Don't rely on SysV init script in logrotate config

Uploaded into xenial upload queue. Now waiting for SRU verificaition team to approve the upload for rsyslog to start building into xenial-proposed for the testing phase.

Hello Eric, or anyone else affected,

Accepted rsyslog into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/rsyslog/8.16.0-1ubuntu3.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-xenial to verification-done-xenial. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-xenial. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[VERIFICATION XENIAL #1]

It has been brought to my attention the following by a Ubuntu user:
"My team confirms that the package which is in -proposed solves our issue."

This user was having issue doing rsyslog logrotation inside a container which has SYS_PTRACE turned off. Using the systemctl approach fixed their problem.

[VERIFICATION XENIAL #2]

* On a systemd machine:
 $ bash -xv /usr/lib/rsyslog/rsyslog-rotate
#!/bin/sh

if [ -d /run/systemd/system ]; then
    systemctl kill -s HUP rsyslog.service
else
    invoke-rc.d rsyslog rotate > /dev/null
fi
+ '[' -d /run/systemd/system ']'
+ systemctl kill -s HUP rsyslog.service

* /etc/logrotate.d/rsyslog remains exactly the same minus the fact that it now calls this 'rsyslog-rotate' helper to take action depending of systemd or upstart.

* rsyslog rotation works as expected.

This was all tested with rsyslog version: 8.16.0-1ubuntu3.1

[VERIFICATION XENIAL #3]

$ logrotate -vdf /etc/logrotate.conf: works as expected

...
renaming /var/log/syslog.7.gz to /var/log/syslog.8.gz (rotatecount 7, logstart 1, i 7),
renaming /var/log/syslog.6.gz to /var/log/syslog.7.gz (rotatecount 7, logstart 1, i 6),
renaming /var/log/syslog.5.gz to /var/log/syslog.6.gz (rotatecount 7, logstart 1, i 5),
renaming /var/log/syslog.4.gz to /var/log/syslog.5.gz (rotatecount 7, logstart 1, i 4),
renaming /var/log/syslog.3.gz to /var/log/syslog.4.gz (rotatecount 7, logstart 1, i 3),
renaming /var/log/syslog.2.gz to /var/log/syslog.3.gz (rotatecount 7, logstart 1, i 2),
renaming /var/log/syslog.1.gz to /var/log/syslog.2.gz (rotatecount 7, logstart 1, i 1),
renaming /var/log/syslog.0.gz to /var/log/syslog.1.gz (rotatecount 7, logstart 1, i 0),
renaming /var/log/syslog to /var/log/syslog.1
creating new /var/log/syslog mode = 0640 uid = 104 gid = 4
running postrotate script
running script with arg /var/log/syslog: "
  /usr/lib/rsyslog/rsyslog-rotate
"
removing old log /var/log/syslog.8.gz
error: error opening /var/log/syslog.8.gz: No such file or directory
switching euid to 0 and egid to 0

This bug was fixed in the package rsyslog - 8.16.0-1ubuntu3.1

---------------
rsyslog (8.16.0-1ubuntu3.1) xenial; urgency=medium

  * Add d/rsyslog-rotate
  * Modify d/rsyslog.install & d/rsyslog.logrotate
    Don't rely on SysV init script in logrotate config

    Add a small helper to send SIGHUP to rsyslogd to close open log files.
    Use systemctl directly if systemd is the active PID 1. Keep the SysV
    init script as fallback only. (LP: #1821582)

 -- Eric Desrochers <email address hidden> Tue, 19 Mar 2019 22:09:50 -0400

The verification of the Stable Release Update for rsyslog has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.