Index: ps/trunk/source/gui/Scripting/JSInterface_GUIProxy.h
===================================================================
--- ps/trunk/source/gui/Scripting/JSInterface_GUIProxy.h (revision 25252)
+++ ps/trunk/source/gui/Scripting/JSInterface_GUIProxy.h (revision 25253)
@@ -1,214 +1,215 @@
/* Copyright (C) 2021 Wildfire Games.
* This file is part of 0 A.D.
*
* 0 A.D. is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* 0 A.D. is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with 0 A.D. If not, see .
*/
#ifndef INCLUDED_JSI_GUIPROXY
#define INCLUDED_JSI_GUIPROXY
+#include "gui/ObjectBases/IGUIObject.h"
#include "scriptinterface/ScriptExtraHeaders.h"
#include
#include
class ScriptInterface;
class ScriptRequest;
template
class JSI_GUIProxy;
// See JSI_GuiProxy below
#if GCC_VERSION
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
#elif MSC_VERSION
# pragma warning(push, 1)
# pragma warning(disable: 4265)
#endif
/**
* JS GUI proxies need to store some private data.
* This class is responsible for deleting that data.
*/
class IGUIProxyObject final
{
template
friend class JSI_GUIProxy;
friend std::unique_ptr std::make_unique();
public:
JSObject* Get() const
{
return m_Object.get();
}
using PrivateData = IGUIObject*;
template
static T* FromPrivateSlot(JSObject* obj)
{
return static_cast(static_cast(js::GetProxyPrivate(obj).toPrivate()));
}
protected:
IGUIProxyObject() = default;
IGUIProxyObject(const IGUIProxyObject&) = delete;
IGUIProxyObject(IGUIProxyObject&&) = delete;
JS::PersistentRootedObject m_Object;
PrivateData m_Ptr;
};
/**
* Proxies need to store some data whose lifetime is tied to an interface.
* This is the virtual interface of that data.
*/
class GUIProxyProps
{
public:
virtual ~GUIProxyProps() {};
// @return true if @param name exists in this cache.
virtual bool has(const std::string& name) const = 0;
// @return the JSFunction matching @param name. Must call has() first as it can assume existence.
virtual JSObject* get(const std::string& name) const = 0;
virtual bool setFunction(const ScriptRequest& rq, const std::string& name, JSFunction* function) = 0;
};
/**
* Handles the js interface with C++ GUI objects.
* Proxy handlers must live for at least as long as the JS runtime
* where a proxy object with that handler was created. The reason is that
* proxy handlers are called during GC, such as on runtime destruction.
* In practical terms, this means "just keep them static and store no data".
*
* GUI Objects only exist in C++ and have no JS-only properties.
* As such, there is no "target" JS object that this proxy could point to,
* and thus we should inherit from BaseProxyHandler and not js::Wrapper.
*
* Proxies can be used with prototypes and almost treated like regular JS objects.
* However, the default implementation embarks a lot of code that we don't really need here,
* since the only fanciness is that we cache JSFunction* properties.
* As such, these GUI proxies don't have one and instead override get/set directly.
*
* To add a new JSI_GUIProxy, you'll need to:
* - overload CreateJSObject in your class header.
* - change the CGUI::AddObjectTypes method.
* - explicitly instantiate the template & CreateJSObject via DECLARE_GUIPROXY.
*
*/
template
class JSI_GUIProxy : public js::BaseProxyHandler
{
// Need to friend other specializations so CreateFunctions() can call the IGUIObject version in all codepaths.
template
friend class JSI_GUIProxy;
public:
// Access the js::Class of the Proxy.
static JSClass& ClassDefinition();
// For convenience, this is the single instantiated JSI_GUIProxy.
static JSI_GUIProxy& Singleton();
// Call this in CGUI::AddObjectTypes.
static std::pair CreateData(ScriptInterface& scriptInterface);
// Create the JS object, the proxy, the data and wrap it in a convenient unique_ptr.
static std::unique_ptr CreateJSObject(const ScriptRequest& rq, GUIObjectType* ptr, GUIProxyProps* data);
protected:
// @param family can't be nullptr because that's used for some DOM object and it crashes.
JSI_GUIProxy() : BaseProxyHandler(this, false, false) {};
// Note: SM provides no virtual destructor for baseProxyHandler.
// This also enforces making proxy handlers dataless static variables.
~JSI_GUIProxy() {};
// The default implementations need to know the type of the GUIProxyProps for this proxy type.
// This is done by specializing this struct's alias type.
struct PropCache;
// Specialize this to define the custom properties of this type.
static void CreateFunctions(const ScriptRequest& rq, GUIProxyProps* cache);
// Convenience helper for the above.
template
static void CreateFunction(const ScriptRequest& rq, GUIProxyProps* cache, const std::string& name);
// This handles returning custom properties. Specialize this if needed.
bool PropGetter(JS::HandleObject proxy, const std::string& propName, JS::MutableHandleValue vp) const;
protected:
// BaseProxyHandler interface below
// Handler for `object.x`
virtual bool get(JSContext* cx, JS::HandleObject proxy, JS::HandleValue receiver, JS::HandleId id, JS::MutableHandleValue vp) const override final;
// Handler for `object.x = y;`
virtual bool set(JSContext* cx, JS::HandleObject proxy, JS::HandleId id, JS::HandleValue vp,
JS::HandleValue receiver, JS::ObjectOpResult& result) const final;
// Handler for `delete object.x;`
virtual bool delete_(JSContext* cx, JS::HandleObject proxy, JS::HandleId id, JS::ObjectOpResult& result) const override final;
// The following methods are not provided by BaseProxyHandler.
// We provide defaults that do nothing (some raise JS exceptions).
// The JS code will see undefined when querying a property descriptor.
virtual bool getOwnPropertyDescriptor(JSContext* UNUSED(cx), JS::HandleObject UNUSED(proxy), JS::HandleId UNUSED(id),
JS::MutableHandle UNUSED(desc)) const override
{
return true;
}
// Throw an exception is JS code attempts defining a property.
virtual bool defineProperty(JSContext* UNUSED(cx), JS::HandleObject UNUSED(proxy), JS::HandleId UNUSED(id),
JS::Handle UNUSED(desc), JS::ObjectOpResult& UNUSED(result)) const override
{
return false;
}
// No accessible properties.
virtual bool ownPropertyKeys(JSContext* UNUSED(cx), JS::HandleObject UNUSED(proxy), JS::MutableHandleIdVector UNUSED(props)) const override
{
return true;
}
// Nothing to enumerate.
virtual bool enumerate(JSContext* UNUSED(cx), JS::HandleObject UNUSED(proxy), JS::MutableHandleIdVector UNUSED(props)) const override
{
return true;
}
// Throw an exception is JS attempts to query the prototype.
virtual bool getPrototypeIfOrdinary(JSContext* UNUSED(cx), JS::HandleObject UNUSED(proxy), bool* UNUSED(isOrdinary), JS::MutableHandleObject UNUSED(protop)) const override
{
return false;
}
// Throw an exception - no prototype to set.
virtual bool setImmutablePrototype(JSContext* UNUSED(cx), JS::HandleObject UNUSED(proxy), bool* UNUSED(succeeded)) const override
{
return false;
}
// We are not extensible.
virtual bool preventExtensions(JSContext* UNUSED(cx), JS::HandleObject UNUSED(proxy), JS::ObjectOpResult& UNUSED(result)) const override
{
return true;
}
virtual bool isExtensible(JSContext* UNUSED(cx), JS::HandleObject UNUSED(proxy), bool* extensible) const override
{
*extensible = false;
return true;
}
};
#if GCC_VERSION
# pragma GCC diagnostic pop
#elif MSC_VERSION
# pragma warning(pop)
#endif
#endif // INCLUDED_JSI_GUIPROXY