/* GNU/Linux native-dependent code common to multiple platforms.
- Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007
Free Software Foundation, Inc.
This file is part of GDB.
struct simple_pid_list
{
int pid;
+ int status;
struct simple_pid_list *next;
};
struct simple_pid_list *stopped_pids;
/* Trivial list manipulation functions to keep track of a list of
new stopped processes. */
static void
-add_to_pid_list (struct simple_pid_list **listp, int pid)
+add_to_pid_list (struct simple_pid_list **listp, int pid, int status)
{
struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list));
new_pid->pid = pid;
+ new_pid->status = status;
new_pid->next = *listp;
*listp = new_pid;
}
static int
-pull_pid_from_list (struct simple_pid_list **listp, int pid)
+pull_pid_from_list (struct simple_pid_list **listp, int pid, int *status)
{
struct simple_pid_list **p;
if ((*p)->pid == pid)
{
struct simple_pid_list *next = (*p)->next;
+ *status = (*p)->status;
xfree (*p);
*p = next;
return 1;
return 0;
}
-void
-linux_record_stopped_pid (int pid)
+static void
+linux_record_stopped_pid (int pid, int status)
{
- add_to_pid_list (&stopped_pids, pid);
+ add_to_pid_list (&stopped_pids, pid, status);
}
\f
return 0;
}
-ptid_t
-linux_handle_extended_wait (int pid, int status,
- struct target_waitstatus *ourstatus)
-{
- int event = status >> 16;
-
- if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK
- || event == PTRACE_EVENT_CLONE)
- {
- unsigned long new_pid;
- int ret;
-
- ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid);
-
- /* If we haven't already seen the new PID stop, wait for it now. */
- if (! pull_pid_from_list (&stopped_pids, new_pid))
- {
- /* The new child has a pending SIGSTOP. We can't affect it until it
- hits the SIGSTOP, but we're already attached. */
- ret = my_waitpid (new_pid, &status,
- (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0);
- if (ret == -1)
- perror_with_name (_("waiting for new child"));
- else if (ret != new_pid)
- internal_error (__FILE__, __LINE__,
- _("wait returned unexpected PID %d"), ret);
- else if (!WIFSTOPPED (status) || WSTOPSIG (status) != SIGSTOP)
- internal_error (__FILE__, __LINE__,
- _("wait returned unexpected status 0x%x"), status);
- }
-
- if (event == PTRACE_EVENT_FORK)
- ourstatus->kind = TARGET_WAITKIND_FORKED;
- else if (event == PTRACE_EVENT_VFORK)
- ourstatus->kind = TARGET_WAITKIND_VFORKED;
- else
- ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
-
- ourstatus->value.related_pid = new_pid;
- return inferior_ptid;
- }
-
- if (event == PTRACE_EVENT_EXEC)
- {
- ourstatus->kind = TARGET_WAITKIND_EXECD;
- ourstatus->value.execd_pathname
- = xstrdup (child_pid_to_exec_file (pid));
-
- if (linux_parent_pid)
- {
- detach_breakpoints (linux_parent_pid);
- ptrace (PTRACE_DETACH, linux_parent_pid, 0, 0);
-
- linux_parent_pid = 0;
- }
-
- return inferior_ptid;
- }
-
- internal_error (__FILE__, __LINE__,
- _("unknown ptrace event %d"), event);
-}
-
\f
void
child_insert_fork_catchpoint (int pid)
return kill (lwpid, signo);
}
-/* Handle a GNU/Linux extended wait response. Most of the work we
- just pass off to linux_handle_extended_wait, but if it reports a
- clone event we need to add the new LWP to our list (and not report
- the trap to higher layers). This function returns non-zero if
- the event should be ignored and we should wait again. If STOPPING
- is true, the new LWP remains stopped, otherwise it is continued. */
+/* Handle a GNU/Linux extended wait response. If we see a clone
+ event, we need to add the new LWP to our list (and not report the
+ trap to higher layers). This function returns non-zero if the
+ event should be ignored and we should wait again. If STOPPING is
+ true, the new LWP remains stopped, otherwise it is continued. */
static int
-linux_nat_handle_extended (struct lwp_info *lp, int status, int stopping)
+linux_handle_extended_wait (struct lwp_info *lp, int status,
+ int stopping)
{
- linux_handle_extended_wait (GET_LWP (lp->ptid), status,
- &lp->waitstatus);
+ int pid = GET_LWP (lp->ptid);
+ struct target_waitstatus *ourstatus = &lp->waitstatus;
+ struct lwp_info *new_lp = NULL;
+ int event = status >> 16;
- /* TARGET_WAITKIND_SPURIOUS is used to indicate clone events. */
- if (lp->waitstatus.kind == TARGET_WAITKIND_SPURIOUS)
+ if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK
+ || event == PTRACE_EVENT_CLONE)
{
- struct lwp_info *new_lp;
- new_lp = add_lwp (BUILD_LWP (lp->waitstatus.value.related_pid,
- GET_PID (inferior_ptid)));
- new_lp->cloned = 1;
+ unsigned long new_pid;
+ int ret;
+
+ ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid);
- if (stopping)
- new_lp->stopped = 1;
+ /* If we haven't already seen the new PID stop, wait for it now. */
+ if (! pull_pid_from_list (&stopped_pids, new_pid, &status))
+ {
+ /* The new child has a pending SIGSTOP. We can't affect it until it
+ hits the SIGSTOP, but we're already attached. */
+ ret = my_waitpid (new_pid, &status,
+ (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0);
+ if (ret == -1)
+ perror_with_name (_("waiting for new child"));
+ else if (ret != new_pid)
+ internal_error (__FILE__, __LINE__,
+ _("wait returned unexpected PID %d"), ret);
+ else if (!WIFSTOPPED (status))
+ internal_error (__FILE__, __LINE__,
+ _("wait returned unexpected status 0x%x"), status);
+ }
+
+ ourstatus->value.related_pid = new_pid;
+
+ if (event == PTRACE_EVENT_FORK)
+ ourstatus->kind = TARGET_WAITKIND_FORKED;
+ else if (event == PTRACE_EVENT_VFORK)
+ ourstatus->kind = TARGET_WAITKIND_VFORKED;
else
- ptrace (PTRACE_CONT, lp->waitstatus.value.related_pid, 0, 0);
+ {
+ ourstatus->kind = TARGET_WAITKIND_IGNORE;
+ new_lp = add_lwp (BUILD_LWP (new_pid, GET_PID (inferior_ptid)));
+ new_lp->cloned = 1;
- lp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
+ if (WSTOPSIG (status) != SIGSTOP)
+ {
+ /* This can happen if someone starts sending signals to
+ the new thread before it gets a chance to run, which
+ have a lower number than SIGSTOP (e.g. SIGUSR1).
+ This is an unlikely case, and harder to handle for
+ fork / vfork than for clone, so we do not try - but
+ we handle it for clone events here. We'll send
+ the other signal on to the thread below. */
+
+ new_lp->signalled = 1;
+ }
+ else
+ status = 0;
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLHE: Got clone event from LWP %ld, resuming\n",
- GET_LWP (lp->ptid));
- ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
+ if (stopping)
+ new_lp->stopped = 1;
+ else
+ {
+ new_lp->resumed = 1;
+ ptrace (PTRACE_CONT, lp->waitstatus.value.related_pid, 0,
+ status ? WSTOPSIG (status) : 0);
+ }
- return 1;
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LHEW: Got clone event from LWP %ld, resuming\n",
+ GET_LWP (lp->ptid));
+ ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
+
+ return 1;
+ }
+
+ return 0;
}
- return 0;
+ if (event == PTRACE_EVENT_EXEC)
+ {
+ ourstatus->kind = TARGET_WAITKIND_EXECD;
+ ourstatus->value.execd_pathname
+ = xstrdup (child_pid_to_exec_file (pid));
+
+ if (linux_parent_pid)
+ {
+ detach_breakpoints (linux_parent_pid);
+ ptrace (PTRACE_DETACH, linux_parent_pid, 0, 0);
+
+ linux_parent_pid = 0;
+ }
+
+ return 0;
+ }
+
+ internal_error (__FILE__, __LINE__,
+ _("unknown ptrace event %d"), event);
}
/* Wait for LP to stop. Returns the wait status, or 0 if the LWP has
fprintf_unfiltered (gdb_stdlog,
"WL: Handling extended status 0x%06x\n",
status);
- if (linux_nat_handle_extended (lp, status, 1))
+ if (linux_handle_extended_wait (lp, status, 1))
return wait_lwp (lp);
}
lp->status = 0;
}
- while (linux_nat_has_pending (GET_LWP (lp->ptid), &pending, flush_mask))
+ /* While there is a pending signal we would like to flush, continue
+ the inferior and collect another signal. But if there's already
+ a saved status that we don't want to flush, we can't resume the
+ inferior - if it stopped for some other reason we wouldn't have
+ anywhere to save the new status. In that case, we must leave the
+ signal unflushed (and possibly generate an extra SIGINT stop).
+ That's much less bad than losing a signal. */
+ while (lp->status == 0
+ && linux_nat_has_pending (GET_LWP (lp->ptid), &pending, flush_mask))
{
int ret;
from waitpid before or after the event is. */
if (WIFSTOPPED (status) && !lp)
{
- linux_record_stopped_pid (lwpid);
+ linux_record_stopped_pid (lwpid, status);
status = 0;
continue;
}
fprintf_unfiltered (gdb_stdlog,
"LLW: Handling extended status 0x%06x\n",
status);
- if (linux_nat_handle_extended (lp, status, 0))
+ if (linux_handle_extended_wait (lp, status, 0))
{
status = 0;
continue;
size, paddr_nz (addr),
read ? 'r' : ' ',
write ? 'w' : ' ', exec ? 'x' : ' ');
- if (filename && filename[0])
+ if (filename[0])
fprintf_filtered (gdb_stdout, " for %s", filename);
fprintf_filtered (gdb_stdout, "\n");
}
projects / deliverable / binutils-gdb.git / blobdiff