AAPT2: Propagate SPEC_OVERLAYABLE flag to final APK

Resources can be marked as overlayable, which means they can
be overlaid by runtime resource overlays.

This change propagates this state to the final resource table that
is installed on device.

Future work:
- Have the idmap tool respect the overlayable state and ignore
  entries that overlay anything else.

Bug: 64980941
Test: make aapt2_tests
Change-Id: Id45b1e141a281be2ee32a4ac3096fcf1114d523b

1 files changed, 55 insertions, 10 deletions

diff --git a/tools/aapt2/format/binary/BinaryResourceParser.cpp b/tools/aapt2/format/binary/BinaryResourceParser.cpp
index 5078678e08a3..8d079ffecb63 100644
--- a/tools/aapt2/format/binary/BinaryResourceParser.cpp
+++ b/tools/aapt2/format/binary/BinaryResourceParser.cpp
@@ -223,7 +223,7 @@ bool BinaryResourceParser::ParsePackage(const ResChunk_header* chunk) {
         break;
 
       case android::RES_TABLE_TYPE_SPEC_TYPE:
-        if (!ParseTypeSpec(parser.chunk())) {
+        if (!ParseTypeSpec(package, parser.chunk())) {
           return false;
         }
         break;
@@ -260,7 +260,8 @@ bool BinaryResourceParser::ParsePackage(const ResChunk_header* chunk) {
   return true;
 }
 
-bool BinaryResourceParser::ParseTypeSpec(const ResChunk_header* chunk) {
+bool BinaryResourceParser::ParseTypeSpec(const ResourceTablePackage* package,
+                                         const ResChunk_header* chunk) {
   if (type_pool_.getError() != NO_ERROR) {
     diag_->Error(DiagMessage(source_) << "missing type string pool");
     return false;
@@ -276,6 +277,34 @@ bool BinaryResourceParser::ParseTypeSpec(const ResChunk_header* chunk) {
     diag_->Error(DiagMessage(source_) << "ResTable_typeSpec has invalid id: " << type_spec->id);
     return false;
   }
+
+  // The data portion of this chunk contains entry_count 32bit entries,
+  // each one representing a set of flags.
+  const size_t entry_count = dtohl(type_spec->entryCount);
+
+  // There can only be 2^16 entries in a type, because that is the ID
+  // space for entries (EEEE) in the resource ID 0xPPTTEEEE.
+  if (entry_count > std::numeric_limits<uint16_t>::max()) {
+    diag_->Error(DiagMessage(source_)
+                 << "ResTable_typeSpec has too many entries (" << entry_count << ")");
+    return false;
+  }
+
+  const size_t data_size = util::DeviceToHost32(type_spec->header.size) -
+                           util::DeviceToHost16(type_spec->header.headerSize);
+  if (entry_count * sizeof(uint32_t) > data_size) {
+    diag_->Error(DiagMessage(source_) << "ResTable_typeSpec too small to hold entries.");
+    return false;
+  }
+
+  // Record the type_spec_flags for later. We don't know resource names yet, and we need those
+  // to mark resources as overlayable.
+  const uint32_t* type_spec_flags = reinterpret_cast<const uint32_t*>(
+      reinterpret_cast<uintptr_t>(type_spec) + util::DeviceToHost16(type_spec->header.headerSize));
+  for (size_t i = 0; i < entry_count; i++) {
+    ResourceId id(package->id.value_or_default(0x0), type_spec->id, static_cast<size_t>(i));
+    entry_type_spec_flags_[id] = util::DeviceToHost32(type_spec_flags[i]);
+  }
   return true;
 }
 
@@ -346,18 +375,34 @@ bool BinaryResourceParser::ParseType(const ResourceTablePackage* package,
       return false;
     }
 
-    if (!table_->AddResourceAllowMangled(name, res_id, config, {}, std::move(resource_value),
-                                         diag_)) {
+    if (!table_->AddResourceWithIdMangled(name, res_id, config, {}, std::move(resource_value),
+                                          diag_)) {
       return false;
     }
 
-    if ((entry->flags & ResTable_entry::FLAG_PUBLIC) != 0) {
-      Symbol symbol;
-      symbol.state = SymbolState::kPublic;
-      symbol.source = source_.WithLine(0);
-      if (!table_->SetSymbolStateAllowMangled(name, res_id, symbol, diag_)) {
-        return false;
+    const uint32_t type_spec_flags = entry_type_spec_flags_[res_id];
+    if ((entry->flags & ResTable_entry::FLAG_PUBLIC) != 0 ||
+        (type_spec_flags & ResTable_typeSpec::SPEC_OVERLAYABLE) != 0) {
+      if (entry->flags & ResTable_entry::FLAG_PUBLIC) {
+        Visibility visibility;
+        visibility.level = Visibility::Level::kPublic;
+        visibility.source = source_.WithLine(0);
+        if (!table_->SetVisibilityWithIdMangled(name, visibility, res_id, diag_)) {
+          return false;
+        }
+      }
+
+      if (type_spec_flags & ResTable_typeSpec::SPEC_OVERLAYABLE) {
+        Overlayable overlayable;
+        overlayable.source = source_.WithLine(0);
+        if (!table_->SetOverlayableMangled(name, overlayable, diag_)) {
+          return false;
+        }
       }
+
+      // Erase the ID from the map once processed, so that we don't mark the same symbol more than
+      // once.
+      entry_type_spec_flags_.erase(res_id);
     }
 
     // Add this resource name->id mapping to the index so