parser/bls: New file

Signed-off-by: Johan-Liebert1 <[email protected]>
Signed-off-by: Colin Walters <[email protected]>

Author: Johan-Liebert1

crates/lib/src/parsers/bls_config.rs

@@ -0,0 +1,205 @@
+//! See <https://uapi-group.org/specifications/specs/boot_loader_specification/>
+//!
+//! This module parses the config files for the spec.
+
+use anyhow::Result;
+use serde::de::Error;
+use serde::{Deserialize, Deserializer};
+use std::collections::HashMap;
+use std::fmt::Display;
+
+#[derive(Debug, Deserialize, Eq)]
+pub(crate) struct BLSConfig {
+    pub(crate) title: Option<String>,
+    #[serde(deserialize_with = "deserialize_version")]
+    pub(crate) version: u32,
+    pub(crate) linux: String,
+    pub(crate) initrd: String,
+    pub(crate) options: String,
+
+    #[serde(flatten)]
+    pub(crate) extra: HashMap<String, String>,
+}
+
+impl PartialEq for BLSConfig {
+    fn eq(&self, other: &Self) -> bool {
+        self.version == other.version
+    }
+}
+
+impl PartialOrd for BLSConfig {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        self.version.partial_cmp(&other.version)
+    }
+}
+
+impl Ord for BLSConfig {
+    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+        self.version.cmp(&other.version)
+    }
+}
+
+impl Display for BLSConfig {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        if let Some(title) = &self.title {
+            writeln!(f, "title {}", title)?;
+        }
+
+        writeln!(f, "version {}", self.version)?;
+        writeln!(f, "linux {}", self.linux)?;
+        writeln!(f, "initrd {}", self.initrd)?;
+        writeln!(f, "options {}", self.options)?;
+
+        for (key, value) in &self.extra {
+            writeln!(f, "{} {}", key, value)?;
+        }
+
+        Ok(())
+    }
+}
+
+fn deserialize_version<'de, D>(deserializer: D) -> Result<u32, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    let s: Option<String> = Option::deserialize(deserializer)?;
+
+    match s {
+        Some(s) => Ok(s.parse::<u32>().map_err(D::Error::custom)?),
+        None => Err(D::Error::custom("Version not found")),
+    }
+}
+
+pub(crate) fn parse_bls_config(input: &str) -> Result<BLSConfig> {
+    let mut map = HashMap::new();
+
+    for line in input.lines() {
+        let line = line.trim();
+        if line.is_empty() || line.starts_with('#') {
+            continue;
+        }
+
+        if let Some((key, value)) = line.split_once(' ') {
+            map.insert(key.to_string(), value.trim().to_string());
+        }
+    }
+
+    let value = serde_json::to_value(map)?;
+    let parsed: BLSConfig = serde_json::from_value(value)?;
+
+    Ok(parsed)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_parse_valid_bls_config() -> Result<()> {
+        let input = r#"
+            title Fedora 42.20250623.3.1 (CoreOS)
+            version 2
+            linux /boot/7e11ac46e3e022053e7226a20104ac656bf72d1a84e3a398b7cce70e9df188b6/vmlinuz-5.14.10
+            initrd /boot/7e11ac46e3e022053e7226a20104ac656bf72d1a84e3a398b7cce70e9df188b6/initramfs-5.14.10.img
+            options root=UUID=abc123 rw composefs=7e11ac46e3e022053e7226a20104ac656bf72d1a84e3a398b7cce70e9df188b6
+            custom1 value1
+            custom2 value2
+        "#;
+
+        let config = parse_bls_config(input)?;
+
+        assert_eq!(
+            config.title,
+            Some("Fedora 42.20250623.3.1 (CoreOS)".to_string())
+        );
+        assert_eq!(config.version, 2);
+        assert_eq!(config.linux, "/boot/7e11ac46e3e022053e7226a20104ac656bf72d1a84e3a398b7cce70e9df188b6/vmlinuz-5.14.10");
+        assert_eq!(config.initrd, "/boot/7e11ac46e3e022053e7226a20104ac656bf72d1a84e3a398b7cce70e9df188b6/initramfs-5.14.10.img");
+        assert_eq!(config.options, "root=UUID=abc123 rw composefs=7e11ac46e3e022053e7226a20104ac656bf72d1a84e3a398b7cce70e9df188b6");
+        assert_eq!(config.extra.get("custom1"), Some(&"value1".to_string()));
+        assert_eq!(config.extra.get("custom2"), Some(&"value2".to_string()));
+
+        Ok(())
+    }
+
+    #[test]
+    fn test_parse_missing_version() {
+        let input = r#"
+            title Fedora
+            linux /vmlinuz
+            initrd /initramfs.img
+            options root=UUID=xyz ro quiet
+        "#;
+
+        let parsed = parse_bls_config(input);
+        assert!(parsed.is_err());
+    }
+
+    #[test]
+    fn test_parse_invalid_version_format() {
+        let input = r#"
+            title Fedora
+            version not_an_int
+            linux /vmlinuz
+            initrd /initramfs.img
+            options root=UUID=abc composefs=some-uuid
+        "#;
+
+        let parsed = parse_bls_config(input);
+        assert!(parsed.is_err());
+    }
+
+    #[test]
+    fn test_display_output() -> Result<()> {
+        let input = r#"
+            title Test OS
+            version 10
+            linux /boot/vmlinuz
+            initrd /boot/initrd.img
+            options root=UUID=abc composefs=some-uuid
+            foo bar
+        "#;
+
+        let config = parse_bls_config(input)?;
+        let output = format!("{}", config);
+        let mut output_lines = output.lines();
+
+        assert_eq!(output_lines.next().unwrap(), "title Test OS");
+        assert_eq!(output_lines.next().unwrap(), "version 10");
+        assert_eq!(output_lines.next().unwrap(), "linux /boot/vmlinuz");
+        assert_eq!(output_lines.next().unwrap(), "initrd /boot/initrd.img");
+        assert_eq!(
+            output_lines.next().unwrap(),
+            "options root=UUID=abc composefs=some-uuid"
+        );
+        assert_eq!(output_lines.next().unwrap(), "foo bar");
+
+        Ok(())
+    }
+
+    #[test]
+    fn test_ordering() -> Result<()> {
+        let config1 = parse_bls_config(
+            r#"
+            title Entry 1
+            version 3
+            linux /vmlinuz-3
+            initrd /initrd-3
+            options opt1
+        "#,
+        )?;
+
+        let config2 = parse_bls_config(
+            r#"
+            title Entry 2
+            version 5
+            linux /vmlinuz-5
+            initrd /initrd-5
+            options opt2
+        "#,
+        )?;
+
+        assert!(config1 < config2);
+        Ok(())
+    }
+}

crates/lib/src/parsers/mod.rs

@@ -1 +1,2 @@
+pub(crate) mod bls_config;
 pub(crate) mod grub_menuconfig;