dom/bindings/JSSlots.h

   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 file,
   5  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 /**
   8  * This file defines various reserved slot indices used by JavaScript
   9  * reflections of DOM objects.
  10  */
  11 #ifndef mozilla_dom_DOMSlots_h
  12 #define mozilla_dom_DOMSlots_h
  13
  14 // We use slot 0 for holding the raw object.  This is safe for both
  15 // globals and non-globals.
  16 // NOTE: This is baked into the Ion JIT as 0 in codegen for LGetDOMProperty and
  17 // LSetDOMProperty. Those constants need to be changed accordingly if this value
  18 // changes.
  19 #define DOM_OBJECT_SLOT 0
  20
  21 // The total number of slots non-proxy DOM objects use by default.
  22 // Specific objects may have more for storing cached values.
  23 #define DOM_INSTANCE_RESERVED_SLOTS 1
  24
  25 // Interface objects store a number of reserved slots equal to
  26 // INTERFACE_OBJECT_INFO_RESERVED_SLOT + number of legacy factory functions,
  27 // with a maximum of js::FunctionExtended::NUM_EXTENDED_SLOTS.
  28 // INTERFACE_OBJECT_INFO_RESERVED_SLOT contains the DOMInterfaceInfo.
  29 // INTERFACE_OBJECT_FIRST_LEGACY_FACTORY_FUNCTION and higher contain the
  30 // JSObjects for the legacy factory functions.
  31 enum {
  32   INTERFACE_OBJECT_INFO_RESERVED_SLOT = 0,
  33   INTERFACE_OBJECT_FIRST_LEGACY_FACTORY_FUNCTION,
  34 };
  35 // See js::FunctionExtended::NUM_EXTENDED_SLOTS.
  36 #define INTERFACE_OBJECT_MAX_SLOTS 3
  37
  38 // Legacy factory functions store a JSNativeHolder in the
  39 // LEGACY_FACTORY_FUNCTION_NATIVE_HOLDER_RESERVED_SLOT slot.
  40 enum { LEGACY_FACTORY_FUNCTION_NATIVE_HOLDER_RESERVED_SLOT = 0 };
  41
  42 // Interface prototype objects store a number of reserved slots equal to
  43 // DOM_INTERFACE_PROTO_SLOTS_BASE or DOM_INTERFACE_PROTO_SLOTS_BASE + 1 if a
  44 // slot for the unforgeable holder is needed.
  45 #define DOM_INTERFACE_PROTO_SLOTS_BASE 0
  46
  47 // The slot index of raw pointer of dom object stored in observable array exotic
  48 // object. We need this in order to call the OnSet* and OnDelete* callbacks.
  49 #define OBSERVABLE_ARRAY_DOM_INTERFACE_SLOT 0
  50
  51 // The slot index of backing list stored in observable array exotic object.
  52 #define OBSERVABLE_ARRAY_BACKING_LIST_OBJECT_SLOT 1
  53
  54 #endif /* mozilla_dom_DOMSlots_h */