Semaphore Implementation

Semaphore_Implementation/Semaphore_Implementation.c

@@ -0,0 +1,70 @@
+#include <stdlib.h>
+#include <assert.h>
+#include <stdbool.h>
+#include "Semaphore_Implementation.h"
+
+sema_t*
+sema_get_new_semaphore() {
+
+	sema_t* sema = calloc(1, sizeof(sema_t));
+	return sema;
+
+}
+
+void
+sema_init(sema_t* sema, int permit_counter) {
+
+	sema->permit_counter = permit_counter;
+	pthread_cond_init(&sema->cv, NULL);
+	pthread_mutex_init(&sema->mutex, NULL);
+
+}
+
+/*
+	Without using Pending Signals
+*/
+
+void
+sema_wait(sema_t* sema) {
+
+	pthread_mutex_lock(&sema->mutex);
+	sema->permit_counter--;
+	if (sema->permit_counter < 0) {
+		pthread_cond_wait(&sema->cv, &sema->mutex);
+	}
+	pthread_mutex_unlock(&sema->mutex);
+
+}
+
+void
+sema_post(sema_t* sema) {
+
+	bool any_thread_waiting;
+	pthread_mutex_lock(&sema->mutex);
+
+	any_thread_waiting = sema->permit_counter < 0 ? true : false;
+	sema->permit_counter++;
+
+	if (any_thread_waiting) {
+		pthread_cond_signal(&sema->cv);
+	}
+	pthread_mutex_unlock(&sema->mutex);
+
+}
+
+void
+sema_destroy(sema_t* sema) {
+
+	sema->permit_counter = 0;
+	pthread_mutex_unlock(&sema->mutex);
+	pthread_cond_destroy(&sema->cv);
+	pthread_mutex_destroy(&sema->mutex);
+
+}
+
+int
+sema_getvalue(sema_t* sema) {
+
+	return sema->permit_counter;
+
+}