Added thread safe work queue

src/main.c

@@ -15,6 +15,7 @@
 #include <sys/mman.h>
 #include <ctype.h>
 #include <signal.h>
+#include <bits/stdio2.h>
 
 #include "http_parser.h"
 
@@ -27,6 +28,7 @@
 #include "config.h"
 #include "http-server.h"
 #include "mime.h"
+#include "queue.h"
 
 int serverfd = 0;
 volatile static bool stop = false;

src/queue.c

@@ -0,0 +1,78 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <pthread.h>
+
+#include "queue.h"
+#include "util.h"
+#include "ut/utlist.h"
+
+queue_item* queue_item_new() {
+    queue_item *item = calloc(1, sizeof(queue_item));
+    return item;
+}
+void queue_item_delete(queue_item *item) {
+    free(item);
+}
+
+queue* queue_new() {
+    queue *q = calloc(1, sizeof(queue));
+    q->count = 0;
+    q->list = NULL;
+    q->mutex = calloc(1, sizeof(pthread_mutex_t));
+    if (pthread_mutex_init(q->mutex, NULL) != 0) {
+        fatal("Failed to init queue mutex");
+    }
+    q->cond = calloc(1, sizeof(pthread_cond_t));
+    if (pthread_cond_init(q->cond, NULL) != 0) {
+        fatal("Failed to init queue cond");
+    }
+    
+    return q;
+}
+void queue_delete(queue *q) {
+    queue_item *elem, *tmp;
+    DL_FOREACH_SAFE(q->list, elem, tmp) {
+        queue_item_delete(elem);
+        DL_DELETE(q->list, elem);
+    }
+    pthread_mutex_destroy(q->mutex);
+    free(q->mutex);
+    pthread_cond_destroy(q->cond);
+    free(q->cond);
+    free(q);
+}
+int queue_add(queue *q, queue_item *item) {
+    QUEUE_LOCK(q);
+    DL_APPEND(q->list, item);
+    q->count++;
+    pthread_cond_signal(q->cond);
+    QUEUE_UNLOCK(q);
+    return 0;
+}
+int queue_remove(queue *q, queue_item *item) {
+    QUEUE_LOCK(q);
+    queue_item *elem, *tmp;
+    DL_FOREACH_SAFE(q->list, elem, tmp) {
+        if (elem == item) {
+            DL_DELETE(q->list, elem);
+            queue_item_delete(elem);
+            break;
+        }
+    }
+    q->count--;
+    QUEUE_UNLOCK(q);
+}
+queue_item* queue_fetchone(queue *q, bool blocking) {
+    queue_item *item = NULL;
+    QUEUE_LOCK(q);
+    if (q->count == 0 && blocking == true) {
+        pthread_cond_wait(q->cond, q->mutex);
+    }
+    if (q->count > 0) {
+        item = q->list;
+        DL_DELETE(q->list, q->list);
+        q->count--;
+    }
+    QUEUE_UNLOCK(q);
+    return item;
+}

src/queue.h

@@ -0,0 +1,60 @@
+/* 
+ * File:   queue.h
+ * Author: sam
+ *
+ * Created on 04 August 2014, 14:27
+ */
+
+#ifndef QUEUE_H
+#define	QUEUE_H
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+#include <pthread.h>
+#include <stdint.h>
+#include <stdbool.h>
+    
+    typedef struct queue_item {
+        struct queue_item *prev;
+        struct queue_item *next;
+        char tag[16];
+        void *data;
+    } queue_item;
+    
+    queue_item* queue_item_new();
+    void queue_item_delete(queue_item *item);
+    
+    typedef struct queue {
+        queue_item *list;
+        uint64_t count;
+        pthread_mutex_t *mutex;
+        pthread_cond_t *cond;
+   } queue;
+   
+#define QUEUE_LOCK(q)                           \
+    do {                                        \
+        if (pthread_mutex_lock(q->mutex)!=0) {  \
+            fatal("Could not lock queue");      \
+        }                                       \
+    } while(0)
+#define QUEUE_UNLOCK(q)                         \
+    do {                                        \
+        if (pthread_mutex_unlock(q->mutex)!=0) {\
+            fatal("Could not unlock queue");    \
+        }                                       \
+    } while(0)
+   
+   queue* queue_new();
+   void queue_delete(queue *q);
+   int queue_add(queue *q, queue_item *item);
+   int queue_remove(queue *q, queue_item *item);
+   queue_item* queue_fetchone(queue *q, bool blocking);
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif	/* QUEUE_H */
+