Ah sorry, I posted it through the Google Groups mirror and I think it
may have eaten my original message. Here it is again:
SysFont hangs when loading certain fonts. For example, on my Windows 7
machine, I can produce a hang with the line
pygame.font.SysFont("vivaldi", 12)
(See the attached script, sysfont_hang.py, which should reproduce it
on any machine.)
The problem is that SysFont assumes that every system font has a
non-bold, non-italic version, and this assumption causes it to enter
an infinite loop. In the example above, the font "vivaldi" in fact
only has one version, an italic, non-bold version. This messes with
the following code from lib/sysfont.py:
-------------------
def SysFont(name, size, bold=False, italic=False, constructor=None):
if constructor is None:
constructor = font_constructor
if not Sysfonts:
initsysfonts()
gotbold = gotitalic = False
fontname = None
if name:
allnames = name
for name in allnames.split(','):
name = _simplename(name)
styles = Sysfonts.get(name)
if not styles:
styles = Sysalias.get(name)
if styles:
while not fontname:
plainname = styles.get((False, False))
fontname = styles.get((bold, italic))
if not fontname:
fontname = plainname
elif plainname != fontname:
gotbold = bold
gotitalic = italic
if fontname: break
set_bold = set_italic = False
if bold and not gotbold:
set_bold = True
if italic and not gotitalic:
set_italic = True
return constructor(fontname, size, set_bold, set_italic)
-------------------
This while loop is the part that hangs:
-------------------
if styles:
while not fontname:
plainname = styles.get((False, False))
fontname = styles.get((bold, italic))
if not fontname:
fontname = plainname
elif plainname != fontname:
gotbold = bold
gotitalic = italic
-------------------
The problem is that "styles", in the case of a font like "vivaldi" on
Windows 7, is this map:
{(0, 1): "PATH_TO_FONT"}
With a bit of examination, it can be seen that in such a case, this
while loop will never terminate.
I haven't attached a patch because I'm not sure exactly the right way
to fix this. Should it simply return list(styles.values())[0] in this
case, should it throw an exception, or should it default to pygame's
default font?
Thanks for reading,
Jeremy Sharpe
On Wed, Aug 17, 2011 at 5:18 PM, René Dudfield <renesd@xxxxxxxxx> wrote:
> On Wed, Aug 17, 2011 at 11:10 PM, Jeremy Sharpe
> <jeremy.adamson.sharpe@xxxxxxxxx> wrote:
>>
>> I see that rev 964 fixed a similar bug in this area of code, but seems to
>> have missed the case where both fontname AND plainname are None, which is
>> what results in the infinite loop.
>
> Hello,
>
> I think I may have missed an earlier email... What should be changed to fix
> it?
>
Attachment:
sysfont_hang.py
Description: Binary data