base/android/apk_assets.cc

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include <jni.h>
   6
   7 #include "base/android/apk_assets.h"
   8
   9 #include "base/android/jni_array.h"
  10 #include "base/android/jni_string.h"
  11 #include "base/android/scoped_java_ref.h"
  12 #include "jni/ApkAssets_jni.h"
  13
  14 namespace base {
  15 namespace android {
  16
  17 bool RegisterApkAssets(JNIEnv* env) {
  18   return RegisterNativesImpl(env);
  19 }
  20
  21 int OpenApkAsset(const std::string& file_path,
  22                  base::MemoryMappedFile::Region* region) {
  23   // The AAssetManager API of the NDK is does not expose a method for accessing
  24   // raw resources :(.
  25   JNIEnv* env = base::android::AttachCurrentThread();
  26   ScopedJavaLocalRef<jlongArray> jarr = Java_ApkAssets_open(
  27       env,
  28       base::android::GetApplicationContext(),
  29       base::android::ConvertUTF8ToJavaString(env, file_path).obj());
  30   std::vector<jlong> results;
  31   base::android::JavaLongArrayToLongVector(env, jarr.obj(), &results);
  32   CHECK_EQ(3U, results.size());
  33   int fd = static_cast<int>(results[0]);
  34   region->offset = results[1];
  35   region->size = results[2];
  36   return fd;
  37 }
  38
  39 bool RegisterApkAssetWithGlobalDescriptors(base::GlobalDescriptors::Key key,
  40                                            const std::string& file_path) {
  41   base::MemoryMappedFile::Region region =
  42       base::MemoryMappedFile::Region::kWholeFile;
  43   int asset_fd = OpenApkAsset(file_path, &region);
  44   if (asset_fd != -1) {
  45     base::GlobalDescriptors::GetInstance()->Set(key, asset_fd, region);
  46   }
  47   return asset_fd != -1;
  48 }
  49
  50 }  // namespace android
  51 }  // namespace base