_lwp (ptid);
+ if (GET_PID (ptid) == -1)
+ ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
}
- xfer = target_beneath->to_xfer_partial (ops, object, annex,
- readbuf, writebuf, offset, len);
-
- do_cleanups (old_chain);
- return xfer;
+ return ptid;
}
static void
target_beneath->to_kill ();
}
-static void
-thread_db_create_inferior (char *exec_file, char *allargs, char **env,
- int from_tty)
-{
- unpush_target (&thread_db_ops);
- using_thread_db = 0;
- target_beneath->to_create_inferior (exec_file, allargs, env, from_tty);
-}
-
-static void
-thread_db_post_startup_inferior (ptid_t ptid)
-{
- if (proc_handle.pid == 0)
- {
- /* The child process is now the actual multi-threaded
- program. Snatch its process ID... */
- proc_handle.pid = GET_PID (ptid);
-
- /* ...and perform the remaining initialization steps. */
- enable_thread_event_reporting ();
- thread_db_find_new_threads ();
- }
-}
-
static void
thread_db_mourn_inferior (void)
{
ptid = ptid_build (GET_PID (inferior_ptid), ti.ti_lid, ti.ti_tid);
+ if (ti.ti_tid == 0)
+ {
+ /* A thread ID of zero means that this is the main thread, but
+ glibc has not yet initialized thread-local storage and the
+ pthread library. We do not know what the thread's TID will
+ be yet. Just enable event reporting and otherwise ignore
+ it. */
+
+ err = td_thr_event_enable_p (th_p, 1);
+ if (err != TD_OK)
+ error (_("Cannot enable thread event reporting for %s: %s"),
+ target_pid_to_str (ptid), thread_db_err_str (err));
+
+ return 0;
+ }
+
if (!in_thread_list (ptid))
attach_thread (ptid, th_p, &ti, 1);
thread_info = find_thread_pid (ptid);
if (thread_info == NULL)
- snprintf (buf, sizeof (buf), "Thread %ld (LWP %ld) (Missing)",
+ snprintf (buf, sizeof (buf), "Thread 0x%lx (LWP %ld) (Missing)",
GET_THREAD (ptid), GET_LWP (ptid));
else
- snprintf (buf, sizeof (buf), "Thread %ld (LWP %ld)",
+ snprintf (buf, sizeof (buf), "Thread 0x%lx (LWP %ld)",
GET_THREAD (ptid), GET_LWP (ptid));
return buf;
return NULL;
}
+/* Return 1 if this thread has the same LWP as the passed PTID. */
+
+static int
+same_ptid_callback (struct thread_info *thread, void *arg)
+{
+ ptid_t *ptid_p = arg;
+
+ return GET_LWP (thread->ptid) == GET_LWP (*ptid_p);
+}
+
/* Get the address of the thread local variable in load module LM which
is stored at OFFSET within the thread local storage for thread PTID. */
CORE_ADDR lm,
CORE_ADDR offset)
{
+ /* If we have not discovered any threads yet, check now. */
+ if (!is_thread (ptid) && !have_threads ())
+ thread_db_find_new_threads ();
+
+ /* Try to find a matching thread if we still have the LWP ID instead
+ of the thread ID. */
+ if (!is_thread (ptid))
+ {
+ struct thread_info *thread;
+
+ thread = iterate_over_threads (same_ptid_callback, &ptid);
+ if (thread != NULL)
+ ptid = thread->ptid;
+ }
+
if (is_thread (ptid))
{
td_err_e err;
/* Get info about the thread. */
thread_info = find_thread_pid (ptid);
+ gdb_assert (thread_info);
thread_db_map_id2thr (thread_info, 1);
/* Finally, get the address of the variable. */
thread_db_ops.to_shortname = "multi-thread";
thread_db_ops.to_longname = "multi-threaded child process.";
thread_db_ops.to_doc = "Threads and pthreads support.";
- thread_db_ops.to_attach = thread_db_attach;
thread_db_ops.to_detach = thread_db_detach;
thread_db_ops.to_resume = thread_db_resume;
thread_db_ops.to_wait = thread_db_wait;
- thread_db_ops.to_xfer_partial = thread_db_xfer_partial;
thread_db_ops.to_kill = thread_db_kill;
- thread_db_ops.to_create_inferior = thread_db_create_inferior;
- thread_db_ops.to_post_startup_inferior = thread_db_post_startup_inferior;
thread_db_ops.to_mourn_inferior = thread_db_mourn_inferior;
thread_db_ops.to_find_new_threads = thread_db_find_new_threads;
thread_db_ops.to_pid_to_str = thread_db_pid_to_str;
add_target (&thread_db_ops);
/* Add ourselves to objfile event chain. */
- target_new_objfile_chain = deprecated_target_new_objfile_hook;
- deprecated_target_new_objfile_hook = thread_db_new_objfile;
+ observer_attach_new_objfile (thread_db_new_objfile);
}
}