C++ JSValueProtect函数代码示例

	KKJSMethod::KKJSMethod(JSContextRef context, JSObjectRef jsobject, JSObjectRef thisObject) :
		context(NULL),
		jsobject(jsobject),
		thisObject(thisObject)
	{

		/* KJS methods run in the global context that they originated from
		 * this seems to prevent nasty crashes from trying to access invalid
		 * contexts later. Global contexts need to be registered by all modules
		 * that use a KJS context. */
		JSObjectRef globalObject = JSContextGetGlobalObject(context);
		JSGlobalContextRef globalContext = KJSUtil::GetGlobalContext(globalObject);

		// This context hasn't been registered. Something has gone pretty
		// terribly wrong and Kroll will likely crash soon. Nonetheless, keep
		// the user up-to-date to keep their hopes up.
		if (globalContext == NULL)
			std::cerr << "Could not locate global context for a KJS method."  <<
			             " One of the modules is misbehaving." << std::endl;

		this->context = globalContext;

		KJSUtil::ProtectGlobalContext(this->context);
		JSValueProtect(this->context, jsobject);
		if (thisObject != NULL)
			JSValueProtect(this->context, thisObject);

		this->kobject = new KKJSObject(this->context, jsobject);
	}

 EJ_BIND_FUNCTION(EJBindingCanvas,createImageData, ctx, argc, argv) {
 	if( argc < 2 ) { return NULL; }
	
 	float
 		sw = JSValueToNumberFast(ctx, argv[0]),
 		sh = JSValueToNumberFast(ctx, argv[1]);
		
 	GLubyte * pixels = (GLubyte *)calloc( sw * sh * 4, sizeof(GLubyte) );
 	EJImageData * imageData = new EJImageData(sw ,sh ,pixels);
 	imageData->autorelease();

 	// Create the JS object
 	EJBindingImageData* tempData = new EJBindingImageData();
 	JSClassRef imageDataClass = EJApp::instance()->getJSClassForClass((EJBindingBase*)tempData);
 	delete tempData;
 	JSObjectRef obj = JSObjectMake( ctx, imageDataClass, NULL );
 	JSValueProtect(ctx, obj);

 	// Create the native instance
 	EJBindingImageData * jsImageData =new EJBindingImageData(ctx,obj,imageData);

 	// Attach the native instance to the js object
 	JSObjectSetPrivate( obj, (void *)jsImageData );
 	JSValueUnprotect(ctx, obj);
 	return obj;
 }

void InspectorController::scriptObjectReady()
{
    ASSERT(m_scriptContext);
    if (!m_scriptContext)
        return;

    JSObjectRef global = JSContextGetGlobalObject(m_scriptContext);
    ASSERT(global);

    JSStringRef inspectorString = JSStringCreateWithUTF8CString("WebInspector");
    JSValueRef inspectorValue = JSObjectGetProperty(m_scriptContext, global, inspectorString, 0);
    JSStringRelease(inspectorString);

    ASSERT(inspectorValue);
    if (!inspectorValue)
        return;

    m_scriptObject = JSValueToObject(m_scriptContext, inspectorValue, 0);
    ASSERT(m_scriptObject);

    JSValueProtect(m_scriptContext, m_scriptObject);

    // Make sure our window is visible now that the page loaded
    m_client->showWindow();
}

static JSValueRef nativeFlushQueueImmediate(
    JSContextRef ctx,
    JSObjectRef function,
    JSObjectRef thisObject,
    size_t argumentCount,
    const JSValueRef arguments[],
    JSValueRef *exception) {
  if (argumentCount != 1) {
    *exception = createErrorString(ctx, "Got wrong number of args");
    return JSValueMakeUndefined(ctx);
  }

  JSCExecutor *executor;
  try {
    executor = s_globalContextRefToJSCExecutor.at(JSContextGetGlobalContext(ctx));
  } catch (std::out_of_range& e) {
    *exception = createErrorString(ctx, "Global JS context didn't map to a valid executor");
    return JSValueMakeUndefined(ctx);
  }

  JSValueProtect(ctx, arguments[0]);
  std::string resStr = Value(ctx, arguments[0]).toJSONString();

  executor->flushQueueImmediate(resStr);

  return JSValueMakeUndefined(ctx);
}

JSObjectRef 
make_object_for_class(JSContextRef ctx, int iclass, GObject *o, gboolean protect)
{
    ScriptContext *sctx = scripts_get_context();
    if (sctx == NULL) 
        return JSValueToObject(ctx, NIL, NULL);

    JSObjectRef retobj = g_object_get_qdata(o, sctx->ref_quark);
    if (retobj != NULL) {
        goto finish;
    }

    retobj = JSObjectMake(ctx, sctx->classes[iclass], o);
    if (protect) 
    {
        g_object_set_qdata_full(o, sctx->ref_quark, retobj, (GDestroyNotify)object_destroy_cb);
        JSValueProtect(ctx, retobj);
    }
    else 
        g_object_set_qdata_full(o, sctx->ref_quark, retobj, NULL);

finish:
    scripts_release_context();
    return retobj;
}

void addAccessibilityNotificationHandler(AccessibilityNotificationHandler* notificationHandler)
{
    if (!notificationHandler)
        return;

#if PLATFORM(GTK)
    JSGlobalContextRef jsContext = webkit_web_frame_get_global_context(mainFrame);
#elif PLATFORM(EFL)
    JSGlobalContextRef jsContext = DumpRenderTreeSupportEfl::globalContextRefForFrame(browser->mainFrame());
#else
    JSContextRef jsContext = 0;
#endif
    if (!jsContext)
        return;

    JSValueProtect(jsContext, notificationHandler->notificationFunctionCallback());
    // Check if this notification handler is related to a specific element.
    if (notificationHandler->platformElement()) {
        NotificationHandlersMap::iterator currentNotificationHandler = notificationHandlers.find(notificationHandler->platformElement());
        if (currentNotificationHandler != notificationHandlers.end()) {
            ASSERT(currentNotificationHandler->value->platformElement());
            JSValueUnprotect(jsContext, currentNotificationHandler->value->notificationFunctionCallback());
            notificationHandlers.remove(currentNotificationHandler->value->platformElement());
        }
        notificationHandlers.add(notificationHandler->platformElement(), notificationHandler);
    } else {
        if (globalNotificationHandler)
            JSValueUnprotect(jsContext, globalNotificationHandler->notificationFunctionCallback());
        globalNotificationHandler = notificationHandler;
    }

    connectAccessibilityCallbacks();
}

SIGNAL_CALLBACK_ID add_signal_callback(JSContextRef ctx, struct DBusObjectInfo *info,
        struct Signal *sig, JSObjectRef func)
{
    g_assert(sig != NULL);
    g_assert(func != NULL);

    if (__sig_info_hash == NULL) {
        __sig_info_hash = g_hash_table_new_full(g_str_hash, g_str_equal, NULL, (GDestroyNotify)g_hash_table_destroy);
    }
    char* key = g_strdup_printf("%s%s%s", info->path, info->iface, sig->name);

    GHashTable *cbs = g_hash_table_lookup(__sig_info_hash, key);
    if (cbs == NULL) {
	cbs = g_hash_table_new_full(g_direct_hash, g_direct_equal, NULL, (GDestroyNotify)signal_info_free);
	g_hash_table_insert(__sig_info_hash, key, cbs);
    }

    struct SignalInfo* sig_info = g_new0(struct SignalInfo, 1);
    sig_info->name = sig->name;
    sig_info->signatures = sig->signature;
    sig_info->path = info->path;
    sig_info->iface = info->iface;
    sig_info->callback = func;
    JSValueProtect(ctx, func);

    SIGNAL_CALLBACK_ID id = (SIGNAL_CALLBACK_ID)GPOINTER_TO_INT(func);
    g_hash_table_insert(cbs, GINT_TO_POINTER((int)id), sig_info);
    return id;
}

int add_signal_callback(JSContextRef ctx, struct DBusObjectInfo *info,
        struct Signal *sig, JSObjectRef func)
{
    g_assert(sig != NULL);
    g_assert(func != NULL);

    if (__sig_info_hash == NULL) {
        __sig_info_hash = g_hash_table_new_full(g_str_hash, g_str_equal, NULL, (GDestroyNotify)signal_info_free);
    }
    char* key = g_strdup_printf("%s%s%s", info->path, info->iface, sig->name);

    GSList *infos = g_hash_table_lookup(__sig_info_hash, key);
    if (infos != NULL) {
        return -1; //alerady has this callback
    }

    struct SignalInfo* sig_info = g_new0(struct SignalInfo, 1);
    sig_info->name = sig->name;
    sig_info->signatures = sig->signature;
    sig_info->path = info->path;
    sig_info->iface = info->iface;
    sig_info->callback = func;
    JSValueProtect(ctx, func);

    g_hash_table_insert(__sig_info_hash, key, sig_info);
    return GPOINTER_TO_INT(func);
}

pdf_jsimp_obj *pdf_jsimp_new_obj(pdf_jsimp *imp, pdf_jsimp_type *type, void *natobj)
{
	fz_context *ctx = imp->ctx;
	pdf_jsimp_obj *obj = fz_malloc_struct(ctx, pdf_jsimp_obj);
	priv_data *pdata = NULL;

	fz_var(pdata);
	fz_try(ctx)
	{
		pdata = fz_malloc_struct(ctx, priv_data);
		pdata->type = type;
		pdata->natobj = natobj;
		obj->ref = JSObjectMake(imp->jscore_ctx, imp->class_ref, pdata);
		if (obj->ref == NULL)
			fz_throw(ctx, FZ_ERROR_GENERIC, "JSObjectMake failed");

		JSValueProtect(imp->jscore_ctx, obj->ref);
	}
	fz_catch(ctx)
	{
		fz_free(ctx, pdata);
		fz_free(ctx, obj);
		fz_rethrow(ctx);
	}

	return obj;
}

 Closure_privateData(JSContextRef context, JSObjectRef function, const char *type) :
     cy::Functor(type, NULL),
     context_(CYGetJSContext(context)),
     function_(function)
 {
     //XXX:JSGlobalContextRetain(context_);
     JSValueProtect(context_, function_);
 }

 // For interoperability with the JavaScriptCore C API.
 JSObject::JSObject(const JSContext& js_context, JSObjectRef js_object_ref)
 : js_context__(js_context)
 , js_object_ref__(js_object_ref) {
   HAL_LOG_TRACE("JSObject:: ctor 2 ", this);
   HAL_LOG_TRACE("JSObject:: retain ", js_object_ref__, " for ", this);
   JSValueProtect(static_cast<JSContextRef>(js_context__), js_object_ref__);
   RegisterJSContext(static_cast<JSContextRef>(js_context__), js_object_ref__);
 }

JSObject& JSObject::operator=(const JSObject& other) {
  JSValueUnprotect(ctx_, instance_);
  ctx_ = other.ctx_;
  instance_ = other.instance_;
  JSValueProtect(ctx_, instance_);

  return *this;
}

jsc::Value &jsc::Value::operator = (const Value &other) {
    if (value != nullptr) {
        JSValueUnprotect(context, value);
    }
    value = other.value;
    JSValueProtect(context, value);
    return *this;
}

EJ_BIND_GET( EJBindingImageData, data, ctx ) {
	if( !dataArray ) {
		int count = m_imageData->width * m_imageData->height * 4;
		dataArray = ByteArrayToJSObject(ctx, m_imageData->pixels, count);
		JSValueProtect(ctx, dataArray);
	}
	return dataArray;
}

 CYProtect(JSContextRef context, JSObjectRef object) :
     context_(CYGetJSContext(context)),
     object_(object)
 {
     //XXX:JSGlobalContextRetain(context_);
     if (object_ != NULL)
         JSValueProtect(context_, object_);
 }