sysdeps/posix/sigpause.c

   1 /* Copyright (C) 1991,92,94-98,2000,2002,2003 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <errno.h>
  20 #include <signal.h>
  21 #include <stddef.h>             /* For NULL.  */
  22 #include <sysdep-cancel.h>
  23
  24 #include <sigset-cvt-mask.h>
  25
  26 /* Set the mask of blocked signals to MASK,
  27    wait for a signal to arrive, and then restore the mask.  */
  28 static int
  29 do_sigpause (int sig_or_mask, int is_sig)
  30 {
  31   sigset_t set;
  32
  33   if (is_sig != 0)
  34     {
  35       /* The modern X/Open implementation is requested.  */
  36       if (__sigprocmask (0, NULL, &set) < 0
  37           || sigdelset (&set, sig_or_mask) < 0)
  38         return -1;
  39     }
  40   else if (sigset_set_old_mask (&set, sig_or_mask) < 0)
  41     return -1;
  42
  43   /* Note the sigpause() is a cancellation point.  But since we call
  44      sigsuspend() which itself is a cancellation point we do not have
  45      to do anything here.  */
  46   return __sigsuspend (&set);
  47 }
  48
  49 int
  50 __sigpause (int sig_or_mask, int is_sig)
  51 {
  52   if (SINGLE_THREAD_P)
  53     return do_sigpause (sig_or_mask, is_sig);
  54
  55   int oldtype = LIBC_CANCEL_ASYNC ();
  56
  57   int result = do_sigpause (sig_or_mask, is_sig);
  58
  59   LIBC_CANCEL_RESET (oldtype);
  60
  61   return result;
  62 }
  63 libc_hidden_def (__sigpause)
  64
  65 /* We have to provide a default version of this function since the
  66    standards demand it.  The version which is a bit more reasonable is
  67    the BSD version.  So make this the default.  */
  68 int
  69 __attribute__ ((weak))
  70 __default_sigpause (int mask)
  71 {
  72   return __sigpause (mask, 0);
  73 }
  74 #undef sigpause
  75 weak_alias (__default_sigpause, sigpause)
  76 strong_alias (__default_sigpause, __libc_sigpause)
  77
  78
  79 /* We have to provide a default version of this function since the
  80    standards demand it.  The version which is a bit more reasonable is
  81    the BSD version.  So make this the default.  */
  82 int
  83 __attribute__ ((weak))
  84 __xpg_sigpause (int sig)
  85 {
  86   return __sigpause (sig, 1);
  87 }
  88 strong_alias (__xpg_sigpause, __libc___xpg_sigpause)