/* Unix/HPFS filename translation for FAT file systems */

/* Author: Kai Uwe Rommel */

#include <stddef.h>
#include <string.h>
#include <ctype.h>


void ChangeNameForFAT(char *name)
{
  char *src, *dst, *next, *ptr, *dot;

  if ( isalpha(name[0]) && (name[1] == ':') )
    src = dst = name + 2;
  else
    src = dst = name;

  if ( (*src == '/') || (*src == '\\') )
    src++, dst++;

  while ( *src )
  {
    for ( next = src; *next && (*next != '/') && (*next != '\\'); next++ );

    for ( ptr = src, dot = NULL; ptr < next; ptr++ )
      if ( *ptr == '.' )
        *(dot = ptr) = '_'; /* remember last dot */

    if ( dot && (dot > src) &&
         ((next - dot <= 4) ||
          ((next - src > 8) && (dot - src > 3))) )
    {
      *dot = '.';

      for ( ptr = src; (ptr < dot) && ((ptr - src) < 8); ptr++ )
        *dst++ = *ptr;

      for ( ptr = dot; (ptr < next) && ((ptr - dot) < 4); ptr++ )
        *dst++ = *ptr;
    }
    else
      for ( ptr = src; (ptr < next) && ((ptr - src) < 8); ptr++ )
        *dst++ = *ptr;

    *dst++ = *next; /* either '/' or 0 */

    if ( *next )
    {
      src = next + 1;

      if ( *src == 0 ) /* handle trailing '/' on dirs ! */
        *dst = 0;
    }
    else
      break;
  }
}