1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
2 * vim: set ts=8 sts=2 et sw=2 tw=80:
3 * This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
12 #include "mozilla/MemoryReporting.h" // mozilla::MallocSizeOf
14 #include <stddef.h> // size_t
16 #include "jstypes.h" // JS_PUBLIC_API
17 #include "js/RootingAPI.h" // JS::Handle
18 #include "js/TypeDecls.h" // JSContext, JSObject, jsid, JS::Compartment, JS::GCContext, JS::Value, JS::Zone
20 // [SMDOC] Nested GC Data Structures (Compartments and Zones)
22 // The GC has two nested data structures, Zones and Compartents. Each has
23 // distint responsibilities. Zones contain compartments, along with other GC
24 // resources used by a tab. Compartments contain realms, which are specification
27 // See also the SMDoc on Realms.
31 // Security membrane; when an object from compartment A is used in compartment
32 // B, a cross-compartment wrapper (a kind of proxy) is used. In the browser,
33 // same-origin realms can share a compartment.
37 // A Zone is a group of compartments that share GC resources (arenas, strings,
38 // etc) for memory usage and performance reasons. Zone is the GC unit: the GC
39 // can operate on one or more zones at a time. The browser uses roughly one zone
42 using JSDestroyZoneCallback
= void (*)(JS::GCContext
*, JS::Zone
*);
44 using JSDestroyCompartmentCallback
= void (*)(JS::GCContext
*, JS::Compartment
*);
46 using JSSizeOfIncludingThisCompartmentCallback
=
47 size_t (*)(mozilla::MallocSizeOf
, JS::Compartment
*);
49 extern JS_PUBLIC_API
void JS_SetDestroyZoneCallback(
50 JSContext
* cx
, JSDestroyZoneCallback callback
);
52 extern JS_PUBLIC_API
void JS_SetDestroyCompartmentCallback(
53 JSContext
* cx
, JSDestroyCompartmentCallback callback
);
55 extern JS_PUBLIC_API
void JS_SetSizeOfIncludingThisCompartmentCallback(
56 JSContext
* cx
, JSSizeOfIncludingThisCompartmentCallback callback
);
58 extern JS_PUBLIC_API
void JS_SetCompartmentPrivate(JS::Compartment
* compartment
,
61 extern JS_PUBLIC_API
void* JS_GetCompartmentPrivate(
62 JS::Compartment
* compartment
);
64 extern JS_PUBLIC_API
void JS_SetZoneUserData(JS::Zone
* zone
, void* data
);
66 extern JS_PUBLIC_API
void* JS_GetZoneUserData(JS::Zone
* zone
);
68 extern JS_PUBLIC_API
bool JS_RefreshCrossCompartmentWrappers(
69 JSContext
* cx
, JS::Handle
<JSObject
*> obj
);
72 * Mark a jsid after entering a new compartment. Different zones separately
73 * mark the ids in a runtime, and this must be used any time an id is obtained
74 * from one compartment and then used in another compartment, unless the two
75 * compartments are guaranteed to be in the same zone.
77 extern JS_PUBLIC_API
void JS_MarkCrossZoneId(JSContext
* cx
, jsid id
);
80 * If value stores a jsid (an atomized string or symbol), mark that id as for
83 extern JS_PUBLIC_API
void JS_MarkCrossZoneIdValue(JSContext
* cx
,
84 const JS::Value
& value
);