qscriptengine_p.cpp

奇趣公司比较新的qt/emd版本

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#include "qscriptengine_p.h"

#ifndef QT_NO_SCRIPT

#include "qscriptvalueimpl_p.h"
#include "qscriptcontext_p.h"
#include "qscriptmember_p.h"
#include "qscriptobject_p.h"
#include "qscriptlexer_p.h"
#include "qscriptnodepool_p.h"
#include "qscriptparser_p.h"
#include "qscriptcompiler_p.h"
#include "qscriptvalueiterator.h"
#include "qscriptecmaglobal_p.h"
#include "qscriptecmamath_p.h"
#include "qscriptecmaarray_p.h"
#include "qscriptextenumeration_p.h"

#include <QtCore/QDate>
#include <QtCore/QDateTime>
#include <QtCore/QRegExp>
#include <QtCore/QStringList>
#include <QtCore/QVariant>

#ifndef QT_NO_QOBJECT
#include "qscriptextensioninterface.h"
#include <QtCore/QDir>
#include <QtCore/QFile>
#include <QtCore/QFileInfo>
#include <QtCore/QTextStream>
#include <QtCore/QCoreApplication>
#include <QtCore/QPluginLoader>
#endif

Q_DECLARE_METATYPE(QScriptValue)
Q_DECLARE_METATYPE(QVariant)
#ifndef QT_NO_QOBJECT
Q_DECLARE_METATYPE(QObjectList)
#endif
Q_DECLARE_METATYPE(QList<int>)

namespace QScript {

NodePool::~NodePool()
{
    qDeleteAll(m_codeCache);
    m_codeCache.clear();
}

Code *NodePool::createCompiledCode(AST::Node *node, CompilationUnit &compilation)
{
    QHash<AST::Node*, Code*>::const_iterator it = m_codeCache.constFind(node);
    if (it != m_codeCache.constEnd())
        return it.value();

    Code *code = new Code();
    code->init(compilation, this);

    m_codeCache.insert(node, code);
    return code;
}

class EvalFunction : public QScriptFunction
{
public:
    EvalFunction(QScriptEnginePrivate *)
    { length = 1; }

    virtual ~EvalFunction() {}

    void evaluate(QScriptContextPrivate *context, const QString &contents,
                  int lineNo, const QString &fileName, bool calledFromScript)
    {
        QScriptEngine *engine = context->engine();
        QScriptEnginePrivate *eng_p = QScriptEnginePrivate::get(engine);

        QExplicitlySharedDataPointer<NodePool> pool;
        pool = new NodePool(fileName);
        eng_p->setNodePool(pool);

        AST::Node *program = eng_p->createAbstractSyntaxTree(contents, lineNo);

        eng_p->setNodePool(0);

        if (! program) {
            context->errorLineNumber = lineNo;
            context->currentLine = lineNo;
            context->throwError(QScriptContext::SyntaxError, eng_p->errorMessage());
            return;
        }

        Compiler compiler(engine);
        compiler.setTopLevelCompiler(true);
        CompilationUnit compilation = compiler.compile(program);
        if (! compilation.isValid()) {
            context->throwError(compilation.errorMessage());
            return;
        }

        Code *code = pool->createCompiledCode(program, compilation);

        if (calledFromScript) {
            if (QScriptContext *parentContext = context->parentContext()) {
                QScriptContextPrivate *pc_p = QScriptContextPrivate::get(parentContext);
                context->setActivationObject(pc_p->activationObject());
                context->setThisObject(pc_p->thisObject());
            }
        }

        const QScriptInstruction *iPtr = context->instructionPointer();
        context->execute(code);
        context->setInstructionPointer(iPtr);
    }

    virtual void execute(QScriptContextPrivate *context)
    {
        QScriptEnginePrivate *eng = QScriptEnginePrivate::get(context->engine());
        int lineNo = context->currentLine;
        QString fileName; // don't set this for now, we don't want to change the official eval() for now.

        if (context->argumentCount() == 0) {
            context->setReturnValue(eng->undefinedValue());
        } else {
            QScriptValueImpl arg = context->argument(0);
            if (arg.isString()) {
                QString contents = arg.toString();
                evaluate(context, contents, lineNo, fileName, /*calledFromScript=*/true);
            } else {
                context->setReturnValue(arg);
            }
        }
    }
};

class WithClassData: public QScriptClassData
{

public:
    virtual bool resolve(const QScriptValueImpl &object, QScriptNameIdImpl *nameId,
                         QScript::Member *member, QScriptValueImpl *base);
};

bool WithClassData::resolve(const QScriptValueImpl &object, QScriptNameIdImpl *nameId,
                            QScript::Member *member, QScriptValueImpl *base)
{
    QScriptValueImpl proto = object.prototype();
    Q_ASSERT(proto.isValid());
    Q_ASSERT(proto.isObject());
    return proto.resolve(nameId, member, base, QScriptValue::ResolveScope);
}


class ArgumentsClassData: public QScriptClassData
{

public:

    static inline QScript::ArgumentsObjectData *get(const QScriptValueImpl &object)
        { return static_cast<QScript::ArgumentsObjectData*>(object.objectData().data()); }

    virtual bool resolve(const QScriptValueImpl &object, QScriptNameIdImpl *nameId,
                         QScript::Member *member, QScriptValueImpl *base);
    virtual bool get(const QScriptValueImpl &object, const QScript::Member &member,
                     QScriptValueImpl *out_value);
    virtual bool put(QScriptValueImpl *object, const QScript::Member &member,
                     const QScriptValueImpl &value);
    virtual void mark(const QScriptValueImpl &object, int generation);
};

bool ArgumentsClassData::resolve(const QScriptValueImpl &object, QScriptNameIdImpl *nameId,
                                 QScript::Member *member, QScriptValueImpl *base)
{
    QScriptEnginePrivate *eng_p = QScriptEnginePrivate::get(object.engine());

    if (nameId == eng_p->idTable()->id_length) {
        member->native(nameId, /*id=*/ 0,
                       QScriptValue::Undeletable
                       | QScriptValue::ReadOnly);
        *base = object;
        return true;
    } else if (nameId == eng_p->idTable()->id_callee) {
        member->native(nameId, /*id=*/ 0,
                       QScriptValue::Undeletable
                       | QScriptValue::ReadOnly);
        *base = object;
        return true;
    }

    QString propertyName = eng_p->toString(nameId);
    bool isNumber;
    quint32 index = propertyName.toUInt(&isNumber);
    if (isNumber) {
        QScript::ArgumentsObjectData *data = ArgumentsClassData::get(object);
        if (index < data->length) {
            member->native(/*nameId=*/0, index, 0);
            *base = object;
            return true;
        }
    }

    return false;
}

bool ArgumentsClassData::get(const QScriptValueImpl &object, const QScript::Member &member,
                             QScriptValueImpl *out_value)
{
    QScriptEnginePrivate *eng_p = QScriptEnginePrivate::get(object.engine());
    QScript::ArgumentsObjectData *data = ArgumentsClassData::get(object);
    if (member.nameId() == 0) {
        QScriptObject *activation_data = data->activation.objectValue();
        *out_value = activation_data->m_objects[member.id()];
        return true;
    } else if (member.nameId() == eng_p->idTable()->id_length) {
        eng_p->newNumber(out_value, data->length);
        return true;
    } else if (member.nameId() == eng_p->idTable()->id_callee) {
        *out_value = data->callee;
        return true;
    }
    return false;
}

bool ArgumentsClassData::put(QScriptValueImpl *object, const QScript::Member &member,
                             const QScriptValueImpl &value)
{
    Q_ASSERT(member.nameId() == 0);
    QScript::ArgumentsObjectData *data = ArgumentsClassData::get(*object);
    QScriptObject *activation_data = data->activation.objectValue();
    activation_data->m_objects[member.id()] = value;
    return true;
}

void ArgumentsClassData::mark(const QScriptValueImpl &object, int generation)
{
    QScript::ArgumentsObjectData *data = ArgumentsClassData::get(object);
    data->activation.mark(generation);
    data->callee.mark(generation);
}

} // namespace QScript

const qsreal QScriptEnginePrivate::D16 = 65536.0;
const qsreal QScriptEnginePrivate::D32 = 4294967296.0;

QScriptEnginePrivate::~QScriptEnginePrivate()
{
    // invalidate values that we have references to
    {
        QHash<QScriptObject*, QScriptValuePrivate*>::const_iterator it;
        for (it = m_objectHandles.constBegin(); it != m_objectHandles.constEnd(); ++it)
            (*it)->value.invalidate();
    }
    {
        QHash<QScriptNameIdImpl*, QScriptValuePrivate*>::const_iterator it;
        for (it = m_stringHandles.constBegin(); it != m_stringHandles.constEnd(); ++it)
            (*it)->value.invalidate();
    }
    {
        QVector<QScriptValuePrivate*>::const_iterator it;
        for (it = m_otherHandles.constBegin(); it != m_otherHandles.constEnd(); ++it)
            (*it)->value.invalidate();
    }

    delete[] m_string_hash_base;
    qDeleteAll(m_stringRepository);
    qDeleteAll(m_tempStringRepository);

    delete[] tempStackBegin;

#ifndef QT_NO_QOBJECT
# ifndef Q_SCRIPT_NO_QMETAOBJECT_CACHE
    qDeleteAll(m_cachedMetaObjects);
# endif
#endif

    qDeleteAll(m_allocated_classes);
}

QScript::AST::Node *QScriptEnginePrivate::changeAbstractSyntaxTree(QScript::AST::Node *prg)
{
    QScript::AST::Node *was = m_abstractSyntaxTree;
    m_abstractSyntaxTree = prg;
    return was;
}

QScript::AST::Node *QScriptEnginePrivate::createAbstractSyntaxTree(const QString &source, int &lineNumber)
{
    m_errorMessage.clear();

    QScript::Lexer lex(q_func());
    setLexer(&lex);
    lex.setCode(source, lineNumber);

    QScriptParser parser;

    if (! parser.parse(this)) {
        m_errorMessage = parser.errorMessage();
        lineNumber = parser.errorLineNumber();
        return 0;
    }

    return abstractSyntaxTree();
}

void QScriptEnginePrivate::markObject(const QScriptValueImpl &object, int generation)
{
    QScriptObject *instance = object.objectValue();
    QScript::GCBlock *block = QScript::GCBlock::get(instance);

    enum { MAX_GC_DEPTH = 32 };

    if (block->generation + 1 != generation)
        return;

    if (m_gc_depth >= MAX_GC_DEPTH) {
        // do the marking later
        m_markStack.append(object);
        return;
    }

    ++block->generation;
    ++m_gc_depth;