1 /* 2 * Copyright (C) 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 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 27 #include "config.h" 28 29 #include "PropertyDescriptor.h" 30 31 #include "GetterSetter.h" 32 #include "JSObject.h" 33 #include "Operations.h" 34 35 namespace JSC { 36 unsigned PropertyDescriptor::defaultAttributes = (DontDelete << 1) - 1; 37 38 bool PropertyDescriptor::writable() const 39 { 40 ASSERT(!isAccessorDescriptor()); 41 return !(m_attributes & ReadOnly); 42 } 43 44 bool PropertyDescriptor::enumerable() const 45 { 46 return !(m_attributes & DontEnum); 47 } 48 49 bool PropertyDescriptor::configurable() const 50 { 51 return !(m_attributes & DontDelete); 52 } 53 54 bool PropertyDescriptor::isDataDescriptor() const 55 { 56 return m_value || (m_seenAttributes & WritablePresent); 57 } 58 59 bool PropertyDescriptor::isGenericDescriptor() const 60 { 61 return !isAccessorDescriptor() && !isDataDescriptor(); 62 } 63 64 bool PropertyDescriptor::isAccessorDescriptor() const 65 { 66 return m_getter || m_setter; 67 } 68 69 void PropertyDescriptor::setUndefined() 70 { 71 m_value = jsUndefined(); 72 m_attributes = ReadOnly | DontDelete | DontEnum; 73 } 74 75 JSValue PropertyDescriptor::getter() const 76 { 77 ASSERT(isAccessorDescriptor()); 78 return m_getter; 79 } 80 81 JSValue PropertyDescriptor::setter() const 82 { 83 ASSERT(isAccessorDescriptor()); 84 return m_setter; 85 } 86 87 void PropertyDescriptor::setDescriptor(JSValue value, unsigned attributes) 88 { 89 ASSERT(value); 90 m_attributes = attributes; 91 if (attributes & (Getter | Setter)) { 92 GetterSetter* accessor = asGetterSetter(value); 93 m_getter = accessor->getter(); 94 m_setter = accessor->setter(); 95 ASSERT(m_getter || m_setter); 96 m_seenAttributes = EnumerablePresent | ConfigurablePresent; 97 m_attributes &= ~ReadOnly; 98 } else { 99 m_value = value; 100 m_seenAttributes = EnumerablePresent | ConfigurablePresent | WritablePresent; 101 } 102 } 103 104 void PropertyDescriptor::setAccessorDescriptor(JSValue getter, JSValue setter, unsigned attributes) 105 { 106 ASSERT(attributes & (Getter | Setter)); 107 ASSERT(getter || setter); 108 m_attributes = attributes; 109 m_getter = getter; 110 m_setter = setter; 111 m_attributes &= ~ReadOnly; 112 m_seenAttributes = EnumerablePresent | ConfigurablePresent; 113 } 114 115 void PropertyDescriptor::setWritable(bool writable) 116 { 117 if (writable) 118 m_attributes &= ~ReadOnly; 119 else 120 m_attributes |= ReadOnly; 121 m_seenAttributes |= WritablePresent; 122 } 123 124 void PropertyDescriptor::setEnumerable(bool enumerable) 125 { 126 if (enumerable) 127 m_attributes &= ~DontEnum; 128 else 129 m_attributes |= DontEnum; 130 m_seenAttributes |= EnumerablePresent; 131 } 132 133 void PropertyDescriptor::setConfigurable(bool configurable) 134 { 135 if (configurable) 136 m_attributes &= ~DontDelete; 137 else 138 m_attributes |= DontDelete; 139 m_seenAttributes |= ConfigurablePresent; 140 } 141 142 void PropertyDescriptor::setSetter(JSValue setter) 143 { 144 m_setter = setter; 145 m_attributes |= Setter; 146 m_attributes &= ~ReadOnly; 147 } 148 149 void PropertyDescriptor::setGetter(JSValue getter) 150 { 151 m_getter = getter; 152 m_attributes |= Getter; 153 m_attributes &= ~ReadOnly; 154 } 155 156 bool PropertyDescriptor::equalTo(ExecState* exec, const PropertyDescriptor& other) const 157 { 158 if (!other.m_value == m_value || 159 !other.m_getter == m_getter || 160 !other.m_setter == m_setter) 161 return false; 162 return (!m_value || JSValue::strictEqual(exec, other.m_value, m_value)) && 163 (!m_getter || JSValue::strictEqual(exec, other.m_getter, m_getter)) && 164 (!m_setter || JSValue::strictEqual(exec, other.m_setter, m_setter)) && 165 attributesEqual(other); 166 } 167 168 bool PropertyDescriptor::attributesEqual(const PropertyDescriptor& other) const 169 { 170 unsigned mismatch = other.m_attributes ^ m_attributes; 171 unsigned sharedSeen = other.m_seenAttributes & m_seenAttributes; 172 if (sharedSeen & WritablePresent && mismatch & ReadOnly) 173 return false; 174 if (sharedSeen & ConfigurablePresent && mismatch & DontDelete) 175 return false; 176 if (sharedSeen & EnumerablePresent && mismatch & DontEnum) 177 return false; 178 return true; 179 } 180 181 unsigned PropertyDescriptor::attributesWithOverride(const PropertyDescriptor& other) const 182 { 183 unsigned mismatch = other.m_attributes ^ m_attributes; 184 unsigned sharedSeen = other.m_seenAttributes & m_seenAttributes; 185 unsigned newAttributes = m_attributes & defaultAttributes; 186 if (sharedSeen & WritablePresent && mismatch & ReadOnly) 187 newAttributes ^= ReadOnly; 188 if (sharedSeen & ConfigurablePresent && mismatch & DontDelete) 189 newAttributes ^= DontDelete; 190 if (sharedSeen & EnumerablePresent && mismatch & DontEnum) 191 newAttributes ^= DontEnum; 192 return newAttributes; 193 } 194 195 } 196
