Make extracted ffmpeg executable

[jrb0001]

This also makes ./gradlew executable for easier building on linux.

[itdelatrisu]

Can you explain / can anyone else confirm? No one has reported this to be an issue and the feature has been out for a long time now.

[jrb0001]

Opsu failed to play background videos and the log showed stacktraces caused by the ffmpeg file not being executable.

[tpenguinltg]

Confirmed. I probably haven't noticed because I build using the system FFmpeg and turn videos off.

However, this patch isn't enough to fix the problem. The patch only covers the case when you're running the JAR and natives get extracted into the Natives directory, but not when running using gradle and there's already a build/natives directory present. The maven build (with target/natives) is probably affected, too but I've never been successful in building using maven (it's probably my setup).

Sun Feb 11 18:53:02 EST 2018 ERROR:Cannot run program "/scratch/opsu/./build/natives/ffmpeg64": error=13, Permission denied
java.io.IOException: Cannot run program "/scratch/opsu/./build/natives/ffmpeg64": error=13, Permission denied
        at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048)
        at itdelatrisu.opsu.video.FFmpeg.extractMetadata(FFmpeg.java:97)
        at itdelatrisu.opsu.video.Video.<init>(Video.java:80)
        at itdelatrisu.opsu.states.Game.loadVideo(Game.java:1976)
        at itdelatrisu.opsu.states.Game.enter(Game.java:1654)
        at org.newdawn.slick.state.StateBasedGame.update(StateBasedGame.java:248)
        at org.newdawn.slick.GameContainer.updateAndRender(GameContainer.java:702)
        at itdelatrisu.opsu.Container.gameLoop(Container.java:136)
        at itdelatrisu.opsu.Container.start(Container.java:80)
        at itdelatrisu.opsu.Opsu.main(Opsu.java:213)
Caused by: java.io.IOException: error=13, Permission denied
        at java.lang.UNIXProcess.forkAndExec(Native Method)
        at java.lang.UNIXProcess.<init>(UNIXProcess.java:247)
        at java.lang.ProcessImpl.start(ProcessImpl.java:134)
        at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029)
        ... 9 more

[itdelatrisu]

Is this solved by changing getNativeLocation() in FFmpeg.java to this?

private static File getNativeLocation() {
	File customLocation = Options.getFFmpegLocation();
	File f = (customLocation != null && customLocation.isFile()) ? customLocation : FFMPEG_PATH;
	if (!Files.isExecutable(f.toPath())) {
		f.setExecutable(true);
	}
	return f;
}

[tpenguinltg]

@itdelatrisu Yes, it appears so. I'm not so sure about stuffing it in that function as it would result in too many concerns, but I guess it's fine as long as you're okay with the side effect.

[itdelatrisu]

Committed in cd1cdf8, thanks!