diff --git a/include/nativebridge/native_bridge.h b/include/nativebridge/native_bridge.h index 523dc492a..18300bc87 100644 --- a/include/nativebridge/native_bridge.h +++ b/include/nativebridge/native_bridge.h @@ -18,6 +18,7 @@ #define NATIVE_BRIDGE_H_ #include "jni.h" +#include #include #include @@ -26,6 +27,12 @@ namespace android { struct NativeBridgeRuntimeCallbacks; struct NativeBridgeRuntimeValues; +// Function pointer type for sigaction. This is mostly the signature of a signal handler, except +// for the return type. The runtime needs to know whether the signal was handled or should be given +// to the chain. +typedef bool (*NativeBridgeSignalHandlerFn)(int, siginfo_t*, void*); + + // Open the native bridge, if any. Should be called by Runtime::Init(). A null library filename // signals that we do not want to load a native bridge. bool LoadNativeBridge(const char* native_bridge_library_filename, @@ -63,6 +70,16 @@ void* NativeBridgeGetTrampoline(void* handle, const char* name, const char* shor // True if native library is valid and is for an ABI that is supported by native bridge. bool NativeBridgeIsSupported(const char* libpath); +// Returns the version number of the native bridge. This information is available after a +// successful LoadNativeBridge() and before closing it, that is, as long as NativeBridgeAvailable() +// returns true. Returns 0 otherwise. +uint32_t NativeBridgeGetVersion(); + +// Returns a signal handler that the bridge would like to be managed. Only valid for a native +// bridge supporting the version 2 interface. Will return null if the bridge does not support +// version 2, or if it doesn't have a signal handler it wants to be known. +NativeBridgeSignalHandlerFn NativeBridgeGetSignalHandler(int signal); + // Returns whether we have seen a native bridge error. This could happen because the library // was not found, rejected, could not be initialized and so on. // @@ -127,6 +144,31 @@ struct NativeBridgeCallbacks { // NULL if not supported by native bridge. // Otherwise, return all environment values to be set after fork. const struct NativeBridgeRuntimeValues* (*getAppEnv)(const char* instruction_set); + + // Added callbacks in version 2. + + // Check whether the bridge is compatible with the given version. A bridge may decide not to be + // forwards- or backwards-compatible, and libnativebridge will then stop using it. + // + // Parameters: + // bridge_version [IN] the version of libnativebridge. + // Returns: + // true iff the native bridge supports the given version of libnativebridge. + bool (*isCompatibleWith)(uint32_t bridge_version); + + // A callback to retrieve a native bridge's signal handler for the specified signal. The runtime + // will ensure that the signal handler is being called after the runtime's own handler, but before + // all chained handlers. The native bridge should not try to install the handler by itself, as + // that will potentially lead to cycles. + // + // Parameters: + // signal [IN] the signal for which the handler is asked for. Currently, only SIGSEGV is + // supported by the runtime. + // Returns: + // NULL if the native bridge doesn't use a handler or doesn't want it to be managed by the + // runtime. + // Otherwise, a pointer to the signal handler. + NativeBridgeSignalHandlerFn (*getSignalHandler)(int signal); }; // Runtime interfaces to native bridge. diff --git a/libnativebridge/native_bridge.cc b/libnativebridge/native_bridge.cc index 6fa4b393c..f63497bd2 100644 --- a/libnativebridge/native_bridge.cc +++ b/libnativebridge/native_bridge.cc @@ -83,7 +83,7 @@ static bool had_error = false; static void* native_bridge_handle = nullptr; // Pointer to the callbacks. Available as soon as LoadNativeBridge succeeds, but only initialized // later. -static NativeBridgeCallbacks* callbacks = nullptr; +static const NativeBridgeCallbacks* callbacks = nullptr; // Callbacks provided by the environment to the bridge. Passed to LoadNativeBridge. static const NativeBridgeRuntimeCallbacks* runtime_callbacks = nullptr; @@ -96,7 +96,7 @@ static char* app_code_cache_dir = nullptr; // and hard code the directory name again here. static constexpr const char* kCodeCacheDir = "code_cache"; -static constexpr uint32_t kNativeBridgeCallbackVersion = 1; +static constexpr uint32_t kLibNativeBridgeVersion = 2; // Characters allowed in a native bridge filename. The first character must // be in [a-zA-Z] (expected 'l' for "libx"). The rest must be in [a-zA-Z0-9._-]. @@ -121,7 +121,9 @@ bool NativeBridgeNameAcceptable(const char* nb_library_filename) { // First character must be [a-zA-Z]. if (!CharacterAllowed(*ptr, true)) { // Found an invalid fist character, don't accept. - ALOGE("Native bridge library %s has been rejected for first character %c", nb_library_filename, *ptr); + ALOGE("Native bridge library %s has been rejected for first character %c", + nb_library_filename, + *ptr); return false; } else { // For the rest, be more liberal. @@ -139,8 +141,22 @@ bool NativeBridgeNameAcceptable(const char* nb_library_filename) { } } -static bool VersionCheck(NativeBridgeCallbacks* cb) { - return cb != nullptr && cb->version == kNativeBridgeCallbackVersion; +static bool VersionCheck(const NativeBridgeCallbacks* cb) { + // Libnativebridge is now designed to be forward-compatible. So only "0" is an unsupported + // version. + if (cb == nullptr || cb->version == 0) { + return false; + } + + // If this is a v2+ bridge, it may not be forwards- or backwards-compatible. Check. + if (cb->version >= 2) { + if (!callbacks->isCompatibleWith(kLibNativeBridgeVersion)) { + // TODO: Scan which version is supported, and fall back to handle it. + return false; + } + } + + return true; } static void CloseNativeBridge(bool with_error) { @@ -321,7 +337,7 @@ static void SetCpuAbi(JNIEnv* env, jclass build_class, const char* field, const } // Set up the environment for the bridged app. -static void SetupEnvironment(NativeBridgeCallbacks* callbacks, JNIEnv* env, const char* isa) { +static void SetupEnvironment(const NativeBridgeCallbacks* callbacks, JNIEnv* env, const char* isa) { // Need a JNIEnv* to do anything. if (env == nullptr) { ALOGW("No JNIEnv* to set up app environment."); @@ -485,4 +501,18 @@ bool NativeBridgeIsSupported(const char* libpath) { return false; } +uint32_t NativeBridgeGetVersion() { + if (NativeBridgeAvailable()) { + return callbacks->version; + } + return 0; +} + +NativeBridgeSignalHandlerFn NativeBridgeGetSignalHandler(int signal) { + if (NativeBridgeInitialized() && callbacks->version >= 2) { + return callbacks->getSignalHandler(signal); + } + return nullptr; +} + }; // namespace android diff --git a/libnativebridge/tests/Android.mk b/libnativebridge/tests/Android.mk index f28c4907d..285e8c242 100644 --- a/libnativebridge/tests/Android.mk +++ b/libnativebridge/tests/Android.mk @@ -11,6 +11,8 @@ test_src_files := \ CodeCacheExists_test.cpp \ CompleteFlow_test.cpp \ InvalidCharsNativeBridge_test.cpp \ + NativeBridge2Signal_test.cpp \ + NativeBridgeVersion_test.cpp \ NeedsNativeBridge_test.cpp \ PreInitializeNativeBridge_test.cpp \ PreInitializeNativeBridgeFail1_test.cpp \ diff --git a/libnativebridge/tests/Android.nativebridge-dummy.mk b/libnativebridge/tests/Android.nativebridge-dummy.mk index 1caf50afc..2efc17659 100644 --- a/libnativebridge/tests/Android.nativebridge-dummy.mk +++ b/libnativebridge/tests/Android.nativebridge-dummy.mk @@ -32,3 +32,39 @@ LOCAL_LDFLAGS := -ldl LOCAL_MULTILIB := both include $(BUILD_HOST_SHARED_LIBRARY) + + +# v2. + +NATIVE_BRIDGE2_COMMON_SRC_FILES := \ + DummyNativeBridge2.cpp + +# Shared library for target +# ======================================================== +include $(CLEAR_VARS) + +LOCAL_MODULE:= libnativebridge2-dummy + +LOCAL_SRC_FILES:= $(NATIVE_BRIDGE2_COMMON_SRC_FILES) +LOCAL_CLANG := true +LOCAL_CFLAGS += -Werror -Wall +LOCAL_CPPFLAGS := -std=gnu++11 -fvisibility=protected +LOCAL_LDFLAGS := -ldl +LOCAL_MULTILIB := both + +include $(BUILD_SHARED_LIBRARY) + +# Shared library for host +# ======================================================== +include $(CLEAR_VARS) + +LOCAL_MODULE:= libnativebridge2-dummy + +LOCAL_SRC_FILES:= $(NATIVE_BRIDGE2_COMMON_SRC_FILES) +LOCAL_CLANG := true +LOCAL_CFLAGS += -Werror -Wall +LOCAL_CPPFLAGS := -std=gnu++11 -fvisibility=protected +LOCAL_LDFLAGS := -ldl +LOCAL_MULTILIB := both + +include $(BUILD_HOST_SHARED_LIBRARY) diff --git a/libnativebridge/tests/DummyNativeBridge2.cpp b/libnativebridge/tests/DummyNativeBridge2.cpp new file mode 100644 index 000000000..6920c7482 --- /dev/null +++ b/libnativebridge/tests/DummyNativeBridge2.cpp @@ -0,0 +1,76 @@ +/* + * Copyright (C) 2014 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. + */ + +// A dummy implementation of the native-bridge interface. + +#include "nativebridge/native_bridge.h" + +#include + +// NativeBridgeCallbacks implementations +extern "C" bool native_bridge2_initialize(const android::NativeBridgeRuntimeCallbacks* /* art_cbs */, + const char* /* app_code_cache_dir */, + const char* /* isa */) { + return true; +} + +extern "C" void* native_bridge2_loadLibrary(const char* /* libpath */, int /* flag */) { + return nullptr; +} + +extern "C" void* native_bridge2_getTrampoline(void* /* handle */, const char* /* name */, + const char* /* shorty */, uint32_t /* len */) { + return nullptr; +} + +extern "C" bool native_bridge2_isSupported(const char* /* libpath */) { + return false; +} + +extern "C" const struct android::NativeBridgeRuntimeValues* native_bridge2_getAppEnv( + const char* /* abi */) { + return nullptr; +} + +extern "C" bool native_bridge2_is_compatible_compatible_with(uint32_t version) { + // For testing, allow 1 and 2, but disallow 3+. + return version <= 2; +} + +static bool native_bridge2_dummy_signal_handler(int, siginfo_t*, void*) { + // TODO: Implement something here. We'd either have to have a death test with a log here, or + // we'd have to be able to resume after the faulting instruction... + return true; +} + +extern "C" android::NativeBridgeSignalHandlerFn native_bridge2_get_signal_handler(int signal) { + if (signal == SIGSEGV) { + return &native_bridge2_dummy_signal_handler; + } + return nullptr; +} + +android::NativeBridgeCallbacks NativeBridgeItf { + .version = 2, + .initialize = &native_bridge2_initialize, + .loadLibrary = &native_bridge2_loadLibrary, + .getTrampoline = &native_bridge2_getTrampoline, + .isSupported = &native_bridge2_isSupported, + .getAppEnv = &native_bridge2_getAppEnv, + .isCompatibleWith = &native_bridge2_is_compatible_compatible_with, + .getSignalHandler = &native_bridge2_get_signal_handler +}; + diff --git a/libnativebridge/tests/NativeBridge2Signal_test.cpp b/libnativebridge/tests/NativeBridge2Signal_test.cpp new file mode 100644 index 000000000..44e45e362 --- /dev/null +++ b/libnativebridge/tests/NativeBridge2Signal_test.cpp @@ -0,0 +1,42 @@ +/* + * Copyright (C) 2014 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 "NativeBridgeTest.h" + +#include +#include + +namespace android { + +constexpr const char* kNativeBridgeLibrary2 = "libnativebridge2-dummy.so"; + +TEST_F(NativeBridgeTest, V2_Signal) { + // Init + ASSERT_TRUE(LoadNativeBridge(kNativeBridgeLibrary2, nullptr)); + ASSERT_TRUE(NativeBridgeAvailable()); + ASSERT_TRUE(PreInitializeNativeBridge(".", "isa")); + ASSERT_TRUE(NativeBridgeAvailable()); + ASSERT_TRUE(InitializeNativeBridge(nullptr, nullptr)); + ASSERT_TRUE(NativeBridgeAvailable()); + + ASSERT_EQ(2U, NativeBridgeGetVersion()); + ASSERT_NE(nullptr, NativeBridgeGetSignalHandler(SIGSEGV)); + + // Clean-up code_cache + ASSERT_EQ(0, rmdir(kCodeCache)); +} + +} // namespace android diff --git a/libnativebridge/tests/NativeBridgeVersion_test.cpp b/libnativebridge/tests/NativeBridgeVersion_test.cpp new file mode 100644 index 000000000..d3f9a80fc --- /dev/null +++ b/libnativebridge/tests/NativeBridgeVersion_test.cpp @@ -0,0 +1,38 @@ +/* + * Copyright (C) 2015 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 "NativeBridgeTest.h" + +#include + +namespace android { + +TEST_F(NativeBridgeTest, Version) { + // When a bridge isn't loaded, we expect 0. + EXPECT_EQ(NativeBridgeGetVersion(), 0U); + + // After our dummy bridge has been loaded, we expect 1. + ASSERT_TRUE(LoadNativeBridge(kNativeBridgeLibrary, nullptr)); + EXPECT_EQ(NativeBridgeGetVersion(), 1U); + + // Unload + UnloadNativeBridge(); + + // Version information is gone. + EXPECT_EQ(NativeBridgeGetVersion(), 0U); +} + +} // namespace android