Adding a HexEncode function to string_utils....

base/string_util.cc

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/string_util.h"
 
 #include "build/build_config.h"
 
 #include <ctype.h>
 #include <errno.h>
@@ skipping 1492 matching lines @@
       int rstr_len = (max_len - 3) / 2;
       int lstr_len = rstr_len + ((max_len - 3) % 2);
       output->assign(input.substr(0, lstr_len) + L"..." +
                      input.substr(input.length() - rstr_len));
       break;
     }
   }
 
   return true;
 }
+
+std::string HexEncode(const void* bytes, size_t size) {
+  static const char kHexChars[] = {

[Dean McNamee, 2009/01/22 11:22:04]

Could you use "0123456789ABCDEF" instead?

+      '0', '1', '2', '3', '4', '5', '6', '7',
+      '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
+
+  if (size == 0)
+    return std::string();
+
+  std::string ret;

[Dean McNamee, 2009/01/22 11:22:04]

Why not:

std::string ret(size * 2, '\0'); or something?

+  // For each byte, we print two characters.
+  ret.resize(size * 2);
+
+  const unsigned char* pos = reinterpret_cast<const unsigned char*>(bytes);
+  const unsigned char* end = pos + size;
+  std::string::iterator write = ret.begin();
+  while (pos < end) {
+    unsigned char b = *pos;
+    pos++;
+
+    write[0] = kHexChars[(b >> 4) & 0xf];

[Dean McNamee, 2009/01/22 11:22:04]

I find write[0] strange if you're treating it like a pointer, why not *write = ?

I personally would have just used an index, and done
write[(i * 2)] = blah
write[(i *  2) + 1] = blah

or something

+    write++;
+
+    write[0] = kHexChars[b & 0xf];
+    write++;
+  }
+
+  return ret;
+}