[res] Store the number of types in typeSpec

Bug: 282215580
Test: build + boot + perf record

Change-Id: Ide34e48f8ba63a38a93f0a15618d601857498683

3 files changed, 26 insertions, 17 deletions

diff --git a/libs/androidfw/LoadedArsc.cpp b/libs/androidfw/LoadedArsc.cpp
index c9d5e074271b..02707e0e0c73 100644
--- a/libs/androidfw/LoadedArsc.cpp
+++ b/libs/androidfw/LoadedArsc.cpp
@@ -21,6 +21,7 @@
 #include <algorithm>
 #include <cstddef>
 #include <limits>
+#include <optional>
 
 #include "android-base/logging.h"
 #include "android-base/stringprintf.h"
@@ -50,7 +51,9 @@ namespace {
 // contiguous block of memory to store both the TypeSpec struct and
 // the Type structs.
 struct TypeSpecBuilder {
-  explicit TypeSpecBuilder(incfs::verified_map_ptr<ResTable_typeSpec> header) : header_(header) {}
+  explicit TypeSpecBuilder(incfs::verified_map_ptr<ResTable_typeSpec> header) : header_(header) {
+    type_entries.reserve(dtohs(header_->typesCount));
+  }
 
   void AddType(incfs::verified_map_ptr<ResTable_type> type) {
     TypeSpec::TypeEntry& entry = type_entries.emplace_back();
@@ -59,6 +62,7 @@ struct TypeSpecBuilder {
   }
 
   TypeSpec Build() {
+    type_entries.shrink_to_fit();
     return {header_, std::move(type_entries)};
   }
 
@@ -499,7 +503,7 @@ std::unique_ptr<const LoadedPackage> LoadedPackage::Load(const Chunk& chunk,
   // A map of TypeSpec builders, each associated with an type index.
   // We use these to accumulate the set of Types available for a TypeSpec, and later build a single,
   // contiguous block of memory that holds all the Types together with the TypeSpec.
-  std::unordered_map<int, std::unique_ptr<TypeSpecBuilder>> type_builder_map;
+  std::unordered_map<int, std::optional<TypeSpecBuilder>> type_builder_map;
 
   ChunkIterator iter(chunk.data_ptr(), chunk.data_size());
   while (iter.HasNext()) {
@@ -567,14 +571,14 @@ std::unique_ptr<const LoadedPackage> LoadedPackage::Load(const Chunk& chunk,
           return {};
         }
 
-        if (entry_count * sizeof(uint32_t) > chunk.data_size()) {
+        if (entry_count * sizeof(uint32_t) > child_chunk.data_size()) {
           LOG(ERROR) << "RES_TABLE_TYPE_SPEC_TYPE too small to hold entries.";
           return {};
         }
 
-        std::unique_ptr<TypeSpecBuilder>& builder_ptr = type_builder_map[type_spec->id];
-        if (builder_ptr == nullptr) {
-          builder_ptr = util::make_unique<TypeSpecBuilder>(type_spec.verified());
+        auto& maybe_type_builder = type_builder_map[type_spec->id];
+        if (!maybe_type_builder) {
+          maybe_type_builder.emplace(type_spec.verified());
           loaded_package->resource_ids_.set(type_spec->id, entry_count);
         } else {
           LOG(WARNING) << StringPrintf("RES_TABLE_TYPE_SPEC_TYPE already defined for ID %02x",
@@ -594,9 +598,9 @@ std::unique_ptr<const LoadedPackage> LoadedPackage::Load(const Chunk& chunk,
         }
 
         // Type chunks must be preceded by their TypeSpec chunks.
-        std::unique_ptr<TypeSpecBuilder>& builder_ptr = type_builder_map[type->id];
-        if (builder_ptr != nullptr) {
-          builder_ptr->AddType(type.verified());
+        auto& maybe_type_builder = type_builder_map[type->id];
+        if (maybe_type_builder) {
+          maybe_type_builder->AddType(type.verified());
         } else {
           LOG(ERROR) << StringPrintf(
               "RES_TABLE_TYPE_TYPE with ID %02x found without preceding RES_TABLE_TYPE_SPEC_TYPE.",
diff --git a/libs/androidfw/include/androidfw/ResourceTypes.h b/libs/androidfw/include/androidfw/ResourceTypes.h
index c0514fdff469..44ab14a8a7ac 100644
--- a/libs/androidfw/include/androidfw/ResourceTypes.h
+++ b/libs/androidfw/include/androidfw/ResourceTypes.h
@@ -1401,8 +1401,8 @@ struct ResTable_typeSpec
     
     // Must be 0.
     uint8_t res0;
-    // Must be 0.
-    uint16_t res1;
+    // Used to be reserved, if >0 specifies the number of ResTable_type entries for this spec.
+    uint16_t typesCount;
     
     // Number of uint32_t entry configuration masks that follow.
     uint32_t entryCount;
diff --git a/tools/aapt2/format/binary/TableFlattener.cpp b/tools/aapt2/format/binary/TableFlattener.cpp
index f05611048caa..1a82021bce71 100644
--- a/tools/aapt2/format/binary/TableFlattener.cpp
+++ b/tools/aapt2/format/binary/TableFlattener.cpp
@@ -381,9 +381,9 @@ class PackageFlattener {
     return true;
   }
 
-  bool FlattenTypeSpec(const ResourceTableTypeView& type,
-                       const std::vector<ResourceTableEntryView>& sorted_entries,
-                       BigBuffer* buffer) {
+  ResTable_typeSpec* FlattenTypeSpec(const ResourceTableTypeView& type,
+                                     const std::vector<ResourceTableEntryView>& sorted_entries,
+                                     BigBuffer* buffer) {
     ChunkWriter type_spec_writer(buffer);
     ResTable_typeSpec* spec_header =
         type_spec_writer.StartChunk<ResTable_typeSpec>(RES_TABLE_TYPE_SPEC_TYPE);
@@ -391,7 +391,7 @@ class PackageFlattener {
 
     if (sorted_entries.empty()) {
       type_spec_writer.Finish();
-      return true;
+      return spec_header;
     }
 
     // We can't just take the size of the vector. There may be holes in the
@@ -427,7 +427,7 @@ class PackageFlattener {
       }
     }
     type_spec_writer.Finish();
-    return true;
+    return spec_header;
   }
 
   bool FlattenTypes(BigBuffer* buffer) {
@@ -450,7 +450,8 @@ class PackageFlattener {
       expected_type_id++;
       type_pool_.MakeRef(type.named_type.to_string());
 
-      if (!FlattenTypeSpec(type, type.entries, buffer)) {
+      const auto type_spec_header = FlattenTypeSpec(type, type.entries, buffer);
+      if (!type_spec_header) {
         return false;
       }
 
@@ -511,6 +512,10 @@ class PackageFlattener {
           return false;
         }
       }
+
+      // And now we can update the type entries count in the typeSpec header.
+      type_spec_header->typesCount = android::util::HostToDevice16(uint16_t(std::min<uint32_t>(
+          config_to_entry_list_map.size(), std::numeric_limits<uint16_t>::max())));
     }
     return true;
   }