PerformanceTests/StitchMarker/wtf/text/CString.cpp

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 *
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 *    notice, this list of conditions and the following disclaimer in the
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#include "config.h"
#include "CString.h"

#include <string.h>
#include <wtf/Hasher.h>

namespace WTF {

Ref<CStringBuffer> CStringBuffer::createUninitialized(size_t length)
{
    RELEASE_ASSERT(length < (std::numeric_limits<unsigned>::max() - sizeof(CStringBuffer)));

    // The +1 is for the terminating null character.
    size_t size = sizeof(CStringBuffer) + length + 1;
    CStringBuffer* stringBuffer = static_cast<CStringBuffer*>(fastMalloc(size));
    return adoptRef(*new (NotNull, stringBuffer) CStringBuffer(length));
}

CString::CString(const char* str)
{
    if (!str)
        return;

    init(str, strlen(str));
}

CString::CString(const char* str, size_t length)
{
    if (!str) {
        ASSERT(!length);
        return;
    }

    init(str, length);
}

void CString::init(const char* str, size_t length)
{
    ASSERT(str);

    m_buffer = CStringBuffer::createUninitialized(length);
    memcpy(m_buffer->mutableData(), str, length); 
    m_buffer->mutableData()[length] = '\0';
}

char* CString::mutableData()
{
    copyBufferIfNeeded();
    if (!m_buffer)
        return 0;
    return m_buffer->mutableData();
}

CString CString::newUninitialized(size_t length, char*& characterBuffer)
{
    CString result;
    result.m_buffer = CStringBuffer::createUninitialized(length);
    char* bytes = result.m_buffer->mutableData();
    bytes[length] = '\0';
    characterBuffer = bytes;
    return result;
}

void CString::copyBufferIfNeeded()
{
    if (!m_buffer || m_buffer->hasOneRef())
        return;

    RefPtr<CStringBuffer> buffer = WTFMove(m_buffer);
    size_t length = buffer->length();
    m_buffer = CStringBuffer::createUninitialized(length);
    memcpy(m_buffer->mutableData(), buffer->data(), length + 1);
}

bool CString::isSafeToSendToAnotherThread() const
{
    return !m_buffer || m_buffer->hasOneRef();
}

bool operator==(const CString& a, const CString& b)
{
    if (a.isNull() != b.isNull())
        return false;
    if (a.length() != b.length())
        return false;
    return !memcmp(a.data(), b.data(), a.length());
}

bool operator==(const CString& a, const char* b)
{
    if (a.isNull() != !b)
        return false;
    if (!b)
        return true;
    return !strcmp(a.data(), b);
}

unsigned CString::hash() const
{
    if (isNull())
        return 0;
    StringHasher hasher;
    for (const char* ptr = data(); *ptr; ++ptr)
        hasher.addCharacter(*ptr);
    return hasher.hash();
}

bool operator<(const CString& a, const CString& b)
{
    if (a.isNull())
        return !b.isNull();
    if (b.isNull())
        return false;
    return strcmp(a.data(), b.data()) < 0;
}

bool CStringHash::equal(const CString& a, const CString& b)
{
    if (a.isHashTableDeletedValue())
        return b.isHashTableDeletedValue();
    if (b.isHashTableDeletedValue())
        return false;
    return a == b;
}

} // namespace WTF