diff options
| author | Tim Redfern <tim@eclectronics.org> | 2013-08-26 15:10:18 +0100 |
|---|---|---|
| committer | Tim Redfern <tim@eclectronics.org> | 2013-08-26 15:10:18 +0100 |
| commit | 150c9823e71a161e97003849cf8b2f55b21520bd (patch) | |
| tree | 3559c840cf403d1386708b2591d58f928c7b160d /ffmpeg1/libavutil/tree.c | |
| parent | b4b1e2630c95d5e6014463f7608d59dc2322a3b8 (diff) | |
adding ffmpeg specific version
Diffstat (limited to 'ffmpeg1/libavutil/tree.c')
| -rw-r--r-- | ffmpeg1/libavutil/tree.c | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/ffmpeg1/libavutil/tree.c b/ffmpeg1/libavutil/tree.c new file mode 100644 index 0000000..c6ae23d --- /dev/null +++ b/ffmpeg1/libavutil/tree.c @@ -0,0 +1,236 @@ +/* + * 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 "log.h" +#include "mem.h" +#include "tree.h" + +typedef struct AVTreeNode { + struct AVTreeNode *child[2]; + void *elem; + int state; +} AVTreeNode; + +const int av_tree_node_size = sizeof(AVTreeNode); + +struct AVTreeNode *av_tree_node_alloc(void) +{ + return av_mallocz(sizeof(struct 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(key, t->elem); + if (v) { + if (next) next[v >> 31] = t->elem; + return av_tree_find(t->child[(v >> 31) ^ 1], key, cmp, next); + } else { + if (next) { + av_tree_find(t->child[0], key, cmp, next); + av_tree_find(t->child[1], key, cmp, next); + } + return t->elem; + } + } + return NULL; +} + +void *av_tree_insert(AVTreeNode **tp, void *key, + int (*cmp)(void *key, const void *b), AVTreeNode **next) +{ + AVTreeNode *t = *tp; + if (t) { + unsigned int v = cmp(t->elem, key); + void *ret; + if (!v) { + if (*next) + return t->elem; + else if (t->child[0] || t->child[1]) { + int i = !t->child[0]; + void *next_elem[2]; + av_tree_find(t->child[i], key, cmp, next_elem); + key = t->elem = next_elem[i]; + v = -i; + } else { + *next = t; + *tp = NULL; + return NULL; + } + } + ret = av_tree_insert(&t->child[v >> 31], key, cmp, next); + if (!ret) { + int i = (v >> 31) ^ !!*next; + AVTreeNode **child = &t->child[i]; + t->state += 2 * i - 1; + + if (!(t->state & 1)) { + if (t->state) { + /* The following code is equivalent to + if((*child)->state*2 == -t->state) + rotate(child, i^1); + rotate(tp, i); + + with rotate(): + static void rotate(AVTreeNode **tp, int i) { + AVTreeNode *t= *tp; + + *tp= t->child[i]; + t->child[i]= t->child[i]->child[i^1]; + (*tp)->child[i^1]= t; + i= 4*t->state + 2*(*tp)->state + 12; + t ->state= ((0x614586 >> i) & 3)-1; + (*tp)->state= ((*tp)->state>>1) + ((0x400EEA >> i) & 3)-1; + } + but such a rotate function is both bigger and slower + */ + if (( *child )->state * 2 == -t->state) { + *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; + + (*tp)->child[0]->state = -((*tp)->state > 0); + (*tp)->child[1]->state = (*tp)->state < 0; + (*tp)->state = 0; + } else { + *tp = *child; + *child = (*child)->child[i ^ 1]; + (*tp)->child[i ^ 1] = t; + if ((*tp)->state) t->state = 0; + else t->state >>= 1; + (*tp)->state = -t->state; + } + } + } + if (!(*tp)->state ^ !!*next) + return key; + } + return ret; + } else { + *tp = *next; + *next = NULL; + if (*tp) { + (*tp)->elem = key; + return NULL; + } else + return key; + } +} + +void av_tree_destroy(AVTreeNode *t) +{ + if (t) { + av_tree_destroy(t->child[0]); + av_tree_destroy(t->child[1]); + av_free(t); + } +} + +void av_tree_enumerate(AVTreeNode *t, void *opaque, + int (*cmp)(void *opaque, void *elem), + int (*enu)(void *opaque, void *elem)) +{ + if (t) { + int v = cmp ? cmp(opaque, t->elem) : 0; + if (v >= 0) + av_tree_enumerate(t->child[0], opaque, cmp, enu); + if (v == 0) + enu(opaque, t->elem); + if (v <= 0) + av_tree_enumerate(t->child[1], opaque, cmp, enu); + } +} + +#ifdef TEST + +#include "common.h" +#include "lfg.h" + +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 %p\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"); +} + +static int cmp(void *a, const void *b) +{ + return (uint8_t *) a - (const uint8_t *) b; +} + +int main (void) +{ + int i; + void *k; + AVTreeNode *root = NULL, *node = NULL; + AVLFG prng; + + av_lfg_init(&prng, 1); + + for (i = 0; i < 10000; i++) { + intptr_t j = av_lfg_get(&prng) % 86294; + 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", (int)j); + if (!node) + node = av_tree_node_alloc(); + av_tree_insert(&root, (void *) (j + 1), cmp, &node); + + j = av_lfg_get(&prng) % 86294; + { + AVTreeNode *node2 = NULL; + av_log(NULL, AV_LOG_ERROR, "removing %4d\n", (int)j); + av_tree_insert(&root, (void *) (j + 1), cmp, &node2); + k = av_tree_find(root, (void *) (j + 1), cmp, NULL); + if (k) + av_log(NULL, AV_LOG_ERROR, "removal failure %d\n", i); + } + } + return 0; +} +#endif |
