From 7349f8ef0fdc384973d1ed9ec256d36a0be9e1ec Mon Sep 17 00:00:00 2001
From: JadingTsunami <JadingTsunami@users.noreply.github.com>
Date: Wed, 21 Apr 2021 00:12:57 -0700
Subject: [PATCH] Fix for UMAPINFO music restarting issue. (#281)

* Fix for UMAPINFO music restarting issue.

* Fix bugs with MUSINFO and UMAPINFO present simultaneously.

Fixes #279, fixes #102.
---
 prboom2/src/s_advsound.c | 20 ++++++++++++++++----
 prboom2/src/s_advsound.h |  2 ++
 prboom2/src/s_sound.c    |  4 +++-
 3 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/prboom2/src/s_advsound.c b/prboom2/src/s_advsound.c
index 1490006cf..415c4d509 100644
--- a/prboom2/src/s_advsound.c
+++ b/prboom2/src/s_advsound.c
@@ -59,15 +59,27 @@ musinfo_t musinfo;
 //
 void S_ParseMusInfo(const char *mapid)
 {
-  memset(&musinfo, 0, sizeof(musinfo));
-  musinfo.current_item = -1;
-
-  S_music[NUMMUSIC].lumpnum = -1;
 
   if (W_CheckNumForName("MUSINFO") != -1)
   {
     int num, lumpnum;
     int inMap = false;
+    int load_muslump = -1;
+    /* musinfo item zero is initialized
+     * before we reach the parser and it must be
+     * saved and restored */
+    int itemzero = musinfo.items[0];
+
+    /* don't restart music that is already playing */
+    if (mus_playing &&
+        mus_playing->lumpnum == S_music[NUMMUSIC].lumpnum) {
+        load_muslump = S_music[NUMMUSIC].lumpnum;
+    }
+
+    memset(&musinfo, 0, sizeof(musinfo));
+    musinfo.items[0] = itemzero;
+    musinfo.current_item = load_muslump;
+    S_music[NUMMUSIC].lumpnum = load_muslump;
 
     SC_OpenLump("MUSINFO");
 
diff --git a/prboom2/src/s_advsound.h b/prboom2/src/s_advsound.h
index 1bdeb8894..0db760eea 100644
--- a/prboom2/src/s_advsound.h
+++ b/prboom2/src/s_advsound.h
@@ -35,6 +35,7 @@
 #define __S_ADVSOUND__
 
 #include "p_mobj.h"
+#include "sounds.h"
 
 #ifdef __GNUG__
 #pragma interface
@@ -55,6 +56,7 @@ typedef struct musinfo_s
   int items[MAX_MUS_ENTRIES];
 } musinfo_t;
 
+extern musicinfo_t *mus_playing;
 extern musinfo_t musinfo;
 
 void S_ParseMusInfo(const char *mapid);
diff --git a/prboom2/src/s_sound.c b/prboom2/src/s_sound.c
index 63d5cc2b8..5e19a20d1 100644
--- a/prboom2/src/s_sound.c
+++ b/prboom2/src/s_sound.c
@@ -95,7 +95,7 @@ int snd_MusicVolume = 15;
 static dboolean mus_paused;
 
 // music currently being played
-static musicinfo_t *mus_playing;
+musicinfo_t *mus_playing;
 
 // music currently should play
 static int musicnum_current;
@@ -207,6 +207,7 @@ void S_Start(void)
 	  int muslump = W_CheckNumForName(gamemapinfo->music);
 	  if (muslump >= 0)
 	  {
+		  musinfo.items[0] = muslump;
 		  S_ChangeMusInfoMusic(muslump, true);
 		  return;
 	  }
@@ -533,6 +534,7 @@ void S_ChangeMusic(int musicnum, int looping)
   // current music which should play
   musicnum_current = musicnum;
   musinfo.current_item = -1;
+  S_music[NUMMUSIC].lumpnum = -1;
 
   //jff 1/22/98 return if music is not enabled
   if (!mus_card || nomusicparm)