Option to exclude configs from AAPT2 Link

Adds --exclude-configs to remove matching configs from resulting APK. This matches on explicitness, so if the resource contains all the flags set by the option exactly, it will be removed, but not the other way around.

"--exclude-configs fr" with fr-land resource will remove.
"--exclude-configs fr-land" with fr resource will not remove.

Bug: 119678846

Test: aapt2_tests ResourceExcluder_test
Test: manually ran link on a test set of res

Change-Id: Ieccdecde4aea1fa0502abfd092dffa7da8f929ea

6 files changed, 389 insertions, 0 deletions

diff --git a/tools/aapt2/Android.bp b/tools/aapt2/Android.bp
index 7783e108f674..6ac701ada70f 100644
--- a/tools/aapt2/Android.bp
+++ b/tools/aapt2/Android.bp
@@ -108,6 +108,7 @@ cc_library_host_static {
         "link/ProductFilter.cpp",
         "link/PrivateAttributeMover.cpp",
         "link/ReferenceLinker.cpp",
+        "link/ResourceExcluder.cpp",
         "link/TableMerger.cpp",
         "link/XmlCompatVersioner.cpp",
         "link/XmlNamespaceRemover.cpp",
diff --git a/tools/aapt2/cmd/Link.cpp b/tools/aapt2/cmd/Link.cpp
index 729447ee1de5..8463046a80eb 100644
--- a/tools/aapt2/cmd/Link.cpp
+++ b/tools/aapt2/cmd/Link.cpp
@@ -59,6 +59,7 @@
 #include "link/ManifestFixer.h"
 #include "link/NoDefaultResourceRemover.h"
 #include "link/ReferenceLinker.h"
+#include "link/ResourceExcluder.h"
 #include "link/TableMerger.h"
 #include "link/XmlCompatVersioner.h"
 #include "optimize/ResourceDeduper.h"
@@ -1828,6 +1829,29 @@ class Linker {
       }
     }
 
+    if (!options_.exclude_configs_.empty()) {
+      std::vector<ConfigDescription> excluded_configs;
+
+      for (auto& config_string : options_.exclude_configs_) {
+        ConfigDescription config_description;
+
+        if (!ConfigDescription::Parse(config_string, &config_description)) {
+          context_->GetDiagnostics()->Error(DiagMessage()
+                                                << "failed to parse --excluded-configs "
+                                                << config_string);
+          return 1;
+        }
+
+        excluded_configs.push_back(config_description);
+      }
+
+      ResourceExcluder excluder(excluded_configs);
+      if (!excluder.Consume(context_, &final_table_)) {
+        context_->GetDiagnostics()->Error(DiagMessage() << "failed excluding configurations");
+        return 1;
+      }
+    }
+
     if (!options_.no_resource_deduping) {
       ResourceDeduper deduper;
       if (!deduper.Consume(context_, &final_table_)) {
diff --git a/tools/aapt2/cmd/Link.h b/tools/aapt2/cmd/Link.h
index f70470acb3d8..590a6bb19e30 100644
--- a/tools/aapt2/cmd/Link.h
+++ b/tools/aapt2/cmd/Link.h
@@ -82,6 +82,9 @@ struct LinkOptions {
   std::vector<SplitConstraints> split_constraints;
   std::vector<std::string> split_paths;
 
+  // Configurations to exclude
+  std::vector<std::string> exclude_configs_;
+
   // Stable ID options.
   std::unordered_map<ResourceName, ResourceId> stable_id_map;
   Maybe<std::string> resource_id_map_path;
@@ -255,6 +258,9 @@ class LinkCommand : public Command {
             "Syntax: path/to/output.apk:<config>[,<config>[...]].\n"
             "On Windows, use a semicolon ';' separator instead.",
         &split_args_);
+    AddOptionalFlagList("--exclude-configs",
+        "Excludes values of resources whose configs contain the specified qualifiers.",
+        &options_.exclude_configs_);
     AddOptionalSwitch("--debug-mode",
         "Inserts android:debuggable=\"true\" in to the application node of the\n"
             "manifest, making the application debuggable even on production devices.",
diff --git a/tools/aapt2/link/ResourceExcluder.cpp b/tools/aapt2/link/ResourceExcluder.cpp
new file mode 100644
index 000000000000..2555995dfc8e
--- /dev/null
+++ b/tools/aapt2/link/ResourceExcluder.cpp
@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2019 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 "link/ResourceExcluder.h"
+
+#include <algorithm>
+
+#include "DominatorTree.h"
+#include "ResourceTable.h"
+
+using android::ConfigDescription;
+
+namespace aapt {
+
+namespace {
+
+void RemoveIfExcluded(std::set<std::pair<ConfigDescription, int>>& excluded_configs_,
+                      IAaptContext* context,
+                      ResourceEntry* entry,
+                      ResourceConfigValue* value) {
+  const ConfigDescription& config = value->config;
+
+  // If this entry is a default, ignore
+  if (config == ConfigDescription::DefaultConfig()) {
+    return;
+  }
+
+  for (auto& excluded_pair : excluded_configs_) {
+
+    const ConfigDescription& excluded_config = excluded_pair.first;
+    const int& excluded_diff = excluded_pair.second;
+
+    // Check whether config contains all flags in excluded config
+    int node_diff = config.diff(excluded_config);
+    int masked_diff = excluded_diff & node_diff;
+
+    if (masked_diff == 0) {
+      if (context->IsVerbose()) {
+        context->GetDiagnostics()->Note(
+            DiagMessage(value->value->GetSource())
+                << "excluded resource \""
+                << entry->name
+                << "\" with config "
+                << config.toString());
+      }
+      value->value = {};
+      return;
+    }
+  }
+}
+
+}  // namespace
+
+bool ResourceExcluder::Consume(IAaptContext* context, ResourceTable* table) {
+  for (auto& package : table->packages) {
+    for (auto& type : package->types) {
+      for (auto& entry : type->entries) {
+        for (auto& value : entry->values) {
+          RemoveIfExcluded(excluded_configs_, context, entry.get(), value.get());
+        }
+
+        // Erase the values that were removed.
+        entry->values.erase(
+            std::remove_if(
+                entry->values.begin(), entry->values.end(),
+                [](const std::unique_ptr<ResourceConfigValue>& val) -> bool {
+                  return val == nullptr || val->value == nullptr;
+                }),
+            entry->values.end());
+      }
+    }
+  }
+  return true;
+}
+
+}  // namespace aapt
diff --git a/tools/aapt2/link/ResourceExcluder.h b/tools/aapt2/link/ResourceExcluder.h
new file mode 100644
index 000000000000..1890b34ae7c5
--- /dev/null
+++ b/tools/aapt2/link/ResourceExcluder.h
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2019 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 AAPT_LINK_RESOURCEEXCLUDER_H
+#define AAPT_LINK_RESOURCEEXCLUDER_H
+
+#include "android-base/macros.h"
+
+#include "process/IResourceTableConsumer.h"
+
+using android::ConfigDescription;
+
+namespace aapt {
+
+// Removes excluded configs from resources.
+class ResourceExcluder : public IResourceTableConsumer {
+ public:
+  explicit ResourceExcluder(std::vector<ConfigDescription>& excluded_configs) {
+    for (auto& config: excluded_configs) {
+      int diff_from_default = config.diff(ConfigDescription::DefaultConfig());
+      excluded_configs_.insert(std::pair(config, diff_from_default));
+    }
+  }
+
+  bool Consume(IAaptContext* context, ResourceTable* table) override;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ResourceExcluder);
+
+  std::set<std::pair<ConfigDescription, int>> excluded_configs_;
+};
+
+} // namespace aapt
+
+#endif  // AAPT_LINK_RESOURCEEXCLUDER_H
diff --git a/tools/aapt2/link/ResourceExcluder_test.cpp b/tools/aapt2/link/ResourceExcluder_test.cpp
new file mode 100644
index 000000000000..c9d01e49aeae
--- /dev/null
+++ b/tools/aapt2/link/ResourceExcluder_test.cpp
@@ -0,0 +1,221 @@
+/*
+ * Copyright (C) 2019 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 "link/ResourceExcluder.h"
+
+#include "ResourceTable.h"
+#include "test/Test.h"
+
+using ::aapt::test::HasValue;
+using ::android::ConfigDescription;
+using ::testing::Not;
+
+namespace {
+
+ConfigDescription BuildArg(const std::string arg) {
+  ConfigDescription config_description;
+  ConfigDescription::Parse(arg, &config_description);
+  return config_description;
+}
+
+std::vector<ConfigDescription> BuildArgList(const std::string arg) {
+  ConfigDescription config_description;
+  ConfigDescription::Parse(arg, &config_description);
+  return { config_description };
+}
+
+} // namespace
+
+namespace aapt {
+
+TEST(ResourceExcluderTest, NonMatchConfigNotExcluded) {
+  std::unique_ptr<IAaptContext> context = test::ContextBuilder().Build();
+  ConfigDescription default_config;
+  auto fr_config = test::ParseConfigOrDie("fr");
+
+  std::unique_ptr<ResourceTable> table =
+      test::ResourceTableBuilder()
+          .AddString("android:string/test", ResourceId{}, default_config, "default")
+          .AddString("android:string/test", ResourceId{}, fr_config, "fr")
+          .Build();
+
+  auto args = BuildArgList("en");
+
+  ASSERT_TRUE(ResourceExcluder(args).Consume(context.get(), table.get()));
+  EXPECT_THAT(table, HasValue("android:string/test", default_config));
+  EXPECT_THAT(table, HasValue("android:string/test", fr_config));
+}
+
+TEST(ResourceExcluderTest, ExactConfigExcluded) {
+  std::unique_ptr<IAaptContext> context = test::ContextBuilder().Build();
+  ConfigDescription default_config;
+  auto fr_config = test::ParseConfigOrDie("fr");
+
+  std::unique_ptr<ResourceTable> table =
+      test::ResourceTableBuilder()
+          .AddString("android:string/test", ResourceId{}, default_config, "default")
+          .AddString("android:string/test", ResourceId{}, fr_config, "fr")
+          .Build();
+
+  auto args = BuildArgList("fr");
+
+  ASSERT_TRUE(ResourceExcluder(args).Consume(context.get(), table.get()));
+  EXPECT_THAT(table, HasValue("android:string/test", default_config));
+  EXPECT_THAT(table, Not(HasValue("android:string/test", fr_config)));
+}
+
+TEST(ResourceExcluderTest, MoreSpecificConfigExcluded) {
+  std::unique_ptr<IAaptContext> context = test::ContextBuilder().Build();
+  ConfigDescription default_config;
+  auto fr_land_config = test::ParseConfigOrDie("fr-land");
+
+  std::unique_ptr<ResourceTable> table =
+      test::ResourceTableBuilder()
+          .AddString("android:string/test", ResourceId{}, default_config, "default")
+          .AddString("android:string/test", ResourceId{}, fr_land_config, "fr-land")
+          .Build();
+
+  auto args = BuildArgList("fr");
+
+  ASSERT_TRUE(ResourceExcluder(args).Consume(context.get(), table.get()));
+  EXPECT_THAT(table, HasValue("android:string/test", default_config));
+  EXPECT_THAT(table, Not(HasValue("android:string/test", fr_land_config)));
+}
+
+TEST(ResourceExcluderTest, MultipleMoreSpecificConfigExcluded) {
+  std::unique_ptr<IAaptContext> context = test::ContextBuilder().Build();
+  ConfigDescription default_config;
+  auto night_config = test::ParseConfigOrDie("night");
+  auto fr_config = test::ParseConfigOrDie("fr");
+  auto fr_land_config = test::ParseConfigOrDie("fr-land");
+  auto fr_night_config = test::ParseConfigOrDie("fr-night");
+
+  std::unique_ptr<ResourceTable> table =
+      test::ResourceTableBuilder()
+          .AddString("android:string/test", ResourceId{}, default_config, "default")
+          .AddString("android:string/test", ResourceId{}, night_config, "night")
+          .AddString("android:string/test", ResourceId{}, fr_config, "fr")
+          .AddString("android:string/test", ResourceId{}, fr_land_config, "fr-land")
+          .AddString("android:string/test", ResourceId{}, fr_night_config, "fr-night")
+          .Build();
+
+  auto args = BuildArgList("fr");
+
+  ASSERT_TRUE(ResourceExcluder(args).Consume(context.get(), table.get()));
+  EXPECT_THAT(table, HasValue("android:string/test", default_config));
+  EXPECT_THAT(table, HasValue("android:string/test", night_config));
+  EXPECT_THAT(table, Not(HasValue("android:string/test", fr_config)));
+  EXPECT_THAT(table, Not(HasValue("android:string/test", fr_land_config)));
+  EXPECT_THAT(table, Not(HasValue("android:string/test", fr_night_config)));
+}
+
+TEST(ResourceExcluderTest, MultipleConfigsExcluded) {
+  std::unique_ptr<IAaptContext> context = test::ContextBuilder().Build();
+  ConfigDescription default_config;
+  auto night_config = test::ParseConfigOrDie("night");
+  auto fr_config = test::ParseConfigOrDie("fr");
+  auto fr_land_config = test::ParseConfigOrDie("fr-land");
+  auto fr_night_config = test::ParseConfigOrDie("fr-night");
+
+  std::unique_ptr<ResourceTable> table =
+      test::ResourceTableBuilder()
+          .AddString("android:string/test", ResourceId{}, default_config, "default")
+          .AddString("android:string/test", ResourceId{}, night_config, "night")
+          .AddString("android:string/test", ResourceId{}, fr_config, "fr")
+          .AddString("android:string/test", ResourceId{}, fr_land_config, "fr-land")
+          .AddString("android:string/test", ResourceId{}, fr_night_config, "fr-night")
+          .Build();
+
+  std::vector<ConfigDescription> args;
+  args.push_back(BuildArg("land"));
+  args.push_back(BuildArg("night"));
+
+  ASSERT_TRUE(ResourceExcluder(args).Consume(context.get(), table.get()));
+  EXPECT_THAT(table, HasValue("android:string/test", default_config));
+  EXPECT_THAT(table, Not(HasValue("android:string/test", night_config)));
+  EXPECT_THAT(table, HasValue("android:string/test", fr_config));
+  EXPECT_THAT(table, Not(HasValue("android:string/test", fr_land_config)));
+  EXPECT_THAT(table, Not(HasValue("android:string/test", fr_night_config)));
+}
+
+TEST(ResourceExcluderTest, LessSpecificConfigNotExcluded) {
+  std::unique_ptr<IAaptContext> context = test::ContextBuilder().Build();
+  ConfigDescription default_config;
+  auto fr_config = test::ParseConfigOrDie("fr");
+  auto fr_land_config = test::ParseConfigOrDie("fr-land");
+
+  std::unique_ptr<ResourceTable> table =
+      test::ResourceTableBuilder()
+          .AddString("android:string/test", ResourceId{}, default_config, "default")
+          .AddString("android:string/test", ResourceId{}, fr_config, "fr")
+          .AddString("android:string/test", ResourceId{}, fr_land_config, "fr-land")
+          .Build();
+
+  auto args = BuildArgList("fr-land");
+
+  ASSERT_TRUE(ResourceExcluder(args).Consume(context.get(), table.get()));
+  EXPECT_THAT(table, HasValue("android:string/test", default_config));
+  EXPECT_THAT(table, HasValue("android:string/test", fr_config));
+  EXPECT_THAT(table, Not(HasValue("android:string/test", fr_land_config)));
+}
+
+TEST(ResourceExcluderTest, LowerPrecedenceStillExcludes) {
+  std::unique_ptr<IAaptContext> context = test::ContextBuilder().Build();
+  ConfigDescription default_config;
+  auto fr_config = test::ParseConfigOrDie("fr");
+  auto fr_night_config = test::ParseConfigOrDie("fr-night");
+
+  std::unique_ptr<ResourceTable> table =
+      test::ResourceTableBuilder()
+          .AddString("android:string/test", ResourceId{}, default_config, "default")
+          .AddString("android:string/test", ResourceId{}, fr_config, "fr")
+          .AddString("android:string/test", ResourceId{}, fr_night_config, "fr-night")
+          .Build();
+
+  // "night" is lower precedence than "fr"
+  auto args = BuildArgList("night");
+
+  ASSERT_TRUE(ResourceExcluder(args).Consume(context.get(), table.get()));
+  EXPECT_THAT(table, HasValue("android:string/test", default_config));
+  EXPECT_THAT(table, HasValue("android:string/test", fr_config));
+  EXPECT_THAT(table, Not(HasValue("android:string/test", fr_night_config)));
+}
+
+TEST(ResourceExcluderTest, OnlyExcludesSpecificTier) {
+  std::unique_ptr<IAaptContext> context = test::ContextBuilder().Build();
+  ConfigDescription default_config;
+  auto mdpi_config = test::ParseConfigOrDie("mdpi");
+  auto hdpi_config = test::ParseConfigOrDie("hdpi");
+  auto xhdpi_config = test::ParseConfigOrDie("xhdpi");
+
+  std::unique_ptr<ResourceTable> table =
+      test::ResourceTableBuilder()
+          .AddString("android:string/test", ResourceId{}, default_config, "default")
+          .AddString("android:string/test", ResourceId{}, mdpi_config, "mdpi")
+          .AddString("android:string/test", ResourceId{}, hdpi_config, "hdpi")
+          .AddString("android:string/test", ResourceId{}, xhdpi_config, "xhdpi")
+          .Build();
+
+  auto args = BuildArgList("hdpi");
+
+  ASSERT_TRUE(ResourceExcluder(args).Consume(context.get(), table.get()));
+  EXPECT_THAT(table, HasValue("android:string/test", default_config));
+  EXPECT_THAT(table, HasValue("android:string/test", mdpi_config));
+  EXPECT_THAT(table, Not(HasValue("android:string/test", hdpi_config)));
+  EXPECT_THAT(table, HasValue("android:string/test", xhdpi_config));
+}
+
+}  // namespace aapt