From 9eb88fdeba5b72a84f192dee48ec420a57ca208d Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 14 Nov 2006 01:02:30 +0000 Subject: AVL tree Originally committed as revision 7031 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavutil/tree.c | 151 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 151 insertions(+) create mode 100644 libavutil/tree.c (limited to 'libavutil/tree.c') diff --git a/libavutil/tree.c b/libavutil/tree.c new file mode 100644 index 0000000000..aff749e791 --- /dev/null +++ b/libavutil/tree.c @@ -0,0 +1,151 @@ +/* + * copyright (c) 2006 Michael Niedermayer + * + * 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; istate, 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 -- cgit v1.2.3