Add AMX to message struct for reliable callback invoking

Previous implementation processed the entire message queue on the first
loaded AMX which could be an unrelated script. Now it takes the AMX
pointer and stores it on the message struct and uses that to invoke the
callback.

src/impl.cpp

@@ -395,7 +395,7 @@ int Impl::HIncrByFloat(int client_id, std::string key, std::string field, float
     return 0;
 }
 
-int Impl::Subscribe(std::string host, int port, std::string auth, std::string channel, std::string callback, int& id)
+int Impl::Subscribe(AMX* amx, std::string host, int port, std::string auth, std::string channel, std::string callback, int& id)
 {
     cpp_redis::subscriber* sub = new cpp_redis::subscriber();
     sub->connect(host, port);
@@ -404,8 +404,9 @@ int Impl::Subscribe(std::string host, int port, std::string auth, std::string ch
         sub->auth(auth);
     }
 
-    sub->subscribe(channel, [callback](const std::string& chan, const std::string& msg) {
+    sub->subscribe(channel, [amx, callback](const std::string& chan, const std::string& msg) {
         message m;
+        m.amx = amx;
         m.channel = chan;
         m.msg = msg;
         m.callback = callback;
@@ -467,7 +468,7 @@ int Impl::Publish(int client_id, std::string channel, std::string data)
     return 0;
 }
 
-void Impl::amx_tick(AMX* amx)
+void Impl::amx_tick()
 {
     if (message_stack_mutex.try_lock()) {
         message m;
@@ -480,6 +481,8 @@ void Impl::amx_tick(AMX* amx)
         while (!message_stack.empty()) {
             m = message_stack.top();
 
+            AMX* amx = m.amx;
+
             error = amx_FindPublic(amx, m.callback.c_str(), &amx_idx);
 
             if (error == AMX_ERR_NONE) {

src/impl.hpp

@@ -66,6 +66,7 @@ struct message {
     std::string channel;
     std::string msg;
     std::string callback;
+	AMX* amx;
 };
 
 int Connect(std::string hostname, int port, std::string auth, int& id);
@@ -87,13 +88,13 @@ int HIncrBy(int client_id, std::string key, std::string field, int incr);
 int HIncrByFloat(int client_id, std::string key, std::string field, float incr);
 int HDel(int client_id, std::string key, std::string field);
 
-int Subscribe(std::string host, int port, std::string auth, std::string channel, std::string callback, int& id);
+int Subscribe(AMX* amx, std::string host, int port, std::string auth, std::string channel, std::string callback, int& id);
 int Unsubscribe(int client_id);
 int Publish(int client_id, std::string channel, std::string message);
 
 int clientFromID(int client_id, cpp_redis::client*& client);
 int clientDataFromID(int client_id, clientData& client);
-void amx_tick(AMX* amx);
+void amx_tick();
 std::vector<std::string> split(const std::string s);
 
 extern int context_count;

src/main.cpp

@@ -95,9 +95,7 @@ PLUGIN_EXPORT void PLUGIN_CALL Unload()
 
 PLUGIN_EXPORT void PLUGIN_CALL ProcessTick()
 {
-    for (AMX* i : amx_list) {
-        Impl::amx_tick(i);
-    }
+    Impl::amx_tick();
 }
 
 PLUGIN_EXPORT int PLUGIN_CALL AmxLoad(AMX* amx)

src/natives.cpp

@@ -357,7 +357,7 @@ cell Natives::Subscribe(AMX* amx, cell* params)
 	cell* addr;
 	amx_GetAddr(amx, params[6], &addr);
     try {
-        return Impl::Subscribe(host, port, auth, channel, callback, *addr);
+        return Impl::Subscribe(amx, host, port, auth, channel, callback, *addr);
     }
     catch (cpp_redis::redis_error e) {
         logprintf("ERROR: %s", e.what());