Merge pull request #1228 from cyqsimon/upload-refactor

Minor refactor on upload code

1 files changed, 84 insertions, 0 deletions

diff --git a/src/file_utils.rs b/src/file_utils.rs
new file mode 100644
index 0000000..114a08f
--- /dev/null
+++ b/src/file_utils.rs
@@ -0,0 +1,84 @@
+use std::{
+    io,
+    path::{Component, Path, PathBuf},
+};
+
+/// Guarantee that the path is relative and cannot traverse back to parent directories
+/// and optionally prevent traversing hidden directories.
+///
+/// See the unit tests tests::test_sanitize_path* for examples
+pub fn sanitize_path(path: impl AsRef<Path>, traverse_hidden: bool) -> Option<PathBuf> {
+    let mut buf = PathBuf::new();
+
+    for comp in path.as_ref().components() {
+        match comp {
+            Component::Normal(name) => buf.push(name),
+            Component::ParentDir => {
+                buf.pop();
+            }
+            _ => (),
+        }
+    }
+
+    // Double-check that all components are Normal and check for hidden dirs
+    for comp in buf.components() {
+        match comp {
+            Component::Normal(_) if traverse_hidden => (),
+            Component::Normal(name) if !name.to_str()?.starts_with('.') => (),
+            _ => return None,
+        }
+    }
+
+    Some(buf)
+}
+
+/// Checks if any segment of the path is a symlink.
+///
+/// This function fails if [`std::fs::symlink_metadata`] fails, which usually
+/// means user has no permission to access the path.
+pub fn contains_symlink(path: impl AsRef<Path>) -> io::Result<bool> {
+    let contains_symlink = path
+        .as_ref()
+        .ancestors()
+        // On Windows, `\\?\` won't exist even though it's the root, but there's no need to check it
+        // So we filter it out
+        .filter(|p| p.exists())
+        .map(|p| p.symlink_metadata())
+        .collect::<Result<Vec<_>, _>>()?
+        .into_iter()
+        .any(|p| p.file_type().is_symlink());
+
+    Ok(contains_symlink)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use pretty_assertions::assert_eq;
+    use rstest::rstest;
+
+    #[rstest]
+    #[case("/foo", "foo")]
+    #[case("////foo", "foo")]
+    #[case("C:/foo", if cfg!(windows) { "foo" } else { "C:/foo" })]
+    #[case("../foo", "foo")]
+    #[case("../foo/../bar/abc", "bar/abc")]
+    fn test_sanitize_path(#[case] input: &str, #[case] output: &str) {
+        assert_eq!(
+            sanitize_path(Path::new(input), true).unwrap(),
+            Path::new(output)
+        );
+        assert_eq!(
+            sanitize_path(Path::new(input), false).unwrap(),
+            Path::new(output)
+        );
+    }
+
+    #[rstest]
+    #[case(".foo")]
+    #[case("/.foo")]
+    #[case("foo/.bar/foo")]
+    fn test_sanitize_path_no_hidden_files(#[case] input: &str) {
+        assert_eq!(sanitize_path(Path::new(input), false), None);
+    }
+}