+/*
+ queue.h -- Thread-safe queue
+ Copyright (C) 2014 Guus Sliepen <guus@meshlink.io>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#ifndef MESHLINK_QUEUE_H
+#define MESHLINK_QUEUE_H
+
+#include <pthread.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <unistd.h>
+
+typedef struct meshlink_queue {
+ struct meshlink_queue_item *head;
+ struct meshlink_queue_item *tail;
+ pthread_mutex_t mutex;
+} meshlink_queue_t;
+
+typedef struct meshlink_queue_item {
+ void *data;
+ struct meshlink_queue_item *next;
+} meshlink_queue_item_t;
+
+static inline bool meshlink_queue_push(meshlink_queue_t *queue, void *data) {
+ meshlink_queue_item_t *item = malloc(sizeof *item);
+ fprintf(stderr, "Pushing %p %p %p\n", queue, item, data);
+ if(!item)
+ return false;
+ item->data = data;
+ item->next = NULL;
+ pthread_mutex_lock(&queue->mutex);
+ if(!queue->tail)
+ queue->head = queue->tail = item;
+ else
+ queue->tail = queue->tail->next = item;
+ pthread_mutex_unlock(&queue->mutex);
+ return true;
+}
+
+static inline void *meshlink_queue_pop(meshlink_queue_t *queue) {
+ meshlink_queue_item_t *item;
+ void *data;
+ pthread_mutex_lock(&queue->mutex);
+ if((item = queue->head)) {
+ queue->head = item->next;
+ if(!queue->head)
+ queue->tail = NULL;
+ }
+ pthread_mutex_unlock(&queue->mutex);
+ data = item ? item->data : NULL;
+ fprintf(stderr, "Popping %p %p %p\n", queue, item, data);
+ free(item);
+ return data;
+}
+
+#endif