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/* Test of setjmp()/longjmp() functions: frame pointer restoring.
$Id: setjmp-4.c,v 1.1.2.2 2008/03/24 11:29:55 dmix Exp $ */
#include <setjmp.h>
#include <stdlib.h>
#include <string.h>
jmp_buf env;
/* foo_jmp() use stack. longjmp must restore frame pointer from env. */
void foo_jmp (const char *p)
{
char s[16];
strcpy (s, p);
s[0] += 1;
longjmp (env, strtol (s, 0, 0));
}
/* foo() use stack. If frame pointer would be scratch, return value
(or all program) would be another. */
int foo (char *p)
{
volatile char s[16];
strcpy ((char *)s, p);
switch (setjmp (env)) {
case 0: break;
case 2: return strtol ((const char *)s, 0, 0);
default: exit (__LINE__);
}
foo_jmp ("1");
exit (__LINE__);
}
int main ()
{
if (foo ("1234") != 1234)
exit (__LINE__);
if (foo ("4321") != 4321)
exit (__LINE__);
return 0;
}
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