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/* Copyright (c) 2010-2025. The SimGrid Team. All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
#ifdef __APPLE__
#define _XOPEN_SOURCE 700
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ucontext.h>
union alltypes {
long l;
double d;
void *vp;
void (*fp) (void);
char *cp;
};
static char *handler_addr = (char *) 0xDEAD;
static ucontext_t uc_handler;
static ucontext_t uc_main;
void handler(void)
{
char garbage[1024];
auto int dummy;
int i;
for (i = 0; i < 1024; i++)
garbage[i] = 'X';
handler_addr = (char *) &dummy;
swapcontext(&uc_handler, &uc_main);
return;
}
int main(int argc, char *argv[])
{
int sksize = 32768;
char *skbuf = (char *) malloc(sksize * 2 + 2 * sizeof(union alltypes));
if (skbuf == NULL)
exit(1);
int i;
for (i = 0; i < sksize * 2 + 2 * sizeof(union alltypes); i++)
skbuf[i] = 'A';
char *skaddr = skbuf + sizeof(union alltypes);
if (getcontext(&uc_handler) != 0)
exit(1);
uc_handler.uc_link = NULL;
uc_handler.uc_stack.ss_sp = (void *) (skaddr + sksize);
uc_handler.uc_stack.ss_size = sksize;
uc_handler.uc_stack.ss_flags = 0;
makecontext(&uc_handler, handler, 0);
swapcontext(&uc_main, &uc_handler);
if (handler_addr == (char *) 0xDEAD)
exit(1);
if (handler_addr < skaddr + sksize) {
/* stack was placed into lower area */
if (*(skaddr + sksize) != 'A')
printf("(skaddr)+(sksize)-%zu;(sksize)-%zu", sizeof(union alltypes), sizeof(union alltypes));
else
printf("(skaddr)+(sksize);(sksize)");
} else {
/* stack was placed into higher area */
if (*(skaddr + sksize * 2) != 'A')
printf("(skaddr);(sksize)-%zu", sizeof(union alltypes));
else
printf("(skaddr);(sksize)");
}
return 0;
}
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