/* libthread_db assisted debugging support, generic parts.
- Copyright (C) 1999-2001, 2003-2012 Free Software Foundation, Inc.
+ Copyright (C) 1999-2013 Free Software Foundation, Inc.
This file is part of GDB.
#include <dlfcn.h>
#include "gdb_proc_service.h"
#include "gdb_thread_db.h"
-
+#include "gdb_vecs.h"
#include "bfd.h"
#include "command.h"
#include "exceptions.h"
#include "linux-procfs.h"
#include "linux-osdata.h"
#include "auto-load.h"
+#include "cli/cli-utils.h"
#include <signal.h>
#include <ctype.h>
-#ifdef HAVE_GNU_LIBC_VERSION_H
-#include <gnu/libc-version.h>
-#endif
-
/* GNU/Linux libthread_db support.
libthread_db is a library, provided along with libpthread.so, which
/* If non-zero, print details of libthread_db processing. */
-static int libthread_db_debug;
+static unsigned int libthread_db_debug;
static void
show_libthread_db_debug (struct ui_file *file, int from_tty,
thread_ptid = ptid_build (info->pid, ti.ti_lid, 0);
inout->thread_info = find_thread_ptid (thread_ptid);
- /* In the case of a zombie thread, don't continue. We don't want to
- attach to it thinking it is a new thread. */
- if (ti.ti_state == TD_THR_UNKNOWN || ti.ti_state == TD_THR_ZOMBIE)
- return TD_THR_ZOMBIE;
-
if (inout->thread_info == NULL)
{
/* New thread. Attach to it now (why wait?). */
return 0;
}
\f
-/* Convert between user-level thread ids and LWP ids. */
+/* Fetch the user-level thread id of PTID. */
-static ptid_t
+static void
thread_from_lwp (ptid_t ptid)
{
td_thrhandle_t th;
error (_("Cannot find user-level thread for LWP %ld: %s"),
GET_LWP (ptid), thread_db_err_str (err));
- /* Fetch the thread info. If we get back TD_THR_ZOMBIE, then the
- event thread has already died. If another gdb interface has called
- thread_alive() previously, the thread won't be found on the thread list
- anymore. In that case, we don't want to process this ptid anymore
- to avoid the possibility of later treating it as a newly
- discovered thread id that we should add to the list. Thus,
- we return a -1 ptid which is also how the thread list marks a
- dead thread. */
+ /* Long-winded way of fetching the thread info. */
io.thread_db_info = info;
io.thread_info = NULL;
- if (thread_get_info_callback (&th, &io) == TD_THR_ZOMBIE
- && io.thread_info == NULL)
- return minus_one_ptid;
-
- gdb_assert (ptid_get_tid (ptid) == 0);
- return ptid;
+ thread_get_info_callback (&th, &io);
}
\f
/* Set up the breakpoint. */
gdb_assert (exec_bfd);
(*bp) = (gdbarch_convert_from_func_ptr_addr
- (target_gdbarch,
+ (target_gdbarch (),
/* Do proper sign extension for the target. */
(bfd_get_sign_extend_vma (exec_bfd) > 0
? (CORE_ADDR) (intptr_t) notify.u.bptaddr
: (CORE_ADDR) (uintptr_t) notify.u.bptaddr),
¤t_target));
- create_thread_event_breakpoint (target_gdbarch, *bp);
+ create_thread_event_breakpoint (target_gdbarch (), *bp);
return TD_OK;
}
+/* Verify inferior's '\0'-terminated symbol VER_SYMBOL starts with "%d.%d" and
+ return 1 if this version is lower (and not equal) to
+ VER_MAJOR_MIN.VER_MINOR_MIN. Return 0 in all other cases. */
+
+static int
+inferior_has_bug (const char *ver_symbol, int ver_major_min, int ver_minor_min)
+{
+ struct minimal_symbol *version_msym;
+ CORE_ADDR version_addr;
+ char *version;
+ int err, got, retval = 0;
+
+ version_msym = lookup_minimal_symbol (ver_symbol, NULL, NULL);
+ if (version_msym == NULL)
+ return 0;
+
+ version_addr = SYMBOL_VALUE_ADDRESS (version_msym);
+ got = target_read_string (version_addr, &version, 32, &err);
+ if (err == 0 && memchr (version, 0, got) == &version[got -1])
+ {
+ int major, minor;
+
+ retval = (sscanf (version, "%d.%d", &major, &minor) == 2
+ && (major < ver_major_min
+ || (major == ver_major_min && minor < ver_minor_min)));
+ }
+ xfree (version);
+
+ return retval;
+}
+
static void
enable_thread_event_reporting (void)
{
td_thr_events_t events;
td_err_e err;
-#ifdef HAVE_GNU_LIBC_VERSION_H
- const char *libc_version;
- int libc_major, libc_minor;
-#endif
struct thread_db_info *info;
info = get_thread_db_info (GET_PID (inferior_ptid));
td_event_emptyset (&events);
td_event_addset (&events, TD_CREATE);
-#ifdef HAVE_GNU_LIBC_VERSION_H
- /* 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)))
-#endif
+ /* There is a bug fixed between linuxthreads 2.1.3 and 2.2 by
+ commit 2e4581e4fba917f1779cd0a010a45698586c190a
+ * manager.c (pthread_exited): Correctly report event as TD_REAP
+ instead of TD_DEATH. Fix comments.
+ where event reporting facility is broken for TD_DEATH events,
+ so don't enable it if we have glibc but a lower version. */
+ if (!inferior_has_bug ("__linuxthreads_version", 2, 2))
td_event_addset (&events, TD_DEATH);
err = info->td_ta_set_event_p (info->thread_agent, &events);
}
}
-/* Same as thread_db_find_new_threads_1, but silently ignore errors. */
+/* Similar as thread_db_find_new_threads_1, but try to silently ignore errors
+ if appropriate.
-static void
+ Return 1 if the caller should abort libthread_db initialization. Return 0
+ otherwise. */
+
+static int
thread_db_find_new_threads_silently (ptid_t ptid)
{
volatile struct gdb_exception except;
thread_db_find_new_threads_2 (ptid, 1);
}
- if (except.reason < 0 && libthread_db_debug)
+ if (except.reason < 0)
{
- exception_fprintf (gdb_stderr, except,
- "Warning: thread_db_find_new_threads_silently: ");
+ if (libthread_db_debug)
+ exception_fprintf (gdb_stderr, except,
+ "Warning: thread_db_find_new_threads_silently: ");
+
+ /* There is a bug fixed between nptl 2.6.1 and 2.7 by
+ commit 7d9d8bd18906fdd17364f372b160d7ab896ce909
+ where calls to td_thr_get_info fail with TD_ERR for statically linked
+ executables if td_thr_get_info is called before glibc has initialized
+ itself.
+
+ If the nptl bug is NOT present in the inferior and still thread_db
+ reports an error return 1. It means the inferior has corrupted thread
+ list and GDB should fall back only to LWPs.
+
+ If the nptl bug is present in the inferior return 0 to silently ignore
+ such errors, and let gdb enumerate threads again later. In such case
+ GDB cannot properly display LWPs if the inferior thread list is
+ corrupted. For core files it does not apply, no 'later enumeration'
+ is possible. */
+
+ if (!target_has_execution || !inferior_has_bug ("nptl_version", 2, 7))
+ {
+ exception_fprintf (gdb_stderr, except,
+ _("Warning: couldn't activate thread debugging "
+ "using libthread_db: "));
+ return 1;
+ }
}
+ return 0;
}
/* Lookup a library in which given symbol resides.
info->td_thr_event_enable_p = dlsym (info->handle, "td_thr_event_enable");
info->td_thr_tls_get_addr_p = dlsym (info->handle, "td_thr_tls_get_addr");
+ if (thread_db_find_new_threads_silently (inferior_ptid) != 0)
+ {
+ /* Even if libthread_db initializes, if the thread list is
+ corrupted, we'd not manage to list any threads. Better reject this
+ thread_db, and fall back to at least listing LWPs. */
+ return 0;
+ }
+
printf_unfiltered (_("[Thread debugging using libthread_db enabled]\n"));
if (libthread_db_debug || *libthread_db_search_path)
if (target_has_execution)
enable_thread_event_reporting ();
- /* There appears to be a bug in glibc-2.3.6: calls to td_thr_get_info fail
- with TD_ERR for statically linked executables if td_thr_get_info is
- called before glibc has initialized itself. Silently ignore such
- errors, and let gdb enumerate threads again later. */
- thread_db_find_new_threads_silently (inferior_ptid);
-
return 1;
}
}
/* Subroutine of try_thread_db_load_from_pdir to simplify it.
- Try loading libthread_db from the same directory as OBJ.
+ Try loading libthread_db in directory(OBJ)/SUBDIR.
+ SUBDIR may be NULL. It may also be something like "../lib64".
The result is true for success. */
static int
-try_thread_db_load_from_pdir_1 (struct objfile *obj)
+try_thread_db_load_from_pdir_1 (struct objfile *obj, const char *subdir)
{
struct cleanup *cleanup;
char *path, *cp;
return 0;
}
- path = xmalloc (strlen (obj->name) + 1 + strlen (LIBTHREAD_DB_SO) + 1);
+ path = xmalloc (strlen (obj->name) + (subdir ? strlen (subdir) + 1 : 0)
+ + 1 + strlen (LIBTHREAD_DB_SO) + 1);
cleanup = make_cleanup (xfree, path);
strcpy (path, obj->name);
cp = strrchr (path, '/');
/* This should at minimum hit the first character. */
gdb_assert (cp != NULL);
- strcpy (cp + 1, LIBTHREAD_DB_SO);
+ cp[1] = '\0';
+ if (subdir != NULL)
+ {
+ strcat (cp, subdir);
+ strcat (cp, "/");
+ }
+ strcat (cp, LIBTHREAD_DB_SO);
if (!file_is_auto_load_safe (path, _("auto-load: Loading libthread-db "
"library \"%s\" from $pdir.\n"),
}
/* Handle $pdir in libthread-db-search-path.
- Look for libthread_db in the directory of libpthread.
+ Look for libthread_db in directory(libpthread)/SUBDIR.
+ SUBDIR may be NULL. It may also be something like "../lib64".
The result is true for success. */
static int
-try_thread_db_load_from_pdir (void)
+try_thread_db_load_from_pdir (const char *subdir)
{
struct objfile *obj;
ALL_OBJFILES (obj)
if (libpthread_name_p (obj->name))
{
- if (try_thread_db_load_from_pdir_1 (obj))
+ if (try_thread_db_load_from_pdir_1 (obj, subdir))
return 1;
/* We may have found the separate-debug-info version of
libpthread, and it may live in a directory without a matching
libthread_db. */
if (obj->separate_debug_objfile_backlink != NULL)
- return try_thread_db_load_from_pdir_1 (obj->separate_debug_objfile_backlink);
+ return try_thread_db_load_from_pdir_1 (obj->separate_debug_objfile_backlink,
+ subdir);
return 0;
}
static int
thread_db_load_search (void)
{
- const char *search_path = libthread_db_search_path;
- int rc = 0;
+ VEC (char_ptr) *dir_vec;
+ struct cleanup *cleanups;
+ char *this_dir;
+ int i, rc = 0;
- while (*search_path)
+ dir_vec = dirnames_to_char_ptr_vec (libthread_db_search_path);
+ cleanups = make_cleanup_free_char_ptr_vec (dir_vec);
+
+ for (i = 0; VEC_iterate (char_ptr, dir_vec, i, this_dir); ++i)
{
- const char *end = strchr (search_path, ':');
- const char *this_dir = search_path;
+ const int pdir_len = sizeof ("$pdir") - 1;
size_t this_dir_len;
- if (end)
- {
- this_dir_len = end - search_path;
- search_path += this_dir_len + 1;
- }
- else
- {
- this_dir_len = strlen (this_dir);
- search_path += this_dir_len;
- }
+ this_dir_len = strlen (this_dir);
- if (this_dir_len == sizeof ("$pdir") - 1
- && strncmp (this_dir, "$pdir", this_dir_len) == 0)
+ if (strncmp (this_dir, "$pdir", pdir_len) == 0
+ && (this_dir[pdir_len] == '\0'
+ || this_dir[pdir_len] == '/'))
{
- if (try_thread_db_load_from_pdir ())
+ char *subdir = NULL;
+ struct cleanup *free_subdir_cleanup
+ = make_cleanup (null_cleanup, NULL);
+
+ if (this_dir[pdir_len] == '/')
{
- rc = 1;
- break;
+ subdir = xmalloc (strlen (this_dir));
+ make_cleanup (xfree, subdir);
+ strcpy (subdir, this_dir + pdir_len + 1);
}
+ rc = try_thread_db_load_from_pdir (subdir);
+ do_cleanups (free_subdir_cleanup);
+ if (rc)
+ break;
}
- else if (this_dir_len == sizeof ("$sdir") - 1
- && strncmp (this_dir, "$sdir", this_dir_len) == 0)
+ else if (strcmp (this_dir, "$sdir") == 0)
{
if (try_thread_db_load_from_sdir ())
{
}
}
+ do_cleanups (cleanups);
if (libthread_db_debug)
printf_unfiltered (_("thread_db_load_search returning %d\n"), rc);
return rc;
{
if (sigismember (&mask, i))
{
- if (signal_stop_update (target_signal_from_host (i), 0))
+ if (signal_stop_update (gdb_signal_from_host (i), 0))
sigaddset (&thread_stop_set, i);
- if (signal_print_update (target_signal_from_host (i), 0))
+ if (signal_print_update (gdb_signal_from_host (i), 0))
sigaddset (&thread_print_set, i);
thread_signals = 1;
}
correctly. */
if (objfile != NULL
+ /* libpthread with separate debug info has its debug info file already
+ loaded (and notified without successful thread_db initialization)
+ the time observer_notify_new_objfile is called for the library itself.
+ Static executables have their separate debug info loaded already
+ before the inferior has started. */
+ && objfile->separate_debug_objfile_backlink == NULL
/* Only check for thread_db if we loaded libpthread,
or if this is the main symbol file.
We need to check OBJF_MAINLINE to handle the case of debugging
if (target_has_execution)
check_thread_signals ();
- if (ti_p->ti_state == TD_THR_UNKNOWN || ti_p->ti_state == TD_THR_ZOMBIE)
- return 0; /* A zombie thread -- do not attach. */
-
/* Under GNU/Linux, we have to attach to each and every thread. */
if (target_has_execution
&& tp == NULL)
gdb_assert (ti_p->ti_tid != 0);
private->th = *th_p;
private->tid = ti_p->ti_tid;
+ if (ti_p->ti_state == TD_THR_UNKNOWN || ti_p->ti_state == TD_THR_ZOMBIE)
+ private->dying = 1;
/* Add the thread to GDB's thread list. */
if (tp == NULL)
thread_db_find_new_threads_1 (ptid);
if (ourstatus->kind == TARGET_WAITKIND_STOPPED
- && ourstatus->value.sig == TARGET_SIGNAL_TRAP)
+ && ourstatus->value.sig == GDB_SIGNAL_TRAP)
/* Check for a thread event. */
check_event (ptid);
if (have_threads (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. */
-
- ptid = thread_from_lwp (ptid);
- if (GET_PID (ptid) == -1)
- ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
+ /* Fill in the thread's user-level thread id. */
+ thread_from_lwp (ptid);
}
return ptid;
error (_("find_new_threads_callback: cannot get thread info: %s"),
thread_db_err_str (err));
- if (ti.ti_state == TD_THR_UNKNOWN || ti.ti_state == TD_THR_ZOMBIE)
- return 0; /* A zombie -- ignore. */
-
if (ti.ti_tid == 0)
{
/* A thread ID of zero means that this is the main thread, but
static void
thread_db_find_new_threads_2 (ptid_t ptid, int until_no_new)
{
- td_err_e err;
+ td_err_e err = TD_OK;
struct thread_db_info *info;
- int pid = ptid_get_pid (ptid);
int i, loop;
info = get_thread_db_info (GET_PID (ptid));
The 4 is a heuristic: there is an inherent race here, and I have
seen that 2 iterations in a row are not always sufficient to
"capture" all threads. */
- for (i = 0, loop = 0; loop < 4; ++i, ++loop)
- if (find_new_threads_once (info, i, NULL) != 0)
- /* Found some new threads. Restart the loop from beginning. */
- loop = -1;
+ for (i = 0, loop = 0; loop < 4 && err == TD_OK; ++i, ++loop)
+ if (find_new_threads_once (info, i, &err) != 0)
+ {
+ /* Found some new threads. Restart the loop from beginning. */
+ loop = -1;
+ }
}
else
- {
- find_new_threads_once (info, 0, &err);
- if (err != TD_OK)
- error (_("Cannot find new threads: %s"), thread_db_err_str (err));
- }
+ find_new_threads_once (info, 0, &err);
+
+ if (err != TD_OK)
+ error (_("Cannot find new threads: %s"), thread_db_err_str (err));
}
static void
static void
thread_db_resume (struct target_ops *ops,
- ptid_t ptid, int step, enum target_signal signo)
+ ptid_t ptid, int step, enum gdb_signal signo)
{
struct target_ops *beneath = find_target_beneath (ops);
struct thread_db_info *info;
char *pids;
int i;
- while (isspace (*cs))
- cs++;
+ cs = skip_spaces_const (cs);
if (*cs)
error (_("'info auto-load libthread-db' does not accept any parameters"));
thread_db_ops.to_extra_thread_info = thread_db_extra_thread_info;
thread_db_ops.to_get_ada_task_ptid = thread_db_get_ada_task_ptid;
thread_db_ops.to_magic = OPS_MAGIC;
+
+ complete_target_initialization (&thread_db_ops);
}
/* Provide a prototype to silence -Wmissing-prototypes. */
_initialize_thread_db (void)
{
init_thread_db_ops ();
- add_target (&thread_db_ops);
/* Defer loading of libthread_db.so until inferior is running.
This allows gdb to load correct libthread_db for a given
NULL,
&setlist, &showlist);
- add_setshow_zinteger_cmd ("libthread-db", class_maintenance,
- &libthread_db_debug, _("\
+ add_setshow_zuinteger_cmd ("libthread-db", class_maintenance,
+ &libthread_db_debug, _("\
Set libthread-db debugging."), _("\
Show libthread-db debugging."), _("\
When non-zero, libthread-db debugging is enabled."),
- NULL,
- show_libthread_db_debug,
- &setdebuglist, &showdebuglist);
+ NULL,
+ show_libthread_db_debug,
+ &setdebuglist, &showdebuglist);
add_setshow_boolean_cmd ("libthread-db", class_support,
&auto_load_thread_db, _("\
projects / deliverable / binutils-gdb.git / blobdiff