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#include "qscriptdebuggerbackend_p.h"

#include "qscriptdebuggerbackend_p_p.h"

#include "qscriptdebuggeragent_p.h"

#include "qscriptdebuggercommandexecutor_p.h"

#include "qscriptdebuggerevent_p.h"

#include "qscriptdebuggervalue_p.h"

#include "qscriptscriptdata_p.h"

#include "qscriptbreakpointdata_p.h"

#include "qscriptobjectsnapshot_p.h"

#include <QtScript/qscriptengine.h>

#include <QtScript/qscriptcontextinfo.h>

#include <QtScript/qscriptvalueiterator.h>

#include <QtCore/qcoreapplication.h>

#include <QtCore/qdebug.h>

Q_DECLARE_METATYPE(QScriptDebuggerValue)

Q_DECLARE_METATYPE(QScriptDebuggerBackendPrivate*)

QT_BEGIN_NAMESPACE

/*!

  \since 4.5

  \class QScriptDebuggerBackend

  \internal

  \brief The QScriptDebuggerBackend class is the base class of debugger back-ends.

  QScriptDebuggerBackend builds on the QScriptDebuggerAgent class.

  This class is usually used together with the QScriptDebuggerFrontend

  class, in order to form a (front-end, back-end) pair.

  Call attachTo() to attach to a QScriptEngine object. Call detach()

  to detach from the current engine.

  Call stepInto() to step into the next script statement; call stepOver()

  to step over the next script statement; and call stepOut() to step out

  of the currently executing script function. An event() will be generated

  when the stepping is completed.

  Call runToLocation() to execute script statements until a certain

  location has been reached. An event() will be generated when the location

  has been reached.

  Call interruptEvaluation() to request that evaluation should be

  interrupted. An event() will be generated upon the next script

  statement that is reached.

  Call continueEvalution() to allow script evaluation to continue.

  Call setBreakpoint() to set a breakpoint. A breakpoint event() will

  be generated when a breakpoint is hit. Call deleteBreakpoint() to

  delete a breakpoint. Call modifyBreakpoint() to change the state of

  an existing breakpoint.

  Call contextCount() to obtain the number of active contexts

  (frames). Call context() to obtain a pointer to a QScriptContext.

  \section1 Subclassing

  When subclassing QScriptDebuggerBackend, you must implement the pure

  virtual event() function. This function typically forwards the event

  to a QScriptDebuggerFrontend object. For most type of events,

  event() should block until the back-end is instructed to resume

  execution (e.g. until continueEvalution() is called). You must

  implement resume(), which is responsible for making event() return.

  \sa QScriptDebuggerFrontend, QScriptDebuggerEvent

*/

// helper class that's used to handle our custom Qt events

class QScriptDebuggerBackendEventReceiver : public QObject

{

public:

    QScriptDebuggerBackendEventReceiver(QScriptDebuggerBackendPrivate *backend,

                                        QObject *parent = 0)

        : QObject(parent), m_backend(backend) {}

    ~QScriptDebuggerBackendEventReceiver() {}

    bool event(QEvent *e)

    {

        return m_backend->event(e);

    }

private:

    QScriptDebuggerBackendPrivate *m_backend;

};

QScriptDebuggerBackendPrivate::QScriptDebuggerBackendPrivate()

    : agent(0), commandExecutor(0),

        pendingEvaluateContextIndex(-1), pendingEvaluateLineNumber(-1),

        ignoreExceptions(false),

        nextScriptValueIteratorId(0), nextScriptObjectSnapshotId(0),

        eventReceiver(0),

        q_ptr(0) // q_ptr will be set later by QScriptDebuggerBackend constructor

{

}

QScriptDebuggerBackendPrivate::~QScriptDebuggerBackendPrivate()

{

    if (agent)

        agent->nullifyBackendPointer();

    delete commandExecutor;

    delete eventReceiver;

    qDeleteAll(scriptValueIterators);

    qDeleteAll(scriptObjectSnapshots);

}

void QScriptDebuggerBackendPrivate::postEvent(QEvent *e)

{

    if (!eventReceiver) {

        eventReceiver = new QScriptDebuggerBackendEventReceiver(this);

        eventReceiver->moveToThread(agent->engine()->thread());

    }

    QCoreApplication::postEvent(eventReceiver, e);

}

bool QScriptDebuggerBackendPrivate::event(QEvent *e)

{

    if (e->type() == QEvent::User+1) {

        QScriptDebuggerEventEvent *de = static_cast<QScriptDebuggerEventEvent*>(e);

        q_func()->event(de->event());

        return true;

    }

    return false;

}

void QScriptDebuggerBackendPrivate::agentDestroyed(QScriptDebuggerAgent *ag)

{

    // Since agents are owned by the script engine, this in practice means

    // that the engine has been destroyed. Invalidate our pointer so we

    // don't crash later.

    if (agent == ag)

        agent = 0;

}

/*!

  The agent calls this function when it has completed a step

  operation.

*/

void QScriptDebuggerBackendPrivate::stepped(qint64 scriptId,

                                            int lineNumber,

                                            int columnNumber,

                                            const QScriptValue &result)

{

    Q_Q(QScriptDebuggerBackend);

    QScriptDebuggerEvent e(QScriptDebuggerEvent::SteppingFinished,

                           scriptId, lineNumber, columnNumber);

    e.setFileName(agent->scriptData(scriptId).fileName());

    QScriptDebuggerValue value(result);

    e.setScriptValue(value);

    if (!result.isUndefined())

        e.setMessage(result.toString()); // for convenience -- we always need it

    q->event(e);

}

/*!

  The agent calls this function when it has run to a particular

  location.

*/

void QScriptDebuggerBackendPrivate::locationReached(qint64 scriptId,

                                                    int lineNumber,

                                                    int columnNumber)

{

    Q_Q(QScriptDebuggerBackend);

    QScriptDebuggerEvent e(QScriptDebuggerEvent::LocationReached,

                           scriptId, lineNumber, columnNumber);

    e.setFileName(agent->scriptData(scriptId).fileName());

    q->event(e);

}

/*!

  The agent calls this function when evaluation has been interrupted.

*/

void QScriptDebuggerBackendPrivate::interrupted(qint64 scriptId,

                                                int lineNumber,

                                                int columnNumber)

{

    Q_Q(QScriptDebuggerBackend);

    QScriptDebuggerEvent e(QScriptDebuggerEvent::Interrupted,

                           scriptId, lineNumber, columnNumber);

    e.setFileName(agent->scriptData(scriptId).fileName());

    q->event(e);

}

/*!

  The agent calls this function when a breakpoint has been triggered.

*/

void QScriptDebuggerBackendPrivate::breakpoint(qint64 scriptId,

                                               int lineNumber,

                                               int columnNumber,

                                               int breakpointId)

{

    Q_Q(QScriptDebuggerBackend);

    QScriptDebuggerEvent e(QScriptDebuggerEvent::Breakpoint,

                           scriptId, lineNumber, columnNumber);

    e.setFileName(agent->scriptData(scriptId).fileName());

    e.setBreakpointId(breakpointId);

    q->event(e);

}

/*!

  The agent calls this function when an uncaught exception has

  occurred.

*/

void QScriptDebuggerBackendPrivate::exception(qint64 scriptId,

                                              const QScriptValue &exception,

                                              bool hasHandler)

{

    Q_Q(QScriptDebuggerBackend);

    if (ignoreExceptions) {

        // don't care (it's caught by us)

        return;

    }

    QScriptDebuggerEvent e(QScriptDebuggerEvent::Exception);

    e.setScriptId(scriptId);

    e.setFileName(agent->scriptData(scriptId).fileName());

    e.setMessage(exception.toString());

    e.setHasExceptionHandler(hasHandler);

    int lineNumber = -1;

    QString fileName;

    if (exception.property(QLatin1String("lineNumber")).isNumber())

        lineNumber = exception.property(QLatin1String("lineNumber")).toInt32();

    if (exception.property(QLatin1String("fileName")).isString())

        fileName = exception.property(QLatin1String("fileName")).toString();

    if (lineNumber == -1) {

        QScriptContextInfo info(q->engine()->currentContext());

        lineNumber = info.lineNumber();

        fileName = info.fileName();

    }

    if (lineNumber != -1)

        e.setLineNumber(lineNumber);

    if (!fileName.isEmpty())

        e.setFileName(fileName);

    QScriptDebuggerValue value(exception);

    e.setScriptValue(value);

    q->event(e);

}

QScriptValue QScriptDebuggerBackendPrivate::trace(QScriptContext *context,

                                                  QScriptEngine *engine)

{

    QScriptValue data = context->callee().data();

    QScriptDebuggerBackendPrivate *self = qscriptvalue_cast<QScriptDebuggerBackendPrivate*>(data);

    if (!self)

        return engine->undefinedValue();

    QString str;

    for (int i = 0; i < context->argumentCount(); ++i) {

        if (i > 0)

            str.append(QLatin1Char(' '));

        str.append(context->argument(i).toString());

    }

    QScriptDebuggerEvent e(QScriptDebuggerEvent::Trace);

    e.setMessage(str);

    self->q_func()->event(e);

    return engine->undefinedValue();

}

QScriptValue QScriptDebuggerBackendPrivate::qsassert(QScriptContext *context,

                                                     QScriptEngine *engine)

{

    QScriptValue arg = context->argument(0);

    if (arg.toBoolean())

        return arg;

    QScriptContextInfo info(context->parentContext());

    QString msg;

    QString fileName = info.fileName();

    if (fileName.isEmpty())

        fileName = QString::fromLatin1("<anonymous script, id=%0>").arg(info.scriptId());

    msg.append(fileName);

    msg.append(QLatin1Char(':'));

    msg.append(QString::number(info.lineNumber()));

    msg.append(QString::fromLatin1(": Assertion failed"));

    for (int i = 1; i < context->argumentCount(); ++i) {

        if (i == 1)

            msg.append(QLatin1Char(':'));

        msg.append(QLatin1Char(' '));

        msg.append(context->argument(i).toString());

    }

    QScriptValue err = context->throwError(msg);

    err.setProperty(QString::fromLatin1("name"), QScriptValue(engine, QString::fromLatin1("AssertionError")));

    return err;

}

QScriptValue QScriptDebuggerBackendPrivate::fileName(QScriptContext *context,

                                                     QScriptEngine *engine)

{

    QScriptContextInfo info(context->parentContext());

    QString fn = info.fileName();

    if (fn.isEmpty())

        return engine->undefinedValue();

    return QScriptValue(engine, fn);

}

QScriptValue QScriptDebuggerBackendPrivate::lineNumber(QScriptContext *context,

                                                       QScriptEngine *engine)

{

    QScriptContextInfo info(context->parentContext());

    return QScriptValue(engine, info.lineNumber());

}

/*!

  The agent calls this function when the engine has reached a

  "debugger" statement.

*/

void QScriptDebuggerBackendPrivate::debuggerInvocationRequest(

    qint64 scriptId, int lineNumber, int columnNumber)

{

    Q_Q(QScriptDebuggerBackend);

    QScriptDebuggerEvent e(QScriptDebuggerEvent::DebuggerInvocationRequest,

                           scriptId, lineNumber, columnNumber);

    e.setFileName(agent->scriptData(scriptId).fileName());

    q->event(e);

}

void QScriptDebuggerBackendPrivate::forcedReturn(

    qint64 scriptId, int lineNumber, int columnNumber,

    const QScriptValue &value)

{

    Q_Q(QScriptDebuggerBackend);

    QScriptDebuggerEvent e(QScriptDebuggerEvent::ForcedReturn,

                           scriptId, lineNumber, columnNumber);

    e.setFileName(agent->scriptData(scriptId).fileName());

    e.setScriptValue(QScriptDebuggerValue(value));

    q->event(e);

}

/*!

  Creates a QScriptDebuggerBackend object.

*/

QScriptDebuggerBackend::QScriptDebuggerBackend()

    : d_ptr(new QScriptDebuggerBackendPrivate)

{

    d_ptr->q_ptr = this;

}

/*!

  Destroys this QScriptDebuggerBackend.

*/

QScriptDebuggerBackend::~QScriptDebuggerBackend()

{

    detach();

}

/*!

  \internal

*/

QScriptDebuggerBackend::QScriptDebuggerBackend(QScriptDebuggerBackendPrivate &dd)

    : d_ptr(&dd)

{

    d_ptr->q_ptr = this;

}

/*!

  Attaches this backend to the given \a engine.

  The backend automatically detaches from the old engine, if any.

  This function installs its own agent on the \a engine using

  QScriptEngine::setAgent(); any existing agent will be replaced.

  \sa detach(). engine()

*/

void QScriptDebuggerBackend::attachTo(QScriptEngine *engine)

{

    Q_D(QScriptDebuggerBackend);

    detach();

    d->agent = new QScriptDebuggerAgent(d, engine);

    QScriptValue global = engine->globalObject();

    d->origTraceFunction = global.property(QString::fromLatin1("print"));

    global.setProperty(QString::fromLatin1("print"), traceFunction());

//    global.setProperty(QString::fromLatin1("qAssert"), assertFunction());

    d->origFileNameFunction = global.property(QString::fromLatin1("__FILE__"));

    global.setProperty(QString::fromLatin1("__FILE__"), fileNameFunction(),

                       QScriptValue::PropertyGetter | QScriptValue::ReadOnly);

    d->origLineNumberFunction = global.property(QString::fromLatin1("__LINE__"));

    global.setProperty(QString::fromLatin1("__LINE__"), lineNumberFunction(),

                       QScriptValue::PropertyGetter | QScriptValue::ReadOnly);

    engine->setAgent(d->agent);

}

/*!

  Detaches this backend from the current script engine.

  The backend's state (including breakpoints and information on loaded

  scripts) will be invalidated.

  \sa attach()

*/

void QScriptDebuggerBackend::detach()

{

    Q_D(QScriptDebuggerBackend);

    if (d->agent) {

        QScriptEngine *eng = d->agent->engine();

        if (eng && eng->agent() == d->agent) {

            eng->setAgent(0);

            QScriptValue global = eng->globalObject();

            global.setProperty(QString::fromLatin1("print"), d->origTraceFunction);

            d->origTraceFunction = QScriptValue();

//            global.setProperty(QString::fromLatin1("qAssert"), QScriptValue());

            global.setProperty(QString::fromLatin1("__FILE__"), QScriptValue(),

                               QScriptValue::PropertyGetter);

            global.setProperty(QString::fromLatin1("__FILE__"), d->origFileNameFunction);

            d->origFileNameFunction = QScriptValue();

            global.setProperty(QString::fromLatin1("__LINE__"), QScriptValue(),

                               QScriptValue::PropertyGetter);

            global.setProperty(QString::fromLatin1("__LINE__"), d->origLineNumberFunction);

            d->origLineNumberFunction = QScriptValue();

            d->agent->nullifyBackendPointer();

            d->agent = 0; // agent is owned by engine

        }

    }

    d->pendingEvaluateLineNumber = -1;

    d->ignoreExceptions = false;

    d->nextScriptValueIteratorId = 0;

    qDeleteAll(d->scriptValueIterators);

    d->scriptValueIterators.clear();

    qDeleteAll(d->scriptObjectSnapshots);

    d->scriptObjectSnapshots.clear();

}

/*!

  Returns the script engine that this backend is attached to, or 0 if

  the backend is not attached to an engine.

  \sa attachTo()

*/

QScriptEngine *QScriptDebuggerBackend::engine() const

{

    Q_D(const QScriptDebuggerBackend);

    if (!d->agent)

        return 0;

    return d->agent->engine();

}

/*!

  Steps into the next script statement.

  When stepping is complete, an event() will be generated.

*/

void QScriptDebuggerBackend::stepInto(int count)

{

    Q_D(QScriptDebuggerBackend);

    if (d->agent) {

        d->agent->enterStepIntoMode(count);

        resume();

    }

}

/*!

  Steps over the next script statement.

  When stepping is complete, an event() will be generated.

*/

void QScriptDebuggerBackend::stepOver(int count)

{

    Q_D(QScriptDebuggerBackend);

    if (d->agent) {

        d->agent->enterStepOverMode(count);

        resume();

    }

}

/*!

  Steps out of the current script function.

  When stepping is complete, an event() will be generated.

*/

void QScriptDebuggerBackend::stepOut()

{

    Q_D(QScriptDebuggerBackend);

    if (d->agent) {

        d->agent->enterStepOutMode();

        resume();

    }

}

/*!

  Continues script evaluation. Evaluation will proceed without

  interruption until either 1) an uncaught exception occurs, 2) a

  breakpoint is triggered, or 3) interruptEvaluation() is called.

  In each case, a proper event() will be generated.

*/

void QScriptDebuggerBackend::continueEvalution()

{

    Q_D(QScriptDebuggerBackend);

    if (d->agent) {

        d->agent->enterContinueMode();