| /* Handle real-time signal allocation. Generic version. |
| Copyright (C) 1997-2018 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, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <signal.h> |
| |
| /* Another sysdeps file can #define this and then #include this file. */ |
| #ifndef RESERVED_SIGRT |
| # define RESERVED_SIGRT 0 |
| #endif |
| |
| /* 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. */ |
| #ifdef __SIGRTMIN |
| static int current_rtmin = __SIGRTMIN + RESERVED_SIGRT; |
| static int current_rtmax = __SIGRTMAX; |
| #endif |
| |
| /* Return number of available real-time signal with highest priority. */ |
| int |
| __libc_current_sigrtmin (void) |
| { |
| #ifdef __SIGRTMIN |
| return current_rtmin; |
| #else |
| return -1; |
| #endif |
| } |
| libc_hidden_def (__libc_current_sigrtmin) |
| strong_alias (__libc_current_sigrtmin, __libc_current_sigrtmin_private) |
| |
| /* Return number of available real-time signal with lowest priority. */ |
| int |
| __libc_current_sigrtmax (void) |
| { |
| #ifdef __SIGRTMIN |
| return current_rtmax; |
| #else |
| return -1; |
| #endif |
| } |
| libc_hidden_def (__libc_current_sigrtmax) |
| strong_alias (__libc_current_sigrtmax, __libc_current_sigrtmax_private) |
| |
| /* 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) |
| { |
| #ifndef __SIGRTMIN |
| return -1; |
| #else |
| if (current_rtmin == -1 || current_rtmin > current_rtmax) |
| /* We don't have any more signals available. */ |
| return -1; |
| |
| return high ? current_rtmin++ : current_rtmax--; |
| #endif |
| } |
| strong_alias (__libc_allocate_rtsig, __libc_allocate_rtsig_private) |