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-rw-r--r--libcurl/src/lib/splay.c288
1 files changed, 0 insertions, 288 deletions
diff --git a/libcurl/src/lib/splay.c b/libcurl/src/lib/splay.c
deleted file mode 100644
index 6f8227e..0000000
--- a/libcurl/src/lib/splay.c
+++ /dev/null
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-/***************************************************************************
- * _ _ ____ _
- * Project ___| | | | _ \| |
- * / __| | | | |_) | |
- * | (__| |_| | _ <| |___
- * \___|\___/|_| \_\_____|
- *
- * Copyright (C) 1997 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
- *
- * This software is licensed as described in the file COPYING, which
- * you should have received as part of this distribution. The terms
- * are also available at http://curl.haxx.se/docs/copyright.html.
- *
- * You may opt to use, copy, modify, merge, publish, distribute and/or sell
- * copies of the Software, and permit persons to whom the Software is
- * furnished to do so, under the terms of the COPYING file.
- *
- * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
- * KIND, either express or implied.
- *
- ***************************************************************************/
-
-#include "curl_setup.h"
-
-#include "splay.h"
-
-/*
- * This macro compares two node keys i and j and returns:
- *
- * negative value: when i is smaller than j
- * zero : when i is equal to j
- * positive when : when i is larger than j
- */
-#define compare(i,j) Curl_splaycomparekeys((i),(j))
-
-/*
- * Splay using the key i (which may or may not be in the tree.) The starting
- * root is t.
- */
-CURL_STATIC struct Curl_tree *Curl_splay(struct timeval i,
- struct Curl_tree *t)
-{
- struct Curl_tree N, *l, *r, *y;
- long comp;
-
- if(t == NULL)
- return t;
- N.smaller = N.larger = NULL;
- l = r = &N;
-
- for(;;) {
- comp = compare(i, t->key);
- if(comp < 0) {
- if(t->smaller == NULL)
- break;
- if(compare(i, t->smaller->key) < 0) {
- y = t->smaller; /* rotate smaller */
- t->smaller = y->larger;
- y->larger = t;
- t = y;
- if(t->smaller == NULL)
- break;
- }
- r->smaller = t; /* link smaller */
- r = t;
- t = t->smaller;
- }
- else if(comp > 0) {
- if(t->larger == NULL)
- break;
- if(compare(i, t->larger->key) > 0) {
- y = t->larger; /* rotate larger */
- t->larger = y->smaller;
- y->smaller = t;
- t = y;
- if(t->larger == NULL)
- break;
- }
- l->larger = t; /* link larger */
- l = t;
- t = t->larger;
- }
- else
- break;
- }
-
- l->larger = t->smaller; /* assemble */
- r->smaller = t->larger;
- t->smaller = N.larger;
- t->larger = N.smaller;
-
- return t;
-}
-
-/* Insert key i into the tree t. Return a pointer to the resulting tree or
- * NULL if something went wrong.
- *
- * @unittest: 1309
- */
-CURL_STATIC struct Curl_tree *Curl_splayinsert(struct timeval i,
- struct Curl_tree *t,
- struct Curl_tree *node)
-{
- static const struct timeval KEY_NOTUSED = {-1, -1}; /* will *NEVER* appear */
-
- if(node == NULL)
- return t;
-
- if(t != NULL) {
- t = Curl_splay(i, t);
- if(compare(i, t->key)==0) {
- /* There already exists a node in the tree with the very same key. Build
- a linked list of nodes. We make the new 'node' struct the new master
- node and make the previous node the first one in the 'same' list. */
-
- node->same = t;
- node->key = i;
- node->smaller = t->smaller;
- node->larger = t->larger;
-
- t->smaller = node; /* in the sub node for this same key, we use the
- smaller pointer to point back to the master
- node */
-
- t->key = KEY_NOTUSED; /* and we set the key in the sub node to NOTUSED
- to quickly identify this node as a subnode */
-
- return node; /* new root node */
- }
- }
-
- if(t == NULL) {
- node->smaller = node->larger = NULL;
- }
- else if(compare(i, t->key) < 0) {
- node->smaller = t->smaller;
- node->larger = t;
- t->smaller = NULL;
-
- }
- else {
- node->larger = t->larger;
- node->smaller = t;
- t->larger = NULL;
- }
- node->key = i;
-
- node->same = NULL; /* no identical node (yet) */
- return node;
-}
-
-/* Finds and deletes the best-fit node from the tree. Return a pointer to the
- resulting tree. best-fit means the node with the given or lower key */
-CURL_STATIC struct Curl_tree *Curl_splaygetbest(struct timeval i,
- struct Curl_tree *t,
- struct Curl_tree **removed)
-{
- struct Curl_tree *x;
-
- if(!t) {
- *removed = NULL; /* none removed since there was no root */
- return NULL;
- }
-
- t = Curl_splay(i, t);
- if(compare(i, t->key) < 0) {
- /* too big node, try the smaller chain */
- if(t->smaller)
- t=Curl_splay(t->smaller->key, t);
- else {
- /* fail */
- *removed = NULL;
- return t;
- }
- }
-
- if(compare(i, t->key) >= 0) { /* found it */
- /* FIRST! Check if there is a list with identical keys */
- x = t->same;
- if(x) {
- /* there is, pick one from the list */
-
- /* 'x' is the new root node */
-
- x->key = t->key;
- x->larger = t->larger;
- x->smaller = t->smaller;
-
- *removed = t;
- return x; /* new root */
- }
-
- if(t->smaller == NULL) {
- x = t->larger;
- }
- else {
- x = Curl_splay(i, t->smaller);
- x->larger = t->larger;
- }
- *removed = t;
-
- return x;
- }
- else {
- *removed = NULL; /* no match */
- return t; /* It wasn't there */
- }
-}
-
-
-/* Deletes the very node we point out from the tree if it's there. Stores a
- * pointer to the new resulting tree in 'newroot'.
- *
- * Returns zero on success and non-zero on errors! TODO: document error codes.
- * When returning error, it does not touch the 'newroot' pointer.
- *
- * NOTE: when the last node of the tree is removed, there's no tree left so
- * 'newroot' will be made to point to NULL.
- *
- * @unittest: 1309
- */
-CURL_STATIC int Curl_splayremovebyaddr(struct Curl_tree *t,
- struct Curl_tree *removenode,
- struct Curl_tree **newroot)
-{
- static const struct timeval KEY_NOTUSED = {-1, -1}; /* will *NEVER* appear */
- struct Curl_tree *x;
-
- if(!t || !removenode)
- return 1;
-
- if(compare(KEY_NOTUSED, removenode->key) == 0) {
- /* Key set to NOTUSED means it is a subnode within a 'same' linked list
- and thus we can unlink it easily. The 'smaller' link of a subnode
- links to the parent node. */
- if(removenode->smaller == NULL)
- return 3;
-
- removenode->smaller->same = removenode->same;
- if(removenode->same)
- removenode->same->smaller = removenode->smaller;
-
- /* Ensures that double-remove gets caught. */
- removenode->smaller = NULL;
-
- /* voila, we're done! */
- *newroot = t; /* return the same root */
- return 0;
- }
-
- t = Curl_splay(removenode->key, t);
-
- /* First make sure that we got the same root node as the one we want
- to remove, as otherwise we might be trying to remove a node that
- isn't actually in the tree.
-
- We cannot just compare the keys here as a double remove in quick
- succession of a node with key != KEY_NOTUSED && same != NULL
- could return the same key but a different node. */
- if(t != removenode)
- return 2;
-
- /* Check if there is a list with identical sizes, as then we're trying to
- remove the root node of a list of nodes with identical keys. */
- x = t->same;
- if(x) {
- /* 'x' is the new root node, we just make it use the root node's
- smaller/larger links */
-
- x->key = t->key;
- x->larger = t->larger;
- x->smaller = t->smaller;
- }
- else {
- /* Remove the root node */
- if(t->smaller == NULL)
- x = t->larger;
- else {
- x = Curl_splay(removenode->key, t->smaller);
- x->larger = t->larger;
- }
- }
-
- *newroot = x; /* store new root pointer */
-
- return 0;
-}
-