| // Copyright 2014 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| package org.chromium.base; |
| |
| import android.content.res.AssetFileDescriptor; |
| import android.content.res.AssetManager; |
| import android.util.Log; |
| |
| import org.chromium.base.annotations.CalledByNative; |
| import org.chromium.base.annotations.JNINamespace; |
| |
| import java.io.IOException; |
| |
| /** |
| * A utility class to retrieve references to uncompressed assets insides the apk. A reference is |
| * defined as tuple (file descriptor, offset, size) enabling direct mapping without deflation. |
| * This can be used even within the renderer process, since it just dup's the apk's fd. |
| */ |
| @JNINamespace("base::android") |
| public class ApkAssets { |
| private static final String LOGTAG = "ApkAssets"; |
| |
| @CalledByNative |
| public static long[] open(String fileName) { |
| AssetFileDescriptor afd = null; |
| try { |
| AssetManager manager = ContextUtils.getApplicationContext().getAssets(); |
| afd = manager.openNonAssetFd(fileName); |
| return new long[] {afd.getParcelFileDescriptor().detachFd(), afd.getStartOffset(), |
| afd.getLength()}; |
| } catch (IOException e) { |
| // As a general rule there's no point logging here because the caller should handle |
| // receiving an fd of -1 sensibly, and the log message is either mirrored later, or |
| // unwanted (in the case where a missing file is expected), or wanted but will be |
| // ignored, as most non-fatal logs are. |
| // It makes sense to log here when the file exists, but is unable to be opened as an fd |
| // because (for example) it is unexpectedly compressed in an apk. In that case, the log |
| // message might save someone some time working out what has gone wrong. |
| // For that reason, we only suppress the message when the exception message doesn't look |
| // informative (Android framework passes the filename as the message on actual file not |
| // found, and the empty string also wouldn't give any useful information for debugging). |
| if (!e.getMessage().equals("") && !e.getMessage().equals(fileName)) { |
| Log.e(LOGTAG, "Error while loading asset " + fileName + ": " + e); |
| } |
| return new long[] {-1, -1, -1}; |
| } finally { |
| try { |
| if (afd != null) { |
| afd.close(); |
| } |
| } catch (IOException e2) { |
| Log.e(LOGTAG, "Unable to close AssetFileDescriptor", e2); |
| } |
| } |
| } |
| } |