IsFabricatedOverlay() optimization

This function is used mostly to select what type should
be parsing the very same file, so instead of opening that file
again later make it able to accept an opened fd

Bug: 237583012
Test: build + boot
Change-Id: I9ca1f44d6fe16fec0dd4732bfc9f0d6272d3b1e7

1 files changed, 5 insertions, 4 deletions

diff --git a/libs/androidfw/ApkAssets.cpp b/libs/androidfw/ApkAssets.cpp
index 9aa37872b8de..c0fa63a08fac 100755
--- a/libs/androidfw/ApkAssets.cpp
+++ b/libs/androidfw/ApkAssets.cpp
@@ -83,15 +83,16 @@ std::unique_ptr<ApkAssets> ApkAssets::LoadOverlay(const std::string& idmap_path,
     return {};
   }
 
+  std::string overlay_path(loaded_idmap->OverlayApkPath());
+  auto fd = unique_fd(::open(overlay_path.c_str(), O_RDONLY|O_CLOEXEC));
   std::unique_ptr<AssetsProvider> overlay_assets;
-  const std::string overlay_path(loaded_idmap->OverlayApkPath());
-  if (IsFabricatedOverlay(overlay_path)) {
+  if (IsFabricatedOverlay(fd)) {
     // Fabricated overlays do not contain resource definitions. All of the overlay resource values
     // are defined inline in the idmap.
-    overlay_assets = EmptyAssetsProvider::Create(overlay_path);
+    overlay_assets = EmptyAssetsProvider::Create(std::move(overlay_path));
   } else {
     // The overlay should be an APK.
-    overlay_assets = ZipAssetsProvider::Create(overlay_path, flags);
+    overlay_assets = ZipAssetsProvider::Create(std::move(fd), std::move(overlay_path), flags);
   }
   if (overlay_assets == nullptr) {
     return {};