agetty refresh prompt (/etc/issue file etc.) when requested by inotify
or netlink. For this purpose we monitor some file descriptors by
select().
The terminal input file descriptor is switched to non-canonical mode before
select(). The goal is to be informed about user activity before
new-line. The FD is immediately switched back to canonical mode when
activity is detected. The side effect is that all not-read-yet chars in
the input buffer are lost ... so we need to call read() before switch
to canonical mode to save the chars.
The original implementation has been based on TIOCSTI ioctl. It
returns already read chars back to the terminal input buffer to make
them useful for canonical mode. The problem was race (agetty writes to
input buffer in the same time as user) and result was reordered chars
in login name... so useless.
This issue has been later fixed by extra buffer (commit
790119b885) for already read data. And
TIOCSTI ioctl has been removed. Unfortunately this solution is also
wrong, because the buffer is maintained only by agetty and
inaccessible for terminal when user edit (by DEL/CTRL^U) login name in
canonical mode.
The solution is simple -- just don't try to be smart and keep terminal
in canonical mode all time (so terminal controls DEL, CTRL^U, etc) and
flush input buffer (=discard unread data) and ask user for login name
again after prompt reload.
The agetty reload is very rarely situation and for user it's pretty
obvious that he has to type login name again (as all terminal has been
clear+redraw).
Addresses: https://github.com/karelzak/util-linux/issues/454
Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=1464148
Signed-off-by: Karel Zak <kzak@redhat.com>
(Original patch and commit message edited by Rudi.)
gcc-7 adds -Wimplicit-fallthrough=3 to our default flag -Wextra.
This warning can be silenced by using comment /* fallthrough */
which is also recognized by other tools like coverity. There are
also other valid comments (see man gcc-7) but we consolidate this
style now.
We could have also used __attribute__((fallthrough)) but the comment
looks nice and does not need to be ifdef'ed for compatibility.
Reference: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=7652
Reference: https://developers.redhat.com/blog/2017/03/10/wimplicit-fallthrough-in-gcc-7/
Reviewed-by: Ruediger Meier <ruediger.meier@ga-group.nl>
Suggested-by: Karel Zak <kzak@redhat.com>
Signed-off-by: Sami Kerola <kerolasa@iki.fi>
Without this change an attempt to remove hostname printing required following
rather clumsy agetty invocation.
/sbin/agetty --nohostname --login-options '/bin/login -H -- \u'
After the change --nohostname behaves similar way with --host option, that
is when combined with --remote the effect is passed to login(1).
Signed-off-by: Sami Kerola <kerolasa@iki.fi>
The current agetty uses TIOCSTI ioctl to return already read chars
from login name back to the terminal (without read() before
tcsetattr() we will lost data already written by user). The ioctl
based solution is fragile due to race -- we can return chars when
terminal already contains another new chars. The result is reordered
chars in login name.
The solution is to use extra buffer for already read data.
Reported-by: Michael Tretter <m.tretter@pengutronix.de>
Signed-off-by: Karel Zak <kzak@redhat.com>
text-utils/tailf.c:69:21: warning: Using plain integer as NULL pointer
Since many 'struct option' has used zero as NULL make them more readable in
same go by reindenting, and using named argument requirements.
Reference: https://lwn.net/Articles/93577/
Signed-off-by: Sami Kerola <kerolasa@iki.fi>
Now the build will fail on many non-Linux systems because
utmpx.h is available everywhere but we still use non-POSIX
features. We'll fix this next commit.
Signed-off-by: Ruediger Meier <ruediger.meier@ga-group.nl>
_HAVE_UT_TV is glibc only. Moreover we want to move to utmpx where
timeval is standard.
Now utmp/subsecond (1173d0a6) should work on all supported systems.
CC: Sami Kerola <kerolasa@iki.fi>
Signed-off-by: Ruediger Meier <ruediger.meier@ga-group.nl>
Fix various typos in error messages, warnings, debug strings,
comments and names of static functions.
Signed-off-by: Sebastian Rasmussen <sebras@gmail.com>
The plymouth support depends on Linux specific SOCK_* flags and all
the feature is probably unnecessary in some cases (non-plymouth
distros, etc.)
Signed-off-by: Karel Zak <kzak@redhat.com>
for stopping plymouthd. That do not depend on the existence of
the plymouth binary if it e.g. becomes uninstalled or an other
service is providing plymouthd facilities.
[kzak@redhat.com: - fix compiler warnings [-Wpointer-sign]
- use sizeof() for write_all()
- cast to char* for read_all]
Signed-off-by: Werner Fink <werner@suse.de>
Signed-off-by: Karel Zak <kzak@redhat.com>
agetty uses NETLINK_ROUTE to be notified about network interface
changes. Unfortunately, the code that monitor the netlink FD does not
increment number of the monitored file descriptors when call
select(2), so the netlink notifications are invisible for agetty.
Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=1278906
Signed-off-by: Karel Zak <kzak@redhat.com>
Several of the /etc/issue escape codes such as \4 and \6 depend on
the current addresses of the system that can change after the agetty
prompt is displayed. This can cause stale data to be displayed
when a user looks at a VT, especially in cases of DHCP racing with
system start up.
Similar to the --reload mechanism, if we're displaying an address
in the issue output, and the user hasn't typed anything yet: then
redisplay the prompt with the new address.
We use netlink to watch for address changes. We only open the netlink
socket if we display an address in the issue file.
The current "agetty --reload" implementation does not refresh issue
file output on autologin. Let's support this use-case too.
Reported-by: Sitsofe Wheeler <sitsofe@gmail.com>
Signed-off-by: Karel Zak <kzak@redhat.com>
agetty monitors /run/agetty.reload file, unfortunately if the file
does not exist when agetty starts up then "agetty" --reload does not
work. This patch forces agetty to create the file before inotify
is enabled.
Reported-by: Sitsofe Wheeler <sitsofe@gmail.com>
Signed-off-by: Karel Zak <kzak@redhat.com>
http://www.freedesktop.org/software/systemd/man/os-release.html
The file /etc/os-release takes precedence over /usr/lib/os-release.
Applications should check for the former, and exclusively use its data
if it exists, and only fall back to /usr/lib/os-release if it is
missing.
Reported-by: Dimitri John Ledkov <dimitri.j.ledkov@intel.com>
Signed-off-by: Karel Zak <kzak@redhat.com>
This adds a concise description of a tool to its usage text.
A first form of this patch was proposed by Steven Honeyman
(see http://www.spinics.net/lists/util-linux-ng/msg09994.html).
Signed-off-by: Benno Schulenberg <bensberg@justemail.net>
It seems better to warn about --reload in ./configure if futimens or
inotify_init1 are missing.
The patch also replaces futimes() with futimens() to make the code
compatible with Uclibc.
Addresses: https://github.com/karelzak/util-linux/issues/133
Signed-off-by: Karel Zak <kzak@redhat.com>
Fix command line parsing to not ignore term setting if no baud
specified, for example:
/sbin/agetty ttyS0 vt100
Signed-off-by: Karel Zak <kzak@redhat.com>
* makes speeds table usage more robust
* don't call next_speed() for empty speeds table to avoid division by zero
* default to 9600 when port baud unspecified
Addresses: https://github.com/karelzak/util-linux/pull/131
Signed-off-by: Karel Zak <kzak@redhat.com>
Add an 'agetty --reload' command which asks all running agetty
commands to display their prompts again.
Several of the /etc/issue escape codes such as \4 and \S depend on
variable data which can change after the agetty prompt is displayed.
This can cause stale data to be displayed when a user looks at a VT,
especially in cases of DHCP racing with system start up.
We never want this to occur once the user has started typing a
user name. So we detect when the user starts typing, after which
no further reprompting occurs after that point.
[kzak@redhat.com: - add #ifdefs to make it usable on non-inotify systems,
- use futimens() with NULL timespec
- add --reaload to usage()]
Signed-off-by: Stef Walter <stefw-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Signed-off-by: Karel Zak <kzak@redhat.com>
Karel Zak
Sami Kerola
Matthias Gerstner
Yuri Chornoivan
Ruediger Meier
Sebastian Rasmussen
Werner Fink
Yuriy M. Kaminskiy
Stef Walter
Benno Schulenberg
Christoph Egger
Stef Walter
Samuel Thibault
Benjamin Robin