refactor(kernel): construct the path in-place for sysctl sections

systeroid-core/src/docs.rs

@@ -53,9 +53,12 @@ impl SysctlSection {
         ]
     }
 
-    /// Returns the sysctl section as a file with `.rst` extension.
-    pub fn as_file(&self) -> PathBuf {
-        Path::new(&self.to_string()).with_extension("rst")
+    /// Returns the path of the sysctl section.
+    pub fn as_path(&self, kernel_docs: &Path) -> PathBuf {
+        kernel_docs
+            .join("admin-guide")
+            .join("sysctl")
+            .join(Path::new(&self.to_string()).with_extension("rst"))
     }
 }
 

systeroid/src/lib.rs

@@ -7,7 +7,6 @@ pub mod args;
 
 use crate::args::Args;
 use rayon::prelude::*;
-use std::io::{Error as IoError, ErrorKind as IoErrorKind};
 use std::sync::Mutex;
 use systeroid_core::docs::{Documentation, SysctlSection};
 use systeroid_core::error::{Error, Result};
@@ -20,22 +19,13 @@ pub fn run(args: Args) -> Result<()> {
     let mut sysctl = Sysctl::init()?;
 
     let param_docs = if let Some(kernel_docs) = args.kernel_docs {
-        let sysctl_docs = kernel_docs.join("admin-guide").join("sysctl");
-        if !sysctl_docs.exists() {
-            return Err(IoError::new(
-                IoErrorKind::Other,
-                format!("cannot find sysctl documentation: {:?}", sysctl_docs),
-            )
-            .into());
-        }
-
         let param_docs = Mutex::new(Vec::new());
         SysctlSection::variants().par_iter().try_for_each(|s| {
             let mut param_docs = param_docs
                 .lock()
                 .map_err(|e| Error::ThreadLockError(e.to_string()))?;
             let mut parse = |section: SysctlSection| -> Result<()> {
-                let docs = reader::read_to_string(&sysctl_docs.join(section.as_file()))?;
+                let docs = reader::read_to_string(&section.as_path(&kernel_docs))?;
                 param_docs.extend(RstParser::parse_docs(&docs, section)?);
                 Ok(())
             };