root/maint/gnulib/lib/c-stack.h

/* */

INCLUDED FROM

   1 /* Stack overflow handling.
   2 
   3    Copyright (C) 2002, 2004, 2008-2021 Free Software Foundation, Inc.
   4 
   5    This program is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9 
  10    This program 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
  13    GNU General Public License for more details.
  14 
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17 
  18 
  19 /* Set up ACTION so that it is invoked on C stack overflow and on other,
  20    stack-unrelated, segmentation violation.
  21    Return -1 (setting errno) if this cannot be done.
  22 
  23    When a stack overflow or segmentation violation occurs:
  24    1) ACTION is called.  It is passed an argument equal to
  25         - 0, for a stack overflow,
  26         - SIGSEGV, for a segmentation violation that does not appear related
  27           to stack overflow.
  28       On many platforms the two cases are hard to distinguish; when in doubt,
  29       zero is passed.
  30    2) If ACTION returns, a message is written to standard error, and the
  31       program is terminated: in the case of stack overflow, with exit code
  32       exit_failure (see "exitfail.h"), otherwise through a signal SIGSEGV.
  33 
  34    A null ACTION acts like an action that does nothing.
  35 
  36    Restrictions:
  37    - ACTION must be async-signal-safe.
  38    - ACTION together with its callees must not require more than 64 KiB of
  39      stack space.
  40    - ACTION must not create and then invoke nested functions
  41      <https://gcc.gnu.org/onlinedocs/gcc/Nested-Functions.html>, because
  42      this implementation does not guarantee an executable stack.
  43    - ACTION should not call longjmp, because this implementation does not
  44      guarantee that it is safe to return to the original stack.
  45 
  46    This function may install a handler for the SIGSEGV signal or for the SIGBUS
  47    signal or exercise other system dependent exception handling APIs.  */
  48 
  49 extern int c_stack_action (_GL_ASYNC_SAFE void (* /*action*/) (int));

/* */