tools/aapt2/cmd/Optimize.h

/*
 * Copyright (C) 2018 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.
 */

#ifndef AAPT2_OPTIMIZE_H
#define AAPT2_OPTIMIZE_H

#include "AppInfo.h"
#include "Command.h"
#include "configuration/ConfigurationParser.h"
#include "format/binary/TableFlattener.h"
#include "split/TableSplitter.h"

namespace aapt {

struct OptimizeOptions {
  // Path to the output APK.
  std::optional<std::string> output_path;
  // Path to the output APK directory for splits.
  std::optional<std::string> output_dir;

  // Details of the app extracted from the AndroidManifest.xml
  AppInfo app_info;

  // Exclude list of unused resources that should be removed from the apk.
  std::unordered_set<ResourceName> resources_exclude_list;

  // Split APK options.
  TableSplitterOptions table_splitter_options;

  // List of output split paths. These are in the same order as `split_constraints`.
  std::vector<std::string> split_paths;

  // List of SplitConstraints governing what resources go into each split. Ordered by `split_paths`.
  std::vector<SplitConstraints> split_constraints;

  TableFlattenerOptions table_flattener_options;

  std::optional<std::vector<aapt::configuration::OutputArtifact>> apk_artifacts;

  // Set of artifacts to keep when generating multi-APK splits. If the list is empty, all artifacts
  // are kept and will be written as output.
  std::unordered_set<std::string> kept_artifacts;

  // Whether or not to shorten resource paths in the APK.
  bool shorten_resource_paths = false;

  // Path to the output map of original resource paths to shortened paths.
  // TODO(b/246489170): keep the old option and format until transform to the new one
  std::optional<std::string> shortened_paths_map_path;

  // Whether sparse encoding should be used for O+ resources.
  bool enable_sparse_encoding = false;

  // Whether sparse encoding should be used for all resources.
  bool force_sparse_encoding = false;

  // Path to the output map of original resource paths/names to obfuscated paths/names.
  std::optional<std::string> obfuscation_map_path;
};

class OptimizeCommand : public Command {
 public:
  explicit OptimizeCommand() : Command("optimize") {
    SetDescription("Preforms resource optimizations on an apk.");
    AddOptionalFlag("-o", "Path to the output APK.", &options_.output_path, Command::kPath);
    AddOptionalFlag("-d", "Path to the output directory (for splits).", &options_.output_dir,
        Command::kPath);
    AddOptionalFlag("-x", "Path to XML configuration file.", &config_path_, Command::kPath);
    AddOptionalSwitch("-p", "Print the multi APK artifacts and exit.", &print_only_);
    AddOptionalFlag(
        "--target-densities",
        "Comma separated list of the screen densities that the APK will be optimized for.\n"
            "All the resources that would be unused on devices of the given densities will be \n"
            "removed from the APK.",
        &target_densities_);
    AddOptionalFlag("--resources-config-path",
        "Path to the resources.cfg file containing the list of resources and \n"
            "directives to each resource. \n"
            "Format: type/resource_name#[directive][,directive]",
        &resources_config_path_);
    AddOptionalFlagList("-c",
        "Comma separated list of configurations to include. The default\n"
            "is all configurations.",
        &configs_);
    AddOptionalFlagList("--split",
        "Split resources matching a set of configs out to a "
            "Split APK.\nSyntax: path/to/output.apk;<config>[,<config>[...]].\n"
            "On Windows, use a semicolon ';' separator instead.",
        &split_args_);
    AddOptionalFlagList("--keep-artifacts",
        "Comma separated list of artifacts to keep. If none are specified,\n"
            "all artifacts will be kept.",
        &kept_artifacts_);
    AddOptionalSwitch(
        "--enable-sparse-encoding",
        "Enables encoding sparse entries using a binary search tree.\n"
        "This decreases APK size at the cost of resource retrieval performance.\n"
        "Only applies sparse encoding to Android O+ resources or all resources if minSdk of "
        "the APK is O+",
        &options_.enable_sparse_encoding);
    AddOptionalSwitch("--force-sparse-encoding",
                      "Enables encoding sparse entries using a binary search tree.\n"
                      "This decreases APK size at the cost of resource retrieval performance.\n"
                      "Applies sparse encoding to all resources regardless of minSdk.",
                      &options_.force_sparse_encoding);
    AddOptionalSwitch(
        "--enable-compact-entries",
        "This decreases APK size by using compact resource entries for simple data types.",
        &options_.table_flattener_options.use_compact_entries);
    AddOptionalSwitch("--collapse-resource-names",
        "Collapses resource names to a single value in the key string pool. Resources can \n"
            "be exempted using the \"no_collapse\" directive in a file specified by "
            "--resources-config-path.",
        &options_.table_flattener_options.collapse_key_stringpool);
    AddOptionalSwitch("--shorten-resource-paths",
        "Shortens the paths of resources inside the APK. Resources can be exempted using the \n"
        "\"no_path_shorten\" directive in a file specified by --resources-config-path.",
        &options_.shorten_resource_paths);
    // TODO(b/246489170): keep the old option and format until transform to the new one
    AddOptionalFlag("--resource-path-shortening-map",
                    "[Deprecated]Path to output the map of old resource paths to shortened paths.",
                    &options_.shortened_paths_map_path);
    AddOptionalFlag("--save-obfuscation-map",
                    "Path to output the map of original paths/names to obfuscated paths/names.",
                    &options_.obfuscation_map_path);
    AddOptionalSwitch(
        "--deduplicate-entry-values",
        "Whether to deduplicate pairs of resource entry and value for simple resources.\n"
        "This is recommended to be used together with '--collapse-resource-names' flag or for\n"
        "APKs where resource names are manually collapsed. For such APKs this flag allows to\n"
        "store the same resource value only once in resource table which decreases APK size.\n"
        "Has no effect on APKs where resource names are kept.",
        &options_.table_flattener_options.deduplicate_entry_values);
    AddOptionalSwitch("-v", "Enables verbose logging", &verbose_);
  }

  int Action(const std::vector<std::string>& args) override;

 private:
  OptimizeOptions options_;

  bool WriteObfuscatedPathsMap(const std::map<std::string, std::string> &path_map,
                               const std::string &file_path);

  std::optional<std::string> config_path_;
  std::optional<std::string> resources_config_path_;
  std::optional<std::string> target_densities_;
  std::vector<std::string> configs_;
  std::vector<std::string> split_args_;
  std::unordered_set<std::string> kept_artifacts_;
  bool print_only_ = false;
  bool verbose_ = false;
};

}// namespace aapt

#endif //AAPT2_OPTIMIZE_H