mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-22 13:00:06 +00:00
a6c813d0ad
It consolidates the tgkill call and it is the first step of making
pthread_cancel async-signal-safe. It also fix a possible issue
where the 'struct pthread' tid is not read atomically, which might
send an invalid cancellation signal (similar to what
db988e50a8 fixed for pthread_join).
Checked on x86_64-linux-gnu and aarch64-linux-gnu.
74 lines
2.4 KiB
C
74 lines
2.4 KiB
C
/* Send a signal to a specific pthread. Stub version.
|
|
Copyright (C) 2014-2021 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
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <unistd.h>
|
|
#include <pthreadP.h>
|
|
#include <shlib-compat.h>
|
|
|
|
int
|
|
__pthread_kill_internal (pthread_t threadid, int signo)
|
|
{
|
|
pid_t tid;
|
|
struct pthread *pd = (struct pthread *) threadid;
|
|
|
|
if (pd == THREAD_SELF)
|
|
/* It is a special case to handle raise() implementation after a vfork
|
|
call (which does not update the PD tid field). */
|
|
tid = INLINE_SYSCALL_CALL (gettid);
|
|
else
|
|
/* Force load of pd->tid into local variable or register. Otherwise
|
|
if a thread exits between ESRCH test and tgkill, we might return
|
|
EINVAL, because pd->tid would be cleared by the kernel. */
|
|
tid = atomic_forced_read (pd->tid);
|
|
|
|
int val;
|
|
if (__glibc_likely (tid > 0))
|
|
{
|
|
pid_t pid = __getpid ();
|
|
|
|
val = INTERNAL_SYSCALL_CALL (tgkill, pid, tid, signo);
|
|
val = (INTERNAL_SYSCALL_ERROR_P (val)
|
|
? INTERNAL_SYSCALL_ERRNO (val) : 0);
|
|
}
|
|
else
|
|
val = ESRCH;
|
|
|
|
return val;
|
|
}
|
|
|
|
int
|
|
__pthread_kill (pthread_t threadid, int signo)
|
|
{
|
|
/* Disallow sending the signal we use for cancellation, timers,
|
|
for the setxid implementation. */
|
|
if (__is_internal_signal (signo))
|
|
return EINVAL;
|
|
|
|
return __pthread_kill_internal (threadid, signo);
|
|
}
|
|
/* Some architectures (for instance arm) might pull raise through libgcc, so
|
|
avoid the symbol version if it ends up being used on ld.so. */
|
|
#if !IS_IN(rtld)
|
|
libc_hidden_def (__pthread_kill)
|
|
versioned_symbol (libc, __pthread_kill, pthread_kill, GLIBC_2_34);
|
|
|
|
# if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_34)
|
|
compat_symbol (libc, __pthread_kill, pthread_kill, GLIBC_2_0);
|
|
# endif
|
|
#endif
|