src: increase use of Self where possible

Various bits of code here predate my having learned what Self.  We're
about to throw a bunch of generic type arguments absolutely everywhere,
so increase our use of Self first to help make that less painful.

Signed-off-by: Allison Karlitskaya <[email protected]>

Author: allisonkarlitskaya

src/fs.rs

@@ -176,7 +176,7 @@ impl FilesystemReader<'_> {
                 st_uid: buf.st_uid,
                 st_gid: buf.st_gid,
                 st_mtim_sec: buf.st_mtime as i64,
-                xattrs: RefCell::new(FilesystemReader::read_xattrs(fd)?),
+                xattrs: RefCell::new(Self::read_xattrs(fd)?),
             },
         ))
     }
@@ -225,7 +225,7 @@ impl FilesystemReader<'_> {
             Mode::empty(),
         )?;
 
-        let (buf, stat) = FilesystemReader::stat(&fd, ifmt)?;
+        let (buf, stat) = Self::stat(&fd, ifmt)?;
 
         // NB: We could check `st_nlink > 1` to find out if we should track a file as a potential
         // hardlink or not, but some filesystems (like fuse-overlayfs) can report this incorrectly.
@@ -249,7 +249,7 @@ impl FilesystemReader<'_> {
             Mode::empty(),
         )?;
 
-        let (_, stat) = FilesystemReader::stat(&fd, FileType::Directory)?;
+        let (_, stat) = Self::stat(&fd, FileType::Directory)?;
         let mut directory = Directory::new(stat);
 
         for item in Dir::read_from(&fd)? {

src/repository.rs

@@ -46,7 +46,7 @@ impl Repository {
         )
     }
 
-    pub fn open_path(dirfd: impl AsFd, path: impl AsRef<Path>) -> Result<Repository> {
+    pub fn open_path(dirfd: impl AsFd, path: impl AsRef<Path>) -> Result<Self> {
         let path = path.as_ref();
 
         // O_PATH isn't enough because flock()
@@ -56,17 +56,17 @@ impl Repository {
         flock(&repository, FlockOperation::LockShared)
             .context("Cannot lock composefs repository")?;
 
-        Ok(Repository { repository })
+        Ok(Self { repository })
     }
 
-    pub fn open_user() -> Result<Repository> {
+    pub fn open_user() -> Result<Self> {
         let home = std::env::var("HOME").with_context(|| "$HOME must be set when in user mode")?;
 
-        Repository::open_path(CWD, PathBuf::from(home).join(".var/lib/composefs"))
+        Self::open_path(CWD, PathBuf::from(home).join(".var/lib/composefs"))
     }
 
-    pub fn open_system() -> Result<Repository> {
-        Repository::open_path(CWD, PathBuf::from("/sysroot/composefs".to_string()))
+    pub fn open_system() -> Result<Self> {
+        Self::open_path(CWD, PathBuf::from("/sysroot/composefs".to_string()))
     }
 
     fn ensure_dir(&self, dir: impl AsRef<Path>) -> ErrnoResult<()> {
@@ -212,7 +212,7 @@ impl Repository {
         };
         let stream_path = format!("streams/{}", hex::encode(sha256));
         let object_id = writer.done()?;
-        let object_path = Repository::format_object_path(&object_id);
+        let object_path = Self::format_object_path(&object_id);
         self.ensure_symlink(&stream_path, &object_path)?;
 
         if let Some(name) = reference {
@@ -261,7 +261,7 @@ impl Repository {
                 callback(&mut writer)?;
                 let object_id = writer.done()?;
 
-                let object_path = Repository::format_object_path(&object_id);
+                let object_path = Self::format_object_path(&object_id);
                 self.ensure_symlink(&stream_path, &object_path)?;
                 object_id
             }
@@ -411,11 +411,11 @@ impl Repository {
                     let filename = entry.file_name();
                     if filename != c"." && filename != c".." {
                         let dirfd = openat(&fd, filename, OFlags::RDONLY, Mode::empty())?;
-                        Repository::walk_symlinkdir(dirfd, objects)?;
+                        Self::walk_symlinkdir(dirfd, objects)?;
                     }
                 }
                 FileType::Symlink => {
-                    objects.insert(Repository::read_symlink_hashvalue(&fd, entry.file_name())?);
+                    objects.insert(Self::read_symlink_hashvalue(&fd, entry.file_name())?);
                 }
                 _ => {
                     bail!("Unexpected file type encountered");
@@ -447,7 +447,7 @@ impl Repository {
             OFlags::RDONLY | OFlags::DIRECTORY,
             Mode::empty(),
         )?;
-        Repository::walk_symlinkdir(refs, &mut objects)?;
+        Self::walk_symlinkdir(refs, &mut objects)?;
 
         for item in Dir::read_from(&category_fd)? {
             let entry = item?;

src/splitstream.rs

@@ -78,12 +78,12 @@ impl std::fmt::Debug for SplitStreamWriter<'_> {
     }
 }
 
-impl SplitStreamWriter<'_> {
+impl<'a> SplitStreamWriter<'a> {
     pub fn new(
-        repo: &Repository,
+        repo: &'a Repository,
         refs: Option<DigestMap>,
         sha256: Option<Sha256Digest>,
-    ) -> SplitStreamWriter {
+    ) -> Self {
         // SAFETY: we surely can't get an error writing the header to a Vec<u8>
         let mut writer = Encoder::new(vec![], 0).unwrap();
 
@@ -97,7 +97,7 @@ impl SplitStreamWriter<'_> {
             }
         }
 
-        SplitStreamWriter {
+        Self {
             repo,
             inline_content: vec![],
             writer,
@@ -113,7 +113,7 @@ impl SplitStreamWriter<'_> {
     /// flush any buffered inline data, taking new_value as the new value of the buffer
     fn flush_inline(&mut self, new_value: Vec<u8>) -> Result<()> {
         if !self.inline_content.is_empty() {
-            SplitStreamWriter::write_fragment(
+            Self::write_fragment(
                 &mut self.writer,
                 self.inline_content.len(),
                 &self.inline_content,
@@ -140,7 +140,7 @@ impl SplitStreamWriter<'_> {
         // external data becomes the start of a new inline block.
         self.flush_inline(padding)?;
 
-        SplitStreamWriter::write_fragment(&mut self.writer, 0, reference.as_bytes())
+        Self::write_fragment(&mut self.writer, 0, reference.as_bytes())
     }
 
     pub fn write_external(&mut self, data: &[u8], padding: Vec<u8>) -> Result<()> {
@@ -214,7 +214,7 @@ enum ChunkType {
 }
 
 impl<R: Read> SplitStreamReader<R> {
-    pub fn new(reader: R) -> Result<SplitStreamReader<R>> {
+    pub fn new(reader: R) -> Result<Self> {
         let mut decoder = Decoder::new(reader)?;
 
         let n_map_entries = {
@@ -230,7 +230,7 @@ impl<R: Read> SplitStreamReader<R> {
             refs.map.push(DigestMapEntry::read_from_io(&mut decoder)?);
         }
 
-        Ok(SplitStreamReader {
+        Ok(Self {
             decoder,
             refs,
             inline_bytes: 0,