fix case where the iterator recursion would blow the stack

src/patch/patch.rs

@@ -288,7 +288,6 @@ fn does_file_need_updating(file_info: &FileInfoReply, patch_file_lookup: &HashMa
 struct SendFileIterator {
     done: bool,
     file_iter: Box<dyn Iterator<Item = PatchTreeIterItem>>,
-    file_ids_to_update: HashSet<u32>,
     patch_file_lookup: HashMap<u32, PatchFile>,
     current_file: Option<io::BufReader<fs::File>>,
     chunk_num: u32,
@@ -303,9 +302,15 @@ impl SendFileIterator {
 
         SendFileIterator {
             done: false,
-            file_ids_to_update: file_ids_to_update,
             patch_file_lookup: state.patch_file_lookup.clone(),
-            file_iter: Box::new(state.patch_file_tree.flatten().into_iter()),
+            file_iter: Box::new(state.patch_file_tree.flatten().into_iter().filter(move |file| {
+                match file {
+                    PatchTreeIterItem::File(path, id) => {
+                        file_ids_to_update.contains(&id)
+                    },
+                    _ => true,
+                }
+            })),
             current_file: None,
             chunk_num: 0,
         }
@@ -350,16 +355,11 @@ impl Iterator for SendFileIterator {
                                 Some(SendPatchPacket::ChangeDirectory(ChangeDirectory::new(path.to_str().unwrap())))
                             },
                             PatchTreeIterItem::File(path, id) => {
-                                if self.file_ids_to_update.contains(&id) {
                                 let patch_file = self.patch_file_lookup.get(&id).unwrap();
                                 let file = fs::File::open(&patch_file.path).unwrap();
                                 let size = file.metadata().unwrap().len();
                                 self.current_file = Some(io::BufReader::new(file));
                                 Some(SendPatchPacket::StartFileSend(StartFileSend::new(path.to_str().unwrap(), size as u32, id)))
-                                }
-                                else {
-                                    self.next()
-                                }
                             },
                             PatchTreeIterItem::UpDirectory => {
                                 Some(SendPatchPacket::UpOneDirectory(UpOneDirectory {}))