Pagecache integration for review.

storage/maria/unittest/ma_pagecache_single.c:
  Rename: storage/maria/unittest/mf_pagecache_single.c -> storage/maria/unittest/ma_pagecache_single.c
include/maria.h:
  Pagecache integration.
include/myisamchk.h:
  Pagecache integration.
include/pagecache.h:
  removed WRITE_NOW mode
  Pagecache parameters management.
mysys/Makefile.am:
  Safe hash procedures moved to the separate file.
  Pagecache moved to maria engine directory.
mysys/mf_keycaches.c:
  Safe hash procedures moved to the separate file.
sql/handler.cc:
  Pageccahe integration.
sql/handler.h:
  Pagecache integration.
sql/mysql_priv.h:
  pagecache integration
sql/mysqld.cc:
  pagecache integration
sql/set_var.cc:
  Pagecache integration.
sql/set_var.h:
  Pagecache integration.
storage/maria/Makefile.am:
  Pagecache integration and moving to maria engine directory.
storage/maria/ha_maria.cc:
  File changed on PAGECCAHE_FILE.
storage/maria/ma_bitmap.c:
  Pagecache integration.
storage/maria/ma_blockrec.c:
  Pagecache integration.
storage/maria/ma_check.c:
  File changed on PAGECCAHE_FILE.
  Pagecache integration.
storage/maria/ma_close.c:
  File changed on PAGECCAHE_FILE.
storage/maria/ma_delete_all.c:
  File changed on PAGECCAHE_FILE.
storage/maria/ma_dynrec.c:
  File changed on PAGECCAHE_FILE.
storage/maria/ma_extra.c:
  File changed on PAGECCAHE_FILE.
storage/maria/ma_info.c:
  File changed on PAGECCAHE_FILE.
storage/maria/ma_keycache.c:
  Pagecache integration.
storage/maria/ma_locking.c:
  File changed on PAGECCAHE_FILE.
storage/maria/ma_loghandler.c:
  Assert added.
storage/maria/ma_loghandler.h:
  extern specifier added.
storage/maria/ma_open.c:
  Pagecache integration.
  File changed on PAGECCAHE_FILE.
storage/maria/ma_packrec.c:
  File changed on PAGECCAHE_FILE.
storage/maria/ma_page.c:
  Pagecache integration.
storage/maria/ma_pagecache.c:
  Pagecache renamed and moved to the maria directory.
  BLOCK_* defines renamed to avoid conflict with BLOCK_ERROR defined in maria_def.h
storage/maria/ma_panic.c:
  File changed on PAGECCAHE_FILE.
storage/maria/ma_preload.c:
  Pagecache integration.
  File changed on PAGECCAHE_FILE.
storage/maria/ma_static.c:
  Pagecache integration.
storage/maria/ma_test1.c:
  Pagecache integration.
storage/maria/ma_test2.c:
  Pagecache integration.
storage/maria/ma_test3.c:
  Pagecache integration.
storage/maria/ma_write.c:
  File changed on PAGECCAHE_FILE.
storage/maria/maria_chk.c:
  Pagecache integration.
  File changed on PAGECCAHE_FILE.
storage/maria/maria_def.h:
  Pagecache integration.
  File changed on PAGECCAHE_FILE.
storage/maria/maria_ftdump.c:
  Pagecache integration.
storage/maria/maria_pack.c:
  File changed on PAGECCAHE_FILE.
storage/maria/unittest/Makefile.am:
  Pagecache moved to the maria directory.
storage/maria/unittest/ma_pagecache_consist.c:
  fixed using uninitialized variable
storage/maria/ma_pagecaches.c:
  New BitKeeper file ``storage/maria/ma_pagecaches.c''
mysys/my_safehash.h:
  New BitKeeper file ``mysys/my_safehash.h''

mysys/my_safehash.h

@@ -0,0 +1,58 @@
+/* Copyright (C) 2003 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; either version 2 of the License, or
+   (at your option) any later version.
+
+   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 */
+
+/*
+  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 <hash.h>
+
+/*
+  Struct to store a key and pointer to object
+*/
+
+typedef struct st_safe_hash_entry
+{
+  byte *key;
+  uint length;
+  byte *data;
+  struct st_safe_hash_entry *next, **prev;
+} SAFE_HASH_ENTRY;
+
+
+typedef struct st_safe_hash_with_default
+{
+#ifdef THREAD
+  rw_lock_t mutex;
+#endif
+  HASH hash;
+  byte *default_value;
+  SAFE_HASH_ENTRY *root;
+} SAFE_HASH;
+
+
+my_bool safe_hash_init(SAFE_HASH *hash, uint elements,
+                       byte *default_value);
+void safe_hash_free(SAFE_HASH *hash);
+byte *safe_hash_search(SAFE_HASH *hash, const byte *key, uint length,
+                       byte *def);
+my_bool safe_hash_set(SAFE_HASH *hash, const byte *key, uint length,
+                      byte *data);
+void safe_hash_change(SAFE_HASH *hash, byte *old_data, byte *new_data);