AAPT2: Add a APK filtering.

Allow resource files to be removed from the final artifact based on the
density and locale configuration in the config file. The APK is split
along the density, locale and ABI axis. Each split is generated from the
original APK without modifying the original. The new resource table is
written back to the file system with unneeded assets etc removed.

Test: Unit tests
Test: Manually run optimize command against an APK and inspect results
Test: Installed split searchlite APK (after resigning) and ran on N6

Change-Id: If73597dcfd88c02d2616518585d0e25a5c6a84d1

1 files changed, 74 insertions, 22 deletions

diff --git a/tools/aapt2/configuration/ConfigurationParser.cpp b/tools/aapt2/configuration/ConfigurationParser.cpp
index b0ed792215df..a9d6da0258cb 100644
--- a/tools/aapt2/configuration/ConfigurationParser.cpp
+++ b/tools/aapt2/configuration/ConfigurationParser.cpp
@@ -59,6 +59,7 @@ using ::aapt::xml::XmlActionExecutor;
 using ::aapt::xml::XmlActionExecutorPolicy;
 using ::aapt::xml::XmlNodeAction;
 using ::android::base::ReadFileToString;
+using ::android::StringPiece;
 
 const std::unordered_map<std::string, Abi> kStringToAbiMap = {
     {"armeabi", Abi::kArmeV6}, {"armeabi-v7a", Abi::kArmV7a},  {"arm64-v8a", Abi::kArm64V8a},
@@ -117,9 +118,9 @@ const std::string& AbiToString(Abi abi) {
  * success, or false if the either the placeholder is not found in the name, or the value is not
  * present and the placeholder was.
  */
-static bool ReplacePlaceholder(const std::string& placeholder, const Maybe<std::string>& value,
+static bool ReplacePlaceholder(const StringPiece& placeholder, const Maybe<StringPiece>& value,
                                std::string* name, IDiagnostics* diag) {
-  size_t offset = name->find(placeholder);
+  size_t offset = name->find(placeholder.data());
   bool found = (offset != std::string::npos);
 
   // Make sure the placeholder was present if the desired value is present.
@@ -139,46 +140,86 @@ static bool ReplacePlaceholder(const std::string& placeholder, const Maybe<std::
     return false;
   }
 
-  name->replace(offset, placeholder.length(), value.value());
+  name->replace(offset, placeholder.length(), value.value().data());
 
   // Make sure there was only one instance of the placeholder.
-  if (name->find(placeholder) != std::string::npos) {
+  if (name->find(placeholder.data()) != std::string::npos) {
     diag->Error(DiagMessage() << "Placeholder present multiple times: " << placeholder);
     return false;
   }
   return true;
 }
 
-Maybe<std::string> Artifact::ToArtifactName(const std::string& format, IDiagnostics* diag) const {
-  std::string result = format;
+Maybe<std::string> Artifact::ToArtifactName(const StringPiece& format, IDiagnostics* diag,
+                                            const StringPiece& base_name,
+                                            const StringPiece& ext) const {
+  std::string result = format.to_string();
 
-  if (!ReplacePlaceholder("{abi}", abi_group, &result, diag)) {
+  Maybe<StringPiece> maybe_base_name =
+      base_name.empty() ? Maybe<StringPiece>{} : Maybe<StringPiece>{base_name};
+  if (!ReplacePlaceholder("${basename}", maybe_base_name, &result, diag)) {
     return {};
   }
 
-  if (!ReplacePlaceholder("{density}", screen_density_group, &result, diag)) {
+  // Extension is optional.
+  if (result.find("${ext}") != std::string::npos) {
+    if (!ReplacePlaceholder("${ext}", {ext}, &result, diag)) {
+      return {};
+    }
+  }
+
+  if (!ReplacePlaceholder("${abi}", abi_group, &result, diag)) {
+    return {};
+  }
+
+  if (!ReplacePlaceholder("${density}", screen_density_group, &result, diag)) {
     return {};
   }
 
-  if (!ReplacePlaceholder("{locale}", locale_group, &result, diag)) {
+  if (!ReplacePlaceholder("${locale}", locale_group, &result, diag)) {
     return {};
   }
 
-  if (!ReplacePlaceholder("{sdk}", android_sdk_group, &result, diag)) {
+  if (!ReplacePlaceholder("${sdk}", android_sdk_group, &result, diag)) {
     return {};
   }
 
-  if (!ReplacePlaceholder("{feature}", device_feature_group, &result, diag)) {
+  if (!ReplacePlaceholder("${feature}", device_feature_group, &result, diag)) {
     return {};
   }
 
-  if (!ReplacePlaceholder("{gl}", gl_texture_group, &result, diag)) {
+  if (!ReplacePlaceholder("${gl}", gl_texture_group, &result, diag)) {
     return {};
   }
 
   return result;
 }
 
+Maybe<std::string> Artifact::Name(const StringPiece& base_name, const StringPiece& ext,
+                                  IDiagnostics* diag) const {
+  if (!name) {
+    return {};
+  }
+
+  std::string result = name.value();
+
+  // Base name is optional.
+  if (result.find("${basename}") != std::string::npos) {
+    if (!ReplacePlaceholder("${basename}", {base_name}, &result, diag)) {
+      return {};
+    }
+  }
+
+  // Extension is optional.
+  if (result.find("${ext}") != std::string::npos) {
+    if (!ReplacePlaceholder("${ext}", {ext}, &result, diag)) {
+      return {};
+    }
+  }
+
+  return result;
+}
+
 }  // namespace configuration
 
 /** Returns a ConfigurationParser for the file located at the provided path. */
@@ -346,7 +387,10 @@ ConfigurationParser::ActionHandler ConfigurationParser::screen_density_group_han
         if ((t = NodeCast<xml::Text>(node.get())) != nullptr) {
           ConfigDescription config_descriptor;
           const android::StringPiece& text = TrimWhitespace(t->text);
-          if (ConfigDescription::Parse(text, &config_descriptor)) {
+          bool parsed = ConfigDescription::Parse(text, &config_descriptor);
+          if (parsed &&
+              (config_descriptor.CopyWithoutSdkVersion().diff(ConfigDescription::DefaultConfig()) ==
+               android::ResTable_config::CONFIG_DENSITY)) {
             // Copy the density with the minimum SDK version stripped out.
             group.push_back(config_descriptor.CopyWithoutSdkVersion());
           } else {
@@ -379,17 +423,25 @@ ConfigurationParser::ActionHandler ConfigurationParser::locale_group_handler_ =
                                 << child->name);
       valid = false;
     } else {
-      Locale entry;
-      for (const auto& attr : child->attributes) {
-        if (attr.name == "lang") {
-          entry.lang = {attr.value};
-        } else if (attr.name == "region") {
-          entry.region = {attr.value};
-        } else {
-          diag->Warn(DiagMessage() << "Unknown attribute: " << attr.name << " = " << attr.value);
+      for (auto& node : child->children) {
+        xml::Text* t;
+        if ((t = NodeCast<xml::Text>(node.get())) != nullptr) {
+          ConfigDescription config_descriptor;
+          const android::StringPiece& text = TrimWhitespace(t->text);
+          bool parsed = ConfigDescription::Parse(text, &config_descriptor);
+          if (parsed &&
+              (config_descriptor.CopyWithoutSdkVersion().diff(ConfigDescription::DefaultConfig()) ==
+               android::ResTable_config::CONFIG_LOCALE)) {
+            // Copy the locale with the minimum SDK version stripped out.
+            group.push_back(config_descriptor.CopyWithoutSdkVersion());
+          } else {
+            diag->Error(DiagMessage()
+                        << "Could not parse config descriptor for screen-density: " << text);
+            valid = false;
+          }
+          break;
         }
       }
-      group.push_back(entry);
     }
   }