/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-

 * vim: set ts=8 sts=4 et sw=4 tw=99:

 * 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/. */

#ifndef js_Realm_h

#define js_Realm_h

#include "jspubtd.h"

#include "js/GCPolicyAPI.h"

#include "js/TypeDecls.h"  // forward-declaration of JS::Realm

namespace js {

namespace gc {

JS_PUBLIC_API(void) TraceRealm(JSTracer* trc, JS::Realm* realm, const char* name);

JS_PUBLIC_API(bool) RealmNeedsSweep(JS::Realm* realm);

}

}

namespace JS {

// Each Realm holds a strong reference to its GlobalObject, and vice versa.

template <>

struct GCPolicy<Realm*> : public NonGCPointerPolicy<Realm*>

{

    static void trace(JSTracer* trc, Realm** vp, const char* name) {

        if (*vp) {

            ::js::gc::TraceRealm(trc, *vp, name);

        }

    }

    static bool needsSweep(Realm** vp) {

        return *vp && ::js::gc::RealmNeedsSweep(*vp);

    }

};

// Get the current realm, if any. The ECMAScript spec calls this "the current

// Realm Record".

extern JS_PUBLIC_API(Realm*)

GetCurrentRealmOrNull(JSContext* cx);

namespace shadow {

class Realm

{

  protected:

    JS::Compartment* compartment_;

    explicit Realm(JS::Compartment* comp)

      : compartment_(comp)

    {}

  public:

    JS::Compartment* compartment() {

        return compartment_;

    }

    static shadow::Realm* get(JS::Realm* realm) {

        return reinterpret_cast<shadow::Realm*>(realm);

    }

};

}; // namespace shadow

// Return the compartment that contains a given realm.

inline JS::Compartment*

GetCompartmentForRealm(Realm* realm)

{

    return shadow::Realm::get(realm)->compartment();

}

// Return an object's realm. All objects except cross-compartment wrappers are

// created in a particular realm, which never changes. Returns null if obj is

// a cross-compartment wrapper.

extern JS_PUBLIC_API(Realm*)

GetObjectRealmOrNull(JSObject* obj);

// Return a script's realm. All scripts are created in a particular realm, which

// never changes.

extern JS_PUBLIC_API(Realm*)

GetScriptRealm(JSScript* script);

// Get the value of the "private data" internal field of the given Realm.

// This field is initially null and is set using SetRealmPrivate.

// It's a pointer to embeddding-specific data that SpiderMonkey never uses.

extern JS_PUBLIC_API(void*)

GetRealmPrivate(Realm* realm);

// Set the "private data" internal field of the given Realm.

extern JS_PUBLIC_API(void)

SetRealmPrivate(Realm* realm, void* data);

typedef void

(* DestroyRealmCallback)(JSFreeOp* fop, Realm* realm);

// Set the callback SpiderMonkey calls just before garbage-collecting a realm.

// Embeddings can use this callback to free private data associated with the

// realm via SetRealmPrivate.

//

// By the time this is called, the global object for the realm has already been

// collected.

extern JS_PUBLIC_API(void)

SetDestroyRealmCallback(JSContext* cx, DestroyRealmCallback callback);

typedef void

(* RealmNameCallback)(JSContext* cx, Handle<Realm*> realm, char* buf, size_t bufsize);

// Set the callback SpiderMonkey calls to get the name of a realm, for

// diagnostic output.

extern JS_PUBLIC_API(void)

SetRealmNameCallback(JSContext* cx, RealmNameCallback callback);

// Get the global object for the given realm. This only returns nullptr during

// GC, between collecting the global object and destroying the Realm.

extern JS_PUBLIC_API(JSObject*)

GetRealmGlobalOrNull(Handle<Realm*> realm);

// Initialize standard JS class constructors, prototypes, and any top-level

// functions and constants associated with the standard classes (e.g. isNaN

// for Number).

extern JS_PUBLIC_API(bool)

InitRealmStandardClasses(JSContext* cx);

/*

 * Ways to get various per-Realm objects. All the getters declared below operate

 * on the JSContext's current Realm.

 */

extern JS_PUBLIC_API(JSObject*)

GetRealmObjectPrototype(JSContext* cx);

extern JS_PUBLIC_API(JSObject*)

GetRealmFunctionPrototype(JSContext* cx);

extern JS_PUBLIC_API(JSObject*)

GetRealmArrayPrototype(JSContext* cx);

extern JS_PUBLIC_API(JSObject*)

GetRealmErrorPrototype(JSContext* cx);

extern JS_PUBLIC_API(JSObject*)

GetRealmIteratorPrototype(JSContext* cx);

} // namespace JS

#endif // js_Realm_h