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Diffstat (limited to 'storage/innodb_plugin/include/ha0storage.ic')
-rw-r--r-- | storage/innodb_plugin/include/ha0storage.ic | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/storage/innodb_plugin/include/ha0storage.ic b/storage/innodb_plugin/include/ha0storage.ic new file mode 100644 index 00000000000..5acbf82f005 --- /dev/null +++ b/storage/innodb_plugin/include/ha0storage.ic @@ -0,0 +1,148 @@ +/***************************************************************************** + +Copyright (c) 2007, 2009, Innobase Oy. All Rights Reserved. + +This program is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free Software +Foundation; version 2 of the License. + +This program is distributed in the hope that it will be useful, but WITHOUT +ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS +FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. + +You should have received a copy of the GNU General Public License along with +this program; if not, write to the Free Software Foundation, Inc., 59 Temple +Place, Suite 330, Boston, MA 02111-1307 USA + +*****************************************************************************/ + +/**************************************************//** +@file include/ha0storage.ic +Hash storage. +Provides a data structure that stores chunks of data in +its own storage, avoiding duplicates. + +Created September 24, 2007 Vasil Dimov +*******************************************************/ + +#include "univ.i" +#include "ha0storage.h" +#include "hash0hash.h" +#include "mem0mem.h" + +/** Hash storage for strings */ +struct ha_storage_struct { + mem_heap_t* heap; /*!< memory heap from which memory is + allocated */ + hash_table_t* hash; /*!< hash table used to avoid + duplicates */ +}; + +/** Objects of this type are stored in ha_storage_t */ +typedef struct ha_storage_node_struct ha_storage_node_t; +/** Objects of this type are stored in ha_storage_struct */ +struct ha_storage_node_struct { + ulint data_len;/*!< length of the data */ + const void* data; /*!< pointer to data */ + ha_storage_node_t* next; /*!< next node in hash chain */ +}; + +/*******************************************************************//** +Creates a hash storage. If any of the parameters is 0, then a default +value is used. +@return own: hash storage */ +UNIV_INLINE +ha_storage_t* +ha_storage_create( +/*==============*/ + ulint initial_heap_bytes, /*!< in: initial heap's size */ + ulint initial_hash_cells) /*!< in: initial number of cells + in the hash table */ +{ + ha_storage_t* storage; + mem_heap_t* heap; + + if (initial_heap_bytes == 0) { + + initial_heap_bytes = HA_STORAGE_DEFAULT_HEAP_BYTES; + } + + if (initial_hash_cells == 0) { + + initial_hash_cells = HA_STORAGE_DEFAULT_HASH_CELLS; + } + + /* we put "storage" within "storage->heap" */ + + heap = mem_heap_create(sizeof(ha_storage_t) + + initial_heap_bytes); + + storage = (ha_storage_t*) mem_heap_alloc(heap, + sizeof(ha_storage_t)); + + storage->heap = heap; + storage->hash = hash_create(initial_hash_cells); + + return(storage); +} + +/*******************************************************************//** +Empties a hash storage, freeing memory occupied by data chunks. +This invalidates any pointers previously returned by ha_storage_put(). +The hash storage is not invalidated itself and can be used again. */ +UNIV_INLINE +void +ha_storage_empty( +/*=============*/ + ha_storage_t** storage) /*!< in/out: hash storage */ +{ + ha_storage_t temp_storage; + + temp_storage.heap = (*storage)->heap; + temp_storage.hash = (*storage)->hash; + + hash_table_clear(temp_storage.hash); + mem_heap_empty(temp_storage.heap); + + *storage = (ha_storage_t*) mem_heap_alloc(temp_storage.heap, + sizeof(ha_storage_t)); + + (*storage)->heap = temp_storage.heap; + (*storage)->hash = temp_storage.hash; +} + +/*******************************************************************//** +Frees a hash storage and everything it contains, it cannot be used after +this call. +This invalidates any pointers previously returned by ha_storage_put(). */ +UNIV_INLINE +void +ha_storage_free( +/*============*/ + ha_storage_t* storage) /*!< in, own: hash storage */ +{ + /* order is important because the pointer storage->hash is + within the heap */ + hash_table_free(storage->hash); + mem_heap_free(storage->heap); +} + +/*******************************************************************//** +Gets the size of the memory used by a storage. +@return bytes used */ +UNIV_INLINE +ulint +ha_storage_get_size( +/*================*/ + const ha_storage_t* storage) /*!< in: hash storage */ +{ + ulint ret; + + ret = mem_heap_get_size(storage->heap); + + /* this assumes hash->heap and hash->heaps are NULL */ + ret += sizeof(hash_table_t); + ret += sizeof(hash_cell_t) * hash_get_n_cells(storage->hash); + + return(ret); +} |