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/* make sure we can vfork/exec across setjmp/longjmp's
* and make sure signal block masks don't get corrupted
* in the process.
*/
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <unistd.h>
#include <errno.h>
#include <setjmp.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <string.h>
int verbose = 0;
int execute_child(const char *prog)
{
int status;
pid_t child;
child = vfork();
if (child == 0) {
execlp(prog, prog, NULL);
perror("Could not execute specified prog");
_exit(1);
} else if (child == 1)
return 1;
wait(&status);
return WEXITSTATUS(status);
}
sigset_t orig_mask;
int check_sig_mask(void)
{
int status;
pid_t child;
child = vfork();
if (child == 0) {
int ret;
sigset_t child_mask;
memset(&child_mask, 0x00, sizeof(child_mask));
ret = sigprocmask(SIG_BLOCK, NULL, &child_mask);
if (ret != 0) {
perror("could not get child sig block mask");
_exit(1);
}
ret = memcmp(&orig_mask, &child_mask, sizeof(orig_mask));
if (verbose) {
printf("sigmsk: %08lx%08lx ", child_mask.__val[1], child_mask.__val[0]);
printf("sigmsk: %08lx%08lx ", orig_mask.__val[1], orig_mask.__val[0]);
printf("%i\n", ret);
}
_exit(ret);
} else if (child == 1)
return 1;
wait(&status);
return WEXITSTATUS(status);
}
int main(int argc, char *argv[])
{
const char *prog;
jmp_buf env;
sigjmp_buf sigenv;
int cnt, max, ret;
memset(&orig_mask, 0x00, sizeof(orig_mask));
ret = sigprocmask(SIG_BLOCK, NULL, &orig_mask);
if (ret != 0) {
perror("could not get orig sig block mask");
return 1;
}
prog = (argc > 1 ? argv[1] : "true");
ret = 0;
verbose = 0;
max = 10;
/* test vfork() instead of sigsetjmp/siglongjmp */
cnt = 0;
sigsetjmp(sigenv, 1);
++cnt;
if (verbose)
printf("sigsetjmp loop %i\n", cnt);
ret |= check_sig_mask();
ret |= execute_child(prog);
if (cnt < max)
siglongjmp(sigenv, 0);
/* test vfork() inside of setjmp/longjmp */
cnt = 0;
setjmp(env);
++cnt;
if (verbose)
printf("setjmp loop %i\n", cnt);
ret |= check_sig_mask();
ret |= execute_child(prog);
if (cnt < max)
longjmp(env, 0);
return ret;
}
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