Re: Foreign file names on MS-Windows

[Stefan Monnier <monnier@iro.umontreal.ca>]

> --- src/w32.c	24 Feb 2008 10:09:03 -0000	1.130
> +++ src/w32.c	22 Mar 2008 11:51:07 -0000
> @@ -1889,6 +1889,8 @@ closedir (DIR *dirp)
>  struct direct *
>  readdir (DIR *dirp)
>  {
> +  int downcase = !NILP (Vw32_downcase_file_names);
> +
>    if (wnet_enum_handle != INVALID_HANDLE_VALUE)
>      {
>        if (!read_unc_volume (wnet_enum_handle,
> @@ -1923,14 +1925,23 @@ readdir (DIR *dirp)
>       value returned by stat().  */
>    dir_static.d_ino = 1;
 
> +  strcpy (dir_static.d_name, dir_find_data.cFileName);
> +
> +  /* If the file name in cFileName[] includes `?' characters, it means
> +     the original file name used characters that cannot be represented
> +     by the current ANSI codepage.  To avoid total lossage, retrieve
> +     the short 8+3 alias of the long file name.  */
> +  if (_mbspbrk (dir_static.d_name, "?"))
> +    {
> +      strcpy (dir_static.d_name, dir_find_data.cAlternateFileName);
> +      downcase = 1;	/* 8+3 aliases are returned in all caps */
> +    }
> +  dir_static.d_namlen = strlen (dir_static.d_name);
>    dir_static.d_reclen = sizeof (struct direct) - MAXNAMLEN + 3 +
>      dir_static.d_namlen - dir_static.d_namlen % 4;
> -
> -  dir_static.d_namlen = strlen (dir_find_data.cFileName);
> -  strcpy (dir_static.d_name, dir_find_data.cFileName);
>    if (dir_is_fat)
>      _strlwr (dir_static.d_name);
> -  else if (!NILP (Vw32_downcase_file_names))
> +  else if (downcase)
>      {
>        register char *p;
>        for (p = dir_static.d_name; *p; p++)

Why not just as in the patch below?
I.e. why fiddle with Vw32_downcase_file_names?
And more importantly why modify the code to change dir_static.d_namlen
before the computation of dir_static.d_reclen (which uses
dir_static.d_namlen)?

The patch below would seem pretty safe to me, whereas yours isn't quite
as obvious.  Yet, it looks like there was a good reason to do it the way
you did.


        Stefan


--- w32.c.~1.130.~	2008-02-24 08:11:40.000000000 -0500
+++ w32.c	2008-03-22 13:31:01.000000000 -0400
@@ -1926,8 +1926,16 @@
   dir_static.d_reclen = sizeof (struct direct) - MAXNAMLEN + 3 +
     dir_static.d_namlen - dir_static.d_namlen % 4;
 
-  dir_static.d_namlen = strlen (dir_find_data.cFileName);
+  /* If the file name in cFileName[] includes `?' characters, it means
+     the original file name used characters that cannot be represented
+     by the current ANSI codepage.  To avoid total lossage, retrieve
+     the short 8+3 alias of the long file name.  */
+  if (_mbspbrk (dir_find_data.cFileName, "?"))
+    strcpy (dir_static.d_name, dir_find_data.cAlternateFileName);
+  else
   strcpy (dir_static.d_name, dir_find_data.cFileName);
+  dir_static.d_namlen = strlen (dir_static.d_name);
+
   if (dir_is_fat)
     _strlwr (dir_static.d_name);
   else if (!NILP (Vw32_downcase_file_names))