lib/libc/gen/signal.c

   1 /*      $NetBSD: signal.c,v 1.11 2000/01/22 22:19:12 mycroft Exp $      */
   2
   3 /*
   4  * Copyright (c) 1985, 1989, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #if defined(LIBC_SCCS) && !defined(lint)
  34 #if 0
  35 static char sccsid[] = "@(#)signal.c    8.1 (Berkeley) 6/4/93";
  36 #else
  37 __RCSID("$NetBSD: signal.c,v 1.11 2000/01/22 22:19:12 mycroft Exp $");
  38 #endif
  39 #endif /* LIBC_SCCS and not lint */
  40
  41 /*
  42  * Almost backwards compatible signal.
  43  */
  44 #include "namespace.h"
  45 #include <signal.h>
  46
  47 #ifdef __weak_alias
  48 __weak_alias(signal,_signal)
  49 #endif
  50
  51 sigset_t __sigintr;             /* shared with siginterrupt */
  52
  53 sig_t
  54 signal(s, a)
  55         int s;
  56         sig_t a;
  57 {
  58         struct sigaction sa, osa;
  59
  60         sa.sa_handler = a;
  61         sigemptyset(&sa.sa_mask);
  62         sa.sa_flags = 0;
  63         if (!sigismember(&__sigintr, s))
  64                 sa.sa_flags |= SA_RESTART;
  65         if (sigaction(s, &sa, &osa) < 0)
  66                 return (SIG_ERR);
  67         return (osa.sa_handler);
  68 }