static int
_svcond_signal(svcond_t *cond, int broadcast)
{
int signals_to_issue;
if (svsem_wait(cond->unblock_lock) == -1) {
AMSG("");
return -1;
}
if (cond->waiters_to_unblock) {
if (cond->waiters_blocked == 0) {
if (svsem_post(cond->unblock_lock) == -1) {
AMSG("");
return -1;
}
return 0;
}
if (broadcast) {
cond->waiters_to_unblock += signals_to_issue = cond->waiters_blocked;
cond->waiters_blocked = 0;
} else {
signals_to_issue = 1;
cond->waiters_to_unblock++;
cond->waiters_blocked--;
}
} else if (cond->waiters_blocked) {
if (svsem_wait(cond->blocked_lock) == -1) {
AMSG("");
return -1;
}
if (broadcast) {
signals_to_issue = cond->waiters_to_unblock = cond->waiters_blocked;
cond->waiters_blocked = 0;
} else {
signals_to_issue = cond->waiters_to_unblock = 1;
cond->waiters_blocked--;
}
} else {
if (svsem_post(cond->unblock_lock) == -1) {
AMSG("");
return -1;
}
return 0;
}
if (svsem_post(cond->unblock_lock) == -1 ||
svsem_post_multiple(cond->block_queue, signals_to_issue) == -1) {
AMSG("");
return -1;
}
return 0;
}
int
svcond_wait(svcond_t *cond, svsem_t *sem)
{
int signals_left = 0;
if (svsem_wait(cond->blocked_lock) == -1) {
AMSG("");
return -1;
}
cond->waiters_blocked++;
svsem_post(cond->blocked_lock);
svsem_post(sem);
if (svsem_wait(cond->block_queue) == -1) {
int err = errno;
AMSG("");
cond->waiters_blocked--;
while (svsem_wait(sem) == -1 && errno == EINTR) {
;
}
errno = err;
return -1;
}
if (svsem_wait(cond->unblock_lock) == -1) {
int err = errno;
AMSG("");
while (svsem_wait(sem) == -1 && errno == EINTR) {
;
}
errno = err;
return -1;
}
if ((signals_left = cond->waiters_to_unblock)) {
cond->waiters_to_unblock--;
}
svsem_post(cond->unblock_lock);
if (signals_left == 1) {
svsem_post(cond->blocked_lock);
}
while (svsem_wait(sem) == -1) {
if (errno != EINTR) {
AMSG("");
return -1;
}
}
return 0;
}
int
run(void)
{
int fd, *ptr, i;
svsem_t sem;
if ((fd = open("/tmp/SvsemCounter.shm", O_RDWR | O_CREAT, 0600)) == -1 ||
ftruncate(fd, sizeof *ptr) == -1 ||
(ptr = (int *)mmap(NULL, sizeof *ptr, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0)) == NULL) {
return -1;
}
close(fd);
if (svsem_open(&sem, "/tmp/SvsemCounter.sem", SEM_UNDO) == -1) {
return -1;
}
for (i = 0; i < count; i++) {
svsem_wait(&sem);
(*ptr)++;
svsem_post(&sem);
}
svsem_close(&sem);
munmap((void *)ptr, sizeof *ptr);
return 0;
}
int
svcond_destroy(svcond_t *cond)
{
int ret = 0;
if (svsem_wait(cond->blocked_lock) == -1) {
AMSG("");
return -1;
}
if (svsem_trywait(cond->unblock_lock) != 0) {
AMSG("");
svsem_post(cond->blocked_lock);
return -1;
}
if (cond) {
if (cond->blocked_lock) {
ret += pool_release(cond->sempool, cond->blocked_lock);
if (cond->block_queue) {
ret += pool_release(cond->sempool, cond->block_queue);
if (cond->unblock_lock) {
ret += pool_release(cond->sempool, cond->unblock_lock);
cond->unblock_lock = NULL;
}
cond->block_queue = NULL;
}
cond->blocked_lock = NULL;
}
}
return ret ? -1 : 0;
}
