write debug log to file

debug.cpp

@@ -4,36 +4,63 @@
 #include <QDateTime>
 #include <QStandardPaths>
 #include <QDir>
+#include <QMutex>
 
 #include "dialogs/debugdialog.h"
 
 QString debug_info;
+QMutex debug_mutex;
+QFile debug_file;
+QTextStream debug_stream;
+
+void open_debug_file() {
+	QDir debug_dir = QStandardPaths::writableLocation(QStandardPaths::CacheLocation);
+	debug_dir.mkpath(".");
+	if (debug_dir.exists()) {
+		debug_file.setFileName(debug_dir.path() + "/debug_log");
+		if (debug_file.open(QFile::WriteOnly)) {
+			debug_stream.setDevice(&debug_file);
+		} else {
+			qWarning() << "Couldn't open debug log file, debug log will not be saved";
+		}
+	}
+}
+
+void close_debug_file() {
+	if (debug_file.isOpen()) debug_file.close();
+}
 
 void debug_message_handler(QtMsgType type, const QMessageLogContext &context, const QString &msg) {
+	debug_mutex.lock();
 	QByteArray localMsg = msg.toLocal8Bit();
 	switch (type) {
 	case QtDebugMsg:
 		fprintf(stderr, "[DEBUG] %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
+		if (debug_file.isOpen()) debug_stream << QString("[DEBUG] %1 (%2:%3, %4)\n").arg(localMsg.constData(), context.file, QString::number(context.line), context.function);
 		debug_info.prepend(QString("<b>[DEBUG]</b> %1 (%2:%3, %4)<br>").arg(localMsg.constData(), context.file, QString::number(context.line), context.function));
 		fflush(stderr);
 		break;
 	case QtInfoMsg:
 		fprintf(stderr, "[INFO] %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
+		if (debug_file.isOpen()) debug_stream << QString("[INFO] %1 (%2:%3, %4)\n").arg(localMsg.constData(), context.file, QString::number(context.line), context.function);
 		debug_info.prepend(QString("<b>[INFO]</b> %1 (%2:%3, %4)<br>").arg(localMsg.constData(), context.file, QString::number(context.line), context.function));
 		fflush(stderr);
 		break;
 	case QtWarningMsg:
 		fprintf(stderr, "[WARNING] %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
+		if (debug_file.isOpen()) debug_stream << QString("[WARNING] %1 (%2:%3, %4)\n").arg(localMsg.constData(), context.file, QString::number(context.line), context.function);
 		debug_info.prepend(QString("<font color='yellow'><b>[WARNING]</b> %1 (%2:%3, %4)</font><br>").arg(localMsg.constData(), context.file, QString::number(context.line), context.function));
 		fflush(stderr);
 		break;
 	case QtCriticalMsg:
 		fprintf(stderr, "[ERROR] %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
+		if (debug_file.isOpen()) debug_stream << QString("[ERROR] %1 (%2:%3, %4)\n").arg(localMsg.constData(), context.file, QString::number(context.line), context.function);
 		debug_info.prepend(QString("<font color='red'><b>[ERROR]</b> %1 (%2:%3, %4)</font><br>").arg(localMsg.constData(), context.file, QString::number(context.line), context.function));
 		fflush(stderr);
 		break;
 	case QtFatalMsg:
 		fprintf(stderr, "[FATAL] %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
+		if (debug_file.isOpen()) debug_stream << QString("[FATAL] %1 (%2:%3, %4)\n").arg(localMsg.constData(), context.file, QString::number(context.line), context.function);
 		debug_info.prepend(QString("<font color='red'><b>[FATAL]</b> %1 (%2:%3, %4)</font><br>").arg(localMsg.constData(), context.file, QString::number(context.line), context.function));
 		fflush(stderr);
 		abort();
@@ -41,6 +68,7 @@ void debug_message_handler(QtMsgType type, const QMessageLogContext &context, co
 	if (debug_dialog->isVisible()) {
 		QMetaObject::invokeMethod(debug_dialog, "update_log", Qt::QueuedConnection);
 	}
+	debug_mutex.unlock();
 }
 
 const QString &get_debug_str() {

debug.h

@@ -5,6 +5,8 @@
 
 void debug_message_handler(QtMsgType type, const QMessageLogContext &context, const QString &msg);
 const QString& get_debug_str();
+void open_debug_file();
+void close_debug_file();
 
 #define dout qDebug()
 

mainwindow.cpp

@@ -94,9 +94,11 @@ void MainWindow::setup_layout(bool reset) {
 
 MainWindow::MainWindow(QWidget *parent, const QString &an) :
 	QMainWindow(parent),
-	appName(an),
-	enable_launch_with_project(false)
+	enable_launch_with_project(false),
+	appName(an)
 {
+	open_debug_file();
+
 	debug_dialog = new DebugDialog(this);
 
 	mainWindow = this;
@@ -227,6 +229,7 @@ MainWindow::MainWindow(QWidget *parent, const QString &an) :
 
 MainWindow::~MainWindow() {
 	free_panels();
+	close_debug_file();
 }
 
 void MainWindow::launch_with_project(const QString& s) {