Commit 9eb88fde authored by Michael Niedermayer's avatar Michael Niedermayer
Browse files

AVL tree

Originally committed as revision 7031 to svn://svn.ffmpeg.org/ffmpeg/trunk
parent 8fc433b4
......@@ -15,6 +15,7 @@ OBJS= mathematics.o \
log.o \
mem.o \
fifo.o \
tree.o \
HEADERS = avutil.h common.h mathematics.h integer.h rational.h \
intfloat_readwrite.h md5.h adler32.h log.h fifo.h
......
/*
* copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "common.h"
#include "log.h"
#include "tree.h"
typedef struct AVTreeNode{
struct AVTreeNode *child[2];
void *elem;
int state;
}AVTreeNode;
void *av_tree_find(const AVTreeNode *t, void *key, int (*cmp)(void *key, const void *b), void *next[2]){
if(t){
unsigned int v= cmp(t->elem, key);
if(v){
if(next) next[(v>>31)^1]= t->elem;
return av_tree_find(t->child[v>>31], key, cmp, next);
}else{
return t->elem;
}
}
return NULL;
}
void *av_tree_insert(AVTreeNode **tp, void *key, int (*cmp)(void *key, const void *b)){
AVTreeNode *t= *tp;
if(t){
unsigned int v= cmp(t->elem, key);
if(v){
int i= v>>31;
AVTreeNode **child= &t->child[i];
void *ret= av_tree_insert(child, key, cmp);
if(!ret){
t->state -= ((int)v>>31)|1;
if(!(t->state&1)){
if(t->state){
if((*child)->state*2 == t->state){
*tp= *child;
*child= (*child)->child[i^1];
(*tp)->child[i^1]= t;
t->state= 0;
}else{
*tp= (*child)->child[i^1];
(*child)->child[i^1]= (*tp)->child[i];
(*tp)->child[i]= *child;
*child= (*tp)->child[i^1];
(*tp)->child[i^1]= t;
i= (*tp)->state > 0;
(*tp)->child[i ]->state= 0;
(*tp)->child[i^1]->state= -(*tp)->state;
}
(*tp)->state=0;
}
return key;
}
}
return ret;
}else{
return t->elem;
}
}else{
*tp= av_mallocz(sizeof(AVTreeNode));
(*tp)->elem= key;
return NULL;
}
}
void av_tree_destroy(AVTreeNode *t){
av_tree_destroy(t->child[0]);
av_tree_destroy(t->child[1]);
av_free(t);
}
#if 0
void av_tree_enumerate(AVTreeNode *t, void *opaque, int (*f)(void *opaque, void *elem)){
f(opaque, t->elem);
av_tree_enumerate(t->child[0], opaque, f);
av_tree_enumerate(t->child[1], opaque, f);
}
#endif
#ifdef TEST
static int check(AVTreeNode *t){
if(t){
int left= check(t->child[0]);
int right= check(t->child[1]);
if(left>999 || right>999)
return 1000;
if(right - left != t->state)
return 1000;
if(t->state>1 || t->state<-1)
return 1000;
return FFMAX(left, right)+1;
}
return 0;
}
static void print(AVTreeNode *t, int depth){
int i;
for(i=0; i<depth*4; i++) av_log(NULL, AV_LOG_ERROR, " ");
if(t){
av_log(NULL, AV_LOG_ERROR, "Node %p %2d %4d\n", t, t->state, t->elem);
print(t->child[0], depth+1);
print(t->child[1], depth+1);
}else
av_log(NULL, AV_LOG_ERROR, "NULL\n");
}
int cmp(const void *a, const void *b){
return a-b;
}
int main(){
int i,j,k;
AVTreeNode *root= av_mallocz(sizeof(AVTreeNode));
for(i=0; i<10000; i++){
int j= (random()%863294);
if(check(root) > 999){
av_log(NULL, AV_LOG_ERROR, "FATAL error %d\n", i);
print(root, 0);
return -1;
}
av_log(NULL, AV_LOG_ERROR, "inserting %4d\n", j);
av_tree_insert(&root, (void*)(j+1), cmp);
}
return 0;
}
#endif
/*
* copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef TREE_H
#define TREE_H
struct AVTreeNode;
void *av_tree_find(const struct AVTreeNode *t, void *key, int (*cmp)(void *key, const void *b), void *next[2]);
void *av_tree_insert(struct AVTreeNode **tp, void *key, int (*cmp)(void *key, const void *b));
void av_tree_destroy(struct AVTreeNode *t);
#endif /* TREE_H */
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