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Diffstat (limited to 'signal/allocrtsig.c')
-rw-r--r-- | signal/allocrtsig.c | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/signal/allocrtsig.c b/signal/allocrtsig.c new file mode 100644 index 0000000000..678bc8b17b --- /dev/null +++ b/signal/allocrtsig.c @@ -0,0 +1,89 @@ +/* Handle real-time signal allocation. + Copyright (C) 1997 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 Library General Public License as + published by the Free Software Foundation; either version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <signal.h> + +/* 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. */ +#ifndef __SIGRTMIN +static int current_rtmin = -1; +static int current_rtmax = -1; +#else +static int current_rtmin = __SIGRTMIN; +static int current_rtmax = __SIGRTMAX; + +static int initialized; + +#include "testrtsig.h" + +static void +init (void) +{ + if (!kernel_has_rtsig ()) + { + current_rtmin = -1; + current_rtmax = -1; + } + initialized = 1; +} +#endif + +/* Return number of available real-time signal with highest priority. */ +int +__libc_current_sigrtmin (void) +{ +#ifdef __SIGRTMIN + if (!initialized) + init (); +#endif + return current_rtmin; +} + +/* Return number of available real-time signal with lowest priority. */ +int +__libc_current_sigrtmax (void) +{ +#ifdef __SIGRTMIN + if (!initialized) + init (); +#endif + 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) +{ +#ifndef __SIGRTMIN + return -1; +#else + if (!initialized) + init (); + if (current_rtmin != -1 || current_rtmin > current_rtmax) + /* We don't have anymore signal available. */ + return -1; + + return high ? current_rtmin++ : current_rtmax--; +#endif +} |