1 /*
2 * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
14 * its contributors may be used to endorse or promote products derived
15 * from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include "config.h"
30 #include "JSPropertyNameIterator.h"
31
32 #include "JSGlobalObject.h"
33
34 namespace JSC {
35
36 ASSERT_CLASS_FITS_IN_CELL(JSPropertyNameIterator);
37
JSPropertyNameIterator(ExecState * exec,PropertyNameArrayData * propertyNameArrayData,size_t numCacheableSlots)38 inline JSPropertyNameIterator::JSPropertyNameIterator(ExecState* exec, PropertyNameArrayData* propertyNameArrayData, size_t numCacheableSlots)
39 : JSCell(exec->globalData().propertyNameIteratorStructure.get())
40 , m_cachedStructure(0)
41 , m_numCacheableSlots(numCacheableSlots)
42 , m_jsStringsSize(propertyNameArrayData->propertyNameVector().size())
43 , m_jsStrings(new JSValue[m_jsStringsSize])
44 {
45 PropertyNameArrayData::PropertyNameVector& propertyNameVector = propertyNameArrayData->propertyNameVector();
46 for (size_t i = 0; i < m_jsStringsSize; ++i)
47 m_jsStrings[i] = jsOwnedString(exec, propertyNameVector[i].ustring());
48 }
49
~JSPropertyNameIterator()50 JSPropertyNameIterator::~JSPropertyNameIterator()
51 {
52 if (m_cachedStructure)
53 m_cachedStructure->clearEnumerationCache(this);
54 }
55
create(ExecState * exec,JSObject * o)56 JSPropertyNameIterator* JSPropertyNameIterator::create(ExecState* exec, JSObject* o)
57 {
58 ASSERT(!o->structure()->enumerationCache() ||
59 o->structure()->enumerationCache()->cachedStructure() != o->structure() ||
60 o->structure()->enumerationCache()->cachedPrototypeChain() != o->structure()->prototypeChain(exec));
61
62 PropertyNameArray propertyNames(exec);
63 o->getPropertyNames(exec, propertyNames);
64 size_t numCacheableSlots = 0;
65 if (!o->structure()->hasNonEnumerableProperties() && !o->structure()->hasAnonymousSlots() &&
66 !o->structure()->hasGetterSetterProperties() && !o->structure()->isUncacheableDictionary() &&
67 !o->structure()->typeInfo().overridesGetPropertyNames())
68 numCacheableSlots = o->structure()->propertyStorageSize();
69
70 JSPropertyNameIterator* jsPropertyNameIterator = new (exec) JSPropertyNameIterator(exec, propertyNames.data(), numCacheableSlots);
71
72 if (o->structure()->isDictionary())
73 return jsPropertyNameIterator;
74
75 if (o->structure()->typeInfo().overridesGetPropertyNames())
76 return jsPropertyNameIterator;
77
78 size_t count = normalizePrototypeChain(exec, o);
79 StructureChain* structureChain = o->structure()->prototypeChain(exec);
80 RefPtr<Structure>* structure = structureChain->head();
81 for (size_t i = 0; i < count; ++i) {
82 if (structure[i]->typeInfo().overridesGetPropertyNames())
83 return jsPropertyNameIterator;
84 }
85
86 jsPropertyNameIterator->setCachedPrototypeChain(structureChain);
87 jsPropertyNameIterator->setCachedStructure(o->structure());
88 o->structure()->setEnumerationCache(jsPropertyNameIterator);
89 return jsPropertyNameIterator;
90 }
91
get(ExecState * exec,JSObject * base,size_t i)92 JSValue JSPropertyNameIterator::get(ExecState* exec, JSObject* base, size_t i)
93 {
94 JSValue& identifier = m_jsStrings[i];
95 if (m_cachedStructure == base->structure() && m_cachedPrototypeChain == base->structure()->prototypeChain(exec))
96 return identifier;
97
98 if (!base->hasProperty(exec, Identifier(exec, asString(identifier)->value(exec))))
99 return JSValue();
100 return identifier;
101 }
102
markChildren(MarkStack & markStack)103 void JSPropertyNameIterator::markChildren(MarkStack& markStack)
104 {
105 markStack.appendValues(m_jsStrings.get(), m_jsStringsSize, MayContainNullValues);
106 }
107
108 } // namespace JSC
109