/* libthread_db assisted debugging support, generic parts.
- Copyright (C) 1999-2015 Free Software Foundation, Inc.
+ Copyright (C) 1999-2018 Free Software Foundation, Inc.
This file is part of GDB.
#include "solib.h"
#include "solib-svr4.h"
#include "gdbcore.h"
-#include "observer.h"
+#include "observable.h"
#include "linux-nat.h"
#include "nat/linux-procfs.h"
#include "nat/linux-ptrace.h"
#include <signal.h>
#include <ctype.h>
#include "nat/linux-namespaces.h"
+#include <algorithm>
+#include "common/pathstuff.h"
/* GNU/Linux libthread_db support.
created, thread IDs (usually, the result of pthread_self), and
thread-local variables.
- The libthread_db interface originates on Solaris, where it is
- both more powerful and more complicated. This implementation
- only works for LinuxThreads and NPTL, the two glibc threading
- libraries. It assumes that each thread is permanently assigned
- to a single light-weight process (LWP).
+ The libthread_db interface originates on Solaris, where it is both
+ more powerful and more complicated. This implementation only works
+ for NPTL, the glibc threading library. It assumes that each thread
+ is permanently assigned to a single light-weight process (LWP). At
+ some point it also supported the older LinuxThreads library, but it
+ no longer does.
libthread_db-specific information is stored in the "private" field
of struct thread_info. When the field is NULL we do not yet have
by the "set auto-load libthread-db" command. */
static int auto_load_thread_db = 1;
-/* Returns true if we need to use thread_db thread create/death event
- breakpoints to learn about threads. */
-
-static int
-thread_db_use_events (void)
-{
- /* Not necessary if the kernel supports clone events. */
- return !linux_supports_traceclone ();
-}
-
/* "show" command for the auto_load_thread_db configuration variable. */
static void
}
static void
-set_libthread_db_search_path (char *ignored, int from_tty,
+set_libthread_db_search_path (const char *ignored, int from_tty,
struct cmd_list_element *c)
{
if (*libthread_db_search_path == '\0')
be able to ignore such stale entries. */
int need_stale_parent_threads_check;
- /* Location of the thread creation event breakpoint. The code at
- this location in the child process will be called by the pthread
- library whenever a new thread is created. By setting a special
- breakpoint at this location, GDB can detect when a new thread is
- created. We obtain this location via the td_ta_event_addr
- call. */
- CORE_ADDR td_create_bp_addr;
-
- /* Location of the thread death event breakpoint. */
- CORE_ADDR td_death_bp_addr;
-
/* Pointers to the libthread_db functions. */
td_init_ftype *td_init_p;
td_ta_new_ftype *td_ta_new_p;
td_ta_map_lwp2thr_ftype *td_ta_map_lwp2thr_p;
td_ta_thr_iter_ftype *td_ta_thr_iter_p;
- td_ta_event_addr_ftype *td_ta_event_addr_p;
- td_ta_set_event_ftype *td_ta_set_event_p;
- td_ta_clear_event_ftype *td_ta_clear_event_p;
- td_ta_event_getmsg_ftype * td_ta_event_getmsg_p;
- td_thr_validate_ftype *td_thr_validate_p;
td_thr_get_info_ftype *td_thr_get_info_p;
- td_thr_event_enable_ftype *td_thr_event_enable_p;
td_thr_tls_get_addr_ftype *td_thr_tls_get_addr_p;
td_thr_tlsbase_ftype *td_thr_tlsbase_p;
};
static void check_thread_signals (void);
-static void record_thread (struct thread_db_info *info,
- struct thread_info *tp,
- ptid_t ptid, const td_thrhandle_t *th_p,
- const td_thrinfo_t *ti_p);
+static struct thread_info *record_thread
+ (struct thread_db_info *info, struct thread_info *tp,
+ ptid_t ptid, const td_thrhandle_t *th_p, const td_thrinfo_t *ti_p);
/* Add the current inferior to the list of processes using libpthread.
Return a pointer to the newly allocated object that was added to
static struct thread_db_info *
add_thread_db_info (void *handle)
{
- struct thread_db_info *info;
+ struct thread_db_info *info = XCNEW (struct thread_db_info);
- info = xcalloc (1, sizeof (*info));
info->pid = ptid_get_pid (inferior_ptid);
info->handle = handle;
xfree (info);
}
-/* Prototypes for local functions. */
-static int attach_thread (ptid_t ptid, const td_thrhandle_t *th_p,
- const td_thrinfo_t *ti_p);
-static void detach_thread (ptid_t ptid);
-\f
-
/* Use "struct private_thread_info" to cache thread state. This is
a substantial optimization. */
-struct private_thread_info
+struct thread_db_thread_info : public private_thread_info
{
/* Flag set when we see a TD_DEATH event for this thread. */
- unsigned int dying:1;
+ bool dying = false;
/* Cached thread state. */
- td_thrhandle_t th;
- thread_t tid;
+ td_thrhandle_t th {};
+ thread_t tid {};
};
-\f
-static char *
+static thread_db_thread_info *
+get_thread_db_thread_info (thread_info *thread)
+{
+ return static_cast<thread_db_thread_info *> (thread->priv.get ());
+}
+
+static const char *
thread_db_err_str (td_err_e err)
{
static char buf[64];
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 *args)
-{
- int pid = * (int *) args;
-
- if (ptid_get_pid (thread->ptid) != pid)
- return 0;
-
- return thread->priv != NULL;
-}
-static int
-have_threads (ptid_t ptid)
-{
- int pid = ptid_get_pid (ptid);
-
- return iterate_over_threads (have_threads_callback, &pid) != NULL;
-}
-
-\f
/* Fetch the user-level thread id of PTID. */
-static void
+static struct thread_info *
thread_from_lwp (ptid_t ptid)
{
td_thrhandle_t th;
/* Fill the cache. */
tp = find_thread_ptid (ptid);
- record_thread (info, tp, ptid, &th, &ti);
+ return record_thread (info, tp, ptid, &th, &ti);
}
\f
int
thread_db_notice_clone (ptid_t parent, ptid_t child)
{
- td_thrhandle_t th;
- td_thrinfo_t ti;
- td_err_e err;
struct thread_db_info *info;
info = get_thread_db_info (ptid_get_pid (child));
return sym;
}
-static td_err_e
-enable_thread_event (td_event_e event, CORE_ADDR *bp)
-{
- td_notify_t notify;
- td_err_e err;
- struct thread_db_info *info;
-
- info = get_thread_db_info (ptid_get_pid (inferior_ptid));
-
- /* Access an lwp we know is stopped. */
- info->proc_handle.ptid = inferior_ptid;
-
- /* Get the breakpoint address for thread EVENT. */
- err = info->td_ta_event_addr_p (info->thread_agent, event, ¬ify);
- if (err != TD_OK)
- return err;
-
- /* Set up the breakpoint. */
- gdb_assert (exec_bfd);
- (*bp) = (gdbarch_convert_from_func_ptr_addr
- (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);
-
- 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. */
return retval;
}
-static void
-enable_thread_event_reporting (void)
-{
- td_thr_events_t events;
- td_err_e err;
- struct thread_db_info *info;
-
- info = get_thread_db_info (ptid_get_pid (inferior_ptid));
-
- /* We cannot use the thread event reporting facility if these
- functions aren't available. */
- if (info->td_ta_event_addr_p == NULL
- || info->td_ta_set_event_p == NULL
- || info->td_ta_event_getmsg_p == NULL
- || info->td_thr_event_enable_p == NULL)
- return;
-
- /* Set the process wide mask saying which events we're interested in. */
- td_event_emptyset (&events);
- td_event_addset (&events, TD_CREATE);
-
- /* 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);
- if (err != TD_OK)
- {
- warning (_("Unable to set global thread event mask: %s"),
- thread_db_err_str (err));
- return;
- }
-
- /* Delete previous thread event breakpoints, if any. */
- remove_thread_event_breakpoints ();
- info->td_create_bp_addr = 0;
- info->td_death_bp_addr = 0;
-
- /* Set up the thread creation event. */
- err = enable_thread_event (TD_CREATE, &info->td_create_bp_addr);
- if (err != TD_OK)
- {
- warning (_("Unable to get location for thread creation breakpoint: %s"),
- thread_db_err_str (err));
- return;
- }
-
- /* Set up the thread death event. */
- err = enable_thread_event (TD_DEATH, &info->td_death_bp_addr);
- if (err != TD_OK)
- {
- warning (_("Unable to get location for thread death breakpoint: %s"),
- thread_db_err_str (err));
- return;
- }
-}
-
/* Similar as thread_db_find_new_threads_1, but try to silently ignore errors
if appropriate.
/* These are essential. */
CHK (TDB_VERBOSE_DLSYM (info, td_ta_map_lwp2thr));
- CHK (TDB_VERBOSE_DLSYM (info, td_ta_thr_iter));
- CHK (TDB_VERBOSE_DLSYM (info, td_thr_validate));
CHK (TDB_VERBOSE_DLSYM (info, td_thr_get_info));
/* These are not essential. */
- TDB_DLSYM (info, td_ta_event_addr);
- TDB_DLSYM (info, td_ta_set_event);
- TDB_DLSYM (info, td_ta_clear_event);
- TDB_DLSYM (info, td_ta_event_getmsg);
- TDB_DLSYM (info, td_thr_event_enable);
TDB_DLSYM (info, td_thr_tls_get_addr);
TDB_DLSYM (info, td_thr_tlsbase);
-#undef TDB_VERBOSE_DLSYM
-#undef TDB_DLSYM
-#undef CHK
-
/* It's best to avoid td_ta_thr_iter if possible. That walks data
structures in the inferior's address space that may be corrupted,
or, if the target is running, may change while we walk them. If
currently on core targets, as it uses ptrace directly. */
if (target_has_execution
&& linux_proc_task_list_dir_exists (ptid_get_pid (inferior_ptid)))
+ info->td_ta_thr_iter_p = NULL;
+ else
+ CHK (TDB_VERBOSE_DLSYM (info, td_ta_thr_iter));
+
+#undef TDB_VERBOSE_DLSYM
+#undef TDB_DLSYM
+#undef CHK
+
+ if (info->td_ta_thr_iter_p == NULL)
{
struct lwp_info *lp;
int pid = ptid_get_pid (inferior_ptid);
struct ui_file *file;
const char *library;
- library = dladdr_to_soname (*info->td_ta_new_p);
+ library = dladdr_to_soname ((const void *) *info->td_ta_new_p);
if (library == NULL)
library = LIBTHREAD_DB_SO;
if (thread_db_list->next == NULL)
push_target (&thread_db_ops);
- /* Enable event reporting, but not when debugging a core file. */
- if (target_has_execution && thread_db_use_events ())
- enable_thread_event_reporting ();
-
return 1;
}
/* Do not save system library name, that one is always trusted. */
if (strchr (library, '/') != NULL)
- info->filename = gdb_realpath (library);
+ info->filename = gdb_realpath (library).release ();
if (try_thread_db_load_1 (info))
return 1;
static int
try_thread_db_load_from_pdir_1 (struct objfile *obj, const char *subdir)
{
- struct cleanup *cleanup;
- char *path, *cp;
- int result;
const char *obj_name = objfile_name (obj);
if (obj_name[0] != '/')
return 0;
}
- 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, '/');
+ std::string path = obj_name;
+ size_t cp = path.rfind ('/');
/* This should at minimum hit the first character. */
- gdb_assert (cp != NULL);
- cp[1] = '\0';
+ gdb_assert (cp != std::string::npos);
+ path.resize (cp + 1);
if (subdir != NULL)
- {
- strcat (cp, subdir);
- strcat (cp, "/");
- }
- strcat (cp, LIBTHREAD_DB_SO);
+ path = path + subdir + "/";
+ path += LIBTHREAD_DB_SO;
- result = try_thread_db_load (path, 1);
-
- do_cleanups (cleanup);
- return result;
+ return try_thread_db_load (path.c_str (), 1);
}
/* Handle $pdir in libthread-db-search-path.
static int
try_thread_db_load_from_dir (const char *dir, size_t dir_len)
{
- struct cleanup *cleanup;
- char *path;
- int result;
-
if (!auto_load_thread_db)
return 0;
- path = xmalloc (dir_len + 1 + strlen (LIBTHREAD_DB_SO) + 1);
- cleanup = make_cleanup (xfree, path);
+ std::string path = std::string (dir, dir_len) + "/" + LIBTHREAD_DB_SO;
- memcpy (path, dir, dir_len);
- path[dir_len] = '/';
- strcpy (path + dir_len + 1, LIBTHREAD_DB_SO);
-
- result = try_thread_db_load (path, 1);
-
- do_cleanups (cleanup);
- return result;
+ return try_thread_db_load (path.c_str (), 1);
}
/* Search libthread_db_search_path for libthread_db which "agrees"
static int
thread_db_load_search (void)
{
- VEC (char_ptr) *dir_vec;
- struct cleanup *cleanups;
- char *this_dir;
- int i, rc = 0;
+ int rc = 0;
- dir_vec = dirnames_to_char_ptr_vec (libthread_db_search_path);
- cleanups = make_cleanup_free_char_ptr_vec (dir_vec);
+ std::vector<gdb::unique_xmalloc_ptr<char>> dir_vec
+ = dirnames_to_char_ptr_vec (libthread_db_search_path);
- for (i = 0; VEC_iterate (char_ptr, dir_vec, i, this_dir); ++i)
+ for (const gdb::unique_xmalloc_ptr<char> &this_dir_up : dir_vec)
{
+ const char *this_dir = this_dir_up.get ();
const int pdir_len = sizeof ("$pdir") - 1;
size_t this_dir_len;
&& (this_dir[pdir_len] == '\0'
|| this_dir[pdir_len] == '/'))
{
- char *subdir = NULL;
- struct cleanup *free_subdir_cleanup
- = make_cleanup (null_cleanup, NULL);
+ const char *subdir = NULL;
+ std::string subdir_holder;
if (this_dir[pdir_len] == '/')
{
- subdir = xmalloc (strlen (this_dir));
- make_cleanup (xfree, subdir);
- strcpy (subdir, this_dir + pdir_len + 1);
+ subdir_holder = std::string (this_dir + pdir_len + 1);
+ subdir = subdir_holder.c_str ();
}
rc = try_thread_db_load_from_pdir (subdir);
- do_cleanups (free_subdir_cleanup);
if (rc)
break;
}
}
}
- do_cleanups (cleanups);
if (libthread_db_debug)
fprintf_unfiltered (gdb_stdlog,
_("thread_db_load_search returning %d\n"), rc);
return 0;
}
-static void
-disable_thread_event_reporting (struct thread_db_info *info)
-{
- if (info->td_ta_clear_event_p != NULL)
- {
- td_thr_events_t events;
-
- /* Set the process wide mask saying we aren't interested in any
- events anymore. */
- td_event_fillset (&events);
- info->td_ta_clear_event_p (info->thread_agent, &events);
- }
-
- info->td_create_bp_addr = 0;
- info->td_death_bp_addr = 0;
-}
-
static void
check_thread_signals (void)
{
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.
+ the time gdb::observers::new_objfile.notify 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
{
warning (_ ("Target and debugger are in different PID "
"namespaces; thread lists and other data are "
- "likely unreliable"));
+ "likely unreliable. "
+ "Connect to gdbserver inside the container."));
}
}
}
from libthread_db thread state information. */
static void
-update_thread_state (struct private_thread_info *priv,
+update_thread_state (thread_db_thread_info *priv,
const td_thrinfo_t *ti_p)
{
priv->dying = (ti_p->ti_state == TD_THR_UNKNOWN
|| ti_p->ti_state == TD_THR_ZOMBIE);
}
-/* Attach to a new thread. This function is called when we receive a
- TD_CREATE event or when we iterate over all threads and find one
- that wasn't already in our list. Returns true on success. */
-
-static int
-attach_thread (ptid_t ptid, const td_thrhandle_t *th_p,
- const td_thrinfo_t *ti_p)
-{
- struct thread_info *tp;
- struct thread_db_info *info;
-
- /* If we're being called after a TD_CREATE event, we may already
- know about this thread. There are two ways this can happen. We
- may have iterated over all threads between the thread creation
- and the TD_CREATE event, for instance when the user has issued
- the `info threads' command before the SIGTRAP for hitting the
- thread creation breakpoint was reported. Alternatively, the
- thread may have exited and a new one been created with the same
- thread ID. In the first case we don't need to do anything; in
- the second case we should discard information about the dead
- thread and attach to the new one. */
- tp = find_thread_ptid (ptid);
- if (tp != NULL)
- {
- /* If tp->priv is NULL, then GDB is already attached to this
- thread, but we do not know anything about it. We can learn
- about it here. This can only happen if we have some other
- way besides libthread_db to notice new threads (i.e.
- PTRACE_EVENT_CLONE); assume the same mechanism notices thread
- exit, so this can not be a stale thread recreated with the
- same ID. */
- if (tp->priv != NULL)
- {
- if (!tp->priv->dying)
- return 0;
-
- delete_thread (ptid);
- tp = NULL;
- }
- }
-
- /* Under GNU/Linux, we have to attach to each and every thread. */
- if (target_has_execution
- && tp == NULL)
- {
- int res;
-
- res = lin_lwp_attach_lwp (ptid_build (ptid_get_pid (ptid),
- ti_p->ti_lid, 0));
- if (res < 0)
- {
- /* Error, stop iterating. */
- return 0;
- }
- else if (res > 0)
- {
- /* Pretend this thread doesn't exist yet, and keep
- iterating. */
- return 1;
- }
-
- /* Otherwise, we sucessfully attached to the thread. */
- }
-
- info = get_thread_db_info (ptid_get_pid (ptid));
- record_thread (info, tp, ptid, th_p, ti_p);
- return 1;
-}
-
/* Record a new thread in GDB's thread list. Creates the thread's
- private info. If TP is NULL, creates a new thread. Otherwise,
- uses TP. */
+ private info. If TP is NULL or TP is marked as having exited,
+ creates a new thread. Otherwise, uses TP. */
-static void
+static struct thread_info *
record_thread (struct thread_db_info *info,
struct thread_info *tp,
ptid_t ptid, const td_thrhandle_t *th_p,
const td_thrinfo_t *ti_p)
{
- td_err_e err;
- struct private_thread_info *priv;
- int new_thread = (tp == NULL);
-
/* A thread ID of zero may mean the thread library has not
initialized yet. Leave private == NULL until the thread library
has initialized. */
if (ti_p->ti_tid == 0)
- return;
+ return tp;
/* Construct the thread's private data. */
- priv = xmalloc (sizeof (struct private_thread_info));
- memset (priv, 0, sizeof (struct private_thread_info));
+ thread_db_thread_info *priv = new thread_db_thread_info;
priv->th = *th_p;
priv->tid = ti_p->ti_tid;
if (tp == NULL || tp->state == THREAD_EXITED)
tp = add_thread_with_info (ptid, priv);
else
- tp->priv = priv;
-
- /* Enable thread event reporting for this thread, except when
- debugging a core file. */
- if (target_has_execution && thread_db_use_events () && new_thread)
- {
- err = info->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));
- }
+ tp->priv.reset (priv);
if (target_has_execution)
check_thread_signals ();
-}
-static void
-detach_thread (ptid_t ptid)
-{
- struct thread_info *thread_info;
-
- /* Don't delete the thread now, because it still reports as active
- until it has executed a few instructions after the event
- breakpoint - if we deleted it now, "info threads" would cause us
- to re-attach to it. Just mark it as having had a TD_DEATH
- event. This means that we won't delete it from our thread list
- until we notice that it's dead (via prune_threads), or until
- something re-uses its thread ID. We'll report the thread exit
- when the underlying LWP dies. */
- thread_info = find_thread_ptid (ptid);
- gdb_assert (thread_info != NULL && thread_info->priv != NULL);
- thread_info->priv->dying = 1;
+ return tp;
}
static void
-thread_db_detach (struct target_ops *ops, const char *args, int from_tty)
+thread_db_detach (struct target_ops *ops, inferior *inf, int from_tty)
{
struct target_ops *target_beneath = find_target_beneath (ops);
- struct thread_db_info *info;
- info = get_thread_db_info (ptid_get_pid (inferior_ptid));
-
- if (info)
- {
- if (target_has_execution && thread_db_use_events ())
- {
- disable_thread_event_reporting (info);
-
- /* Delete the old thread event breakpoints. Note that
- unlike when mourning, we can remove them here because
- there's still a live inferior to poke at. In any case,
- GDB will not try to insert anything in the inferior when
- removing a breakpoint. */
- remove_thread_event_breakpoints ();
- }
-
- delete_thread_db_info (ptid_get_pid (inferior_ptid));
- }
+ delete_thread_db_info (inf->pid);
- target_beneath->to_detach (target_beneath, args, from_tty);
+ target_beneath->to_detach (target_beneath, inf, from_tty);
/* NOTE: From this point on, inferior_ptid is null_ptid. */
unpush_target (&thread_db_ops);
}
-/* Check if PID is currently stopped at the location of a thread event
- breakpoint location. If it is, read the event message and act upon
- the event. */
-
-static void
-check_event (ptid_t ptid)
-{
- struct regcache *regcache = get_thread_regcache (ptid);
- struct gdbarch *gdbarch = get_regcache_arch (regcache);
- td_event_msg_t msg;
- td_thrinfo_t ti;
- td_err_e err;
- CORE_ADDR stop_pc;
- int loop = 0;
- struct thread_db_info *info;
-
- info = get_thread_db_info (ptid_get_pid (ptid));
-
- /* Bail out early if we're not at a thread event breakpoint. */
- stop_pc = regcache_read_pc (regcache);
- if (!target_supports_stopped_by_sw_breakpoint ())
- stop_pc -= gdbarch_decr_pc_after_break (gdbarch);
-
- if (stop_pc != info->td_create_bp_addr
- && stop_pc != info->td_death_bp_addr)
- return;
-
- /* Access an lwp we know is stopped. */
- info->proc_handle.ptid = ptid;
-
- /* If we have only looked at the first thread before libpthread was
- initialized, we may not know its thread ID yet. Make sure we do
- before we add another thread to the list. */
- if (!have_threads (ptid))
- thread_db_find_new_threads_1 (ptid);
-
- /* If we are at a create breakpoint, we do not know what new lwp
- was created and cannot specifically locate the event message for it.
- We have to call td_ta_event_getmsg() to get
- the latest message. Since we have no way of correlating whether
- the event message we get back corresponds to our breakpoint, we must
- loop and read all event messages, processing them appropriately.
- This guarantees we will process the correct message before continuing
- from the breakpoint.
-
- Currently, death events are not enabled. If they are enabled,
- the death event can use the td_thr_event_getmsg() interface to
- get the message specifically for that lwp and avoid looping
- below. */
-
- loop = 1;
-
- do
- {
- err = info->td_ta_event_getmsg_p (info->thread_agent, &msg);
- if (err != TD_OK)
- {
- if (err == TD_NOMSG)
- return;
-
- error (_("Cannot get thread event message: %s"),
- thread_db_err_str (err));
- }
-
- err = info->td_thr_get_info_p (msg.th_p, &ti);
- if (err != TD_OK)
- error (_("Cannot get thread info: %s"), thread_db_err_str (err));
-
- ptid = ptid_build (ptid_get_pid (ptid), ti.ti_lid, 0);
-
- switch (msg.event)
- {
- case TD_CREATE:
- /* Call attach_thread whether or not we already know about a
- thread with this thread ID. */
- attach_thread (ptid, msg.th_p, &ti);
-
- break;
-
- case TD_DEATH:
-
- if (!in_thread_list (ptid))
- error (_("Spurious thread death event."));
-
- detach_thread (ptid);
-
- break;
-
- default:
- error (_("Spurious thread event."));
- }
- }
- while (loop);
-}
-
static ptid_t
thread_db_wait (struct target_ops *ops,
ptid_t ptid, struct target_waitstatus *ourstatus,
ptid = beneath->to_wait (beneath, ptid, ourstatus, options);
- if (ourstatus->kind == TARGET_WAITKIND_IGNORE)
- return ptid;
-
- if (ourstatus->kind == TARGET_WAITKIND_EXITED
- || ourstatus->kind == TARGET_WAITKIND_SIGNALLED)
- return ptid;
+ switch (ourstatus->kind)
+ {
+ case TARGET_WAITKIND_IGNORE:
+ case TARGET_WAITKIND_EXITED:
+ case TARGET_WAITKIND_THREAD_EXITED:
+ case TARGET_WAITKIND_SIGNALLED:
+ return ptid;
+ }
info = get_thread_db_info (ptid_get_pid (ptid));
if (!thread_db_list)
unpush_target (&thread_db_ops);
- /* Thread event breakpoints are deleted by
- update_breakpoints_after_exec. */
-
return ptid;
}
- if (ourstatus->kind == TARGET_WAITKIND_STOPPED
- && ourstatus->value.sig == GDB_SIGNAL_TRAP)
- /* Check for a thread event. */
- check_event (ptid);
-
/* Fill in the thread's user-level thread id and status. */
thread_from_lwp (ptid);
target_beneath->to_mourn_inferior (target_beneath);
- /* Delete the old thread event breakpoints. Do this after mourning
- the inferior, so that we don't try to uninsert them. */
- remove_thread_event_breakpoints ();
-
/* Detach thread_db target ops. */
if (!thread_db_list)
unpush_target (ops);
td_err_e err;
ptid_t ptid;
struct thread_info *tp;
- struct callback_data *cb_data = data;
+ struct callback_data *cb_data = (struct callback_data *) data;
struct thread_db_info *info = cb_data->info;
err = info->td_thr_get_info_p (th_p, &ti);
if (libthread_db_debug)
fprintf_unfiltered (gdb_stdlog,
"thread_db: skipping exited and "
- "joined thread (0x%lx)\n", ti.ti_tid);
+ "joined thread (0x%lx)\n",
+ (unsigned long) ti.ti_tid);
return 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. */
+ be yet. */
/* In that case, we're not stopped in a fork syscall and don't
need this glibc bug workaround. */
info->need_stale_parent_threads_check = 0;
- if (target_has_execution && thread_db_use_events ())
- {
- err = info->td_thr_event_enable_p (th_p, 1);
- if (err != TD_OK)
- error (_("Cannot enable thread event reporting for LWP %d: %s"),
- (int) ti.ti_lid, thread_db_err_str (err));
- }
-
return 0;
}
ptid = ptid_build (info->pid, ti.ti_lid, 0);
tp = find_thread_ptid (ptid);
if (tp == NULL || tp->priv == NULL)
- {
- if (attach_thread (ptid, th_p, &ti))
- cb_data->new_threads += 1;
- else
- /* Problem attaching this thread; perhaps it exited before we
- could attach it?
- This could mean that the thread list inside glibc itself is in
- inconsistent state, and libthread_db could go on looping forever
- (observed with glibc-2.3.6). To prevent that, terminate
- iteration: thread_db_find_new_threads_2 will retry. */
- return 1;
- }
- else if (target_has_execution && !thread_db_use_events ())
- {
- /* Need to update this if not using the libthread_db events
- (particularly, the TD_DEATH event). */
- update_thread_state (tp->priv, &ti);
- }
+ record_thread (info, tp, ptid, th_p, &ti);
return 0;
}
data.new_threads = 0;
/* See comment in thread_db_update_thread_list. */
- gdb_assert (!target_has_execution || thread_db_use_events ());
+ gdb_assert (info->td_ta_thr_iter_p != NULL);
TRY
{
thread_db_find_new_threads_2 (ptid, 0);
}
-static int
-update_thread_core (struct lwp_info *info, void *closure)
-{
- info->core = linux_common_core_of_thread (info->ptid);
- return 0;
-}
-
-/* Update the thread list using td_ta_thr_iter. */
+/* Implement the to_update_thread_list target method for this
+ target. */
static void
-thread_db_update_thread_list_td_ta_thr_iter (struct target_ops *ops)
+thread_db_update_thread_list (struct target_ops *ops)
{
struct thread_db_info *info;
struct inferior *inf;
if (thread == NULL || thread->executing)
continue;
+ /* It's best to avoid td_ta_thr_iter if possible. That walks
+ data structures in the inferior's address space that may be
+ corrupted, or, if the target is running, the list may change
+ while we walk it. In the latter case, it's possible that a
+ thread exits just at the exact time that causes GDB to get
+ stuck in an infinite loop. To avoid pausing all threads
+ whenever the core wants to refresh the thread list, we
+ instead use thread_from_lwp immediately when we see an LWP
+ stop. That uses thread_db entry points that do not walk
+ libpthread's thread list, so should be safe, as well as more
+ efficient. */
+ if (target_has_execution_1 (thread->ptid))
+ continue;
+
thread_db_find_new_threads_1 (thread->ptid);
}
-}
-
-/* Implement the to_update_thread_list target method for this
- target. */
-
-static void
-thread_db_update_thread_list (struct target_ops *ops)
-{
- /* It's best to avoid td_ta_thr_iter if possible. That walks data
- structures in the inferior's address space that may be corrupted,
- or, if the target is running, the list may change while we walk
- it. In the latter case, it's possible that a thread exits just
- at the exact time that causes GDB to get stuck in an infinite
- loop. To avoid pausing all threads whenever the core wants to
- refresh the thread list, if the kernel supports clone events
- (meaning we're always already attached to all LWPs), we use
- thread_from_lwp immediately when we see an LWP stop. That uses
- thread_db entry points that do not walk libpthread's thread list,
- so should be safe, as well as more efficient. */
- if (target_has_execution && !thread_db_use_events ())
- ops->beneath->to_update_thread_list (ops->beneath);
- else
- thread_db_update_thread_list_td_ta_thr_iter (ops);
- if (target_has_execution)
- iterate_over_lwps (minus_one_ptid /* iterate over all */,
- update_thread_core, NULL);
+ /* Give the beneath target a chance to do extra processing. */
+ ops->beneath->to_update_thread_list (ops->beneath);
}
-static char *
+static const char *
thread_db_pid_to_str (struct target_ops *ops, ptid_t ptid)
{
struct thread_info *thread_info = find_thread_ptid (ptid);
if (thread_info != NULL && thread_info->priv != NULL)
{
static char buf[64];
- thread_t tid;
+ thread_db_thread_info *priv = get_thread_db_thread_info (thread_info);
- tid = thread_info->priv->tid;
snprintf (buf, sizeof (buf), "Thread 0x%lx (LWP %ld)",
- tid, ptid_get_lwp (ptid));
+ (unsigned long) priv->tid, ptid_get_lwp (ptid));
return buf;
}
/* Return a string describing the state of the thread specified by
INFO. */
-static char *
+static const char *
thread_db_extra_thread_info (struct target_ops *self,
struct thread_info *info)
{
if (info->priv == NULL)
return NULL;
- if (info->priv->dying)
+ thread_db_thread_info *priv = get_thread_db_thread_info (info);
+
+ if (priv->dying)
return "Exiting";
return NULL;
}
+/* Return pointer to the thread_info struct which corresponds to
+ THREAD_HANDLE (having length HANDLE_LEN). */
+
+static struct thread_info *
+thread_db_thread_handle_to_thread_info (struct target_ops *ops,
+ const gdb_byte *thread_handle,
+ int handle_len,
+ struct inferior *inf)
+{
+ struct thread_info *tp;
+ thread_t handle_tid;
+
+ /* Thread handle sizes must match in order to proceed. We don't use an
+ assert here because the resulting internal error will cause GDB to
+ exit. This isn't necessarily an internal error due to the possibility
+ of garbage being passed as the thread handle via the python interface. */
+ if (handle_len != sizeof (handle_tid))
+ error (_("Thread handle size mismatch: %d vs %zu (from libthread_db)"),
+ handle_len, sizeof (handle_tid));
+
+ handle_tid = * (const thread_t *) thread_handle;
+
+ ALL_NON_EXITED_THREADS (tp)
+ {
+ thread_db_thread_info *priv = get_thread_db_thread_info (tp);
+
+ if (tp->inf == inf && priv != NULL && handle_tid == priv->tid)
+ return tp;
+ }
+
+ return NULL;
+}
+
/* 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. */
struct thread_info *thread_info;
struct target_ops *beneath;
- /* If we have not discovered any threads yet, check now. */
- if (!have_threads (ptid))
- thread_db_find_new_threads_1 (ptid);
-
/* Find the matching thread. */
thread_info = find_thread_ptid (ptid);
+ /* We may not have discovered the thread yet. */
+ if (thread_info != NULL && thread_info->priv == NULL)
+ thread_info = thread_from_lwp (ptid);
+
if (thread_info != NULL && thread_info->priv != NULL)
{
td_err_e err;
psaddr_t address;
- struct thread_db_info *info;
-
- info = get_thread_db_info (ptid_get_pid (ptid));
+ thread_db_info *info = get_thread_db_info (ptid_get_pid (ptid));
+ thread_db_thread_info *priv = get_thread_db_thread_info (thread_info);
/* Finally, get the address of the variable. */
if (lm != 0)
/* Note the cast through uintptr_t: this interface only works if
a target address fits in a psaddr_t, which is a host pointer.
So a 32-bit debugger can not access 64-bit TLS through this. */
- err = info->td_thr_tls_get_addr_p (&thread_info->priv->th,
+ err = info->td_thr_tls_get_addr_p (&priv->th,
(psaddr_t)(uintptr_t) lm,
offset, &address);
}
PR libc/16831 due to GDB PR threads/16954 LOAD_MODULE is also NULL.
The constant number 1 depends on GNU __libc_setup_tls
initialization of l_tls_modid to 1. */
- err = info->td_thr_tlsbase_p (&thread_info->priv->th,
- 1, &address);
+ err = info->td_thr_tlsbase_p (&priv->th, 1, &address);
address = (char *) address + offset;
}
beneath->to_resume (beneath, ptid, step, signo);
}
-/* qsort helper function for info_auto_load_libthread_db, sort the
+/* std::sort helper function for info_auto_load_libthread_db, sort the
thread_db_info pointers primarily by their FILENAME and secondarily by their
PID, both in ascending order. */
-static int
-info_auto_load_libthread_db_compare (const void *ap, const void *bp)
+static bool
+info_auto_load_libthread_db_compare (const struct thread_db_info *a,
+ const struct thread_db_info *b)
{
- struct thread_db_info *a = *(struct thread_db_info **) ap;
- struct thread_db_info *b = *(struct thread_db_info **) bp;
int retval;
retval = strcmp (a->filename, b->filename);
if (retval)
- return retval;
+ return retval < 0;
- return (a->pid > b->pid) - (a->pid - b->pid);
+ return a->pid < b->pid;
}
/* Implement 'info auto-load libthread-db'. */
static void
-info_auto_load_libthread_db (char *args, int from_tty)
+info_auto_load_libthread_db (const char *args, int from_tty)
{
struct ui_out *uiout = current_uiout;
const char *cs = args ? args : "";
- struct thread_db_info *info, **array;
- unsigned info_count, unique_filenames;
- size_t max_filename_len, max_pids_len, pids_len;
- struct cleanup *back_to;
- char *pids;
+ struct thread_db_info *info;
+ unsigned unique_filenames;
+ size_t max_filename_len, pids_len;
int i;
- cs = skip_spaces_const (cs);
+ cs = skip_spaces (cs);
if (*cs)
error (_("'info auto-load libthread-db' does not accept any parameters"));
- info_count = 0;
- for (info = thread_db_list; info; info = info->next)
- if (info->filename != NULL)
- info_count++;
-
- array = xmalloc (sizeof (*array) * info_count);
- back_to = make_cleanup (xfree, array);
-
- info_count = 0;
+ std::vector<struct thread_db_info *> array;
for (info = thread_db_list; info; info = info->next)
if (info->filename != NULL)
- array[info_count++] = info;
+ array.push_back (info);
/* Sort ARRAY by filenames and PIDs. */
-
- qsort (array, info_count, sizeof (*array),
- info_auto_load_libthread_db_compare);
+ std::sort (array.begin (), array.end (),
+ info_auto_load_libthread_db_compare);
/* Calculate the number of unique filenames (rows) and the maximum string
length of PIDs list for the unique filenames (columns). */
unique_filenames = 0;
max_filename_len = 0;
- max_pids_len = 0;
pids_len = 0;
- for (i = 0; i < info_count; i++)
+ for (i = 0; i < array.size (); i++)
{
int pid = array[i]->pid;
size_t this_pid_len;
if (i == 0 || strcmp (array[i - 1]->filename, array[i]->filename) != 0)
{
unique_filenames++;
- max_filename_len = max (max_filename_len,
- strlen (array[i]->filename));
+ max_filename_len = std::max (max_filename_len,
+ strlen (array[i]->filename));
if (i > 0)
- {
- pids_len -= strlen (", ");
- max_pids_len = max (max_pids_len, pids_len);
- }
+ pids_len -= strlen (", ");
pids_len = 0;
}
pids_len += this_pid_len + strlen (", ");
}
if (i)
- {
- pids_len -= strlen (", ");
- max_pids_len = max (max_pids_len, pids_len);
- }
+ pids_len -= strlen (", ");
/* Table header shifted right by preceding "libthread-db: " would not match
its columns. */
- if (info_count > 0 && args == auto_load_info_scripts_pattern_nl)
- ui_out_text (uiout, "\n");
-
- make_cleanup_ui_out_table_begin_end (uiout, 2, unique_filenames,
- "LinuxThreadDbTable");
-
- ui_out_table_header (uiout, max_filename_len, ui_left, "filename",
- "Filename");
- ui_out_table_header (uiout, pids_len, ui_left, "PIDs", "Pids");
- ui_out_table_body (uiout);
+ if (array.size () > 0 && args == auto_load_info_scripts_pattern_nl)
+ uiout->text ("\n");
- pids = xmalloc (max_pids_len + 1);
- make_cleanup (xfree, pids);
+ {
+ ui_out_emit_table table_emitter (uiout, 2, unique_filenames,
+ "LinuxThreadDbTable");
- /* Note I is incremented inside the cycle, not at its end. */
- for (i = 0; i < info_count;)
- {
- struct cleanup *chain = make_cleanup_ui_out_tuple_begin_end (uiout, NULL);
- char *pids_end;
-
- info = array[i];
- ui_out_field_string (uiout, "filename", info->filename);
- pids_end = pids;
+ uiout->table_header (max_filename_len, ui_left, "filename", "Filename");
+ uiout->table_header (pids_len, ui_left, "PIDs", "Pids");
+ uiout->table_body ();
- while (i < info_count && strcmp (info->filename, array[i]->filename) == 0)
- {
- if (pids_end != pids)
- {
- *pids_end++ = ',';
- *pids_end++ = ' ';
- }
- pids_end += xsnprintf (pids_end, &pids[max_pids_len + 1] - pids_end,
- "%u", array[i]->pid);
- gdb_assert (pids_end < &pids[max_pids_len + 1]);
+ /* Note I is incremented inside the cycle, not at its end. */
+ for (i = 0; i < array.size ();)
+ {
+ ui_out_emit_tuple tuple_emitter (uiout, NULL);
- i++;
- }
- *pids_end = '\0';
+ info = array[i];
+ uiout->field_string ("filename", info->filename);
- ui_out_field_string (uiout, "pids", pids);
+ std::string pids;
+ while (i < array.size () && strcmp (info->filename,
+ array[i]->filename) == 0)
+ {
+ if (!pids.empty ())
+ pids += ", ";
+ string_appendf (pids, "%u", array[i]->pid);
+ i++;
+ }
- ui_out_text (uiout, "\n");
- do_cleanups (chain);
- }
+ uiout->field_string ("pids", pids.c_str ());
- do_cleanups (back_to);
+ uiout->text ("\n");
+ }
+ }
- if (info_count == 0)
- ui_out_message (uiout, 0, _("No auto-loaded libthread-db.\n"));
+ if (array.empty ())
+ uiout->message (_("No auto-loaded libthread-db.\n"));
}
static void
= thread_db_get_thread_local_address;
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_thread_handle_to_thread_info = thread_db_thread_handle_to_thread_info;
thread_db_ops.to_magic = OPS_MAGIC;
complete_target_initialization (&thread_db_ops);
}
-/* Provide a prototype to silence -Wmissing-prototypes. */
-extern initialize_file_ftype _initialize_thread_db;
-
void
_initialize_thread_db (void)
{
/* Defer loading of libthread_db.so until inferior is running.
This allows gdb to load correct libthread_db for a given
- executable -- there could be mutiple versions of glibc,
- compiled with LinuxThreads or NPTL, and until there is
- a running inferior, we can't tell which libthread_db is
- the correct one to load. */
+ executable -- there could be multiple versions of glibc,
+ and until there is a running inferior, we can't tell which
+ libthread_db is the correct one to load. */
libthread_db_search_path = xstrdup (LIBTHREAD_DB_SEARCH_PATH);
auto_load_info_cmdlist_get ());
/* Add ourselves to objfile event chain. */
- observer_attach_new_objfile (thread_db_new_objfile);
+ gdb::observers::new_objfile.attach (thread_db_new_objfile);
/* Add ourselves to inferior_created event chain.
This is needed to handle debugging statically linked programs where
the new_objfile observer won't get called for libpthread. */
- observer_attach_inferior_created (thread_db_inferior_created);
+ gdb::observers::inferior_created.attach (thread_db_inferior_created);
}