[MPlayer-dev-eng] [PATCH] fix stack usage in libvo/font_load_ft.c

[Ivan Kalvachev]

2006/7/25, Reimar Doeffinger <Reimar.Doeffinger at stud.uni-karlsruhe.de>:
> Hello,
> On Sat, Jul 22, 2006 at 12:01:53AM -0400, Rich Felker wrote:
> > On Fri, Jul 21, 2006 at 08:34:22PM +0000, Tobias Diedrich wrote:
> > > read_font_desc_ft allocates ~1MB on the stack on amd64
> > > (MAX_CHARSET_SIZE is 60000 and sizeof(FT_ULong) is 8).
> >
> > WTF is FT using an unsigned long type for? Someone should tell them
> > they're being stupid and that they should use wchar_t, or just int.
>
> Well, but maybe it is us who are being stupid, because this gigantic
> array seems to be used only in check_font around line 173, which raises
> at least two questions:
> Why are we using FT_ULong and not e.g. int32_t?
> Why are we passing these arrays around (60000 is the maximum size, which
> I guess might be a bit small for some stuff anyway?) instead of e.g. a
> function that provides the mapping?
> Actually for proper unicode support that whole stuff needs to be changed
> not to use the current kind of mapping with a constant-size array.
> 64k characters isn't that much really.

FT_ULong is what freetype uses for characters. It is in their
documentation (FT_Get_Char_Index).

64k is about the number of main unicode (remember when MS though 2
bytes are enough for unicode?)