[comp.os.minix] Atari screen driver

7103_300@uwovax.uwo.ca (Eric Smith) (02/10/89)

Here's a patch to my recently posted screen driver for the Atari ST.
It corrects a bug in which invalid parameters to the ioctl call
weren't caught. Of course, my programs never contain invalid parameters,
so I never noticed this problem :->.
--
Eric R. Smith                     email:
Dept. of Mathematics            7103_300@uwovax.uwo.ca
University of Western Ontario   7103_300@uwovax.bitnet
London, Ont. Canada N6A 5B7     (a shared mailbox: put my name on
ph: (519) 661-3638              the message, please!)
----------- cut here --------
*** /tmp/,RCSt1000088	Thu Feb  9 17:50:18 1989
--- memory.c	Thu Feb  9 17:47:09 1989
***************
*** 230,235 ****
--- 230,237 ----
  		return EINVAL;
  
  	user_buf = umap(rp,D,(vir_bytes) m_ptr->TTY_SPEK,(vir_bytes) count);
+ 	if (user_buf == 0) return(E_BAD_ADDR);
+ 
  	if (set)
  		phys_copy(user_buf, our_buf, (long) count);