This matches the semantics the original hush code obtained by using the SA_RESTART flag when installing signal handlers, and avoids error messages about waitpid being interrupted.
The sigprocmask implementation in GNO 2.0.6 libc has bugs that cause it to never actually unblock signals that have been blocked. This was causing many signals to remain blocked when they shouldn't be, particularly after running signal handlers.
This problem combined with a kernel issue (wait() calls won't recognize that a child has finished if SIGCHLD is blocked) to cause hangs in certain conditions.
This patch works around these issues by defining our own non-buggy version of sigprocmask in place of libc's.
These were being reported as strange values because the WEXITSTATUS macro from the GNO headers would erroneously sign-extend them.
Thanks to Kelvin Sherlock for posting an example that demonstrated this problem.
I think this problem is probably due to a bug in GNO's implementation of select().
The workaround is not to use poll (which calls select) when reading a key with no timeout (which is the normal case for command-line input).
This addresses a problem where something invoked in a group or function (e.g. gsh) could change the terminal's pgrp, and this would result in hush getting backgrounded.
We can still get strange behavior when a backgrounded child process changes the pgrp. Trying to deal with this would be inherently racy. Gsh also has problems in this scenario.
The only substantive change is about when simple line input mode is used.
I also bumped the version number and included a GNO-version-specific component.
Hush uses recursion for (at least) parsing nested constructs like { ... }, so it's possible for pathological/malicious scripts to overflow the stack, but this should be enough for just about anything non-pathological (e.g. up to about 10 levels of nested { }).
Based on the following user report:
I ran into an issue where I was seeing a long delay in the scripts called
in udhcp_run_script. I was using an old version of OpenWrt (kamikaze)
and a satellite modem. An NTP script was being called and the modem
would sometimes take a long time to respond to the DNS lookup when
it was offline.
This delay started affecting my lease time. The lease that I would
get from my satellite modem before it was online would be short:
only 60 seconds. The delay with NTP and the modem would typically
be about 18 seconds. This would cause the first DHCP renew request
from dhcpc to be a little late. Under certain circumstances,
I could even see the first DHCP renew to occur after the lease
had expired!
function old new delta
udhcpc_main 2816 2837 +21
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
The --bb options now depends on LONG_OPTS. Omit mentions of --bb from usage
text when LONG_OPTS is disabled.
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
The problem seemed to be that it crashes if the t_intrc special character is set to -1 on a pty. I worked around this by setting it to an obscure control character instead in that case.
The Required_argument macro is only defined when long options are enabled.
Fixes the following build error:
miscutils/nandwrite.c: In function 'nandwrite_main':
miscutils/nandwrite.c:120:10: error: expected ',' or ';' before 'Required_argument'
Reported-by: Christian Kästner <kaestner at cs.cmu.edu>
Signed-off-by: Baruch Siach <baruch at tkos.co.il>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
In vi-mode lineedit tries to detect some escape sequences.
After the ESC it reads the next character to check for certain
values. This read should have a timeout or a user-entered ESC to
switch to command mode doesn't properly handle the next character.
Signed-off-by: Ron Yorston <rmy@tigress.co.uk>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
The support for OA-left/right on GNO uses the OA2META ioctl option to map OA-x to ESC x.
VT100-type terminal emulators have significant variations in what modifier combinations they'll pass through and what escape sequences they produce. Hopefully at least one of them works on just about everything.
This was broken by the change to using CRMOD mode, which actually does mapping on input as well as output. The fix is to set the terminal to "vt100 arrow" mode, which is an undocumented option that translates arrows to vt100-style escape sequences (also used by gsh).
(Note that the earlier patch actually makes us use CRMOD mode most of the time, not non-CRMOD mode as the summary erroneously says.)
This is important because CRMOD mode prevents text from backgrounded programs from being printed properly. It also leaves the terminal in an inappropriate state if hush crashes or is killed.
For the time being, we still switch briefly to CRMOD mode when we want to print just a CR.
Stephen Heumann
Denys Vlasenko
Peter Kümmel
Baruch Siach
Baruch Siach
Ron Yorston