Source/wtf/text/WTFString.cpp

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This source file includes following definitions.
append
appendInternal
append
append
codePointCompare
insert
append
append
insertInternal
insert
insert
characterStartingAt
ensure16Bit
truncate
removeInternal
remove
substring
lower
upper
lower
upper
stripWhiteSpace
stripWhiteSpace
simplifyWhiteSpace
simplifyWhiteSpace
removeCharacters
foldCase
percentage
charactersWithNullTermination
copyTo
format
number
number
number
number
number
number
number
numberToStringECMAScript
numberToStringFixedWidth
toIntStrict
toUIntStrict
toInt64Strict
toUInt64Strict
toIntPtrStrict
toInt
toUInt
toInt64
toUInt64
toIntPtr
toDouble
toFloat
isolatedCopy
isSafeToSendToAnotherThread
split
split
ascii
latin1
putUTF8Triple
utf8
make8BitFrom16BitSource
make16BitFrom8BitSource
fromUTF8
fromUTF8
fromUTF8
fromUTF8WithLatin1Fallback
isCharacterAllowedInBase
toIntegralType
lengthOfCharactersAsInteger
charactersToIntStrict
charactersToIntStrict
charactersToUIntStrict
charactersToUIntStrict
charactersToInt64Strict
charactersToInt64Strict
charactersToUInt64Strict
charactersToUInt64Strict
charactersToIntPtrStrict
charactersToIntPtrStrict
charactersToInt
charactersToInt
charactersToUInt
charactersToUInt
charactersToInt64
charactersToInt64
charactersToUInt64
charactersToUInt64
charactersToIntPtr
charactersToIntPtr
toDoubleType
charactersToDouble
charactersToDouble
charactersToFloat
charactersToFloat
charactersToFloat
charactersToFloat
emptyString
show
string
asciiDebug
asciiDebug
/*
 * (C) 1999 Lars Knoll (knoll@kde.org)
 * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2010, 2012 Apple Inc. All rights reserved.
 * Copyright (C) 2007-2009 Torch Mobile, 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"
#include "WTFString.h"

#include "IntegerToStringConversion.h"
#include <stdarg.h>
#include "wtf/ASCIICType.h"
#include "wtf/DataLog.h"
#include "wtf/HexNumber.h"
#include "wtf/MathExtras.h"
#include "wtf/text/CString.h"
#include "wtf/StringExtras.h"
#include "wtf/Vector.h"
#include "wtf/dtoa.h"
#include "wtf/unicode/CharacterNames.h"
#include "wtf/unicode/UTF8.h"
#include "wtf/unicode/Unicode.h"

using namespace std;

namespace WTF {

using namespace Unicode;
using namespace std;

// Construct a string with UTF-16 data.
String::String(const UChar* characters, unsigned length)
    : m_impl(characters ? StringImpl::create(characters, length) : nullptr)
{
}

// Construct a string with UTF-16 data, from a null-terminated source.
String::String(const UChar* str)
{
    if (!str)
        return;
    m_impl = StringImpl::create(str, lengthOfNullTerminatedString(str));
}

// Construct a string with latin1 data.
String::String(const LChar* characters, unsigned length)
    : m_impl(characters ? StringImpl::create(characters, length) : nullptr)
{
}

String::String(const char* characters, unsigned length)
    : m_impl(characters ? StringImpl::create(reinterpret_cast<const LChar*>(characters), length) : nullptr)
{
}

// Construct a string with latin1 data, from a null-terminated source.
String::String(const LChar* characters)
    : m_impl(characters ? StringImpl::create(characters) : nullptr)
{
}

String::String(const char* characters)
    : m_impl(characters ? StringImpl::create(reinterpret_cast<const LChar*>(characters)) : nullptr)
{
}

void String::append(const String& string)
{
    if (string.isEmpty())
        return;
    if (!m_impl) {
        m_impl = string.m_impl;
        return;
    }

    // FIXME: This is extremely inefficient. So much so that we might want to take this
    // out of String's API. We can make it better by optimizing the case where exactly
    // one String is pointing at this StringImpl, but even then it's going to require a
    // call into the allocator every single time.

    if (m_impl->is8Bit() && string.m_impl->is8Bit()) {
        LChar* data;
        RELEASE_ASSERT(string.length() <= numeric_limits<unsigned>::max() - m_impl->length());
        RefPtr<StringImpl> newImpl = StringImpl::createUninitialized(m_impl->length() + string.length(), data);
        memcpy(data, m_impl->characters8(), m_impl->length() * sizeof(LChar));
        memcpy(data + m_impl->length(), string.characters8(), string.length() * sizeof(LChar));
        m_impl = newImpl.release();
        return;
    }

    UChar* data;
    RELEASE_ASSERT(string.length() <= numeric_limits<unsigned>::max() - m_impl->length());
    RefPtr<StringImpl> newImpl = StringImpl::createUninitialized(m_impl->length() + string.length(), data);

    if (m_impl->is8Bit())
        StringImpl::copyChars(data, m_impl->characters8(), m_impl->length());
    else
        StringImpl::copyChars(data, m_impl->characters16(), m_impl->length());

    if (string.impl()->is8Bit())
        StringImpl::copyChars(data + m_impl->length(), string.impl()->characters8(), string.impl()->length());
    else
        StringImpl::copyChars(data + m_impl->length(), string.impl()->characters16(), string.impl()->length());

    m_impl = newImpl.release();
}

template <typename CharacterType>
inline void String::appendInternal(CharacterType c)
{
    // FIXME: This is extremely inefficient. So much so that we might want to take this
    // out of String's API. We can make it better by optimizing the case where exactly
    // one String is pointing at this StringImpl, but even then it's going to require a
    // call into the allocator every single time.
    if (!m_impl) {
        m_impl = StringImpl::create(&c, 1);
        return;
    }

    UChar* data; // FIXME: We should be able to create an 8 bit string via this code path.
    RELEASE_ASSERT(m_impl->length() < numeric_limits<unsigned>::max());
    RefPtr<StringImpl> newImpl = StringImpl::createUninitialized(m_impl->length() + 1, data);
    if (m_impl->is8Bit())
        StringImpl::copyChars(data, m_impl->characters8(), m_impl->length());
    else
        StringImpl::copyChars(data, m_impl->characters16(), m_impl->length());
    data[m_impl->length()] = c;
    m_impl = newImpl.release();
}

void String::append(LChar c)
{
    appendInternal(c);
}

void String::append(UChar c)
{
    appendInternal(c);
}

int codePointCompare(const String& a, const String& b)
{
    return codePointCompare(a.impl(), b.impl());
}

void String::insert(const String& string, unsigned position)
{
    if (string.isEmpty()) {
        if (string.isNull())
            return;
        if (isNull())
            m_impl = string.impl();
        return;
    }

    if (string.is8Bit())
        insert(string.impl()->characters8(), string.length(), position);
    else
        insert(string.impl()->characters16(), string.length(), position);
}

void String::append(const LChar* charactersToAppend, unsigned lengthToAppend)
{
    if (!m_impl) {
        if (!charactersToAppend)
            return;
        m_impl = StringImpl::create(charactersToAppend, lengthToAppend);
        return;
    }

    if (!lengthToAppend)
        return;

    ASSERT(charactersToAppend);

    unsigned strLength = m_impl->length();

    if (m_impl->is8Bit()) {
        RELEASE_ASSERT(lengthToAppend <= numeric_limits<unsigned>::max() - strLength);
        LChar* data;
        RefPtr<StringImpl> newImpl = StringImpl::createUninitialized(strLength + lengthToAppend, data);
        StringImpl::copyChars(data, m_impl->characters8(), strLength);
        StringImpl::copyChars(data + strLength, charactersToAppend, lengthToAppend);
        m_impl = newImpl.release();
        return;
    }

    RELEASE_ASSERT(lengthToAppend <= numeric_limits<unsigned>::max() - strLength);
    UChar* data;
    RefPtr<StringImpl> newImpl = StringImpl::createUninitialized(length() + lengthToAppend, data);
    StringImpl::copyChars(data, m_impl->characters16(), strLength);
    StringImpl::copyChars(data + strLength, charactersToAppend, lengthToAppend);
    m_impl = newImpl.release();
}

void String::append(const UChar* charactersToAppend, unsigned lengthToAppend)
{
    if (!m_impl) {
        if (!charactersToAppend)
            return;
        m_impl = StringImpl::create(charactersToAppend, lengthToAppend);
        return;
    }

    if (!lengthToAppend)
        return;

    unsigned strLength = m_impl->length();

    ASSERT(charactersToAppend);
    RELEASE_ASSERT(lengthToAppend <= numeric_limits<unsigned>::max() - strLength);
    UChar* data;
    RefPtr<StringImpl> newImpl = StringImpl::createUninitialized(strLength + lengthToAppend, data);
    if (m_impl->is8Bit())
        StringImpl::copyChars(data, characters8(), strLength);
    else
        StringImpl::copyChars(data, characters16(), strLength);
    StringImpl::copyChars(data + strLength, charactersToAppend, lengthToAppend);
    m_impl = newImpl.release();
}

template<typename CharType>
PassRefPtr<StringImpl> insertInternal(PassRefPtr<StringImpl> impl, const CharType* charactersToInsert, unsigned lengthToInsert, unsigned position)
{
    if (!lengthToInsert)
        return impl;

    ASSERT(charactersToInsert);
    UChar* data; // FIXME: We should be able to create an 8 bit string here.
    RELEASE_ASSERT(lengthToInsert <= numeric_limits<unsigned>::max() - impl->length());
    RefPtr<StringImpl> newImpl = StringImpl::createUninitialized(impl->length() + lengthToInsert, data);

    if (impl->is8Bit())
        StringImpl::copyChars(data, impl->characters8(), position);
    else
        StringImpl::copyChars(data, impl->characters16(), position);

    StringImpl::copyChars(data + position, charactersToInsert, lengthToInsert);

    if (impl->is8Bit())
        StringImpl::copyChars(data + position + lengthToInsert, impl->characters8() + position, impl->length() - position);
    else
        StringImpl::copyChars(data + position + lengthToInsert, impl->characters16() + position, impl->length() - position);

    return newImpl.release();
}

void String::insert(const UChar* charactersToInsert, unsigned lengthToInsert, unsigned position)
{
    if (position >= length()) {
        append(charactersToInsert, lengthToInsert);
        return;
    }
    ASSERT(m_impl);
    m_impl = insertInternal(m_impl.release(), charactersToInsert, lengthToInsert, position);
}

void String::insert(const LChar* charactersToInsert, unsigned lengthToInsert, unsigned position)
{
    if (position >= length()) {
        append(charactersToInsert, lengthToInsert);
        return;
    }
    ASSERT(m_impl);
    m_impl = insertInternal(m_impl.release(), charactersToInsert, lengthToInsert, position);
}

UChar32 String::characterStartingAt(unsigned i) const
{
    if (!m_impl || i >= m_impl->length())
        return 0;
    return m_impl->characterStartingAt(i);
}

void String::ensure16Bit()
{
    unsigned length = this->length();
    if (!length || !is8Bit())
        return;
    m_impl = make16BitFrom8BitSource(m_impl->characters8(), length).impl();
}

void String::truncate(unsigned position)
{
    if (position >= length())
        return;
    if (m_impl->is8Bit()) {
        LChar* data;
        RefPtr<StringImpl> newImpl = StringImpl::createUninitialized(position, data);
        memcpy(data, m_impl->characters8(), position * sizeof(LChar));
        m_impl = newImpl.release();
    } else {
        UChar* data;
        RefPtr<StringImpl> newImpl = StringImpl::createUninitialized(position, data);
        memcpy(data, m_impl->characters16(), position * sizeof(UChar));
        m_impl = newImpl.release();
    }
}

template <typename CharacterType>
inline void String::removeInternal(const CharacterType* characters, unsigned position, int lengthToRemove)
{
    CharacterType* data;
    RefPtr<StringImpl> newImpl = StringImpl::createUninitialized(length() - lengthToRemove, data);
    memcpy(data, characters, position * sizeof(CharacterType));
    memcpy(data + position, characters + position + lengthToRemove,
        (length() - lengthToRemove - position) * sizeof(CharacterType));

    m_impl = newImpl.release();
}

void String::remove(unsigned position, int lengthToRemove)
{
    if (lengthToRemove <= 0)
        return;
    if (position >= length())
        return;
    if (static_cast<unsigned>(lengthToRemove) > length() - position)
        lengthToRemove = length() - position;

    if (is8Bit()) {
        removeInternal(characters8(), position, lengthToRemove);

        return;
    }

    removeInternal(characters16(), position, lengthToRemove);
}

String String::substring(unsigned pos, unsigned len) const
{
    if (!m_impl)
        return String();
    return m_impl->substring(pos, len);
}

String String::lower() const
{
    if (!m_impl)
        return String();
    return m_impl->lower();
}

String String::upper() const
{
    if (!m_impl)
        return String();
    return m_impl->upper();
}

String String::lower(const AtomicString& localeIdentifier) const
{
    if (!m_impl)
        return String();
    return m_impl->lower(localeIdentifier);
}

String String::upper(const AtomicString& localeIdentifier) const
{
    if (!m_impl)
        return String();
    return m_impl->upper(localeIdentifier);
}

String String::stripWhiteSpace() const
{
    if (!m_impl)
        return String();
    return m_impl->stripWhiteSpace();
}

String String::stripWhiteSpace(IsWhiteSpaceFunctionPtr isWhiteSpace) const
{
    if (!m_impl)
        return String();
    return m_impl->stripWhiteSpace(isWhiteSpace);
}

String String::simplifyWhiteSpace(StripBehavior stripBehavior) const
{
    if (!m_impl)
        return String();
    return m_impl->simplifyWhiteSpace(stripBehavior);
}

String String::simplifyWhiteSpace(IsWhiteSpaceFunctionPtr isWhiteSpace, StripBehavior stripBehavior) const
{
    if (!m_impl)
        return String();
    return m_impl->simplifyWhiteSpace(isWhiteSpace, stripBehavior);
}

String String::removeCharacters(CharacterMatchFunctionPtr findMatch) const
{
    if (!m_impl)
        return String();
    return m_impl->removeCharacters(findMatch);
}

String String::foldCase() const
{
    if (!m_impl)
        return String();
    return m_impl->foldCase();
}

bool String::percentage(int& result) const
{
    if (!m_impl || !m_impl->length())
        return false;

    if ((*m_impl)[m_impl->length() - 1] != '%')
        return false;

    if (m_impl->is8Bit())
        result = charactersToIntStrict(m_impl->characters8(), m_impl->length() - 1);
    else
        result = charactersToIntStrict(m_impl->characters16(), m_impl->length() - 1);

    return true;
}

Vector<UChar> String::charactersWithNullTermination() const
{
    if (!m_impl)
        return Vector<UChar>();

    Vector<UChar> result;
    result.reserveInitialCapacity(length() + 1);
    appendTo(result);
    result.append(0);
    return result;
}

unsigned String::copyTo(UChar* buffer, unsigned pos, unsigned maxLength) const
{
    unsigned length = this->length();
    RELEASE_ASSERT(pos <= length);
    unsigned numCharacters = std::min(length - pos, maxLength);
    if (!numCharacters)
        return 0;
    if (is8Bit())
        StringImpl::copyChars(buffer, characters8() + pos, numCharacters);
    else
        StringImpl::copyChars(buffer, characters16() + pos, numCharacters);
    return numCharacters;
}

String String::format(const char *format, ...)
{
    va_list args;
    va_start(args, format);

    Vector<char, 256> buffer;

    // Do the format once to get the length.
#if COMPILER(MSVC)
    int result = _vscprintf(format, args);
#else
    char ch;
    int result = vsnprintf(&ch, 1, format, args);
    // We need to call va_end() and then va_start() again here, as the
    // contents of args is undefined after the call to vsnprintf
    // according to http://man.cx/snprintf(3)
    //
    // Not calling va_end/va_start here happens to work on lots of
    // systems, but fails e.g. on 64bit Linux.
    va_end(args);
    va_start(args, format);
#endif

    if (result == 0)
        return String("");
    if (result < 0)
        return String();
    unsigned len = result;
    buffer.grow(len + 1);

    // Now do the formatting again, guaranteed to fit.
    vsnprintf(buffer.data(), buffer.size(), format, args);

    va_end(args);

    return StringImpl::create(reinterpret_cast<const LChar*>(buffer.data()), len);
}

String String::number(int number)
{
    return numberToStringSigned<String>(number);
}

String String::number(unsigned number)
{
    return numberToStringUnsigned<String>(number);
}

String String::number(long number)
{
    return numberToStringSigned<String>(number);
}

String String::number(unsigned long number)
{
    return numberToStringUnsigned<String>(number);
}

String String::number(long long number)
{
    return numberToStringSigned<String>(number);
}

String String::number(unsigned long long number)
{
    return numberToStringUnsigned<String>(number);
}

String String::number(double number, unsigned precision, TrailingZerosTruncatingPolicy trailingZerosTruncatingPolicy)
{
    NumberToStringBuffer buffer;
    return String(numberToFixedPrecisionString(number, precision, buffer, trailingZerosTruncatingPolicy == TruncateTrailingZeros));
}

String String::numberToStringECMAScript(double number)
{
    NumberToStringBuffer buffer;
    return String(numberToString(number, buffer));
}

String String::numberToStringFixedWidth(double number, unsigned decimalPlaces)
{
    NumberToStringBuffer buffer;
    return String(numberToFixedWidthString(number, decimalPlaces, buffer));
}

int String::toIntStrict(bool* ok, int base) const
{
    if (!m_impl) {
        if (ok)
            *ok = false;
        return 0;
    }
    return m_impl->toIntStrict(ok, base);
}

unsigned String::toUIntStrict(bool* ok, int base) const
{
    if (!m_impl) {
        if (ok)
            *ok = false;
        return 0;
    }
    return m_impl->toUIntStrict(ok, base);
}

int64_t String::toInt64Strict(bool* ok, int base) const
{
    if (!m_impl) {
        if (ok)
            *ok = false;
        return 0;
    }
    return m_impl->toInt64Strict(ok, base);
}

uint64_t String::toUInt64Strict(bool* ok, int base) const
{
    if (!m_impl) {
        if (ok)
            *ok = false;
        return 0;
    }
    return m_impl->toUInt64Strict(ok, base);
}

intptr_t String::toIntPtrStrict(bool* ok, int base) const
{
    if (!m_impl) {
        if (ok)
            *ok = false;
        return 0;
    }
    return m_impl->toIntPtrStrict(ok, base);
}

int String::toInt(bool* ok) const
{
    if (!m_impl) {
        if (ok)
            *ok = false;
        return 0;
    }
    return m_impl->toInt(ok);
}

unsigned String::toUInt(bool* ok) const
{
    if (!m_impl) {
        if (ok)
            *ok = false;
        return 0;
    }
    return m_impl->toUInt(ok);
}

int64_t String::toInt64(bool* ok) const
{
    if (!m_impl) {
        if (ok)
            *ok = false;
        return 0;
    }
    return m_impl->toInt64(ok);
}

uint64_t String::toUInt64(bool* ok) const
{
    if (!m_impl) {
        if (ok)
            *ok = false;
        return 0;
    }
    return m_impl->toUInt64(ok);
}

intptr_t String::toIntPtr(bool* ok) const
{
    if (!m_impl) {
        if (ok)
            *ok = false;
        return 0;
    }
    return m_impl->toIntPtr(ok);
}

double String::toDouble(bool* ok) const
{
    if (!m_impl) {
        if (ok)
            *ok = false;
        return 0.0;
    }
    return m_impl->toDouble(ok);
}

float String::toFloat(bool* ok) const
{
    if (!m_impl) {
        if (ok)
            *ok = false;
        return 0.0f;
    }
    return m_impl->toFloat(ok);
}

String String::isolatedCopy() const
{
    if (!m_impl)
        return String();
    return m_impl->isolatedCopy();
}

bool String::isSafeToSendToAnotherThread() const
{
    if (!impl())
        return true;
    if (impl()->isStatic())
        return true;
    // AtomicStrings are not safe to send between threads as ~StringImpl()
    // will try to remove them from the wrong AtomicStringTable.
    if (impl()->isAtomic())
        return false;
    if (impl()->hasOneRef())
        return true;
    return false;
}

void String::split(const String& separator, bool allowEmptyEntries, Vector<String>& result) const
{
    result.clear();

    unsigned startPos = 0;
    size_t endPos;
    while ((endPos = find(separator, startPos)) != kNotFound) {
        if (allowEmptyEntries || startPos != endPos)
            result.append(substring(startPos, endPos - startPos));
        startPos = endPos + separator.length();
    }
    if (allowEmptyEntries || startPos != length())
        result.append(substring(startPos));
}

void String::split(UChar separator, bool allowEmptyEntries, Vector<String>& result) const
{
    result.clear();

    unsigned startPos = 0;
    size_t endPos;
    while ((endPos = find(separator, startPos)) != kNotFound) {
        if (allowEmptyEntries || startPos != endPos)
            result.append(substring(startPos, endPos - startPos));
        startPos = endPos + 1;
    }
    if (allowEmptyEntries || startPos != length())
        result.append(substring(startPos));
}

CString String::ascii() const
{
    // Printable ASCII characters 32..127 and the null character are
    // preserved, characters outside of this range are converted to '?'.

    unsigned length = this->length();
    if (!length) {
        char* characterBuffer;
        return CString::newUninitialized(length, characterBuffer);
    }

    if (this->is8Bit()) {
        const LChar* characters = this->characters8();

        char* characterBuffer;
        CString result = CString::newUninitialized(length, characterBuffer);

        for (unsigned i = 0; i < length; ++i) {
            LChar ch = characters[i];
            characterBuffer[i] = ch && (ch < 0x20 || ch > 0x7f) ? '?' : ch;
        }

        return result;
    }

    const UChar* characters = this->characters16();

    char* characterBuffer;
    CString result = CString::newUninitialized(length, characterBuffer);

    for (unsigned i = 0; i < length; ++i) {
        UChar ch = characters[i];
        characterBuffer[i] = ch && (ch < 0x20 || ch > 0x7f) ? '?' : ch;
    }

    return result;
}

CString String::latin1() const
{
    // Basic Latin1 (ISO) encoding - Unicode characters 0..255 are
    // preserved, characters outside of this range are converted to '?'.

    unsigned length = this->length();

    if (!length)
        return CString("", 0);

    if (is8Bit())
        return CString(reinterpret_cast<const char*>(this->characters8()), length);

    const UChar* characters = this->characters16();

    char* characterBuffer;
    CString result = CString::newUninitialized(length, characterBuffer);

    for (unsigned i = 0; i < length; ++i) {
        UChar ch = characters[i];
        characterBuffer[i] = ch > 0xff ? '?' : ch;
    }

    return result;
}

// Helper to write a three-byte UTF-8 code point to the buffer, caller must check room is available.
static inline void putUTF8Triple(char*& buffer, UChar ch)
{
    ASSERT(ch >= 0x0800);
    *buffer++ = static_cast<char>(((ch >> 12) & 0x0F) | 0xE0);
    *buffer++ = static_cast<char>(((ch >> 6) & 0x3F) | 0x80);
    *buffer++ = static_cast<char>((ch & 0x3F) | 0x80);
}

CString String::utf8(UTF8ConversionMode mode) const
{
    unsigned length = this->length();

    if (!length)
        return CString("", 0);

    // Allocate a buffer big enough to hold all the characters
    // (an individual UTF-16 UChar can only expand to 3 UTF-8 bytes).
    // Optimization ideas, if we find this function is hot:
    //  * We could speculatively create a CStringBuffer to contain 'length'
    //    characters, and resize if necessary (i.e. if the buffer contains
    //    non-ascii characters). (Alternatively, scan the buffer first for
    //    ascii characters, so we know this will be sufficient).
    //  * We could allocate a CStringBuffer with an appropriate size to
    //    have a good chance of being able to write the string into the
    //    buffer without reallocing (say, 1.5 x length).
    if (length > numeric_limits<unsigned>::max() / 3)
        return CString();
    Vector<char, 1024> bufferVector(length * 3);

    char* buffer = bufferVector.data();

    if (is8Bit()) {
        const LChar* characters = this->characters8();

        ConversionResult result = convertLatin1ToUTF8(&characters, characters + length, &buffer, buffer + bufferVector.size());
        ASSERT_UNUSED(result, result != targetExhausted); // (length * 3) should be sufficient for any conversion
    } else {
        const UChar* characters = this->characters16();

        if (mode == StrictUTF8ConversionReplacingUnpairedSurrogatesWithFFFD) {
            const UChar* charactersEnd = characters + length;
            char* bufferEnd = buffer + bufferVector.size();
            while (characters < charactersEnd) {
                // Use strict conversion to detect unpaired surrogates.
                ConversionResult result = convertUTF16ToUTF8(&characters, charactersEnd, &buffer, bufferEnd, true);
                ASSERT(result != targetExhausted);
                // Conversion fails when there is an unpaired surrogate.
                // Put replacement character (U+FFFD) instead of the unpaired surrogate.
                if (result != conversionOK) {
                    ASSERT((0xD800 <= *characters && *characters <= 0xDFFF));
                    // There should be room left, since one UChar hasn't been converted.
                    ASSERT((buffer + 3) <= bufferEnd);
                    putUTF8Triple(buffer, replacementCharacter);
                    ++characters;
                }
            }
        } else {
            bool strict = mode == StrictUTF8Conversion;
            ConversionResult result = convertUTF16ToUTF8(&characters, characters + length, &buffer, buffer + bufferVector.size(), strict);
            ASSERT(result != targetExhausted); // (length * 3) should be sufficient for any conversion

            // Only produced from strict conversion.
            if (result == sourceIllegal) {
                ASSERT(strict);
                return CString();
            }

            // Check for an unconverted high surrogate.
            if (result == sourceExhausted) {
                if (strict)
                    return CString();
                // This should be one unpaired high surrogate. Treat it the same
                // was as an unpaired high surrogate would have been handled in
                // the middle of a string with non-strict conversion - which is
                // to say, simply encode it to UTF-8.
                ASSERT((characters + 1) == (this->characters16() + length));
                ASSERT((*characters >= 0xD800) && (*characters <= 0xDBFF));
                // There should be room left, since one UChar hasn't been converted.
                ASSERT((buffer + 3) <= (buffer + bufferVector.size()));
                putUTF8Triple(buffer, *characters);
            }
        }
    }

    return CString(bufferVector.data(), buffer - bufferVector.data());
}

String String::make8BitFrom16BitSource(const UChar* source, size_t length)
{
    if (!length)
        return String();

    LChar* destination;
    String result = String::createUninitialized(length, destination);

    copyLCharsFromUCharSource(destination, source, length);

    return result;
}

String String::make16BitFrom8BitSource(const LChar* source, size_t length)
{
    if (!length)
        return String();

    UChar* destination;
    String result = String::createUninitialized(length, destination);

    StringImpl::copyChars(destination, source, length);

    return result;
}

String String::fromUTF8(const LChar* stringStart, size_t length)
{
    RELEASE_ASSERT(length <= numeric_limits<unsigned>::max());

    if (!stringStart)
        return String();

    if (!length)
        return emptyString();

    if (charactersAreAllASCII(stringStart, length))
        return StringImpl::create(stringStart, length);

    Vector<UChar, 1024> buffer(length);
    UChar* bufferStart = buffer.data();

    UChar* bufferCurrent = bufferStart;
    const char* stringCurrent = reinterpret_cast<const char*>(stringStart);
    if (convertUTF8ToUTF16(&stringCurrent, reinterpret_cast<const char *>(stringStart + length), &bufferCurrent, bufferCurrent + buffer.size()) != conversionOK)
        return String();

    unsigned utf16Length = bufferCurrent - bufferStart;
    ASSERT(utf16Length < length);
    return StringImpl::create(bufferStart, utf16Length);
}

String String::fromUTF8(const LChar* string)
{
    if (!string)
        return String();
    return fromUTF8(string, strlen(reinterpret_cast<const char*>(string)));
}

String String::fromUTF8(const CString& s)
{
    return fromUTF8(s.data());
}

String String::fromUTF8WithLatin1Fallback(const LChar* string, size_t size)
{
    String utf8 = fromUTF8(string, size);
    if (!utf8)
        return String(string, size);
    return utf8;
}

// String Operations

static bool isCharacterAllowedInBase(UChar c, int base)
{
    if (c > 0x7F)
        return false;
    if (isASCIIDigit(c))
        return c - '0' < base;
    if (isASCIIAlpha(c)) {
        if (base > 36)
            base = 36;
        return (c >= 'a' && c < 'a' + base - 10)
            || (c >= 'A' && c < 'A' + base - 10);
    }
    return false;
}

template <typename IntegralType, typename CharType>
static inline IntegralType toIntegralType(const CharType* data, size_t length, bool* ok, int base)
{
    static const IntegralType integralMax = numeric_limits<IntegralType>::max();
    static const bool isSigned = numeric_limits<IntegralType>::is_signed;
    const IntegralType maxMultiplier = integralMax / base;

    IntegralType value = 0;
    bool isOk = false;
    bool isNegative = false;

    if (!data)
        goto bye;

    // skip leading whitespace
    while (length && isSpaceOrNewline(*data)) {
        --length;
        ++data;
    }

    if (isSigned && length && *data == '-') {
        --length;
        ++data;
        isNegative = true;
    } else if (length && *data == '+') {
        --length;
        ++data;
    }

    if (!length || !isCharacterAllowedInBase(*data, base))
        goto bye;

    while (length && isCharacterAllowedInBase(*data, base)) {
        --length;
        IntegralType digitValue;
        CharType c = *data;
        if (isASCIIDigit(c))
            digitValue = c - '0';
        else if (c >= 'a')
            digitValue = c - 'a' + 10;
        else
            digitValue = c - 'A' + 10;

        if (value > maxMultiplier || (value == maxMultiplier && digitValue > (integralMax % base) + isNegative))
            goto bye;

        value = base * value + digitValue;
        ++data;
    }

#if COMPILER(MSVC)
#pragma warning(push, 0)
#pragma warning(disable:4146)
#endif

    if (isNegative)
        value = -value;

#if COMPILER(MSVC)
#pragma warning(pop)
#endif

    // skip trailing space
    while (length && isSpaceOrNewline(*data)) {
        --length;
        ++data;
    }

    if (!length)
        isOk = true;
bye:
    if (ok)
        *ok = isOk;
    return isOk ? value : 0;
}

template <typename CharType>
static unsigned lengthOfCharactersAsInteger(const CharType* data, size_t length)
{
    size_t i = 0;

    // Allow leading spaces.
    for (; i != length; ++i) {
        if (!isSpaceOrNewline(data[i]))
            break;
    }

    // Allow sign.
    if (i != length && (data[i] == '+' || data[i] == '-'))
        ++i;

    // Allow digits.
    for (; i != length; ++i) {
        if (!isASCIIDigit(data[i]))
            break;
    }

    return i;
}

int charactersToIntStrict(const LChar* data, size_t length, bool* ok, int base)
{
    return toIntegralType<int, LChar>(data, length, ok, base);
}

int charactersToIntStrict(const UChar* data, size_t length, bool* ok, int base)
{
    return toIntegralType<int, UChar>(data, length, ok, base);
}

unsigned charactersToUIntStrict(const LChar* data, size_t length, bool* ok, int base)
{
    return toIntegralType<unsigned, LChar>(data, length, ok, base);
}

unsigned charactersToUIntStrict(const UChar* data, size_t length, bool* ok, int base)
{
    return toIntegralType<unsigned, UChar>(data, length, ok, base);
}

int64_t charactersToInt64Strict(const LChar* data, size_t length, bool* ok, int base)
{
    return toIntegralType<int64_t, LChar>(data, length, ok, base);
}

int64_t charactersToInt64Strict(const UChar* data, size_t length, bool* ok, int base)
{
    return toIntegralType<int64_t, UChar>(data, length, ok, base);
}

uint64_t charactersToUInt64Strict(const LChar* data, size_t length, bool* ok, int base)
{
    return toIntegralType<uint64_t, LChar>(data, length, ok, base);
}

uint64_t charactersToUInt64Strict(const UChar* data, size_t length, bool* ok, int base)
{
    return toIntegralType<uint64_t, UChar>(data, length, ok, base);
}

intptr_t charactersToIntPtrStrict(const LChar* data, size_t length, bool* ok, int base)
{
    return toIntegralType<intptr_t, LChar>(data, length, ok, base);
}

intptr_t charactersToIntPtrStrict(const UChar* data, size_t length, bool* ok, int base)
{
    return toIntegralType<intptr_t, UChar>(data, length, ok, base);
}

int charactersToInt(const LChar* data, size_t length, bool* ok)
{
    return toIntegralType<int, LChar>(data, lengthOfCharactersAsInteger<LChar>(data, length), ok, 10);
}

int charactersToInt(const UChar* data, size_t length, bool* ok)
{
    return toIntegralType<int, UChar>(data, lengthOfCharactersAsInteger(data, length), ok, 10);
}

unsigned charactersToUInt(const LChar* data, size_t length, bool* ok)
{
    return toIntegralType<unsigned, LChar>(data, lengthOfCharactersAsInteger<LChar>(data, length), ok, 10);
}

unsigned charactersToUInt(const UChar* data, size_t length, bool* ok)
{
    return toIntegralType<unsigned, UChar>(data, lengthOfCharactersAsInteger<UChar>(data, length), ok, 10);
}

int64_t charactersToInt64(const LChar* data, size_t length, bool* ok)
{
    return toIntegralType<int64_t, LChar>(data, lengthOfCharactersAsInteger<LChar>(data, length), ok, 10);
}

int64_t charactersToInt64(const UChar* data, size_t length, bool* ok)
{
    return toIntegralType<int64_t, UChar>(data, lengthOfCharactersAsInteger<UChar>(data, length), ok, 10);
}

uint64_t charactersToUInt64(const LChar* data, size_t length, bool* ok)
{
    return toIntegralType<uint64_t, LChar>(data, lengthOfCharactersAsInteger<LChar>(data, length), ok, 10);
}

uint64_t charactersToUInt64(const UChar* data, size_t length, bool* ok)
{
    return toIntegralType<uint64_t, UChar>(data, lengthOfCharactersAsInteger<UChar>(data, length), ok, 10);
}

intptr_t charactersToIntPtr(const LChar* data, size_t length, bool* ok)
{
    return toIntegralType<intptr_t, LChar>(data, lengthOfCharactersAsInteger<LChar>(data, length), ok, 10);
}

intptr_t charactersToIntPtr(const UChar* data, size_t length, bool* ok)
{
    return toIntegralType<intptr_t, UChar>(data, lengthOfCharactersAsInteger<UChar>(data, length), ok, 10);
}

enum TrailingJunkPolicy { DisallowTrailingJunk, AllowTrailingJunk };

template <typename CharType, TrailingJunkPolicy policy>
static inline double toDoubleType(const CharType* data, size_t length, bool* ok, size_t& parsedLength)
{
    size_t leadingSpacesLength = 0;
    while (leadingSpacesLength < length && isASCIISpace(data[leadingSpacesLength]))
        ++leadingSpacesLength;

    double number = parseDouble(data + leadingSpacesLength, length - leadingSpacesLength, parsedLength);
    if (!parsedLength) {
        if (ok)
            *ok = false;
        return 0.0;
    }

    parsedLength += leadingSpacesLength;
    if (ok)
        *ok = policy == AllowTrailingJunk || parsedLength == length;
    return number;
}

double charactersToDouble(const LChar* data, size_t length, bool* ok)
{
    size_t parsedLength;
    return toDoubleType<LChar, DisallowTrailingJunk>(data, length, ok, parsedLength);
}

double charactersToDouble(const UChar* data, size_t length, bool* ok)
{
    size_t parsedLength;
    return toDoubleType<UChar, DisallowTrailingJunk>(data, length, ok, parsedLength);
}

float charactersToFloat(const LChar* data, size_t length, bool* ok)
{
    // FIXME: This will return ok even when the string fits into a double but not a float.
    size_t parsedLength;
    return static_cast<float>(toDoubleType<LChar, DisallowTrailingJunk>(data, length, ok, parsedLength));
}

float charactersToFloat(const UChar* data, size_t length, bool* ok)
{
    // FIXME: This will return ok even when the string fits into a double but not a float.
    size_t parsedLength;
    return static_cast<float>(toDoubleType<UChar, DisallowTrailingJunk>(data, length, ok, parsedLength));
}

float charactersToFloat(const LChar* data, size_t length, size_t& parsedLength)
{
    // FIXME: This will return ok even when the string fits into a double but not a float.
    return static_cast<float>(toDoubleType<LChar, AllowTrailingJunk>(data, length, 0, parsedLength));
}

float charactersToFloat(const UChar* data, size_t length, size_t& parsedLength)
{
    // FIXME: This will return ok even when the string fits into a double but not a float.
    return static_cast<float>(toDoubleType<UChar, AllowTrailingJunk>(data, length, 0, parsedLength));
}

const String& emptyString()
{
    DEFINE_STATIC_LOCAL(String, emptyString, (StringImpl::empty()));
    return emptyString;
}

} // namespace WTF

#ifndef NDEBUG
// For use in the debugger
String* string(const char*);
Vector<char> asciiDebug(StringImpl* impl);
Vector<char> asciiDebug(String& string);

void String::show() const
{
    dataLogF("%s\n", asciiDebug(impl()).data());
}

String* string(const char* s)
{
    // leaks memory!
    return new String(s);
}

Vector<char> asciiDebug(StringImpl* impl)
{
    if (!impl)
        return asciiDebug(String("[null]").impl());

    Vector<char> buffer;
    for (unsigned i = 0; i < impl->length(); ++i) {
        UChar ch = (*impl)[i];
        if (isASCIIPrintable(ch)) {
            if (ch == '\\')
                buffer.append(ch);
            buffer.append(ch);
        } else {
            buffer.append('\\');
            buffer.append('u');
            appendUnsignedAsHexFixedSize(ch, buffer, 4);
        }
    }
    buffer.append('\0');
    return buffer;
}

Vector<char> asciiDebug(String& string)
{
    return asciiDebug(string.impl());
}

#endif
/* [<][>][^][v][top][bottom][index][help] */
root/Source/wtf/text/WTFString.cpp

DEFINITIONS
