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/**
* This file is part of the DOM implementation for KDE.
*
* Copyright (C) 2005, 2006 Apple Computer, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#include "config.h"
#ifdef SKIP_STATIC_CONSTRUCTORS_ON_GCC
#define WEBCORE_QUALIFIEDNAME_HIDE_GLOBALS 1
#else
#define QNAME_DEFAULT_CONSTRUCTOR
#endif
#include "QualifiedName.h"
#include "StaticConstructors.h"
#include <wtf/Assertions.h>
#include <wtf/HashSet.h>
namespace WebCore {
struct QualifiedNameComponents {
StringImpl* m_prefix;
StringImpl* m_localName;
StringImpl* m_namespace;
};
// Golden ratio - arbitrary start value to avoid mapping all 0's to all 0's
static const unsigned PHI = 0x9e3779b9U;
static inline unsigned hashComponents(const QualifiedNameComponents& buf)
{
ASSERT(sizeof(QualifiedNameComponents) % (sizeof(uint16_t) * 2) == 0);
unsigned l = sizeof(QualifiedNameComponents) / (sizeof(uint16_t) * 2);
const uint16_t* s = reinterpret_cast<const uint16_t*>(&buf);
uint32_t hash = PHI;
// Main loop
for (; l > 0; l--) {
hash += s[0];
uint32_t tmp = (s[1] << 11) ^ hash;
hash = (hash << 16) ^ tmp;
s += 2;
hash += hash >> 11;
}
// Force "avalanching" of final 127 bits
hash ^= hash << 3;
hash += hash >> 5;
hash ^= hash << 2;
hash += hash >> 15;
hash ^= hash << 10;
// this avoids ever returning a hash code of 0, since that is used to
// signal "hash not computed yet", using a value that is likely to be
// effectively the same as 0 when the low bits are masked
if (hash == 0)
hash = 0x80000000;
return hash;
}
struct QNameHash {
static unsigned hash(const QualifiedName::QualifiedNameImpl* name) {
QualifiedNameComponents c = { name->m_prefix.impl(), name->m_localName.impl(), name->m_namespace.impl() };
return hashComponents(c);
}
static bool equal(const QualifiedName::QualifiedNameImpl* a, const QualifiedName::QualifiedNameImpl* b) { return a == b; }
static const bool safeToCompareToEmptyOrDeleted = false;
};
typedef HashSet<QualifiedName::QualifiedNameImpl*, QNameHash> QNameSet;
struct QNameComponentsTranslator {
static unsigned hash(const QualifiedNameComponents& components) {
return hashComponents(components);
}
static bool equal(QualifiedName::QualifiedNameImpl* name, const QualifiedNameComponents& c) {
return c.m_prefix == name->m_prefix.impl() && c.m_localName == name->m_localName.impl() && c.m_namespace == name->m_namespace.impl();
}
static void translate(QualifiedName::QualifiedNameImpl*& location, const QualifiedNameComponents& components, unsigned hash) {
location = QualifiedName::QualifiedNameImpl::create(components.m_prefix, components.m_localName, components.m_namespace).releaseRef();
}
};
static QNameSet* gNameCache;
QualifiedName::QualifiedName(const AtomicString& p, const AtomicString& l, const AtomicString& n)
: m_impl(0)
{
if (!gNameCache)
gNameCache = new QNameSet;
QualifiedNameComponents components = { p.impl(), l.impl(), n.impl() };
pair<QNameSet::iterator, bool> addResult = gNameCache->add<QualifiedNameComponents, QNameComponentsTranslator>(components);
m_impl = *addResult.first;
if (!addResult.second)
m_impl->ref();
}
QualifiedName::~QualifiedName()
{
deref();
}
QualifiedName::QualifiedName(const QualifiedName& other)
{
m_impl = other.m_impl;
ref();
}
const QualifiedName& QualifiedName::operator=(const QualifiedName& other)
{
if (m_impl != other.m_impl) {
deref();
m_impl = other.m_impl;
ref();
}
return *this;
}
void QualifiedName::deref()
{
#ifdef QNAME_DEFAULT_CONSTRUCTOR
if (!m_impl)
return;
#endif
if (m_impl->hasOneRef())
gNameCache->remove(m_impl);
m_impl->deref();
}
void QualifiedName::setPrefix(const AtomicString& prefix)
{
QualifiedName other(prefix, localName(), namespaceURI());
*this = other;
}
String QualifiedName::toString() const
{
String local = localName();
if (hasPrefix())
return prefix() + ":" + local;
return local;
}
// Global init routines
DEFINE_GLOBAL(QualifiedName, anyName, nullAtom, starAtom, starAtom)
void QualifiedName::init()
{
static bool initialized;
if (!initialized) {
// Use placement new to initialize the globals.
AtomicString::init();
new ((void*)&anyName) QualifiedName(nullAtom, starAtom, starAtom);
initialized = true;
}
}
}
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