/*
* 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.
*/
#if defined(DEBUG)
#include "debug_util.h"
#define DMEM_MIN(a,b) (a) < (b) ? (a) : (b)
#define DMEM_MAX(a,b) (a) > (b) ? (a) : (b)
typedef char byte_t;
static const byte_t ByteInited = '\xCD';
static const byte_t ByteFreed = '\xDD';
static const byte_t ByteGuard = '\xFD';
enum {
MAX_LINENUM = 50000, /* I certainly hope we don't have source files bigger than this */
MAX_CHECK_BYTES = 27, /* max bytes to check at start of block */
MAX_GUARD_BYTES = 8, /* size of guard areas on either side of a block */
MAX_DECIMAL_DIGITS = 15
};
/* Debug Info Header to precede allocated block */
typedef struct MemoryBlockHeader {
char filename[FILENAME_MAX+1]; /* filename where alloc occurred */
int linenumber; /* line where alloc occurred */
size_t size; /* size of the allocation */
int order; /* the order the block was allocated in */
struct MemoryListLink * listEnter; /* pointer to the free list node */
byte_t guard[MAX_GUARD_BYTES]; /* guard area for underrun check */
} MemoryBlockHeader;
/* Tail to follow allocated block */
typedef struct MemoryBlockTail {
byte_t guard[MAX_GUARD_BYTES]; /* guard area overrun check */
} MemoryBlockTail;
/* Linked list of allocated memory blocks */
typedef struct MemoryListLink {
struct MemoryListLink * next;
MemoryBlockHeader * header;
int freed;
} MemoryListLink;
/**************************************************
* Global Data structures
*/
static DMemState DMemGlobalState;
extern const DMemState * DMemStatePtr = &DMemGlobalState;
static MemoryListLink MemoryList = {NULL,NULL,FALSE};
static dmutex_t DMemMutex = NULL;
/**************************************************/
/*************************************************
* Client callback invocation functions
*/
static void * DMem_ClientAllocate(size_t size) {
if (DMemGlobalState.pfnAlloc != NULL) {
return (*DMemGlobalState.pfnAlloc)(size);
}
return malloc(size);
}
static void DMem_ClientFree(void * ptr) {
if (DMemGlobalState.pfnFree != NULL) {
(*DMemGlobalState.pfnFree)(ptr);
}
free(ptr);
}
static dbool_t DMem_ClientCheckPtr(void * ptr, size_t size) {
if (DMemGlobalState.pfnCheckPtr != NULL) {
return (*DMemGlobalState.pfnCheckPtr)(ptr, size);
}
return ptr != NULL;
}
/**************************************************/
/*************************************************
* Debug Memory Manager implementation
*/
static MemoryListLink * DMem_TrackBlock(MemoryBlockHeader * header) {
MemoryListLink * link;
link = (MemoryListLink *)DMem_ClientAllocate(sizeof(MemoryListLink));
if (link != NULL) {
link->header = header;
link->header->listEnter = link;
link->next = MemoryList.next;
link->freed = FALSE;
MemoryList.next = link;
}
return link;
}
static int DMem_VerifyGuardArea(const byte_t * area) {
int nbyte;
for ( nbyte = 0; nbyte < MAX_GUARD_BYTES; nbyte++ ) {
if (area[nbyte] != ByteGuard) {
return FALSE;
}
}
return TRUE;
}
static void DMem_VerifyHeader(MemoryBlockHeader * header) {
DASSERTMSG( DMem_ClientCheckPtr(header, sizeof(MemoryBlockHeader)), "Invalid header" );
DASSERTMSG( DMem_VerifyGuardArea(header->guard), "Header corruption, possible underwrite" );
DASSERTMSG( header->linenumber > 0 && header->linenumber < MAX_LINENUM, "Header corruption, bad line number" );
DASSERTMSG( header->size <= DMemGlobalState.biggestBlock, "Header corruption, block size is too large");
DASSERTMSG( header->order <= DMemGlobalState.totalAllocs, "Header corruption, block order out of range");
}
static void DMem_VerifyTail(MemoryBlockTail * tail) {
DASSERTMSG( DMem_ClientCheckPtr(tail, sizeof(MemoryBlockTail)), "Tail corruption, invalid pointer");
DASSERTMSG( DMem_VerifyGuardArea(tail->guard), "Tail corruption, possible overwrite" );
}
static MemoryBlockHeader * DMem_VerifyBlock(void * memptr) {
MemoryBlockHeader * header;
MemoryBlockTail * tail;
/* check if the pointer is valid */
DASSERTMSG( DMem_ClientCheckPtr(memptr, 1), "Invalid pointer");
/* check if the block header is valid */
header = (MemoryBlockHeader *)((byte_t *)memptr - sizeof(MemoryBlockHeader));
DMem_VerifyHeader(header);
/* check that the memory itself is valid */
DASSERTMSG( DMem_ClientCheckPtr(memptr, DMEM_MIN(MAX_CHECK_BYTES,header->size)), "Block memory invalid" );
/* check that the pointer to the alloc list is valid */
DASSERTMSG( DMem_ClientCheckPtr(header->listEnter, sizeof(MemoryListLink)), "Header corruption, alloc list pointer invalid" );
/* check the tail of the block for overruns */
tail = (MemoryBlockTail *) ( (byte_t *)memptr + header->size );
DMem_VerifyTail(tail);
return header;
}
static MemoryBlockHeader * DMem_GetHeader(void * memptr) {
MemoryBlockHeader * header = DMem_VerifyBlock(memptr);
return header;
}
/*
* Should be called before any other DMem_XXX function
*/
void DMem_Initialize() {
DMemMutex = DMutex_Create();
DMutex_Enter(DMemMutex);
DMemGlobalState.pfnAlloc = NULL;
DMemGlobalState.pfnFree = NULL;
DMemGlobalState.pfnCheckPtr = NULL;
DMemGlobalState.biggestBlock = 0;
DMemGlobalState.maxHeap = INT_MAX;
DMemGlobalState.totalHeapUsed = 0;
DMemGlobalState.failNextAlloc = FALSE;
DMemGlobalState.totalAllocs = 0;
DMutex_Exit(DMemMutex);
}
void DMem_Shutdown() {
DMutex_Destroy(DMemMutex);
}
/*
* Allocates a block of memory, reserving extra space at the start and end of the
* block to store debug info on where the block was allocated, it's size, and
* 'guard' areas to catch overwrite/underwrite bugs
*/
void * DMem_AllocateBlock(size_t size, const char * filename, int linenumber) {
MemoryBlockHeader * header;
MemoryBlockTail * tail;
size_t debugBlockSize;
byte_t * memptr = NULL;
DMutex_Enter(DMemMutex);
if (DMemGlobalState.failNextAlloc) {
/* force an allocation failure if so ordered */
DMemGlobalState.failNextAlloc = FALSE; /* reset flag */
goto Exit;
}
/* allocate a block large enough to hold extra debug info */
debugBlockSize = sizeof(MemoryBlockHeader) + size + sizeof(MemoryBlockTail);
header = (MemoryBlockHeader *)DMem_ClientAllocate(debugBlockSize);
if (header == NULL) {
goto Exit;
}
/* add block to list of allocated memory */
header->listEnter = DMem_TrackBlock(header);
if ( header->listEnter == NULL ) {
goto Exit;
}
/* store size of requested block */
header->size = size;
/* update maximum block size */
DMemGlobalState.biggestBlock = DMEM_MAX(header->size, DMemGlobalState.biggestBlock);
/* update used memory total */
DMemGlobalState.totalHeapUsed += header->size;
/* store filename and linenumber where allocation routine was called */
strncpy(header->filename, filename, FILENAME_MAX);
header->linenumber = linenumber;
/* store the order the block was allocated in */
header->order = DMemGlobalState.totalAllocs++;
/* initialize memory to a recognizable 'inited' value */
memptr = (byte_t *)header + sizeof(MemoryBlockHeader);
memset(memptr, ByteInited, size);
/* put guard area before block */
memset(header->guard, ByteGuard, MAX_GUARD_BYTES);
/* put guard area after block */
tail = (MemoryBlockTail *)(memptr + size);
memset(tail->guard, ByteGuard, MAX_GUARD_BYTES);
Exit:
DMutex_Exit(DMemMutex);
return memptr;
}
/*
* Frees block of memory allocated with DMem_AllocateBlock
*/
void DMem_FreeBlock(void * memptr) {
MemoryBlockHeader * header;
DMutex_Enter(DMemMutex);
if ( memptr == NULL) {
goto Exit;
}
/* get the debug block header preceding the allocated memory */
header = DMem_GetHeader(memptr);
/* fill memory with recognizable 'freed' value */
memset(memptr, ByteFreed, header->size);
/* mark block as freed */
header->listEnter->freed = TRUE;
/* update used memory total */
DMemGlobalState.totalHeapUsed -= header->size;
Exit:
DMutex_Exit(DMemMutex);
}
static void DMem_DumpHeader(MemoryBlockHeader * header) {
char report[FILENAME_MAX+MAX_DECIMAL_DIGITS*3+1];
static const char * reportFormat =
"file: %s, line %d\n"
"size: %d bytes\n"
"order: %d\n"
"-------";
DMem_VerifyHeader(header);
sprintf(report, reportFormat, header->filename, header->linenumber, header->size, header->order);
DTRACE_PRINTLN(report);
}
/*
* Call this function at shutdown time to report any leaked blocks
*/
void DMem_ReportLeaks() {
MemoryListLink * link;
DMutex_Enter(DMemMutex);
/* Force memory leaks to be output regardless of trace settings */
DTrace_EnableFile(__FILE__, TRUE);
DTRACE_PRINTLN("--------------------------");
DTRACE_PRINTLN("Debug Memory Manager Leaks");
DTRACE_PRINTLN("--------------------------");
/* walk through allocated list and dump any blocks not marked as freed */
link = MemoryList.next;
while (link != NULL) {
if ( !link->freed ) {
DMem_DumpHeader(link->header);
}
link = link->next;
}
DMutex_Exit(DMemMutex);
}
void DMem_SetAllocCallback( DMEM_ALLOCFN pfn ) {
DMutex_Enter(DMemMutex);
DMemGlobalState.pfnAlloc = pfn;
DMutex_Exit(DMemMutex);
}
void DMem_SetFreeCallback( DMEM_FREEFN pfn ) {
DMutex_Enter(DMemMutex);
DMemGlobalState.pfnFree = pfn;
DMutex_Exit(DMemMutex);
}
void DMem_SetCheckPtrCallback( DMEM_CHECKPTRFN pfn ) {
DMutex_Enter(DMemMutex);
DMemGlobalState.pfnCheckPtr = pfn;
DMutex_Exit(DMemMutex);
}
void DMem_DisableMutex() {
DMemMutex = NULL;
}
#endif /* defined(DEBUG) */
/* The following line is only here to prevent compiler warnings
* on release (non-debug) builds
*/
static int dummyVariable = 0;