Added subscription service capability.

Subscription.cpp

@@ -0,0 +1,38 @@
+#include "Subscription.h"
+
+namespace core {
+
+   Subscription::Subscription(std::string id, TCPSession &session) : id(id), owner(&session) {}
+
+   int Subscription::subscribe(TCPSession &session) {
+      subscribers.push_back(&session);
+      return 1;
+   }
+
+   int Subscription::unsubscribe(TCPSession &session) {
+      for(auto subscriber = subscribers.begin(); subscriber < subscribers.end(); ++subscriber) {
+         if(*subscriber == &session) {
+            subscribers.erase(subscriber);
+            return 1;
+         }
+      }
+      return 0;
+   }
+
+   int Subscription::process(coreutils::ZString &request, std::stringstream &out) {
+      out << "event:" << request[1] << ":" << request[2] << std::endl;
+      return 1;
+   }
+
+   int Subscription::event(std::stringstream &out) {
+      for(auto subscriber = subscribers.begin(); subscriber < subscribers.end(); ++subscriber)
+        (*subscriber)->write(out.str());
+      return 1;
+   }
+
+   int Subscription::processCommand(coreutils::ZString &request, TCPSession &session) {
+      session.out << "Generic subscription passthrough";
+      return 1;
+   }
+
+}