refactor(tvix/store): use bytes for node names and symlink targets r/6436

Some paths might use names that are not valid UTF-8. We should be able
to represent them.

We don't actually need to touch the PathInfo structures, as they need to
represent StorePaths, which come with their own harder restrictions,
which can't encode non-UTF8 data.

While this doesn't change any of the wire format of the gRPC messages,
it does however change the interface of tvix_eval::EvalIO - its
read_dir() method does now return a list of Vec<u8>, rather than
SmolStr. Maybe this should be OsString instead?

Change-Id: I821016d9a58ec441ee081b0b9f01c9240723af0b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8974
Autosubmit: flokli <flokli@flokli.de>
Reviewed-by: raitobezarius <tvl@lahfa.xyz>
Tested-by: BuildkiteCI

1 files changed, 43 insertions, 40 deletions

diff --git a/tvix/store/src/proto/mod.rs b/tvix/store/src/proto/mod.rs
index 7e69726632..7e81efc517 100644
--- a/tvix/store/src/proto/mod.rs
+++ b/tvix/store/src/proto/mod.rs
@@ -1,6 +1,5 @@
 #![allow(clippy::derive_partial_eq_without_eq)]
 // https://github.com/hyperium/tonic/issues/1056
-use std::str::FromStr;
 use std::{collections::HashSet, iter::Peekable};
 use thiserror::Error;
 
@@ -35,14 +34,14 @@ mod tests;
 #[derive(Debug, PartialEq, Eq, Error)]
 pub enum ValidateDirectoryError {
     /// Elements are not in sorted order
-    #[error("{0} is not sorted")]
-    WrongSorting(String),
+    #[error("{0:?} is not sorted")]
+    WrongSorting(Vec<u8>),
     /// Multiple elements with the same name encountered
-    #[error("{0} is a duplicate name")]
-    DuplicateName(String),
+    #[error("{0:?} is a duplicate name")]
+    DuplicateName(Vec<u8>),
     /// Invalid name encountered
-    #[error("Invalid name in {0}")]
-    InvalidName(String),
+    #[error("Invalid name in {0:?}")]
+    InvalidName(Vec<u8>),
     /// Invalid digest length encountered
     #[error("Invalid Digest length: {0}")]
     InvalidDigestLen(usize),
@@ -56,8 +55,8 @@ pub enum ValidatePathInfoError {
     NoNodePresent(),
 
     /// Invalid node name encountered.
-    #[error("Failed to parse {0} as StorePath: {1}")]
-    InvalidNodeName(String, store_path::Error),
+    #[error("Failed to parse {0:?} as StorePath: {1}")]
+    InvalidNodeName(Vec<u8>, store_path::Error),
 
     /// The digest the (root) node refers to has invalid length.
     #[error("Invalid Digest length: {0}")]
@@ -73,10 +72,14 @@ pub enum ValidatePathInfoError {
 /// error that's generated from the supplied constructor.
 ///
 /// We disallow slashes, null bytes, '.', '..' and the empty string.
-fn validate_node_name<E>(name: &str, err: fn(String) -> E) -> Result<(), E> {
-    if name.is_empty() || name == ".." || name == "." || name.contains('\x00') || name.contains('/')
+fn validate_node_name<E>(name: &[u8], err: fn(Vec<u8>) -> E) -> Result<(), E> {
+    if name.is_empty()
+        || name == b".."
+        || name == b"."
+        || name.contains(&0x00)
+        || name.contains(&b'/')
     {
-        return Err(err(name.to_string()));
+        return Err(err(name.to_vec()));
     }
     Ok(())
 }
@@ -95,12 +98,12 @@ fn validate_digest<E>(digest: &Vec<u8>, err: fn(usize) -> E) -> Result<(), E> {
 /// On success, this returns the parsed [StorePath].
 /// On error, it returns an error generated from the supplied constructor.
 fn parse_node_name_root<E>(
-    name: &str,
-    err: fn(String, store_path::Error) -> E,
+    name: &[u8],
+    err: fn(Vec<u8>, store_path::Error) -> E,
 ) -> Result<StorePath, E> {
-    match StorePath::from_str(name) {
+    match StorePath::from_bytes(name) {
         Ok(np) => Ok(np),
-        Err(e) => Err(err(name.to_string(), e)),
+        Err(e) => Err(err(name.to_vec(), e)),
     }
 }
 
@@ -169,29 +172,29 @@ impl PathInfo {
 /// NamedNode is implemented for [FileNode], [DirectoryNode] and [SymlinkNode]
 /// and [node::Node], so we can ask all of them for the name easily.
 pub trait NamedNode {
-    fn get_name(&self) -> &str;
+    fn get_name(&self) -> &[u8];
 }
 
 impl NamedNode for &FileNode {
-    fn get_name(&self) -> &str {
-        self.name.as_str()
+    fn get_name(&self) -> &[u8] {
+        &self.name
     }
 }
 
 impl NamedNode for &DirectoryNode {
-    fn get_name(&self) -> &str {
-        self.name.as_str()
+    fn get_name(&self) -> &[u8] {
+        &self.name
     }
 }
 
 impl NamedNode for &SymlinkNode {
-    fn get_name(&self) -> &str {
-        self.name.as_str()
+    fn get_name(&self) -> &[u8] {
+        &self.name
     }
 }
 
 impl NamedNode for node::Node {
-    fn get_name(&self) -> &str {
+    fn get_name(&self) -> &[u8] {
         match self {
             node::Node::File(node_file) => &node_file.name,
             node::Node::Directory(node_directory) => &node_directory.name,
@@ -204,11 +207,11 @@ impl NamedNode for node::Node {
 /// If the passed name is larger than the previous one, the reference is updated.
 /// If it's not, an error is returned.
 fn update_if_lt_prev<'n>(
-    prev_name: &mut &'n str,
-    name: &'n str,
+    prev_name: &mut &'n [u8],
+    name: &'n [u8],
 ) -> Result<(), ValidateDirectoryError> {
     if *name < **prev_name {
-        return Err(ValidateDirectoryError::WrongSorting(name.to_string()));
+        return Err(ValidateDirectoryError::WrongSorting(name.to_vec()));
     }
     *prev_name = name;
     Ok(())
@@ -217,11 +220,11 @@ fn update_if_lt_prev<'n>(
 /// Inserts the given name into a HashSet if it's not already in there.
 /// If it is, an error is returned.
 fn insert_once<'n>(
-    seen_names: &mut HashSet<&'n str>,
-    name: &'n str,
+    seen_names: &mut HashSet<&'n [u8]>,
+    name: &'n [u8],
 ) -> Result<(), ValidateDirectoryError> {
     if seen_names.get(name).is_some() {
-        return Err(ValidateDirectoryError::DuplicateName(name.to_string()));
+        return Err(ValidateDirectoryError::DuplicateName(name.to_vec()));
     }
     seen_names.insert(name);
     Ok(())
@@ -258,11 +261,11 @@ impl Directory {
     /// - not properly sorted lists
     /// - duplicate names in the three lists
     pub fn validate(&self) -> Result<(), ValidateDirectoryError> {
-        let mut seen_names: HashSet<&str> = HashSet::new();
+        let mut seen_names: HashSet<&[u8]> = HashSet::new();
 
-        let mut last_directory_name: &str = "";
-        let mut last_file_name: &str = "";
-        let mut last_symlink_name: &str = "";
+        let mut last_directory_name: &[u8] = b"";
+        let mut last_file_name: &[u8] = b"";
+        let mut last_symlink_name: &[u8] = b"";
 
         // check directories
         for directory_node in &self.directories {
@@ -272,8 +275,8 @@ impl Directory {
                 ValidateDirectoryError::InvalidDigestLen,
             )?;
 
-            update_if_lt_prev(&mut last_directory_name, directory_node.name.as_str())?;
-            insert_once(&mut seen_names, directory_node.name.as_str())?;
+            update_if_lt_prev(&mut last_directory_name, &directory_node.name)?;
+            insert_once(&mut seen_names, &directory_node.name)?;
         }
 
         // check files
@@ -281,16 +284,16 @@ impl Directory {
             validate_node_name(&file_node.name, ValidateDirectoryError::InvalidName)?;
             validate_digest(&file_node.digest, ValidateDirectoryError::InvalidDigestLen)?;
 
-            update_if_lt_prev(&mut last_file_name, file_node.name.as_str())?;
-            insert_once(&mut seen_names, file_node.name.as_str())?;
+            update_if_lt_prev(&mut last_file_name, &file_node.name)?;
+            insert_once(&mut seen_names, &file_node.name)?;
         }
 
         // check symlinks
         for symlink_node in &self.symlinks {
             validate_node_name(&symlink_node.name, ValidateDirectoryError::InvalidName)?;
 
-            update_if_lt_prev(&mut last_symlink_name, symlink_node.name.as_str())?;
-            insert_once(&mut seen_names, symlink_node.name.as_str())?;
+            update_if_lt_prev(&mut last_symlink_name, &symlink_node.name)?;
+            insert_once(&mut seen_names, &symlink_node.name)?;
         }
 
         Ok(())