copy xattr

helix-loader/src/lib.rs

@@ -136,7 +136,7 @@ pub fn state_dir() -> PathBuf {
     #[cfg(unix)]
     {
         let strategy = choose_base_strategy().expect("Unable to find the state directory!");
-        let mut path = strategy.state_dir();
+        let mut path = strategy.state_dir().unwrap();
         path.push("helix");
         path
     }

helix-stdx/src/faccess.rs

@@ -54,20 +54,6 @@ mod imp {
         Ok(())
     }
 
-    pub fn chown(p: &Path, uid: Option<u32>, gid: Option<u32>) -> io::Result<()> {
-        let uid = uid.map(|n| unsafe { rustix::fs::Uid::from_raw(n) });
-        let gid = gid.map(|n| unsafe { rustix::fs::Gid::from_raw(n) });
-        rustix::fs::chown(p, uid, gid)?;
-        Ok(())
-    }
-
-    pub fn fchown(fd: impl AsFd, uid: Option<u32>, gid: Option<u32>) -> io::Result<()> {
-        let uid = uid.map(|n| unsafe { rustix::fs::Uid::from_raw(n) });
-        let gid = gid.map(|n| unsafe { rustix::fs::Gid::from_raw(n) });
-        rustix::fs::fchown(fd, uid, gid)?;
-        Ok(())
-    }
-
     pub fn copy_metadata(from: &Path, to: &Path) -> io::Result<()> {
         let from_meta = std::fs::metadata(from)?;
         let to_meta = std::fs::metadata(to)?;
@@ -547,6 +533,73 @@ pub fn copy_ownership(from: &Path, to: &Path) -> io::Result<()> {
     imp::copy_ownership(from, to)
 }
 
+#[cfg(unix)]
+pub fn chown(p: &Path, uid: Option<u32>, gid: Option<u32>) -> io::Result<()> {
+    let uid = uid.map(|n| unsafe { rustix::fs::Uid::from_raw(n) });
+    let gid = gid.map(|n| unsafe { rustix::fs::Gid::from_raw(n) });
+    rustix::fs::chown(p, uid, gid)?;
+    Ok(())
+}
+
+#[cfg(unix)]
+pub fn fchown(fd: impl std::os::fd::AsFd, uid: Option<u32>, gid: Option<u32>) -> io::Result<()> {
+    let uid = uid.map(|n| unsafe { rustix::fs::Uid::from_raw(n) });
+    let gid = gid.map(|n| unsafe { rustix::fs::Gid::from_raw(n) });
+    rustix::fs::fchown(fd, uid, gid)?;
+    Ok(())
+}
+
+#[cfg(unix)]
+pub fn copy_xattr(from: &Path, to: &Path) -> io::Result<()> {
+    let size = match rustix::fs::listxattr(from, &mut [])? {
+        0 => return Ok(()), // No attributes
+        len => len,
+    };
+
+    let mut buf = vec![0i8; size];
+    let read = rustix::fs::listxattr(from, &mut buf)?;
+
+    fn i8_to_u8_slice(input: &[i8]) -> &[u8] {
+        // SAFETY: Simply reinterprets bytes
+        unsafe { std::slice::from_raw_parts(input.as_ptr() as *const u8, input.len()) }
+    }
+
+    // Iterate over null-terminated C-style strings
+    // Two loops to avoid multiple allocations
+    // Find max-size for attributes
+    let mut max_attr_len = 0;
+    for attr_byte in buf.split(|&b| b == 0) {
+        let name = std::str::from_utf8(i8_to_u8_slice(attr_byte))
+            .map_err(|_| std::io::Error::from(std::io::ErrorKind::InvalidData))?;
+        let attr_len = rustix::fs::getxattr(from, name, &mut [])?;
+        max_attr_len = max_attr_len.max(attr_len);
+    }
+
+    let mut attr_buf = vec![0u8; max_attr_len];
+    for attr_byte in buf.split(|&b| b == 0) {
+        let name = std::str::from_utf8(i8_to_u8_slice(attr_byte))
+            .map_err(|_| std::io::Error::from(std::io::ErrorKind::InvalidData))?;
+        let read = rustix::fs::getxattr(from, name, &mut attr_buf)?;
+
+        // If we can't set xattr because it already exists, try to replace it
+        if read != 0 {
+            match rustix::fs::setxattr(to, name, &attr_buf[..read], rustix::fs::XattrFlags::CREATE)
+            {
+                Err(rustix::io::Errno::EXIST) => rustix::fs::setxattr(
+                    to,
+                    name,
+                    &attr_buf[..read],
+                    rustix::fs::XattrFlags::REPLACE,
+                )?,
+                Err(e) => return Err(e.into()),
+                _ => {}
+            }
+        }
+    }
+
+    Ok(())
+}
+
 /*
 Neovim backup path function:
 - If a backup is desired (would be disabled by a user if using a file watcher):

helix-view/src/document.rs

@@ -23,6 +23,7 @@ use std::collections::HashMap;
 use std::fmt::Display;
 use std::future::Future;
 use std::io;
+use std::os::unix::fs::MetadataExt;
 use std::path::{Path, PathBuf};
 use std::str::FromStr;
 use std::sync::{Arc, Weak};
@@ -169,6 +170,27 @@ impl Backup {
                 // builder.permissions()
                 if let Ok(f) = builder.tempfile() {
                     // Check if we have perms to set perms
+                    #[cfg(unix)]
+                    {
+                        use std::os::{fd::AsFd, unix::fs::MetadataExt};
+
+                        let from_meta = tokio::fs::metadata(&p).await?;
+                        let to_meta = tokio::fs::metadata(&f.path()).await?;
+                        let _ = fchown(
+                            f.as_file().as_fd(),
+                            Some(from_meta.uid()),
+                            Some(from_meta.gid()),
+                        );
+
+                        if from_meta.uid() != to_meta.uid()
+                            || from_meta.gid() != to_meta.gid()
+                            || from_meta.permissions() != to_meta.permissions()
+                        {
+                            copy = true;
+                        }
+                    }
+
+                    #[cfg(not(unix))]
                     if copy_metadata(&p, f.path()).is_err() {
                         copy = true;
                     }
@@ -209,23 +231,26 @@ impl Backup {
 
                 #[cfg(unix)]
                 {
-                    let mut meta = tokio::fs::metadata(&p).await?;
-                    let mut perms = meta.permissions();
+                    use std::os::unix::fs::{MetadataExt, PermissionsExt};
+
+                    let mut from_meta = tokio::fs::metadata(&p).await?;
+                    let mut perms = from_meta.permissions();
 
                     // Strip s-bit
                     perms.set_mode(perms.mode() & 0o0777);
 
+                    let to_meta = tokio::fs::metadata(&backup).await?;
                     let from_gid = from_meta.gid();
                     let to_gid = to_meta.gid();
 
                     // If chown fails, se the protection bits for the roup the same as the perm bits for others
-                    if from_gid != to_gid && chown(to, None, Some(from_gid)).is_err() {
+                    if from_gid != to_gid && chown(&backup, None, Some(from_gid)).is_err() {
                         let new_perms = (perms.mode() & 0o0707) | ((perms.mode() & 0o07) << 3);
                         perms.set_mode(new_perms);
                     }
                     std::fs::set_permissions(&backup, perms)?;
                     // TODO: Set time
-                    // TODO: set xattr via rustix
+                    copy_xattr(&p, &backup)?;
                 }
 
                 #[cfg(windows)]
@@ -1080,6 +1105,7 @@ impl Document {
 
                     #[cfg(unix)]
                     {
+                        use std::os::unix::fs::PermissionsExt;
                         let mode = from_meta.permissions().mode();
                         open_opt.mode(mode);
                     }