shim libraries for libnativeloader and libnativebridge

libnativeloader_lazy and libnativebridge_lazy are shim libraries for
libnativeloader and libnativebridge, respectively.

The shim libraries provides the same APIs as their counterparts, but
when the APIs are called, the APIs from the real libraries are
loaded/linked/and executed using dlopen/dlsym.

Bug: 123403798
Bug: 124250621
Test: m
Test: device boots to the UI
Test: mma under system/core/libnativebridge with aosp_cf_x86
adb sync; execute all tests under
/data/nativetest/libnativebridge-lazy-tests
All passes except NativeBridgeTest.V2_Signal which is also failing
in /data/nativetest/libnativebridge-tests.

Change-Id: Ic6484784eaa7872dcdd2decbb30943fb34c1abd7

3 files changed, 209 insertions, 15 deletions

diff --git a/libnativebridge/Android.bp b/libnativebridge/Android.bp
index c54570ee6..10d42e41f 100644
--- a/libnativebridge/Android.bp
+++ b/libnativebridge/Android.bp
@@ -1,5 +1,18 @@
+cc_defaults {
+    name: "libnativebridge-defaults",
+    cflags: [
+        "-Werror",
+        "-Wall",
+    ],
+    cppflags: [
+        "-fvisibility=protected",
+    ],
+    header_libs: ["libnativebridge-headers"],
+    export_header_lib_headers: ["libnativebridge-headers"],
+}
+
 cc_library_headers {
-    name: "libnativebridge-dummy-headers",
+    name: "libnativebridge-headers",
 
     host_supported: true,
     export_include_dirs: ["include"],
@@ -7,6 +20,7 @@ cc_library_headers {
 
 cc_library {
     name: "libnativebridge",
+    defaults: ["libnativebridge-defaults"],
 
     host_supported: true,
     srcs: ["native_bridge.cc"],
@@ -16,6 +30,8 @@ cc_library {
     shared_libs: [
         "liblog",
     ],
+    // TODO(jiyong): remove this line after aosp/885921 lands
+    export_include_dirs: ["include"],
 
     target: {
         android: {
@@ -30,16 +46,16 @@ cc_library {
         symbol_file: "libnativebridge.map.txt",
         versions: ["1"],
     },
+}
 
-    export_include_dirs: ["include"],
+// TODO(b/124250621): eliminate the need for this library
+cc_library {
+    name: "libnativebridge_lazy",
+    defaults: ["libnativebridge-defaults"],
 
-    cflags: [
-        "-Werror",
-        "-Wall",
-    ],
-    cppflags: [
-        "-fvisibility=protected",
-    ],
+    host_supported: false,
+    srcs: ["native_bridge_lazy.cc"],
+    required: ["libnativebridge"],
 }
 
 subdirs = ["tests"]
diff --git a/libnativebridge/native_bridge_lazy.cc b/libnativebridge/native_bridge_lazy.cc
new file mode 100644
index 000000000..94c80848e
--- /dev/null
+++ b/libnativebridge/native_bridge_lazy.cc
@@ -0,0 +1,167 @@
+/*
+ * Copyright (C) 2019 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 "nativebridge/native_bridge.h"
+#define LOG_TAG "nativebridge"
+
+#include <dlfcn.h>
+#include <errno.h>
+#include <string.h>
+
+#include <log/log.h>
+
+namespace android {
+
+namespace {
+
+void* GetLibHandle() {
+  static void* handle = dlopen("libnativebridge.so", RTLD_NOW);
+  LOG_FATAL_IF(handle == nullptr, "Failed to load libnativebridge.so: %s", dlerror());
+  return handle;
+}
+
+template <typename FuncPtr>
+FuncPtr GetFuncPtr(const char* function_name) {
+  auto f = reinterpret_cast<FuncPtr>(dlsym(GetLibHandle(), function_name));
+  LOG_FATAL_IF(f == nullptr, "Failed to get address of %s: %s", function_name, dlerror());
+  return f;
+}
+
+#define GET_FUNC_PTR(name) GetFuncPtr<decltype(&name)>(#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);
+}
+
+bool PreInitializeNativeBridge(const char* app_data_dir, const char* instruction_set) {
+  static auto f = GET_FUNC_PTR(PreInitializeNativeBridge);
+  return f(app_data_dir, instruction_set);
+}
+
+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();
+}
+
+bool NativeBridgeInitialized() {
+  static auto f = GET_FUNC_PTR(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
diff --git a/libnativebridge/tests/Android.bp b/libnativebridge/tests/Android.bp
index 744a4a8b8..2bb846738 100644
--- a/libnativebridge/tests/Android.bp
+++ b/libnativebridge/tests/Android.bp
@@ -23,7 +23,7 @@ cc_defaults {
         "-Wextra",
         "-Werror",
     ],
-    header_libs: ["libnativebridge-dummy-headers"],
+    header_libs: ["libnativebridge-headers"],
     cppflags: ["-fvisibility=protected"],
 }
 
@@ -46,9 +46,8 @@ cc_library_shared {
 }
 
 // Build the unit tests.
-cc_test {
-    name: "libnativebridge-tests",
-    host_supported: true,
+cc_defaults {
+    name: "libnativebridge-tests-defaults",
     test_per_src: true,
 
     cflags: [
@@ -81,12 +80,24 @@ cc_test {
 
     shared_libs: [
         "liblog",
-        "libnativebridge",
         "libnativebridge-dummy",
     ],
     header_libs: ["libbase_headers"],
 }
 
+cc_test {
+    name: "libnativebridge-tests",
+    defaults: ["libnativebridge-tests-defaults"],
+    host_supported: true,
+    shared_libs: ["libnativebridge"],
+}
+
+cc_test {
+    name: "libnativebridge-lazy-tests",
+    defaults: ["libnativebridge-tests-defaults"],
+    shared_libs: ["libnativebridge_lazy"],
+}
+
 // Build the test for the C API.
 cc_test {
     name: "libnativebridge-api-tests",
@@ -95,5 +106,5 @@ cc_test {
     srcs: [
         "NativeBridgeApi.c",
     ],
-    header_libs: ["libnativebridge-dummy-headers"],
+    header_libs: ["libnativebridge-headers"],
 }