agetty: add -c to reuse cflags

The agetty command resets terminal cflags setting. The -c option
disables this behavior and serial setting from kernel is used.

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/login-utils/agetty.8 b/login-utils/agetty.8
index 53037dda58369c0155de756e5a66da885396be81..084086fda728c5641483e3808085d481dbe7b783 100644 (file)
--- a/login-utils/agetty.8
+++ b/login-utils/agetty.8
@@ -3,7 +3,7 @@
 agetty \- alternative Linux getty
 
 .SH SYNOPSIS
-.BR "agetty " [\-8ihLmnsUw]
+.BR "agetty " [\-c8ihLmnsUw]
 .RI "[-f " issue_file ]
 .RI "[-l " login_program ]
 .RI "[-I " init ]
@@ -82,6 +82,10 @@ whatever init(8) may have set, and is inherited by login and the shell.
 .fi
 .ad
 .TP
+\-c
+Don't reset terminal cflags (control modes). See \fItermios(3)\fP for more
+details.
+.TP
 \-8
 Assume that the tty is 8-bit clean, hence disable parity detection.
 .TP

diff --git a/login-utils/agetty.c b/login-utils/agetty.c
index 254194816495a10004e1b42ee920c8d82b1fb2bf..a6e249986b14612258a4f3bfed9bac6b273ce641 100644 (file)
--- a/login-utils/agetty.c
+++ b/login-utils/agetty.c
@@ -134,6 +134,7 @@ struct options {
 #define F_NOPROMPT     (1<<7)          /* don't ask for login name! */
 #define F_LCUC         (1<<8)          /* Support for *LCUC stty modes */
 #define F_KEEPSPEED    (1<<9)          /* Follow baud rate from kernel */
+#define F_KEEPCFLAGS   (1<<10)         /* Reuse c_cflags setup from kernel */
 
 /* Storage for things detected while the login name was read. */
 
@@ -374,8 +375,11 @@ parse_args(argc, argv, op)
     extern int optind;                 /* getopt */
     int     c;
 
-    while (isascii(c = getopt(argc, argv, "8I:LH:f:hil:mst:wUn"))) {
+    while (isascii(c = getopt(argc, argv, "8cI:LH:f:hil:mst:wUn"))) {
        switch (c) {
+       case 'c':
+           op->flags |= F_KEEPCFLAGS;
+           break;
        case '8':
            op->eightbits = 1;
            break;
@@ -709,7 +713,8 @@ termio_init(tp, op)
     /* flush input and output queues, important for modems! */
     (void) tcflush(0, TCIOFLUSH);
 
-    tp->c_cflag = CS8 | HUPCL | CREAD | (tp->c_cflag & CLOCAL);
+    if (!(op->flags & F_KEEPCFLAGS))
+       tp->c_cflag = CS8 | HUPCL | CREAD | (tp->c_cflag & CLOCAL);
 
     if (!(op->flags & F_KEEPSPEED)) {
            cfsetispeed(tp, op->speeds[FIRST_SPEED]);