debug_mem.h

/*
 * Copyright (c) 1999, 2002, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/*
 * Debug Memory Manager
 *
 * - inits allocated memory to predefined byte to expose uninitialized variables
 * - fills freed memory with predefined byte to expose dangling pointers
 * - catches under/overwrites with 'guard' bytes around allocated blocks
 * - tags blocks with the file name and line number where they were allocated
 * - reports unfreed blocks to help find memory leaks
 *
 */

#if !defined(_DEBUGMEM_H)
#define _DEBUGMEM_H

#if defined(__cplusplus)
extern "C" {
#endif

#if defined(DEBUG)

#include "debug_util.h"

/* prototype for allocation callback function */
typedef void * (*DMEM_ALLOCFN)(size_t size);

/* prototype for deallocation callback function */
typedef void (*DMEM_FREEFN)(void * pointer);

/* prototype for pointer validation function */
typedef dbool_t (*DMEM_CHECKPTRFN)(void * ptr, size_t size);

/* Debug memory manager global state */
/* DO NOT REFERENCE this structure in code, it is only exported */
/* to ease it's use inside a source level debugger */
typedef struct DMemState {
    DMEM_ALLOCFN        pfnAlloc;       /* block allocate callback */
    DMEM_FREEFN         pfnFree;        /* block free callback */
    DMEM_CHECKPTRFN     pfnCheckPtr;    /* pointer validation callback */
    size_t              biggestBlock;   /* largest block allocated so far */
    size_t              maxHeap;        /* maximum size of the debug heap */
    size_t              totalHeapUsed;  /* total memory allocated so far */
    dbool_t             failNextAlloc;  /* whether the next allocation fails (automatically resets)*/
    int                 totalAllocs;    /* total number of allocations so far */
} DMemState;

/* Exported global var so you can view/change settings in the debugger */
extern const DMemState  * DMemStatePtr;

/* General memory manager functions */
extern void DMem_Initialize();
extern void DMem_Shutdown();
extern void * DMem_AllocateBlock(size_t size, const char * filename, int linenumber);
extern void DMem_FreeBlock(void *ptr);
extern void DMem_ReportLeaks();

/* Routines to customize behaviour with callbacks */
extern void DMem_SetAllocCallback( DMEM_ALLOCFN pfn );
extern void DMem_SetFreeCallback( DMEM_FREEFN pfn );
extern void DMem_SetCheckPtrCallback( DMEM_CHECKPTRFN pfn );
extern void DMem_DisableMutex();

#endif /* defined(DEBUG) */

#if defined(__cplusplus)
} /* extern "C" */
#endif

#endif /* _DEBUGMEM_H */