add BLAKE2S, BLAKE2B

src/opt.rs

@@ -5,6 +5,7 @@ pub struct Options {
     pub version: bool,
     pub algorithm: String,
     pub file_name_list: Vec<String>,
+    pub blake_len: usize,
 }
 
 impl Options {
@@ -13,6 +14,7 @@ impl Options {
             version: false,
             algorithm: "SHA256".to_string(),
             file_name_list: Vec::new(),
+            blake_len: 0_usize,
         }
     }
 
@@ -21,6 +23,7 @@ impl Options {
             let mut ap = ArgumentParser::new();
             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.file_name_list).add_argument("File names", List, "File names to be digested");
             ap.parse_args_or_exit();