Avoid internal APEX stubs in libnative{bridge,loader} and clean up

exported symbols.

The APEX stubs don't have any practical effect on the lazy loading
library wrappers. Add notes about that and update the function wrappers
to keep them in sync.

Also add tests for the lazy libraries. That necessitated some
reshuffling in libnativeloader tests to reuse the mocks.

Test: art/libnativebridge/tests/runtests.sh
Test: atest libnativebridge-lazy-tests
Test: atest libnativeloader_test libnativeloader_lazy_test
Bug: 122710865
Change-Id: I7e291f2e84d8e35731dfb1114c9b19978ff87969

libnativebridge/libnativebridge.map.txt

@@ -14,33 +14,18 @@
 # limitations under the License.
 #
 
-# TODO(b/122710865): Most of these uses come from libnativeloader, which should be bundled
-# together with libnativebridge in the APEX. Once this happens, prune this list.
+# Platform dependencies go through libnativebridge_lazy, which accesses
+# libnativebridge symbols through dlopen/dlsym. That means this list doesn't
+# have much effect, rather it's the function wrappers in native_bridge_lazy.cpp
+# that defines the exported interface. Please keep in sync with this list.
 LIBNATIVEBRIDGE_1 {
   global:
-    NativeBridgeIsSupported;
-    NativeBridgeLoadLibrary;
-    NativeBridgeUnloadLibrary;
     NativeBridgeGetError;
-    NativeBridgeIsPathSupported;
-    NativeBridgeCreateNamespace;
-    NativeBridgeGetExportedNamespace;
-    NativeBridgeLinkNamespaces;
-    NativeBridgeLoadLibraryExt;
-    NativeBridgeInitAnonymousNamespace;
     NativeBridgeInitialized;
     NativeBridgeGetTrampoline;
-    LoadNativeBridge;
     PreInitializeNativeBridge;
-    PreZygoteForkNativeBridge;
-    InitializeNativeBridge;
-    NativeBridgeGetVersion;
-    NativeBridgeGetSignalHandler;
-    UnloadNativeBridge;
     NativeBridgeAvailable;
     NeedsNativeBridge;
-    NativeBridgeError;
-    NativeBridgeNameAcceptable;
   local:
     *;
 };

libnativebridge/native_bridge_lazy.cc

@@ -44,12 +44,6 @@ FuncPtr GetFuncPtr(const char* function_name) {
 
 }  // namespace
 
-bool LoadNativeBridge(const char* native_bridge_library_filename,
-                      const struct NativeBridgeRuntimeCallbacks* runtime_callbacks) {
-  static auto f = GET_FUNC_PTR(LoadNativeBridge);
-  return f(native_bridge_library_filename, runtime_callbacks);
-}
-
 bool NeedsNativeBridge(const char* instruction_set) {
   static auto f = GET_FUNC_PTR(NeedsNativeBridge);
   return f(instruction_set);
@@ -60,21 +54,6 @@ bool PreInitializeNativeBridge(const char* app_data_dir, const char* instruction
   return f(app_data_dir, instruction_set);
 }
 
-void PreZygoteForkNativeBridge() {
-  static auto f = GET_FUNC_PTR(PreZygoteForkNativeBridge);
-  return f();
-}
-
-bool InitializeNativeBridge(JNIEnv* env, const char* instruction_set) {
-  static auto f = GET_FUNC_PTR(InitializeNativeBridge);
-  return f(env, instruction_set);
-}
-
-void UnloadNativeBridge() {
-  static auto f = GET_FUNC_PTR(UnloadNativeBridge);
-  return f();
-}
-
 bool NativeBridgeAvailable() {
   static auto f = GET_FUNC_PTR(NativeBridgeAvailable);
   return f();
@@ -85,88 +64,16 @@ bool NativeBridgeInitialized() {
   return f();
 }
 
-void* NativeBridgeLoadLibrary(const char* libpath, int flag) {
-  static auto f = GET_FUNC_PTR(NativeBridgeLoadLibrary);
-  return f(libpath, flag);
-}
-
 void* NativeBridgeGetTrampoline(void* handle, const char* name, const char* shorty, uint32_t len) {
   static auto f = GET_FUNC_PTR(NativeBridgeGetTrampoline);
   return f(handle, name, shorty, len);
 }
 
-bool NativeBridgeIsSupported(const char* libpath) {
-  static auto f = GET_FUNC_PTR(NativeBridgeIsSupported);
-  return f(libpath);
-}
-
-uint32_t NativeBridgeGetVersion() {
-  static auto f = GET_FUNC_PTR(NativeBridgeGetVersion);
-  return f();
-}
-
-NativeBridgeSignalHandlerFn NativeBridgeGetSignalHandler(int signal) {
-  static auto f = GET_FUNC_PTR(NativeBridgeGetSignalHandler);
-  return f(signal);
-}
-
-bool NativeBridgeError() {
-  static auto f = GET_FUNC_PTR(NativeBridgeError);
-  return f();
-}
-
-bool NativeBridgeNameAcceptable(const char* native_bridge_library_filename) {
-  static auto f = GET_FUNC_PTR(NativeBridgeNameAcceptable);
-  return f(native_bridge_library_filename);
-}
-
-int NativeBridgeUnloadLibrary(void* handle) {
-  static auto f = GET_FUNC_PTR(NativeBridgeUnloadLibrary);
-  return f(handle);
-}
-
 const char* NativeBridgeGetError() {
   static auto f = GET_FUNC_PTR(NativeBridgeGetError);
   return f();
 }
 
-bool NativeBridgeIsPathSupported(const char* path) {
-  static auto f = GET_FUNC_PTR(NativeBridgeIsPathSupported);
-  return f(path);
-}
-
-bool NativeBridgeInitAnonymousNamespace(const char* public_ns_sonames,
-                                        const char* anon_ns_library_path) {
-  static auto f = GET_FUNC_PTR(NativeBridgeInitAnonymousNamespace);
-  return f(public_ns_sonames, anon_ns_library_path);
-}
-
-struct native_bridge_namespace_t* NativeBridgeCreateNamespace(
-    const char* name, const char* ld_library_path, const char* default_library_path, uint64_t type,
-    const char* permitted_when_isolated_path, struct native_bridge_namespace_t* parent_ns) {
-  static auto f = GET_FUNC_PTR(NativeBridgeCreateNamespace);
-  return f(name, ld_library_path, default_library_path, type, permitted_when_isolated_path,
-           parent_ns);
-}
-
-bool NativeBridgeLinkNamespaces(struct native_bridge_namespace_t* from,
-                                struct native_bridge_namespace_t* to,
-                                const char* shared_libs_sonames) {
-  static auto f = GET_FUNC_PTR(NativeBridgeLinkNamespaces);
-  return f(from, to, shared_libs_sonames);
-}
-
-void* NativeBridgeLoadLibraryExt(const char* libpath, int flag,
-                                 struct native_bridge_namespace_t* ns) {
-  static auto f = GET_FUNC_PTR(NativeBridgeLoadLibraryExt);
-  return f(libpath, flag, ns);
-}
-
-struct native_bridge_namespace_t* NativeBridgeGetVendorNamespace() {
-  static auto f = GET_FUNC_PTR(NativeBridgeGetVendorNamespace);
-  return f();
-}
-
 #undef GET_FUNC_PTR
 
 }  // namespace android

libnativebridge/tests/Android.bp

@@ -82,7 +82,6 @@ cc_test_library {
     defaults: ["libnativebridge-test-case-defaults"],
 }
 
-// Build the unit tests.
 cc_defaults {
     name: "libnativebridge-tests-defaults",
     defaults: [
@@ -101,6 +100,11 @@ cc_defaults {
             ],
         },
     },
+}
+
+cc_test {
+    name: "libnativebridge-tests",
+    defaults: ["libnativebridge-tests-defaults"],
 
     // native_bridge.cc doesn't support reloading the native bridge after
     // unloading, so each test needs to be its own process.
@@ -132,6 +136,7 @@ cc_defaults {
 
     shared_libs: [
         "liblog",
+        "libnativebridge",
         "libnativebridge-test-case",
         "libnativebridge2-test-case",
         "libnativebridge3-test-case",
@@ -141,15 +146,14 @@ cc_defaults {
     header_libs: ["libbase_headers"],
 }
 
-cc_test {
-    name: "libnativebridge-tests",
-    defaults: ["libnativebridge-tests-defaults"],
-    shared_libs: ["libnativebridge"],
-}
-
 cc_test {
     name: "libnativebridge-lazy-tests",
     defaults: ["libnativebridge-tests-defaults"],
     host_supported: false,
-    shared_libs: ["libnativebridge_lazy"],
+    test_suites: ["device-tests"],
+    static_libs: [
+        "libbase",
+        "libnativebridge_lazy",
+    ],
+    srcs: ["libnativebridge_lazy_test.cpp"],
 }

libnativebridge/tests/libnativebridge_lazy_test.cpp

@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <android-base/macros.h>
+#include <gtest/gtest.h>
+
+#include "nativebridge/native_bridge.h"
+
+namespace android {
+
+class NativeBridgeLazyTest : public ::testing::Test {};
+
+// The testing we can do here is limited since there's no exported API to
+// actually load the native bridge, but we only need to test the trivial
+// wrappers.
+
+TEST_F(NativeBridgeLazyTest, NeedsNativeBridge) {
+  EXPECT_FALSE(NeedsNativeBridge(ABI_STRING));
+}
+
+TEST_F(NativeBridgeLazyTest, PreInitializeNativeBridge) {
+  EXPECT_FALSE(PreInitializeNativeBridge(nullptr, ""));
+}
+
+TEST_F(NativeBridgeLazyTest, NativeBridgeAvailable) {
+  EXPECT_FALSE(NativeBridgeAvailable());
+}
+
+TEST_F(NativeBridgeLazyTest, NativeBridgeInitialized) {
+  EXPECT_FALSE(NativeBridgeInitialized());
+}
+
+TEST_F(NativeBridgeLazyTest, NativeBridgeGetTrampoline) {
+  EXPECT_EQ(nullptr, NativeBridgeGetTrampoline(nullptr, nullptr, nullptr, 0));
+}
+
+TEST_F(NativeBridgeLazyTest, NativeBridgeGetError) {
+  EXPECT_STREQ("native bridge is not initialized", NativeBridgeGetError());
+}
+
+};  // namespace android

libnativeloader/Android.bp

@@ -116,21 +116,17 @@ cc_library_headers {
     export_header_lib_headers: ["jni_headers"],
 }
 
-art_cc_test {
-    name: "libnativeloader_test",
+cc_defaults {
+    name: "libnativeloader-test-defaults",
     defaults: [
         "art_module_source_build_defaults",
         "art_test_defaults",
     ],
     host_supported: false,
 
-    srcs: [
-        "native_loader_api_test.c",
-        "native_loader_test.cpp",
-    ],
     cflags: ["-DANDROID"],
 
-    // The test mocks libdl_android and libnativebridge symbols, so export them
+    // The tests mock libdl_android and libnativebridge symbols, so export them
     // to override the ones loaded from their libs.
     ldflags: [
         "-Wl,--export-dynamic-symbol=android_*",
@@ -146,8 +142,30 @@ art_cc_test {
     ],
     shared_libs: [
         "libbase",
-        "libnativeloader",
     ],
 
     test_suites: ["device-tests"],
 }
+
+art_cc_test {
+    name: "libnativeloader_test",
+    defaults: ["libnativeloader-test-defaults"],
+    srcs: [
+        "native_loader_api_test.c",
+        "native_loader_test.cpp",
+    ],
+    shared_libs: [
+        "libnativeloader",
+    ],
+}
+
+art_cc_test {
+    name: "libnativeloader_lazy_test",
+    defaults: ["libnativeloader-test-defaults"],
+    srcs: [
+        "native_loader_lazy_test.cpp",
+    ],
+    static_libs: [
+        "libnativeloader_lazy",
+    ],
+}

libnativeloader/libnativeloader.map.txt

@@ -14,12 +14,13 @@
 # limitations under the License.
 #
 
-# TODO(b/122710865): Prune these uses once the runtime APEX is complete.
+# Platform dependencies go through libnativeloader_lazy, which accesses
+# libnativeloader symbols through dlopen/dlsym. That means this list doesn't
+# have much effect, rather it's the function wrappers in native_loader_lazy.cpp
+# that defines the exported interface. Please keep in sync with this list.
 LIBNATIVELOADER_1 {
   global:
     OpenNativeLibrary;
-    InitializeNativeLoader;
-    ResetNativeLoader;
     CloseNativeLibrary;
     OpenNativeLibraryInNamespace;
     FindNamespaceByClassLoader;

libnativeloader/native_loader_lazy.cpp

@@ -44,11 +44,6 @@ FuncPtr GetFuncPtr(const char* function_name) {
 
 }  // namespace
 
-void InitializeNativeLoader() {
-  static auto f = GET_FUNC_PTR(InitializeNativeLoader);
-  return f();
-}
-
 jstring CreateClassLoaderNamespace(JNIEnv* env, int32_t target_sdk_version, jobject class_loader,
                                    bool is_shared, jstring dex_path, jstring library_path,
                                    jstring permitted_path, jstring uses_library_list) {
@@ -92,11 +87,6 @@ void* OpenNativeLibraryInNamespace(struct NativeLoaderNamespace* ns, const char*
   return f(ns, path, needs_native_bridge, error_msg);
 }
 
-void ResetNativeLoader() {
-  static auto f = GET_FUNC_PTR(ResetNativeLoader);
-  return f();
-}
-
 #undef GET_FUNC_PTR
 
 }  // namespace android