tolf and detab

[Walter Bright]

I wrote these two trivial utilities for the purpose of canonicalizing source 
code before checkins and to deal with FreeBSD's inability to deal with CRLF line 
endings, and because I can never figure out the right settings for git to make 
it do the canonicalization.

tolf - converts LF, CR, and CRLF line endings to LF.

detab - converts all tabs to the correct number of spaces. Assumes tabs are 8 
column tabs. Removes trailing whitespace from lines.

Posted here just in case someone wonders what they are.
---------------------------------------------------------
/* Replace tabs with spaces, and remove trailing whitespace from lines.
  */

import std.file;
import std.path;

int main(string[] args)
{
     foreach (f; args[1 .. $])
     {
         auto input = cast(char[]) std.file.read(f);
         auto output = filter(input);
         if (output != input)
             std.file.write(f, output);
     }
     return 0;
}


char[] filter(char[] input)
{
     char[] output;
     size_t j;

     int column;
     for (size_t i = 0; i < input.length; i++)
     {
         auto c = input[i];

         switch (c)
         {
             case '\t':
                 while ((column & 7) != 7)
                 {   output ~= ' ';
                     j++;
                     column++;
                 }
                 c = ' ';
                 column++;
                 break;

             case '\r':
             case '\n':
                 while (j && output[j - 1] == ' ')
                     j--;
                 output = output[0 .. j];
                 column = 0;
                 break;

             default:
                 column++;
                 break;
         }
         output ~= c;
         j++;
     }
     while (j && output[j - 1] == ' ')
         j--;
     return output[0 .. j];
}
-----------------------------------------------------
/* Replace line endings with LF
  */

import std.file;
import std.path;

int main(string[] args)
{
     foreach (f; args[1 .. $])
     {
         auto input = cast(char[]) std.file.read(f);
         auto output = filter(input);
         if (output != input)
             std.file.write(f, output);
     }
     return 0;
}


char[] filter(char[] input)
{
     char[] output;
     size_t j;

     for (size_t i = 0; i < input.length; i++)
     {
         auto c = input[i];

         switch (c)
         {
             case '\r':
                 c = '\n';
                 break;

             case '\n':
                 if (i && input[i - 1] == '\r')
                     continue;
                 break;

             case 0:
                 continue;

             default:
                 break;
         }
         output ~= c;
         j++;
     }
     return output[0 .. j];
}
------------------------------------------