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/* $FreeBSD$ */
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/mman.h>
#include <semaphore.h>
#include <stdio.h>
#include <stdlib.h>
#include <err.h>
#include <fcntl.h>
#include <unistd.h>
#define SEM_NAME "/semtst"
int test_unnamed(void);
int test_named(void);
int
test_unnamed(void)
{
sem_t *s;
pid_t pid;
int status;
printf("testing unnamed process-shared semaphore\n");
s = (sem_t *)mmap(NULL, sizeof(sem_t), PROT_READ|PROT_WRITE, MAP_ANON|MAP_SHARED,
-1, 0);
if (s == MAP_FAILED)
err(1, "mmap failed");
if (sem_init(s, 1, 0))
err(2, "sem_init failed");
if ((pid = fork()) == 0) {
printf("child: sem_wait()\n");
if (sem_wait(s))
err(3, "sem_wait failed");
printf("child: sem_wait() returned\n");
exit(0);
} else {
sleep(1);
printf("parent: sem_post()\n");
if (sem_post(s))
err(4, "sem_post failed");
waitpid(pid, &status, 0);
if (WIFEXITED(status) && WEXITSTATUS(status) == 0)
printf("OK.\n");
else
printf("Failure.");
}
return (0);
}
int
test_named(void)
{
sem_t *s, *s2;
pid_t pid;
int status;
printf("testing named process-shared semaphore\n");
sem_unlink(SEM_NAME);
s = sem_open(SEM_NAME, O_CREAT, 0777, 0);
if (s == SEM_FAILED)
err(1, "sem_open failed");
s2 = sem_open(SEM_NAME, O_CREAT, 0777, 0);
if (s2 == SEM_FAILED)
err(2, "second sem_open call failed");
if (s != s2)
errx(3,
"two sem_open calls for same semaphore do not return same address");
if (sem_close(s2))
err(4, "sem_close failed");
if ((pid = fork()) == 0) {
printf("child: sem_wait()\n");
if (sem_wait(s))
err(5, "sem_wait failed");
printf("child: sem_wait() returned\n");
exit(0);
} else {
sleep(1);
printf("parent: sem_post()\n");
if (sem_post(s))
err(6, "sem_post failed");
waitpid(pid, &status, 0);
if (WIFEXITED(status) && WEXITSTATUS(status) == 0)
printf("OK.\n");
else
printf("Failure.");
}
if (sem_close(s))
err(7, "sem_close failed");
return (0);
}
int
main(void)
{
test_unnamed();
test_named();
return (0);
}
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