ha0ha.ic
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上传日期:2022-05-23
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文件大小:5k
- /************************************************************************
- The hash table with external chains
- (c) 1994-1997 Innobase Oy
- Created 8/18/1994 Heikki Tuuri
- *************************************************************************/
- #include "ut0rnd.h"
- #include "mem0mem.h"
- /***************************************************************
- Deletes a hash node. */
- void
- ha_delete_hash_node(
- /*================*/
- hash_table_t* table, /* in: hash table */
- ha_node_t* del_node); /* in: node to be deleted */
- /**********************************************************************
- Gets a hash node data. */
- UNIV_INLINE
- void*
- ha_node_get_data(
- /*=============*/
- /* out: pointer to the data */
- ha_node_t* node) /* in: hash chain node */
- {
- return(node->data);
- }
- /**********************************************************************
- Sets hash node data. */
- UNIV_INLINE
- void
- ha_node_set_data(
- /*=============*/
- ha_node_t* node, /* in: hash chain node */
- void* data) /* in: pointer to the data */
- {
- node->data = data;
- }
- /**********************************************************************
- Gets the next node in a hash chain. */
- UNIV_INLINE
- ha_node_t*
- ha_chain_get_next(
- /*==============*/
- /* out: next node, NULL if none */
- ha_node_t* node) /* in: hash chain node */
- {
- return(node->next);
- }
- /**********************************************************************
- Gets the first node in a hash chain. */
- UNIV_INLINE
- ha_node_t*
- ha_chain_get_first(
- /*===============*/
- /* out: first node, NULL if none */
- hash_table_t* table, /* in: hash table */
- ulint fold) /* in: fold value determining the chain */
- {
- return(hash_get_nth_cell(table, hash_calc_hash(fold, table))->node);
- }
- /*****************************************************************
- Looks for an element in a hash table. */
- UNIV_INLINE
- ha_node_t*
- ha_search(
- /*======*/
- /* out: pointer to the first hash table node
- in chain having the fold number, NULL if not
- found */
- hash_table_t* table, /* in: hash table */
- ulint fold) /* in: folded value of the searched data */
- {
- ha_node_t* node;
- #ifdef UNIV_SYNC_DEBUG
- ut_ad(!table->mutexes || mutex_own(hash_get_mutex(table, fold)));
- #endif /* UNIV_SYNC_DEBUG */
- node = ha_chain_get_first(table, fold);
- while (node) {
- if (node->fold == fold) {
- return(node);
- }
- node = ha_chain_get_next(node);
- }
- return(NULL);
- }
- /*****************************************************************
- Looks for an element in a hash table. */
- UNIV_INLINE
- void*
- ha_search_and_get_data(
- /*===================*/
- /* out: pointer to the data of the first hash
- table node in chain having the fold number,
- NULL if not found */
- hash_table_t* table, /* in: hash table */
- ulint fold) /* in: folded value of the searched data */
- {
- ha_node_t* node;
- #ifdef UNIV_SYNC_DEBUG
- ut_ad(!table->mutexes || mutex_own(hash_get_mutex(table, fold)));
- #endif /* UNIV_SYNC_DEBUG */
- node = ha_chain_get_first(table, fold);
- while (node) {
- if (node->fold == fold) {
- return(node->data);
- }
- node = ha_chain_get_next(node);
- }
- return(NULL);
- }
- /*************************************************************
- Looks for an element when we know the pointer to the data. */
- UNIV_INLINE
- ha_node_t*
- ha_search_with_data(
- /*================*/
- /* out: pointer to the hash table node, NULL
- if not found in the table */
- hash_table_t* table, /* in: hash table */
- ulint fold, /* in: folded value of the searched data */
- void* data) /* in: pointer to the data */
- {
- ha_node_t* node;
- #ifdef UNIV_SYNC_DEBUG
- ut_ad(!table->mutexes || mutex_own(hash_get_mutex(table, fold)));
- #endif /* UNIV_SYNC_DEBUG */
- node = ha_chain_get_first(table, fold);
- while (node) {
- if (node->data == data) {
- return(node);
- }
- node = ha_chain_get_next(node);
- }
- return(NULL);
- }
- /*************************************************************
- Looks for an element when we know the pointer to the data, and deletes
- it from the hash table, if found. */
- UNIV_INLINE
- ibool
- ha_search_and_delete_if_found(
- /*==========================*/
- /* out: TRUE if found */
- hash_table_t* table, /* in: hash table */
- ulint fold, /* in: folded value of the searched data */
- void* data) /* in: pointer to the data */
- {
- ha_node_t* node;
- #ifdef UNIV_SYNC_DEBUG
- ut_ad(!table->mutexes || mutex_own(hash_get_mutex(table, fold)));
- #endif /* UNIV_SYNC_DEBUG */
- node = ha_search_with_data(table, fold, data);
- if (node) {
- ha_delete_hash_node(table, node);
- return(TRUE);
- }
- return(FALSE);
- }
- /*****************************************************************
- Reserves the necessary hash table mutex and inserts an entry into the hash
- table. */
- UNIV_INLINE
- ibool
- ha_insert_for_fold_mutex(
- /*=====================*/
- /* out: TRUE if succeed, FALSE if no more
- memory could be allocated */
- hash_table_t* table, /* in: hash table */
- ulint fold, /* in: folded value of data; if a node with
- the same fold value already exists, it is
- updated to point to the same data, and no new
- node is created! */
- void* data) /* in: data, must not be NULL */
- {
- ibool ret;
- hash_mutex_enter(table, fold);
- ret = ha_insert_for_fold(table, fold, data);
- hash_mutex_exit(table, fold);
- return(ret);
- }