File indexing completed on 2024-05-12 17:15:12

 /*
    Copyright (C) 2013 Andreas Hartmetz <ahartmetz@gmail.com>
 
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.
 
    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.
 
    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LGPL.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
 
    Alternatively, this file is available under the Mozilla Public License
    Version 1.1.  You may obtain a copy of the License at
    http://www.mozilla.org/MPL/
 */
 
 #include "eavesdroppermodel.h"
 
 #include "arguments.h"
 #include "message.h"
 
 #include <QDataStream>
 #include <QFile>
 
 enum {
     TypeColumn = 0,
     RoundtripTimeColumn,
     MethodColumn,
     InterfaceColumn,
     PathColumn,
     SenderColumn,
     DestinationColumn,
     ColumnCount
 };
 
 MessageRecord::MessageRecord(Message *msg, qint64 time)
    : message(msg),
      otherMessageIndex(-1),
      timestamp(time)
 {}
 
 MessageRecord::MessageRecord()
    : message(nullptr),
      otherMessageIndex(-1),
      timestamp(-1)
 {}
 
 QString MessageRecord::type() const
 {
     switch (message->type()) {
     case Message::MethodCallMessage:
         return QObject::tr("Call");
     case Message::MethodReturnMessage:
         return QObject::tr("Return");
     case Message::ErrorMessage:
         return QObject::tr("Error");
     case Message::SignalMessage:
         return QObject::tr("Signal");
     case Message::InvalidMessage:
         return QString::fromLatin1("???");
     }
     Q_ASSERT(false);
     return QString();
 }
 
 bool MessageRecord::isAwaitingReply() const
 {
     return message->type() == Message::MethodCallMessage &&
            message->expectsReply() && otherMessageIndex < 0;
 }
 
 bool MessageRecord::isReplyToKnownCall() const
 {
     return otherMessageIndex >= 0 && (message->type() == Message::MethodReturnMessage ||
                                       message->type() == Message::ErrorMessage);
 }
 
 uint32 MessageRecord::conversationSerial() const
 {
     if (message->type() == Message::MethodReturnMessage || message->type() == Message::ErrorMessage) {
         return message->replySerial();
     }
     return message->serial();
 }
 
 QString MessageRecord::conversationMethod(const std::vector<MessageRecord> &container) const
 {
     std::string method;
     if (isReplyToKnownCall()) {
         method = container[otherMessageIndex].message->method();
     } else {
         method = message->method();
     }
     return QString::fromStdString(method);
 }
 
 qint64 MessageRecord::conversationStartTime(const std::vector<MessageRecord> &container) const
 {
     if (isReplyToKnownCall()) {
         return container[otherMessageIndex].timestamp;
     }
     return timestamp;
 }
 
 qint64 MessageRecord::roundtripTime(const std::vector<MessageRecord> &container) const
 {
     if (isReplyToKnownCall()) {
         return timestamp - container[otherMessageIndex].timestamp;
     }
     return -1;
 }
 
 static bool isNumericAddress(const std::string &address)
 {
     return !address.empty() && address[0] == ':';
 }
 
 QString MessageRecord::niceSender(const std::vector<MessageRecord> &container) const
 {
     // this does something like ":1.2" -> ":1.2 (org.freedesktop.fooInterface)"
     std::string sender = message->sender();
     if (isNumericAddress(sender) && isReplyToKnownCall()) {
         const std::string otherDest = container[otherMessageIndex].message->destination();
         if (!otherDest.empty() && otherDest[0] != ':') {
             sender += " (";
             sender += otherDest;
             sender += ')';
         }
     }
     return QString::fromStdString(sender);
 }
 
 bool MessageRecord::couldHaveNicerDestination(const std::vector<MessageRecord> &container) const
 {
     // see niceDestination; this returns true if the "raw" destination is *not* of the :n.m type
     // and the other (i.e. reply) message's sender *is* o the :n.m type
     if (message->type() != Message::MethodCallMessage || otherMessageIndex < 0) {
         return false;
     }
     const std::string dest = message->destination();
     if (isNumericAddress(dest)) {
         return false;
     }
     const std::string otherSender = container[otherMessageIndex].message->sender();
     return !otherSender.empty() && otherSender[0] == ':';
 }
 
 QString MessageRecord::niceDestination(const std::vector<MessageRecord> &container) const
 {
     // this does something like "org.freedesktop.fooInterface" -> "org.freedesktop.fooInterface (:1.2)"
     std::string dest = message->destination();
     if (couldHaveNicerDestination(container)) {
         dest += " (";
         dest += container[otherMessageIndex].message->sender();
         dest += ')';
     }
     return QString::fromStdString(dest);
 }
 
 EavesdropperModel::EavesdropperModel(QObject *parent)
    : QAbstractItemModel(parent),
      m_worker(this),
      m_isRecording(true)
 {
 }
 
 EavesdropperModel::~EavesdropperModel()
 {
     clearInternal();
 }
 
 void EavesdropperModel::addMessage(Message *message, qint64 timestamp)
 {
     if (!m_isRecording) {
         return;
     }
     beginInsertRows(QModelIndex(), m_messages.size(), m_messages.size());
     m_messages.push_back(MessageRecord(message, timestamp));
 
     const uint currentMessageIndex = m_messages.size() - 1;
 
     // Connect responses with previously spotted calls because information from one is useful for the other.
     // We must match the call sender with the reply receiver, instead of the call receiver with the reply
     // sender, because calls can go to well-known addresses that are only resolved to a concrete endpoint
     // by the bus daemon.
 
     if (message->type() == Message::MethodCallMessage) {
         // the NO_REPLY_EXPECTED flag does *not* forbid a reply, so we disregard the flag
         // ### it would be nice to clean up m_callsAwaitingResponse periodically, but we allocate
         //     memory that is not freed before shutdown left and right so it doesn't make much of
         //     a difference. it does make a difference when serials overflow.
         m_callsAwaitingResponse[Call(message->serial(), message->sender())] = currentMessageIndex;
     } else if (message->type() == Message::MethodReturnMessage || message->type() == Message::ErrorMessage) {
         Call key(message->replySerial(), message->destination());
         std::map<Call, uint32>::iterator it = m_callsAwaitingResponse.find(key);
         // we could have missed the initial call because it happened before we connected to the bus...
         // theoretically we could assert the presence of the call after one d-bus timeout has passed
         if (it != m_callsAwaitingResponse.end()) {
             const uint originalMessageIndex = it->second;
             m_messages.back().otherMessageIndex = originalMessageIndex;
             m_messages[originalMessageIndex].otherMessageIndex = currentMessageIndex;
             m_callsAwaitingResponse.erase(it);
             if (m_messages[originalMessageIndex].couldHaveNicerDestination(m_messages)) {
                 const QModelIndex index = createIndex(originalMessageIndex, DestinationColumn);
                 emit dataChanged(index, index);
             }
         }
     }
     endInsertRows();
 }
 
 QVariant EavesdropperModel::data(const QModelIndex &index, int role) const
 {
     if (role == Qt::DisplayRole) {
         Q_ASSERT(size_t(index.row()) < m_messages.size());
         const MessageRecord &mr = m_messages[index.row()];
         switch (index.column()) {
         case TypeColumn:
             return mr.type();
         case RoundtripTimeColumn: {
             qint64 rtt = mr.roundtripTime(m_messages);
             Q_ASSERT(rtt >= -1); // QElapsedTimer should give us monotonic time
             if (rtt == -1) {
                 break;  // no data for a message that doesn't or can't have a reply
             }
             return static_cast<double>(rtt) / 1000000.0; // nsecs / 1E6 -> milliseconds
         }
         case MethodColumn:
             return mr.conversationMethod(m_messages);
         case InterfaceColumn:
             return QString::fromStdString(mr.message->interface());
         case PathColumn:
             return QString::fromStdString(mr.message->path());
         case SenderColumn:
             return mr.niceSender(m_messages);
         case DestinationColumn:
             return mr.niceDestination(m_messages);
         default:
             break;
         }
     }
     return QVariant();
 }
 
 QVariant EavesdropperModel::headerData(int section, Qt::Orientation orientation, int role) const
 {
     if (role == Qt::DisplayRole && orientation == Qt::Horizontal) {
         switch (section) {
         case TypeColumn:
             return tr("Type");
         case RoundtripTimeColumn:
             return tr("Latency [ms]");
         case MethodColumn:
             return tr("Method");
         case InterfaceColumn:
             return tr("Interface");
         case PathColumn:
             return tr("Path");
         case SenderColumn:
             return tr("Sender");
         case DestinationColumn:
             return tr("Destination");
         default:
             break;
         }
     }
     return QVariant();
 }
 
 QModelIndex EavesdropperModel::index(int row, int column, const QModelIndex &parent) const
 {
     if (parent.isValid()) {
         Q_ASSERT(parent.model() == this);
         return QModelIndex();
     }
     return createIndex(row, column);
 }
 
 bool EavesdropperModel::hasChildren (const QModelIndex &parent) const
 {
     return !parent.isValid();
 }
 
 QModelIndex EavesdropperModel::parent(const QModelIndex &child) const
 {
     Q_ASSERT(!child.isValid() || child.model() == this); // ### why does it crash with &&?
     Q_UNUSED(child);
     return QModelIndex();
 }
 
 int EavesdropperModel::rowCount(const QModelIndex &/* parent */) const
 {
     return m_messages.size();
 }
 
 int EavesdropperModel::columnCount(const QModelIndex &/* parent */) const
 {
     return ColumnCount;
 }
 
 void EavesdropperModel::setRecording(bool recording)
 {
     // We could stop the eavesdropper thread when not recording, but it doesn't seem worth the effort.
     m_isRecording = recording;
 }
 
 void EavesdropperModel::clear()
 {
     beginResetModel();
     clearInternal();
     endResetModel();
 }
 
 void EavesdropperModel::clearInternal()
 {
     m_callsAwaitingResponse.clear();
     // This is easier than making MessageRecord clean up after itself - it would need refcounting in order
     // to avoid accidentally deleting the message in many common situations.
     for (MessageRecord &msgRecord : m_messages) {
         delete msgRecord.message;
         msgRecord.message = nullptr;
     }
     m_messages.clear();
 }
 
 // TODO make the header 32 (or 16) bytes long in the next version - right now, the alignment doesn't
 // make a big difference because message data is copied at least once, but still - would be cleaner.
 static const char *fileHeader = "Dferry binary DBus dump v0001";
 
 void EavesdropperModel::saveToFile(const QString &path)
 {
     QFile file(path);
     file.open(QIODevice::WriteOnly | QIODevice::Truncate);
     file.write(fileHeader);
 
     for (MessageRecord &msgRecord : m_messages) {
         std::vector<byte> msgData = msgRecord.message->save();
 
         // auxiliary data from MessageRecord, length prefix
         {
             QDataStream auxStream(&file);
             auxStream.setVersion(12);
             auxStream << msgRecord.otherMessageIndex;
             auxStream << msgRecord.timestamp;
             auxStream << quint32(msgData.size());
         }
 
         // serialized message just like it would appear on the bus
         file.write(reinterpret_cast<const char*>(&msgData[0]), msgData.size());
     }
 }
 
 bool EavesdropperModel::loadFromFile(const QString &path)
 {
     QFile file(path);
     file.open(QIODevice::ReadOnly);
     if (file.read(strlen(fileHeader)) != QByteArray(fileHeader)) {
         return false;
     }
 
     std::vector<MessageRecord> loadedRecords;
     while (!file.atEnd()) {
         MessageRecord record;
         quint32 messageDataSize;
         // auxiliary data from MessageRecord, length prefix
         {
             QDataStream auxStream(&file);
             auxStream.setVersion(12);
             auxStream >> record.otherMessageIndex;
             auxStream >> record.timestamp;
             auxStream >> messageDataSize;
         }
         if (file.atEnd()) {
             return false;
         }
 
         // serialized message just like it would appear on the bus
         chunk msgBuf;
         msgBuf.length = messageDataSize;
         msgBuf.ptr = reinterpret_cast<byte *>(malloc(msgBuf.length));
         if (file.read(reinterpret_cast<char*>(msgBuf.ptr), messageDataSize) != messageDataSize) {
             return false;
         }
         record.message = new Message();
         record.message->deserializeAndTake(msgBuf);
 
         loadedRecords.push_back(record);
     }
 
     beginResetModel();
     clearInternal();
     m_messages = loadedRecords;
     endResetModel();
     // TODO disable capture or make sure that our call-reply matching features work in the
     //      presence of data loaded from a different session...
     return true;
 }