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127 lines
2.8 KiB
C
127 lines
2.8 KiB
C
/******************************************************
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The simple hash table utility
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(c) 1997 Innobase Oy
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Created 5/20/1997 Heikki Tuuri
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*******************************************************/
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#include "hash0hash.h"
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#ifdef UNIV_NONINL
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#include "hash0hash.ic"
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#endif
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#include "mem0mem.h"
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/****************************************************************
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Reserves the mutex for a fold value in a hash table. */
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void
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hash_mutex_enter(
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/*=============*/
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hash_table_t* table, /* in: hash table */
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ulint fold) /* in: fold */
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{
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ut_ad(table->magic_n == HASH_TABLE_MAGIC_N);
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mutex_enter(hash_get_mutex(table, fold));
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}
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/****************************************************************
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Releases the mutex for a fold value in a hash table. */
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void
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hash_mutex_exit(
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/*============*/
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hash_table_t* table, /* in: hash table */
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ulint fold) /* in: fold */
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{
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ut_ad(table->magic_n == HASH_TABLE_MAGIC_N);
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mutex_exit(hash_get_mutex(table, fold));
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}
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/*****************************************************************
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Creates a hash table with >= n array cells. The actual number of cells is
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chosen to be a prime number slightly bigger than n. */
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hash_table_t*
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hash_create(
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/*========*/
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/* out, own: created table */
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ulint n) /* in: number of array cells */
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{
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hash_cell_t* array;
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ulint prime;
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hash_table_t* table;
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ulint i;
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hash_cell_t* cell;
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prime = ut_find_prime(n);
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table = mem_alloc(sizeof(hash_table_t));
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array = ut_malloc(sizeof(hash_cell_t) * prime);
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table->adaptive = FALSE;
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table->array = array;
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table->n_cells = prime;
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table->n_mutexes = 0;
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table->mutexes = NULL;
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table->heaps = NULL;
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table->heap = NULL;
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#ifdef UNIV_DEBUG
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table->magic_n = HASH_TABLE_MAGIC_N;
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#endif /* UNIV_DEBUG */
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/* Initialize the cell array */
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for (i = 0; i < prime; i++) {
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cell = hash_get_nth_cell(table, i);
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cell->node = NULL;
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}
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return(table);
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}
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/*****************************************************************
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Frees a hash table. */
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void
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hash_table_free(
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/*============*/
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hash_table_t* table) /* in, own: hash table */
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{
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ut_ad(table->magic_n == HASH_TABLE_MAGIC_N);
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ut_a(table->mutexes == NULL);
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ut_free(table->array);
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mem_free(table);
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}
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/*****************************************************************
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Creates a mutex array to protect a hash table. */
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void
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hash_create_mutexes(
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/*================*/
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hash_table_t* table, /* in: hash table */
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ulint n_mutexes, /* in: number of mutexes, must be a
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power of 2 */
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ulint sync_level) /* in: latching order level of the
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mutexes: used in the debug version */
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{
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ulint i;
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ut_a(n_mutexes == ut_2_power_up(n_mutexes));
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ut_ad(table->magic_n == HASH_TABLE_MAGIC_N);
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table->mutexes = mem_alloc(n_mutexes * sizeof(mutex_t));
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for (i = 0; i < n_mutexes; i++) {
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mutex_create(table->mutexes + i);
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mutex_set_level(table->mutexes + i, sync_level);
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}
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table->n_mutexes = n_mutexes;
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}
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