#include <sys/ptrace.h>
#include "linux-nat.h"
#include "linux-ptrace.h"
+#include "linux-procfs.h"
#include "linux-fork.h"
#include "gdbthread.h"
#include "gdbcmd.h"
value);
}
-static int disable_randomization = 1;
-
-static void
-show_disable_randomization (struct ui_file *file, int from_tty,
- struct cmd_list_element *c, const char *value)
-{
-#ifdef HAVE_PERSONALITY
- fprintf_filtered (file,
- _("Disabling randomization of debuggee's "
- "virtual address space is %s.\n"),
- value);
-#else /* !HAVE_PERSONALITY */
- fputs_filtered (_("Disabling randomization of debuggee's "
- "virtual address space is unsupported on\n"
- "this platform.\n"), file);
-#endif /* !HAVE_PERSONALITY */
-}
-
-static void
-set_disable_randomization (char *args, int from_tty,
- struct cmd_list_element *c)
-{
-#ifndef HAVE_PERSONALITY
- error (_("Disabling randomization of debuggee's "
- "virtual address space is unsupported on\n"
- "this platform."));
-#endif /* !HAVE_PERSONALITY */
-}
-
struct simple_pid_list
{
int pid;
*listp = new_pid;
}
+static int
+in_pid_list_p (struct simple_pid_list *list, int pid)
+{
+ struct simple_pid_list *p;
+
+ for (p = list; p != NULL; p = p->next)
+ if (p->pid == pid)
+ return 1;
+ return 0;
+}
+
static int
pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp)
{
return 0;
}
-static void
-linux_record_stopped_pid (int pid, int status)
-{
- add_to_pid_list (&stopped_pids, pid, status);
-}
-
\f
/* A helper function for linux_test_for_tracefork, called after fork (). */
add_thread (inferior_ptid);
child_lp = add_lwp (inferior_ptid);
child_lp->stopped = 1;
- child_lp->resumed = 1;
+ child_lp->last_resume_kind = resume_stop;
/* If this is a vfork child, then the address-space is
shared with the parent. */
if (has_vforked)
{
- struct lwp_info *lp;
+ struct lwp_info *parent_lp;
struct inferior *parent_inf;
parent_inf = current_inferior ();
parent_inf->waiting_for_vfork_done = detach_fork;
parent_inf->pspace->breakpoints_not_allowed = detach_fork;
- lp = find_lwp_pid (pid_to_ptid (parent_pid));
+ parent_lp = find_lwp_pid (pid_to_ptid (parent_pid));
gdb_assert (linux_supports_tracefork_flag >= 0);
+
if (linux_supports_tracevforkdone (0))
{
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
"LCFF: waiting for VFORK_DONE on %d\n",
parent_pid);
-
- lp->stopped = 1;
- lp->resumed = 1;
+ parent_lp->stopped = 1;
/* We'll handle the VFORK_DONE event like any other
event, in target_wait. */
and leave it pending. The next linux_nat_resume call
will notice a pending event, and bypasses actually
resuming the inferior. */
- lp->status = 0;
- lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE;
- lp->stopped = 0;
- lp->resumed = 1;
+ parent_lp->status = 0;
+ parent_lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE;
+ parent_lp->stopped = 1;
/* If we're in async mode, need to tell the event loop
there's something here to process. */
else
{
struct inferior *parent_inf, *child_inf;
- struct lwp_info *lp;
+ struct lwp_info *child_lp;
struct program_space *parent_pspace;
if (info_verbose || debug_linux_nat)
inferior_ptid = ptid_build (child_pid, child_pid, 0);
add_thread (inferior_ptid);
- lp = add_lwp (inferior_ptid);
- lp->stopped = 1;
- lp->resumed = 1;
+ child_lp = add_lwp (inferior_ptid);
+ child_lp->stopped = 1;
+ child_lp->last_resume_kind = resume_stop;
/* If this is a vfork child, then the address-space is shared
with the parent. If we detached from the parent, then we can
memset (lp, 0, sizeof (struct lwp_info));
+ lp->last_resume_kind = resume_continue;
lp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
lp->ptid = ptid;
delete_lwp (lp->ptid);
}
-/* Return an lwp's tgid, found in `/proc/PID/status'. */
-
-int
-linux_proc_get_tgid (int lwpid)
-{
- FILE *status_file;
- char buf[100];
- int tgid = -1;
-
- snprintf (buf, sizeof (buf), "/proc/%d/status", (int) lwpid);
- status_file = fopen (buf, "r");
- if (status_file != NULL)
- {
- while (fgets (buf, sizeof (buf), status_file))
- {
- if (strncmp (buf, "Tgid:", 5) == 0)
- {
- tgid = strtoul (buf + strlen ("Tgid:"), NULL, 10);
- break;
- }
- }
-
- fclose (status_file);
- }
-
- return tgid;
-}
-
/* Detect `T (stopped)' in `/proc/PID/status'.
Other states including `T (tracing stop)' are reported as false. */
return status;
}
-/* Attach to the LWP specified by PID. Return 0 if successful or -1
- if the new LWP could not be attached. */
+/* Attach to the LWP specified by PID. Return 0 if successful, -1 if
+ the new LWP could not be attached, or 1 if we're already auto
+ attached to this thread, but haven't processed the
+ PTRACE_EVENT_CLONE event of its parent thread, so we just ignore
+ its existance, without considering it an error. */
int
lin_lwp_attach_lwp (ptid_t ptid)
{
struct lwp_info *lp;
sigset_t prev_mask;
+ int lwpid;
gdb_assert (is_lwp (ptid));
block_child_signals (&prev_mask);
lp = find_lwp_pid (ptid);
+ lwpid = GET_LWP (ptid);
/* We assume that we're already attached to any LWP that has an id
equal to the overall process id, and to any LWP that is already
and we've had PID wraparound since we last tried to stop all threads,
this assumption might be wrong; fortunately, this is very unlikely
to happen. */
- if (GET_LWP (ptid) != GET_PID (ptid) && lp == NULL)
+ if (lwpid != GET_PID (ptid) && lp == NULL)
{
int status, cloned = 0, signalled = 0;
- if (ptrace (PTRACE_ATTACH, GET_LWP (ptid), 0, 0) < 0)
+ if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0)
{
+ if (linux_supports_tracefork_flag)
+ {
+ /* If we haven't stopped all threads when we get here,
+ we may have seen a thread listed in thread_db's list,
+ but not processed the PTRACE_EVENT_CLONE yet. If
+ that's the case, ignore this new thread, and let
+ normal event handling discover it later. */
+ if (in_pid_list_p (stopped_pids, lwpid))
+ {
+ /* We've already seen this thread stop, but we
+ haven't seen the PTRACE_EVENT_CLONE extended
+ event yet. */
+ restore_child_signals_mask (&prev_mask);
+ return 0;
+ }
+ else
+ {
+ int new_pid;
+ int status;
+
+ /* See if we've got a stop for this new child
+ pending. If so, we're already attached. */
+ new_pid = my_waitpid (lwpid, &status, WNOHANG);
+ if (new_pid == -1 && errno == ECHILD)
+ new_pid = my_waitpid (lwpid, &status, __WCLONE | WNOHANG);
+ if (new_pid != -1)
+ {
+ if (WIFSTOPPED (status))
+ add_to_pid_list (&stopped_pids, lwpid, status);
+
+ restore_child_signals_mask (&prev_mask);
+ return 1;
+ }
+ }
+ }
+
/* If we fail to attach to the thread, issue a warning,
but continue. One way this can happen is if thread
creation is interrupted; as of Linux kernel 2.6.19, a
if (!WIFSTOPPED (status))
{
restore_child_signals_mask (&prev_mask);
- return -1;
+ return 1;
}
lp = add_lwp (ptid);
lp->stopped = 1;
}
+ lp->last_resume_kind = resume_stop;
restore_child_signals_mask (&prev_mask);
return 0;
}
/* Resume LP. */
-static int
-resume_callback (struct lwp_info *lp, void *data)
+static void
+resume_lwp (struct lwp_info *lp, int step)
{
- struct inferior *inf = find_inferior_pid (GET_PID (lp->ptid));
-
- if (lp->stopped && inf->vfork_child != NULL)
+ if (lp->stopped)
{
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "RC: Not resuming %s (vfork parent)\n",
- target_pid_to_str (lp->ptid));
+ struct inferior *inf = find_inferior_pid (GET_PID (lp->ptid));
+
+ if (inf->vfork_child != NULL)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "RC: Not resuming %s (vfork parent)\n",
+ target_pid_to_str (lp->ptid));
+ }
+ else if (lp->status == 0
+ && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "RC: PTRACE_CONT %s, 0, 0 (resuming sibling)\n",
+ target_pid_to_str (lp->ptid));
+
+ linux_ops->to_resume (linux_ops,
+ pid_to_ptid (GET_LWP (lp->ptid)),
+ step, TARGET_SIGNAL_0);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "RC: PTRACE_CONT %s, 0, 0 (resume sibling)\n",
+ target_pid_to_str (lp->ptid));
+ lp->stopped = 0;
+ lp->step = step;
+ memset (&lp->siginfo, 0, sizeof (lp->siginfo));
+ lp->stopped_by_watchpoint = 0;
+ }
+ else
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "RC: Not resuming sibling %s (has pending)\n",
+ target_pid_to_str (lp->ptid));
+ }
}
- else if (lp->stopped && lp->status == 0)
+ else
{
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
- "RC: PTRACE_CONT %s, 0, 0 (resuming sibling)\n",
+ "RC: Not resuming sibling %s (not stopped)\n",
target_pid_to_str (lp->ptid));
-
- linux_ops->to_resume (linux_ops,
- pid_to_ptid (GET_LWP (lp->ptid)),
- 0, TARGET_SIGNAL_0);
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "RC: PTRACE_CONT %s, 0, 0 (resume sibling)\n",
- target_pid_to_str (lp->ptid));
- lp->stopped = 0;
- lp->step = 0;
- memset (&lp->siginfo, 0, sizeof (lp->siginfo));
- lp->stopped_by_watchpoint = 0;
}
- else if (lp->stopped && debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "RC: Not resuming sibling %s (has pending)\n",
- target_pid_to_str (lp->ptid));
- else if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "RC: Not resuming sibling %s (not stopped)\n",
- target_pid_to_str (lp->ptid));
+}
+static int
+resume_callback (struct lwp_info *lp, void *data)
+{
+ resume_lwp (lp, 0);
return 0;
}
resume_clear_callback (struct lwp_info *lp, void *data)
{
lp->resumed = 0;
+ lp->last_resume_kind = resume_stop;
return 0;
}
resume_set_callback (struct lwp_info *lp, void *data)
{
lp->resumed = 1;
+ lp->last_resume_kind = resume_continue;
return 0;
}
/* Remember if we're stepping. */
lp->step = step;
+ lp->last_resume_kind = step ? resume_step : resume_continue;
/* If we have a pending wait status for this thread, there is no
point in resuming the process. But first make sure that
new_lp->stopped = 0;
new_lp->resumed = 1;
+ new_lp->last_resume_kind = resume_continue;
signo = (status
? target_signal_from_host (WSTOPSIG (status))
pid = my_waitpid (GET_LWP (lp->ptid), &status, WNOHANG);
if (pid == -1 && errno == ECHILD)
pid = my_waitpid (GET_LWP (lp->ptid), &status, __WCLONE | WNOHANG);
+ if (pid == -1 && errno == ECHILD)
+ {
+ /* The thread has previously exited. We need to delete it
+ now because, for some vendor 2.4 kernels with NPTL
+ support backported, there won't be an exit event unless
+ it is the main thread. 2.6 kernels will report an exit
+ event for each thread that exits, as expected. */
+ thread_dead = 1;
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n",
+ target_pid_to_str (lp->ptid));
+ }
if (pid != 0)
break;
restore_child_signals_mask (&prev_mask);
- if (pid == -1 && errno == ECHILD)
- {
- /* The thread has previously exited. We need to delete it
- now because, for some vendor 2.4 kernels with NPTL
- support backported, there won't be an exit event unless
- it is the main thread. 2.6 kernels will report an exit
- event for each thread that exits, as expected. */
- thread_dead = 1;
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n",
- target_pid_to_str (lp->ptid));
- }
-
if (!thread_dead)
{
gdb_assert (pid == GET_LWP (lp->ptid));
target_pid_to_str (lp->ptid),
status_to_str (status));
}
- }
- /* Check if the thread has exited. */
- if (WIFEXITED (status) || WIFSIGNALED (status))
- {
- thread_dead = 1;
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n",
- target_pid_to_str (lp->ptid));
+ /* Check if the thread has exited. */
+ if (WIFEXITED (status) || WIFSIGNALED (status))
+ {
+ thread_dead = 1;
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n",
+ target_pid_to_str (lp->ptid));
+ }
}
if (thread_dead)
static int
running_callback (struct lwp_info *lp, void *data)
{
- return (lp->stopped == 0 || (lp->status != 0 && lp->resumed));
+ return (!lp->stopped
+ || ((lp->status != 0
+ || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE)
+ && lp->resumed));
}
/* Count the LWP's that have had events. */
static int
select_singlestep_lwp_callback (struct lwp_info *lp, void *data)
{
- if (lp->step && lp->status != 0)
+ if (lp->last_resume_kind == resume_step
+ && lp->status != 0)
return 1;
else
return 0;
static int
stop_and_resume_callback (struct lwp_info *lp, void *data)
{
- struct lwp_info *ptr;
-
- if (!lp->stopped && !lp->signalled)
+ if (!lp->stopped)
{
+ enum resume_kind last_resume_kind = lp->last_resume_kind;
+ ptid_t ptid = lp->ptid;
+
stop_callback (lp, NULL);
stop_wait_callback (lp, NULL);
- /* Resume if the lwp still exists. */
- for (ptr = lwp_list; ptr; ptr = ptr->next)
- if (lp == ptr)
- {
- resume_callback (lp, NULL);
- resume_set_callback (lp, NULL);
- }
+
+ /* Resume if the lwp still exists, and the core wanted it
+ running. */
+ if (last_resume_kind != resume_stop)
+ {
+ lp = find_lwp_pid (ptid);
+ if (lp)
+ resume_lwp (lp, lp->step);
+ }
}
return 0;
}
from waitpid before or after the event is. */
if (WIFSTOPPED (status) && !lp)
{
- linux_record_stopped_pid (lwpid, status);
+ add_to_pid_list (&stopped_pids, lwpid, status);
return NULL;
}
"LLW: Delayed SIGSTOP caught for %s.\n",
target_pid_to_str (lp->ptid));
- /* This is a delayed SIGSTOP. */
lp->signalled = 0;
- registers_changed ();
+ if (lp->last_resume_kind != resume_stop)
+ {
+ /* This is a delayed SIGSTOP. */
- linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
+ registers_changed ();
+
+ linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
lp->step, TARGET_SIGNAL_0);
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLW: %s %s, 0, 0 (discard SIGSTOP)\n",
- lp->step ?
- "PTRACE_SINGLESTEP" : "PTRACE_CONT",
- target_pid_to_str (lp->ptid));
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s %s, 0, 0 (discard SIGSTOP)\n",
+ lp->step ?
+ "PTRACE_SINGLESTEP" : "PTRACE_CONT",
+ target_pid_to_str (lp->ptid));
- lp->stopped = 0;
- gdb_assert (lp->resumed);
+ lp->stopped = 0;
+ gdb_assert (lp->resumed);
- /* Discard the event. */
- return NULL;
+ /* Discard the event. */
+ return NULL;
+ }
}
/* Make sure we don't report a SIGINT that we have already displayed
lp = NULL;
}
- if (lp && lp->signalled)
+ if (lp && lp->signalled && lp->last_resume_kind != resume_stop)
{
/* A pending SIGSTOP may interfere with the normal stream of
events. In a typical case where interference is a problem,
iterate_over_lwps (minus_one_ptid, resume_clear_callback, NULL);
}
else
- lp->resumed = 0;
+ {
+ lp->resumed = 0;
+ lp->last_resume_kind = resume_stop;
+ }
if (linux_nat_status_is_event (status))
{
restore_child_signals_mask (&prev_mask);
+ if (lp->last_resume_kind == resume_stop
+ && ourstatus->kind == TARGET_WAITKIND_STOPPED
+ && WSTOPSIG (status) == SIGSTOP)
+ {
+ /* A thread that has been requested to stop by GDB with
+ target_stop, and it stopped cleanly, so report as SIG0. The
+ use of SIGSTOP is an implementation detail. */
+ ourstatus->value.sig = TARGET_SIGNAL_0;
+ }
+
if (ourstatus->kind == TARGET_WAITKIND_EXITED
|| ourstatus->kind == TARGET_WAITKIND_SIGNALLED)
lp->core = -1;
return linux_multi_process;
}
+static int
+linux_nat_supports_disable_randomization (void)
+{
+#ifdef HAVE_PERSONALITY
+ return 1;
+#else
+ return 0;
+#endif
+}
+
static int async_terminal_is_ours = 1;
/* target_terminal_inferior implementation. */
target_pid_to_str (lwp->ptid));
- stop_callback (lwp, NULL);
- stop_wait_callback (lwp, NULL);
-
- /* If the lwp exits while we try to stop it, there's nothing
- else to do. */
- lwp = find_lwp_pid (ptid);
- if (lwp == NULL)
- return 0;
+ if (lwp->last_resume_kind == resume_stop)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "linux-nat: already stopping LWP %ld at "
+ "GDB's request\n",
+ ptid_get_lwp (lwp->ptid));
+ return 0;
+ }
- /* If we didn't collect any signal other than SIGSTOP while
- stopping the LWP, push a SIGNAL_0 event. In either case, the
- event-loop will end up calling target_wait which will collect
- these. */
- if (lwp->status == 0)
- lwp->status = W_STOPCODE (0);
- async_file_mark ();
+ stop_callback (lwp, NULL);
+ lwp->last_resume_kind = resume_stop;
}
else
{
t->to_supports_multi_process = linux_nat_supports_multi_process;
+ t->to_supports_disable_randomization
+ = linux_nat_supports_disable_randomization;
+
t->to_core_of_thread = linux_nat_core_of_thread;
/* We don't change the stratum; this target will sit at
sigdelset (&suspend_mask, SIGCHLD);
sigemptyset (&blocked_mask);
-
- add_setshow_boolean_cmd ("disable-randomization", class_support,
- &disable_randomization, _("\
-Set disabling of debuggee's virtual address space randomization."), _("\
-Show disabling of debuggee's virtual address space randomization."), _("\
-When this mode is on (which is the default), randomization of the virtual\n\
-address space is disabled. Standalone programs run with the randomization\n\
-enabled by default on some platforms."),
- &set_disable_randomization,
- &show_disable_randomization,
- &setlist, &showlist);
}
\f
projects / deliverable / binutils-gdb.git / blobdiff