show ascii too

bin/cli.js

@@ -5,13 +5,19 @@
 var hexdump = require('../').hexdump;
 var fsname = process.argv[2];
 var fs = require('fs');
+var opts = {};
 
-if (!fsname || '--help' === fs || '-h' === fs) {
-  console.error('Usage: hexdump.js <filepath>');
+if (!fsname || '--help' === fsname || '-h' === fsname) {
+  console.error('Usage: hexdump.js -C <filepath>');
   process.exit(2);
   return;
 }
 
+if ('-C' === fsname) {
+  opts.C = true;
+  fsname = process.argv[3];
+}
+
 try {
   fs.statSync(fsname);
 } catch(e) {
@@ -21,7 +27,7 @@ try {
 }
 
 var nb = fs.readFileSync(fsname);
-var str = hexdump(nb.buffer, nb.byteOffset, nb.byteLength);
+var str = hexdump(nb.buffer, nb.byteOffset, nb.byteLength, opts);
 console.log(str);
 
 }());

hexdump.js

@@ -1,7 +1,8 @@
 (function (exports) {
 'use strict';
 
-exports.hexdump = function hexdump(ab, offset, len) {
+exports.hexdump = function hexdump(ab, offset, len, opts) {
+  if (!opts) { opts = {}; }
   var ui8 = new Uint8Array(ab.buffer || ab, offset || ab.byteOffset, len || ab.byteLength);
   var bytecount = 0;
   var head = '        0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F';
@@ -20,7 +21,21 @@ exports.hexdump = function hexdump(ab, offset, len) {
       lead = '0' + lead;
     }
 
+    while (str.length < 48) {
+      str += ' ';
+    }
+
+    if (opts.C) {
+      return lead + ' ' + str + ' |' + str.replace(/ /g, '').match(/.{1,2}/g).map(function (ch) {
+        var c = String.fromCharCode(parseInt(ch, 16));
+        if (!/[ -~]/.test(c)) {
+          c = '.';
+        }
+        return c;
+      }).join('') + '|';
+    } else {
       return lead + ' ' + str;
+    }
   }).join('\n');
 
   trail = (len || ab.byteLength).toString(16);