Re: [pygame] Segfault on loading font from StringIO

[Radomir Dopieralski <pygame@xxxxxxxxxxxx>]

I think that this comment is related to this problem:
http://archives.seul.org/pygame/users/Jan-2004/msg00035.html

On Mon, Jan 2, 2012 at 13:46, Russell Jones <russell.jones@xxxxxxxxx> wrote:
> In summary, the font reading function in SDL relies on a filename, so as it
> stands, reading from a file-like object won't work. Covering the buffer to a
> string causes the data to be interpreted as a filename, which unsurprisingly
> gives an IOError saying the font filename can't be read (line 600 of
> font.c).
>
> I had a look on Debian testing in a VM, and it seems to be happening in
> SDL_RWFromFile, which is not in font.c, but is called by its functions. I
> couldn't see where the error was happening in font.c as there are no pygame
> debug symbols available. I'm guessing it's the line
> rw = RWopsFromPython (fileobj)
> (RWopsFromPython is from rwobject.c and calls get_standard_rwop, which calls
> either SDL_RWFromFile or SDL_RWFromFP if it can't extract a name from
> fileobj)
>
> It seems likely to be related to this comment in font_init() : /*check if it
> is a valid file, else SDL_ttf segfaults*/. I guess SDL_RWFromMem could be
> used with some kind of translation from the buffer, or SDL_RWFromFile could
> be altered to accept a file object. The SDL API spec for FromFile relies on
> a filename, however, and FromFile does the opening of the file itself using
> that.
>
> Russell
>
> On 1 January 2012 10:50, Radomir Dopieralski <pygame@xxxxxxxxxxxx> wrote:
>>
>> Hello everyone,
>>
>> I'm having a problem loading a font file from a python file-like
>> object. According to the documentation at
>> http://www.pygame.org/docs/ref/font.html#pygame.font.Font this should
>> be possible, however, I get a segmentation fault every time I pass a
>> file-like object that is not created by opening a real file. I want to
>> load all my assets from a zip archive, so it's not possible to have a
>> real file in the filesystem.
>>
>> A simple test case:
>>
>> import pygame
>> import StringIO
>>
>> pygame.font.init()
>>
>> f = open("somefont.ttf", "r")
>> font = pygame.font.Font(f, 8) # Works fine
>> f.close()
>>
>> f = open("somefont.ttf", "r")
>> buffer = StringIO.StringIO(f.read())
>> f.close()
>> font = pygame.font.Font(buffer, 8) # Segfault
>>
>> Is there any way to make it work as documented? If the documentation
>> is wrong, is there any way to create a pygame font object without
>> creating a real file in the filesystem?
>>
>> Thanks,
>> --
>> Radomir Dopieralski
>
>