2fa0369e51
Just a small optimization. No need to block/unblock signals if we're not going to call sigsuspend. gdb/ 2014-02-27 Pedro Alves <palves@redhat.com> * nat/linux-waitpid.c (my_waitpid): Only block signals if WNOHANG isn't set.
152 lines
3.6 KiB
C
152 lines
3.6 KiB
C
/* Wrapper implementation for waitpid for GNU/Linux (LWP layer).
|
|
|
|
Copyright (C) 2001-2014 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 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
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, see <http://www.gnu.org/licenses/>. */
|
|
|
|
#ifdef GDBSERVER
|
|
#include "server.h"
|
|
#else
|
|
#include "defs.h"
|
|
#include "signal.h"
|
|
#endif
|
|
|
|
#include "nat/linux-nat.h"
|
|
#include "nat/linux-waitpid.h"
|
|
#include "gdb_wait.h"
|
|
|
|
#include <string.h>
|
|
|
|
/* Print debugging output based on the format string FORMAT and
|
|
its parameters. */
|
|
|
|
static inline void
|
|
linux_debug (const char *format, ...)
|
|
{
|
|
#ifdef GDBSERVER
|
|
if (debug_threads)
|
|
{
|
|
va_list args;
|
|
va_start (args, format);
|
|
vfprintf (stderr, format, args);
|
|
va_end (args);
|
|
}
|
|
#else
|
|
/* GDB-specific debugging output. */
|
|
#endif
|
|
}
|
|
|
|
/* Convert wait status STATUS to a string. Used for printing debug
|
|
messages only. */
|
|
|
|
char *
|
|
status_to_str (int status)
|
|
{
|
|
static char buf[64];
|
|
|
|
if (WIFSTOPPED (status))
|
|
{
|
|
if (WSTOPSIG (status) == SYSCALL_SIGTRAP)
|
|
snprintf (buf, sizeof (buf), "%s (stopped at syscall)",
|
|
strsignal (SIGTRAP));
|
|
else
|
|
snprintf (buf, sizeof (buf), "%s (stopped)",
|
|
strsignal (WSTOPSIG (status)));
|
|
}
|
|
else if (WIFSIGNALED (status))
|
|
snprintf (buf, sizeof (buf), "%s (terminated)",
|
|
strsignal (WTERMSIG (status)));
|
|
else
|
|
snprintf (buf, sizeof (buf), "%d (exited)", WEXITSTATUS (status));
|
|
|
|
return buf;
|
|
}
|
|
|
|
/* Wrapper function for waitpid which handles EINTR, and emulates
|
|
__WALL for systems where that is not available. */
|
|
|
|
int
|
|
my_waitpid (int pid, int *status, int flags)
|
|
{
|
|
int ret, out_errno;
|
|
|
|
linux_debug ("my_waitpid (%d, 0x%x)\n", pid, flags);
|
|
|
|
if (flags & __WALL)
|
|
{
|
|
sigset_t block_mask, org_mask, wake_mask;
|
|
int wnohang;
|
|
|
|
wnohang = (flags & WNOHANG) != 0;
|
|
flags &= ~(__WALL | __WCLONE);
|
|
|
|
if (!wnohang)
|
|
{
|
|
flags |= WNOHANG;
|
|
|
|
/* Block all signals while here. This avoids knowing about
|
|
LinuxThread's signals. */
|
|
sigfillset (&block_mask);
|
|
sigprocmask (SIG_BLOCK, &block_mask, &org_mask);
|
|
|
|
/* ... except during the sigsuspend below. */
|
|
sigemptyset (&wake_mask);
|
|
}
|
|
|
|
while (1)
|
|
{
|
|
/* Since all signals are blocked, there's no need to check
|
|
for EINTR here. */
|
|
ret = waitpid (pid, status, flags);
|
|
out_errno = errno;
|
|
|
|
if (ret == -1 && out_errno != ECHILD)
|
|
break;
|
|
else if (ret > 0)
|
|
break;
|
|
|
|
if (flags & __WCLONE)
|
|
{
|
|
/* We've tried both flavors now. If WNOHANG is set,
|
|
there's nothing else to do, just bail out. */
|
|
if (wnohang)
|
|
break;
|
|
|
|
linux_debug ("blocking\n");
|
|
|
|
/* Block waiting for signals. */
|
|
sigsuspend (&wake_mask);
|
|
}
|
|
flags ^= __WCLONE;
|
|
}
|
|
|
|
if (!wnohang)
|
|
sigprocmask (SIG_SETMASK, &org_mask, NULL);
|
|
}
|
|
else
|
|
{
|
|
do
|
|
ret = waitpid (pid, status, flags);
|
|
while (ret == -1 && errno == EINTR);
|
|
out_errno = errno;
|
|
}
|
|
|
|
linux_debug ("my_waitpid (%d, 0x%x): status(%x), %d\n",
|
|
pid, flags, status ? *status : -1, ret);
|
|
|
|
errno = out_errno;
|
|
return ret;
|
|
}
|