Function blkid_probe

crates/blockdev/src/blockdev.rs:47–71

Probe a device with `blkid -p` and return all discovered properties as key-value pairs. This uses the `export` output format (`KEY=value`, one per line) to retrieve all tags in a single invocation, rather than spawning blkid once per property. Returns `Ok(empty map)` if blkid exits with code 2 (no tags found, e.g. the device is a whole disk). Other non-zero exits are propagated as errors.

(dev: &str)

/// e.g. the device is a whole disk). Other non-zero exits are propagated
/// as errors.
fn blkid_probe(dev: &str) -> Result<HashMap<String, String>> {
    let mut cmd = Command::new("blkid");
    cmd.args(["-p", "-o", "export"]).arg(dev);
    cmd.log_debug();
    let output = cmd.output().context("Failed to run blkid")?;
    if !output.status.success() {
        // blkid exits with 2 when no tags are found (e.g. whole disk)
        if output.status.code() == Some(2) {
            return Ok(HashMap::new());
        }
        let stderr = String::from_utf8_lossy(&output.stderr);
        anyhow::bail!(
            "blkid -p failed on {dev} (exit status {}): {stderr}",
            output.status
        );
    }
    let text = String::from_utf8(output.stdout).context("blkid output is not UTF-8")?;
    let mut props = HashMap::new();
    for line in text.lines() {
        if let Some((key, value)) = line.split_once('=') {
            props.insert(key.to_string(), value.to_string());
        }
    }
    Ok(props)
}

/// MBR partition type IDs that indicate an EFI System Partition.
/// 0x06 is FAT16 (used as ESP on some MBR systems), 0xEF is the