Add a public API for the thread-safe message queue.

[meshlink] / src / meshlink_queue.h

diff --git a/src/meshlink_queue.h b/src/meshlink_queue.h
new file mode 100644 (file)
index 0000000..a1f2524
--- /dev/null
+++ b/src/meshlink_queue.h
@@ -0,0 +1,71 @@
+/*
+    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