/*
* Copyright (C) 1999 Lars Knoll (knoll@kde.org)
* (C) 1999 Antti Koivisto (koivisto@kde.org)
* (C) 2001 Dirk Mueller ( mueller@kde.org )
* Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
* Copyright (C) 2006 Andrew Wellington (proton@wiretapped.net)
*
* 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"
#include "StringImpl.h"
#include "AtomicString.h"
#include "CString.h"
#include "CharacterNames.h"
#include "FloatConversion.h"
#include "StringBuffer.h"
#include "StringHash.h"
#include "TextBreakIterator.h"
#include "TextEncoding.h"
#include "ThreadGlobalData.h"
#include <runtime/UString.h>
#include <wtf/dtoa.h>
#include <wtf/Assertions.h>
#include <wtf/Threading.h>
#include <wtf/unicode/Unicode.h>
using namespace WTF;
using namespace Unicode;
namespace WebCore {
static const unsigned minLengthToShare = 20;
static inline UChar* newUCharVector(unsigned n)
{
return static_cast<UChar*>(fastMalloc(sizeof(UChar) * n));
}
static inline void deleteUCharVector(const UChar* p)
{
fastFree(const_cast<UChar*>(p));
}
// Some of the factory methods create buffers using fastMalloc.
// We must ensure that all allocations of StringImpl are allocated using
// fastMalloc so that we don't have mis-matched frees. We accomplish
// this by overriding the new and delete operators.
void* StringImpl::operator new(size_t size, void* address)
{
if (address)
return address; // Allocating using an internal buffer
return fastMalloc(size);
}
void* StringImpl::operator new(size_t size)
{
return fastMalloc(size);
}
void StringImpl::operator delete(void* address)
{
fastFree(address);
}
// This constructor is used only to create the empty string.
StringImpl::StringImpl()
: m_data(0)
, m_length(0)
, m_hash(0)
{
// Ensure that the hash is computed so that AtomicStringHash can call existingHash()
// with impunity. The empty string is special because it is never entered into
// AtomicString's HashKey, but still needs to compare correctly.
hash();
}
inline StringImpl::StringImpl(const UChar* characters, unsigned length)
: m_data(characters)
, m_length(length)
, m_hash(0)
{
ASSERT(characters);
ASSERT(length);
ASSERT(!bufferIsInternal());
}
inline StringImpl::StringImpl(unsigned length)
: m_data(reinterpret_cast<const UChar*>(this + 1))
, m_length(length)
, m_hash(0)
{
ASSERT(length);
ASSERT(bufferIsInternal());
}
StringImpl::~StringImpl()
{
if (inTable())
AtomicString::remove(this);
if (!bufferIsInternal()) {
SharedUChar* sharedBuffer = m_sharedBufferAndFlags.get();
if (sharedBuffer)
sharedBuffer->deref();
else
deleteUCharVector(m_data);
}
}
StringImpl* StringImpl::empty()
{
return threadGlobalData().emptyString();
}
bool StringImpl::containsOnlyWhitespace()
{
// FIXME: The definition of whitespace here includes a number of characters
// that are not whitespace from the point of view of RenderText; I wonder if
// that's a problem in practice.
for (unsigned i = 0; i < m_length; i++)
if (!isASCIISpace(m_data[i]))
return false;
return true;
}
PassRefPtr<StringImpl> StringImpl::substring(unsigned start, unsigned length)
{
if (start >= m_length)
return empty();
unsigned maxLength = m_length - start;
if (length >= maxLength) {
if (!start)
return this;
length = maxLength;
}
return create(m_data + start, length);
}
UChar32 StringImpl::characterStartingAt(unsigned i)
{
if (U16_IS_SINGLE(m_data[i]))
return m_data[i];
if (i + 1 < m_length && U16_IS_LEAD(m_data[i]) && U16_IS_TRAIL(m_data[i + 1]))
return U16_GET_SUPPLEMENTARY(m_data[i], m_data[i + 1]);
return 0;
}
PassRefPtr<StringImpl> StringImpl::lower()
{
// Note: This is a hot function in the Dromaeo benchmark, specifically the
// no-op code path up through the first 'return' statement.
// First scan the string for uppercase and non-ASCII characters:
UChar ored = 0;
bool noUpper = true;
const UChar *end = m_data + m_length;
for (const UChar* chp = m_data; chp != end; chp++) {
if (UNLIKELY(isASCIIUpper(*chp)))
noUpper = false;
ored |= *chp;
}
// Nothing to do if the string is all ASCII with no uppercase.
if (noUpper && !(ored & ~0x7F))
return this;
int32_t length = m_length;
UChar* data;
RefPtr<StringImpl> newImpl = createUninitialized(m_length, data);
if (!(ored & ~0x7F)) {
// Do a faster loop for the case where all the characters are ASCII.
for (int i = 0; i < length; i++) {
UChar c = m_data[i];
data[i] = toASCIILower(c);
}
return newImpl;
}
// Do a slower implementation for cases that include non-ASCII characters.
bool error;
int32_t realLength = Unicode::toLower(data, length, m_data, m_length, &error);
if (!error && realLength == length)
return newImpl;
newImpl = createUninitialized(realLength, data);
Unicode::toLower(data, realLength, m_data, m_length, &error);
if (error)
return this;
return newImpl;
}
PassRefPtr<StringImpl> StringImpl::upper()
{
// This function could be optimized for no-op cases the way lower() is,
// but in empirical testing, few actual calls to upper() are no-ops, so
// it wouldn't be worth the extra time for pre-scanning.
UChar* data;
PassRefPtr<StringImpl> newImpl = createUninitialized(m_length, data);
int32_t length = m_length;
// Do a faster loop for the case where all the characters are ASCII.
UChar ored = 0;
for (int i = 0; i < length; i++) {
UChar c = m_data[i];
ored |= c;
data[i] = toASCIIUpper(c);
}
if (!(ored & ~0x7F))
return newImpl;
// Do a slower implementation for cases that include non-ASCII characters.
bool error;
int32_t realLength = Unicode::toUpper(data, length, m_data, m_length, &error);
if (!error && realLength == length)
return newImpl;
newImpl = createUninitialized(realLength, data);
Unicode::toUpper(data, realLength, m_data, m_length, &error);
if (error)
return this;
return newImpl;
}
PassRefPtr<StringImpl> StringImpl::secure(UChar aChar)
{
UChar* data;
PassRefPtr<StringImpl> newImpl = createUninitialized(m_length, data);
int32_t length = m_length;
for (int i = 0; i < length; ++i)
data[i] = aChar;
return newImpl;
}
PassRefPtr<StringImpl> StringImpl::foldCase()
{
UChar* data;
PassRefPtr<StringImpl> newImpl = createUninitialized(m_length, data);
int32_t length = m_length;
// Do a faster loop for the case where all the characters are ASCII.
UChar ored = 0;
for (int i = 0; i < length; i++) {
UChar c = m_data[i];
ored |= c;
data[i] = toASCIILower(c);
}
if (!(ored & ~0x7F))
return newImpl;
// Do a slower implementation for cases that include non-ASCII characters.
bool error;
int32_t realLength = Unicode::foldCase(data, length, m_data, m_length, &error);
if (!error && realLength == length)
return newImpl;
newImpl = createUninitialized(realLength, data);
Unicode::foldCase(data, realLength, m_data, m_length, &error);
if (error)
return this;
return newImpl;
}
PassRefPtr<StringImpl> StringImpl::stripWhiteSpace()
{
if (!m_length)
return empty();
unsigned start = 0;
unsigned end = m_length - 1;
// skip white space from start
while (start <= end && isSpaceOrNewline(m_data[start]))
start++;
// only white space
if (start > end)
return empty();
// skip white space from end
while (end && isSpaceOrNewline(m_data[end]))
end--;
if (!start && end == m_length - 1)
return this;
return create(m_data + start, end + 1 - start);
}
PassRefPtr<StringImpl> StringImpl::removeCharacters(CharacterMatchFunctionPtr findMatch)
{
const UChar* from = m_data;
const UChar* fromend = from + m_length;
// Assume the common case will not remove any characters
while (from != fromend && !findMatch(*from))
from++;
if (from == fromend)
return this;
StringBuffer data(m_length);
UChar* to = data.characters();
unsigned outc = from - m_data;
if (outc)
memcpy(to, m_data, outc * sizeof(UChar));
while (true) {
while (from != fromend && findMatch(*from))
from++;
while (from != fromend && !findMatch(*from))
to[outc++] = *from++;
if (from == fromend)
break;
}
data.shrink(outc);
return adopt(data);
}
PassRefPtr<StringImpl> StringImpl::simplifyWhiteSpace()
{
StringBuffer data(m_length);
const UChar* from = m_data;
const UChar* fromend = from + m_length;
int outc = 0;
bool changedToSpace = false;
UChar* to = data.characters();
while (true) {
while (from != fromend && isSpaceOrNewline(*from)) {
if (*from != ' ')
changedToSpace = true;
from++;
}
while (from != fromend && !isSpaceOrNewline(*from))
to[outc++] = *from++;
if (from != fromend)
to[outc++] = ' ';
else
break;
}
if (outc > 0 && to[outc - 1] == ' ')
outc--;
if (static_cast<unsigned>(outc) == m_length && !changedToSpace)
return this;
data.shrink(outc);
return adopt(data);
}
PassRefPtr<StringImpl> StringImpl::capitalize(UChar previous)
{
StringBuffer stringWithPrevious(m_length + 1);
stringWithPrevious[0] = previous == noBreakSpace ? ' ' : previous;
for (unsigned i = 1; i < m_length + 1; i++) {
// Replace   with a real space since ICU no longer treats   as a word separator.
if (m_data[i - 1] == noBreakSpace)
stringWithPrevious[i] = ' ';
else
stringWithPrevious[i] = m_data[i - 1];
}
TextBreakIterator* boundary = wordBreakIterator(stringWithPrevious.characters(), m_length + 1);
if (!boundary)
return this;
StringBuffer data(m_length);
int32_t endOfWord;
int32_t startOfWord = textBreakFirst(boundary);
for (endOfWord = textBreakNext(boundary); endOfWord != TextBreakDone; startOfWord = endOfWord, endOfWord = textBreakNext(boundary)) {
if (startOfWord != 0) // Ignore first char of previous string
data[startOfWord - 1] = m_data[startOfWord - 1] == noBreakSpace ? noBreakSpace : toTitleCase(stringWithPrevious[startOfWord]);
for (int i = startOfWord + 1; i < endOfWord; i++)
data[i - 1] = m_data[i - 1];
}
return adopt(data);
}
int StringImpl::toIntStrict(bool* ok, int base)
{
return charactersToIntStrict(m_data, m_length, ok, base);
}
unsigned StringImpl::toUIntStrict(bool* ok, int base)
{
return charactersToUIntStrict(m_data, m_length, ok, base);
}
int64_t StringImpl::toInt64Strict(bool* ok, int base)
{
return charactersToInt64Strict(m_data, m_length, ok, base);
}
uint64_t StringImpl::toUInt64Strict(bool* ok, int base)
{
return charactersToUInt64Strict(m_data, m_length, ok, base);
}
intptr_t StringImpl::toIntPtrStrict(bool* ok, int base)
{
return charactersToIntPtrStrict(m_data, m_length, ok, base);
}
int StringImpl::toInt(bool* ok)
{
return charactersToInt(m_data, m_length, ok);
}
unsigned StringImpl::toUInt(bool* ok)
{
return charactersToUInt(m_data, m_length, ok);
}
int64_t StringImpl::toInt64(bool* ok)
{
return charactersToInt64(m_data, m_length, ok);
}
uint64_t StringImpl::toUInt64(bool* ok)
{
return charactersToUInt64(m_data, m_length, ok);
}
intptr_t StringImpl::toIntPtr(bool* ok)
{
return charactersToIntPtr(m_data, m_length, ok);
}
double StringImpl::toDouble(bool* ok)
{
return charactersToDouble(m_data, m_length, ok);
}
float StringImpl::toFloat(bool* ok)
{
return charactersToFloat(m_data, m_length, ok);
}
static bool equal(const UChar* a, const char* b, int length)
{
ASSERT(length >= 0);
while (length--) {
unsigned char bc = *b++;
if (*a++ != bc)
return false;
}
return true;
}
bool equalIgnoringCase(const UChar* a, const char* b, unsigned length)
{
while (length--) {
unsigned char bc = *b++;
if (foldCase(*a++) != foldCase(bc))
return false;
}
return true;
}
static inline bool equalIgnoringCase(const UChar* a, const UChar* b, int length)
{
ASSERT(length >= 0);
return umemcasecmp(a, b, length) == 0;
}
int StringImpl::find(const char* chs, int index, bool caseSensitive)
{
if (!chs || index < 0)
return -1;
int chsLength = strlen(chs);
int n = m_length - index;
if (n < 0)
return -1;
n -= chsLength - 1;
if (n <= 0)
return -1;
const char* chsPlusOne = chs + 1;
int chsLengthMinusOne = chsLength - 1;
const UChar* ptr = m_data + index - 1;
if (caseSensitive) {
UChar c = *chs;
do {
if (*++ptr == c && equal(ptr + 1, chsPlusOne, chsLengthMinusOne))
return m_length - chsLength - n + 1;
} while (--n);
} else {
UChar lc = Unicode::foldCase(*chs);
do {
if (Unicode::foldCase(*++ptr) == lc && equalIgnoringCase(ptr + 1, chsPlusOne, chsLengthMinusOne))
return m_length - chsLength - n + 1;
} while (--n);
}
return -1;
}
int StringImpl::find(UChar c, int start)
{
return WebCore::find(m_data, m_length, c, start);
}
int StringImpl::find(CharacterMatchFunctionPtr matchFunction, int start)
{
return WebCore::find(m_data, m_length, matchFunction, start);
}
int StringImpl::find(StringImpl* str, int index, bool caseSensitive)
{
/*
We use a simple trick for efficiency's sake. Instead of
comparing strings, we compare the sum of str with that of
a part of this string. Only if that matches, we call memcmp
or ucstrnicmp.
*/
ASSERT(str);
if (index < 0)
index += m_length;
int lstr = str->m_length;
int lthis = m_length - index;
if ((unsigned)lthis > m_length)
return -1;
int delta = lthis - lstr;
if (delta < 0)
return -1;
const UChar* uthis = m_data + index;
const UChar* ustr = str->m_data;
unsigned hthis = 0;
unsigned hstr = 0;
if (caseSensitive) {
for (int i = 0; i < lstr; i++) {
hthis += uthis[i];
hstr += ustr[i];
}
int i = 0;
while (1) {
if (hthis == hstr && memcmp(uthis + i, ustr, lstr * sizeof(UChar)) == 0)
return index + i;
if (i == delta)
return -1;
hthis += uthis[i + lstr];
hthis -= uthis[i];
i++;
}
} else {
for (int i = 0; i < lstr; i++ ) {
hthis += toASCIILower(uthis[i]);
hstr += toASCIILower(ustr[i]);
}
int i = 0;
while (1) {
if (hthis == hstr && equalIgnoringCase(uthis + i, ustr, lstr))
return index + i;
if (i == delta)
return -1;
hthis += toASCIILower(uthis[i + lstr]);
hthis -= toASCIILower(uthis[i]);
i++;
}
}
}
int StringImpl::reverseFind(UChar c, int index)
{
return WebCore::reverseFind(m_data, m_length, c, index);
}
int StringImpl::reverseFind(StringImpl* str, int index, bool caseSensitive)
{
/*
See StringImpl::find() for explanations.
*/
ASSERT(str);
int lthis = m_length;
if (index < 0)
index += lthis;
int lstr = str->m_length;
int delta = lthis - lstr;
if ( index < 0 || index > lthis || delta < 0 )
return -1;
if ( index > delta )
index = delta;
const UChar *uthis = m_data;
const UChar *ustr = str->m_data;
unsigned hthis = 0;
unsigned hstr = 0;
int i;
if (caseSensitive) {
for ( i = 0; i < lstr; i++ ) {
hthis += uthis[index + i];
hstr += ustr[i];
}
i = index;
while (1) {
if (hthis == hstr && memcmp(uthis + i, ustr, lstr * sizeof(UChar)) == 0)
return i;
if (i == 0)
return -1;
i--;
hthis -= uthis[i + lstr];
hthis += uthis[i];
}
} else {
for (i = 0; i < lstr; i++) {
hthis += toASCIILower(uthis[index + i]);
hstr += toASCIILower(ustr[i]);
}
i = index;
while (1) {
if (hthis == hstr && equalIgnoringCase(uthis + i, ustr, lstr) )
return i;
if (i == 0)
return -1;
i--;
hthis -= toASCIILower(uthis[i + lstr]);
hthis += toASCIILower(uthis[i]);
}
}
// Should never get here.
return -1;
}
bool StringImpl::endsWith(StringImpl* m_data, bool caseSensitive)
{
ASSERT(m_data);
int start = m_length - m_data->m_length;
if (start >= 0)
return (find(m_data, start, caseSensitive) == start);
return false;
}
PassRefPtr<StringImpl> StringImpl::replace(UChar oldC, UChar newC)
{
if (oldC == newC)
return this;
unsigned i;
for (i = 0; i != m_length; ++i)
if (m_data[i] == oldC)
break;
if (i == m_length)
return this;
UChar* data;
PassRefPtr<StringImpl> newImpl = createUninitialized(m_length, data);
for (i = 0; i != m_length; ++i) {
UChar ch = m_data[i];
if (ch == oldC)
ch = newC;
data[i] = ch;
}
return newImpl;
}
PassRefPtr<StringImpl> StringImpl::replace(unsigned position, unsigned lengthToReplace, StringImpl* str)
{
position = min(position, length());
lengthToReplace = min(lengthToReplace, length() - position);
unsigned lengthToInsert = str ? str->length() : 0;
if (!lengthToReplace && !lengthToInsert)
return this;
UChar* data;
PassRefPtr<StringImpl> newImpl =
createUninitialized(length() - lengthToReplace + lengthToInsert, data);
memcpy(data, characters(), position * sizeof(UChar));
if (str)
memcpy(data + position, str->characters(), lengthToInsert * sizeof(UChar));
memcpy(data + position + lengthToInsert, characters() + position + lengthToReplace,
(length() - position - lengthToReplace) * sizeof(UChar));
return newImpl;
}
PassRefPtr<StringImpl> StringImpl::replace(UChar pattern, StringImpl* replacement)
{
if (!replacement)
return this;
int repStrLength = replacement->length();
int srcSegmentStart = 0;
int matchCount = 0;
// Count the matches
while ((srcSegmentStart = find(pattern, srcSegmentStart)) >= 0) {
++matchCount;
++srcSegmentStart;
}
// If we have 0 matches, we don't have to do any more work
if (!matchCount)
return this;
UChar* data;
PassRefPtr<StringImpl> newImpl =
createUninitialized(m_length - matchCount + (matchCount * repStrLength), data);
// Construct the new data
int srcSegmentEnd;
int srcSegmentLength;
srcSegmentStart = 0;
int dstOffset = 0;
while ((srcSegmentEnd = find(pattern, srcSegmentStart)) >= 0) {
srcSegmentLength = srcSegmentEnd - srcSegmentStart;
memcpy(data + dstOffset, m_data + srcSegmentStart, srcSegmentLength * sizeof(UChar));
dstOffset += srcSegmentLength;
memcpy(data + dstOffset, replacement->m_data, repStrLength * sizeof(UChar));
dstOffset += repStrLength;
srcSegmentStart = srcSegmentEnd + 1;
}
srcSegmentLength = m_length - srcSegmentStart;
memcpy(data + dstOffset, m_data + srcSegmentStart, srcSegmentLength * sizeof(UChar));
ASSERT(dstOffset + srcSegmentLength == static_cast<int>(newImpl->length()));
return newImpl;
}
PassRefPtr<StringImpl> StringImpl::replace(StringImpl* pattern, StringImpl* replacement)
{
if (!pattern || !replacement)
return this;
int patternLength = pattern->length();
if (!patternLength)
return this;
int repStrLength = replacement->length();
int srcSegmentStart = 0;
int matchCount = 0;
// Count the matches
while ((srcSegmentStart = find(pattern, srcSegmentStart)) >= 0) {
++matchCount;
srcSegmentStart += patternLength;
}
// If we have 0 matches, we don't have to do any more work
if (!matchCount)
return this;
UChar* data;
PassRefPtr<StringImpl> newImpl =
createUninitialized(m_length + matchCount * (repStrLength - patternLength), data);
// Construct the new data
int srcSegmentEnd;
int srcSegmentLength;
srcSegmentStart = 0;
int dstOffset = 0;
while ((srcSegmentEnd = find(pattern, srcSegmentStart)) >= 0) {
srcSegmentLength = srcSegmentEnd - srcSegmentStart;
memcpy(data + dstOffset, m_data + srcSegmentStart, srcSegmentLength * sizeof(UChar));
dstOffset += srcSegmentLength;
memcpy(data + dstOffset, replacement->m_data, repStrLength * sizeof(UChar));
dstOffset += repStrLength;
srcSegmentStart = srcSegmentEnd + patternLength;
}
srcSegmentLength = m_length - srcSegmentStart;
memcpy(data + dstOffset, m_data + srcSegmentStart, srcSegmentLength * sizeof(UChar));
ASSERT(dstOffset + srcSegmentLength == static_cast<int>(newImpl->length()));
return newImpl;
}
bool equal(StringImpl* a, StringImpl* b)
{
return StringHash::equal(a, b);
}
bool equal(StringImpl* a, const char* b)
{
if (!a)
return !b;
if (!b)
return !a;
unsigned length = a->length();
const UChar* as = a->characters();
for (unsigned i = 0; i != length; ++i) {
unsigned char bc = b[i];
if (!bc)
return false;
if (as[i] != bc)
return false;
}
return !b[length];
}
bool equalIgnoringCase(StringImpl* a, StringImpl* b)
{
return CaseFoldingHash::equal(a, b);
}
bool equalIgnoringCase(StringImpl* a, const char* b)
{
if (!a)
return !b;
if (!b)
return !a;
unsigned length = a->length();
const UChar* as = a->characters();
// Do a faster loop for the case where all the characters are ASCII.
UChar ored = 0;
bool equal = true;
for (unsigned i = 0; i != length; ++i) {
char bc = b[i];
if (!bc)
return false;
UChar ac = as[i];
ored |= ac;
equal = equal && (toASCIILower(ac) == toASCIILower(bc));
}
// Do a slower implementation for cases that include non-ASCII characters.
if (ored & ~0x7F) {
equal = true;
for (unsigned i = 0; i != length; ++i) {
unsigned char bc = b[i];
equal = equal && (foldCase(as[i]) == foldCase(bc));
}
}
return equal && !b[length];
}
bool equalIgnoringNullity(StringImpl* a, StringImpl* b)
{
if (StringHash::equal(a, b))
return true;
if (!a && b && !b->length())
return true;
if (!b && a && !a->length())
return true;
return false;
}
Vector<char> StringImpl::ascii()
{
Vector<char> buffer(m_length + 1);
for (unsigned i = 0; i != m_length; ++i) {
UChar c = m_data[i];
if ((c >= 0x20 && c < 0x7F) || c == 0x00)
buffer[i] = c;
else
buffer[i] = '?';
}
buffer[m_length] = '\0';
return buffer;
}
WTF::Unicode::Direction StringImpl::defaultWritingDirection()
{
for (unsigned i = 0; i < m_length; ++i) {
WTF::Unicode::Direction charDirection = WTF::Unicode::direction(m_data[i]);
if (charDirection == WTF::Unicode::LeftToRight)
return WTF::Unicode::LeftToRight;
if (charDirection == WTF::Unicode::RightToLeft || charDirection == WTF::Unicode::RightToLeftArabic)
return WTF::Unicode::RightToLeft;
}
return WTF::Unicode::LeftToRight;
}
// This is a hot function because it's used when parsing HTML.
PassRefPtr<StringImpl> StringImpl::createStrippingNullCharactersSlowCase(const UChar* characters, unsigned length)
{
StringBuffer strippedCopy(length);
unsigned strippedLength = 0;
for (unsigned i = 0; i < length; i++) {
if (int c = characters[i])
strippedCopy[strippedLength++] = c;
}
ASSERT(strippedLength < length); // Only take the slow case when stripping.
strippedCopy.shrink(strippedLength);
return adopt(strippedCopy);
}
PassRefPtr<StringImpl> StringImpl::adopt(StringBuffer& buffer)
{
unsigned length = buffer.length();
if (length == 0)
return empty();
return adoptRef(new StringImpl(buffer.release(), length));
}
PassRefPtr<StringImpl> StringImpl::adopt(Vector<UChar>& vector)
{
size_t size = vector.size();
if (size == 0)
return empty();
return adoptRef(new StringImpl(vector.releaseBuffer(), size));
}
PassRefPtr<StringImpl> StringImpl::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.
size_t size = sizeof(StringImpl) + length * sizeof(UChar);
StringImpl* string = static_cast<StringImpl*>(fastMalloc(size));
data = reinterpret_cast<UChar*>(string + 1);
string = new (string) StringImpl(length);
return adoptRef(string);
}
PassRefPtr<StringImpl> StringImpl::create(const UChar* characters, unsigned length)
{
if (!characters || !length)
return empty();
UChar* data;
PassRefPtr<StringImpl> string = createUninitialized(length, data);
memcpy(data, characters, length * sizeof(UChar));
return string;
}
PassRefPtr<StringImpl> StringImpl::create(const char* characters, unsigned length)
{
if (!characters || !length)
return empty();
UChar* data;
PassRefPtr<StringImpl> string = createUninitialized(length, data);
for (unsigned i = 0; i != length; ++i) {
unsigned char c = characters[i];
data[i] = c;
}
return string;
}
PassRefPtr<StringImpl> StringImpl::create(const char* string)
{
if (!string)
return empty();
return create(string, strlen(string));
}
#if USE(JSC)
PassRefPtr<StringImpl> StringImpl::create(const JSC::UString& str)
{
SharedUChar* sharedBuffer = const_cast<JSC::UString*>(&str)->rep()->sharedBuffer();
if (sharedBuffer) {
PassRefPtr<StringImpl> impl = adoptRef(new StringImpl(str.data(), str.size()));
sharedBuffer->ref();
impl->m_sharedBufferAndFlags.set(sharedBuffer);
return impl;
}
return StringImpl::create(str.data(), str.size());
}
JSC::UString StringImpl::ustring()
{
SharedUChar* sharedBuffer = this->sharedBuffer();
if (sharedBuffer)
return JSC::UString::Rep::create(sharedBuffer, const_cast<UChar*>(m_data), m_length);
return JSC::UString(m_data, m_length);
}
#endif
PassRefPtr<StringImpl> StringImpl::createWithTerminatingNullCharacter(const StringImpl& string)
{
// Use createUninitialized instead of 'new StringImpl' so that the string and its buffer
// get allocated in a single malloc block.
UChar* data;
int length = string.m_length;
RefPtr<StringImpl> terminatedString = createUninitialized(length + 1, data);
memcpy(data, string.m_data, length * sizeof(UChar));
data[length] = 0;
terminatedString->m_length--;
terminatedString->m_hash = string.m_hash;
terminatedString->m_sharedBufferAndFlags.setFlag(HasTerminatingNullCharacter);
return terminatedString.release();
}
PassRefPtr<StringImpl> StringImpl::threadsafeCopy() const
{
// Special-case empty strings to make sure that per-thread empty string instance isn't returned.
if (m_length == 0)
return adoptRef(new StringImpl);
return create(m_data, m_length);
}
PassRefPtr<StringImpl> StringImpl::crossThreadString()
{
SharedUChar* shared = sharedBuffer();
if (shared) {
RefPtr<StringImpl> impl = adoptRef(new StringImpl(m_data, m_length));
impl->m_sharedBufferAndFlags.set(shared->crossThreadCopy().releaseRef());
return impl.release();
}
// If no shared buffer is available, create a copy.
return threadsafeCopy();
}
StringImpl::SharedUChar* StringImpl::sharedBuffer()
{
if (m_length < minLengthToShare || bufferIsInternal())
return 0;
if (!m_sharedBufferAndFlags.get())
m_sharedBufferAndFlags.set(SharedUChar::create(new OwnFastMallocPtr<UChar>(const_cast<UChar*>(m_data))).releaseRef());
return m_sharedBufferAndFlags.get();
}
} // namespace WebCore