qdbusintegrator.cpp

QT 开发环境里面一个很重要的文件

/****************************************************************************
**
** Copyright (C) 1992-2006 Trolltech ASA. All rights reserved.
**
** This file is part of the tools applications of the Qt Toolkit.
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** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
** this file.  Please review the following information to ensure GNU
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** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
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#include <qcoreapplication.h>
#include <qcoreevent.h>
#include <qdebug.h>
#include <qmetaobject.h>
#include <qobject.h>
#include <qsocketnotifier.h>
#include <qstringlist.h>
#include <qtimer.h>

#include "qdbusargument.h"
#include "qdbusconnection_p.h"
#include "qdbusinterface_p.h"
#include "qdbusmessage.h"
#include "qdbusmetatype.h"
#include "qdbusmetatype_p.h"
#include "qdbusabstractadaptor.h"
#include "qdbusabstractadaptor_p.h"
#include "qdbusutil_p.h"
#include "qdbusmessage_p.h"

static bool isDebugging;
#define qDBusDebug              if (!::isDebugging); else qDebug

#ifndef USE_OUTSIDE_DISPATCH
# define USE_OUTSIDE_DISPATCH    0
#endif

typedef void (*QDBusSpyHook)(const QDBusMessage&);
typedef QVarLengthArray<QDBusSpyHook, 4> QDBusSpyHookList;
Q_GLOBAL_STATIC(QDBusSpyHookList, qDBusSpyHookList)

Q_GLOBAL_STATIC(QStringList, qDBusServicesRegisteredByThread)

struct QDBusPendingCall
{
    QPointer<QObject> receiver;
    QList<int> metaTypes;
    int methodIdx;
    DBusPendingCall *pending;
    const QDBusConnectionPrivate *connection;
};

class CallDeliveryEvent: public QEvent
{
public:
    CallDeliveryEvent()
        : QEvent(QEvent::User), object(0), flags(0), slotIdx(-1)
        { }

    const QDBusConnectionPrivate *conn;
    QPointer<QObject> object;
    QDBusMessage message;
    QList<int> metaTypes;

    int flags;
    int slotIdx;
};

static dbus_bool_t qDBusAddTimeout(DBusTimeout *timeout, void *data)
{
    Q_ASSERT(timeout);
    Q_ASSERT(data);

  //  qDebug("addTimeout %d", dbus_timeout_get_interval(timeout));

    QDBusConnectionPrivate *d = static_cast<QDBusConnectionPrivate *>(data);

    if (!dbus_timeout_get_enabled(timeout))
        return true;

    if (!QCoreApplication::instance()) {
        d->pendingTimeouts.append(timeout);
        return true;
    }
    int timerId = d->startTimer(dbus_timeout_get_interval(timeout));
    if (!timerId)
        return false;

    d->timeouts[timerId] = timeout;
    return true;
}

static void qDBusRemoveTimeout(DBusTimeout *timeout, void *data)
{
    Q_ASSERT(timeout);
    Q_ASSERT(data);

  //  qDebug("removeTimeout");

    QDBusConnectionPrivate *d = static_cast<QDBusConnectionPrivate *>(data);
    d->pendingTimeouts.removeAll(timeout);

    QDBusConnectionPrivate::TimeoutHash::iterator it = d->timeouts.begin();
    while (it != d->timeouts.end()) {
        if (it.value() == timeout) {
            d->killTimer(it.key());
            it = d->timeouts.erase(it);
        } else {
            ++it;
        }
    }
}

static void qDBusToggleTimeout(DBusTimeout *timeout, void *data)
{
    Q_ASSERT(timeout);
    Q_ASSERT(data);

    //qDebug("ToggleTimeout");

    qDBusRemoveTimeout(timeout, data);
    qDBusAddTimeout(timeout, data);
}

static dbus_bool_t qDBusAddWatch(DBusWatch *watch, void *data)
{
    Q_ASSERT(watch);
    Q_ASSERT(data);

    QDBusConnectionPrivate *d = static_cast<QDBusConnectionPrivate *>(data);

    int flags = dbus_watch_get_flags(watch);
    int fd = dbus_watch_get_fd(watch);

    QDBusConnectionPrivate::Watcher watcher;
    if (flags & DBUS_WATCH_READABLE) {
        //qDebug("addReadWatch %d", fd);
        watcher.watch = watch;
        if (QCoreApplication::instance()) {
            watcher.read = new QSocketNotifier(fd, QSocketNotifier::Read, d);
            watcher.read->setEnabled(dbus_watch_get_enabled(watch));
            d->connect(watcher.read, SIGNAL(activated(int)), SLOT(socketRead(int)));
        }
    }
    if (flags & DBUS_WATCH_WRITABLE) {
        //qDebug("addWriteWatch %d", fd);
        watcher.watch = watch;
        if (QCoreApplication::instance()) {
            watcher.write = new QSocketNotifier(fd, QSocketNotifier::Write, d);
            watcher.write->setEnabled(dbus_watch_get_enabled(watch));
            d->connect(watcher.write, SIGNAL(activated(int)), SLOT(socketWrite(int)));
        }
    }
    d->watchers.insertMulti(fd, watcher);

    return true;
}

static void qDBusRemoveWatch(DBusWatch *watch, void *data)
{
    Q_ASSERT(watch);
    Q_ASSERT(data);

    //qDebug("remove watch");

    QDBusConnectionPrivate *d = static_cast<QDBusConnectionPrivate *>(data);
    int fd = dbus_watch_get_fd(watch);

    QDBusConnectionPrivate::WatcherHash::iterator i = d->watchers.find(fd);
    while (i != d->watchers.end() && i.key() == fd) {
        if (i.value().watch == watch) {
            delete i.value().read;
            delete i.value().write;
            d->watchers.erase(i);
            return;
        }
        ++i;
    }
}

static void qDBusToggleWatch(DBusWatch *watch, void *data)
{
    Q_ASSERT(watch);
    Q_ASSERT(data);

    QDBusConnectionPrivate *d = static_cast<QDBusConnectionPrivate *>(data);
    int fd = dbus_watch_get_fd(watch);

    QDBusConnectionPrivate::WatcherHash::iterator i = d->watchers.find(fd);
    while (i != d->watchers.end() && i.key() == fd) {
        if (i.value().watch == watch) {
            bool enabled = dbus_watch_get_enabled(watch);
            int flags = dbus_watch_get_flags(watch);

            //qDebug("toggle watch %d to %d (write: %d, read: %d)", dbus_watch_get_fd(watch), enabled, flags & DBUS_WATCH_WRITABLE, flags & DBUS_WATCH_READABLE);

            if (flags & DBUS_WATCH_READABLE && i.value().read)
                i.value().read->setEnabled(enabled);
            if (flags & DBUS_WATCH_WRITABLE && i.value().write)
                i.value().write->setEnabled(enabled);
            return;
        }
        ++i;
    }
}

static void qDBusNewConnection(DBusServer *server, DBusConnection *c, void *data)
{
    Q_ASSERT(data); Q_ASSERT(server); Q_ASSERT(c);
    Q_UNUSED(data); Q_UNUSED(server); Q_UNUSED(c);

    qDebug("SERVER: GOT A NEW CONNECTION"); // TODO
}

extern QDBUS_EXPORT void qDBusAddSpyHook(QDBusSpyHook);
void qDBusAddSpyHook(QDBusSpyHook hook)
{
    qDBusSpyHookList()->append(hook);
}

#if USE_OUTSIDE_DISPATCH
# define HANDLED     DBUS_HANDLER_RESULT_HANDLED_OUTSIDE_DISPATCH
static DBusHandlerResult qDBusSignalFilterOutside(DBusConnection *connection,
                                                  DBusMessage *message, void *data)
{
    Q_ASSERT(data);
    Q_UNUSED(connection);
    Q_UNUSED(message);

    QDBusConnectionPrivate *d = static_cast<QDBusConnectionPrivate *>(data);
    if (d->mode == QDBusConnectionPrivate::InvalidMode)
        return DBUS_HANDLER_RESULT_NOT_YET_HANDLED; // internal error, actually

    CallDeliveryEvent *e = d->postedCallDeliveryEvent();

    d->deliverCall(*e);
    delete e;

    return DBUS_HANDLER_RESULT_HANDLED;
}
#else
# define HANDLED     DBUS_HANDLER_RESULT_HANDLED
#endif

extern "C" {
static DBusHandlerResult
qDBusSignalFilter(DBusConnection *connection, DBusMessage *message, void *data)
{
    return QDBusConnectionPrivate::messageFilter(connection, message, data);
}
}

DBusHandlerResult QDBusConnectionPrivate::messageFilter(DBusConnection *connection,
                                                        DBusMessage *message, void *data)
{
    Q_ASSERT(data);
    Q_UNUSED(connection);

    QDBusConnectionPrivate *d = static_cast<QDBusConnectionPrivate *>(data);
    if (d->mode == QDBusConnectionPrivate::InvalidMode)
        return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;

    QDBusMessage amsg = QDBusMessagePrivate::fromDBusMessage(message);
    qDBusDebug() << "got message:" << amsg;

    const QDBusSpyHookList *list = qDBusSpyHookList();
    for (int i = 0; i < list->size(); ++i) {
        qDBusDebug() << "calling the message spy hook";
        (*(*list)[i])(amsg);
    }

    bool handled = false;
    int msgType = dbus_message_get_type(message);
    if (msgType == DBUS_MESSAGE_TYPE_SIGNAL) {
        handled = d->handleSignal(amsg);
    } else if (msgType == DBUS_MESSAGE_TYPE_METHOD_CALL) {
        handled = d->handleObjectCall(amsg);
    }

    return handled ? HANDLED :
        DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
}

static void huntAndDestroy(QObject *needle, QDBusConnectionPrivate::ObjectTreeNode *haystack)
{
    QDBusConnectionPrivate::ObjectTreeNode::DataList::ConstIterator it = haystack->children.constBegin();
    QDBusConnectionPrivate::ObjectTreeNode::DataList::ConstIterator end = haystack->children.constEnd();
    for ( ; it != end; ++it)
        huntAndDestroy(needle, it->node);

    if (needle == haystack->obj) {
        haystack->obj = 0;
        haystack->flags = 0;
    }
}

static void huntAndEmit(DBusConnection *connection, DBusMessage *msg,
                        QObject *needle, QDBusConnectionPrivate::ObjectTreeNode *haystack,
                        bool isScriptable, bool isAdaptor, const QString &path = QString())
{
    QDBusConnectionPrivate::ObjectTreeNode::DataList::ConstIterator it = haystack->children.constBegin();
    QDBusConnectionPrivate::ObjectTreeNode::DataList::ConstIterator end = haystack->children.constEnd();
    for ( ; it != end; ++it)
        huntAndEmit(connection, msg, needle, it->node, isScriptable, isAdaptor, path + QLatin1String("/") + it->name);

    if (needle == haystack->obj) {
        // is this a signal we should relay?
        if (isAdaptor && (haystack->flags & QDBusConnection::ExportAdaptors) == 0)
            return;             // no: it comes from an adaptor and we're not exporting adaptors
        else if (!isAdaptor) {
            int mask = isScriptable
                       ? QDBusConnection::ExportScriptableSignals
                       : QDBusConnection::ExportNonScriptableSignals;
            if ((haystack->flags & mask) == 0)
                return;         // signal was not exported
        }

        QByteArray p = path.toLatin1();
        if (p.isEmpty())
            p = "/";
        qDBusDebug() << "Emitting signal at " << p;
        DBusMessage *msg2 = dbus_message_copy(msg);
        dbus_message_set_path(msg2, p);
        dbus_connection_send(connection, msg2, 0);
        dbus_message_unref(msg2);
    }
}

static int findSlot(const QMetaObject *mo, const QByteArray &name, int flags,
                    const QString &signature_, QList<int>& metaTypes)
{
    QByteArray msgSignature = signature_.toLatin1();

    for (int idx = mo->methodCount() - 1 ; idx >= QObject::staticMetaObject.methodCount(); --idx) {
        QMetaMethod mm = mo->method(idx);

        // check access:
        if (mm.access() != QMetaMethod::Public)
            continue;

        // check type:
        // unnecessary, since signals are never public:
        //if (mm.methodType() != QMetaMethod::Slot)
        //    continue;

        // check name:
        QByteArray slotname = mm.signature();
        int paren = slotname.indexOf('(');
        if (paren != name.length() || !slotname.startsWith(name))
            continue;

        int returnType = qDBusNameToTypeId(mm.typeName());
        bool isAsync = qDBusCheckAsyncTag(mm.tag());
        bool isScriptable = mm.attributes() & QMetaMethod::Scriptable;

        // consistency check:
        if (isAsync && returnType != QMetaType::Void)
            continue;

        int inputCount = qDBusParametersForMethod(mm, metaTypes);
        if (inputCount == -1)
            continue;           // problem parsing

        metaTypes[0] = returnType;
        bool hasMessage = false;
        if (inputCount > 0 &&
            metaTypes.at(inputCount) == QDBusMetaTypeId::message) {
            // "no input parameters" is allowed as long as the message meta type is there
            hasMessage = true;
            --inputCount;
        }

        // try to match the parameters
        int i;
        QByteArray reconstructedSignature;
        for (i = 1; i <= inputCount; ++i) {
            const char *typeSignature = QDBusMetaType::typeToSignature( metaTypes.at(i) );
            if (!typeSignature)
                break;          // invalid

            reconstructedSignature += typeSignature;
            if (!msgSignature.startsWith(reconstructedSignature))
                break;
        }

        if (reconstructedSignature != msgSignature)
            continue;           // we didn't match them all

        if (hasMessage)
            ++i;

        // make sure that the output parameters have signatures too
        if (returnType != 0 && QDBusMetaType::typeToSignature(returnType) == 0)
            continue;

        bool ok = true;
        for (int j = i; ok && j < metaTypes.count(); ++j)
            if (QDBusMetaType::typeToSignature(metaTypes.at(i)) == 0)
                ok = false;
        if (!ok)
            continue;

        // consistency check:
        if (isAsync && metaTypes.count() > i + 1)
            continue;

        if (isScriptable && (flags & QDBusConnection::ExportScriptableSlots) == 0)
            continue;           // not exported
        if (!isScriptable && (flags & QDBusConnection::ExportNonScriptableSlots) == 0)
            continue;           // not exported

        // if we got here, this slot matched
        return idx;
    }

    // no slot matched
    return -1;