support/xsignal.h

   1 /* Support functionality for using signals.
   2    Copyright (C) 2016-2020 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, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef SUPPORT_SIGNAL_H
  20 #define SUPPORT_SIGNAL_H
  21
  22 #include <signal.h>
  23 #include <sys/cdefs.h>
  24
  25 __BEGIN_DECLS
  26
  27 /* The following functions call the corresponding libc functions and
  28    terminate the process on error.  */
  29
  30 void xraise (int sig);
  31 sighandler_t xsignal (int sig, sighandler_t handler);
  32 void xsigaction (int sig, const struct sigaction *newact,
  33                  struct sigaction *oldact);
  34
  35 /* The following functions call the corresponding libpthread functions
  36    and terminate the process on error.  */
  37
  38 void xpthread_sigmask (int how, const sigset_t *set, sigset_t *oldset);
  39
  40 /* Allocate and activate an alternate signal stack.  This stack will
  41    have SIZE + MINSIGSTKSZ bytes of space, rounded up to a whole
  42    number of pages.  There will be large (at least 1 MiB) inaccessible
  43    guard bands on either side of it.  The return value is a cookie
  44    that can be passed to xfree_sigstack to deactivate and deallocate
  45    the stack again.  It is not necessary to call sigaltstack after
  46    calling this function.  Terminates the process on error.  */
  47 void *xalloc_sigstack (size_t size);
  48
  49 /* Deactivate and deallocate a signal stack created by xalloc_sigstack.  */
  50 void xfree_sigstack (void *stack);
  51
  52 /* Extract the actual address and size of the alternate signal stack from
  53    the cookie returned by xalloc_sigstack.  */
  54 void xget_sigstack_location (const void *stack, unsigned char **addrp,
  55                              size_t *sizep);
  56
  57 __END_DECLS
  58
  59 #endif /* SUPPORT_SIGNAL_H */