JavaScriptCore/runtime/PropertyDescriptor.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/JavaScriptCore/runtime/PropertyDescriptor.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,195 @@
+/*
+ * Copyright (C) 2009 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+
+#include "config.h"
+
+#include "PropertyDescriptor.h"
+
+#include "GetterSetter.h"
+#include "JSObject.h"
+#include "Operations.h"
+
+namespace JSC {
+unsigned PropertyDescriptor::defaultAttributes = (DontDelete << 1) - 1;
+
+bool PropertyDescriptor::writable() const
+{
+    ASSERT(!isAccessorDescriptor());
+    return !(m_attributes & ReadOnly);
+}
+
+bool PropertyDescriptor::enumerable() const
+{
+    return !(m_attributes & DontEnum);
+}
+
+bool PropertyDescriptor::configurable() const
+{
+    return !(m_attributes & DontDelete);
+}
+
+bool PropertyDescriptor::isDataDescriptor() const
+{
+    return m_value || (m_seenAttributes & WritablePresent);
+}
+
+bool PropertyDescriptor::isGenericDescriptor() const
+{
+    return !isAccessorDescriptor() && !isDataDescriptor();
+}
+
+bool PropertyDescriptor::isAccessorDescriptor() const
+{
+    return m_getter || m_setter;
+}
+
+void PropertyDescriptor::setUndefined()
+{
+    m_value = jsUndefined();
+    m_attributes = ReadOnly | DontDelete | DontEnum;
+}
+
+JSValue PropertyDescriptor::getter() const
+{
+    ASSERT(isAccessorDescriptor());
+    return m_getter;
+}
+
+JSValue PropertyDescriptor::setter() const
+{
+    ASSERT(isAccessorDescriptor());
+    return m_setter;
+}
+
+void PropertyDescriptor::setDescriptor(JSValue value, unsigned attributes)
+{
+    ASSERT(value);
+    m_attributes = attributes;
+    if (attributes & (Getter | Setter)) {
+        GetterSetter* accessor = asGetterSetter(value);
+        m_getter = accessor->getter();
+        m_setter = accessor->setter();
+        ASSERT(m_getter || m_setter);
+        m_seenAttributes = EnumerablePresent | ConfigurablePresent;
+        m_attributes &= ~ReadOnly;
+    } else {
+        m_value = value;
+        m_seenAttributes = EnumerablePresent | ConfigurablePresent | WritablePresent;
+    }
+}
+
+void PropertyDescriptor::setAccessorDescriptor(JSValue getter, JSValue setter, unsigned attributes)
+{
+    ASSERT(attributes & (Getter | Setter));
+    ASSERT(getter || setter);
+    m_attributes = attributes;
+    m_getter = getter;
+    m_setter = setter;
+    m_attributes &= ~ReadOnly;
+    m_seenAttributes = EnumerablePresent | ConfigurablePresent;
+}
+
+void PropertyDescriptor::setWritable(bool writable)
+{
+    if (writable)
+        m_attributes &= ~ReadOnly;
+    else
+        m_attributes |= ReadOnly;
+    m_seenAttributes |= WritablePresent;
+}
+
+void PropertyDescriptor::setEnumerable(bool enumerable)
+{
+    if (enumerable)
+        m_attributes &= ~DontEnum;
+    else
+        m_attributes |= DontEnum;
+    m_seenAttributes |= EnumerablePresent;
+}
+
+void PropertyDescriptor::setConfigurable(bool configurable)
+{
+    if (configurable)
+        m_attributes &= ~DontDelete;
+    else
+        m_attributes |= DontDelete;
+    m_seenAttributes |= ConfigurablePresent;
+}
+
+void PropertyDescriptor::setSetter(JSValue setter)
+{
+    m_setter = setter;
+    m_attributes |= Setter;
+    m_attributes &= ~ReadOnly;
+}
+
+void PropertyDescriptor::setGetter(JSValue getter)
+{
+    m_getter = getter;
+    m_attributes |= Getter;
+    m_attributes &= ~ReadOnly;
+}
+
+bool PropertyDescriptor::equalTo(ExecState* exec, const PropertyDescriptor& other) const
+{
+    if (!other.m_value == m_value ||
+        !other.m_getter == m_getter ||
+        !other.m_setter == m_setter)
+        return false;
+    return (!m_value || JSValue::strictEqual(exec, other.m_value, m_value)) && 
+           (!m_getter || JSValue::strictEqual(exec, other.m_getter, m_getter)) && 
+           (!m_setter || JSValue::strictEqual(exec, other.m_setter, m_setter)) &&
+           attributesEqual(other);
+}
+
+bool PropertyDescriptor::attributesEqual(const PropertyDescriptor& other) const
+{
+    unsigned mismatch = other.m_attributes ^ m_attributes;
+    unsigned sharedSeen = other.m_seenAttributes & m_seenAttributes;
+    if (sharedSeen & WritablePresent && mismatch & ReadOnly)
+        return false;
+    if (sharedSeen & ConfigurablePresent && mismatch & DontDelete)
+        return false;
+    if (sharedSeen & EnumerablePresent && mismatch & DontEnum)
+        return false;
+    return true;
+}
+
+unsigned PropertyDescriptor::attributesWithOverride(const PropertyDescriptor& other) const
+{
+    unsigned mismatch = other.m_attributes ^ m_attributes;
+    unsigned sharedSeen = other.m_seenAttributes & m_seenAttributes;
+    unsigned newAttributes = m_attributes & defaultAttributes;
+    if (sharedSeen & WritablePresent && mismatch & ReadOnly)
+        newAttributes ^= ReadOnly;
+    if (sharedSeen & ConfigurablePresent && mismatch & DontDelete)
+        newAttributes ^= DontDelete;
+    if (sharedSeen & EnumerablePresent && mismatch & DontEnum)
+        newAttributes ^= DontEnum;
+    return newAttributes;
+}
+
+}