setjmp/setjmp.h

   1 /* Copyright (C) 1991-1999, 2001 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 /*
  20  *      ISO C99 Standard: 7.13 Nonlocal jumps   <setjmp.h>
  21  */
  22
  23 #ifndef _SETJMP_H
  24 #define _SETJMP_H       1
  25
  26 #include <features.h>
  27
  28 __BEGIN_DECLS
  29
  30 #include <bits/setjmp.h>                /* Get `__jmp_buf'.  */
  31 #include <bits/sigset.h>                /* Get `__sigset_t'.  */
  32
  33 /* Calling environment, plus possibly a saved signal mask.  */
  34 typedef struct __jmp_buf_tag    /* C++ doesn't like tagless structs.  */
  35   {
  36     /* NOTE: The machine-dependent definitions of `__sigsetjmp'
  37        assume that a `jmp_buf' begins with a `__jmp_buf' and that
  38        `__mask_was_saved' follows it.  Do not move these members
  39        or add others before it.  */
  40     __jmp_buf __jmpbuf;         /* Calling environment.  */
  41     int __mask_was_saved;       /* Saved the signal mask?  */
  42     __sigset_t __saved_mask;    /* Saved signal mask.  */
  43   } jmp_buf[1];
  44
  45
  46 /* Store the calling environment in ENV, also saving the signal mask.
  47    Return 0.  */
  48 extern int setjmp (jmp_buf __env) __THROW;
  49
  50 /* Store the calling environment in ENV, not saving the signal mask.
  51    Return 0.  */
  52 extern int _setjmp (jmp_buf __env) __THROW;
  53
  54 /* Store the calling environment in ENV, also saving the
  55    signal mask if SAVEMASK is nonzero.  Return 0.
  56    This is the internal name for `sigsetjmp'.  */
  57 extern int __sigsetjmp (jmp_buf __env, int __savemask) __THROW;
  58
  59 #ifndef __FAVOR_BSD
  60 /* Do not save the signal mask.  This is equivalent to the `_setjmp'
  61    BSD function.  */
  62 # define setjmp(env)    _setjmp (env)
  63 #else
  64 /* We are in 4.3 BSD-compatibility mode in which `setjmp'
  65    saves the signal mask like `sigsetjmp (ENV, 1)'.  We have to
  66    define a macro since ISO C says `setjmp' is one.  */
  67 # define setjmp(env)    setjmp (env)
  68 #endif /* Favor BSD.  */
  69
  70
  71 /* Jump to the environment saved in ENV, making the
  72    `setjmp' call there return VAL, or 1 if VAL is 0.  */
  73 extern void longjmp (jmp_buf __env, int __val)
  74      __THROW __attribute__ ((__noreturn__));
  75 #if defined __USE_BSD || defined __USE_XOPEN
  76 /* Same.  Usually `_longjmp' is used with `_setjmp', which does not save
  77    the signal mask.  But it is how ENV was saved that determines whether
  78    `longjmp' restores the mask; `_longjmp' is just an alias.  */
  79 extern void _longjmp (jmp_buf __env, int __val)
  80      __THROW __attribute__ ((__noreturn__));
  81 #endif
  82
  83
  84 #ifdef  __USE_POSIX
  85 /* Use the same type for `jmp_buf' and `sigjmp_buf'.
  86    The `__mask_was_saved' flag determines whether
  87    or not `longjmp' will restore the signal mask.  */
  88 typedef jmp_buf sigjmp_buf;
  89
  90 /* Store the calling environment in ENV, also saving the
  91    signal mask if SAVEMASK is nonzero.  Return 0.  */
  92 # define sigsetjmp(env, savemask)       __sigsetjmp (env, savemask)
  93
  94 /* Jump to the environment saved in ENV, making the
  95    sigsetjmp call there return VAL, or 1 if VAL is 0.
  96    Restore the signal mask if that sigsetjmp call saved it.
  97    This is just an alias `longjmp'.  */
  98 extern void siglongjmp (sigjmp_buf __env, int __val)
  99      __THROW __attribute__ ((__noreturn__));
 100 #endif /* Use POSIX.  */
 101
 102 __END_DECLS
 103
 104 #endif /* setjmp.h  */