865 lines
20 KiB
C++
865 lines
20 KiB
C++
/*
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* Copyright (C) 2006 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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//
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// Provide access to a read-only asset.
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//
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#define LOG_TAG "asset"
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//#define NDEBUG 0
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#include <utils/Asset.h>
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#include <utils/Atomic.h>
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#include <utils/FileMap.h>
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#include <utils/ZipUtils.h>
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#include <utils/ZipFileRO.h>
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#include <utils/Log.h>
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#include <utils/threads.h>
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#include <string.h>
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#include <memory.h>
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#include <fcntl.h>
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#include <errno.h>
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#include <assert.h>
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using namespace android;
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#ifndef O_BINARY
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# define O_BINARY 0
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#endif
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static Mutex gAssetLock;
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static int32_t gCount = 0;
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static Asset* gHead = NULL;
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static Asset* gTail = NULL;
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int32_t Asset::getGlobalCount()
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{
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AutoMutex _l(gAssetLock);
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return gCount;
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}
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String8 Asset::getAssetAllocations()
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{
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AutoMutex _l(gAssetLock);
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String8 res;
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Asset* cur = gHead;
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while (cur != NULL) {
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if (cur->isAllocated()) {
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res.append(" ");
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res.append(cur->getAssetSource());
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off_t size = (cur->getLength()+512)/1024;
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char buf[64];
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sprintf(buf, ": %dK\n", (int)size);
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res.append(buf);
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}
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cur = cur->mNext;
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}
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return res;
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}
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Asset::Asset(void)
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: mAccessMode(ACCESS_UNKNOWN)
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{
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AutoMutex _l(gAssetLock);
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gCount++;
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mNext = mPrev = NULL;
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if (gTail == NULL) {
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gHead = gTail = this;
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} else {
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mPrev = gTail;
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gTail->mNext = this;
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gTail = this;
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}
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//LOGI("Creating Asset %p #%d\n", this, gCount);
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}
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Asset::~Asset(void)
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{
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AutoMutex _l(gAssetLock);
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gCount--;
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if (gHead == this) {
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gHead = mNext;
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}
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if (gTail == this) {
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gTail = mPrev;
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}
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if (mNext != NULL) {
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mNext->mPrev = mPrev;
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}
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if (mPrev != NULL) {
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mPrev->mNext = mNext;
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}
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mNext = mPrev = NULL;
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//LOGI("Destroying Asset in %p #%d\n", this, gCount);
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}
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/*
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* Create a new Asset from a file on disk. There is a fair chance that
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* the file doesn't actually exist.
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*
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* We can use "mode" to decide how we want to go about it.
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*/
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/*static*/ Asset* Asset::createFromFile(const char* fileName, AccessMode mode)
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{
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_FileAsset* pAsset;
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status_t result;
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off_t length;
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int fd;
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fd = open(fileName, O_RDONLY | O_BINARY);
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if (fd < 0)
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return NULL;
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/*
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* Under Linux, the lseek fails if we actually opened a directory. To
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* be correct we should test the file type explicitly, but since we
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* always open things read-only it doesn't really matter, so there's
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* no value in incurring the extra overhead of an fstat() call.
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*/
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length = lseek(fd, 0, SEEK_END);
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if (length < 0) {
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::close(fd);
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return NULL;
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}
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(void) lseek(fd, 0, SEEK_SET);
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pAsset = new _FileAsset;
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result = pAsset->openChunk(fileName, fd, 0, length);
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if (result != NO_ERROR) {
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delete pAsset;
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return NULL;
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}
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pAsset->mAccessMode = mode;
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return pAsset;
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}
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/*
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* Create a new Asset from a compressed file on disk. There is a fair chance
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* that the file doesn't actually exist.
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*
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* We currently support gzip files. We might want to handle .bz2 someday.
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*/
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/*static*/ Asset* Asset::createFromCompressedFile(const char* fileName,
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AccessMode mode)
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{
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_CompressedAsset* pAsset;
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status_t result;
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off_t fileLen;
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bool scanResult;
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long offset;
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int method;
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long uncompressedLen, compressedLen;
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int fd;
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fd = open(fileName, O_RDONLY | O_BINARY);
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if (fd < 0)
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return NULL;
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fileLen = lseek(fd, 0, SEEK_END);
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if (fileLen < 0) {
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::close(fd);
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return NULL;
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}
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(void) lseek(fd, 0, SEEK_SET);
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/* want buffered I/O for the file scan; must dup so fclose() is safe */
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FILE* fp = fdopen(dup(fd), "rb");
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if (fp == NULL) {
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::close(fd);
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return NULL;
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}
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unsigned long crc32;
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scanResult = ZipUtils::examineGzip(fp, &method, &uncompressedLen,
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&compressedLen, &crc32);
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offset = ftell(fp);
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fclose(fp);
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if (!scanResult) {
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LOGD("File '%s' is not in gzip format\n", fileName);
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::close(fd);
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return NULL;
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}
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pAsset = new _CompressedAsset;
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result = pAsset->openChunk(fd, offset, method, uncompressedLen,
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compressedLen);
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if (result != NO_ERROR) {
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delete pAsset;
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return NULL;
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}
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pAsset->mAccessMode = mode;
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return pAsset;
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}
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#if 0
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/*
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* Create a new Asset from part of an open file.
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*/
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/*static*/ Asset* Asset::createFromFileSegment(int fd, off_t offset,
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size_t length, AccessMode mode)
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{
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_FileAsset* pAsset;
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status_t result;
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pAsset = new _FileAsset;
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result = pAsset->openChunk(NULL, fd, offset, length);
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if (result != NO_ERROR)
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return NULL;
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pAsset->mAccessMode = mode;
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return pAsset;
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}
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/*
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* Create a new Asset from compressed data in an open file.
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*/
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/*static*/ Asset* Asset::createFromCompressedData(int fd, off_t offset,
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int compressionMethod, size_t uncompressedLen, size_t compressedLen,
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AccessMode mode)
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{
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_CompressedAsset* pAsset;
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status_t result;
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pAsset = new _CompressedAsset;
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result = pAsset->openChunk(fd, offset, compressionMethod,
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uncompressedLen, compressedLen);
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if (result != NO_ERROR)
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return NULL;
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pAsset->mAccessMode = mode;
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return pAsset;
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}
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#endif
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/*
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* Create a new Asset from a memory mapping.
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*/
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/*static*/ Asset* Asset::createFromUncompressedMap(FileMap* dataMap,
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AccessMode mode)
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{
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_FileAsset* pAsset;
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status_t result;
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pAsset = new _FileAsset;
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result = pAsset->openChunk(dataMap);
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if (result != NO_ERROR)
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return NULL;
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pAsset->mAccessMode = mode;
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return pAsset;
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}
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/*
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* Create a new Asset from compressed data in a memory mapping.
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*/
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/*static*/ Asset* Asset::createFromCompressedMap(FileMap* dataMap,
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int method, size_t uncompressedLen, AccessMode mode)
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{
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_CompressedAsset* pAsset;
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status_t result;
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pAsset = new _CompressedAsset;
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result = pAsset->openChunk(dataMap, method, uncompressedLen);
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if (result != NO_ERROR)
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return NULL;
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pAsset->mAccessMode = mode;
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return pAsset;
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}
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/*
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* Do generic seek() housekeeping. Pass in the offset/whence values from
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* the seek request, along with the current chunk offset and the chunk
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* length.
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*
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* Returns the new chunk offset, or -1 if the seek is illegal.
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*/
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off_t Asset::handleSeek(off_t offset, int whence, off_t curPosn, off_t maxPosn)
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{
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off_t newOffset;
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switch (whence) {
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case SEEK_SET:
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newOffset = offset;
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break;
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case SEEK_CUR:
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newOffset = curPosn + offset;
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break;
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case SEEK_END:
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newOffset = maxPosn + offset;
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break;
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default:
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LOGW("unexpected whence %d\n", whence);
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// this was happening due to an off_t size mismatch
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assert(false);
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return (off_t) -1;
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}
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if (newOffset < 0 || newOffset > maxPosn) {
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LOGW("seek out of range: want %ld, end=%ld\n",
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(long) newOffset, (long) maxPosn);
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return (off_t) -1;
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}
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return newOffset;
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}
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/*
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* ===========================================================================
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* _FileAsset
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* ===========================================================================
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*/
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/*
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* Constructor.
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*/
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_FileAsset::_FileAsset(void)
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: mStart(0), mLength(0), mOffset(0), mFp(NULL), mFileName(NULL), mMap(NULL), mBuf(NULL)
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{
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}
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/*
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* Destructor. Release resources.
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*/
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_FileAsset::~_FileAsset(void)
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{
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close();
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}
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/*
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* Operate on a chunk of an uncompressed file.
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*
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* Zero-length chunks are allowed.
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*/
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status_t _FileAsset::openChunk(const char* fileName, int fd, off_t offset, size_t length)
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{
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assert(mFp == NULL); // no reopen
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assert(mMap == NULL);
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assert(fd >= 0);
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assert(offset >= 0);
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/*
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* Seek to end to get file length.
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*/
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off_t fileLength;
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fileLength = lseek(fd, 0, SEEK_END);
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if (fileLength == (off_t) -1) {
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// probably a bad file descriptor
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LOGD("failed lseek (errno=%d)\n", errno);
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return UNKNOWN_ERROR;
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}
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if ((off_t) (offset + length) > fileLength) {
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LOGD("start (%ld) + len (%ld) > end (%ld)\n",
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(long) offset, (long) length, (long) fileLength);
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return BAD_INDEX;
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}
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/* after fdopen, the fd will be closed on fclose() */
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mFp = fdopen(fd, "rb");
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if (mFp == NULL)
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return UNKNOWN_ERROR;
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mStart = offset;
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mLength = length;
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assert(mOffset == 0);
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/* seek the FILE* to the start of chunk */
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if (fseek(mFp, mStart, SEEK_SET) != 0) {
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assert(false);
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}
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mFileName = fileName != NULL ? strdup(fileName) : NULL;
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return NO_ERROR;
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}
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/*
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* Create the chunk from the map.
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*/
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status_t _FileAsset::openChunk(FileMap* dataMap)
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{
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assert(mFp == NULL); // no reopen
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assert(mMap == NULL);
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assert(dataMap != NULL);
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mMap = dataMap;
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mStart = -1; // not used
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mLength = dataMap->getDataLength();
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assert(mOffset == 0);
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return NO_ERROR;
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}
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/*
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* Read a chunk of data.
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*/
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ssize_t _FileAsset::read(void* buf, size_t count)
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{
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size_t maxLen;
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size_t actual;
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assert(mOffset >= 0 && mOffset <= mLength);
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if (getAccessMode() == ACCESS_BUFFER) {
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/*
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* On first access, read or map the entire file. The caller has
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* requested buffer access, either because they're going to be
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* using the buffer or because what they're doing has appropriate
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* performance needs and access patterns.
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*/
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if (mBuf == NULL)
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getBuffer(false);
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}
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/* adjust count if we're near EOF */
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maxLen = mLength - mOffset;
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if (count > maxLen)
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count = maxLen;
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if (!count)
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return 0;
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if (mMap != NULL) {
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/* copy from mapped area */
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//printf("map read\n");
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memcpy(buf, (char*)mMap->getDataPtr() + mOffset, count);
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actual = count;
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} else if (mBuf != NULL) {
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/* copy from buffer */
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//printf("buf read\n");
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memcpy(buf, (char*)mBuf + mOffset, count);
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actual = count;
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} else {
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/* read from the file */
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//printf("file read\n");
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if (ftell(mFp) != mStart + mOffset) {
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LOGE("Hosed: %ld != %ld+%ld\n",
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ftell(mFp), (long) mStart, (long) mOffset);
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assert(false);
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}
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/*
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* This returns 0 on error or eof. We need to use ferror() or feof()
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* to tell the difference, but we don't currently have those on the
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* device. However, we know how much data is *supposed* to be in the
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* file, so if we don't read the full amount we know something is
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* hosed.
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*/
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actual = fread(buf, 1, count, mFp);
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if (actual == 0) // something failed -- I/O error?
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return -1;
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assert(actual == count);
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}
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mOffset += actual;
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return actual;
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}
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/*
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* Seek to a new position.
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*/
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off_t _FileAsset::seek(off_t offset, int whence)
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{
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off_t newPosn;
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long actualOffset;
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// compute new position within chunk
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newPosn = handleSeek(offset, whence, mOffset, mLength);
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if (newPosn == (off_t) -1)
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return newPosn;
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actualOffset = (long) (mStart + newPosn);
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if (mFp != NULL) {
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if (fseek(mFp, (long) actualOffset, SEEK_SET) != 0)
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return (off_t) -1;
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}
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mOffset = actualOffset - mStart;
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return mOffset;
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}
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/*
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* Close the asset.
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*/
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void _FileAsset::close(void)
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{
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if (mMap != NULL) {
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mMap->release();
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mMap = NULL;
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}
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if (mBuf != NULL) {
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delete[] mBuf;
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mBuf = NULL;
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}
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if (mFileName != NULL) {
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free(mFileName);
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mFileName = NULL;
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}
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if (mFp != NULL) {
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// can only be NULL when called from destructor
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// (otherwise we would never return this object)
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fclose(mFp);
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mFp = NULL;
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}
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}
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|
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/*
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* Return a read-only pointer to a buffer.
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*
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* We can either read the whole thing in or map the relevant piece of
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* the source file. Ideally a map would be established at a higher
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* level and we'd be using a different object, but we didn't, so we
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* deal with it here.
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*/
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const void* _FileAsset::getBuffer(bool wordAligned)
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{
|
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/* subsequent requests just use what we did previously */
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if (mBuf != NULL)
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return mBuf;
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if (mMap != NULL) {
|
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if (!wordAligned) {
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return mMap->getDataPtr();
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}
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return ensureAlignment(mMap);
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}
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|
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assert(mFp != NULL);
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|
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if (mLength < kReadVsMapThreshold) {
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unsigned char* buf;
|
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long allocLen;
|
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|
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/* zero-length files are allowed; not sure about zero-len allocs */
|
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/* (works fine with gcc + x86linux) */
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allocLen = mLength;
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if (mLength == 0)
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allocLen = 1;
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buf = new unsigned char[allocLen];
|
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if (buf == NULL) {
|
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LOGE("alloc of %ld bytes failed\n", (long) allocLen);
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return NULL;
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}
|
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|
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LOGV("Asset %p allocating buffer size %d (smaller than threshold)", this, (int)allocLen);
|
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if (mLength > 0) {
|
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long oldPosn = ftell(mFp);
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fseek(mFp, mStart, SEEK_SET);
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if (fread(buf, 1, mLength, mFp) != (size_t) mLength) {
|
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LOGE("failed reading %ld bytes\n", (long) mLength);
|
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delete[] buf;
|
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return NULL;
|
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}
|
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fseek(mFp, oldPosn, SEEK_SET);
|
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}
|
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|
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LOGV(" getBuffer: loaded into buffer\n");
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|
|
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), 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);
|
|
|
|
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);
|
|
|
|
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);
|
|
|
|
// TODO: if mAccessMode == ACCESS_STREAMING, use zlib more cleverly
|
|
|
|
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;
|
|
|
|
mOffset = newPosn;
|
|
return mOffset;
|
|
}
|
|
|
|
/*
|
|
* Close the asset.
|
|
*/
|
|
void _CompressedAsset::close(void)
|
|
{
|
|
if (mMap != NULL) {
|
|
mMap->release();
|
|
mMap = NULL;
|
|
}
|
|
if (mBuf != NULL) {
|
|
delete[] mBuf;
|
|
mBuf = 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;
|
|
|
|
if (mUncompressedLen > UNCOMPRESS_DATA_MAX) {
|
|
LOGD("Data exceeds UNCOMPRESS_DATA_MAX (%ld vs %d)\n",
|
|
(long) mUncompressedLen, UNCOMPRESS_DATA_MAX);
|
|
goto bail;
|
|
}
|
|
|
|
/*
|
|
* 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! */
|
|
mBuf = buf;
|
|
buf = NULL;
|
|
|
|
bail:
|
|
delete[] buf;
|
|
return mBuf;
|
|
}
|
|
|