From 5c67885a2660e6403402851f912dd01331cb45d4 Mon Sep 17 00:00:00 2001
From: Ed Schouten <ed@FreeBSD.org>
Date: Sun, 23 Aug 2009 08:04:40 +0000
Subject: [PATCH] Add ttydisc_rint_simple().

I noticed several drivers in our tree don't actually care about parity
and framing, such as pts(4), snp(4) (and my partially finished console
driver). Instead of duplicating a lot of code, I think we'd better add a
utility function for those drivers to quickly process a buffer of input.

Also change pts(4) and snp(4) to use this function.
---
 sys/dev/snp/snp.c      | 11 +++--------
 sys/kern/tty_pts.c     | 25 ++++++-------------------
 sys/kern/tty_ttydisc.c | 16 ++++++++++++++++
 sys/sys/ttydisc.h      |  1 +
 4 files changed, 26 insertions(+), 27 deletions(-)

diff --git a/sys/dev/snp/snp.c b/sys/dev/snp/snp.c
index fcc70a5d84f3..37d996563f94 100644
--- a/sys/dev/snp/snp.c
+++ b/sys/dev/snp/snp.c
@@ -192,7 +192,7 @@ snp_write(struct cdev *dev, struct uio *uio, int flag)
 {
 	struct snp_softc *ss;
 	struct tty *tp;
-	int error, len, i;
+	int error, len;
 	char in[SNP_INPUT_BUFSIZE];
 
 	error = devfs_get_cdevpriv((void **)&ss);
@@ -223,14 +223,9 @@ snp_write(struct cdev *dev, struct uio *uio, int flag)
 		 * because we shouldn't bail out when we're running
 		 * close to the watermarks.
 		 */
-		if (ttydisc_can_bypass(tp)) {
-			ttydisc_rint_bypass(tp, in, len);
-		} else {
-			for (i = 0; i < len; i++)
-				ttydisc_rint(tp, in[i], 0);
-		}
-
+		ttydisc_rint_simple(tp, in, len);
 		ttydisc_rint_done(tp);
+
 		tty_unlock(tp);
 	}
 
diff --git a/sys/kern/tty_pts.c b/sys/kern/tty_pts.c
index d5045c17b4d9..c77cf2a1d828 100644
--- a/sys/kern/tty_pts.c
+++ b/sys/kern/tty_pts.c
@@ -215,25 +215,12 @@ ptsdev_write(struct file *fp, struct uio *uio, struct ucred *active_cred,
 		 */
 		MPASS(iblen > 0);
 		do {
-			if (ttydisc_can_bypass(tp)) {
-				/* Store data at once. */
-				rintlen = ttydisc_rint_bypass(tp,
-				    ibstart, iblen);
-				ibstart += rintlen;
-				iblen -= rintlen;
-
-				if (iblen == 0) {
-					/* All data written. */
-					break;
-				}
-			} else {
-				error = ttydisc_rint(tp, *ibstart, 0);
-				if (error == 0) {
-					/* Character stored successfully. */
-					ibstart++;
-					iblen--;
-					continue;
-				}
+			rintlen = ttydisc_rint_simple(tp, ibstart, iblen);
+			ibstart += rintlen;
+			iblen -= rintlen;
+			if (iblen == 0) {
+				/* All data written. */
+				break;
 			}
 
 			/* Maybe the device isn't used anyway. */
diff --git a/sys/kern/tty_ttydisc.c b/sys/kern/tty_ttydisc.c
index debaa1cc1e90..d79a2b761d56 100644
--- a/sys/kern/tty_ttydisc.c
+++ b/sys/kern/tty_ttydisc.c
@@ -1044,6 +1044,22 @@ ttydisc_rint(struct tty *tp, char c, int flags)
 	return (0);
 }
 
+size_t
+ttydisc_rint_simple(struct tty *tp, const void *buf, size_t len)
+{
+	const char *cbuf;
+
+	if (ttydisc_can_bypass(tp))
+		return (ttydisc_rint_bypass(tp, buf, len));
+
+	for (cbuf = buf; len-- > 0; cbuf++) {
+		if (ttydisc_rint(tp, *cbuf, 0) != 0)
+			break;
+	}
+
+	return (cbuf - (const char *)buf);
+}
+
 size_t
 ttydisc_rint_bypass(struct tty *tp, const void *buf, size_t len)
 {
diff --git a/sys/sys/ttydisc.h b/sys/sys/ttydisc.h
index 2ea54666c56a..74a1a0ed927e 100644
--- a/sys/sys/ttydisc.h
+++ b/sys/sys/ttydisc.h
@@ -52,6 +52,7 @@ void	ttydisc_optimize(struct tty *tp);
 void	ttydisc_modem(struct tty *tp, int open);
 #define ttydisc_can_bypass(tp) ((tp)->t_flags & TF_BYPASS)
 int	ttydisc_rint(struct tty *tp, char c, int flags);
+size_t	ttydisc_rint_simple(struct tty *tp, const void *buf, size_t len);
 size_t	ttydisc_rint_bypass(struct tty *tp, const void *buf, size_t len);
 void	ttydisc_rint_done(struct tty *tp);
 size_t	ttydisc_rint_poll(struct tty *tp);