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+/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult 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 */
+
+#ifdef __GNUC__
+#pragma implementation /* gcc: Class implementation */
+#endif
+
+#include <global.h>
+#include <my_sys.h>
+#include "cache_manager.h"
+
+/*
+ cache_manager.cc
+ -----------------------------------------------------------------------
+ The cache_manager class manages a number of blocks (which are allocatable
+ units of memory).
+ -----------------------------------------------------------------------
+*/
+
+#define HEADER_LENGTH ALIGN_SIZE(8)
+#define SUFFIX_LENGTH 4
+
+#define ALLOC_MASK 0x3FFFFFFFL
+#define FREE_BIT (1L << 31)
+#define LOCK_BIT (1L << 30)
+#define SMALLEST_BLOCK 32
+
+
+
+/*
+** Internal Methods
+** --------------------
+*/
+
+
+/* list manipulation methods */
+void *cache_manager::init_list(void)
+{
+
+return;
+}
+
+
+void *cache_manager::link_into_abs(void *ptr)
+{
+ for (int i(0); (*abs_list)[i] != NULL; i++);
+
+ (*abs_list)[i] = ptr;
+
+ return (abs_list)[i]; // ???
+}
+
+
+
+bool *cache_manager::unlink_from_abs(void *ptr)
+{
+ (*ptr) = NULL;
+
+return;
+}
+
+
+
+/* memory allocation methods */
+void *cache_manager::find_in_llist(uint)
+{
+
+return;
+}
+
+
+void cache_manager::defrag(void)
+{
+ printf("Defragging: ..........");
+
+ return;
+}
+
+
+
+/*
+** Public Methods
+** ------------------
+*/
+
+cache_manager::cache_manager(uint size)
+{
+ base_ptr = my_malloc(size, MY_WME); /* MY_WME = write mesg on err */
+
+ return;
+}
+
+
+cache_manager::~cache_manager(void)
+{
+ free(base_ptr);
+ delete base_ptr;
+
+ return;
+}
+
+
+void *cache_manager::alloc(uint size)
+{
+ void *llist;
+ void *abs_ptr;
+
+ size=ALIGN_SIZE(size+HEADER_LENGTH+SUFFIX_LENGTH);
+ if (!(llist = find_in_llist(size)))
+ {
+ //defrag();
+ if (!(llist = find_in_llist(size)))
+ return 0; /* return null pointer, buffer exhausted! */
+ }
+ size_of_found_block=int4korr((char*) llist) & ALLOC_MASK;
+ // if (size_of_found_block < SMALLEST_BLOCK)
+
+ abs_ptr = link_into_abs(llist);
+ return abs_ptr;
+}
+
+
+void cache_manager::dealloc(void)
+{
+ printf("Deallocating: ..........\n");
+
+ return;
+}
+
+
+
+void cache_manager::clear(void)
+{
+ // reset the internal linked list, forgetting all pointers to mem blks
+
+ return;
+}