remove system archive feature

Just compress the initrd with zstd.
Remove rsmount dependency, mtab is easy enough to parse.

src/cmd/init.rs

@@ -62,24 +62,6 @@ pub async fn run() {
         log::set_max_level(log::LevelFilter::Debug);
     }
 
-    // extract system archive
-    retry_or_ignore(async || {
-        if fs::try_exists("system.azstd").await? {
-            info!("unpacking system.azstd");
-            let zarch = fs::read("system.azstd").await?;
-            let arch = zstd::Decoder::new(zarch.as_slice())?;
-            extract_cpio(arch).await
-        } else if fs::try_exists("system.alz4").await? {
-            info!("unpacking system.alz4");
-            let zarch = fs::read("system.alz4").await?;
-            let arch = lz4::Decoder::new(zarch.as_slice())?;
-            extract_cpio(arch).await
-        } else {
-            Ok(())
-        }
-    })
-    .await;
-
     // load config
     let cfg: Config = retry(async || {
         let cfg = (fs::read("config.yaml").await)
@@ -190,72 +172,6 @@ async fn chmod(path: impl AsRef<Path>, mode: u32) -> std::io::Result<()> {
     fs::set_permissions(path, perms).await
 }
 
-async fn extract_cpio(mut arch: impl std::io::Read) -> Result<()> {
-    loop {
-        let rd = cpio::NewcReader::new(&mut arch)?;
-        let entry = rd.entry();
-        if entry.is_trailer() {
-            return Ok(());
-        }
-
-        let path = entry.name().to_string();
-
-        if let Err(e) = extract_cpio_entry(rd, &path).await {
-            return Err(format_err!("failed to extract {path}: {e}"));
-        }
-    }
-}
-
-async fn extract_cpio_entry<R: std::io::Read>(
-    rd: cpio::NewcReader<R>,
-    path: impl AsRef<Path>,
-) -> Result<()> {
-    use std::os::unix::fs::chown;
-    use unix_mode::Type;
-
-    let entry = rd.entry();
-    let path = path.as_ref();
-
-    if let Some(parent) = path.parent() {
-        fs::create_dir_all(parent).await?;
-    }
-
-    let _ = fs::remove_file(path).await;
-
-    let mode = entry.mode();
-    let uid = entry.uid();
-    let gid = entry.gid();
-
-    match Type::from(mode) {
-        Type::Dir => {
-            fs::create_dir_all(path).await?;
-        }
-        Type::File => {
-            let mut data = vec![];
-            rd.to_writer(&mut data)?;
-
-            fs::write(path, data).await?;
-        }
-        Type::Symlink => {
-            let mut data = vec![];
-            rd.to_writer(&mut data)?;
-            let target = &Path::new(std::str::from_utf8(&data)?);
-
-            tokio::fs::symlink(target, path).await?;
-            return Ok(());
-        }
-        _ => {
-            warn!("{path:?}: unknown file type: {:?}", Type::from(mode));
-            return Ok(());
-        }
-    }
-
-    chmod(path, mode).await?;
-    chown(path, Some(uid), Some(gid))?;
-
-    Ok(())
-}
-
 async fn mount(src: Option<&str>, dst: &str, fstype: &str, opts: Option<&str>) {
     if let Err(e) = fs::create_dir_all(dst).await {
         error!("failed to create dir {dst}: {e}");

src/cmd/init/bootstrap.rs

@@ -180,8 +180,8 @@ async fn mount_system(cfg: &dkl::Config, bs_dir: &str, verifier: &Verifier) {
     for layer in &cfg.layers {
         let src = retry(async || {
             if layer == "modules" {
-                (fs::read("/modules.sqfs").await)
-                    .map_err(|e| format_err!("read /modules.sqfs failed: {e}"))
+                let src = "/modules.sqfs";
+                (fs::read(src).await).map_err(|e| format_err!("read {src} failed: {e}"))
             } else {
                 verifier.verify_path(&format!("{bs_dir}/{layer}.fs")).await
             }