print once when unknown algo

src/main.rs

@@ -49,7 +49,7 @@ fn main() -> XResult<()> {
     let options = Options::new_and_parse_args()?;
 
     if options.version {
-        print_version();
+        print_version(&options);
         return Ok(());
     }
 
@@ -87,7 +87,7 @@ fn main() -> XResult<()> {
     Ok(())
 }
 
-fn print_version() {
+fn print_version(options: &Options) {
     print!(r#"digest {} - {}
 Copyright (C) 2019 Hatter Jiang.
 License MIT <https://opensource.org/licenses/MIT>
@@ -100,6 +100,9 @@ SHA3-224, SHA3-256, SHA3-384, SHA3-512, SHAKE-128, SHAKE-256,
 KECCAK-224, KECCAK-256, KECCAK-384, KECCAK-512,
 SM3, RIPEMD160, WHIRLPOOL, BLAKE2S, BLAKE2B
 "#, VERSION, &GIT_HASH[0..7]);
+    if options.verbose {
+        print_message(MessageType::DEBUG, &format!("Full git hash: {}", &GIT_HASH));
+    }
 }
 
 fn get_digest_by_algorithm(algo: &str, options: &Options) -> Option<Box<dyn Digest>> {

src/opt.rs

@@ -3,6 +3,7 @@ use argparse::{ArgumentParser, StoreTrue, Store, List};
 
 pub struct Options {
     pub version: bool,
+    pub verbose: bool,
     pub algorithm: String,
     pub file_name_list: Vec<String>,
     pub blake_len: usize,
@@ -12,6 +13,7 @@ impl Options {
     pub fn new() -> Options {
         Options {
             version: false,
+            verbose: false,
             algorithm: "SHA256".to_string(),
             file_name_list: Vec::new(),
             blake_len: 0_usize,
@@ -24,7 +26,8 @@ impl Options {
             ap.set_description("digest - command line digest tool.");
             ap.refer(&mut self.algorithm).add_option(&["-a", "--algorithm"], Store, "Algorithm, e.g. SHA256, SM3");
             ap.refer(&mut self.blake_len).add_option(&["-l", "--blake-len"], Store, "Blake2s/b length, 1~32/64");
-            ap.refer(&mut self.version).add_option(&["-v", "--version"], StoreTrue, "Print version");
+            ap.refer(&mut self.version).add_option(&["-V", "--version"], StoreTrue, "Print version");
+            ap.refer(&mut self.verbose).add_option(&["-v", "--verbose"], StoreTrue, "Verbose");
             ap.refer(&mut self.file_name_list).add_argument("File names", List, "File names to be digested");
             ap.parse_args_or_exit();
         }