Add signal handling for orderly shutdown

- Add 'signalHandler' function to handle SIGINT for graceful shutdown
- Update 'consoleHandler' and WebSocket handler loop to check for a 'running' atomic flag
- Signal processing in 'main.cpp' to intercept SIGINT and set the 'running' flag to false
- Add '<csignal>' and '<atomic>' headers for signal handling and atomic operations

These changes ensure that the application can be terminated properly when interrupted by SIGINT (Ctrl+C).

src/handler.cpp

@@ -1,6 +1,7 @@
 #include "handler.hpp"
 #include <iostream>
 #include <thread>
+#include <csignal>
 
 // A list of colors
 const std::array<std::array<float, 3>, 7> predefinedColors = {{
@@ -35,7 +36,7 @@ void initDevices() {
 
 void consoleHandler(bool &flagPaused, std::set<std::string>& selected_serials) {
     std::string input;
-    while (true) {
+    while (running) {
         std::cout << "Enter command: ";
         std::getline(std::cin, input);
         if (input == "Search") {
@@ -90,4 +91,11 @@ void consoleHandler(bool &flagPaused, std::set<std::string>& selected_serials) {
             }
         }
     }
-} 
+}
+
+void signalHandler(int signal) {
+    if (signal == SIGINT) {
+        std::cout << "\nSIGINT received, shutting down gracefully...\n";
+        running = false;
+    }
+}

src/handler.hpp

@@ -5,15 +5,18 @@
 #include <nlohmann/json.hpp>
 #include <nlohmann/json_fwd.hpp>
 #include <set>
+#include <atomic>
 
 // global variables
 inline OmniscopeDeviceManager deviceManager{};
 inline std::vector<std::shared_ptr<OmniscopeDevice>> devices;
 inline std::map<Omniscope::Id, std::array<float, 3>> colorMap;
 inline std::optional<OmniscopeSampler> sampler{};
 inline std::map<Omniscope::Id, std::vector<std::pair<double, double>>> captureData;
+inline std::atomic<bool> running{true};
 
 void initDevices();
 void consoleHandler(bool &flagPaused, std::set<std::string>& selected_serials);
+void signalHandler(int signal);
 
 #endif

src/main.cpp

@@ -2,6 +2,7 @@
 #include "handler.hpp"
 #include <thread>
 #include <CLI/CLI.hpp>
+#include <csignal>
 
 int main(int argc, char** argv) {
 
@@ -17,12 +18,15 @@ int main(int argc, char** argv) {
 
     WebSocketHandler wsHandler(wsURI);
 
+    // Signal handler for SIGINT
+    std::signal(SIGINT, signalHandler);
+
     // Start console handler thread
     std::thread consoleThread(consoleHandler, std::ref(flagPaused), std::ref(selected_serials));
 
     // WebSocket handler thread
     std::thread webSocketThread([&]() {
-        while (true) {
+        while (running) {
             if (sampler.has_value() && !flagPaused) {
             sampler->copyOut(captureData);
             wsHandler.send(captureData, selected_serials);