lighttpd
/
lighttpd1.4
2
0
Fork 0
Code Issues Releases Wiki Activity

[core] splaytree: splaytree_splay_nonnull() 

splaytree_splay_nonnull() for operation on non-null splay_tree

inline func splaytree_splay() to short-circuit if tree already splayed
This commit is contained in:
Glenn Strauss 2023-09-10 23:35:57 -04:00
parent 75070ba693
commit 7988a4b7ad
2 changed files with 19 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
src/algo_splaytree.c
View File

@ -60,10 +60,12 @@
/* Splay using the key i (which may or may not be in the tree.)
* The starting root is t, and the tree used is defined by rat
*/
splay_tree * splaytree_splay (splay_tree *t, int i) {
__attribute_noinline__
__attribute_nonnull__()
__attribute_returns_nonnull__
splay_tree * splaytree_splay_nonnull (splay_tree *t, int i) {
splay_tree N, *l, *r, *y;
if (t == NULL) return t;
N.left = N.right = NULL;
l = r = &N;
@ -111,7 +113,9 @@ splay_tree * splaytree_insert(splay_tree * t, int i, void *data) {
splay_tree * new;
if (t != NULL) {
t = splaytree_splay(t, i);
/*(caller likely already verified that entry does not exist,
* so skip splaytree_splay() short-circuit check)*/
t = splaytree_splay_nonnull(t, i);
if (i == t->key) {
return t; /* it's already there */
}
@ -137,13 +141,14 @@ splay_tree * splaytree_insert(splay_tree * t, int i, void *data) {
splay_tree * splaytree_delete(splay_tree *t, int i) {
/* Deletes i from the tree if it's there. */
/* Return a pointer to the resulting tree. */
t = splaytree_splay(t, i);
if (t != NULL)
t = splaytree_splay_nonnull(t, i);
if (t != NULL && i == t->key) { /* found it */
splay_tree * x;
if (t->left == NULL) {
x = t->right;
} else {
x = splaytree_splay(t->left, i);
x = splaytree_splay_nonnull(t->left, i);
x->right = t->right;
}
free(t);

10
src/algo_splaytree.h
View File

@ -8,8 +8,16 @@ typedef struct tree_node {
void *data;
} splay_tree;
__attribute_nonnull__()
__attribute_returns_nonnull__
splay_tree * splaytree_splay_nonnull (splay_tree *t, int key);
static inline splay_tree * splaytree_splay (splay_tree *t, int key);
static inline splay_tree * splaytree_splay (splay_tree *t, int key) {
if (t == NULL || key == t->key) return t;
return splaytree_splay_nonnull(t, key);
}
splay_tree * splaytree_splay (splay_tree *t, int key);
splay_tree * splaytree_insert(splay_tree *t, int key, void *data);
splay_tree * splaytree_delete(splay_tree *t, int key);