From 38b9822860cfeb7c666c3ba88255e6da6febc4e3 Mon Sep 17 00:00:00 2001
From: nsubiron <nsubiron@cvc.uab.es>
Date: Tue, 16 Oct 2018 12:48:36 +0200
Subject: [PATCH] Make sure we don't subscribe twice to same stream

---
 LibCarla/source/carla/streaming/Client.h           | 2 ++
 LibCarla/source/carla/streaming/low_level/Client.h | 3 +++
 2 files changed, 5 insertions(+)

diff --git a/LibCarla/source/carla/streaming/Client.h b/LibCarla/source/carla/streaming/Client.h
index 9b6d8324d..d29ffba3d 100644
--- a/LibCarla/source/carla/streaming/Client.h
+++ b/LibCarla/source/carla/streaming/Client.h
@@ -33,6 +33,8 @@ namespace streaming {
       _service.Stop();
     }
 
+    /// @warning cannot subscribe twice to the same stream (even if it's a
+    /// MultiStream).
     template <typename Functor>
     void Subscribe(const Token &token, Functor &&callback) {
       _client.Subscribe(_service.service(), token, std::forward<Functor>(callback));
diff --git a/LibCarla/source/carla/streaming/low_level/Client.h b/LibCarla/source/carla/streaming/low_level/Client.h
index 71a7ad94b..533a7e3e1 100644
--- a/LibCarla/source/carla/streaming/low_level/Client.h
+++ b/LibCarla/source/carla/streaming/low_level/Client.h
@@ -46,11 +46,14 @@ namespace low_level {
       }
     }
 
+    /// @warning cannot subscribe twice to the same stream (even if it's a
+    /// MultiStream).
     template <typename Functor>
     void Subscribe(
         boost::asio::io_service &io_service,
         token_type token,
         Functor &&callback) {
+      DEBUG_ASSERT_EQ(_clients.find(token.get_stream_id()), _clients.end());
       if (!token.has_address()) {
         token.set_address(_fallback_address);
       }