chore(code): move crates/sprout to crates/boot and name it edera-sprout-boot

crates/boot/src/generators/bls/entry.rs

@@ -0,0 +1,168 @@
+use alloc::string::{String, ToString};
+use anyhow::{Error, Result};
+use core::str::FromStr;
+
+/// Represents a parsed BLS entry.
+/// Fields unrelated to Sprout are not included.
+#[derive(Default, Debug, Clone)]
+pub struct BlsEntry {
+    /// The title of the entry.
+    pub title: Option<String>,
+    /// The options to pass to the entry.
+    pub options: Option<String>,
+    /// The path to the linux kernel.
+    pub linux: Option<String>,
+    /// The path to the initrd.
+    pub initrd: Option<String>,
+    /// The path to an EFI image.
+    pub efi: Option<String>,
+    /// The sort key for the entry.
+    pub sort_key: Option<String>,
+    /// The version of the entry.
+    pub version: Option<String>,
+    /// The machine id of the entry.
+    pub machine_id: Option<String>,
+}
+
+/// Parser for a BLS entry.
+impl FromStr for BlsEntry {
+    type Err = Error;
+
+    /// Parses the `input` as a BLS entry file.
+    fn from_str(input: &str) -> Result<Self> {
+        // All the fields in a BLS entry we understand.
+        // Set all to None initially.
+        let mut title: Option<String> = None;
+        let mut options: Option<String> = None;
+        let mut linux: Option<String> = None;
+        let mut initrd: Option<String> = None;
+        let mut efi: Option<String> = None;
+        let mut sort_key: Option<String> = None;
+        let mut version: Option<String> = None;
+        let mut machine_id: Option<String> = None;
+
+        // Iterate over each line in the input and parse it.
+        for line in input.lines() {
+            // Trim the line.
+            let line = line.trim();
+
+            // Skip over empty lines and comments.
+            if line.is_empty() || line.starts_with('#') {
+                continue;
+            }
+
+            // Split the line once by whitespace. This technically includes newlines but since
+            // the lines iterator is used, there should never be a newline here.
+            let Some((key, value)) = line.split_once(char::is_whitespace) else {
+                continue;
+            };
+
+            // Match the key to a field we understand.
+            match key {
+                // The title of the entry.
+                "title" => {
+                    title = Some(value.trim().to_string());
+                }
+
+                // The options to pass to the entry.
+                "options" => {
+                    options = Some(value.trim().to_string());
+                }
+
+                // The path to the linux kernel.
+                "linux" => {
+                    linux = Some(value.trim().to_string());
+                }
+
+                // The path to the initrd.
+                "initrd" => {
+                    initrd = Some(value.trim().to_string());
+                }
+
+                // The path to an EFI image.
+                "efi" => {
+                    efi = Some(value.trim().to_string());
+                }
+
+                "sort-key" => {
+                    sort_key = Some(value.trim().to_string());
+                }
+
+                "version" => {
+                    version = Some(value.trim().to_string());
+                }
+
+                "machine-id" => {
+                    machine_id = Some(value.trim().to_string());
+                }
+
+                // Ignore any other key.
+                _ => {
+                    continue;
+                }
+            }
+        }
+
+        // Produce a BLS entry from the parsed fields.
+        Ok(Self {
+            title,
+            options,
+            linux,
+            initrd,
+            efi,
+            sort_key,
+            version,
+            machine_id,
+        })
+    }
+}
+
+impl BlsEntry {
+    /// Checks if this BLS entry is something we can actually boot in Sprout.
+    pub fn is_valid(&self) -> bool {
+        self.linux.is_some() || self.efi.is_some()
+    }
+
+    /// Fetches the path to an EFI bootable image to boot, if any.
+    /// This prioritizes the linux field over efi.
+    /// It also converts / to \\ to match EFI path style.
+    pub fn chainload_path(&self) -> Option<String> {
+        self.linux
+            .clone()
+            .or(self.efi.clone())
+            .map(|path| path.replace('/', "\\").trim_start_matches('\\').to_string())
+    }
+
+    /// Fetches the path to an initrd to pass to the kernel, if any.
+    /// It also converts / to \\ to match EFI path style.
+    pub fn initrd_path(&self) -> Option<String> {
+        self.initrd
+            .clone()
+            .map(|path| path.replace('/', "\\").trim_start_matches('\\').to_string())
+    }
+
+    /// Fetches the options to pass to the kernel, if any.
+    pub fn options(&self) -> Option<String> {
+        self.options.clone()
+    }
+
+    /// Fetches the title of the entry, if any.
+    pub fn title(&self) -> Option<String> {
+        self.title.clone()
+    }
+
+    /// Fetches the sort key of the entry, if any.
+    pub fn sort_key(&self) -> Option<String> {
+        self.sort_key.clone()
+    }
+
+    /// Fetches the version of the entry, if any.
+    pub fn version(&self) -> Option<String> {
+        self.version.clone()
+    }
+
+    /// Fetches the machine id of the entry, if any.
+    pub fn machine_id(&self) -> Option<String> {
+        self.machine_id.clone()
+    }
+}