From 8fe63689a420010c3498ff235edf3cfd99a78b0a Mon Sep 17 00:00:00 2001
From: Dean Herbert <pe@ppy.sh>
Date: Sat, 5 Nov 2016 18:16:15 +0900
Subject: [PATCH] Fix thread safety issue when accessing files in beatmap (zip)
 files.

---
 .../Tests/TestCasePlayer.cs                   |  9 +++-----
 osu.Game/Beatmaps/WorkingBeatmap.cs           | 23 +++++++++++++------
 osu.Game/Database/BeatmapDatabase.cs          |  4 +---
 3 files changed, 20 insertions(+), 16 deletions(-)

diff --git a/osu.Desktop.VisualTests/Tests/TestCasePlayer.cs b/osu.Desktop.VisualTests/Tests/TestCasePlayer.cs
index a3ae103f28..1d292442e6 100644
--- a/osu.Desktop.VisualTests/Tests/TestCasePlayer.cs
+++ b/osu.Desktop.VisualTests/Tests/TestCasePlayer.cs
@@ -46,13 +46,10 @@ namespace osu.Desktop.VisualTests.Tests
 
             Add(new Player
             {
-                Beatmap = new WorkingBeatmap
+                Beatmap = new WorkingBeatmap(new Beatmap
                 {
-                    Beatmap = new Beatmap
-                    {
-                        HitObjects = objects
-                    }
-                }
+                    HitObjects = objects
+                })
             });
         }
 
diff --git a/osu.Game/Beatmaps/WorkingBeatmap.cs b/osu.Game/Beatmaps/WorkingBeatmap.cs
index 4deed53465..a2a0a27e02 100644
--- a/osu.Game/Beatmaps/WorkingBeatmap.cs
+++ b/osu.Game/Beatmaps/WorkingBeatmap.cs
@@ -12,9 +12,12 @@ namespace osu.Game.Beatmaps
 {
     public class WorkingBeatmap : IDisposable
     {
-        public BeatmapInfo BeatmapInfo;
+        public readonly BeatmapInfo BeatmapInfo;
 
-        public readonly ArchiveReader Reader;
+        public readonly BeatmapSetInfo BeatmapSetInfo;
+        private readonly BeatmapDatabase database;
+
+        private ArchiveReader reader => database.GetReader(BeatmapSetInfo);
 
         private Beatmap beatmap;
         public Beatmap Beatmap
@@ -25,7 +28,7 @@ namespace osu.Game.Beatmaps
 
                 try
                 {
-                    using (var stream = new StreamReader(Reader.ReadFile(BeatmapInfo.Path)))
+                    using (var stream = new StreamReader(reader.ReadFile(BeatmapInfo.Path)))
                         beatmap = BeatmapDecoder.GetDecoder(stream)?.Decode(stream);
                 }
                 catch { }
@@ -44,7 +47,7 @@ namespace osu.Game.Beatmaps
 
                 try
                 {
-                    var trackData = Reader.ReadFile(BeatmapInfo.Metadata.AudioFile);
+                    var trackData = reader.ReadFile(BeatmapInfo.Metadata.AudioFile);
                     if (trackData != null)
                         track = new AudioTrackBass(trackData);
                 }
@@ -55,10 +58,16 @@ namespace osu.Game.Beatmaps
             set { track = value; }
         }
 
-        public WorkingBeatmap(BeatmapInfo beatmapInfo = null, ArchiveReader reader = null)
+        public WorkingBeatmap(Beatmap beatmap)
+        {
+            this.beatmap = beatmap;
+        }
+
+        public WorkingBeatmap(BeatmapInfo beatmapInfo, BeatmapSetInfo beatmapSetInfo, BeatmapDatabase database)
         {
             this.BeatmapInfo = beatmapInfo;
-            Reader = reader;
+            this.BeatmapSetInfo = beatmapSetInfo;
+            this.database = database;
         }
 
         private bool isDisposed;
@@ -68,7 +77,7 @@ namespace osu.Game.Beatmaps
             if (!isDisposed)
             {
                 track?.Dispose();
-                Reader?.Dispose();
+                reader?.Dispose();
                 isDisposed = true;
             }
         }
diff --git a/osu.Game/Database/BeatmapDatabase.cs b/osu.Game/Database/BeatmapDatabase.cs
index bb98daf6bc..06007dba9c 100644
--- a/osu.Game/Database/BeatmapDatabase.cs
+++ b/osu.Game/Database/BeatmapDatabase.cs
@@ -149,12 +149,10 @@ namespace osu.Game.Database
             if (beatmapSetInfo == null)
                 throw new InvalidOperationException($@"Beatmap set {beatmapInfo.BeatmapSetID} is not in the local database.");
 
-            var reader = GetReader(beatmapSetInfo);
-
             if (beatmapInfo.Metadata == null)
                 beatmapInfo.Metadata = beatmapSetInfo.Metadata;
 
-            var working = new WorkingBeatmap(beatmapInfo, reader);
+            var working = new WorkingBeatmap(beatmapInfo, beatmapSetInfo, this);
 
             previous?.TransferTo(working);