This also cleans up several locations that could try to repeatedly call
close(). See prior commit for further details on why that is best avoided.

Quoting part of the close() man page:

       Retrying  the  close() after a failure return is the wrong thing to do,
       since this may cause a reused file descriptor from another thread to be
       closed.   This  can  occur because the Linux kernel always releases the
       file descriptor early in the close operation, freeing it for reuse; the
       steps that may return an error, such as flushing data to the filesystem
       or device, occur only later in the close operation.

Set DISPLAY to SLURM_X11_SETUP_FAILED to make it clear that the
tunnel setup has failed. This at least gives the user a hint as to
why their X11 apps aren't working, although further refinement should be
done later:

tim@zoidberg:~$ srun --x11 xclock
Error: Can't open display: SLURM_X11_SETUP_FAILED
srun: error: node001: task 0: Exited with exit code 1

Creates a local XAUTHORITY file in TmpFS on the node, and deletes
it upon job termination. This avoids file locking contention on
~/.Xauthority in the users home directory.

Bug 3647.

Build out sufficient plumbing such that a temporary XAUTHORITY file
can be used that is local to the compute node, thus avoiding lock
contention on ~/.Xauthority on parallel filesystems.

This commit only includes the requisite plumbing to pass this around.

If this is not used, a null string results, and the XAUTHORITY env var
will not be forced into the user environment.

Add support and fix the modified API call in pam_slurm_adopt while here.

Bug 3647.

Update slurm.spec and slurm.spec-legacy as well.

The lower limit of 1024 may be too short for srun with large-scale
jobs, and lead to problems processing task completion messages in a
timely fashion.

Rather than adjust that, unify the two separate macros into
SLURM_DEFAULT_LISTEN_BACKLOG with the higer 4096 value.

Bug 5164.

Without Delegate=yes, systemd will "fix" the cgroup hierarchies whenever
'systemctl daemon-reload' is called, which will then remove any
restrictions placed on memory or device access for a given job.

This is a problem especially since 'systemctl daemon-reload' may be called
automatically by rpm/yum or a variety of config file mangers, leading to
jobs escaping from slurmd/slurmstepd's control.

This setting should work for systemd versions >= 205.
https://www.freedesktop.org/wiki/Software/systemd/ControlGroupInterface/

Bug 5292.

addresses problem reported by clang

bug introduced in commit a7d9313d

When a job with time_end=0 and TRES null exists from an association that is
currently inside a reservation, the hourly rollup segfaults.

Bug 5143

And from underlying slurm_msg_sendto_timeout call as well.

Add function to clear total_gres at start of scheduling cycle
Modify logic to avoid overflow on gpu counter

As reported by Avalon Johnson on slurm-users
https://groups.google.com/forum/#!topic/slurm-users/BsMQ7Uk1PLw
Bug 5287.

bug 4373, comment #24

Removed the sentence which incorrectly stated that when not using the
gres flag enforce-binding option, cpus other than the ones defined in gres.conf
could be used for a gpu.

Bug 5189

srun was already fixed in b7053bda (Bug 3294).

Bug 5126

bug 5189

Add salloc/sbatch/srun option of --gres-flags=disable-binding to disable
    filtering of CPUs with respect to generic resource locality. This option is
    currently required to use more CPUs than are bound to a GRES (i.e. if a GPU
    is bound to the CPUs on one socket, but resources on more than one socket
    are required to run the job). This option may permit a job to be allocated
    resources sooner than otherwise possible, but may result in lower job
    performance.
bug 5189

'have_innodb' is deprecated.

Bug 5317.

Cleanup printf formaters and ensure they match the types:
%zu for size_t
%zd for ssize_t

Bug 5417.

When printing arrays in squeue and setting the SLURM_BITSTR_LEN variable to 0
or to NULL, the length of the output defaulted to 64, when the documentation
says it will default to "unlimited". This patch fixes this situation.

Bug 5440

Because of a bug in the some versions of the Linux kernel, disable
constraining kernel memory space with cgroups by default.

Bug 5223.

Coverity CID 186991

Logic was switched around in 17.11, enable_user_top is now the
correct option.

Bug 5165.

This is not working reliably even when setting
SchedulerParameters=enable_hetero_steps and/or using OpenMPI with Slurm's
mpi/pmi2, as it was previously documented.

Bug 5309.