From a175314c3e5827eb193872241446f2f8f5c9d33c Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 4 May 2024 20:07:14 +0200 Subject: Adding upstream version 1:10.5.12. Signed-off-by: Daniel Baumann --- storage/maria/ma_pagecaches.c | 104 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 104 insertions(+) create mode 100644 storage/maria/ma_pagecaches.c (limited to 'storage/maria/ma_pagecaches.c') diff --git a/storage/maria/ma_pagecaches.c b/storage/maria/ma_pagecaches.c new file mode 100644 index 00000000..fd5cd209 --- /dev/null +++ b/storage/maria/ma_pagecaches.c @@ -0,0 +1,104 @@ +/* Copyright (C) 2003-2007 MySQL AB + + 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA */ + +/* + Handling of multiple key caches + + The idea is to have a thread safe hash on the table name, + with a default key cache value that is returned if the table name is not in + the cache. +*/ + +#include "maria_def.h" +#include "ma_pagecache.h" +#include +#include +#include "../../mysys/my_safehash.h" + +/***************************************************************************** + Functions to handle the pagecache objects +*****************************************************************************/ + +/* Variable to store all key cache objects */ +static SAFE_HASH pagecache_hash; + + +my_bool multi_pagecache_init(void) +{ + return safe_hash_init(&pagecache_hash, 16, (uchar*) maria_pagecache); +} + + +void multi_pagecache_free(void) +{ + safe_hash_free(&pagecache_hash); +} + +/* + Get a key cache to be used for a specific table. + + SYNOPSIS + multi_pagecache_search() + key key to find (usually table path) + uint length Length of key. + def Default value if no key cache + + NOTES + This function is coded in such a way that we will return the + default key cache even if one never called multi_pagecache_init. + This will ensure that it works with old MyISAM clients. + + RETURN + key cache to use +*/ + +PAGECACHE *multi_pagecache_search(uchar *key, uint length, + PAGECACHE *def) +{ + if (!pagecache_hash.hash.records) + return def; + return (PAGECACHE*) safe_hash_search(&pagecache_hash, key, length, + (void*) def); +} + + +/* + Assosiate a key cache with a key + + + SYONOPSIS + multi_pagecache_set() + key key (path to table etc..) + length Length of key + pagecache cache to assococite with the table + + NOTES + This can be used both to insert a new entry and change an existing + entry +*/ + + +my_bool multi_pagecache_set(const uchar *key, uint length, + PAGECACHE *pagecache) +{ + return safe_hash_set(&pagecache_hash, key, length, (uchar*) pagecache); +} + + +void multi_pagecache_change(PAGECACHE *old_data, + PAGECACHE *new_data) +{ + safe_hash_change(&pagecache_hash, (uchar*) old_data, (uchar*) new_data); +} -- cgit v1.2.3