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+/* Copyright (c) 2003, 2011, Oracle and/or its affiliates.
+ Copyright (c) 2010, 2011, Monty Program 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 St, 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 "mysys_priv.h"
+#include <keycache.h>
+#include <hash.h>
+#include <m_string.h>
+#include "my_safehash.h"
+
+/*****************************************************************************
+ Functions to handle the key cache objects
+*****************************************************************************/
+
+/* Variable to store all key cache objects */
+static SAFE_HASH key_cache_hash;
+
+
+my_bool multi_keycache_init(void)
+{
+ return safe_hash_init(&key_cache_hash, 16, (uchar*) dflt_key_cache);
+}
+
+
+void multi_keycache_free(void)
+{
+ safe_hash_free(&key_cache_hash);
+}
+
+/*
+ Get a key cache to be used for a specific table.
+
+ SYNOPSIS
+ multi_key_cache_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_keycache_init.
+ This will ensure that it works with old MyISAM clients.
+
+ RETURN
+ key cache to use
+*/
+
+KEY_CACHE *multi_key_cache_search(uchar *key, uint length,
+ KEY_CACHE *def)
+{
+ if (!key_cache_hash.hash.records)
+ return def;
+ return (KEY_CACHE*) safe_hash_search(&key_cache_hash, key, length,
+ (void*) def);
+}
+
+
+/*
+ Assosiate a key cache with a key
+
+
+ SYONOPSIS
+ multi_key_cache_set()
+ key key (path to table etc..)
+ length Length of key
+ key_cache 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_key_cache_set(const uchar *key, uint length,
+ KEY_CACHE *key_cache)
+{
+ return safe_hash_set(&key_cache_hash, key, length, (uchar*) key_cache);
+}
+
+
+void multi_key_cache_change(KEY_CACHE *old_data,
+ KEY_CACHE *new_data)
+{
+ safe_hash_change(&key_cache_hash, (uchar*) old_data, (uchar*) new_data);
+}
+
+