feat(args): add --verbose flag for logging verbosity

systeroid-core/src/config.rs

@@ -60,6 +60,8 @@ impl Default for AppConfig {
 /// Sysctl configuration.
 #[derive(Debug, Default)]
 pub struct SysctlConfig {
+    /// Whether if the verbose logging is enabled.
+    pub verbose: bool,
     /// Whether if the errors should be ignored.
     pub ignore_errors: bool,
 }

systeroid-core/src/sysctl/controller.rs

@@ -32,7 +32,9 @@ impl Sysctl {
                     parameters.push(parameter);
                 }
                 Err(e) => {
-                    eprintln!("error: `{} ({})`", e, ctl.name()?);
+                    if config.verbose {
+                        eprintln!("{} ({})", e, ctl.name()?);
+                    }
                 }
             }
         }

systeroid/src/args.rs

@@ -17,6 +17,8 @@ For more details see {bin}(8)."#;
 /// Command-line arguments.
 #[derive(Debug, Default)]
 pub struct Args {
+    /// Whether if the verbose logging is enabled.
+    pub verbose: bool,
     /// Path of the Linux kernel documentation.
     pub kernel_docs: Option<PathBuf>,
     /// Display type of the variables.
@@ -62,7 +64,8 @@ impl Args {
             "set the path of the kernel documentation",
             "<path>",
         );
-        opts.optflag("P", "no-pager", "Do not pipe output into a pager");
+        opts.optflag("P", "no-pager", "do not pipe output into a pager");
+        opts.optflag("v", "verbose", "enable the verbose logging");
         opts.optflag("h", "help", "display this help and exit");
         opts.optflag("V", "version", "output version information and exit");
 
@@ -108,6 +111,7 @@ impl Args {
                 DisplayType::Default
             };
             Some(Args {
+                verbose: matches.opt_present("v"),
                 kernel_docs: matches.opt_str("d").map(PathBuf::from),
                 display_type,
                 ignore_errors: matches.opt_present("e"),

systeroid/src/lib.rs

@@ -17,6 +17,7 @@ use systeroid_core::sysctl::controller::Sysctl;
 /// Runs `systeroid`.
 pub fn run(args: Args) -> Result<()> {
     let mut config = Config::default();
+    config.sysctl.verbose = args.verbose;
     config.sysctl.ignore_errors = args.ignore_errors;
     config.app.display_type = args.display_type;
     config.app.no_color = env::var("NO_COLOR").is_ok();