Re: [PATCH] tty: Add EXTPROC support for LINEMODE

[Howard Chu <hyc@symas.com>]

hyc@symas.com wrote:
> This patch is against the 2.6.34 source.
> @@ -1632,6 +1638,11 @@ static int copy_from_read_buf(struct tty_struct *tty,
>   		spin_lock_irqsave(&tty->read_lock, flags);
>   		tty->read_tail = (tty->read_tail + n)&  (N_TTY_BUF_SIZE-1);
>   		tty->read_cnt -= n;
> +		/* Check if last character is EOF */
> +		if (L_EXTPROC(tty)&&  tty->icanon) {
> +			if (!tty->read_cnt&&  (*b)[n-1] == EOF_CHAR(tty))
> +				n--;
> +		}
>   		spin_unlock_irqrestore(&tty->read_lock, flags);
>   		*b += n;
>   		*nr -= n;

This bit is wrong, only a naked EOF all by itself should be dropped. Should 
add this to the above:

diff --git a/drivers/char/n_tty.c b/drivers/char/n_tty.c
index bba123e..428f4fe 100644
--- a/drivers/char/n_tty.c
+++ b/drivers/char/n_tty.c
@@ -1638,8 +1638,8 @@ static int copy_from_read_buf(struct tty_struct *tty,
                 spin_lock_irqsave(&tty->read_lock, flags);
                 tty->read_tail = (tty->read_tail + n) & (N_TTY_BUF_SIZE-1);
                 tty->read_cnt -= n;
-               /* Check if last character is EOF */
-               if (L_EXTPROC(tty) && tty->icanon) {
+               /* Turn single EOF into zero-length read */
+               if (L_EXTPROC(tty) && tty->icanon && n == 1) {
                         if (!tty->read_cnt && (*b)[n-1] == EOF_CHAR(tty))
                                 n--;
                 }


-- 
   -- Howard Chu
   CTO, Symas Corp.           http://www.symas.com
   Director, Highland Sun     http://highlandsun.com/hyc/
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