Fix loaded apk string pool order

Loading in an APk changed the ordering of strings in the string pool.
When loading an apk, assign the strings to the same index as they
are in the ResStringPool.

Bug: 118831219
Test: "aapt2 dump strings left.apk" prints in the correct order,
"aapt2 convert left.apk --output-format binary -o left_binary.apk" has
entries in the correct order, and aapt2_tests

Change-Id: I00014c02195f39c1152a110e90083d9b14e9216e

1 files changed, 17 insertions, 5 deletions

diff --git a/tools/aapt2/StringPool.cpp b/tools/aapt2/StringPool.cpp
index 8eabd3225d87..a8c26668b3a5 100644
--- a/tools/aapt2/StringPool.cpp
+++ b/tools/aapt2/StringPool.cpp
@@ -165,12 +165,13 @@ StringPool::Ref StringPool::MakeRef(const StringPiece& str) {
   return MakeRefImpl(str, Context{}, true);
 }
 
-StringPool::Ref StringPool::MakeRef(const StringPiece& str, const Context& context) {
-  return MakeRefImpl(str, context, true);
+StringPool::Ref StringPool::MakeRef(const StringPiece& str, const Context& context,
+                                    Maybe<size_t> index) {
+  return MakeRefImpl(str, context, true, index);
 }
 
 StringPool::Ref StringPool::MakeRefImpl(const StringPiece& str, const Context& context,
-                                        bool unique) {
+                                        bool unique, Maybe<size_t> index) {
   if (unique) {
     auto range = indexed_strings_.equal_range(str);
     for (auto iter = range.first; iter != range.second; ++iter) {
@@ -180,15 +181,26 @@ StringPool::Ref StringPool::MakeRefImpl(const StringPiece& str, const Context& c
     }
   }
 
+  const size_t size = strings_.size();
+  // Insert the string at the end of the string vector if no index is specified
+  const size_t insertion_index = index ? index.value() : size;
+
   std::unique_ptr<Entry> entry(new Entry());
   entry->value = str.to_string();
   entry->context = context;
-  entry->index_ = strings_.size();
+  entry->index_ = insertion_index;
   entry->ref_ = 0;
   entry->pool_ = this;
 
   Entry* borrow = entry.get();
-  strings_.emplace_back(std::move(entry));
+  if (insertion_index == size) {
+    strings_.emplace_back(std::move(entry));
+  } else {
+    // Allocate enough space for the string at the index
+    strings_.resize(std::max(insertion_index + 1, size));
+    strings_[insertion_index] = std::move(entry);
+  }
+
   indexed_strings_.insert(std::make_pair(StringPiece(borrow->value), borrow));
   return Ref(borrow);
 }