diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/pthread_sigqueue.c')
-rw-r--r-- | sysdeps/unix/sysv/linux/pthread_sigqueue.c | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/pthread_sigqueue.c b/sysdeps/unix/sysv/linux/pthread_sigqueue.c new file mode 100644 index 0000000000..1e66815416 --- /dev/null +++ b/sysdeps/unix/sysv/linux/pthread_sigqueue.c @@ -0,0 +1,81 @@ +/* Copyright (C) 2009-2014 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@redhat.com>, 2009. + + 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 <unistd.h> +#include <pthreadP.h> +#include <tls.h> +#include <sysdep.h> + + +int +pthread_sigqueue (threadid, signo, value) + pthread_t threadid; + int signo; + const union sigval value; +{ +#ifdef __NR_rt_tgsigqueueinfo + struct pthread *pd = (struct pthread *) threadid; + + /* Make sure the descriptor is valid. */ + if (DEBUGGING_P && INVALID_TD_P (pd)) + /* Not a valid thread handle. */ + return ESRCH; + + /* 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. */ + pid_t tid = atomic_forced_read (pd->tid); + if (__glibc_unlikely (tid <= 0)) + /* Not a valid thread handle. */ + return ESRCH; + + /* Disallow sending the signal we use for cancellation, timers, + for the setxid implementation. */ + if (signo == SIGCANCEL || signo == SIGTIMER || signo == SIGSETXID) + return EINVAL; + + /* Set up the siginfo_t structure. */ + siginfo_t info; + memset (&info, '\0', sizeof (siginfo_t)); + info.si_signo = signo; + info.si_code = SI_QUEUE; + info.si_pid = THREAD_GETMEM (THREAD_SELF, pid); + info.si_uid = getuid (); + info.si_value = value; + + /* We have a special syscall to do the work. */ + INTERNAL_SYSCALL_DECL (err); + + /* One comment: The PID field in the TCB can temporarily be changed + (in fork). But this must not affect this code here. Since this + function would have to be called while the thread is executing + fork, it would have to happen in a signal handler. But this is + no allowed, pthread_sigqueue is not guaranteed to be async-safe. */ + int val = INTERNAL_SYSCALL (rt_tgsigqueueinfo, err, 4, + THREAD_GETMEM (THREAD_SELF, pid), + tid, signo, &info); + + return (INTERNAL_SYSCALL_ERROR_P (val, err) + ? INTERNAL_SYSCALL_ERRNO (val, err) : 0); +#else + return ENOSYS; +#endif +} |