From 3920485900a86011eed2b04c8627e78705a47ee7 Mon Sep 17 00:00:00 2001
From: arkadiusz <arkadius.bulinski@gmail.com>
Date: Fri, 26 Jul 2024 10:22:16 +0200
Subject: [PATCH] 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 | 12 ++++++++++--
 src/handler.hpp |  3 +++
 src/main.cpp    |  6 +++++-
 3 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/src/handler.cpp b/src/handler.cpp
index 1ac22e70..ae7b3a0c 100644
--- a/src/handler.cpp
+++ b/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;
+    }
+}
diff --git a/src/handler.hpp b/src/handler.hpp
index df5870eb..8e463997 100644
--- a/src/handler.hpp
+++ b/src/handler.hpp
@@ -5,6 +5,7 @@
 #include <nlohmann/json.hpp>
 #include <nlohmann/json_fwd.hpp>
 #include <set>
+#include <atomic>
 
 // global variables
 inline OmniscopeDeviceManager deviceManager{};
@@ -12,8 +13,10 @@ 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
diff --git a/src/main.cpp b/src/main.cpp
index fa4d1539..2d150429 100644
--- a/src/main.cpp
+++ b/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);