/* libs/corecg/SkMemory_stdlib.cpp
**
** Copyright 2006, The Android Open Source Project
**
** Licensed under the Apache License, Version 2.0 (the "License");
** you may not use this file except in compliance with the License.
** You may obtain a copy of the License at
**
** http://www.apache.org/licenses/LICENSE-2.0
**
** Unless required by applicable law or agreed to in writing, software
** distributed under the License is distributed on an "AS IS" BASIS,
** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
** See the License for the specific language governing permissions and
** limitations under the License.
*/
#include "SkTypes.h"
#include <stdio.h>
#include <stdlib.h>
#ifdef SK_DEBUG
#define SK_TAG_BLOCKS
// #define SK_TRACK_ALLOC // enable to see a printf for every alloc/free
// #define SK_CHECK_TAGS // enable to double-check debugging link list
#endif
#ifdef SK_TAG_BLOCKS
#include "SkThread.h"
// size this (as a multiple of 4) so that the total offset to the internal data
// is at least a multiple of 8 (since some clients of our malloc may require
// that.
static const char kBlockHeaderTag[] = { 's', 'k', 'i', 'a', '1', '2', '3', '4' };
static const char kBlockTrailerTag[] = { 'a', 'i', 'k', 's' };
#define kByteFill 0xCD
#define kDeleteFill 0xEF
static SkMutex& get_block_mutex() {
static SkMutex* gBlockMutex;
if (NULL == gBlockMutex) {
gBlockMutex = new SkMutex;
}
return *gBlockMutex;
}
static struct SkBlockHeader* gHeader;
struct SkBlockHeader {
SkBlockHeader* fNext;
#ifdef SK_CHECK_TAGS
SkBlockHeader** fTop; // set to verify in debugger that block was alloc'd / freed with same gHeader
SkBlockHeader* fPrevious; // set to see in debugger previous block when corruption happens
#endif
size_t fSize;
char fHeader[sizeof(kBlockHeaderTag)];
// data goes here. The offset to this point must be a multiple of 8
char fTrailer[sizeof(kBlockTrailerTag)];
void* add(size_t realSize)
{
SkAutoMutexAcquire ac(get_block_mutex());
InMutexValidate();
fNext = gHeader;
#ifdef SK_CHECK_TAGS
fTop = &gHeader;
fPrevious = NULL;
if (fNext != NULL)
fNext->fPrevious = this;
#endif
gHeader = this;
fSize = realSize;
memcpy(fHeader, kBlockHeaderTag, sizeof(kBlockHeaderTag));
void* result = fTrailer;
void* trailer = (char*)result + realSize;
memcpy(trailer, kBlockTrailerTag, sizeof(kBlockTrailerTag));
return result;
}
static void Dump()
{
SkAutoMutexAcquire ac(get_block_mutex());
InMutexValidate();
SkBlockHeader* header = gHeader;
int count = 0;
size_t size = 0;
while (header != NULL) {
char scratch[256];
char* pos = scratch;
size_t size = header->fSize;
int* data = (int*)(void*)header->fTrailer;
pos += sprintf(pos, "%p 0x%08zx (%7zd) ",
data, size, size);
size >>= 2;
size_t ints = size > 4 ? 4 : size;
size_t index;
for (index = 0; index < ints; index++)
pos += sprintf(pos, "0x%08x ", data[index]);
pos += sprintf(pos, " (");
for (index = 0; index < ints; index++)
pos += sprintf(pos, "%g ", data[index] / 65536.0f);
if (ints > 0)
--pos;
pos += sprintf(pos, ") \"");
size_t chars = size > 16 ? 16 : size;
char* chPtr = (char*) data;
for (index = 0; index < chars; index++) {
char ch = chPtr[index];
pos += sprintf(pos, "%c", ch >= ' ' && ch < 0x7f ? ch : '?');
}
pos += sprintf(pos, "\"");
SkDebugf("%s\n", scratch);
count++;
size += header->fSize;
header = header->fNext;
}
SkDebugf("--- count %d size 0x%08x (%zd) ---\n", count, size, size);
}
void remove() const
{
SkAutoMutexAcquire ac(get_block_mutex());
SkBlockHeader** findPtr = &gHeader;
do {
SkBlockHeader* find = *findPtr;
SkASSERT(find != NULL);
if (find == this) {
*findPtr = fNext;
break;
}
findPtr = &find->fNext;
} while (true);
InMutexValidate();
SkASSERT(memcmp(fHeader, kBlockHeaderTag, sizeof(kBlockHeaderTag)) == 0);
const char* trailer = fTrailer + fSize;
SkASSERT(memcmp(trailer, kBlockTrailerTag, sizeof(kBlockTrailerTag)) == 0);
}
static void Validate()
{
SkAutoMutexAcquire ac(get_block_mutex());
InMutexValidate();
}
private:
static void InMutexValidate()
{
SkBlockHeader* header = gHeader;
while (header != NULL) {
SkASSERT(memcmp(header->fHeader, kBlockHeaderTag, sizeof(kBlockHeaderTag)) == 0);
char* trailer = header->fTrailer + header->fSize;
SkASSERT(memcmp(trailer, kBlockTrailerTag, sizeof(kBlockTrailerTag)) == 0);
header = header->fNext;
}
}
};
void ValidateHeap();
void ValidateHeap()
{
SkBlockHeader::Validate();
}
#else
void ValidateHeap() {}
#endif
void sk_throw()
{
#ifdef ANDROID
fprintf(stderr, "throwing...\n");
#endif
SkASSERT(!"sk_throw");
abort();
}
void sk_out_of_memory(void)
{
#ifdef ANDROID
fprintf(stderr,"- out of memory in SGL -\n");
#endif
SkASSERT(!"sk_out_of_memory");
abort();
}
void* sk_malloc_throw(size_t size)
{
return sk_malloc_flags(size, SK_MALLOC_THROW);
}
void* sk_realloc_throw(void* addr, size_t size)
{
#ifdef SK_TAG_BLOCKS
ValidateHeap();
if (addr != NULL) {
SkBlockHeader* header = (SkBlockHeader*)
((char*)addr - SK_OFFSETOF(SkBlockHeader, fTrailer));
header->remove();
#ifdef SK_TRACK_ALLOC
printf("sk_realloc_throw %p oldSize=%zd\n", addr, header->fSize);
#endif
addr = header;
}
size_t realSize = size;
if (size)
size += sizeof(SkBlockHeader);
#endif
void* p = realloc(addr, size);
if (size == 0)
{
ValidateHeap();
return p;
}
if (p == NULL)
sk_throw();
#ifdef SK_TAG_BLOCKS
else
{
SkBlockHeader* header = (SkBlockHeader*) p;
p = header->add(realSize);
#ifdef SK_TRACK_ALLOC
printf("sk_realloc_throw %p size=%zd\n", p, realSize);
#endif
}
#endif
ValidateHeap();
return p;
}
void sk_free(void* p)
{
if (p)
{
ValidateHeap();
#ifdef SK_TAG_BLOCKS
SkBlockHeader* header = (SkBlockHeader*)
((char*)p - SK_OFFSETOF(SkBlockHeader, fTrailer));
header->remove();
#ifdef SK_TRACK_ALLOC
printf("sk_free %p size=%zd\n", p, header->fSize);
#endif
size_t size = header->fSize + sizeof(SkBlockHeader);
memset(header, kDeleteFill, size);
p = header;
#endif
ValidateHeap();
free(p);
ValidateHeap();
}
}
void* sk_malloc_flags(size_t size, unsigned flags)
{
ValidateHeap();
#ifdef SK_TAG_BLOCKS
size_t realSize = size;
size += sizeof(SkBlockHeader);
#endif
void* p = malloc(size);
if (p == NULL)
{
if (flags & SK_MALLOC_THROW)
sk_throw();
}
#ifdef SK_TAG_BLOCKS
else
{
SkBlockHeader* header = (SkBlockHeader*) p;
p = header->add(realSize);
memset(p, kByteFill, realSize);
#ifdef SK_TRACK_ALLOC
printf("sk_malloc_flags %p size=%zd\n", p, realSize);
#endif
}
#endif
ValidateHeap();
return p;
}