Fix a crash when encountering 0 byte .vqa placeholders.

OpenRA.Mods.Cnc/VideoLoaders/VqaLoader.cs

@@ -21,6 +21,9 @@ namespace OpenRA.Mods.Cnc.VideoLoaders
 		{
 			video = null;
 
+			if (s.Length == 0)
+				return false;
+
 			if (!IsWestwoodVqa(s))
 				return false;
 
@@ -28,7 +31,7 @@ namespace OpenRA.Mods.Cnc.VideoLoaders
 			return true;
 		}
 
-		bool IsWestwoodVqa(Stream s)
+		static bool IsWestwoodVqa(Stream s)
 		{
 			var start = s.Position;
 

OpenRA.Mods.Cnc/VideoLoaders/WsaLoader.cs

@@ -22,6 +22,9 @@ namespace OpenRA.Mods.Cnc.VideoLoaders
 		{
 			video = null;
 
+			if (s.Length == 0)
+				return false;
+
 			if (!IsWsa(s))
 				return false;
 
@@ -29,7 +32,7 @@ namespace OpenRA.Mods.Cnc.VideoLoaders
 			return true;
 		}
 
-		bool IsWsa(Stream s)
+		static bool IsWsa(Stream s)
 		{
 			var start = s.Position;
 

OpenRA.Mods.Common/Scripting/Global/MediaGlobal.cs

@@ -170,7 +170,7 @@ namespace OpenRA.Mods.Common.Scripting
 			}
 			catch (FileNotFoundException e)
 			{
-				Log.Write("lua", "Couldn't play movie {0}! File doesn't exist.", e.FileName);
+				Log.Write("lua", $"Couldn't play movie {e.FileName}! File doesn't exist.");
 				onCompleteRadar();
 				return false;
 			}

OpenRA.Mods.Common/Widgets/Logic/MissionBrowserLogic.cs

@@ -343,6 +343,18 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 				playingVideo = pv;
 				player.Load(video);
 
+				if (player.Video == null)
+				{
+					StopVideo(player);
+
+					ConfirmationDialogs.ButtonPrompt(
+						title: "Unable to play video",
+						text: "Something went wrong during video playback.",
+						cancelText: "Back",
+						onCancel: () => { });
+				}
+				else
+				{
 					// video playback runs asynchronously
 					player.PlayThen(() =>
 					{
@@ -354,6 +366,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 					MuteSounds();
 				}
 			}
+		}
 
 		void StopVideo(VideoPlayerWidget player)
 		{

OpenRA.Mods.Common/Widgets/VideoPlayerWidget.cs

@@ -46,7 +46,8 @@ namespace OpenRA.Mods.Common.Widgets
 			if (filename == cachedVideoFileName)
 				return;
 
-			var video = VideoLoader.GetVideo(Game.ModData.DefaultFileSystem.Open(filename), true, Game.ModData.VideoLoaders);
+			var stream = Game.ModData.DefaultFileSystem.Open(filename);
+			var video = VideoLoader.GetVideo(stream, true, Game.ModData.VideoLoaders);
 			Open(video);
 
 			cachedVideoFileName = filename;
@@ -56,6 +57,9 @@ namespace OpenRA.Mods.Common.Widgets
 		{
 			this.video = video;
 
+			if (video == null)
+				return;
+
 			stopped = true;
 			paused = true;
 			Game.Sound.StopVideo();