35425d1034
The reftable format includes support for an (OID => ref) map. This map can speed up visibility and reachability checks. In particular, various operations along the fetch/push path within Gerrit have ben sped up by using this structure. The map is constructed with help of a binary tree. Object IDs are hashes, so they are uniformly distributed. Hence, the tree does not attempt forced rebalancing. Signed-off-by: Han-Wen Nienhuys <hanwen@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
64 lines
1.2 KiB
C
64 lines
1.2 KiB
C
/*
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Copyright 2020 Google LLC
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Use of this source code is governed by a BSD-style
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license that can be found in the LICENSE file or at
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https://developers.google.com/open-source/licenses/bsd
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*/
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#include "tree.h"
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#include "basics.h"
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#include "system.h"
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struct tree_node *tree_search(void *key, struct tree_node **rootp,
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int (*compare)(const void *, const void *),
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int insert)
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{
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int res;
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if (*rootp == NULL) {
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if (!insert) {
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return NULL;
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} else {
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struct tree_node *n =
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reftable_calloc(sizeof(struct tree_node));
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n->key = key;
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*rootp = n;
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return *rootp;
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}
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}
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res = compare(key, (*rootp)->key);
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if (res < 0)
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return tree_search(key, &(*rootp)->left, compare, insert);
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else if (res > 0)
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return tree_search(key, &(*rootp)->right, compare, insert);
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return *rootp;
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}
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void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key),
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void *arg)
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{
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if (t->left) {
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infix_walk(t->left, action, arg);
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}
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action(arg, t->key);
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if (t->right) {
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infix_walk(t->right, action, arg);
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}
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}
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void tree_free(struct tree_node *t)
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{
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if (t == NULL) {
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return;
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}
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if (t->left) {
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tree_free(t->left);
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}
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if (t->right) {
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tree_free(t->right);
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}
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reftable_free(t);
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}
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