From 0fa0cbbc099ff6ac126ba2dc7e756d4d3cb97094 Mon Sep 17 00:00:00 2001
From: lisyarus <lisyarus@gmail.com>
Date: Fri, 25 Feb 2022 14:52:48 +0300
Subject: [PATCH] Support audio::stream on_stop callback

---
 libs/audio/include/psemek/audio/stream.hpp |  4 ++++
 libs/audio/source/engine.cpp               | 23 +++++++++++++++++++---
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/libs/audio/include/psemek/audio/stream.hpp b/libs/audio/include/psemek/audio/stream.hpp
index e78ae218..e76b2d8c 100644
--- a/libs/audio/include/psemek/audio/stream.hpp
+++ b/libs/audio/include/psemek/audio/stream.hpp
@@ -2,6 +2,8 @@
 
 #include <psemek/audio/effect.hpp>
 
+#include <psemek/util/function.hpp>
+
 #include <memory>
 
 namespace psemek::audio
@@ -22,6 +24,8 @@ namespace psemek::audio
 		virtual void stop() = 0;
 		virtual bool is_playing() const = 0;
 
+		virtual void on_stop(util::function<void()> callback) = 0;
+
 		virtual ~stream() {}
 	};
 
diff --git a/libs/audio/source/engine.cpp b/libs/audio/source/engine.cpp
index 1c23dcca..52e8bad6 100644
--- a/libs/audio/source/engine.cpp
+++ b/libs/audio/source/engine.cpp
@@ -85,6 +85,8 @@ namespace psemek::audio
 
 			std::vector<std::shared_ptr<effect>> effects;
 
+			util::function<void()> callback;
+
 			stream_impl(int channel, std::shared_ptr<track_impl> track, bool loop, spec_t spec)
 				: channel(channel)
 				, track(track)
@@ -152,6 +154,11 @@ namespace psemek::audio
 			{
 				return playing;
 			}
+
+			void on_stop(util::function<void()> callback) override
+			{
+				this->callback = std::move(callback);
+			}
 		};
 
 	}
@@ -268,9 +275,19 @@ namespace psemek::audio
 		}
 		if (!self) return;
 
-		std::lock_guard lock{self->channels_mutex};
-		self->channels[ch].stream->playing = false;
-		self->channels[ch].stream = nullptr;
+		util::function<void()> callback;
+		{
+			// callback will probably lock something as well,
+			// leading to a deadlock, so we have to call the
+			// callback outside of the lock
+			std::lock_guard lock{self->channels_mutex};
+			self->channels[ch].stream->playing = false;
+			callback = std::move(self->channels[ch].stream->callback);
+			self->channels[ch].stream = nullptr;
+		}
+
+		if (callback)
+			callback();
 	}
 
 	engine::engine()