Fixed output when no command line options are specified

src/cliparser.rs

@@ -1,4 +1,4 @@
-use clap::Parser;
+use clap::{CommandFactory, Parser};
 
 #[derive(Debug, Parser)]
 #[command(author, version, about, long_about = None)]
@@ -68,5 +68,14 @@ pub struct CliArgs {
 }
 
 pub fn parse() -> CliArgs {
-    CliArgs::parse()
+    let args = CliArgs::parse();
+
+    if std::env::args().len() == 1 {
+        CliArgs::command()
+            .print_help()
+            .expect("Failed to print help output");
+        std::process::exit(1);
+    }
+
+    args
 }

src/main.rs

@@ -52,7 +52,7 @@ fn main() {
     // Initialize logging
     env_logger::init();
 
-    // Process command line aguments
+    // Process command line arguments
     let mut cliargs = cliparser::parse();
 
     // If --list was specified, just display a list of signatures and return
@@ -66,11 +66,6 @@ fn main() {
         cliargs.file_name = Some(STDIN.to_string());
     }
 
-    // If --list was not specified, a target file must be provided
-    if cliargs.file_name.is_none() {
-        panic!("No target file name specified! Try --help.");
-    }
-
     let mut json_logger = json::JsonLogger::new(cliargs.log);
 
     // If entropy analysis was requested, generate the entropy graph and return