CachedLocalSdkStorage.kt
/*
* Copyright 2022 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.
*/
package androidx.privacysandbox.sdkruntime.client.loader.storage
import android.content.Context
import android.os.Build
import android.os.Build.VERSION_CODES.JELLY_BEAN_MR2
import android.os.Environment
import android.os.StatFs
import android.util.Log
import androidx.annotation.DoNotInline
import androidx.annotation.RequiresApi
import androidx.privacysandbox.sdkruntime.client.config.LocalSdkConfig
import java.io.File
/**
* Caching implementation of [LocalSdkStorage].
*
* Extract SDK DEX files into folder provided by [LocalSdkFolderProvider].
* Not extracting new files if available space lower than lowSpaceThreshold.
* Return result only if all files successfully extracted.
*/
internal class CachedLocalSdkStorage private constructor(
private val context: Context,
private val rootFolderProvider: LocalSdkFolderProvider,
private val lowSpaceThreshold: Long
) : LocalSdkStorage {
/**
* Return SDK DEX files from folder provided by [LocalSdkFolderProvider].
* Extract missing files from assets if available space bigger than lowSpaceThreshold.
*
* @param sdkConfig sdk config
* @return [LocalSdkDexFiles] if all SDK DEX files available in SDK folder
* or null if something missing and couldn't be extracted because of
* available space lower than lowSpaceThreshold
*/
override fun dexFilesFor(sdkConfig: LocalSdkConfig): LocalSdkDexFiles? {
val disableExtracting = availableBytes() < lowSpaceThreshold
val targetFolder = rootFolderProvider.dexFolderFor(sdkConfig)
try {
val files = buildList {
for (index in sdkConfig.dexPaths.indices) {
val assetName = sdkConfig.dexPaths[index]
val outputFileName = "$index.dex"
val outputDexFile = File(targetFolder, outputFileName)
if (!outputDexFile.exists()) {
if (disableExtracting) {
Log.i(LOG_TAG, "Can't extract $assetName because of low space")
return null
}
extractAssetToFile(assetName, outputDexFile)
}
add(outputDexFile)
}
}
return LocalSdkDexFiles(files)
} catch (ex: Exception) {
Log.e(
LOG_TAG,
"Failed to extract ${sdkConfig.packageName}, deleting $targetFolder.",
ex
)
if (!targetFolder.deleteRecursively()) {
Log.e(
LOG_TAG,
"Failed to delete $targetFolder during cleanup.",
ex
)
}
throw ex
}
}
private fun extractAssetToFile(
assetName: String,
outputFile: File,
) {
outputFile.createNewFile()
context.assets.open(assetName).use { fromStream ->
outputFile.outputStream().use { toStream ->
fromStream.copyTo(toStream)
}
}
outputFile.setReadOnly()
}
private fun availableBytes(): Long {
val dataDirectory = Environment.getDataDirectory()
val statFs = StatFs(dataDirectory.path)
if (Build.VERSION.SDK_INT >= JELLY_BEAN_MR2) {
return Api18Impl.availableBytes(statFs)
}
@Suppress("DEPRECATION")
val blockSize = statFs.blockSize.toLong()
@Suppress("DEPRECATION")
val availableBlocks = statFs.availableBlocks.toLong()
return availableBlocks * blockSize
}
@RequiresApi(JELLY_BEAN_MR2)
private object Api18Impl {
@DoNotInline
fun availableBytes(statFs: StatFs) = statFs.availableBytes
}
companion object {
const val LOG_TAG = "CachedLocalSdkStorage"
/**
* Create CachedLocalSdkStorage.
*
* @param context Application context
* @param lowSpaceThreshold Minimal available space in bytes required to proceed with
* extracting new SDK Dex files.
*/
fun create(
context: Context,
lowSpaceThreshold: Long
): CachedLocalSdkStorage {
val localSdkFolderProvider = LocalSdkFolderProvider.create(context)
return CachedLocalSdkStorage(context, localSdkFolderProvider, lowSpaceThreshold)
}
}
}