[Devel] Misfeature in .fon font handling?

[Tor Lillqvist]

There seems to be a problem in the way winfnt.c handles the font (or
face?) name(s). For some fonts, the name doesn't get properly NUL
terminated. See http://bugzilla.gnome.org/show_bug.cgi?id=132366
. There are some false starts earlier in that bug's history (ignore
the HOME and Registry stuff), but see especially Pedro Gimeno's fresh
comment #55, which I quote here:

  Further investigation has led me to the following conclusion: the
  problem is in Freetype. Specifically, the font name happens to be
  the last resource in a frame and the frame size does not include the
  trailing \0.

  In the sample ProFont.fon, at offset 0510h starts the .FON font
  structure about which you can learn e.g. here:
  http://www.csn.ul.ie/~caolan/publink/winresdump/winresdump/doc/resfmt.txt

  Note that the dfSize member in this case equals 0E92h, and exactly
  at offset (0510h+0E92h) = 13A2h there's the trailing \0 which should
  end the string.  However looking at
  freetype-2.1.7/src/winfonts/winfnt.c lines 184 and 502 it seems that
  this trailing \0 is never loaded but the string is used as is. The
  fact that it works properly under Unix somewhat puzzles me.

  I have not investigated the streaming functions of Freetype so I
  can't tell what's a good fix for this problem.

  Of course checking the validity of the font name string can't hurt
  and is even a healthy practice.

--tml