Fix --with-systemd on Debian-based distributions

[loli10K]

Description

These changes propagate the "--with-systemd" configure option to the RPM spec file, allowing Debian-based distributions to package systemd-related files.

Motivation and Context

Fix #6591

How Has This Been Tested?

Build locally on Debian9 and Fedora26.

root@linux:/usr/src/zfs# lsb_release -a
No LSB modules are available.
Distributor ID:	Debian
Description:	Debian GNU/Linux 9.1 (stretch)
Release:	9.1
Codename:	stretch
root@linux:/usr/src/zfs# dpkg -c zfs_0.7.0-213_amd64.deb | egrep '(init.d|systemd)'
drwxr-xr-x root/root         0 2017-12-14 15:08 ./usr/lib/systemd/
drwxr-xr-x root/root         0 2017-12-14 15:08 ./usr/lib/systemd/system/
-rw-r--r-- root/root       465 2017-12-14 15:07 ./usr/lib/systemd/system/zfs-import-cache.service
-rw-r--r-- root/root       432 2017-12-14 15:07 ./usr/lib/systemd/system/zfs-import-scan.service
-rw-r--r-- root/root       101 2017-12-14 15:07 ./usr/lib/systemd/system/zfs-import.target
-rw-r--r-- root/root       307 2017-12-14 15:07 ./usr/lib/systemd/system/zfs-mount.service
-rw-r--r-- root/root       378 2017-12-14 15:07 ./usr/lib/systemd/system/zfs-share.service
-rw-r--r-- root/root       191 2017-12-14 15:07 ./usr/lib/systemd/system/zfs-zed.service
-rw-r--r-- root/root        76 2017-12-14 15:07 ./usr/lib/systemd/system/zfs.target
drwxr-xr-x root/root         0 2017-12-14 15:08 ./usr/lib/systemd/system-preset/
-rw-r--r-- root/root       208 2017-12-14 15:07 ./usr/lib/systemd/system-preset/50-zfs.preset

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Performance enhancement (non-breaking change which improves efficiency)
• Code cleanup (non-breaking change which makes code smaller or more readable)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation (a change to man pages or other documentation)

Checklist:

• My code follows the ZFS on Linux code style requirements.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.
• All commit messages are properly formatted and contain Signed-off-by.
• Change has been approved by a ZFS on Linux member.

[loli10K]

I had to move this inside the first %if 0%{?rhel}%{?fedora}%{?suse_version} condition, the rpm binary on my Debian9 doesn't know how to handle the "BuildRequires" tag (probably because we're missing the rpmdb on Debian-based distros).

This is from gdb attached to the rpmbuild process:

Breakpoint 1, unsatisfiedDepend (ts=0x555555797b10, dcache=0x5555557eb770, dep=0x5555557e9a10) at depends.c:784
warning: Source file is more recent than executable.
784		rc = 1;
(gdb) bt
#0  unsatisfiedDepend (ts=0x555555797b10, dcache=0x5555557eb770, dep=0x5555557e9a10) at depends.c:784
#1  0x00007ffff7b8823f in checkDS (ts=0x555555797b10, dcache=0x5555557eb770, te=0x5555557d0120, pkgNEVRA=0x5555557cb280 "zfs-0.7.0-213_gf6940bb9e.x86_64", ds=0x5555557e9a10, tscolor=3) at depends.c:808
#2  0x00007ffff7b8891f in rpmtsCheck (ts=0x555555797b10) at depends.c:936
#3  0x00007ffff771b4c7 in rpmSpecCheckDeps (ts=0x555555797b10, spec=0x5555557982a0) at spec.c:322
#4  0x0000555555556b7f in checkSpec (ts=0x555555797b10, spec=0x5555557982a0) at rpmbuild.c:234
#5  0x000055555555758d in buildForTarget (ts=0x555555797b10, arg=0x55555578ac50 "SPECS/zfs.spec", ba=0x55555575a9e0 <rpmBTArgs>) at rpmbuild.c:453
#6  0x00005555555576ed in build (ts=0x555555797b10, arg=0x55555578ac50 "SPECS/zfs.spec", ba=0x55555575a9e0 <rpmBTArgs>, rcfile=0x0) at rpmbuild.c:490
#7  0x0000555555557cc2 in main (argc=18, argv=0x7fffffffea98) at rpmbuild.c:626
(gdb) p *dep
$1 = {pool = 0x5555557d0240, Type = 0x7ffff7bc1e61 "Requires", DNEVR = 0x555555826940 "R systemd", N = 0x5555557e9a70, EVR = 0x5555557e9ab0, Flags = 0x5555557e9ad0, Color = 0x0, tagN = 1049, Count = 1, 
  instance = 0, i = 0, nopromote = 1, nrefs = 1, ti = 0x0}
(gdb) fin
Run till exit from #0  unsatisfiedDepend (ts=0x555555797b10, dcache=0x5555557eb770, dep=0x5555557e9a10) at depends.c:784
0x00007ffff7b8823f in checkDS (ts=0x555555797b10, dcache=0x5555557eb770, te=0x5555557d0120, pkgNEVRA=0x5555557cb280 "zfs-0.7.0-213_gf6940bb9e.x86_64", ds=0x5555557e9a10, tscolor=3) at depends.c:808
808		if (unsatisfiedDepend(ts, dcache, ds) == is_problem)
Value returned is $2 = 1
(gdb) 

[behlendorf]

@loli10K you can add the following changes to this PR to resolve the CentOS 6 / Amazon build failures. Since your patch passes the configure results to rpmbuild it overrides default logic in the spec file so we need to pass in the correct setting. This patch adds a basic check to see if systemd is installed in the build environment.

I'd also suggest using --with systemd and --without systemd which are understood by rpmbuild and handled by the %bcond_with* macro.

diff --git a/config/user-systemd.m4 b/config/user-systemd.m4
index dae5b07..0750862 100644
--- a/config/user-systemd.m4
+++ b/config/user-systemd.m4
@@ -2,7 +2,8 @@ AC_DEFUN([ZFS_AC_CONFIG_USER_SYSTEMD], [
        AC_ARG_ENABLE(systemd,
                AC_HELP_STRING([--enable-systemd],
                [install systemd unit/preset files [[default: yes]]]),
-               [],enable_systemd=yes)
+               [enable_systemd=$enableval],
+               [enable_systemd=check])
 
        AC_ARG_WITH(systemdunitdir,
                AC_HELP_STRING([--with-systemdunitdir=DIR],
@@ -19,14 +20,22 @@ AC_DEFUN([ZFS_AC_CONFIG_USER_SYSTEMD], [
                [install systemd module load files into dir [[/usr/lib/modules-load.d]]]),
                systemdmoduleloaddir=$withval,systemdmodulesloaddir=/usr/lib/modules-load.d)
 
+       AS_IF([test "x$enable_systemd" = xcheck], [
+               AS_IF([systemctl --version >/dev/null 2>&1],
+                       [enable_systemd=yes],
+                       [enable_systemd=no])
+       ])
+
+        AC_MSG_CHECKING(for systemd support)
+        AC_MSG_RESULT([$enable_systemd])
 
        AS_IF([test "x$enable_systemd" = xyes], [
                ZFS_INIT_SYSTEMD=systemd
                ZFS_MODULE_LOAD=modules-load.d
-               DEFINE_SYSTEMD='--define "_systemd 1" --define "_unitdir $(systemdunitdir)" --define "_presetdir $(systemdpresetdir)"'
+               DEFINE_SYSTEMD='--with systemd --define "_unitdir $(systemdunitdir)" --define "_presetdir $(systemdpresetdir)"'
                modulesloaddir=$systemdmodulesloaddir
        ],[
-               DEFINE_SYSTEMD=''
+               DEFINE_SYSTEMD='--without systemd'
        ])
 
        AC_SUBST(ZFS_INIT_SYSTEMD)

[codecov]

Codecov Report

Merging #6963 into master will increase coverage by 0.32%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           master   #6963      +/-   ##
=========================================
+ Coverage   75.17%   75.5%   +0.32%     
=========================================
  Files         296     296              
  Lines       95453   95453              
=========================================
+ Hits        71759   72069     +310     
+ Misses      23694   23384     -310

Flag	Coverage Δ
#kernel	74.83% <ø> (+0.34%)	⬆️
#user	67.9% <ø> (+0.45%)	⬆️

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