Handle receiving an empty file

Summary:
When an empty file is send from the desktop SharePlugin onPacketReceived
does not see a payload so the packet is discarded

Test Plan:
Send an empty file from the desktop
Verify that a notification is shown notifying the user that a file was received and that file has been created in the filesystem

Reviewers: #kde_connect, albertvaka

Reviewed By: #kde_connect, albertvaka

Subscribers: nicolasfella, kdeconnect

Tags: #kde_connect

Differential Revision: https://phabricator.kde.org/D17235

res/values/strings.xml

@@ -150,6 +150,7 @@
         <item quantity="other">Failed receiving %1$d of %2$d files from %3$s</item>
     </plurals>
     <string name="received_file_text">Tap to open \'%1s\'</string>
+    <string name="cannot_create_file">Cannot create file %s</string>
     <string name="sent_file_title">Sent file to %1s</string>
     <string name="sent_file_text">%1s</string>
     <string name="sent_file_failed_title">Failed to send file to %1s</string>

src/org/kde/kdeconnect/Plugins/SharePlugin/SharePlugin.java

@@ -127,7 +127,7 @@ public class SharePlugin extends Plugin implements ReceiveFileRunnable.CallBack
     @WorkerThread
     public boolean onPacketReceived(NetworkPacket np) {
         try {
-            if (np.hasPayload()) {
+            if (np.has("filename")) {
                 if (isPermissionGranted(Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
                     receiveFile(np);
                 } else {
@@ -242,7 +242,20 @@ public class SharePlugin extends Plugin implements ReceiveFileRunnable.CallBack
 
         info.fileDocument = destinationFolderDocument.createFile(mimeType, displayName);
         assert info.fileDocument != null;
-        info.fileDocument.getType();
+
+        if (shareNotification == null) {
+            shareNotification = new ShareNotification(device);
+        }
+
+        if (info.fileDocument == null) {
+            onError(info, new RuntimeException(context.getString(R.string.cannot_create_file, filename)));
+            return;
+        }
+
+        shareNotification.setTitle(context.getResources().getQuantityString(R.plurals.incoming_file_title, info.numberOfFiles(), info.numberOfFiles(), device.getName()));
+        shareNotification.show();
+
+        if (np.hasPayload()) {
             try {
                 info.outputStream = new BufferedOutputStream(context.getContentResolver().openOutputStream(info.fileDocument.getUri()));
             } catch (FileNotFoundException e) {
@@ -250,16 +263,12 @@ public class SharePlugin extends Plugin implements ReceiveFileRunnable.CallBack
                 return;
             }
 
-        if (shareNotification == null) {
-            shareNotification = new ShareNotification(device);
-        }
-
-        shareNotification.setTitle(context.getResources().getQuantityString(R.plurals.incoming_file_title, info.numberOfFiles(), info.numberOfFiles(), device.getName()));
-        //shareNotification.setProgress(0, context.getResources().getQuantityString(R.plurals.incoming_files_text, numFiles, filename, currentFileNum, numFiles));
-        shareNotification.show();
-
             ReceiveFileRunnable runnable = new ReceiveFileRunnable(info, this);
             executorService.execute(runnable);
+        } else {
+            onProgress(info, 100);
+            onSuccess(info);
+        }
     }
 
     @Override
@@ -498,6 +507,7 @@ public class SharePlugin extends Plugin implements ReceiveFileRunnable.CallBack
 
         info.fileDocument.delete();
 
+        //TODO: Show error in notification
         int failedFiles = info.numberOfFiles() - (info.currentFileNumber - 1);
         shareNotification.setFinished(context.getResources().getQuantityString(R.plurals.received_files_fail_title, failedFiles, failedFiles, info.numberOfFiles(), device.getName()));
         shareNotification.show();