/* Handle real-time signal allocation. Copyright (C) 1997, 1998, 1999 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ #include <features.h> #include <signal.h> #include <sys/types.h> #include <sys/syscall.h> /* Only enable rt signals when it is supported at compile time */ #ifndef __NR_rt_sigaction /* In these variables we keep track of the used variables. If the platform does not support any real-time signals we will define the values to some unreasonable value which will signal failing of all the functions below. */ static int current_rtmin = -1; static int current_rtmax = -1; #else # ifdef __UCLIBC_HAS_THREADS_NATIVE__ static int current_rtmin = __SIGRTMIN + 2; # else static int current_rtmin = __SIGRTMIN; # endif static int current_rtmax = __SIGRTMAX; #endif /* Return number of available real-time signal with highest priority. */ int __libc_current_sigrtmin (void) { return current_rtmin; } /* Return number of available real-time signal with lowest priority. */ int __libc_current_sigrtmax (void) { return current_rtmax; } /* Allocate real-time signal with highest/lowest available priority. Please note that we don't use a lock since we assume this function to be called at program start. */ int __libc_allocate_rtsig (int high); int __libc_allocate_rtsig (int high) { if (current_rtmin == -1 || current_rtmin > current_rtmax) /* We don't have anymore signal available. */ return -1; return high ? current_rtmin++ : current_rtmax--; }