string.cpp

linux下开源浏览器WebKit的源码,市面上的很多商用浏览器都是移植自WebKit

{
    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);
}

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);
}

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

bool String::isEmpty() const
{
    return !m_impl || !m_impl->length();
}

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

    int startPos = 0;
    int endPos;
    while ((endPos = find(separator, startPos)) != -1) {
        if (allowEmptyEntries || startPos != endPos)
            result.append(substring(startPos, endPos - startPos));
        startPos = endPos + separator.length();
    }
    if (allowEmptyEntries || startPos != static_cast<int>(length()))
        result.append(substring(startPos));
}

void String::split(const String& separator, Vector<String>& result) const
{
    return split(separator, false, result);
}

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

    int startPos = 0;
    int endPos;
    while ((endPos = find(separator, startPos)) != -1) {
        if (allowEmptyEntries || startPos != endPos)
            result.append(substring(startPos, endPos - startPos));
        startPos = endPos + 1;
    }
    if (allowEmptyEntries || startPos != static_cast<int>(length()))
        result.append(substring(startPos));
}

void String::split(UChar separator, Vector<String>& result) const
{
    return split(String(&separator, 1), false, result);
}

#ifndef NDEBUG
Vector<char> String::ascii() const
{
    if (m_impl) 
        return m_impl->ascii();
    
    const char* nullMsg = "(null impl)";
    Vector<char, 2048> buffer;
    for (int i = 0; nullMsg[i]; ++i)
        buffer.append(nullMsg[i]);
    
    buffer.append('\0');
    return buffer;
}
#endif

CString String::latin1() const
{
    return Latin1Encoding().encode(characters(), length(), QuestionMarksForUnencodables);
}
    
CString String::utf8() const
{
    return UTF8Encoding().encode(characters(), length(), QuestionMarksForUnencodables);
}

String String::fromUTF8(const char* string, size_t size)
{
    if (!string)
        return String();
    return UTF8Encoding().decode(string, size);
}

String String::fromUTF8(const char* string)
{
    if (!string)
        return String();
    return UTF8Encoding().decode(string, strlen(string));
}

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

#if USE(JSC)
String::String(const Identifier& str)
{
    if (str.isNull())
        return;
    m_impl = StringImpl::create(str.data(), str.size());
}

String::String(const UString& str)
{
    if (str.isNull())
        return;
    m_impl = StringImpl::create(str.data(), str.size());
}

String::operator UString() const
{
    if (!m_impl)
        return UString();
    return UString(m_impl->characters(), m_impl->length());
}
#endif

// 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>
static inline IntegralType toIntegralType(const UChar* data, size_t length, bool* ok, int base)
{
    static const IntegralType integralMax = std::numeric_limits<IntegralType>::max();
    static const bool isSigned = std::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;
        UChar 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;
}

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

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

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

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

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

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

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

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

double charactersToDouble(const UChar* data, size_t length, bool* ok)
{
    if (!length) {
        if (ok)
            *ok = false;
        return 0.0;
    }

    Vector<char, 256> bytes(length + 1);
    for (unsigned i = 0; i < length; ++i)
        bytes[i] = data[i] < 0x7F ? data[i] : '?';
    bytes[length] = '\0';
    char* end;
    double val = WTF::strtod(bytes.data(), &end);
    if (ok)
        *ok = (end == 0 || *end == '\0');
    return val;
}

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.
    return narrowPrecisionToFloat(charactersToDouble(data, length, ok));
}

PassRefPtr<SharedBuffer> utf8Buffer(const String& string)
{
    // Allocate a buffer big enough to hold all the characters.
    const int length = string.length();
    Vector<char> buffer(length * 3);

    // Convert to runs of 8-bit characters.
    char* p = buffer.data();
    const UChar* d = string.characters();
    ConversionResult result = convertUTF16ToUTF8(&d, d + length, &p, p + buffer.size(), true);
    if (result != conversionOK)
        return 0;

    buffer.shrink(p - buffer.data());
    return SharedBuffer::adoptVector(buffer);
}

} // namespace WebCore

#ifndef NDEBUG
// For use in the debugger - leaks memory
WebCore::String* string(const char*);

WebCore::String* string(const char* s)
{
    return new WebCore::String(s);
}
#endif