lib/libc_r/uthread/uthread_sigmask.c

   1 /*
   2  * Copyright (c) 1997 John Birrell <jb@cimlogic.com.au>.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by John Birrell.
  16  * 4. Neither the name of the author nor the names of any co-contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  * $FreeBSD: src/lib/libc_r/uthread/uthread_sigmask.c,v 1.5.2.3 2002/10/22 14:44:03 fjoe Exp $
  33  * $DragonFly: src/lib/libc_r/uthread/uthread_sigmask.c,v 1.3 2005/05/30 20:50:53 joerg Exp $
  34  */
  35 #include <sys/param.h>
  36 #include <sys/types.h>
  37 #include <sys/signalvar.h>
  38 #include <errno.h>
  39 #include <signal.h>
  40 #include <pthread.h>
  41 #include "pthread_private.h"
  42
  43 int
  44 _pthread_sigmask(int how, const sigset_t *set, sigset_t *oset)
  45 {
  46         struct pthread  *curthread = _get_curthread();
  47         sigset_t        sigset;
  48         int             ret = 0;
  49
  50         /* Check if the existing signal process mask is to be returned: */
  51         if (oset != NULL) {
  52                 /* Return the current mask: */
  53                 *oset = curthread->sigmask;
  54         }
  55         /* Check if a new signal set was provided by the caller: */
  56         if (set != NULL) {
  57                 /* Process according to what to do: */
  58                 switch (how) {
  59                 /* Block signals: */
  60                 case SIG_BLOCK:
  61                         /* Add signals to the existing mask: */
  62                         SIGSETOR(curthread->sigmask, *set);
  63                         break;
  64
  65                 /* Unblock signals: */
  66                 case SIG_UNBLOCK:
  67                         /* Clear signals from the existing mask: */
  68                         SIGSETNAND(curthread->sigmask, *set);
  69                         break;
  70
  71                 /* Set the signal process mask: */
  72                 case SIG_SETMASK:
  73                         /* Set the new mask: */
  74                         curthread->sigmask = *set;
  75                         break;
  76
  77                 /* Trap invalid actions: */
  78                 default:
  79                         /* Return an invalid argument: */
  80                         errno = EINVAL;
  81                         ret = -1;
  82                         break;
  83                 }
  84
  85                 /* Increment the sequence number: */
  86                 curthread->sigmask_seqno++;
  87
  88                 /*
  89                  * Check if there are pending signals for the running
  90                  * thread or process that aren't blocked:
  91                  */
  92                 sigset = curthread->sigpend;
  93                 SIGSETOR(sigset, _process_sigpending);
  94                 SIGSETNAND(sigset, curthread->sigmask);
  95                 if (SIGNOTEMPTY(sigset))
  96                         /*
  97                          * Call the kernel scheduler which will safely
  98                          * install a signal frame for the running thread:
  99                          */
 100                         _thread_kern_sched_sig();
 101         }
 102
 103         /* Return the completion status: */
 104         return (ret);
 105 }
 106
 107 __strong_reference(_pthread_sigmask, pthread_sigmask);