Merge "AndroidRuntime: Expose javaAttachThread / javaDetachThread." (6b45a9a7) · Commits · e / os / android_frameworks_base

core/jni/Android.bp

+16 −0

Original line number	Diff line number	Diff line
		@@ -297,6 +297,7 @@ cc_library_shared {
		header_libs: [
		"bionic_libc_platform_headers",
		"dnsproxyd_protocol_headers",
		"libandroid_runtime_threads_headers",
		],
		},
		host: {
		@@ -338,3 +339,18 @@ cc_library_shared {
		never: true,
		},
		}

		cc_library_headers {
		name: "libandroid_runtime_threads_headers",
		host_supported: true,
		vendor_available: true,
		// TODO(b/153609531): remove when libbinder is not native_bridge_supported
		native_bridge_supported: true,
		// Allow only modules from the following list to create threads that can be
		// attached to the JVM. This list should be a subset of the dependencies of
		// libandroid_runtime.
		visibility: [
		"//frameworks/native/libs/binder",
		],
		export_include_dirs: ["include_threads"],
		}

core/jni/AndroidRuntime.cpp

+15 −15

Original line number	Diff line number	Diff line
		@@ -22,6 +22,7 @@
		#include <android-base/properties.h>
		#include <android/graphics/jni_runtime.h>
		#include <android_runtime/AndroidRuntime.h>
		#include <android_runtime/threads.h>
		#include <assert.h>
		#include <binder/IBinder.h>
		#include <binder/IPCThreadState.h>
		@@ -1338,14 +1339,15 @@ void AndroidRuntime::onVmCreated(JNIEnv* env)
		return env;
		}

		extern "C" {

		/*
		* Makes the current thread visible to the VM.
		*
		* The JNIEnv pointer returned is only valid for the current thread, and
		* thus must be tucked into thread-local storage.
		*/
		static int javaAttachThread(const char* threadName, JNIEnv** pEnv)
		{
		bool androidJavaAttachThread(const char* threadName) {
		JavaVMAttachArgs args;
		JavaVM* vm;
		jint result;
		@@ -1357,18 +1359,17 @@ static int javaAttachThread(const char* threadName, JNIEnv** pEnv)
		args.name = (char*) threadName;
		args.group = NULL;

		result = vm->AttachCurrentThread(pEnv, (void*) &args);
		if (result != JNI_OK)
		ALOGI("NOTE: attach of thread '%s' failed\n", threadName);
		JNIEnv* env;
		result = vm->AttachCurrentThread(&env, (void*)&args);
		if (result != JNI_OK) ALOGI("NOTE: attach of thread '%s' failed\n", threadName);

		return result;
		return result == JNI_OK;
		}

		/*
		* Detach the current thread from the set visible to the VM.
		*/
		static int javaDetachThread(void)
		{
		bool androidJavaDetachThread(void) {
		JavaVM* vm;
		jint result;

		@@ -1376,11 +1377,12 @@ static int javaDetachThread(void)
		assert(vm != NULL);

		result = vm->DetachCurrentThread();
		if (result != JNI_OK)
		ALOGE("ERROR: thread detach failed\n");
		return result;
		if (result != JNI_OK) ALOGE("ERROR: thread detach failed\n");
		return result == JNI_OK;
		}

		} // extern "C"

		/*
		* When starting a native thread that will be visible from the VM, we
		* bounce through this to get the right attach/detach action.
		@@ -1391,18 +1393,16 @@ static int javaDetachThread(void)
		void* userData = ((void **)args)[1];
		char* name = (char) ((void *)args)[2]; // we own this storage
		free(args);
		JNIEnv* env;
		int result;

		/* hook us into the VM */
		if (javaAttachThread(name, &env) != JNI_OK)
		return -1;
		if (!androidJavaAttachThread(name)) return -1;

		/* start the thread running */
		result = (*(android_thread_func_t)start)(userData);

		/* unhook us */
		javaDetachThread();
		(void)androidJavaDetachThread();
		free(name);

		return result;

core/jni/include_threads/android_runtime/threads.h

0 → 100644

+30 −0

Original line number	Diff line number	Diff line
		/*
		* 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.
		*/

		// Manages the interaction between threads and the Android Runtime. If these symbols do not exist
		// at runtime, it means the current process does not link to libandroid_runtime.

		#pragma once

		extern "C" {

		// Attach current thread to JVM. Return true if successful, false otherwise.
		bool androidJavaAttachThread(const char* threadName);

		// Detach current thread to JVM. Return true if successful, false otherwise.
		bool androidJavaDetachThread();

		} // extern "C"