Fix a bug where an error change any permissions would cause the operation to fail and other files to not be changed

Author: cgutman

src/com/limelight/binding/input/evdev/EvdevReader.java

@@ -12,16 +12,16 @@ public class EvdevReader {
 	}
 
 	// Requires root to chmod /dev/input/eventX
-	public static boolean setPermissions(int octalPermissions) {
-		String chmodString = String.format("chmod %o /dev/input/*\n", octalPermissions);
-		
+	public static boolean setPermissions(String[] files, int octalPermissions) {		
 		ProcessBuilder builder = new ProcessBuilder("su");
 
 		try {
 			Process p = builder.start();
 
 			OutputStream stdin = p.getOutputStream();
-			stdin.write(chmodString.getBytes("UTF-8"));
+			for (String file : files) {
+				stdin.write(String.format("chmod %o %s\n", octalPermissions, file).getBytes("UTF-8"));
+			}
 			stdin.write("exit\n".getBytes("UTF-8"));
 			stdin.flush();
 

src/com/limelight/binding/input/evdev/EvdevWatcher.java

@@ -38,7 +38,7 @@ public void onEvent(int event, String fileName) {
 
 					if (!init) {
 						// If this a real new device, update permissions again so we can read it
-						EvdevReader.setPermissions(0666);
+						EvdevReader.setPermissions(new String[]{PATH + "/" + fileName}, 0666);
 					}
 
 					EvdevHandler handler = new EvdevHandler(PATH + "/" + fileName, listener);
@@ -63,17 +63,29 @@ public EvdevWatcher(EvdevListener listener) {
 		this.listener = listener;
 	}
 
+	private File[] rundownWithPermissionsChange(int newPermissions) {
+		// Rundown existing files
+		File devInputDir = new File(PATH);
+		File[] files = devInputDir.listFiles();
+		
+		// Set desired permissions
+		String[] filePaths = new String[files.length];
+		for (int i = 0; i < files.length; i++) {
+			filePaths[i] = files[i].getAbsolutePath();
+		}
+		EvdevReader.setPermissions(filePaths, newPermissions);
+		
+		return files;
+	}
+	
 	public void start() {
 		startThread = new Thread() {
 			@Override
 			public void run() {
-				// Get permissions to read the eventX files
-				EvdevReader.setPermissions(0666);
-				init = true;
+				// List all files and allow us access
+				File[] files = rundownWithPermissionsChange(0666);
 
-				// Rundown existing files and generate synthetic events
-				File devInputDir = new File(PATH);
-				File[] files = devInputDir.listFiles();
+				init = true;
 				for (File f : files) {
 					observer.onEvent(FileObserver.CREATE, f.getName());
 				}
@@ -92,7 +104,7 @@ public void run() {
 				}
 
 				// Giveup eventX permissions
-				EvdevReader.setPermissions(0066);
+				rundownWithPermissionsChange(066);
 			}
 		};
 		startThread.start();