sysdeps/unix/sysv/linux/allocrtsig.c

   1 /* Copyright (C) 2002-2014 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
   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, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <signal.h>
  20
  21
  22 static int current_rtmin = __SIGRTMIN + 2;
  23 static int current_rtmax = __SIGRTMAX;
  24
  25
  26 /* We reserve __SIGRTMIN for use as the cancelation signal.  This
  27    signal is used internally.  */
  28 int
  29 __libc_current_sigrtmin (void)
  30 {
  31   return current_rtmin;
  32 }
  33 libc_hidden_def (__libc_current_sigrtmin)
  34 strong_alias (__libc_current_sigrtmin, __libc_current_sigrtmin_private)
  35
  36
  37 int
  38 __libc_current_sigrtmax (void)
  39 {
  40   return current_rtmax;
  41 }
  42 libc_hidden_def (__libc_current_sigrtmax)
  43 strong_alias (__libc_current_sigrtmax, __libc_current_sigrtmax_private)
  44
  45
  46 int
  47 __libc_allocate_rtsig (int high)
  48 {
  49   if (current_rtmin == -1 || current_rtmin > current_rtmax)
  50     /* We don't have anymore signal available.  */
  51     return -1;
  52
  53   return high ? current_rtmin++ : current_rtmax--;
  54 }
  55 strong_alias (__libc_allocate_rtsig, __libc_allocate_rtsig_private)