[Devel] Bug in ftbdf.c?

[Joe Marcus Clarke]

After Keith Packard's latest diffs to fontconfig, I think I found a bug
in ftbdf.c.  When a font face created from a font such as the Windows
VGAFIX.FON is passed to FT_Get_BDF_Property(), 
driver->root.clazz->get_interface is called unchecked.  It so happens
that with fonts such as this, get_interface is 0.  The attached patch to
ftbdf.c corrects the problem, but I'm not sure if this is the correct
place for the patch.  Perhaps there is something fontconfig is doing
wrong, but I can't see what it is.  Here is a stack trace of the
problem:

#0  0x0 in ?? ()
#1  0x2809a771 in FT_Get_BDF_Property (face=0x804f100,
    prop_name=0x2808179e "FOUNDRY", aproperty=0xbfbff650)
    at
/usr/ports/print/freetype2/work/freetype-2.1.4/src/base/ftbdf.c:90
#2  0x2807724d in FcFreeTypeQuery (
    file=0x8050000 "/usr/X11R6/lib/X11/fonts/xxx/VGAFIX.FON", id=0,
    blanks=0x8058680, count=0xbfbff6dc) at fcfreetype.c:784
#3  0x2807626a in FcFileScan (set=0x804d0a0, dirs=0x804d0e0, cache=0x0,
    blanks=0x8058680,
    file=0x8050000 "/usr/X11R6/lib/X11/fonts/xxx/VGAFIX.FON", force=1)
    at fcdir.c:113
#4  0x280764eb in FcDirScan (set=0x804d0a0, dirs=0x804d0e0, cache=0x0,
    blanks=0x8058680, dir=0x804b020 "/usr/X11R6/lib/X11/fonts/xxx",
force=1)
    at fcdir.c:221
#5  0x8048d55 in scanDirs (list=0x804d090, config=0x804c000,
    program=0xbfbff9b4 "fc-cache", force=1, verbose=1) at fc-cache.c:166
#6  0x8049008 in main (argc=4, argv=0xbfbff880) at fc-cache.c:278
#7  0x8048a22 in _start ()
(gdb) frame 1
(gdb) print *driver->root.clazz
$1 = {module_flags = 1, module_size = 40, module_name = 0x280d8196
"winfonts",
  module_version = 65536, module_requires = 131072, module_interface =
0x0,
  module_init = 0, module_done = 0, get_interface = 0}

Joe

-- 
Joe Marcus Clarke
FreeBSD GNOME Team      ::      address@hidden
http://www.FreeBSD.org/gnome

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