From d063aa077a481000192fbff9c5d1fa7c47962ba7 Mon Sep 17 00:00:00 2001
From: Alexander van Gessel <ai0867@gmail.com>
Date: Fri, 20 Oct 2017 17:31:09 +0200
Subject: [PATCH] Don't use invalid music indices. Fixes #1861

---
 src/scripting/lua_audio.cpp | 4 ++--
 src/sound.cpp               | 6 +++++-
 src/sound.hpp               | 3 ++-
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/scripting/lua_audio.cpp b/src/scripting/lua_audio.cpp
index 23122c9c8c5f..8df985b3bf39 100644
--- a/src/scripting/lua_audio.cpp
+++ b/src/scripting/lua_audio.cpp
@@ -96,8 +96,8 @@ static int impl_music_get(lua_State* L) {
 	}
 
 	if(strcmp(m, "current_i") == 0) {
-		size_t i = sound::get_current_track();
-		if(i == sound::get_num_tracks()) {
+		size_t i = sound::get_current_track_index();
+		if(i >= sound::get_num_tracks()) {
 			lua_pushnil(L);
 		} else {
 			lua_pushinteger(L, i + 1);
diff --git a/src/sound.cpp b/src/sound.cpp
index 71f0ae08d274..cf458967339e 100644
--- a/src/sound.cpp
+++ b/src/sound.cpp
@@ -190,10 +190,14 @@ std::vector<std::shared_ptr<sound::music_track>>::const_iterator find_track(cons
 
 namespace sound
 {
-unsigned int get_current_track()
+unsigned int get_current_track_index()
 {
 	return current_track_index;
 }
+std::shared_ptr<music_track> get_current_track()
+{
+	return current_track;
+}
 std::shared_ptr<music_track> get_previous_music_track()
 {
 	return previous_track;
diff --git a/src/sound.hpp b/src/sound.hpp
index 20eb6ff6dc68..c1707c5e9fff 100644
--- a/src/sound.hpp
+++ b/src/sound.hpp
@@ -104,7 +104,8 @@ void set_sound_volume(int vol);
 void set_bell_volume(int vol);
 void set_UI_volume(int vol);
 
-unsigned int get_current_track();
+unsigned int get_current_track_index(); // This function may return a value >= get_num_tracks(). Use with caution
+std::shared_ptr<sound::music_track> get_current_track();
 std::shared_ptr<sound::music_track> get_previous_music_track();
 void set_previous_track(std::shared_ptr<music_track>);
 unsigned int get_num_tracks();