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** Copyright (C) 2016 The Qt Company Ltd.
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** This file is part of the QtQml module of the Qt Toolkit.
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** packaging of this file. Please review the following information to
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#include "qv4compileddata_p.h"
#include <private/qv4staticvalue_p.h>
#include <private/qqmlirbuilder_p.h>
#include <QCoreApplication>
#include <QCryptographicHash>
#include <QSaveFile>
#include <QScopeGuard>
#include <QFileInfo>

// generated by qmake:
#include "qml_compile_hash_p.h"

#include <algorithm>

QT_BEGIN_NAMESPACE

namespace QV4 {

namespace CompiledData {

#if defined(QML_COMPILE_HASH)
#  ifdef Q_OS_LINUX
// Place on a separate section on Linux so it's easier to check from outside
// what the hash version is.
__attribute__((section(".qml_compile_hash")))
#  endif
const char qml_compile_hash[48 + 1] = QML_COMPILE_HASH;
static_assert(sizeof(Unit::libraryVersionHash) >= QML_COMPILE_HASH_LENGTH + 1, "Compile hash length exceeds reserved size in data structure. Please adjust and bump the format version");
#else
#  error "QML_COMPILE_HASH must be defined for the build of QtDeclarative to ensure version checking for cache files"
#endif


CompilationUnit::CompilationUnit(const Unit *unitData, const QString &fileName, const QString &finalUrlString)
{
    setUnitData(unitData, nullptr, fileName, finalUrlString);
}

CompilationUnit::~CompilationUnit()
{
    if (data) {
        if (data->qmlUnit() != qmlData)
            free(const_cast<QmlUnit *>(qmlData));
        qmlData = nullptr;

        if (!(data->flags & QV4::CompiledData::Unit::StaticData))
            free(const_cast<Unit *>(data));
    }
    data = nullptr;
#if Q_BYTE_ORDER == Q_BIG_ENDIAN
    delete [] constants;
    constants = nullptr;
#endif

    delete [] imports;
    imports = nullptr;
}

bool CompilationUnit::saveToDisk(const QString &outputFileName, QString *errorString) const
{
    errorString->clear();

#if QT_CONFIG(temporaryfile)
    // Foo.qml -> Foo.qmlc
    QSaveFile cacheFile(outputFileName);
    if (!cacheFile.open(QIODevice::WriteOnly | QIODevice::Truncate)) {
        *errorString = cacheFile.errorString();
        return false;
    }

    SaveableUnitPointer saveable(this);
    qint64 headerWritten = cacheFile.write(saveable.data<char>(), saveable.size());
    if (headerWritten != saveable.size()) {
        *errorString = cacheFile.errorString();
        return false;
    }

    if (!cacheFile.commit()) {
        *errorString = cacheFile.errorString();
        return false;
    }

    return true;
#else
    Q_UNUSED(outputFileName)
    *errorString = QStringLiteral("features.temporaryfile is disabled.");
    return false;
#endif // QT_CONFIG(temporaryfile)
}

void CompilationUnit::setUnitData(const Unit *unitData, const QmlUnit *qmlUnit,
                                  const QString &fileName, const QString &finalUrlString)
{
    data = unitData;
    qmlData = nullptr;
#if Q_BYTE_ORDER == Q_BIG_ENDIAN
    delete [] constants;
#endif
    constants = nullptr;
    m_fileName.clear();
    m_finalUrlString.clear();
    if (!data)
        return;

    qmlData = qmlUnit ? qmlUnit : data->qmlUnit();

#if Q_BYTE_ORDER == Q_BIG_ENDIAN
    StaticValue *bigEndianConstants = new StaticValue[data->constantTableSize];
    const quint64_le *littleEndianConstants = data->constants();
    for (uint i = 0; i < data->constantTableSize; ++i)
        bigEndianConstants[i] = StaticValue::fromReturnedValue(littleEndianConstants[i]);
    constants = bigEndianConstants;
#else
    constants = reinterpret_cast<const StaticValue*>(data->constants());
#endif

    m_fileName = !fileName.isEmpty() ? fileName : stringAt(data->sourceFileIndex);
    m_finalUrlString = !finalUrlString.isEmpty() ? finalUrlString : stringAt(data->finalUrlIndex);
}

//reverse of Lexer::singleEscape()
QString Binding::escapedString(const QString &string)
{
    QString tmp = QLatin1String("\"");
    for (int i = 0; i < string.length(); ++i) {
        const QChar &c = string.at(i);
        switch (c.unicode()) {
        case 0x08:
            tmp += QLatin1String("\\b");
            break;
        case 0x09:
            tmp += QLatin1String("\\t");
            break;
        case 0x0A:
            tmp += QLatin1String("\\n");
            break;
        case 0x0B:
            tmp += QLatin1String("\\v");
            break;
        case 0x0C:
            tmp += QLatin1String("\\f");
            break;
        case 0x0D:
            tmp += QLatin1String("\\r");
            break;
        case 0x22:
            tmp += QLatin1String("\\\"");
            break;
        case 0x27:
            tmp += QLatin1String("\\\'");
            break;
        case 0x5C:
            tmp += QLatin1String("\\\\");
            break;
        default:
            tmp += c;
            break;
        }
    }
    tmp += QLatin1Char('\"');
    return tmp;
}

void CompilationUnit::unlink()
{
    free(runtimeStrings);
    runtimeStrings = nullptr;
    delete [] runtimeRegularExpressions;
    runtimeRegularExpressions = nullptr;
    free(runtimeClasses);
    runtimeClasses = nullptr;
}

void Unit::generateChecksum()
{
#ifndef QT_CRYPTOGRAPHICHASH_ONLY_SHA1
    QCryptographicHash hash(QCryptographicHash::Md5);

    const int checksummableDataOffset = offsetof(QV4::CompiledData::Unit, md5Checksum) + sizeof(md5Checksum);

    const char *dataPtr = reinterpret_cast<const char *>(this) + checksummableDataOffset;
    hash.addData(dataPtr, unitSize - checksummableDataOffset);

    QByteArray checksum = hash.result();
    Q_ASSERT(checksum.size() == sizeof(md5Checksum));
    memcpy(md5Checksum, checksum.constData(), sizeof(md5Checksum));
#else
    memset(md5Checksum, 0, sizeof(md5Checksum));
#endif
}

bool Unit::verifyHeader(QDateTime expectedSourceTimeStamp, QString *errorString) const
{
    if (strncmp(magic, CompiledData::magic_str, sizeof(magic))) {
        *errorString = QStringLiteral("Magic bytes in the header do not match");
        return false;
    }

    if (version != quint32(QV4_DATA_STRUCTURE_VERSION)) {
        *errorString = QString::fromUtf8("V4 data structure version mismatch. Found %1 expected %2").arg(version, 0, 16).arg(QV4_DATA_STRUCTURE_VERSION, 0, 16);
        return false;
    }

    if (qtVersion != quint32(QT_VERSION)) {
        *errorString = QString::fromUtf8("Qt version mismatch. Found %1 expected %2").arg(qtVersion, 0, 16).arg(QT_VERSION, 0, 16);
        return false;
    }

    if (sourceTimeStamp) {
        // Files from the resource system do not have any time stamps, so fall back to the application
        // executable.
        if (!expectedSourceTimeStamp.isValid())
            expectedSourceTimeStamp = QFileInfo(QCoreApplication::applicationFilePath()).lastModified();

        if (expectedSourceTimeStamp.isValid() && expectedSourceTimeStamp.toMSecsSinceEpoch() != sourceTimeStamp) {
            *errorString = QStringLiteral("QML source file has a different time stamp than cached file.");
            return false;
        }
    }

#if defined(QML_COMPILE_HASH)
    if (qstrcmp(CompiledData::qml_compile_hash, libraryVersionHash) != 0) {
        *errorString = QStringLiteral("QML library version mismatch. Expected compile hash does not match");
        return false;
    }
#else
#error "QML_COMPILE_HASH must be defined for the build of QtDeclarative to ensure version checking for cache files"
#endif

    return true;
}

}

}

QT_END_NAMESPACE