Introduce walk_func

src/ucore_threadqueue.c

@@ -149,8 +149,33 @@ int uc_thread_queue_get(struct uc_threadqueue *queue, const struct timespec *tim
     return 0;
 }
 
+static void uc_thread_queue_walk_unlocled(struct uc_threadqueue *queue, uc_thread_queue_walk_func walk_func)
+{
+    struct uc_threadmsg *p;
+    struct uc_threadmsg *next;
+    for(p = queue->first; p; p = next) {
+        next = p->next;
+        walk_func(p);
+    }
+}
+
+int uc_thread_queue_walk(struct uc_threadqueue *queue, uc_thread_queue_walk_func walk_func)
+{
+    if (queue == NULL || !walk_func) {
+        return EINVAL;
+    }
+
+    pthread_mutex_lock(&queue->mutex);
+
+    uc_thread_queue_walk_unlocled(queue, walk_func);
+
+    pthread_mutex_unlock(&queue->mutex);
+
+    return 0;
+}
+
 //maybe caller should supply a callback for cleaning the elements ?
-int uc_thread_queue_cleanup(struct uc_threadqueue *queue, int freedata)
+int uc_thread_queue_cleanup(struct uc_threadqueue *queue, uc_thread_queue_walk_func free_func)
 {
     int rc;
 
@@ -172,13 +197,8 @@ int uc_thread_queue_cleanup(struct uc_threadqueue *queue, int freedata)
         return EBUSY;
     }
 
-    if(freedata) {
+    if(free_func) {
-        struct uc_threadmsg *p;
+        uc_thread_queue_walk_unlocled(queue, free_func);
-        struct uc_threadmsg *next;
-        for(p = queue->first; p; p = next) {
-            next = p->next;
-            free(p);
-        }
     }
 
     pthread_mutex_unlock(&queue->mutex);
@@ -190,6 +210,7 @@ int uc_thread_queue_cleanup(struct uc_threadqueue *queue, int freedata)
 
 }
 
+
 long thread_queue_length(struct uc_threadqueue *queue)
 {
     long length;

src/ucore_threadqueue.h

@@ -70,6 +70,8 @@ struct uc_threadmsg{
     struct uc_threadmsg *next;
 };
 
+typedef int (*uc_thread_queue_walk_func) (struct uc_threadmsg *msg);
+
 
 /**
  * A ThreadQueue
@@ -242,22 +244,36 @@ long uc_thread_queue_length( struct uc_threadqueue *queue );
 
 /**
  * @ingroup ThreadQueue
- * Destroy a queue.
- * 
  * Destroy the queue.
  *
- * If freedata is != 0 free(3) will be called on all pending messages in the queue
+ * If free_func is != NULL, free_func will be called for every item, allowing you to free
+ * the item.
  * You cannot call this if there are someone currently adding or getting messages
  * from the queue.
  * After a queue have been cleaned, it cannot be used again untill #thread_queue_init
  * has been called on the queue.
  * 
  * @param queue Pointer to the queue that should be cleaned
- * @param freedata set to nonzero if free(3) should be called on remaining
+ * @param free_func pointer to function that will be called for each item. 
- * messages
+ *  The function must not in anyway interact with the queue.
  * @return 0 on success EINVAL if queue is NULL EBUSY if someone is holding any locks on the queue
  */
-int uc_thread_queue_destroy(struct uc_threadqueue *queue, int freedata);
+int uc_thread_queue_destroy(struct uc_threadqueue *queue, uc_thread_queue_walk_func free_func);
+
+/**
+ * @ingroup ThreadQueue
+ * Walk the elements of the queue, intended for debugging
+ * 
+ * The supplied function will be called for each item in the queue, internal queue
+ * locks are held while the function is called, so the supplied function must not 
+ * interact with the queue, else deadlock occors.
+ * 
+ * @param queue Pointer to the queue to walk
+ * @param free_func pointer to function that will be called for each item. 
+ *  The function must not in anyway interact with the queue.
+ * @return 0 on success 
+ */
+int uc_thread_queue_walk(struct uc_threadqueue *queue, uc_thread_queue_walk_func walk_func);
 
 #ifdef __cplusplus
 }