reindentated; add some comments

svn path=/trunk/externals/iem/iemnet/; revision=13869

1 files changed, 81 insertions, 72 deletions

diff --git a/iemnet_data.c b/iemnet_data.c
index 50dd97a..9969e9a 100644
--- a/iemnet_data.c
+++ b/iemnet_data.c
@@ -202,103 +202,112 @@ struct _iemnet_queue {
 };
 
 
+/* push a  chunk into the queue
+ */
 int queue_push(
-                      t_iemnet_queue* const _this,
-                      t_iemnet_chunk* const data
-                      ) {
+	       t_iemnet_queue* const _this,
+	       t_iemnet_chunk* const data
+	       ) {
   t_node* tail;
   t_node* n=NULL;
-	int size=-1;
-		if(_this) {
-	size=_this->size;
-
-  if(NULL == data) return size;
-  //fprintf(stderr, "pushing %d bytes\n", data->size);
-
-  n=(t_node*)getbytes(sizeof(t_node));
-
-  n->next = 0;
-  n->data = data;
-  pthread_mutex_lock(&_this->mtx);
-  if (! (tail = _this->tail)) {
-    _this->head = n;
-  } else {
-    tail->next = n;
-  }
-  _this->tail = n;
+  int size=-1;
+  if(_this) {
+    size=_this->size;
+
+    if(NULL == data) return size;
+    //fprintf(stderr, "pushing %d bytes\n", data->size);
 
-  _this->size+=data->size;
-  size=_this->size;
+    n=(t_node*)getbytes(sizeof(t_node));
+
+    n->next = 0;
+    n->data = data;
+    pthread_mutex_lock(&_this->mtx);
+    if (! (tail = _this->tail)) {
+      _this->head = n;
+    } else {
+      tail->next = n;
+    }
+    _this->tail = n;
+
+    _this->size+=data->size;
+    size=_this->size;
 
-  //fprintf(stderr, "pushed %d bytes\n", data->size);
+    //fprintf(stderr, "pushed %d bytes\n", data->size);
 
-  pthread_mutex_unlock(&_this->mtx);
-  pthread_cond_signal(&_this->cond);
-		}
+    pthread_mutex_unlock(&_this->mtx);
+    pthread_cond_signal(&_this->cond);
+  }
   return size;
 }
 
+
+/* push a chunk from the queue
+ * if the queue is empty, this will block until 
+ *    something has been pushed
+ *   OR the queue is "done" (in which case NULL is returned)
+ */
 t_iemnet_chunk* queue_pop_block(
-                   t_iemnet_queue* const _this
-                   ) {
+				t_iemnet_queue* const _this
+				) {
 
   t_node* head=0;
   t_iemnet_chunk*data=0;
-	if(_this) {
-	pthread_mutex_lock(&_this->mtx);
-  while (! (head = _this->head)) {
-    if(_this->done) {
-      pthread_mutex_unlock(&_this->mtx);
-      return NULL;
-    }
-    else {
-      pthread_cond_wait(&_this->cond, &_this->mtx);
+  if(_this) {
+    pthread_mutex_lock(&_this->mtx);
+
+    /* wait until there is something in the queue or the "done" flag is set */
+    while (! (head = _this->head)) {
+      if(_this->done) {
+	pthread_mutex_unlock(&_this->mtx);
+	return NULL;
+      } else {
+	pthread_cond_wait(&_this->cond, &_this->mtx);
+      }
     }
-  }
 
-  if (! (_this->head = head->next)) {
-    _this->tail = 0;
-  }
-  if(head && head->data) {
-    _this->size-=head->data->size;
-  }
+    if (! (_this->head = head->next)) {
+      _this->tail = 0;
+    }
+    if(head && head->data) {
+      _this->size-=head->data->size;
+    }
 
-  pthread_mutex_unlock(&_this->mtx);
-  if(head) {
-    data=head->data;
-    freebytes(head, sizeof(t_node));
-    head=NULL;
+    pthread_mutex_unlock(&_this->mtx);
+    if(head) {
+      data=head->data;
+      freebytes(head, sizeof(t_node));
+      head=NULL;
+    }
   }
-	}
   return data;
 }
 
 t_iemnet_chunk* queue_pop_noblock(
-                   t_iemnet_queue* const _this
-                   ) {
+				  t_iemnet_queue* const _this
+				  ) {
   t_node* head=0;
   t_iemnet_chunk*data=0;
-		if(_this) {
-  pthread_mutex_lock(&_this->mtx);
-  if (! (head = _this->head)) {
-    // empty head
-    pthread_mutex_unlock(&_this->mtx);
-    return NULL;
-  }
-  if (! (_this->head = head->next)) {
-    _this->tail = 0;
-  }
-  if(head && head->data) {
-    _this->size-=head->data->size;
-  }
+  if(_this) {
+    pthread_mutex_lock(&_this->mtx);
+    if (! (head = _this->head)) {
+      // empty head
+      pthread_mutex_unlock(&_this->mtx);
+      return NULL;
+    }
+    if (! (_this->head = head->next)) {
+      _this->tail = 0;
+    }
+    if(head && head->data) {
+      _this->size-=head->data->size;
+    }
 
-  pthread_mutex_unlock(&_this->mtx);
-  if(head) {
-    data=head->data;
-    freebytes(head, sizeof(t_node));
-    head=NULL;
+    pthread_mutex_unlock(&_this->mtx);
+    if(head) {
+      data=head->data;
+      freebytes(head, sizeof(t_node));
+      head=NULL;
+    }
   }
-		}
   return data;
 }