Files
tubestation/widget/android/NativeJSContainer.cpp

335 lines
11 KiB
C++

/* -*- Mode: c++; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "NativeJSContainer.h"
#include "AndroidBridge.h"
#include "prthread.h"
using namespace mozilla;
using namespace mozilla::widget;
namespace mozilla {
namespace widget {
class NativeJSContainer
{
public:
static void InitJNI(JNIEnv* env) {
if (jNativeJSContainer) {
return;
}
jNativeJSContainer = AndroidBridge::GetClassGlobalRef(
env, "org/mozilla/gecko/util/NativeJSContainer");
MOZ_ASSERT(jNativeJSContainer);
jContainerNativeObject = AndroidBridge::GetFieldID(
env, jNativeJSContainer, "mNativeObject", "J");
MOZ_ASSERT(jContainerNativeObject);
jContainerConstructor = AndroidBridge::GetMethodID(
env, jNativeJSContainer, "<init>", "(J)V");
MOZ_ASSERT(jContainerConstructor);
jNativeJSObject = AndroidBridge::GetClassGlobalRef(
env, "org/mozilla/gecko/util/NativeJSObject");
MOZ_ASSERT(jNativeJSObject);
jObjectContainer = AndroidBridge::GetFieldID(
env, jNativeJSObject, "mContainer",
"Lorg/mozilla/gecko/util/NativeJSContainer;");
MOZ_ASSERT(jObjectContainer);
jObjectJSObject = AndroidBridge::GetFieldID(
env, jNativeJSObject, "mJSObject", "J");
MOZ_ASSERT(jObjectJSObject);
jObjectConstructor = AndroidBridge::GetMethodID(
env, jNativeJSObject, "<init>",
"(Lorg/mozilla/gecko/util/NativeJSObject;J)V");
MOZ_ASSERT(jContainerConstructor);
}
static jobject CreateInstance(JNIEnv* env, JSContext* cx,
JS::HandleObject object) {
return CreateInstance(env, new NativeJSContainer(cx, object));
}
static NativeJSContainer* FromInstance(JNIEnv* env, jobject instance) {
MOZ_ASSERT(instance);
const jlong fieldValue =
env->GetLongField(instance, jContainerNativeObject);
NativeJSContainer* const nativeObject =
reinterpret_cast<NativeJSContainer* const>(
static_cast<uintptr_t>(fieldValue));
if (!nativeObject) {
AndroidBridge::ThrowException(env,
"java/lang/NullPointerException",
"Uninitialized NativeJSContainer");
}
return nativeObject;
}
static void DisposeInstance(JNIEnv* env, jobject instance) {
NativeJSContainer* const container = FromInstance(env, instance);
if (container) {
env->SetLongField(instance, jContainerNativeObject,
static_cast<jlong>(reinterpret_cast<uintptr_t>(nullptr)));
delete container;
}
}
static jobject CloneInstance(JNIEnv* env, jobject instance) {
NativeJSContainer* const container = FromInstance(env, instance);
if (!container || !container->EnsureObject(env)) {
return nullptr;
}
JSContext* const cx = container->mThreadContext;
JS::RootedObject object(cx, container->mJSObject);
MOZ_ASSERT(object);
JSAutoStructuredCloneBuffer buffer;
if (!buffer.write(cx, JS::RootedValue(cx, JS::ObjectValue(*object)))) {
AndroidBridge::ThrowException(env,
"java/lang/UnsupportedOperationException",
"Cannot serialize object");
return nullptr;
}
return CreateInstance(env, new NativeJSContainer(cx, Move(buffer)));
}
static jobject GetInstanceFromObject(JNIEnv* env, jobject object) {
MOZ_ASSERT(object);
AutoLocalJNIFrame frame(env, 1);
const jobject instance = env->GetObjectField(object, jObjectContainer);
MOZ_ASSERT(instance);
return frame.Pop(instance);
}
static JSContext* GetContextFromObject(JNIEnv* env, jobject object) {
MOZ_ASSERT(object);
NativeJSContainer* const container =
FromInstance(env, GetInstanceFromObject(env, object));
if (!container) {
return nullptr;
}
return container->mThreadContext;
}
static JSObject* GetObjectFromObject(JNIEnv* env, jobject object) {
MOZ_ASSERT(object);
NativeJSContainer* const container =
FromInstance(env, GetInstanceFromObject(env, object));
if (!container ||
!container->EnsureObject(env)) { // Do thread check
return nullptr;
}
const jlong jsObject = env->GetLongField(object, jObjectJSObject);
if (!jsObject) {
// 0 for mJSObject field means it's the root object of the container
return static_cast<JSObject*>(container->mJSObject);
}
return reinterpret_cast<JSObject*>(static_cast<uintptr_t>(jsObject));
}
// Make sure we have a JSObject and deserialize if necessary/possible
bool EnsureObject(JNIEnv* env) {
if (mJSObject) {
if (PR_GetCurrentThread() != mThread) {
AndroidBridge::ThrowException(env,
"java/lang/IllegalThreadStateException",
"Using NativeJSObject off its thread");
return false;
}
return true;
}
if (!SwitchContextToCurrentThread()) {
AndroidBridge::ThrowException(env,
"java/lang/IllegalThreadStateException",
"Not available for this thread");
return false;
}
JS::RootedValue value(mThreadContext);
MOZ_ASSERT(mBuffer.data());
MOZ_ALWAYS_TRUE(mBuffer.read(mThreadContext, &value));
if (value.isObject()) {
mJSObject = &value.toObject();
}
if (!mJSObject) {
AndroidBridge::ThrowException(env,
"java/lang/IllegalStateException", "Cannot deserialize data");
return false;
}
mBuffer.clear();
return true;
}
private:
static jclass jNativeJSContainer;
static jfieldID jContainerNativeObject;
static jmethodID jContainerConstructor;
static jclass jNativeJSObject;
static jfieldID jObjectContainer;
static jfieldID jObjectJSObject;
static jmethodID jObjectConstructor;
static jobject CreateInstance(JNIEnv* env,
NativeJSContainer* nativeObject) {
InitJNI(env);
const jobject newObject =
env->NewObject(jNativeJSContainer, jContainerConstructor,
static_cast<jlong>(
reinterpret_cast<uintptr_t>(nativeObject)));
AndroidBridge::HandleUncaughtException(env);
MOZ_ASSERT(newObject);
return newObject;
}
// Thread that the object is valid on
PRThread* mThread;
// Context that the object is valid in
JSContext* mThreadContext;
// Deserialized object, or nullptr if object is in serialized form
JS::Heap<JSObject*> mJSObject;
// Serialized object, or empty if object is in deserialized form
JSAutoStructuredCloneBuffer mBuffer;
// Create a new container containing the given deserialized object
NativeJSContainer(JSContext* cx, JS::HandleObject object)
: mThread(PR_GetCurrentThread())
, mThreadContext(cx)
, mJSObject(object)
{
}
// Create a new container containing the given serialized object
NativeJSContainer(JSContext* cx, JSAutoStructuredCloneBuffer&& buffer)
: mThread(PR_GetCurrentThread())
, mThreadContext(cx)
, mBuffer(Forward<JSAutoStructuredCloneBuffer>(buffer))
{
}
bool SwitchContextToCurrentThread() {
PRThread* const currentThread = PR_GetCurrentThread();
if (currentThread == mThread) {
return true;
}
return false;
}
};
jclass NativeJSContainer::jNativeJSContainer = 0;
jfieldID NativeJSContainer::jContainerNativeObject = 0;
jmethodID NativeJSContainer::jContainerConstructor = 0;
jclass NativeJSContainer::jNativeJSObject = 0;
jfieldID NativeJSContainer::jObjectContainer = 0;
jfieldID NativeJSContainer::jObjectJSObject = 0;
jmethodID NativeJSContainer::jObjectConstructor = 0;
jobject
CreateNativeJSContainer(JNIEnv* env, JSContext* cx, JS::HandleObject object)
{
return NativeJSContainer::CreateInstance(env, cx, object);
}
} // namespace widget
} // namespace mozilla
namespace {
class JSJNIString
{
public:
JSJNIString(JNIEnv* env, jstring str)
: mEnv(env)
, mJNIString(str)
, mJSString(!str ? nullptr :
reinterpret_cast<const jschar*>(env->GetStringChars(str, nullptr)))
{
}
~JSJNIString() {
if (mJNIString) {
mEnv->ReleaseStringChars(mJNIString,
reinterpret_cast<const jchar*>(mJSString));
}
}
operator const jschar*() const {
return mJSString;
}
size_t Length() const {
return static_cast<size_t>(mEnv->GetStringLength(mJNIString));
}
private:
JNIEnv* const mEnv;
const jstring mJNIString;
const jschar* const mJSString;
};
bool
CheckJSCall(JNIEnv* env, bool result) {
if (!result) {
AndroidBridge::ThrowException(env,
"java/lang/UnsupportedOperationException", "JSAPI call failed");
}
return result;
}
bool
CheckJNIArgument(JNIEnv* env, jobject arg) {
if (!arg) {
AndroidBridge::ThrowException(env,
"java/lang/IllegalArgumentException", "Null argument");
return false;
}
return true;
}
bool
AppendJSON(const jschar* buf, uint32_t len, void* data)
{
static_cast<nsAutoString*>(data)->Append(buf, len);
return true;
}
} // namespace
extern "C" {
NS_EXPORT void JNICALL
Java_org_mozilla_gecko_util_NativeJSContainer_dispose(JNIEnv* env, jobject instance)
{
MOZ_ASSERT(env);
NativeJSContainer::DisposeInstance(env, instance);
}
NS_EXPORT jobject JNICALL
Java_org_mozilla_gecko_util_NativeJSContainer_clone(JNIEnv* env, jobject instance)
{
MOZ_ASSERT(env);
return NativeJSContainer::CloneInstance(env, instance);
}
NS_EXPORT jstring JNICALL
Java_org_mozilla_gecko_util_NativeJSObject_toString(JNIEnv* env, jobject instance)
{
MOZ_ASSERT(env);
MOZ_ASSERT(instance);
JSContext* const cx = NativeJSContainer::GetContextFromObject(env, instance);
const JS::RootedObject object(cx, NativeJSContainer::GetObjectFromObject(env, instance));
JS::RootedValue value(cx, JS::ObjectValue(*object));
nsAutoString json;
if (!object ||
!CheckJSCall(env,
JS_Stringify(cx, &value, JS::NullPtr(), JS::NullHandleValue, AppendJSON, &json))) {
return nullptr;
}
jstring ret = env->NewString(reinterpret_cast<const jchar*>(json.get()), json.Length());
AndroidBridge::HandleUncaughtException(env);
MOZ_ASSERT(ret);
return ret;
}
} // extern "C"