* allocLock is used by Tcl's version of malloc for synchronization. For
 * obvious reasons, cannot use any dyamically allocated storage.
 */

static pthread_mutex_t allocLock = PTHREAD_MUTEX_INITIALIZER;
static pthread_mutex_t *allocLockPtr = &allocLock;

/*
 * These are for the critical sections inside this file.
 */

#define MASTER_LOCK	pthread_mutex_lock(&masterLock)
#define MASTER_UNLOCK	pthread_mutex_unlock(&masterLock)

#endif /* TCL_THREADS */

/*
 *----------------------------------------------------------------------
 *
 * TclpThreadCreate --
 *

void
Tcl_MutexLock(
    Tcl_Mutex *mutexPtr)	/* Really (pthread_mutex_t **) */
{
    pthread_mutex_t *pmutexPtr;

    if (*mutexPtr == NULL) {
	pthread_mutex_lock(&masterLock);
	MASTER_LOCK;
	if (*mutexPtr == NULL) {
	    /*
	     * Double inside master lock check to avoid a race condition.
	     */

	    pmutexPtr = ckalloc(sizeof(pthread_mutex_t));
	    pthread_mutex_init(pmutexPtr, NULL);
	    *mutexPtr = (Tcl_Mutex)pmutexPtr;
	    TclRememberMutex(mutexPtr);
	}
	pthread_mutex_unlock(&masterLock);
	MASTER_UNLOCK;
    }
    pmutexPtr = *((pthread_mutex_t **)mutexPtr);
    pthread_mutex_lock(pmutexPtr);
}

/*
 *----------------------------------------------------------------------

    const Tcl_Time *timePtr) /* Timeout on waiting period */
{
    pthread_cond_t *pcondPtr;
    pthread_mutex_t *pmutexPtr;
    struct timespec ptime;

    if (*condPtr == NULL) {
	pthread_mutex_lock(&masterLock);
	MASTER_LOCK;

	/*
	 * Double check inside mutex to avoid race, then initialize condition
	 * variable if necessary.
	 */

	if (*condPtr == NULL) {
	    pcondPtr = ckalloc(sizeof(pthread_cond_t));
	    pthread_cond_init(pcondPtr, NULL);
	    *condPtr = (Tcl_Condition) pcondPtr;
	    TclRememberCondition(condPtr);
	}
	pthread_mutex_unlock(&masterLock);
	MASTER_UNLOCK;
    }
    pmutexPtr = *((pthread_mutex_t **)mutexPtr);
    pcondPtr = *((pthread_cond_t **)condPtr);
    if (timePtr == NULL) {
	pthread_cond_wait(pcondPtr, pmutexPtr);
    } else {
	Tcl_Time now;