From bfdb73e145e6ca3bedcd5ef93e0b5d0fe9498645 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Fri, 12 Jun 2009 08:34:02 -0700 Subject: Implement pthread_sigqueue. The kernel from 2.3.31 on supports the rt_tgsigqueueinfo syscall. Use it to implement the non-standard extension which, like sigqueue, can pass additional data to the receiving thread. --- nptl/sysdeps/unix/sysv/linux/pthread_sigqueue.c | 83 +++++++++++++++++++++++++ 1 file changed, 83 insertions(+) create mode 100644 nptl/sysdeps/unix/sysv/linux/pthread_sigqueue.c (limited to 'nptl/sysdeps/unix/sysv/linux') diff --git a/nptl/sysdeps/unix/sysv/linux/pthread_sigqueue.c b/nptl/sysdeps/unix/sysv/linux/pthread_sigqueue.c new file mode 100644 index 0000000000..4440703b6a --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/pthread_sigqueue.c @@ -0,0 +1,83 @@ +/* Copyright (C) 2009 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper , 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include +#include +#include +#include +#include +#include +#include +#include + + +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 (__builtin_expect (tid <= 0, 0)) + /* Not a valid thread handle. */ + return ESRCH; + + /* Disallow sending the signal we use for cancellation, timers, for + 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 +} -- cgit v1.2.3-70-g09d2