getty: add sleep before initial tcdrain; reduce another sleep from 1 to 0.1s

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 12 insertions, 9 deletions

diff --git a/loginutils/getty.c b/loginutils/getty.c
index e60af3aa3..13b341db5 100644
--- a/loginutils/getty.c
+++ b/loginutils/getty.c
@@ -275,10 +275,13 @@ static void open_tty(const char *tty)
 /* initialize termios settings */
 static void termios_init(struct termios *tp, int speed)
 {
-        /* Flush input and output queues, important for modems! */
-        /* TODO: sleep(1)? Users report lost chars, and I hesitate
-         * to use tcdrain here instead of tcflush */
-        tcflush(0, TCIOFLUSH);
+        /* Flush input and output queues, important for modems!
+         * Users report losing previously queued output chars, and I hesitate
+         * to use tcdrain here instead of tcflush - I imagine it can block.
+         * Using small sleep instead.
+         */
+        usleep(100*1000); /* 0.1 sec */
+        tcflush(STDIN_FILENO, TCIOFLUSH);
 
         /* Set speed if it wasn't specified as "0" on command line. */
         if (speed != B0)
@@ -402,8 +405,8 @@ static char *get_logname(char *logname, unsigned size_logname,
         /* NB: *cp is pre-initialized with init_chardata */
 
         /* Flush pending input (esp. after parsing or switching the baud rate). */
-        sleep(1);
-        tcflush(0, TCIOFLUSH);
+        usleep(100*1000); /* 0.1 sec */
+        tcflush(STDIN_FILENO, TCIOFLUSH);
 
         /* Prompt for and read a login name. */
         logname[0] = '\0';
@@ -659,7 +662,7 @@ int getty_main(int argc UNUSED_PARAM, char **argv)
          * by patching the SunOS kernel variable "zsadtrlow" to a larger value;
          * 5 seconds seems to be a good value.
          */
-        if (tcgetattr(0, &termios) < 0)
+        if (tcgetattr(STDIN_FILENO, &termios) < 0)
                 bb_perror_msg_and_die("tcgetattr");
 
         pid = getpid();
@@ -667,9 +670,9 @@ int getty_main(int argc UNUSED_PARAM, char **argv)
 // FIXME: do we need this? Otherwise "-" case seems to be broken...
         // /* Forcibly make fd 0 our controlling tty, even if another session
         //  * has it as a ctty. (Another session loses ctty). */
-        // ioctl(0, TIOCSCTTY, (void*)1);
+        // ioctl(STDIN_FILENO, TIOCSCTTY, (void*)1);
         /* Make ourself a foreground process group within our session */
-        tcsetpgrp(0, pid);
+        tcsetpgrp(STDIN_FILENO, pid);
 #endif
 
         /* Update the utmp file. This tty is ours now! */