Save log to file and always save e2ee debug logs

This will hopefully help us debug e2ee problems

src/CMakeLists.txt

@@ -48,6 +48,7 @@ add_library(neochat STATIC
     filetransferpseudojob.cpp
     models/searchmodel.cpp
     texthandler.cpp
+    logger.cpp
 )
 
 add_executable(neochat-app

src/logger.cpp

@@ -0,0 +1,208 @@
+// SPDX-FileCopyrightText: 1997 Matthias Kalle Dalheimer <kalle@kde.org>
+// SPDX-FileCopyrightText: 2002 Holger Freyther <freyther@kde.org>
+// SPDX-FileCopyrightText: 2008 Volker Krause <vkrause@kde.org>
+// SPDX-FileCopyrightText: 2023 Tobias Fella <fella@posteo.de>
+// SPDX-License-Identifier: LGPL-2.0-or-later
+
+#include "logger.h"
+
+#include <QDateTime>
+#include <QDir>
+#include <QFileInfo>
+#include <QLoggingCategory>
+#include <QMutex>
+#include <QStandardPaths>
+
+static QLoggingCategory::CategoryFilter oldCategoryFilter = nullptr;
+static QtMessageHandler oldHandler = nullptr;
+static bool e2eeDebugEnabled = false;
+
+class FileDebugStream : public QIODevice
+{
+    Q_OBJECT
+public:
+    FileDebugStream()
+        : mType(QtCriticalMsg)
+    {
+        open(WriteOnly);
+    }
+
+    bool isSequential() const override
+    {
+        return true;
+    }
+    qint64 readData(char *, qint64) override
+    {
+        return 0;
+    }
+    qint64 readLineData(char *, qint64) override
+    {
+        return 0;
+    }
+
+    qint64 writeData(const char *data, qint64 len) override
+    {
+        if (!mFileName.isEmpty()) {
+            QFile outputFile(mFileName);
+            outputFile.open(QIODevice::WriteOnly | QIODevice::Append | QIODevice::Unbuffered);
+            outputFile.write(data, len);
+            outputFile.putChar('\n');
+            outputFile.close();
+        }
+
+        return len;
+    }
+
+    void setFileName(const QString &fileName)
+    {
+        mFileName = fileName;
+    }
+
+    void setType(QtMsgType type)
+    {
+        mType = type;
+    }
+
+private:
+    QString mFileName;
+    QtMsgType mType;
+};
+
+class DebugPrivate
+{
+public:
+    DebugPrivate()
+        : origHandler(nullptr)
+    {
+    }
+
+    ~DebugPrivate()
+    {
+        qInstallMessageHandler(origHandler);
+        file.close();
+    }
+
+    void log(QtMsgType type, const QMessageLogContext &context, const QString &message)
+    {
+        QMutexLocker locker(&mutex);
+        QByteArray buf;
+        QTextStream str(&buf);
+        str << QDateTime::currentDateTime().toString(Qt::ISODate) << " [";
+        switch (type) {
+        case QtDebugMsg:
+            str << "DEBUG";
+            break;
+        case QtInfoMsg:
+            str << "INFO ";
+            break;
+        case QtWarningMsg:
+            str << "WARN ";
+            break;
+        case QtFatalMsg:
+            str << "FATAL";
+            break;
+        case QtCriticalMsg:
+            str << "CRITICAL";
+            break;
+        }
+        str << "] " << context.category << ": ";
+        if (context.file && *context.file && context.line) {
+            str << context.file << ":" << context.line << ": ";
+        }
+        if (context.function && *context.function) {
+            str << context.function << ": ";
+        }
+        str << message << "\n";
+        str.flush();
+        file.write(buf.constData(), buf.size());
+        file.flush();
+
+        if (oldHandler && (strcmp(context.category, "quotient.e2ee") != 0 || e2eeDebugEnabled)) {
+            oldHandler(type, context, message);
+        }
+    }
+
+    void setName(const QString &appName)
+    {
+        name = appName;
+
+        if (file.isOpen()) {
+            file.close();
+        }
+        auto filePath = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation) + QDir::separator() + appName;
+
+        QFileInfo infoOld(filePath + QLatin1String(".old"));
+        if (infoOld.exists()) {
+            QFile fileOld(infoOld.absoluteFilePath());
+            const bool success = fileOld.remove();
+            if (!success) {
+                qFatal("Cannot remove old log file '%s': %s", qUtf8Printable(fileOld.fileName()), qUtf8Printable(fileOld.errorString()));
+            }
+        }
+
+        QFileInfo info(filePath);
+        if (info.exists()) {
+            QFile file(info.absoluteFilePath());
+            const QString oldName = filePath + QLatin1String(".old");
+            const bool success = file.copy(oldName);
+            if (!success) {
+                qFatal("Cannot rename log file '%s' to '%s': %s", qUtf8Printable(file.fileName()), qUtf8Printable(oldName), qUtf8Printable(file.errorString()));
+            }
+        }
+
+        QFileInfo finfo(filePath);
+        if (!finfo.absoluteDir().exists()) {
+            QDir().mkpath(finfo.absolutePath());
+        }
+        file.setFileName(filePath);
+        file.open(QIODevice::WriteOnly | QIODevice::Unbuffered);
+    }
+
+    void setOrigHandler(QtMessageHandler origHandler_)
+    {
+        origHandler = origHandler_;
+    }
+
+    QMutex mutex;
+    QFile file;
+    QString name;
+    QtMessageHandler origHandler;
+    QByteArray loggingCategory;
+};
+
+Q_GLOBAL_STATIC(DebugPrivate, sInstance)
+
+void messageHandler(QtMsgType type, const QMessageLogContext &context, const QString &message)
+{
+    switch (type) {
+    case QtDebugMsg:
+    case QtInfoMsg:
+    case QtWarningMsg:
+    case QtCriticalMsg:
+        sInstance()->log(type, context, message);
+        break;
+    case QtFatalMsg:
+        sInstance()->log(QtInfoMsg, context, message);
+        abort();
+    }
+}
+
+void filter(QLoggingCategory *category)
+{
+    if (qstrcmp(category->categoryName(), "quotient.e2ee") == 0) {
+        category->setEnabled(QtDebugMsg, true);
+    } else if (oldCategoryFilter) {
+        oldCategoryFilter(category);
+    }
+}
+
+void initLogging()
+{
+    e2eeDebugEnabled = QLoggingCategory("quotient.e2ee", QtDebugMsg).isEnabled(QtDebugMsg);
+    oldCategoryFilter = QLoggingCategory::installFilter(filter);
+    oldHandler = qInstallMessageHandler(messageHandler);
+    sInstance->setOrigHandler(oldHandler);
+    sInstance->setName("neochat.log");
+}
+
+#include "logger.moc"

src/logger.h

@@ -0,0 +1,9 @@
+// SPDX-FileCopyrightText: 2023 Tobias Fella <tobias.fella@kde.org>
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+/**
+ * Initlalize logging to file and enables some additional categories, which will only be logged to the file
+ */
+void initLogging();

src/main.cpp

@@ -45,6 +45,7 @@
 #include "controller.h"
 #include "filetypesingleton.h"
 #include "linkpreviewer.h"
+#include "logger.h"
 #include "login.h"
 #include "matriximageprovider.h"
 #include "models/collapsestateproxymodel.h"
@@ -180,6 +181,8 @@ int main(int argc, char *argv[])
     KAboutData::setApplicationData(about);
     QGuiApplication::setWindowIcon(QIcon::fromTheme(QStringLiteral("org.kde.neochat")));
 
+    initLogging();
+
 #ifdef NEOCHAT_FLATPAK
     // Copy over the included FontConfig configuration to the
     // app's config dir: