Make NativeLoaderNamespace instances immutable.

To make it easier to reason about thread safety.

Test: atest libnativeloader_e2e_tests libnativeloader_test \
            art_libnativeloader_cts_test libnativeloader_lazy_test
Bug: 326505705
Bug: 326610154
Change-Id: I2447ed8120625823d3298d392d22828af2c22402

3 files changed, 14 insertions, 11 deletions

diff --git a/libnativeloader/library_namespaces.cpp b/libnativeloader/library_namespaces.cpp
index 7aa14080ce..b27b268d16 100644
--- a/libnativeloader/library_namespaces.cpp
+++ b/libnativeloader/library_namespaces.cpp
@@ -432,10 +432,10 @@ Result<NativeLoaderNamespace*> LibraryNamespaces::Create(JNIEnv* env,
   const std::string product_libs =
       filter_public_libraries(target_sdk_version, uses_libraries, product_public_libraries());
   if (!product_libs.empty()) {
-    Result<NativeLoaderNamespace> target_ns = system_ns;
-    if (is_product_treblelized()) {
-      target_ns = NativeLoaderNamespace::GetExportedNamespace(kProductNamespaceName, is_bridged);
-    }
+    Result<NativeLoaderNamespace> target_ns =
+        is_product_treblelized()
+            ? NativeLoaderNamespace::GetExportedNamespace(kProductNamespaceName, is_bridged)
+            : system_ns;
     if (target_ns.ok()) {
       linked = app_ns->Link(&target_ns.value(), product_libs);
       if (!linked.ok()) {
diff --git a/libnativeloader/native_loader_namespace.cpp b/libnativeloader/native_loader_namespace.cpp
index cfb84b7d9e..98236064d0 100644
--- a/libnativeloader/native_loader_namespace.cpp
+++ b/libnativeloader/native_loader_namespace.cpp
@@ -69,10 +69,14 @@ Result<NativeLoaderNamespace> NativeLoaderNamespace::GetExportedNamespace(const
 // "system" for those in the Runtime APEX. Try "system" first since
 // "default" always exists.
 Result<NativeLoaderNamespace> NativeLoaderNamespace::GetSystemNamespace(bool is_bridged) {
-  Result<NativeLoaderNamespace> ns = GetExportedNamespace(kSystemNamespaceName, is_bridged);
-  if (ns.ok()) return ns;
-  ns = GetExportedNamespace(kDefaultNamespaceName, is_bridged);
-  if (ns.ok()) return ns;
+  if (Result<NativeLoaderNamespace> ns = GetExportedNamespace(kSystemNamespaceName, is_bridged);
+      ns.ok()) {
+    return ns;
+  }
+  if (Result<NativeLoaderNamespace> ns = GetExportedNamespace(kDefaultNamespaceName, is_bridged);
+      ns.ok()) {
+    return ns;
+  }
 
   // If nothing is found, return NativeLoaderNamespace constructed from nullptr.
   // nullptr also means default namespace to the linker.
diff --git a/libnativeloader/native_loader_namespace.h b/libnativeloader/native_loader_namespace.h
index 9a5aeac203..4d9ce36434 100644
--- a/libnativeloader/native_loader_namespace.h
+++ b/libnativeloader/native_loader_namespace.h
@@ -47,7 +47,6 @@ struct NativeLoaderNamespace {
 
   NativeLoaderNamespace(NativeLoaderNamespace&&) = default;
   NativeLoaderNamespace(const NativeLoaderNamespace&) = default;
-  NativeLoaderNamespace& operator=(const NativeLoaderNamespace&) = default;
 
   android_namespace_t* ToRawAndroidNamespace() const { return std::get<0>(raw_); }
   native_bridge_namespace_t* ToRawNativeBridgeNamespace() const { return std::get<1>(raw_); }
@@ -72,8 +71,8 @@ struct NativeLoaderNamespace {
   explicit NativeLoaderNamespace(const std::string& name, native_bridge_namespace_t* ns)
       : name_(name), raw_(ns) {}
 
-  std::string name_;
-  std::variant<android_namespace_t*, native_bridge_namespace_t*> raw_;
+  const std::string name_;
+  const std::variant<android_namespace_t*, native_bridge_namespace_t*> raw_;
 };
 
 }  // namespace android