[pdf-devel] Stream buffer flaw

[gerel]

Hey everyone,

There is a flaw in the full_p function that allows a filter to overflows the
buffer->data pointer. Basically it's not working,

I use printf() in the RL filter to show the behavior.
##
size: 1, wp: 0, rp: 0,  and It is NOT full
size: 1, wp: 0, rp: 0,  and It is NOT full
size: 1, wp: 0, rp: 0,  and It is NOT full
size: 1, wp: 1, rp: 1,  and It is NOT full
size: 1, wp: 1, rp: 1,  and It is NOT full
###

The last two should say "It is full".

You can check the above prints are consistent (yet undesired) with the code,
see:
##
pdf_bool_t
pdf_stm_buffer_full_p (pdf_stm_buffer_t buffer)
{
  return ((buffer->wp == buffer->size) &&
          (buffer->rp != buffer->wp));
}
###

I don't know what kind of buffer we're trying to implement.
jemarch, what kind of buffer is that you have in mind ? Let's put it clear. :-)


cheers

-gerel