feat(ipc): Core IPC server and connected client

src/apps/deskflow-core/deskflow-core.cpp

@@ -15,6 +15,7 @@
 #include "common/ExitCodes.h"
 #include "deskflow/ClientApp.h"
 #include "deskflow/ServerApp.h"
+#include "deskflow/ipc/CoreIpcServer.h"
 
 #if defined(Q_OS_WIN)
 #include "arch/win32/ArchMiscWindows.h"
@@ -104,6 +105,9 @@ int main(int argc, char **argv)
   QCoreApplication app(argc, argv);
   QCoreApplication::setApplicationName(QStringLiteral("%1 Core").arg(kAppName));
 
+  const auto ipcServer = new deskflow::core::ipc::CoreIpcServer(&app); // NOSONAR - Qt managed
+  ipcServer->listen();
+
   QThread coreThread;
   QObject::connect(&coreThread, &QThread::finished, &app, &QCoreApplication::quit);
   coreApp->run(coreThread);

src/lib/common/Constants.h.in

@@ -21,6 +21,7 @@ const auto kCopyright = //
     "Copyright (C) 2002-2009 Chris Schoeneman";
 
 const auto kCoreBinName = "@CORE_BINARY@";
+const auto kCoreIpcName = "@CMAKE_PROJECT_NAME@-core";
 
 #ifdef _WIN32
 

src/lib/deskflow/CMakeLists.txt

@@ -83,6 +83,8 @@ add_library(${lib_name} STATIC ${PLATFORM_CODE}
   ipc/IpcServer.h
   ipc/DaemonIpcServer.cpp
   ipc/DaemonIpcServer.h
+  ipc/CoreIpcServer.cpp
+  ipc/CoreIpcServer.h
 )
 
 target_link_libraries(${lib_name} PUBLIC common Qt6::Core Qt6::Network)

src/lib/deskflow/ipc/CoreIpcServer.cpp

@@ -0,0 +1,28 @@
+/*
+ * Deskflow -- mouse and keyboard sharing utility
+ * SPDX-FileCopyrightText: (C) 2025-2026 Symless Ltd.
+ * SPDX-License-Identifier: GPL-2.0-only WITH LicenseRef-OpenSSL-Exception
+ */
+
+#include "CoreIpcServer.h"
+
+#include "base/Log.h"
+#include "common/Constants.h"
+
+#include <QLocalSocket>
+
+namespace deskflow::core::ipc {
+
+CoreIpcServer::CoreIpcServer(QObject *parent) : IpcServer(parent, kCoreIpcName)
+{
+  // do nothing
+}
+
+void CoreIpcServer::processCommand(QLocalSocket *clientSocket, const QString &command, const QStringList &parts)
+{
+  Q_UNUSED(clientSocket)
+  Q_UNUSED(parts)
+  LOG_WARN("core ipc server got unknown command: %s", command.toUtf8().constData());
+}
+
+} // namespace deskflow::core::ipc

src/lib/deskflow/ipc/CoreIpcServer.h

@@ -0,0 +1,29 @@
+/*
+ * Deskflow -- mouse and keyboard sharing utility
+ * SPDX-FileCopyrightText: (C) 2025-2026 Symless Ltd.
+ * SPDX-License-Identifier: GPL-2.0-only WITH LicenseRef-OpenSSL-Exception
+ */
+
+#pragma once
+
+#include "IpcServer.h"
+
+#include <QObject>
+#include <QSet>
+
+class QLocalSocket;
+
+namespace deskflow::core::ipc {
+
+class CoreIpcServer : public IpcServer
+{
+  Q_OBJECT
+
+public:
+  explicit CoreIpcServer(QObject *parent);
+
+private:
+  void processCommand(QLocalSocket *clientSocket, const QString &command, const QStringList &parts) override;
+};
+
+} // namespace deskflow::core::ipc

src/lib/deskflow/ipc/DaemonIpcServer.cpp

@@ -23,29 +23,14 @@ DaemonIpcServer::DaemonIpcServer(QObject *parent, const QString &logFilename)
   // do nothing
 }
 
-void DaemonIpcServer::processMessage(QLocalSocket *clientSocket, const QString &message)
+void DaemonIpcServer::processCommand(QLocalSocket *clientSocket, const QString &command, const QStringList &parts)
 {
-  LOG_DEBUG1("daemon ipc server got message: %s", message.toUtf8().constData());
+  if (command == "logLevel") {
-  const auto parts = message.split('=');
-  if (parts.size() < 1) {
-    LOG_ERR("daemon ipc server got invalid message: %s", message.toUtf8().constData());
-    writeToClientSocket(clientSocket, kErrorMessage);
-    return;
-  }
-
-  const auto &command = parts[0];
-  if (command == "hello") { // NOSONAR - if-init is confusing here
-    LOG_DEBUG("daemon ipc server got hello message, sending hello back");
-    writeToClientSocket(clientSocket, "hello");
-  } else if (command == "noop") {
-    LOG_DEBUG("daemon ipc server got noop message");
-    writeToClientSocket(clientSocket, kAckMessage);
-  } else if (command == "logLevel") {
     processLogLevel(clientSocket, parts);
   } else if (command == "elevate") {
     processElevate(clientSocket, parts);
   } else if (command == "command") {
-    processCommand(clientSocket, parts);
+    processCommandMessage(clientSocket, parts);
   } else if (command == "start") {
     LOG_DEBUG("daemon ipc server got start message");
     Q_EMIT startProcessRequested();
@@ -62,10 +47,8 @@ void DaemonIpcServer::processMessage(QLocalSocket *clientSocket, const QString &
     Q_EMIT clearSettingsRequested();
     writeToClientSocket(clientSocket, kAckMessage);
   } else {
-    LOG_WARN("daemon ipc server got unknown message: %s", message.toUtf8().constData());
+    LOG_WARN("daemon ipc server got unknown command: %s", command.toUtf8().constData());
   }
-
-  clientSocket->flush();
 }
 
 void DaemonIpcServer::processLogLevel(QLocalSocket *&clientSocket, const QStringList &messageParts)
@@ -108,7 +91,7 @@ void DaemonIpcServer::processElevate(QLocalSocket *&clientSocket, const QStringL
   writeToClientSocket(clientSocket, kAckMessage);
 }
 
-void DaemonIpcServer::processCommand(QLocalSocket *&clientSocket, const QStringList &messageParts)
+void DaemonIpcServer::processCommandMessage(QLocalSocket *&clientSocket, const QStringList &messageParts)
 {
   if (messageParts.size() < 2) {
     LOG_ERR("daemon ipc server got invalid command message");

src/lib/deskflow/ipc/DaemonIpcServer.h

@@ -23,10 +23,10 @@ public:
   explicit DaemonIpcServer(QObject *parent, const QString &logFilename);
 
 private:
-  void processMessage(QLocalSocket *clientSocket, const QString &message) override;
+  void processCommand(QLocalSocket *clientSocket, const QString &command, const QStringList &parts) override;
   void processLogLevel(QLocalSocket *&clientSocket, const QStringList &messageParts);
   void processElevate(QLocalSocket *&clientSocket, const QStringList &messageParts);
-  void processCommand(QLocalSocket *&clientSocket, const QStringList &messageParts);
+  void processCommandMessage(QLocalSocket *&clientSocket, const QStringList &messageParts);
 
 private:
   const QString m_logFilename;

src/lib/deskflow/ipc/IpcServer.cpp

@@ -13,9 +13,6 @@
 
 namespace deskflow::core::ipc {
 
-const auto kAckMessage = "ok";
-const auto kErrorMessage = "error";
-
 IpcServer::IpcServer(QObject *parent, const QString &serverName)
     : QObject(parent),
       m_server{new QLocalServer(this)}, // NOSONAR - Qt memory
@@ -102,6 +99,29 @@ void IpcServer::handleErrorOccurred()
   clientSocket->deleteLater();
 }
 
+void IpcServer::processMessage(QLocalSocket *clientSocket, const QString &message)
+{
+  LOG_DEBUG1("ipc server got message: %s", message.toUtf8().constData());
+  const auto parts = message.split('=');
+  if (parts.isEmpty()) {
+    LOG_ERR("ipc server got invalid message: %s", message.toUtf8().constData());
+    writeToClientSocket(clientSocket, "error");
+    return;
+  }
+
+  if (const auto &command = parts.at(0); command == "hello") {
+    LOG_DEBUG("ipc server got hello message, sending hello back");
+    writeToClientSocket(clientSocket, "hello");
+  } else if (command == "noop") {
+    LOG_DEBUG("ipc server got noop message");
+    writeToClientSocket(clientSocket, "ok");
+  } else {
+    processCommand(clientSocket, command, parts);
+  }
+
+  clientSocket->flush();
+}
+
 void IpcServer::writeToClientSocket(QLocalSocket *&clientSocket, const QString &message) const
 {
   QByteArray messageData = message.toUtf8() + '\n';

src/lib/deskflow/ipc/IpcServer.h

@@ -42,7 +42,8 @@ protected:
   void writeToClientSocket(QLocalSocket *&clientSocket, const QString &message) const;
 
 private:
-  virtual void processMessage(QLocalSocket *clientSocket, const QString &message) = 0;
+  void processMessage(QLocalSocket *clientSocket, const QString &message);
+  virtual void processCommand(QLocalSocket *clientSocket, const QString &command, const QStringList &parts) = 0;
   void handleNewConnection();
   void handleReadyRead();
   void handleDisconnected();

src/lib/gui/CMakeLists.txt

@@ -85,6 +85,8 @@ add_library(${target} STATIC
   ipc/IpcClient.h
   ipc/DaemonIpcClient.cpp
   ipc/DaemonIpcClient.h
+  ipc/CoreIpcClient.cpp
+  ipc/CoreIpcClient.h
   validators/AliasValidator.cpp
   validators/AliasValidator.h
   validators/ComputerNameValidator.cpp

src/lib/gui/core/CoreProcess.cpp

@@ -8,6 +8,7 @@
 #include "CoreProcess.h"
 
 #include "common/ExitCodes.h"
+#include "gui/ipc/CoreIpcClient.h"
 #include "gui/ipc/DaemonIpcClient.h"
 
 #if defined(Q_OS_MACOS)
@@ -372,6 +373,21 @@ void CoreProcess::start(std::optional<ProcessMode> processModeOption)
     startProcessFromDaemon(args);
   }
 
+  // Don't block the main GUI render thread when connecting to the Core IPC server.
+  QTimer::singleShot(kRetryDelay, this, [this] {
+    if (m_processState != ProcessState::Started) {
+      qWarning("core process failed to start, skipping core ipc connection");
+      return;
+    }
+
+    m_coreIpcClient = new ipc::CoreIpcClient(this);
+    if (m_coreIpcClient->connectToServer()) {
+      qInfo("connected to core ipc server");
+    } else {
+      qWarning("failed to establish core ipc connection");
+    }
+  });
+
   m_lastProcessMode = processMode;
 }
 
@@ -384,6 +400,12 @@ void CoreProcess::stop(std::optional<ProcessMode> processModeOption)
 
   qInfo("stopping core process (%s mode)", qPrintable(processModeToString(processMode)));
 
+  if (m_coreIpcClient) {
+    m_coreIpcClient->disconnectFromServer();
+    delete m_coreIpcClient;
+    m_coreIpcClient = nullptr;
+  }
+
   if (m_processState == ProcessState::Starting) {
     qDebug("core process is starting, cancelling");
     setProcessState(ProcessState::Stopped);

src/lib/gui/core/CoreProcess.h

@@ -20,6 +20,7 @@
 namespace deskflow::gui {
 
 namespace ipc {
+class CoreIpcClient;
 class DaemonIpcClient;
 }
 
@@ -128,6 +129,7 @@ private:
   std::optional<ProcessMode> m_lastProcessMode = std::nullopt;
   QTimer m_retryTimer;
   int m_connections = 0;
+  deskflow::gui::ipc::CoreIpcClient *m_coreIpcClient = nullptr;
   deskflow::gui::ipc::DaemonIpcClient *m_daemonIpcClient = nullptr;
   FileTail *m_daemonFileTail = nullptr;
   QProcess *m_process = nullptr;

src/lib/gui/ipc/CoreIpcClient.cpp

@@ -0,0 +1,25 @@
+/*
+ * Deskflow -- mouse and keyboard sharing utility
+ * SPDX-FileCopyrightText: (C) 2025-2026 Symless Ltd.
+ * SPDX-License-Identifier: GPL-2.0-only WITH LicenseRef-OpenSSL-Exception
+ */
+
+#include "CoreIpcClient.h"
+
+#include "common/Constants.h"
+
+#include <QDebug>
+#include <QLocalSocket>
+#include <QObject>
+#include <QString>
+
+namespace deskflow::gui::ipc {
+
+const auto kTimeout = 1000;
+
+CoreIpcClient::CoreIpcClient(QObject *parent) : IpcClient(parent, kCoreIpcName)
+{
+  // do nothing
+}
+
+} // namespace deskflow::gui::ipc

src/lib/gui/ipc/CoreIpcClient.h

@@ -0,0 +1,23 @@
+/*
+ * Deskflow -- mouse and keyboard sharing utility
+ * SPDX-FileCopyrightText: (C) 2025-2026 Symless Ltd.
+ * SPDX-License-Identifier: GPL-2.0-only WITH LicenseRef-OpenSSL-Exception
+ */
+
+#pragma once
+
+#include "IpcClient.h"
+
+#include <QObject>
+
+namespace deskflow::gui::ipc {
+
+class CoreIpcClient : public IpcClient
+{
+  Q_OBJECT
+
+public:
+  explicit CoreIpcClient(QObject *parent = nullptr);
+};
+
+} // namespace deskflow::gui::ipc