/*
* Copyright (C) 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.
*/
//
// Provide access to a read-only asset.
//
#define LOG_TAG "asset"
//#define NDEBUG 0
#include <utils/Asset.h>
#include <utils/Atomic.h>
#include <utils/FileMap.h>
#include <utils/StreamingZipInflater.h>
#include <utils/ZipUtils.h>
#include <utils/ZipFileRO.h>
#include <utils/Log.h>
#include <utils/threads.h>
#include <string.h>
#include <memory.h>
#include <fcntl.h>
#include <errno.h>
#include <assert.h>
using namespace android;
#ifndef O_BINARY
# define O_BINARY 0
#endif
static Mutex gAssetLock;
static int32_t gCount = 0;
static Asset* gHead = NULL;
static Asset* gTail = NULL;
int32_t Asset::getGlobalCount()
{
AutoMutex _l(gAssetLock);
return gCount;
}
String8 Asset::getAssetAllocations()
{
AutoMutex _l(gAssetLock);
String8 res;
Asset* cur = gHead;
while (cur != NULL) {
if (cur->isAllocated()) {
res.append(" ");
res.append(cur->getAssetSource());
off_t size = (cur->getLength()+512)/1024;
char buf[64];
sprintf(buf, ": %dK\n", (int)size);
res.append(buf);
}
cur = cur->mNext;
}
return res;
}
Asset::Asset(void)
: mAccessMode(ACCESS_UNKNOWN)
{
AutoMutex _l(gAssetLock);
gCount++;
mNext = mPrev = NULL;
if (gTail == NULL) {
gHead = gTail = this;
} else {
mPrev = gTail;
gTail->mNext = this;
gTail = this;
}
//LOGI("Creating Asset %p #%d\n", this, gCount);
}
Asset::~Asset(void)
{
AutoMutex _l(gAssetLock);
gCount--;
if (gHead == this) {
gHead = mNext;
}
if (gTail == this) {
gTail = mPrev;
}
if (mNext != NULL) {
mNext->mPrev = mPrev;
}
if (mPrev != NULL) {
mPrev->mNext = mNext;
}
mNext = mPrev = NULL;
//LOGI("Destroying Asset in %p #%d\n", this, gCount);
}
/*
* Create a new Asset from a file on disk. There is a fair chance that
* the file doesn't actually exist.
*
* We can use "mode" to decide how we want to go about it.
*/
/*static*/ Asset* Asset::createFromFile(const char* fileName, AccessMode mode)
{
_FileAsset* pAsset;
status_t result;
off_t length;
int fd;
fd = open(fileName, O_RDONLY | O_BINARY);
if (fd < 0)
return NULL;
/*
* Under Linux, the lseek fails if we actually opened a directory. To
* be correct we should test the file type explicitly, but since we
* always open things read-only it doesn't really matter, so there's
* no value in incurring the extra overhead of an fstat() call.
*/
length = lseek(fd, 0, SEEK_END);
if (length < 0) {
::close(fd);
return NULL;
}
(void) lseek(fd, 0, SEEK_SET);
pAsset = new _FileAsset;
result = pAsset->openChunk(fileName, fd, 0, length);
if (result != NO_ERROR) {
delete pAsset;
return NULL;
}
pAsset->mAccessMode = mode;
return pAsset;
}
/*
* Create a new Asset from a compressed file on disk. There is a fair chance
* that the file doesn't actually exist.
*
* We currently support gzip files. We might want to handle .bz2 someday.
*/
/*static*/ Asset* Asset::createFromCompressedFile(const char* fileName,
AccessMode mode)
{
_CompressedAsset* pAsset;
status_t result;
off_t fileLen;
bool scanResult;
long offset;
int method;
long uncompressedLen, compressedLen;
int fd;
fd = open(fileName, O_RDONLY | O_BINARY);
if (fd < 0)
return NULL;
fileLen = lseek(fd, 0, SEEK_END);
if (fileLen < 0) {
::close(fd);
return NULL;
}
(void) lseek(fd, 0, SEEK_SET);
/* want buffered I/O for the file scan; must dup so fclose() is safe */
FILE* fp = fdopen(dup(fd), "rb");
if (fp == NULL) {
::close(fd);
return NULL;
}
unsigned long crc32;
scanResult = ZipUtils::examineGzip(fp, &method, &uncompressedLen,
&compressedLen, &crc32);
offset = ftell(fp);
fclose(fp);
if (!scanResult) {
LOGD("File '%s' is not in gzip format\n", fileName);
::close(fd);
return NULL;
}
pAsset = new _CompressedAsset;
result = pAsset->openChunk(fd, offset, method, uncompressedLen,
compressedLen);
if (result != NO_ERROR) {
delete pAsset;
return NULL;
}
pAsset->mAccessMode = mode;
return pAsset;
}
#if 0
/*
* Create a new Asset from part of an open file.
*/
/*static*/ Asset* Asset::createFromFileSegment(int fd, off_t offset,
size_t length, AccessMode mode)
{
_FileAsset* pAsset;
status_t result;
pAsset = new _FileAsset;
result = pAsset->openChunk(NULL, fd, offset, length);
if (result != NO_ERROR)
return NULL;
pAsset->mAccessMode = mode;
return pAsset;
}
/*
* Create a new Asset from compressed data in an open file.
*/
/*static*/ Asset* Asset::createFromCompressedData(int fd, off_t offset,
int compressionMethod, size_t uncompressedLen, size_t compressedLen,
AccessMode mode)
{
_CompressedAsset* pAsset;
status_t result;
pAsset = new _CompressedAsset;
result = pAsset->openChunk(fd, offset, compressionMethod,
uncompressedLen, compressedLen);
if (result != NO_ERROR)
return NULL;
pAsset->mAccessMode = mode;
return pAsset;
}
#endif
/*
* Create a new Asset from a memory mapping.
*/
/*static*/ Asset* Asset::createFromUncompressedMap(FileMap* dataMap,
AccessMode mode)
{
_FileAsset* pAsset;
status_t result;
pAsset = new _FileAsset;
result = pAsset->openChunk(dataMap);
if (result != NO_ERROR)
return NULL;
pAsset->mAccessMode = mode;
return pAsset;
}
/*
* Create a new Asset from compressed data in a memory mapping.
*/
/*static*/ Asset* Asset::createFromCompressedMap(FileMap* dataMap,
int method, size_t uncompressedLen, AccessMode mode)
{
_CompressedAsset* pAsset;
status_t result;
pAsset = new _CompressedAsset;
result = pAsset->openChunk(dataMap, method, uncompressedLen);
if (result != NO_ERROR)
return NULL;
pAsset->mAccessMode = mode;
return pAsset;
}
/*
* Do generic seek() housekeeping. Pass in the offset/whence values from
* the seek request, along with the current chunk offset and the chunk
* length.
*
* Returns the new chunk offset, or -1 if the seek is illegal.
*/
off_t Asset::handleSeek(off_t offset, int whence, off_t curPosn, off_t maxPosn)
{
off_t newOffset;
switch (whence) {
case SEEK_SET:
newOffset = offset;
break;
case SEEK_CUR:
newOffset = curPosn + offset;
break;
case SEEK_END:
newOffset = maxPosn + offset;
break;
default:
LOGW("unexpected whence %d\n", whence);
// this was happening due to an off_t size mismatch
assert(false);
return (off_t) -1;
}
if (newOffset < 0 || newOffset > maxPosn) {
LOGW("seek out of range: want %ld, end=%ld\n",
(long) newOffset, (long) maxPosn);
return (off_t) -1;
}
return newOffset;
}
/*
* ===========================================================================
* _FileAsset
* ===========================================================================
*/
/*
* Constructor.
*/
_FileAsset::_FileAsset(void)
: mStart(0), mLength(0), mOffset(0), mFp(NULL), mFileName(NULL), mMap(NULL), mBuf(NULL)
{
}
/*
* Destructor. Release resources.
*/
_FileAsset::~_FileAsset(void)
{
close();
}
/*
* Operate on a chunk of an uncompressed file.
*
* Zero-length chunks are allowed.
*/
status_t _FileAsset::openChunk(const char* fileName, int fd, off_t offset, size_t length)
{
assert(mFp == NULL); // no reopen
assert(mMap == NULL);
assert(fd >= 0);
assert(offset >= 0);
/*
* Seek to end to get file length.
*/
off_t fileLength;
fileLength = lseek(fd, 0, SEEK_END);
if (fileLength == (off_t) -1) {
// probably a bad file descriptor
LOGD("failed lseek (errno=%d)\n", errno);
return UNKNOWN_ERROR;
}
if ((off_t) (offset + length) > fileLength) {
LOGD("start (%ld) + len (%ld) > end (%ld)\n",
(long) offset, (long) length, (long) fileLength);
return BAD_INDEX;
}
/* after fdopen, the fd will be closed on fclose() */
mFp = fdopen(fd, "rb");
if (mFp == NULL)
return UNKNOWN_ERROR;
mStart = offset;
mLength = length;
assert(mOffset == 0);
/* seek the FILE* to the start of chunk */
if (fseek(mFp, mStart, SEEK_SET) != 0) {
assert(false);
}
mFileName = fileName != NULL ? strdup(fileName) : NULL;
return NO_ERROR;
}
/*
* Create the chunk from the map.
*/
status_t _FileAsset::openChunk(FileMap* dataMap)
{
assert(mFp == NULL); // no reopen
assert(mMap == NULL);
assert(dataMap != NULL);
mMap = dataMap;
mStart = -1; // not used
mLength = dataMap->getDataLength();
assert(mOffset == 0);
return NO_ERROR;
}
/*
* Read a chunk of data.
*/
ssize_t _FileAsset::read(void* buf, size_t count)
{
size_t maxLen;
size_t actual;
assert(mOffset >= 0 && mOffset <= mLength);
if (getAccessMode() == ACCESS_BUFFER) {
/*
* On first access, read or map the entire file. The caller has
* requested buffer access, either because they're going to be
* using the buffer or because what they're doing has appropriate
* performance needs and access patterns.
*/
if (mBuf == NULL)
getBuffer(false);
}
/* adjust count if we're near EOF */
maxLen = mLength - mOffset;
if (count > maxLen)
count = maxLen;
if (!count)
return 0;
if (mMap != NULL) {
/* copy from mapped area */
//printf("map read\n");
memcpy(buf, (char*)mMap->getDataPtr() + mOffset, count);
actual = count;
} else if (mBuf != NULL) {
/* copy from buffer */
//printf("buf read\n");
memcpy(buf, (char*)mBuf + mOffset, count);
actual = count;
} else {
/* read from the file */
//printf("file read\n");
if (ftell(mFp) != mStart + mOffset) {
LOGE("Hosed: %ld != %ld+%ld\n",
ftell(mFp), (long) mStart, (long) mOffset);
assert(false);
}
/*
* This returns 0 on error or eof. We need to use ferror() or feof()
* to tell the difference, but we don't currently have those on the
* device. However, we know how much data is *supposed* to be in the
* file, so if we don't read the full amount we know something is
* hosed.
*/
actual = fread(buf, 1, count, mFp);
if (actual == 0) // something failed -- I/O error?
return -1;
assert(actual == count);
}
mOffset += actual;
return actual;
}
/*
* Seek to a new position.
*/
off_t _FileAsset::seek(off_t offset, int whence)
{
off_t newPosn;
long actualOffset;
// compute new position within chunk
newPosn = handleSeek(offset, whence, mOffset, mLength);
if (newPosn == (off_t) -1)
return newPosn;
actualOffset = (long) (mStart + newPosn);
if (mFp != NULL) {
if (fseek(mFp, (long) actualOffset, SEEK_SET) != 0)
return (off_t) -1;
}
mOffset = actualOffset - mStart;
return mOffset;
}
/*
* Close the asset.
*/
void _FileAsset::close(void)
{
if (mMap != NULL) {
mMap->release();
mMap = NULL;
}
if (mBuf != NULL) {
delete[] mBuf;
mBuf = NULL;
}
if (mFileName != NULL) {
free(mFileName);
mFileName = NULL;
}
if (mFp != NULL) {
// can only be NULL when called from destructor
// (otherwise we would never return this object)
fclose(mFp);
mFp = NULL;
}
}
/*
* Return a read-only pointer to a buffer.
*
* We can either read the whole thing in or map the relevant piece of
* the source file. Ideally a map would be established at a higher
* level and we'd be using a different object, but we didn't, so we
* deal with it here.
*/
const void* _FileAsset::getBuffer(bool wordAligned)
{
/* subsequent requests just use what we did previously */
if (mBuf != NULL)
return mBuf;
if (mMap != NULL) {
if (!wordAligned) {
return mMap->getDataPtr();
}
return ensureAlignment(mMap);
}
assert(mFp != NULL);
if (mLength < kReadVsMapThreshold) {
unsigned char* buf;
long allocLen;
/* zero-length files are allowed; not sure about zero-len allocs */
/* (works fine with gcc + x86linux) */
allocLen = mLength;
if (mLength == 0)
allocLen = 1;
buf = new unsigned char[allocLen];
if (buf == NULL) {
LOGE("alloc of %ld bytes failed\n", (long) allocLen);
return NULL;
}
LOGV("Asset %p allocating buffer size %d (smaller than threshold)", this, (int)allocLen);
if (mLength > 0) {
long oldPosn = ftell(mFp);
fseek(mFp, mStart, SEEK_SET);
if (fread(buf, 1, mLength, mFp) != (size_t) mLength) {
LOGE("failed reading %ld bytes\n", (long) mLength);
delete[] buf;
return NULL;
}
fseek(mFp, oldPosn, SEEK_SET);
}
LOGV(" getBuffer: loaded into buffer\n");
mBuf = buf;
return mBuf;
} else {
FileMap* map;
map = new FileMap;
if (!map->create(NULL, fileno(mFp), mStart, mLength, true)) {
map->release();
return NULL;
}
LOGV(" getBuffer: mapped\n");
mMap = map;
if (!wordAligned) {
return mMap->getDataPtr();
}
return ensureAlignment(mMap);
}
}
int _FileAsset::openFileDescriptor(off_t* outStart, off_t* outLength) const
{
if (mMap != NULL) {
const char* fname = mMap->getFileName();
if (fname == NULL) {
fname = mFileName;
}
if (fname == NULL) {
return -1;
}
*outStart = mMap->getDataOffset();
*outLength = mMap->getDataLength();
return open(fname, O_RDONLY | O_BINARY);
}
if (mFileName == NULL) {
return -1;
}
*outStart = mStart;
*outLength = mLength;
return open(mFileName, O_RDONLY | O_BINARY);
}
const void* _FileAsset::ensureAlignment(FileMap* map)
{
void* data = map->getDataPtr();
if ((((size_t)data)&0x3) == 0) {
// We can return this directly if it is aligned on a word
// boundary.
LOGV("Returning aligned FileAsset %p (%s).", this,
getAssetSource());
return data;
}
// If not aligned on a word boundary, then we need to copy it into
// our own buffer.
LOGV("Copying FileAsset %p (%s) to buffer size %d to make it aligned.", this,
getAssetSource(), (int)mLength);
unsigned char* buf = new unsigned char[mLength];
if (buf == NULL) {
LOGE("alloc of %ld bytes failed\n", (long) mLength);
return NULL;
}
memcpy(buf, data, mLength);
mBuf = buf;
return buf;
}
/*
* ===========================================================================
* _CompressedAsset
* ===========================================================================
*/
/*
* Constructor.
*/
_CompressedAsset::_CompressedAsset(void)
: mStart(0), mCompressedLen(0), mUncompressedLen(0), mOffset(0),
mMap(NULL), mFd(-1), mZipInflater(NULL), mBuf(NULL)
{
}
/*
* Destructor. Release resources.
*/
_CompressedAsset::~_CompressedAsset(void)
{
close();
}
/*
* Open a chunk of compressed data inside a file.
*
* This currently just sets up some values and returns. On the first
* read, we expand the entire file into a buffer and return data from it.
*/
status_t _CompressedAsset::openChunk(int fd, off_t offset,
int compressionMethod, size_t uncompressedLen, size_t compressedLen)
{
assert(mFd < 0); // no re-open
assert(mMap == NULL);
assert(fd >= 0);
assert(offset >= 0);
assert(compressedLen > 0);
if (compressionMethod != ZipFileRO::kCompressDeflated) {
assert(false);
return UNKNOWN_ERROR;
}
mStart = offset;
mCompressedLen = compressedLen;
mUncompressedLen = uncompressedLen;
assert(mOffset == 0);
mFd = fd;
assert(mBuf == NULL);
if (uncompressedLen > StreamingZipInflater::OUTPUT_CHUNK_SIZE) {
mZipInflater = new StreamingZipInflater(mFd, offset, uncompressedLen, compressedLen);
}
return NO_ERROR;
}
/*
* Open a chunk of compressed data in a mapped region.
*
* Nothing is expanded until the first read call.
*/
status_t _CompressedAsset::openChunk(FileMap* dataMap, int compressionMethod,
size_t uncompressedLen)
{
assert(mFd < 0); // no re-open
assert(mMap == NULL);
assert(dataMap != NULL);
if (compressionMethod != ZipFileRO::kCompressDeflated) {
assert(false);
return UNKNOWN_ERROR;
}
mMap = dataMap;
mStart = -1; // not used
mCompressedLen = dataMap->getDataLength();
mUncompressedLen = uncompressedLen;
assert(mOffset == 0);
if (uncompressedLen > StreamingZipInflater::OUTPUT_CHUNK_SIZE) {
mZipInflater = new StreamingZipInflater(dataMap, uncompressedLen);
}
return NO_ERROR;
}
/*
* Read data from a chunk of compressed data.
*
* [For now, that's just copying data out of a buffer.]
*/
ssize_t _CompressedAsset::read(void* buf, size_t count)
{
size_t maxLen;
size_t actual;
assert(mOffset >= 0 && mOffset <= mUncompressedLen);
/* If we're relying on a streaming inflater, go through that */
if (mZipInflater) {
actual = mZipInflater->read(buf, count);
} else {
if (mBuf == NULL) {
if (getBuffer(false) == NULL)
return -1;
}
assert(mBuf != NULL);
/* adjust count if we're near EOF */
maxLen = mUncompressedLen - mOffset;
if (count > maxLen)
count = maxLen;
if (!count)
return 0;
/* copy from buffer */
//printf("comp buf read\n");
memcpy(buf, (char*)mBuf + mOffset, count);
actual = count;
}
mOffset += actual;
return actual;
}
/*
* Handle a seek request.
*
* If we're working in a streaming mode, this is going to be fairly
* expensive, because it requires plowing through a bunch of compressed
* data.
*/
off_t _CompressedAsset::seek(off_t offset, int whence)
{
off_t newPosn;
// compute new position within chunk
newPosn = handleSeek(offset, whence, mOffset, mUncompressedLen);
if (newPosn == (off_t) -1)
return newPosn;
if (mZipInflater) {
mZipInflater->seekAbsolute(newPosn);
}
mOffset = newPosn;
return mOffset;
}
/*
* Close the asset.
*/
void _CompressedAsset::close(void)
{
if (mMap != NULL) {
mMap->release();
mMap = NULL;
}
delete[] mBuf;
mBuf = NULL;
delete mZipInflater;
mZipInflater = NULL;
if (mFd > 0) {
::close(mFd);
mFd = -1;
}
}
/*
* Get a pointer to a read-only buffer of data.
*
* The first time this is called, we expand the compressed data into a
* buffer.
*/
const void* _CompressedAsset::getBuffer(bool wordAligned)
{
unsigned char* buf = NULL;
if (mBuf != NULL)
return mBuf;
/*
* Allocate a buffer and read the file into it.
*/
buf = new unsigned char[mUncompressedLen];
if (buf == NULL) {
LOGW("alloc %ld bytes failed\n", (long) mUncompressedLen);
goto bail;
}
if (mMap != NULL) {
if (!ZipFileRO::inflateBuffer(buf, mMap->getDataPtr(),
mUncompressedLen, mCompressedLen))
goto bail;
} else {
assert(mFd >= 0);
/*
* Seek to the start of the compressed data.
*/
if (lseek(mFd, mStart, SEEK_SET) != mStart)
goto bail;
/*
* Expand the data into it.
*/
if (!ZipUtils::inflateToBuffer(mFd, buf, mUncompressedLen,
mCompressedLen))
goto bail;
}
/*
* Success - now that we have the full asset in RAM we
* no longer need the streaming inflater
*/
delete mZipInflater;
mZipInflater = NULL;
mBuf = buf;
buf = NULL;
bail:
delete[] buf;
return mBuf;
}