From 5055a9f98999d3a6c2f4d043a85f6c2d6fb7eaf2 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Fri, 14 May 2010 04:08:20 +0200 Subject: [PATCH] cttyhack: don't do anything if ctty is already available function old new delta cttyhack_main 244 269 +25 Signed-off-by: Denys Vlasenko --- shell/cttyhack.c | 43 ++++++++++++++++++++++++++----------------- 1 file changed, 26 insertions(+), 17 deletions(-) diff --git a/shell/cttyhack.c b/shell/cttyhack.c index 572a3af03..bde2acdc9 100644 --- a/shell/cttyhack.c +++ b/shell/cttyhack.c @@ -53,23 +53,32 @@ int cttyhack_main(int argc UNUSED_PARAM, char **argv) } strcpy(console, "/dev/tty"); - if (ioctl(0, TIOCGSERIAL, &u.sr) == 0) { - /* this is a serial console */ - sprintf(console + 8, "S%d", u.sr.line); - } else if (ioctl(0, VT_GETSTATE, &u.vt) == 0) { - /* this is linux virtual tty */ - sprintf(console + 8, "S%d" + 1, u.vt.v_active); - } - - if (console[8]) { - fd = xopen(console, O_RDWR); - //bb_error_msg("switching to '%s'", console); - dup2(fd, 0); - dup2(fd, 1); - dup2(fd, 2); - while (fd > 2) close(fd--); - /* Some other session may have it as ctty. Steal it from them */ - ioctl(0, TIOCSCTTY, 1); + fd = open(console, O_RDWR); + if (fd >= 0) { + /* We already have ctty, nothing to do */ + close(fd); + } else { + /* We don't have ctty (or don't have "/dev/tty" node...) */ + if (ioctl(0, TIOCGSERIAL, &u.sr) == 0) { + /* this is a serial console */ + sprintf(console + 8, "S%d", u.sr.line); + } else if (ioctl(0, VT_GETSTATE, &u.vt) == 0) { + /* this is linux virtual tty */ + sprintf(console + 8, "S%d" + 1, u.vt.v_active); + } + if (console[8]) { + fd = xopen(console, O_RDWR); + //bb_error_msg("switching to '%s'", console); + dup2(fd, 0); + dup2(fd, 1); + dup2(fd, 2); + while (fd > 2) + close(fd--); + /* Some other session may have it as ctty, + * steal it from them: + */ + ioctl(0, TIOCSCTTY, 1); + } } BB_EXECVP(argv[0], argv);