1 /* Copyright (C) 2009 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@redhat.com>, 2009.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
18
19 #include <errno.h>
20 #include <signal.h>
21 #include <string.h>
22 #include <unistd.h>
23 #include <pthreadP.h>
24 #include <tls.h>
25 #include <sysdep.h>
26 #include <bits/kernel-features.h>
27
28
29 int
pthread_sigqueue(pthread_t threadid,int signo,const union sigval value)30 pthread_sigqueue (
31 pthread_t threadid,
32 int signo,
33 const union sigval value)
34 {
35 #ifdef __NR_rt_tgsigqueueinfo
36 struct pthread *pd = (struct pthread *) threadid;
37
38 /* Make sure the descriptor is valid. */
39 if (DEBUGGING_P && INVALID_TD_P (pd))
40 /* Not a valid thread handle. */
41 return ESRCH;
42
43 /* Force load of pd->tid into local variable or register. Otherwise
44 if a thread exits between ESRCH test and tgkill, we might return
45 EINVAL, because pd->tid would be cleared by the kernel. */
46 pid_t tid = atomic_forced_read (pd->tid);
47 if (__builtin_expect (tid <= 0, 0))
48 /* Not a valid thread handle. */
49 return ESRCH;
50
51 /* Disallow sending the signal we use for cancellation, timers, for
52 for the setxid implementation. */
53 if (signo == SIGCANCEL || signo == SIGTIMER || signo == SIGSETXID)
54 return EINVAL;
55
56 pid_t pid = getpid ();
57
58 /* Set up the siginfo_t structure. */
59 siginfo_t info;
60 memset (&info, '\0', sizeof (siginfo_t));
61 info.si_signo = signo;
62 info.si_code = SI_QUEUE;
63 info.si_pid = pid;
64 info.si_uid = getuid ();
65 info.si_value = value;
66
67 /* We have a special syscall to do the work. */
68 INTERNAL_SYSCALL_DECL (err);
69
70 int val = INTERNAL_SYSCALL (rt_tgsigqueueinfo, err, 4,
71 pid, tid, signo, &info);
72
73 return (INTERNAL_SYSCALL_ERROR_P (val, err)
74 ? INTERNAL_SYSCALL_ERRNO (val, err) : 0);
75 #else
76 return ENOSYS;
77 #endif
78 }
79