src/util/tests/hash_table/collision.c

   1 /*
   2  * Copyright © 2012 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *    Eric Anholt <eric@anholt.net>
  25  */
  26
  27 #include <stdlib.h>
  28 #include <stdio.h>
  29 #include <string.h>
  30 #include <assert.h>
  31 #include "hash_table.h"
  32
  33 int
  34 main(int argc, char **argv)
  35 {
  36    struct hash_table *ht;
  37    const char *str1 = "test1";
  38    const char *str2 = "test2";
  39    const char *str3 = "test3";
  40    struct hash_entry *entry1, *entry2, *search_entry;
  41    uint32_t bad_hash = 5;
  42    int i;
  43
  44    ht = _mesa_hash_table_create(NULL, NULL, _mesa_key_string_equal);
  45
  46    /* Insert some items.  Inserting 3 items forces a rehash and the new
  47     * table size is big enough that we don't get rehashes later.
  48     */
  49    _mesa_hash_table_insert_pre_hashed(ht, bad_hash, str1, NULL);
  50    _mesa_hash_table_insert_pre_hashed(ht, bad_hash, str2, NULL);
  51    _mesa_hash_table_insert_pre_hashed(ht, bad_hash, str3, NULL);
  52
  53    entry1 = _mesa_hash_table_search_pre_hashed(ht, bad_hash, str1);
  54    assert(entry1->key == str1);
  55
  56    entry2 = _mesa_hash_table_search_pre_hashed(ht, bad_hash, str2);
  57    assert(entry2->key == str2);
  58
  59    /* Check that we can still find #1 after inserting #2 */
  60    entry1 = _mesa_hash_table_search_pre_hashed(ht, bad_hash, str1);
  61    assert(entry1->key == str1);
  62
  63    /* Remove the collided entry and look again. */
  64    _mesa_hash_table_remove(ht, entry1);
  65    entry2 = _mesa_hash_table_search_pre_hashed(ht, bad_hash, str2);
  66    assert(entry2->key == str2);
  67
  68    /* Try inserting #2 again and make sure it gets overwritten */
  69    _mesa_hash_table_insert_pre_hashed(ht, bad_hash, str2, NULL);
  70    entry2 = _mesa_hash_table_search_pre_hashed(ht, bad_hash, str2);
  71    hash_table_foreach(ht, search_entry) {
  72       assert(search_entry == entry2 || search_entry->key != str2);
  73    }
  74
  75    /* Put str1 back, then spam junk into the table to force a
  76     * resize and make sure we can still find them both.
  77     */
  78    _mesa_hash_table_insert_pre_hashed(ht, bad_hash, str1, NULL);
  79    for (i = 0; i < 100; i++) {
  80       char *key = malloc(10);
  81       sprintf(key, "spam%d", i);
  82       _mesa_hash_table_insert_pre_hashed(ht, _mesa_hash_string(key), key, NULL);
  83    }
  84    entry1 = _mesa_hash_table_search_pre_hashed(ht, bad_hash, str1);
  85    assert(entry1->key == str1);
  86    entry2 = _mesa_hash_table_search_pre_hashed(ht, bad_hash, str2);
  87    assert(entry2->key == str2);
  88
  89    _mesa_hash_table_destroy(ht, NULL);
  90
  91    return 0;
  92 }