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, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <stdio.h>
  19 #include <setjmp.h>
  20 #include <stdlib.h>
  21
  22 static jmp_buf env;
  23 static int last_value = -1, lose = 0;
  24
  25 static void
  26 jump (int val)
  27 {
  28   longjmp (env, val);
  29 }
  30
  31 int
  32 main (void)
  33 {
  34   int value;
  35
  36   value = setjmp (env);
  37   if (value != last_value + 1)
  38     {
  39       fputs("Shouldn't have ", stdout);
  40       lose = 1;
  41     }
  42   last_value = value;
  43   switch (value)
  44     {
  45     case 0:
  46       puts("Saved environment.");
  47       jump (0);
  48     default:
  49       printf ("Jumped to %d.\n", value);
  50       if (value < 10)
  51         jump (value + 1);
  52     }
  53
  54   if (!lose && value == 10)
  55     {
  56       /* Do a second test, this time without `setjmp' being a macro.
  57          This is not required by ISO C but we have this for compatibility.  */
  58 #undef setjmp
  59       extern int setjmp (jmp_buf);
  60
  61       last_value = -1;
  62       lose = 0;
  63
  64       value = setjmp (env);
  65       if (value != last_value + 1)
  66         {
  67           fputs("Shouldn't have ", stdout);
  68           lose = 1;
  69         }
  70       last_value = value;
  71       switch (value)
  72         {
  73         case 0:
  74           puts("Saved environment.");
  75           jump (0);
  76         default:
  77           printf ("Jumped to %d.\n", value);
  78           if (value < 10)
  79             jump (value + 1);
  80         }
  81     }
  82
  83   if (!lose && value == 10)
  84     {
  85       /* And again for the `_setjmp' function.  */
  86 #ifndef _setjmp
  87       extern int _setjmp (jmp_buf);
  88 #endif
  89       last_value = -1;
  90       lose = 0;
  91
  92       value = _setjmp (env);
  93       if (value != last_value + 1)
  94         {
  95           fputs("Shouldn't have ", stdout);
  96           lose = 1;
  97         }
  98       last_value = value;
  99       switch (value)
 100         {
 101         case 0:
 102           puts("Saved environment.");
 103           jump (0);
 104         default:
 105           printf ("Jumped to %d.\n", value);
 106           if (value < 10)
 107             jump (value + 1);
 108         }
 109     }
 110
 111   if (lose || value != 10)
 112     puts ("Test FAILED!");
 113   else
 114     puts ("Test succeeded!");
 115
 116   return lose ? EXIT_FAILURE : EXIT_SUCCESS;
 117 }