glibc/sysdeps/unix/sysv/linux/sigtimedwait.c
Adhemerval Zanella 8b0e795aaa Simplify Linux sig{timed}wait{info} implementations
This patch simplifies sig{timed}wait{info} by:

  - Assuming __NR_rt_sigtimedwait existence on all architectures due minimum
    kernel version requirement (it pre-dates Linux git inclusion for Linux
    2.6.12).

  - Call __sigtimedwait on both sigwait and sigwaitinfo.

  - Now that sigwait is based on an internal sigtimedwait call and it is
    present of both libc.so and libpthread.so we need to add an external
    private definition of __sigtimedwait for libpthread.so call.

Checked on x86_64-linux-gnu.

	* sysdeps/unix/sysv/linux/Versions (libc) [GLIBC_PRIVATE]: Add
	__sigtimedwait.
	* sysdeps/unix/sysv/linux/sigtimedwait.c: Simplify includes and
	assume __NR_rt_sigtimedwait.
	* sysdeps/unix/sysv/linux/sigwait.c (__sigwait): Call __sigtimedwait
	and add LIBC_CANCEL_HANDLED for cancellation marking.
	* sysdeps/unix/sysv/linux/sigwaitinfo.c (__sigwaitinfo): Likewise.

Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Zack Weinberg <zackw@panix.com>
2017-11-06 17:37:57 -02:00

55 lines
2.0 KiB
C

/* Copyright (C) 1997-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <signal.h>
#include <string.h>
#include <sysdep-cancel.h>
int
__sigtimedwait (const sigset_t *set, siginfo_t *info,
const struct timespec *timeout)
{
sigset_t tmpset;
if (set != NULL
&& (__builtin_expect (__sigismember (set, SIGCANCEL), 0)
|| __builtin_expect (__sigismember (set, SIGSETXID), 0)))
{
/* Create a temporary mask without the bit for SIGCANCEL set. */
// We are not copying more than we have to.
memcpy (&tmpset, set, _NSIG / 8);
__sigdelset (&tmpset, SIGCANCEL);
__sigdelset (&tmpset, SIGSETXID);
set = &tmpset;
}
/* XXX The size argument hopefully will have to be changed to the
real size of the user-level sigset_t. */
int result = SYSCALL_CANCEL (rt_sigtimedwait, set, info, timeout, _NSIG / 8);
/* The kernel generates a SI_TKILL code in si_code in case tkill is
used. tkill is transparently used in raise(). Since having
SI_TKILL as a code is useful in general we fold the results
here. */
if (result != -1 && info != NULL && info->si_code == SI_TKILL)
info->si_code = SI_USER;
return result;
}
libc_hidden_def (__sigtimedwait)
weak_alias (__sigtimedwait, sigtimedwait)