add dynlay

src/fs.rs

@@ -0,0 +1,60 @@
+use eyre::Result;
+use std::fs::Metadata;
+use std::path::PathBuf;
+use tokio::fs::read_dir;
+use tokio::sync::mpsc;
+
+pub fn spawn_walk_dir(
+    dir: impl Into<PathBuf> + Send + 'static,
+) -> mpsc::Receiver<Result<(PathBuf, Metadata)>> {
+    let (tx, rx) = mpsc::channel(1);
+    tokio::spawn(walk_dir(dir, tx));
+    rx
+}
+
+pub async fn walk_dir(dir: impl Into<PathBuf>, tx: mpsc::Sender<Result<(PathBuf, Metadata)>>) {
+    let dir: PathBuf = dir.into();
+
+    let mut todo = std::collections::LinkedList::new();
+    if let Ok(rd) = read_dir(&dir).await {
+        todo.push_front(rd);
+    }
+
+    while let Some(rd) = todo.front_mut() {
+        let entry = match rd.next_entry().await {
+            Ok(v) => v,
+            Err(e) => {
+                if tx.send(Err(e.into())).await.is_err() {
+                    return;
+                }
+                todo.pop_front(); // skip dir on error
+                continue;
+            }
+        };
+
+        let Some(entry) = entry else {
+            todo.pop_front();
+            continue;
+        };
+
+        let Ok(md) = entry.metadata().await else {
+            continue;
+        };
+        let is_dir = md.is_dir();
+
+        let Ok(path) = entry.path().strip_prefix(&dir).map(|p| p.to_path_buf()) else {
+            continue; // sub-entry not in dir, weird but semantically, we ignore
+        };
+
+        if tx.send(Ok((path, md))).await.is_err() {
+            return;
+        }
+
+        // recurse in sub directories
+        if is_dir {
+            if let Ok(rd) = read_dir(entry.path()).await {
+                todo.push_front(rd);
+            }
+        }
+    }
+}