sysdeps/posix/sigpause.c

   1 /* Copyright (C) 1991,92,94-98,2000,2002,2003,2004
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #define sigpause __rename_sigpause
  21 #include <errno.h>
  22 #include <signal.h>
  23 #include <stddef.h>             /* For NULL.  */
  24 #include <sysdep-cancel.h>
  25 #undef sigpause
  26
  27 #include <sigset-cvt-mask.h>
  28
  29 /* Set the mask of blocked signals to MASK,
  30    wait for a signal to arrive, and then restore the mask.  */
  31 static int
  32 do_sigpause (int sig_or_mask, int is_sig)
  33 {
  34   sigset_t set;
  35
  36   if (is_sig != 0)
  37     {
  38       /* The modern X/Open implementation is requested.  */
  39       if (__sigprocmask (0, NULL, &set) < 0
  40           || sigdelset (&set, sig_or_mask) < 0)
  41         return -1;
  42     }
  43   else if (sigset_set_old_mask (&set, sig_or_mask) < 0)
  44     return -1;
  45
  46   /* Note the sigpause() is a cancellation point.  But since we call
  47      sigsuspend() which itself is a cancellation point we do not have
  48      to do anything here.  */
  49   return __sigsuspend (&set);
  50 }
  51
  52 int
  53 __sigpause (int sig_or_mask, int is_sig)
  54 {
  55   if (SINGLE_THREAD_P)
  56     return do_sigpause (sig_or_mask, is_sig);
  57
  58   int oldtype = LIBC_CANCEL_ASYNC ();
  59
  60   int result = do_sigpause (sig_or_mask, is_sig);
  61
  62   LIBC_CANCEL_RESET (oldtype);
  63
  64   return result;
  65 }
  66 libc_hidden_def (__sigpause)
  67
  68 /* We have to provide a default version of this function since the
  69    standards demand it.  The version which is a bit more reasonable is
  70    the BSD version.  So make this the default.  */
  71 int
  72 __attribute__ ((weak))
  73 __default_sigpause (int mask)
  74 {
  75   return __sigpause (mask, 0);
  76 }
  77 #undef sigpause
  78 weak_alias (__default_sigpause, sigpause)
  79 strong_alias (__default_sigpause, __libc_sigpause)
  80
  81
  82 /* We have to provide a default version of this function since the
  83    standards demand it.  The version which is a bit more reasonable is
  84    the BSD version.  So make this the default.  */
  85 int
  86 __attribute__ ((weak))
  87 __xpg_sigpause (int sig)
  88 {
  89   return __sigpause (sig, 1);
  90 }
  91 strong_alias (__xpg_sigpause, __libc___xpg_sigpause)