usr/src/lib/libast/common/comp/sigunblock.c

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  12 *                                                                      *
  13 *              Information and Software Systems Research               *
  14 *                            AT&T Research                             *
  15 *                           Florham Park NJ                            *
  16 *                                                                      *
  17 *                 Glenn Fowler <gsf@research.att.com>                  *
  18 *                  David Korn <dgk@research.att.com>                   *
  19 *                   Phong Vo <kpv@research.att.com>                    *
  20 *                                                                      *
  21 ***********************************************************************/
  22 #pragma prototyped
  23
  24 #include <ast.h>
  25
  26 #if _lib_sigunblock
  27
  28 NoN(sigunblock)
  29
  30 #else
  31
  32 #include <sig.h>
  33
  34 #ifndef SIG_UNBLOCK
  35 #undef  _lib_sigprocmask
  36 #endif
  37
  38 int
  39 sigunblock(int s)
  40 {
  41 #if _lib_sigprocmask
  42         int             op;
  43         sigset_t        mask;
  44
  45         sigemptyset(&mask);
  46         if (s)
  47         {
  48                 sigaddset(&mask, s);
  49                 op = SIG_UNBLOCK;
  50         }
  51         else op = SIG_SETMASK;
  52         return(sigprocmask(op, &mask, NiL));
  53 #else
  54 #if _lib_sigsetmask
  55         return(sigsetmask(s ? (sigsetmask(0L) & ~sigmask(s)) : 0L));
  56 #else
  57         NoP(s);
  58         return(0);
  59 #endif
  60 #endif
  61 }
  62
  63 #endif