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/*
* 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 "UStringImpl.h"
#include "Identifier.h"
#include "StdLibExtras.h"
#include "UString.h"
#include <wtf/unicode/UTF8.h>
using namespace WTF::Unicode;
using namespace std;
namespace JSC {
static const unsigned minLengthToShare = 20;
UStringImpl::~UStringImpl()
{
ASSERT(!isStatic());
if (isIdentifier())
Identifier::remove(this);
BufferOwnership ownership = bufferOwnership();
if (ownership != BufferInternal) {
if (ownership == BufferOwned) {
ASSERT(!m_sharedBuffer);
ASSERT(m_data);
fastFree(const_cast<UChar*>(m_data));
} else if (ownership == BufferSubstring) {
ASSERT(m_substringBuffer);
m_substringBuffer->deref();
} else {
ASSERT(ownership == BufferShared);
ASSERT(m_sharedBuffer);
m_sharedBuffer->deref();
}
}
}
UStringImpl* UStringImpl::empty()
{
// FIXME: This works around a bug in our port of PCRE, that a regular expression
// run on the empty string may still perform a read from the first element, and
// as such we need this to be a valid pointer. No code should ever be reading
// from a zero length string, so this should be able to be a non-null pointer
// into the zero-page.
// Replace this with 'reinterpret_cast<UChar*>(static_cast<intptr_t>(1))' once
// PCRE goes away.
static UChar emptyUCharData = 0;
DEFINE_STATIC_LOCAL(UStringImpl, emptyString, (&emptyUCharData, 0, ConstructStaticString));
return &emptyString;
}
PassRefPtr<UStringImpl> UStringImpl::createUninitialized(unsigned length, UChar*& data)
{
if (!length) {
data = 0;
return empty();
}
// Allocate a single buffer large enough to contain the StringImpl
// struct as well as the data which it contains. This removes one
// heap allocation from this call.
if (length > ((std::numeric_limits<size_t>::max() - sizeof(UStringImpl)) / sizeof(UChar)))
CRASH();
size_t size = sizeof(UStringImpl) + length * sizeof(UChar);
UStringImpl* string = static_cast<UStringImpl*>(fastMalloc(size));
data = reinterpret_cast<UChar*>(string + 1);
return adoptRef(new (string) UStringImpl(length));
}
PassRefPtr<UStringImpl> UStringImpl::create(const UChar* characters, unsigned length)
{
if (!characters || !length)
return empty();
UChar* data;
PassRefPtr<UStringImpl> string = createUninitialized(length, data);
memcpy(data, characters, length * sizeof(UChar));
return string;
}
PassRefPtr<UStringImpl> UStringImpl::create(const char* characters, unsigned length)
{
if (!characters || !length)
return empty();
UChar* data;
PassRefPtr<UStringImpl> string = createUninitialized(length, data);
for (unsigned i = 0; i != length; ++i) {
unsigned char c = characters[i];
data[i] = c;
}
return string;
}
PassRefPtr<UStringImpl> UStringImpl::create(const char* string)
{
if (!string)
return empty();
return create(string, strlen(string));
}
PassRefPtr<UStringImpl> UStringImpl::create(PassRefPtr<SharedUChar> sharedBuffer, const UChar* buffer, unsigned length)
{
if (!length)
return empty();
return adoptRef(new UStringImpl(buffer, length, sharedBuffer));
}
SharedUChar* UStringImpl::sharedBuffer()
{
if (m_length < minLengthToShare)
return 0;
// All static strings are smaller that the minimim length to share.
ASSERT(!isStatic());
BufferOwnership ownership = bufferOwnership();
if (ownership == BufferInternal)
return 0;
if (ownership == BufferSubstring)
return m_substringBuffer->sharedBuffer();
if (ownership == BufferOwned) {
ASSERT(!m_sharedBuffer);
m_sharedBuffer = SharedUChar::create(new SharableUChar(m_data)).releaseRef();
m_refCountAndFlags = (m_refCountAndFlags & ~s_refCountMaskBufferOwnership) | BufferShared;
}
ASSERT(bufferOwnership() == BufferShared);
ASSERT(m_sharedBuffer);
return m_sharedBuffer;
}
void URopeImpl::derefFibersNonRecursive(Vector<URopeImpl*, 32>& workQueue)
{
unsigned length = fiberCount();
for (unsigned i = 0; i < length; ++i) {
Fiber& fiber = fibers(i);
if (fiber->isRope()) {
URopeImpl* nextRope = static_cast<URopeImpl*>(fiber);
if (nextRope->hasOneRef())
workQueue.append(nextRope);
else
nextRope->deref();
} else
static_cast<UStringImpl*>(fiber)->deref();
}
}
void URopeImpl::destructNonRecursive()
{
Vector<URopeImpl*, 32> workQueue;
derefFibersNonRecursive(workQueue);
delete this;
while (!workQueue.isEmpty()) {
URopeImpl* rope = workQueue.last();
workQueue.removeLast();
rope->derefFibersNonRecursive(workQueue);
delete rope;
}
}
} // namespace JSC
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