[cairo] Implementing cairo_read_func_t/cairo_write_func_t properly

[Bernhard Fischer]

On Friday 01 January 2016 22:42:30 Lawrence D'Oliveiro wrote:
> On Fri, 01 Jan 2016 10:32:59 +0100, Bernhard Fischer wrote:
> > cairo_..._stream() are stream reading functions. This is that it does
> > not know in advance how many bytes are available in the file.
> 
> That’s not how they work. Cairo uses them to read known file formats.
> If it doesn’t get the number of bytes it expects, then there is
> something wrong with the file.


Of course, but still you can't know in advance how many bytes to expect, even 
if the format is known (e.g. not all formats have length fields).

Bernhard