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-rw-r--r--ffmpeg1/libavutil/tree.c236
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
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