| 1 | /* |
| 2 | * Copyright 2020 Google LLC |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style |
| 5 | * license that can be found in the LICENSE file or at |
| 6 | * https://developers.google.com/open-source/licenses/bsd |
| 7 | */ |
| 8 | |
| 9 | #include "system.h" |
| 10 | #include "tree.h" |
| 11 | |
| 12 | #include "basics.h" |
| 13 | |
| 14 | struct tree_node *tree_search(struct tree_node *tree, |
| 15 | void *key, |
| 16 | int (*compare)(const void *, const void *)) |
| 17 | { |
| 18 | int res; |
| 19 | if (!tree) |
| 20 | return NULL; |
| 21 | res = compare(key, tree->key); |
| 22 | if (res < 0) |
| 23 | return tree_search(tree->left, key, compare); |
| 24 | else if (res > 0) |
| 25 | return tree_search(tree->right, key, compare); |
| 26 | return tree; |
| 27 | } |
| 28 | |
| 29 | struct tree_node *tree_insert(struct tree_node **rootp, |
| 30 | void *key, |
| 31 | int (*compare)(const void *, const void *)) |
| 32 | { |
| 33 | int res; |
| 34 | |
| 35 | if (!*rootp) { |
| 36 | struct tree_node *n; |
| 37 | |
| 38 | REFTABLE_CALLOC_ARRAY(n, 1); |
| 39 | if (!n) |
| 40 | return NULL; |
| 41 | |
| 42 | n->key = key; |
| 43 | *rootp = n; |
| 44 | return *rootp; |
| 45 | } |
| 46 | |
| 47 | res = compare(key, (*rootp)->key); |
| 48 | if (res < 0) |
| 49 | return tree_insert(&(*rootp)->left, key, compare); |
| 50 | else if (res > 0) |
| 51 | return tree_insert(&(*rootp)->right, key, compare); |
| 52 | return *rootp; |
| 53 | } |
| 54 | |
| 55 | void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key), |
| 56 | void *arg) |
| 57 | { |
| 58 | if (t->left) |
| 59 | infix_walk(t->left, action, arg); |
| 60 | action(arg, t->key); |
| 61 | if (t->right) |
| 62 | infix_walk(t->right, action, arg); |
| 63 | } |
| 64 | |
| 65 | void tree_free(struct tree_node *t) |
| 66 | { |
| 67 | if (!t) |
| 68 | return; |
| 69 | if (t->left) |
| 70 | tree_free(t->left); |
| 71 | if (t->right) |
| 72 | tree_free(t->right); |
| 73 | reftable_free(t); |
| 74 | } |