Extract get_var_if_exists into common code

And use it for MUVM_UDEVD_PATH

Signed-off-by: Val Packett <[email protected]>

Author: valpackett

crates/muvm/src/config.rs

@@ -1,25 +1,18 @@
 use std::{
-    env::{self, VarError},
-    io,
+    env, io,
     path::{Path, PathBuf},
 };
 
 use anyhow::{Context, Result};
 use serde::{Deserialize, Serialize};
 
+use crate::utils::env::get_var_if_exists;
+
 #[derive(Deserialize, Serialize, Default)]
 pub struct Configuration {
     pub execute_pre: Option<PathBuf>,
 }
 
-fn get_var_if_exists(name: &str) -> Option<Result<String>> {
-    match env::var(name) {
-        Ok(val) => Some(Ok(val)),
-        Err(VarError::NotPresent) => None,
-        Err(e) => Some(Err(e.into())),
-    }
-}
-
 fn get_user_config_path() -> Result<PathBuf> {
     let mut path = get_var_if_exists("XDG_CONFIG_DIR").map_or_else(
         || {

crates/muvm/src/guest/bin/muvm-guest.rs

@@ -17,6 +17,7 @@ use muvm::guest::server::server_main;
 use muvm::guest::socket::setup_socket_proxy;
 use muvm::guest::user::setup_user;
 use muvm::guest::x11::setup_x11_forwarding;
+use muvm::utils::env::get_var_if_exists;
 use muvm::utils::launch::{Emulator, GuestConfiguration, PULSE_SOCKET};
 use nix::unistd::{Gid, Uid};
 use rustix::process::{getrlimit, setrlimit, Resource};
@@ -82,7 +83,8 @@ fn main() -> Result<ExitCode> {
         None => "/usr/lib/systemd/systemd-udevd",
     };
     Command::new(
-        env::var("MUVM_UDEVD_PATH").unwrap_or_else(|_| DEFAULT_UDEVD_PATH.parse().unwrap()),
+        get_var_if_exists("MUVM_UDEVD_PATH")
+            .unwrap_or_else(|| Ok(DEFAULT_UDEVD_PATH.to_owned()))?,
     )
     .spawn()
     .context("Failed to execute `systemd-udevd` as a child process")?;

crates/muvm/src/utils/env.rs

@@ -32,3 +32,11 @@ where
 
     Ok(None)
 }
+
+pub fn get_var_if_exists(name: &str) -> Option<Result<String>> {
+    match env::var(name) {
+        Ok(val) => Some(Ok(val)),
+        Err(env::VarError::NotPresent) => None,
+        Err(e) => Some(Err(e.into())),
+    }
+}