M7350/base/native/android/asset_manager.cpp

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2024-09-09 08:52:07 +00:00
/*
* Copyright (C) 2010 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.
*/
#define LOG_TAG "NAsset"
#include <utils/Log.h>
#include <android/asset_manager_jni.h>
#include <utils/AssetManager.h>
#include <utils/AssetDir.h>
#include <utils/Asset.h>
#include <utils/threads.h>
#include "jni.h"
#include "JNIHelp.h"
using namespace android;
// -------------------- Backing implementation of the public API --------------------
// AAssetManager is actually a secret typedef for an empty base class of AssetManager,
// but AAssetDir and AAsset are actual wrappers for isolation.
// -----
struct AAssetDir {
AssetDir* mAssetDir;
size_t mCurFileIndex;
String8 mCachedFileName;
AAssetDir(AssetDir* dir) : mAssetDir(dir), mCurFileIndex(0) { }
~AAssetDir() { delete mAssetDir; }
};
// -----
struct AAsset {
Asset* mAsset;
AAsset(Asset* asset) : mAsset(asset) { }
~AAsset() { delete mAsset; }
};
// -------------------- Public native C API --------------------
/**
* Supporting information
*/
static struct assetmanager_offsets_t
{
jfieldID mObject;
} gAssetManagerOffsets;
static volatile bool gJNIConfigured = false;
static Mutex gMutex;
/**
* Asset Manager functionality
*/
AAssetManager* AAssetManager_fromJava(JNIEnv* env, jobject assetManager)
{
{
Mutex::Autolock _l(gMutex);
if (gJNIConfigured == false) {
jclass amClass = env->FindClass("android/content/res/AssetManager");
gAssetManagerOffsets.mObject = env->GetFieldID(amClass, "mObject", "I");
gJNIConfigured = true;
}
}
return (AAssetManager*) env->GetIntField(assetManager, gAssetManagerOffsets.mObject);
}
AAsset* AAssetManager_open(AAssetManager* amgr, const char* filename, int mode)
{
Asset::AccessMode amMode;
switch (mode) {
case AASSET_MODE_UNKNOWN:
amMode = Asset::ACCESS_UNKNOWN;
break;
case AASSET_MODE_RANDOM:
amMode = Asset::ACCESS_RANDOM;
break;
case AASSET_MODE_STREAMING:
amMode = Asset::ACCESS_STREAMING;
break;
case AASSET_MODE_BUFFER:
amMode = Asset::ACCESS_BUFFER;
break;
default:
return NULL;
}
AssetManager* mgr = static_cast<AssetManager*>(amgr);
Asset* asset = mgr->open(filename, amMode);
if (asset == NULL) {
return NULL;
}
return new AAsset(asset);
}
AAssetDir* AAssetManager_openDir(AAssetManager* amgr, const char* dirName)
{
AssetManager* mgr = static_cast<AssetManager*>(amgr);
return new AAssetDir(mgr->openDir(dirName));
}
/**
* AssetDir functionality
*/
const char* AAssetDir_getNextFileName(AAssetDir* assetDir)
{
const char* returnName = NULL;
size_t index = assetDir->mCurFileIndex;
const size_t max = assetDir->mAssetDir->getFileCount();
// Find the next regular file; explicitly don't report directories even if the
// underlying implementation changes to report them. At that point we can add
// a more general iterator to this native interface set if appropriate.
while ((index < max) && (assetDir->mAssetDir->getFileType(index) != kFileTypeRegular)) {
index++;
}
// still in bounds? then the one at 'index' is the next to be reported; generate
// the string to return and advance the iterator for next time.
if (index < max) {
assetDir->mCachedFileName = assetDir->mAssetDir->getFileName(index);
returnName = assetDir->mCachedFileName.string();
index++;
}
assetDir->mCurFileIndex = index;
return returnName;
}
void AAssetDir_rewind(AAssetDir* assetDir)
{
assetDir->mCurFileIndex = 0;
}
const char* AAssetDir_getFileName(AAssetDir* assetDir, int index)
{
assetDir->mCachedFileName = assetDir->mAssetDir->getFileName(index);
return assetDir->mCachedFileName.string();
}
void AAssetDir_close(AAssetDir* assetDir)
{
delete assetDir;
}
/**
* Asset functionality
*/
int AAsset_read(AAsset* asset, void* buf, size_t count)
{
return asset->mAsset->read(buf, (size_t)count);
}
off_t AAsset_seek(AAsset* asset, off_t offset, int whence)
{
return asset->mAsset->seek(offset, whence);
}
void AAsset_close(AAsset* asset)
{
asset->mAsset->close();
delete asset;
}
const void* AAsset_getBuffer(AAsset* asset)
{
return asset->mAsset->getBuffer(false);
}
off_t AAsset_getLength(AAsset* asset)
{
return asset->mAsset->getLength();
}
off_t AAsset_getRemainingLength(AAsset* asset)
{
return asset->mAsset->getRemainingLength();
}
int AAsset_openFileDescriptor(AAsset* asset, off_t* outStart, off_t* outLength)
{
return asset->mAsset->openFileDescriptor(outStart, outLength);
}
int AAsset_isAllocated(AAsset* asset)
{
return asset->mAsset->isAllocated() ? 1 : 0;
}