int shlock_tryopen(shkey_t *key, int flags, shlock_t **lock_p)
{
shmap_t *lock_map = get_shlock_map();
shlock_t *lk;
pid_t tid;
#ifdef USE_LIBPTHREAD
pthread_mutexattr_t attr;
int err;
#endif
tid = gettid();
lk = shmap_get_ptr(lock_map, key);
if (!lk) {
lk = (shlock_t *)calloc(1, sizeof(shlock_t));
if (!lk)
return (-1);
shmap_set_ptr(lock_map, key, lk);
#ifdef USE_LIBPTHREAD
memset(&attr, 0, sizeof(attr));
if (!(flags & SHLK_PRIVATE)) {
pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
}
pthread_mutex_init(&lk->mutex, &attr);
#endif
} else if (lk->ref) {
if ((flags & SHLK_PRIVATE)) {
/* mutex is already locked. */
return (1);
}
if (tid != lk->tid)
return (1); /* lock is not accessible from this thread. */
}
if (!lk->ref || lk->tid != tid) {
#ifdef USE_LIBPTHREAD
/* returns an errno */
err = pthread_mutex_trylock(&lk->mutex);
if (err == EBUSY)
return (1);
if (err)
return (-1);
#endif
}
/* assign variables after mutex is locked. */
lk->tid = tid;
lk->ref++;
*lock_p = lk;
return (0);
}
shlock_t *shlock_open(shkey_t *key, int flags)
{
shmap_t *lock_map = get_shlock_map();
shlock_t *lk;
pid_t tid;
#ifdef USE_LIBPTHREAD
pthread_mutexattr_t attr;
int err;
#endif
tid = gettid();
lk = shmap_get_ptr(lock_map, key);
if (!lk) {
lk = (shlock_t *)calloc(1, sizeof(shlock_t));
if (!lk)
return (NULL);
shmap_set_ptr(lock_map, key, lk);
#ifdef USE_LIBPTHREAD
memset(&attr, 0, sizeof(attr));
if (!(flags & SHLK_PRIVATE)) {
pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
}
pthread_mutex_init(&lk->mutex, &attr);
#endif
}
#ifdef USE_LIBPTHREAD
err = pthread_mutex_lock(&lk->mutex);
if (err) {
return (NULL);
}
#else
/* bug: acts like trylock() instead of lock() .. need to introduce waiting psuedo-lock */
if (lk->ref) {
if ((flags & SHLK_PRIVATE)) {
/* mutex is already locked. */
return (NULL);
}
if (tid != lk->tid) {
return (NULL); /* lock is not accessible from this thread. */
}
}
#endif
/* assign variables after mutex is locked. */
lk->tid = tid;
lk->ref++;
return (lk);
}
char *sexe_event_init(int e_type, const char *e_name)
{
static char key_str[256];
sexe_event_t *e;
shkey_t *key;
if (!event_map) {
event_map = shmap_init();
}
e = (sexe_event_t *)calloc(1, sizeof(sexe_event_t));
if (!e)
return (SHERR_NOMEM);
e->event_type = e_type;
strncpy(e->mod_name, e_name, sizeof(e->mod_name) - 1);
key = shkey_bin(e, sizeof(sexe_event_t));
memcpy(&e->reg_key, key, sizeof(shkey_t));
shmap_set_ptr(event_map, key, e);
strncpy(key_str, shkey_hex(key), sizeof(key_str) - 1);
shkey_free(&key);
return (key_str);
}
