Encoding of <overlayable> and <policy>

This change defines two new chunks for encoding overlayable information.
RES_TABLE_OVERLAYABLE_POLICY_TYPE contains flags that represent
restrictions enforced on overlays that try to overlay a specific set of
resource ids. The chunk header is followed by ResTable_ref for each id
that belongs to the policy type. A policy chunk will be created for
every unique combination of policies that are defined in overlayable
declarations.

RES_TABLE_OVERLAYABLE_TYPE holds policy blocks. Since <overlayable>
does not currently have any attributes, only one overlayable block is
encoded in an APK.

This change also removes the SPEC_OVERLAYABLE flag because the runtime
does not use the flag, and the overlayable chunk encoding renders it
obsolete.

Bug: 110869880
Bug: 117545186
Test: libandroidfw_tests and aapt2_tests
Change-Id: I45ae9bf4176699f14c85e2b7a2e8560185d8a0b8

1 files changed, 45 insertions, 4 deletions

diff --git a/libs/androidfw/tests/LoadedArsc_test.cpp b/libs/androidfw/tests/LoadedArsc_test.cpp
index ffa48367c252..441356b95d36 100644
--- a/libs/androidfw/tests/LoadedArsc_test.cpp
+++ b/libs/androidfw/tests/LoadedArsc_test.cpp
@@ -22,12 +22,14 @@
 #include "TestHelpers.h"
 #include "data/basic/R.h"
 #include "data/libclient/R.h"
+#include "data/overlayable/R.h"
 #include "data/sparse/R.h"
 #include "data/styles/R.h"
 
 namespace app = com::android::app;
 namespace basic = com::android::basic;
 namespace libclient = com::android::libclient;
+namespace overlayable = com::android::overlayable;
 namespace sparse = com::android::sparse;
 
 using ::android::base::ReadFileToString;
@@ -273,10 +275,44 @@ TEST(LoadedArscTest, LoadOverlay) {
   ASSERT_THAT(LoadedPackage::GetEntry(type_spec->types[0], 0x0000), NotNull());
 }
 
-// structs with size fields (like Res_value, ResTable_entry) should be
-// backwards and forwards compatible (aka checking the size field against
-// sizeof(Res_value) might not be backwards compatible.
-TEST(LoadedArscTest, LoadingShouldBeForwardsAndBackwardsCompatible) { ASSERT_TRUE(false); }
+TEST(LoadedArscTest, LoadOverlayable) {
+  std::string contents;
+  ASSERT_TRUE(ReadFileFromZipToString(GetTestDataPath() + "/overlayable/overlayable.apk",
+                                      "resources.arsc", &contents));
+
+  std::unique_ptr<const LoadedArsc> loaded_arsc =
+      LoadedArsc::Load(StringPiece(contents), nullptr /*loaded_idmap*/, false /*system*/,
+                       false /*load_as_shared_library*/);
+
+  ASSERT_THAT(loaded_arsc, NotNull());
+  const LoadedPackage* package = loaded_arsc->GetPackageById(
+      get_package_id(overlayable::R::string::not_overlayable));
+
+  const OverlayableInfo* info = package->GetOverlayableInfo(
+      overlayable::R::string::not_overlayable);
+  ASSERT_THAT(info, IsNull());
+
+  info = package->GetOverlayableInfo(overlayable::R::string::overlayable1);
+  ASSERT_THAT(info, NotNull());
+  EXPECT_THAT(info->policy_flags, Eq(ResTable_overlayable_policy_header::POLICY_PUBLIC));
+
+  info = package->GetOverlayableInfo(overlayable::R::string::overlayable2);
+  ASSERT_THAT(info, NotNull());
+  EXPECT_THAT(info->policy_flags,
+              Eq(ResTable_overlayable_policy_header::POLICY_SYSTEM_PARTITION
+                 | ResTable_overlayable_policy_header::POLICY_PRODUCT_PARTITION));
+
+  info = package->GetOverlayableInfo(overlayable::R::string::overlayable3);
+  ASSERT_THAT(info, NotNull());
+  EXPECT_THAT(info->policy_flags,
+              Eq(ResTable_overlayable_policy_header::POLICY_VENDOR_PARTITION
+                 | ResTable_overlayable_policy_header::POLICY_PRODUCT_SERVICES_PARTITION
+                 | ResTable_overlayable_policy_header::POLICY_PRODUCT_PARTITION));
+
+  info = package->GetOverlayableInfo(overlayable::R::string::overlayable4);
+  ASSERT_THAT(info, NotNull());
+  EXPECT_THAT(info->policy_flags, Eq(ResTable_overlayable_policy_header::POLICY_PUBLIC));
+}
 
 TEST(LoadedArscTest, ResourceIdentifierIterator) {
   std::string contents;
@@ -326,4 +362,9 @@ TEST(LoadedArscTest, ResourceIdentifierIterator) {
   ASSERT_EQ(end, iter);
 }
 
+// structs with size fields (like Res_value, ResTable_entry) should be
+// backwards and forwards compatible (aka checking the size field against
+// sizeof(Res_value) might not be backwards compatible.
+TEST(LoadedArscTest, LoadingShouldBeForwardsAndBackwardsCompatible) { ASSERT_TRUE(false); }
+
 }  // namespace android