Websocket re-architecture with websocketd and websocat (#89)

- Replaced beast with websocketd and websocat. #79 #83 #84
- Implemented inbound/outbound peer connection merging.
- Added graceful shutdown of hpcore with sigint. #87

src/util.cpp

@@ -188,7 +188,7 @@ std::string_view getsv(const rapidjson::Value &v)
     return std::string_view(v.GetString(), v.GetStringLength());
 }
 
-// provide a safe std::string overload for realpath
+// Provide a safe std::string overload for realpath
 std::string realpath(std::string path)
 {
     std::array<char, PATH_MAX> buffer;
@@ -197,4 +197,13 @@ std::string realpath(std::string path)
     return buffer.data();
 }
 
+// Applies signal mask to the calling thread.
+void mask_signal()
+{
+    sigset_t mask;
+    sigemptyset(&mask);
+    sigaddset(&mask, SIGINT);
+    pthread_sigmask(SIG_BLOCK, &mask, NULL);
+}
+
 } // namespace util