1 files changed, 127 insertions, 0 deletions
diff --git a/tacplus-daemon/queue.c b/tacplus-daemon/queue.c
new file mode 100644
index 0000000..fae583f
--- /dev/null
+++ b/tacplus-daemon/queue.c
@@ -0,0 +1,127 @@
+/*
+	TACACS+ D-Bus Daemon code
+
+	Copyright (c) 2018 AT&T Intellectual Property.
+	Copyright (c) 2015-2016 Brocade Communications Systems, Inc.
+
+	SPDX-License-Identifier: GPL-2.0-only
+*/
+
+#include "queue.h"
+
+Queue * create_queue(void (*free_element)(void *))
+{
+	Queue *q;
+	q = malloc(sizeof(*q));
+
+	if (q == NULL) {
+		syslog(LOG_ERR, "Failed to allocate queue");
+	}
+	else {
+		q->front = NULL;
+		q->rear = NULL;
+		q->free_element = free_element;
+		pthread_mutex_init(&(q->lock), NULL);
+		pthread_cond_init(&(q->empty), NULL);
+	}
+	return q;
+}
+
+void enqueue(Queue *q, void *e)
+{
+	Node *n;
+
+	if (q == NULL || e == NULL)
+		return;
+
+	pthread_mutex_lock(&(q->lock));
+
+	n = malloc(sizeof(*n));
+	n->element = e;
+	n->next = NULL;
+
+	if (is_queue_empty(q)) {
+		q->front = n;
+		q->rear = n;
+	}
+	else {
+		q->rear->next = n;
+		q->rear = n;
+	}
+	pthread_cond_broadcast(&(q->empty));
+	pthread_mutex_unlock(&(q->lock));
+}
+
+void re_enqueue(Queue *q, void *e)
+{
+	Node *n;
+
+	if (q == NULL || e == NULL)
+		return;
+
+	pthread_mutex_lock(&(q->lock));
+
+	n = malloc(sizeof(*n));
+	n->element = e;
+	n->next = q->front;
+
+	if (is_queue_empty(q)) {
+		q->front = n;
+		q->rear = n;
+	}
+	else {
+		q->front = n;
+	}
+	pthread_cond_broadcast(&(q->empty));
+	pthread_mutex_unlock(&(q->lock));
+}
+
+void * dequeue(Queue *q)
+{
+	Node *n, *nextNode;
+	void *data = NULL;
+
+	pthread_mutex_lock(&(q->lock));
+
+	if (!is_queue_empty(q)) {
+		n = q->front;
+		nextNode = q->front->next;
+		if (q->front == q->rear) {
+			q->rear = nextNode;
+		}
+		q->front = nextNode;
+		data = n->element;
+		free(n);
+	}
+	pthread_cond_broadcast(&(q->empty));
+	pthread_mutex_unlock(&(q->lock));
+	return data;
+}
+
+int is_queue_empty(Queue *q)
+{
+	return (q->front == NULL);
+}
+
+void destroy_queue(Queue **q)
+{
+	Node *n = NULL;
+	Node *next_n;
+
+	if (!q || !*q)
+		return;
+
+	for (n = (*q)->front; n != NULL ; n = next_n) {
+		next_n = n->next;
+		if((*q)->free_element)
+			(*q)->free_element(n->element);
+		free(n);
+	}
+
+	pthread_mutex_destroy(&((*q)->lock));
+	pthread_cond_destroy(&((*q)->empty));
+
+	free(*q);
+	*q = NULL;
+}
+