decoder/gme: use AtScopeExit()

src/decoder/plugins/GmeDecoderPlugin.cxx

@@ -25,6 +25,7 @@
 #include "tag/TagHandler.hxx"
 #include "fs/Path.hxx"
 #include "fs/AllocatedPath.hxx"
+#include "util/ScopeExit.hxx"
 #include "util/FormatString.hxx"
 #include "util/AllocatedString.hxx"
 #include "util/UriUtil.hxx"
@@ -141,6 +142,8 @@ gme_file_decode(Decoder &decoder, Path path_fs)
 		return;
 	}
 
+	AtScopeExit(emu) { gme_delete(emu); };
+
 	FormatDebug(gme_domain, "emulator type '%s'\n",
 		    gme_type_system(gme_type(emu)));
 
@@ -153,7 +156,6 @@ gme_file_decode(Decoder &decoder, Path path_fs)
 	gme_err = gme_track_info(emu, &ti, container.track);
 	if (gme_err != nullptr) {
 		LogWarning(gme_domain, gme_err);
-		gme_delete(emu);
 		return;
 	}
 
@@ -172,7 +174,6 @@ gme_file_decode(Decoder &decoder, Path path_fs)
 				       SampleFormat::S16, GME_CHANNELS,
 				       error)) {
 		LogError(error);
-		gme_delete(emu);
 		return;
 	}
 
@@ -209,8 +210,6 @@ gme_file_decode(Decoder &decoder, Path path_fs)
 		if (gme_track_ended(emu))
 			break;
 	} while (cmd != DecoderCommand::STOP);
-
-	gme_delete(emu);
 }
 
 static void