[PATCH] n-tty-output-bells-immediately

[Joe Peterson]

 This patch causes "bell" (^G) characters (invoked when the input buffer
is full) to be immediately output rather than filling the echo buffer.

This is especially a problem when the tty is stopped and buffers fill, since
the bells do not serve their purpose of immediate notification that the
buffer cannot take further input, and they will flush all at once when the
tty is restarted.

Signed-off-by: Joe Peterson <joe@xxxxxxxxxxx>
---

diff -Nurp b/drivers/char/n_tty.c c/drivers/char/n_tty.c
--- b/drivers/char/n_tty.c	2008-10-22 18:14:38.083337970 -0600
+++ c/drivers/char/n_tty.c	2008-10-22 18:14:56.573340597 -0600
@@ -872,7 +872,7 @@ static void eraser(unsigned char c, stru
 
 	/* FIXME: locking needed ? */
 	if (tty->read_head == tty->canon_head) {
-		/* echo_char_raw('\a', tty); */ /* what do you think? */
+		/* process_output('\a', tty); */ /* what do you think? */
 		return;
 	}
 	if (c == ERASE_CHAR(tty))
@@ -1148,10 +1148,8 @@ static inline void n_tty_receive_char(st
 		parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0;
 		if (tty->read_cnt >= (N_TTY_BUF_SIZE - parmrk - 1)) {
 			/* beep if no space */
-			if (L_ECHO(tty)) {
-				echo_char_raw('\a', tty);
-				process_echoes(tty);
-			}
+			if (L_ECHO(tty))
+				process_output('\a', tty);
 			return;
 		}
 		if (L_ECHO(tty)) {
@@ -1255,10 +1253,8 @@ send_signal:
 		}
 		if (c == '\n') {
 			if (tty->read_cnt >= N_TTY_BUF_SIZE) {
-				if (L_ECHO(tty)) {
-					echo_char_raw('\a', tty);
-					process_echoes(tty);
-				}
+				if (L_ECHO(tty))
+					process_output('\a', tty);
 				return;
 			}
 			if (L_ECHO(tty) || L_ECHONL(tty)) {
@@ -1280,10 +1276,8 @@ send_signal:
 			parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty))
 				 ? 1 : 0;
 			if (tty->read_cnt >= (N_TTY_BUF_SIZE - parmrk)) {
-				if (L_ECHO(tty)) {
-					echo_char_raw('\a', tty);
-					process_echoes(tty);
-				}
+				if (L_ECHO(tty))
+					process_output('\a', tty);
 				return;
 			}
 			/*
@@ -1320,10 +1314,8 @@ handle_newline:
 	parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0;
 	if (tty->read_cnt >= (N_TTY_BUF_SIZE - parmrk - 1)) {
 		/* beep if no space */
-		if (L_ECHO(tty)) {
-			echo_char_raw('\a', tty);
-			process_echoes(tty);
-		}
+		if (L_ECHO(tty))
+			process_output('\a', tty);
 		return;
 	}
 	if (L_ECHO(tty)) {