setjmp/tst-setjmp.c

   1 /* Copyright (C) 1991, 1992, 1997, 1998, 2000 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 #include <stdio.h>
  20 #include <setjmp.h>
  21 #include <stdlib.h>
  22
  23 static jmp_buf env;
  24 static int last_value = -1, lose = 0;
  25
  26 static void
  27 jump (int val)
  28 {
  29   longjmp (env, val);
  30 }
  31
  32 int
  33 main (void)
  34 {
  35   int value;
  36
  37   value = setjmp (env);
  38   if (value != last_value + 1)
  39     {
  40       fputs("Shouldn't have ", stdout);
  41       lose = 1;
  42     }
  43   last_value = value;
  44   switch (value)
  45     {
  46     case 0:
  47       puts("Saved environment.");
  48       jump (0);
  49     default:
  50       printf ("Jumped to %d.\n", value);
  51       if (value < 10)
  52         jump (value + 1);
  53     }
  54
  55   if (!lose && value == 10)
  56     {
  57       /* Do a second test, this time without `setjmp' being a macro.
  58          This is not required by ISO C but we have this for compatibility.  */
  59 #undef setjmp
  60       extern int setjmp (jmp_buf);
  61
  62       last_value = -1;
  63       lose = 0;
  64
  65       value = setjmp (env);
  66       if (value != last_value + 1)
  67         {
  68           fputs("Shouldn't have ", stdout);
  69           lose = 1;
  70         }
  71       last_value = value;
  72       switch (value)
  73         {
  74         case 0:
  75           puts("Saved environment.");
  76           jump (0);
  77         default:
  78           printf ("Jumped to %d.\n", value);
  79           if (value < 10)
  80             jump (value + 1);
  81         }
  82     }
  83
  84   if (!lose && value == 10)
  85     {
  86       /* And again for the `_setjmp' function.  */
  87 #ifndef _setjmp
  88       extern int _setjmp (jmp_buf);
  89 #endif
  90       last_value = -1;
  91       lose = 0;
  92
  93       value = _setjmp (env);
  94       if (value != last_value + 1)
  95         {
  96           fputs("Shouldn't have ", stdout);
  97           lose = 1;
  98         }
  99       last_value = value;
 100       switch (value)
 101         {
 102         case 0:
 103           puts("Saved environment.");
 104           jump (0);
 105         default:
 106           printf ("Jumped to %d.\n", value);
 107           if (value < 10)
 108             jump (value + 1);
 109         }
 110     }
 111
 112   if (lose || value != 10)
 113     puts ("Test FAILED!");
 114   else
 115     puts ("Test succeeded!");
 116
 117   return lose ? EXIT_FAILURE : EXIT_SUCCESS;
 118 }