android_frameworks_base/libs/androidfw/ResourceUtils.cpp

/*
 * Copyright (C) 2017 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.
 */

#include "androidfw/ResourceUtils.h"

namespace android {

bool ExtractResourceName(const StringPiece& str, StringPiece* out_package, StringPiece* out_type,
                         StringPiece* out_entry) {
  *out_package = "";
  *out_type = "";
  bool has_package_separator = false;
  bool has_type_separator = false;
  const char* start = str.data();
  const char* end = start + str.size();
  if (start[0] == '@') {
      start++;
  }
  const char* current = start;
  while (current != end) {
    if (out_type->size() == 0 && *current == '/') {
      has_type_separator = true;
      out_type->assign(start, current - start);
      start = current + 1;
    } else if (out_package->size() == 0 && *current == ':') {
      has_package_separator = true;
      out_package->assign(start, current - start);
      start = current + 1;
    }
    current++;
  }
  out_entry->assign(start, end - start);

  return !(has_package_separator && out_package->empty()) &&
         !(has_type_separator && out_type->empty());
}

bool ToResourceName(const StringPoolRef& type_string_ref,
                    const StringPoolRef& entry_string_ref,
                    const StringPiece& package_name,
                    AssetManager2::ResourceName* out_name) {
  out_name->package = package_name.data();
  out_name->package_len = package_name.size();

  out_name->type = type_string_ref.string8(&out_name->type_len);
  out_name->type16 = nullptr;
  if (out_name->type == nullptr) {
    out_name->type16 = type_string_ref.string16(&out_name->type_len);
    if (out_name->type16 == nullptr) {
      return false;
    }
  }

  out_name->entry = entry_string_ref.string8(&out_name->entry_len);
  out_name->entry16 = nullptr;
  if (out_name->entry == nullptr) {
    out_name->entry16 = entry_string_ref.string16(&out_name->entry_len);
    if (out_name->entry16 == nullptr) {
      return false;
    }
  }

  return true;
}

std::string ToFormattedResourceString(AssetManager2::ResourceName* resource_name) {
  std::string result;
  if (resource_name->package != nullptr) {
    result.append(resource_name->package, resource_name->package_len);
  }

  if (resource_name->type != nullptr || resource_name->type16 != nullptr) {
    if (!result.empty()) {
      result += ":";
    }

    if (resource_name->type != nullptr) {
      result.append(resource_name->type, resource_name->type_len);
    } else {
      result += util::Utf16ToUtf8(StringPiece16(resource_name->type16, resource_name->type_len));
    }
  }

  if (resource_name->entry != nullptr || resource_name->entry16 != nullptr) {
    if (!result.empty()) {
      result += "/";
    }

    if (resource_name->entry != nullptr) {
      result.append(resource_name->entry, resource_name->entry_len);
    } else {
      result += util::Utf16ToUtf8(StringPiece16(resource_name->entry16, resource_name->entry_len));
    }
  }

  return result;
}

}  // namespace android