[FFmpeg-cvslog] r11399 - in trunk: libavformat/nut.c libavutil/tree.c libavutil/tree.h

michael subversion
Fri Jan 4 18:52:17 CET 2008

Author: michael
Date: Fri Jan  4 18:52:16 2008
New Revision: 11399

Move *malloc() out of tree.c, that way the code can be used with
flat arrays which have lower overhead than millions of mallocd() elements.


Modified: trunk/libavformat/nut.c
--- trunk/libavformat/nut.c	(original)
+++ trunk/libavformat/nut.c	Fri Jan  4 18:52:16 2008
@@ -48,12 +48,15 @@ int ff_nut_sp_pts_cmp(syncpoint_t *a, sy
 void ff_nut_add_sp(NUTContext *nut, int64_t pos, int64_t back_ptr, int64_t ts){
-    syncpoint_t *sp2, *sp= av_mallocz(sizeof(syncpoint_t));
+    syncpoint_t *sp= av_mallocz(sizeof(syncpoint_t));
+    struct AVTreeNode *node= av_mallocz(av_tree_node_size);
     sp->pos= pos;
     sp->back_ptr= back_ptr;
     sp->ts= ts;
-    sp2= av_tree_insert(&nut->syncpoints, sp, ff_nut_sp_pos_cmp);
-    if(sp2 && sp2 != sp)
+    av_tree_insert(&nut->syncpoints, sp, ff_nut_sp_pos_cmp, &node);
+    if(node){
+        av_free(node);
+    }

Modified: trunk/libavutil/tree.c
--- trunk/libavutil/tree.c	(original)
+++ trunk/libavutil/tree.c	Fri Jan  4 18:52:16 2008
@@ -28,6 +28,8 @@ typedef struct AVTreeNode{
     int state;
+const int av_tree_node_size = sizeof(AVTreeNode);
 void *av_tree_find(const AVTreeNode *t, void *key, int (*cmp)(void *key, const void *b), void *next[2]){
         unsigned int v= cmp(t->elem, key);
@@ -45,14 +47,14 @@ void *av_tree_find(const AVTreeNode *t, 
     return NULL;
-void *av_tree_insert(AVTreeNode **tp, void *key, int (*cmp)(void *key, const void *b)){
+void *av_tree_insert(AVTreeNode **tp, void *key, int (*cmp)(void *key, const void *b), AVTreeNode **next){
     AVTreeNode *t= *tp;
         unsigned int v= cmp(t->elem, key);
             int i= v>>31;
             AVTreeNode **child= &t->child[i];
-            void *ret= av_tree_insert(child, key, cmp);
+            void *ret= av_tree_insert(child, key, cmp, next);
                 t->state -= ((int)v>>31)|1;
@@ -83,7 +85,7 @@ void *av_tree_insert(AVTreeNode **tp, vo
             return t->elem;
-        *tp= av_mallocz(sizeof(AVTreeNode));
+        *tp= *next; *next= NULL;
         (*tp)->elem= key;
         return NULL;

Modified: trunk/libavutil/tree.h
--- trunk/libavutil/tree.h	(original)
+++ trunk/libavutil/tree.h	Fri Jan  4 18:52:16 2008
@@ -28,6 +28,7 @@
 #define FFMPEG_TREE_H
 struct AVTreeNode;
+extern const int av_tree_node_size;
  * Finds an element.
@@ -46,13 +47,22 @@ void *av_tree_find(const struct AVTreeNo
  * @param rootp A pointer to a pointer to the root node of the tree. Note that
  *              the root node can change during insertions, this is required
  *              to keep the tree balanced.
+ * @param next AVTreeNode used for the inserted element, must be allocated and
+ *             zeroed by the user. And will be set to NULL if used by
+ *             av_tree_insert(). This allows the use of flat arrays, which have
+ *             lower overhead compared to many malloced elements.
+ *             You might want to define a function like:
+ *             void *tree_insert(struct AVTreeNode **rootp, void *key, int (*cmp)(void *key, const void *b), AVTreeNode **next){
+ *                 if(!*next) *next= av_mallocz(av_tree_node_size);
+ *                 return av_tree_insert(rootp, key, cmp, next);
+ *             }
  * @return If no insertion happened, the found element.
  *         If an insertion happened, then either key or NULL will be returned.
  *         Which one it is depends on the tree state and the implementation. You
  *         should make no assumptions that it's one or the other in the code.
-void *av_tree_insert(struct AVTreeNode **rootp, void *key, int (*cmp)(void *key, const void *b));
+void *av_tree_insert(struct AVTreeNode **rootp, void *key, int (*cmp)(void *key, const void *b), struct AVTreeNode **next);
 void av_tree_destroy(struct AVTreeNode *t);
 #endif /* FFMPEG_TREE_H */

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