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#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include "tests/sys_mman.h"
void sig_handler(int sig){
int var;
fprintf(stderr, "caught signal, local var is on %p\n", &var);
}
int main(int argv, char** argc) {
int res, i;
stack_t sigstk;
struct sigaction act;
static const int size = SIGSTKSZ*2;
// We give EXEC permissions because this won't work on ppc32 unless you
// ask for an alt stack with EXEC permissions,
// since signal returning requires execution of code on the stack.
char *stk = (char *)mmap(0, size, PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
sigstk.ss_sp = stk;
sigstk.ss_size = size;
sigstk.ss_flags = 0;
fprintf(stderr, "calling sigaltstack, stack base is %p\n", sigstk.ss_sp);
if (sigaltstack(&sigstk,0)<0) perror("sigaltstack");
fprintf(stderr,"setting sigaction\n");
act.sa_flags=SA_ONSTACK;
act.sa_handler=&sig_handler;
sigemptyset(&act.sa_mask);
res = sigaction(SIGUSR1,&act,0);
fprintf(stderr, "res = %d\n", res);
fprintf(stderr, "raising the signal\n");
raise(SIGUSR1);
/* Loop long enough so valgrind has a forced context switch and
actually delivers the signal before the thread exits. */
for (i = 0; i < 1000000; i++) ;
fprintf(stderr, "done\n");
return 0;
}
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