jni_jsobject.mm

linux下开源浏览器WebKit的源码,市面上的很多商用浏览器都是移植自WebKit

/*
 * Copyright (C) 2003, 2008 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
 */

#include "config.h"
#include "jni_jsobject.h"

#if ENABLE(MAC_JAVA_BRIDGE)

#include "Frame.h"
#include "WebCoreFrameView.h"
#include "jni_runtime.h"
#include "jni_utility.h"
#include "ScriptController.h"
#include "runtime_object.h"
#include "runtime_root.h"
#include <interpreter/CallFrame.h>
#include <runtime/JSGlobalObject.h>
#include <runtime/JSLock.h>
#include <runtime/Completion.h>
#include <runtime/Completion.h>
#include <wtf/Assertions.h>
#include <parser/SourceProvider.h>

using WebCore::Frame;

using namespace JSC::Bindings;
using namespace JSC;

#ifdef NDEBUG
#define JS_LOG(formatAndArgs...) ((void)0)
#else
#define JS_LOG(formatAndArgs...) { \
    fprintf (stderr, "%s(%p,%p):  ", __PRETTY_FUNCTION__, _performJavaScriptRunLoop, CFRunLoopGetCurrent()); \
    fprintf(stderr, formatAndArgs); \
}
#endif

#define UndefinedHandle 1

static CFRunLoopSourceRef _performJavaScriptSource;
static CFRunLoopRef _performJavaScriptRunLoop;

// May only be set by dispatchToJavaScriptThread().
static CFRunLoopSourceRef completionSource;

static void completedJavaScriptAccess (void *i)
{
    assert (CFRunLoopGetCurrent() != _performJavaScriptRunLoop);
    
    JSObjectCallContext *callContext = (JSObjectCallContext *)i;
    CFRunLoopRef runLoop = (CFRunLoopRef)callContext->originatingLoop;
    
    assert (CFRunLoopGetCurrent() == runLoop);
    
    CFRunLoopStop(runLoop);
}

static pthread_once_t javaScriptAccessLockOnce = PTHREAD_ONCE_INIT;
static pthread_mutex_t javaScriptAccessLock;
static int javaScriptAccessLockCount = 0;

static void initializeJavaScriptAccessLock()
{
    pthread_mutexattr_t attr;
    
    pthread_mutexattr_init(&attr);
    pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_RECURSIVE);
    
    pthread_mutex_init(&javaScriptAccessLock, &attr);
}

static inline void lockJavaScriptAccess()
{
    // Perhaps add deadlock detection?
    pthread_once(&javaScriptAccessLockOnce, initializeJavaScriptAccessLock);
    pthread_mutex_lock(&javaScriptAccessLock);
    javaScriptAccessLockCount++;
}

static inline void unlockJavaScriptAccess()
{
    javaScriptAccessLockCount--;
    pthread_mutex_unlock(&javaScriptAccessLock);
}

static void dispatchToJavaScriptThread(JSObjectCallContext *context)
{
    // This lock guarantees that only one thread can invoke
    // at a time, and also guarantees that completionSource;
    // won't get clobbered.
    lockJavaScriptAccess();
    
    CFRunLoopRef currentRunLoop = CFRunLoopGetCurrent();
    
    assert (currentRunLoop != _performJavaScriptRunLoop);
    
    // Setup a source to signal once the invocation of the JavaScript
    // call completes.
    //
    // FIXME:  This could be a potential performance issue.  Creating and
    // adding run loop sources is expensive.  We could create one source 
    // per thread, as needed, instead.
    context->originatingLoop = currentRunLoop;
    CFRunLoopSourceContext sourceContext = {0, context, NULL, NULL, NULL, NULL, NULL, NULL, NULL, completedJavaScriptAccess};
    completionSource = CFRunLoopSourceCreate(NULL, 0, &sourceContext);
    CFRunLoopAddSource(currentRunLoop, completionSource, kCFRunLoopDefaultMode);
    
    // Wakeup JavaScript access thread and make it do it's work.
    CFRunLoopSourceSignal(_performJavaScriptSource);
    if (CFRunLoopIsWaiting(_performJavaScriptRunLoop))
        CFRunLoopWakeUp(_performJavaScriptRunLoop);
    
    // Wait until the JavaScript access thread is done.
    CFRunLoopRun ();
    
    CFRunLoopRemoveSource(currentRunLoop, completionSource, kCFRunLoopDefaultMode);
    CFRelease (completionSource);
    
    unlockJavaScriptAccess();
}

static void performJavaScriptAccess(void*)
{
    assert (CFRunLoopGetCurrent() == _performJavaScriptRunLoop);
    
    // Dispatch JavaScript calls here.
    CFRunLoopSourceContext sourceContext;
    CFRunLoopSourceGetContext (completionSource, &sourceContext);
    JSObjectCallContext *callContext = (JSObjectCallContext *)sourceContext.info;    
    CFRunLoopRef originatingLoop = callContext->originatingLoop;
    
    JavaJSObject::invoke (callContext);
    
    // Signal the originating thread that we're done.
    CFRunLoopSourceSignal (completionSource);
    if (CFRunLoopIsWaiting(originatingLoop))
        CFRunLoopWakeUp(originatingLoop);
}

// Must be called from the thread that will be used to access JavaScript.
void JavaJSObject::initializeJNIThreading() {
    // Should only be called once.
    ASSERT(!_performJavaScriptRunLoop);
    
    // Assume that we can retain this run loop forever.  It'll most 
    // likely (always?) be the main loop.
    _performJavaScriptRunLoop = (CFRunLoopRef)CFRetain(CFRunLoopGetCurrent());
    
    // Setup a source the other threads can use to signal the _runLoop
    // thread that a JavaScript call needs to be invoked.
    CFRunLoopSourceContext sourceContext = {0, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, performJavaScriptAccess};
    _performJavaScriptSource = CFRunLoopSourceCreate(NULL, 0, &sourceContext);
    CFRunLoopAddSource(_performJavaScriptRunLoop, _performJavaScriptSource, kCFRunLoopDefaultMode);
}

static bool isJavaScriptThread()
{
    return (_performJavaScriptRunLoop == CFRunLoopGetCurrent());
}

jvalue JavaJSObject::invoke(JSObjectCallContext *context)
{
    jvalue result;

    bzero ((void *)&result, sizeof(jvalue));
    
    if (!isJavaScriptThread()) {        
        // Send the call context to the thread that is allowed to
        // call JavaScript.
        dispatchToJavaScriptThread(context);
        result = context->result;
    }
    else {
        jlong nativeHandle = context->nativeHandle;
        if (nativeHandle == UndefinedHandle || nativeHandle == 0) {
            return result;
        }

        if (context->type == CreateNative) {
            result.j = JavaJSObject::createNative(nativeHandle);
        }
        else {
            JSObject *imp = jlong_to_impptr(nativeHandle);
            if (!findProtectingRootObject(imp)) {
                fprintf (stderr, "%s:%d:  Attempt to access JavaScript from destroyed applet, type %d.\n", __FILE__, __LINE__, context->type);
                return result;
            }

            switch (context->type){            
                case Call: {
                    result.l = JavaJSObject(nativeHandle).call(context->string, context->args);
                    break;
                }
                
                case Eval: {
                    result.l = JavaJSObject(nativeHandle).eval(context->string);
                    break;
                }
            
                case GetMember: {
                    result.l = JavaJSObject(nativeHandle).getMember(context->string);
                    break;
                }
                
                case SetMember: {
                    JavaJSObject(nativeHandle).setMember(context->string, context->value);
                    break;
                }
                
                case RemoveMember: {
                    JavaJSObject(nativeHandle).removeMember(context->string);
                    break;
                }
            
                case GetSlot: {
                    result.l = JavaJSObject(nativeHandle).getSlot(context->index);
                    break;
                }
                
                case SetSlot: {
                    JavaJSObject(nativeHandle).setSlot(context->index, context->value);
                    break;
                }
            
                case ToString: {
                    result.l = (jobject) JavaJSObject(nativeHandle).toString();
                    break;
                }
    
                case Finalize: {
                    JavaJSObject(nativeHandle).finalize();
                    break;
                }
                
                default: {
                    fprintf (stderr, "%s:  invalid JavaScript call\n", __PRETTY_FUNCTION__);
                }
            }
        }
        context->result = result;
    }

    return result;
}


JavaJSObject::JavaJSObject(jlong nativeJSObject)
{
    _imp = jlong_to_impptr(nativeJSObject);
    
    ASSERT(_imp);
    _rootObject = findProtectingRootObject(_imp);
    ASSERT(_rootObject);
}

RootObject* JavaJSObject::rootObject() const
{ 
    return _rootObject && _rootObject->isValid() ? _rootObject.get() : 0; 
}

jobject JavaJSObject::call(jstring methodName, jobjectArray args) const
{
    JS_LOG ("methodName = %s\n", JavaString(methodName).UTF8String());

    RootObject* rootObject = this->rootObject();
    if (!rootObject)
        return 0;
    
    // Lookup the function object.
    ExecState* exec = rootObject->globalObject()->globalExec();
    JSLock lock(false);
    
    Identifier identifier(exec, JavaString(methodName));
    JSValuePtr function = _imp->get(exec, identifier);
    CallData callData;
    CallType callType = function.getCallData(callData);
    if (callType == CallTypeNone)
        return 0;

    // Call the function object.
    ArgList argList;
    getListFromJArray(exec, args, argList);
    rootObject->globalObject()->globalData()->timeoutChecker.start();
    JSValuePtr result = JSC::call(exec, function, callType, callData, _imp, argList);
    rootObject->globalObject()->globalData()->timeoutChecker.stop();

    return convertValueToJObject(result);
}

jobject JavaJSObject::eval(jstring script) const
{
    JS_LOG ("script = %s\n", JavaString(script).UTF8String());
    
    JSValuePtr result;

    JSLock lock(false);
    
    RootObject* rootObject = this->rootObject();
    if (!rootObject)
        return 0;

    rootObject->globalObject()->globalData()->timeoutChecker.start();
    Completion completion = JSC::evaluate(rootObject->globalObject()->globalExec(), rootObject->globalObject()->globalScopeChain(), makeSource(JavaString(script)));
    rootObject->globalObject()->globalData()->timeoutChecker.stop();
    ComplType type = completion.complType();
    
    if (type == Normal) {
        result = completion.value();
        if (!result)
            result = jsUndefined();
    } else
        result = jsUndefined();
    
    return convertValueToJObject (result);
}

jobject JavaJSObject::getMember(jstring memberName) const
{
    JS_LOG ("(%p) memberName = %s\n", _imp, JavaString(memberName).UTF8String());

    RootObject* rootObject = this->rootObject();
    if (!rootObject)
        return 0;

    ExecState* exec = rootObject->globalObject()->globalExec();
    
    JSLock lock(false);
    JSValuePtr result = _imp->get(exec, Identifier(exec, JavaString(memberName)));

    return convertValueToJObject(result);
}

void JavaJSObject::setMember(jstring memberName, jobject value) const
{
    JS_LOG ("memberName = %s, value = %p\n", JavaString(memberName).UTF8String(), value);

    RootObject* rootObject = this->rootObject();
    if (!rootObject)
        return;