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/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
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* ***** BEGIN LICENSE BLOCK *****
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* Version: MPL 1.1/GPL 2.0/LGPL 2.1
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* The contents of this file are subject to the Mozilla Public License Version
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* 1.1 (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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* http://www.mozilla.org/MPL/
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* Software distributed under the License is distributed on an "AS IS" basis,
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* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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* for the specific language governing rights and limitations under the
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* The Original Code is Mozilla Communicator client code, released
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* The Initial Developer of the Original Code is
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* Netscape Communications Corporation.
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* Portions created by the Initial Developer are Copyright (C) 1998
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* the Initial Developer. All Rights Reserved.
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* Alternatively, the contents of this file may be used under the terms of
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* either of the GNU General Public License Version 2 or later (the "GPL"),
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* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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* in which case the provisions of the GPL or the LGPL are applicable instead
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* of those above. If you wish to allow use of your version of this file only
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* under the terms of either the GPL or the LGPL, and not to allow others to
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* use your version of this file under the terms of the MPL, indicate your
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* decision by deleting the provisions above and replace them with the notice
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* and other provisions required by the GPL or the LGPL. If you do not delete
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* the provisions above, a recipient may use your version of this file under
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* the terms of any one of the MPL, the GPL or the LGPL.
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* ***** END LICENSE BLOCK ***** */
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* JS object definitions.
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* A JS object consists of a possibly-shared object descriptor containing
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* ordered property names, called the map; and a dense vector of property
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* values, called slots. The map/slot pointer pair is GC'ed, while the map
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* is reference counted and the slot vector is malloc'ed.
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#include "jshash.h" /* Added by JSIFY */
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jsrefcount nrefs; /* count of all referencing objects */
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JSObjectOps *ops; /* high level object operation vtable */
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uint32 nslots; /* length of obj->slots vector */
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uint32 freeslot; /* index of next free obj->slots element */
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/* Shorthand macros for frequently-made calls. */
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#if defined JS_THREADSAFE && defined DEBUG
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#define OBJ_LOOKUP_PROPERTY(cx,obj,id,objp,propp) \
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(obj)->map->ops->lookupProperty(cx,obj,id,objp,propp,__FILE__,__LINE__)
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#define OBJ_LOOKUP_PROPERTY(cx,obj,id,objp,propp) \
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(obj)->map->ops->lookupProperty(cx,obj,id,objp,propp)
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#define OBJ_DEFINE_PROPERTY(cx,obj,id,value,getter,setter,attrs,propp) \
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(obj)->map->ops->defineProperty(cx,obj,id,value,getter,setter,attrs,propp)
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#define OBJ_GET_PROPERTY(cx,obj,id,vp) \
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(obj)->map->ops->getProperty(cx,obj,id,vp)
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#define OBJ_SET_PROPERTY(cx,obj,id,vp) \
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(obj)->map->ops->setProperty(cx,obj,id,vp)
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#define OBJ_GET_ATTRIBUTES(cx,obj,id,prop,attrsp) \
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(obj)->map->ops->getAttributes(cx,obj,id,prop,attrsp)
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#define OBJ_SET_ATTRIBUTES(cx,obj,id,prop,attrsp) \
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(obj)->map->ops->setAttributes(cx,obj,id,prop,attrsp)
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#define OBJ_DELETE_PROPERTY(cx,obj,id,rval) \
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(obj)->map->ops->deleteProperty(cx,obj,id,rval)
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#define OBJ_DEFAULT_VALUE(cx,obj,hint,vp) \
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(obj)->map->ops->defaultValue(cx,obj,hint,vp)
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#define OBJ_ENUMERATE(cx,obj,enum_op,statep,idp) \
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(obj)->map->ops->enumerate(cx,obj,enum_op,statep,idp)
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#define OBJ_CHECK_ACCESS(cx,obj,id,mode,vp,attrsp) \
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(obj)->map->ops->checkAccess(cx,obj,id,mode,vp,attrsp)
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/* These four are time-optimized to avoid stub calls. */
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#define OBJ_THIS_OBJECT(cx,obj) \
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((obj)->map->ops->thisObject \
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? (obj)->map->ops->thisObject(cx,obj) \
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#define OBJ_DROP_PROPERTY(cx,obj,prop) \
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((obj)->map->ops->dropProperty \
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? (obj)->map->ops->dropProperty(cx,obj,prop) \
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#define OBJ_GET_REQUIRED_SLOT(cx,obj,slot) \
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((obj)->map->ops->getRequiredSlot \
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? (obj)->map->ops->getRequiredSlot(cx, obj, slot) \
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#define OBJ_SET_REQUIRED_SLOT(cx,obj,slot,v) \
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((obj)->map->ops->setRequiredSlot \
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? (obj)->map->ops->setRequiredSlot(cx, obj, slot, v) \
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* In the original JS engine design, obj->slots pointed to a vector of length
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* JS_INITIAL_NSLOTS words if obj->map was shared with a prototype object,
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* else of length obj->map->nslots. With the advent of JS_GetReservedSlot,
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* JS_SetReservedSlot, and JSCLASS_HAS_RESERVED_SLOTS (see jsapi.h), the size
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* of the minimum length slots vector in the case where map is shared cannot
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* be constant. This length starts at JS_INITIAL_NSLOTS, but may advance to
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* include all the reserved slots.
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* Therefore slots must be self-describing. Rather than tag its low order bit
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* (a bit is all we need) to distinguish initial length from reserved length,
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* we do "the BSTR thing": over-allocate slots by one jsval, and store the
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* *net* length (counting usable slots, which have non-negative obj->slots[]
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* indices) in obj->slots[-1]. All code that sets obj->slots must be aware of
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* this hack -- you have been warned, and jsobj.c has been updated!
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#define JSSLOT_PROTO 0
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#define JSSLOT_PARENT 1
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#define JSSLOT_CLASS 2
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#define JSSLOT_PRIVATE 3
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#define JSSLOT_START(clasp) (((clasp)->flags & JSCLASS_HAS_PRIVATE) \
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? JSSLOT_PRIVATE + 1 \
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#define JSSLOT_FREE(clasp) (JSSLOT_START(clasp) \
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+ JSCLASS_RESERVED_SLOTS(clasp))
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#define JS_INITIAL_NSLOTS 5
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#define MAP_CHECK_SLOT(map,slot) \
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JS_ASSERT((uint32)slot < JS_MIN((map)->freeslot, (map)->nslots))
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#define OBJ_CHECK_SLOT(obj,slot) \
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MAP_CHECK_SLOT((obj)->map, slot)
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#define OBJ_CHECK_SLOT(obj,slot) ((void)0)
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/* Fast macros for accessing obj->slots while obj is locked (if thread-safe). */
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#define LOCKED_OBJ_GET_SLOT(obj,slot) \
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(OBJ_CHECK_SLOT(obj, slot), (obj)->slots[slot])
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#define LOCKED_OBJ_SET_SLOT(obj,slot,value) \
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(OBJ_CHECK_SLOT(obj, slot), (obj)->slots[slot] = (value))
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#define LOCKED_OBJ_GET_PROTO(obj) \
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JSVAL_TO_OBJECT(LOCKED_OBJ_GET_SLOT(obj, JSSLOT_PROTO))
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#define LOCKED_OBJ_GET_CLASS(obj) \
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((JSClass *)JSVAL_TO_PRIVATE(LOCKED_OBJ_GET_SLOT(obj, JSSLOT_CLASS)))
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/* Thread-safe functions and wrapper macros for accessing obj->slots. */
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#define OBJ_GET_SLOT(cx,obj,slot) \
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(OBJ_CHECK_SLOT(obj, slot), \
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(OBJ_IS_NATIVE(obj) && OBJ_SCOPE(obj)->ownercx == cx) \
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? LOCKED_OBJ_GET_SLOT(obj, slot) \
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: js_GetSlotThreadSafe(cx, obj, slot))
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#define OBJ_SET_SLOT(cx,obj,slot,value) \
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(OBJ_CHECK_SLOT(obj, slot), \
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(OBJ_IS_NATIVE(obj) && OBJ_SCOPE(obj)->ownercx == cx) \
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? (void) LOCKED_OBJ_SET_SLOT(obj, slot, value) \
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: js_SetSlotThreadSafe(cx, obj, slot, value))
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* If thread-safe, define an OBJ_GET_SLOT wrapper that bypasses, for a native
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* object, the lock-free "fast path" test of (OBJ_SCOPE(obj)->ownercx == cx),
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* to avoid needlessly switching from lock-free to lock-full scope when doing
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* GC on a different context from the last one to own the scope. The caller
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* in this case is probably a JSClass.mark function, e.g., fun_mark, or maybe
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* The GC runs only when all threads except the one on which the GC is active
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* are suspended at GC-safe points, so there is no hazard in directly accessing
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* obj->slots[slot] from the GC's thread, once rt->gcRunning has been set. See
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* jsgc.c for details.
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#define THREAD_IS_RUNNING_GC(rt, thread) \
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((rt)->gcRunning && (rt)->gcThread == (thread))
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#define CX_THREAD_IS_RUNNING_GC(cx) \
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THREAD_IS_RUNNING_GC((cx)->runtime, (cx)->thread)
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#define GC_AWARE_GET_SLOT(cx, obj, slot) \
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((OBJ_IS_NATIVE(obj) && CX_THREAD_IS_RUNNING_GC(cx)) \
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? (obj)->slots[slot] \
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: OBJ_GET_SLOT(cx, obj, slot))
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#else /* !JS_THREADSAFE */
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#define OBJ_GET_SLOT(cx,obj,slot) LOCKED_OBJ_GET_SLOT(obj,slot)
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#define OBJ_SET_SLOT(cx,obj,slot,value) LOCKED_OBJ_SET_SLOT(obj,slot,value)
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#define GC_AWARE_GET_SLOT(cx,obj,slot) LOCKED_OBJ_GET_SLOT(obj,slot)
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#endif /* !JS_THREADSAFE */
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/* Thread-safe proto, parent, and class access macros. */
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#define OBJ_GET_PROTO(cx,obj) \
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JSVAL_TO_OBJECT(OBJ_GET_SLOT(cx, obj, JSSLOT_PROTO))
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#define OBJ_SET_PROTO(cx,obj,proto) \
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OBJ_SET_SLOT(cx, obj, JSSLOT_PROTO, OBJECT_TO_JSVAL(proto))
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#define OBJ_GET_PARENT(cx,obj) \
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JSVAL_TO_OBJECT(OBJ_GET_SLOT(cx, obj, JSSLOT_PARENT))
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#define OBJ_SET_PARENT(cx,obj,parent) \
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OBJ_SET_SLOT(cx, obj, JSSLOT_PARENT, OBJECT_TO_JSVAL(parent))
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#define OBJ_GET_CLASS(cx,obj) \
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((JSClass *)JSVAL_TO_PRIVATE(OBJ_GET_SLOT(cx, obj, JSSLOT_CLASS)))
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/* Test whether a map or object is native. */
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#define MAP_IS_NATIVE(map) \
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((map)->ops == &js_ObjectOps || \
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((map)->ops && (map)->ops->newObjectMap == js_ObjectOps.newObjectMap))
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#define OBJ_IS_NATIVE(obj) MAP_IS_NATIVE((obj)->map)
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extern JS_FRIEND_DATA(JSObjectOps) js_ObjectOps;
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extern JS_FRIEND_DATA(JSObjectOps) js_WithObjectOps;
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extern JSClass js_ObjectClass;
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extern JSClass js_WithClass;
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struct JSSharpObjectMap {
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#define SHARP_BIT ((jsatomid) 1)
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#define BUSY_BIT ((jsatomid) 2)
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#define SHARP_ID_SHIFT 2
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#define IS_SHARP(he) ((jsatomid)(he)->value & SHARP_BIT)
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#define MAKE_SHARP(he) ((he)->value = (void*)((jsatomid)(he)->value|SHARP_BIT))
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#define IS_BUSY(he) ((jsatomid)(he)->value & BUSY_BIT)
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#define MAKE_BUSY(he) ((he)->value = (void*)((jsatomid)(he)->value|BUSY_BIT))
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#define CLEAR_BUSY(he) ((he)->value = (void*)((jsatomid)(he)->value&~BUSY_BIT))
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js_EnterSharpObject(JSContext *cx, JSObject *obj, JSIdArray **idap,
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js_LeaveSharpObject(JSContext *cx, JSIdArray **idap);
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js_obj_toSource(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
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js_obj_toString(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
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js_InitObjectClass(JSContext *cx, JSObject *obj);
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/* Select Object.prototype method names shared between jsapi.c and jsobj.c. */
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extern const char js_watch_str[];
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extern const char js_unwatch_str[];
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extern const char js_hasOwnProperty_str[];
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extern const char js_isPrototypeOf_str[];
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extern const char js_propertyIsEnumerable_str[];
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extern const char js_defineGetter_str[];
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extern const char js_defineSetter_str[];
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extern const char js_lookupGetter_str[];
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extern const char js_lookupSetter_str[];
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js_InitObjectMap(JSObjectMap *map, jsrefcount nrefs, JSObjectOps *ops,
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js_NewObjectMap(JSContext *cx, jsrefcount nrefs, JSObjectOps *ops,
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JSClass *clasp, JSObject *obj);
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js_DestroyObjectMap(JSContext *cx, JSObjectMap *map);
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js_HoldObjectMap(JSContext *cx, JSObjectMap *map);
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js_DropObjectMap(JSContext *cx, JSObjectMap *map, JSObject *obj);
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js_NewObject(JSContext *cx, JSClass *clasp, JSObject *proto, JSObject *parent);
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js_ConstructObject(JSContext *cx, JSClass *clasp, JSObject *proto,
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JSObject *parent, uintN argc, jsval *argv);
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js_FinalizeObject(JSContext *cx, JSObject *obj);
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js_AllocSlot(JSContext *cx, JSObject *obj, uint32 *slotp);
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js_FreeSlot(JSContext *cx, JSObject *obj, uint32 slot);
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* Find or create a property named by id in obj's scope, with the given getter
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* and setter, slot, attributes, and other members.
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extern JSScopeProperty *
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js_AddNativeProperty(JSContext *cx, JSObject *obj, jsid id,
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JSPropertyOp getter, JSPropertyOp setter, uint32 slot,
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uintN attrs, uintN flags, intN shortid);
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* Change sprop to have the given attrs, getter, and setter in scope, morphing
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* it into a potentially new JSScopeProperty. Return a pointer to the changed
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* or identical property.
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extern JSScopeProperty *
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js_ChangeNativePropertyAttrs(JSContext *cx, JSObject *obj,
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JSScopeProperty *sprop, uintN attrs, uintN mask,
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JSPropertyOp getter, JSPropertyOp setter);
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* On error, return false. On success, if propp is non-null, return true with
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* obj locked and with a held property in *propp; if propp is null, return true
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* but release obj's lock first. Therefore all callers who pass non-null propp
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* result parameters must later call OBJ_DROP_PROPERTY(cx, obj, *propp) both to
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* drop the held property, and to release the lock on obj.
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js_DefineProperty(JSContext *cx, JSObject *obj, jsid id, jsval value,
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JSPropertyOp getter, JSPropertyOp setter, uintN attrs,
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js_DefineNativeProperty(JSContext *cx, JSObject *obj, jsid id, jsval value,
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JSPropertyOp getter, JSPropertyOp setter, uintN attrs,
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uintN flags, intN shortid, JSProperty **propp);
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* Unlike js_DefineProperty, propp must be non-null. On success, and if id was
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* found, return true with *objp non-null and locked, and with a held property
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* stored in *propp. If successful but id was not found, return true with both
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* *objp and *propp null. Therefore all callers who receive a non-null *propp
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* must later call OBJ_DROP_PROPERTY(cx, *objp, *propp).
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#if defined JS_THREADSAFE && defined DEBUG
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extern JS_FRIEND_API(JSBool)
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_js_LookupProperty(JSContext *cx, JSObject *obj, jsid id, JSObject **objp,
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JSProperty **propp, const char *file, uintN line);
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#define js_LookupProperty(cx,obj,id,objp,propp) \
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_js_LookupProperty(cx,obj,id,objp,propp,__FILE__,__LINE__)
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extern JS_FRIEND_API(JSBool)
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js_LookupProperty(JSContext *cx, JSObject *obj, jsid id, JSObject **objp,
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* Specialized subroutine that allows caller to preset JSRESOLVE_* flags.
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js_LookupPropertyWithFlags(JSContext *cx, JSObject *obj, jsid id, uintN flags,
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JSObject **objp, JSProperty **propp
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#if defined JS_THREADSAFE && defined DEBUG
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, const char *file, uintN line
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extern JS_FRIEND_API(JSBool)
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js_FindProperty(JSContext *cx, jsid id, JSObject **objp, JSObject **pobjp,
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js_FindIdentifierBase(JSContext *cx, jsid id);
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js_FindVariableScope(JSContext *cx, JSFunction **funp);
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js_GetProperty(JSContext *cx, JSObject *obj, jsid id, jsval *vp);
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js_SetProperty(JSContext *cx, JSObject *obj, jsid id, jsval *vp);
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js_GetAttributes(JSContext *cx, JSObject *obj, jsid id, JSProperty *prop,
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js_SetAttributes(JSContext *cx, JSObject *obj, jsid id, JSProperty *prop,
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js_DeleteProperty(JSContext *cx, JSObject *obj, jsid id, jsval *rval);
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js_DefaultValue(JSContext *cx, JSObject *obj, JSType hint, jsval *vp);
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js_NewIdArray(JSContext *cx, jsint length);
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js_GrowIdArray(JSContext *cx, JSIdArray *ida, jsint length);
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js_Enumerate(JSContext *cx, JSObject *obj, JSIterateOp enum_op,
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jsval *statep, jsid *idp);
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js_CheckAccess(JSContext *cx, JSObject *obj, jsid id, JSAccessMode mode,
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jsval *vp, uintN *attrsp);
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js_Call(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval);
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js_Construct(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
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js_HasInstance(JSContext *cx, JSObject *obj, jsval v, JSBool *bp);
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js_SetProtoOrParent(JSContext *cx, JSObject *obj, uint32 slot, JSObject *pobj);
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js_IsDelegate(JSContext *cx, JSObject *obj, jsval v, JSBool *bp);
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js_GetClassPrototype(JSContext *cx, const char *name, JSObject **protop);
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js_SetClassPrototype(JSContext *cx, JSObject *ctor, JSObject *proto,
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js_ValueToObject(JSContext *cx, jsval v, JSObject **objp);
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js_ValueToNonNullObject(JSContext *cx, jsval v);
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js_TryValueOf(JSContext *cx, JSObject *obj, JSType type, jsval *rval);
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js_TryMethod(JSContext *cx, JSObject *obj, JSAtom *atom,
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uintN argc, jsval *argv, jsval *rval);
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js_XDRObject(JSXDRState *xdr, JSObject **objp);
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js_Mark(JSContext *cx, JSObject *obj, void *arg);
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js_Clear(JSContext *cx, JSObject *obj);
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js_GetRequiredSlot(JSContext *cx, JSObject *obj, uint32 slot);
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js_SetRequiredSlot(JSContext *cx, JSObject *obj, uint32 slot, jsval v);
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#endif /* jsobj_h___ */