build: meson: support $DESTDIR in installation script

Adapt the meson post-installation script to handle the $DESTDIR
variable supplied by user to specify the installation target
directory. While at it, convert the script to shell because it seems
simpler to me.

(cherry picked from commit 98b4a19a53)

Makefile.am

@@ -4744,7 +4744,6 @@ EXTRA_DIST += \
 	valgrind.suppressions \
 	meson.build \
 	meson_options.txt \
-	meson_post_install.py \
 	config.h.meson \
 	config-extra.h.meson \
 	docs/meson.build \
@@ -4785,6 +4784,7 @@ EXTRA_DIST += \
 	tools/check-exports.sh \
 	tools/create-exports-NetworkManager.sh \
 	tools/debug-helper.py \
+	tools/meson-post-install.sh \
 	tools/run-nm-test.sh \
 	tools/test-networkmanager-service.py \
 	tools/test-sudo-wrapper.sh \

meson.build

@@ -896,7 +896,7 @@ configure_file(
 )
 
 meson.add_install_script(
-  'meson_post_install.py',
+  join_paths('tools', 'meson-post-install.sh'),
   nm_datadir,
   nm_bindir,
   nm_pkgconfdir,

meson_post_install.py

@@ -1,46 +0,0 @@
-#!/usr/bin/env python3
-
-import os
-import sys
-
-if not os.environ.get('DESTDIR'):
-  datadir = sys.argv[1]
-  bindir = sys.argv[2]
-  pkgconfdir = sys.argv[3]
-  pkglibdir = sys.argv[4]
-  localstatedir = sys.argv[5]
-
-  completions_dir = os.path.join(datadir, 'bash-completion', 'completions')
-  os.rename(os.path.join(completions_dir, 'nmcli-completion'), os.path.join(completions_dir, 'nmcli'))
-
-  nmtui_alias = ['nmtui-connect', 'nmtui-edit', 'nmtui-hostname']
-  src = os.path.join(bindir, 'nmtui')
-  [os.symlink(src, os.path.join(bindir, dst))
-   for dst in nmtui_alias]
-
-  dst_dirs = [
-    os.path.join(pkgconfdir, 'conf.d'),
-    os.path.join(pkgconfdir, 'system-connections'),
-    os.path.join(pkgconfdir, 'dispatcher.d', 'no-wait.d'),
-    os.path.join(pkgconfdir, 'dispatcher.d', 'pre-down.d'),
-    os.path.join(pkgconfdir, 'dispatcher.d', 'pre-up.d'),
-    os.path.join(pkgconfdir, 'dnsmasq.d'),
-    os.path.join(pkgconfdir, 'dnsmasq-shared.d'),
-    os.path.join(pkglibdir, 'conf.d'),
-    os.path.join(pkglibdir, 'VPN'),
-    os.path.join(localstatedir, 'lib', 'NetworkManager')
-  ]
-  [os.makedirs(dst_dir)
-   for dst_dir in dst_dirs
-   if not os.path.exists(dst_dir)]
-
-  if sys.argv[6] == 'install_docs':
-    mandir = sys.argv[7]
-
-    src = os.path.join(mandir, 'man1', 'nmtui.1')
-    [os.symlink(src, os.path.join(mandir, 'man1', dst + '.1'))
-     for dst in nmtui_alias]
-
-    src = os.path.join(mandir, 'man5', 'NetworkManager.conf.5')
-    dst = os.path.join(mandir, 'man5', 'nm-system-settings.conf.5')
-    os.symlink(src, dst)

tools/meson-post-install.sh

@@ -0,0 +1,44 @@
+#!/bin/sh
+
+datadir=$1
+bindir=$2
+pkgconfdir=$3
+pkglibdir=$4
+localstatedir=$5
+
+[ -n "$DESTDIR" ] && DESTDIR=${DESTDIR%%/}/
+
+if [ -f "${DESTDIR}${datadir}/bash-completion/completions/nmcli-completion" ]; then
+    mv "${DESTDIR}${datadir}/bash-completion/completions/nmcli-completion" \
+       "${DESTDIR}${datadir}/bash-completion/completions/nmcli"
+fi
+
+if [ -x "${DESTDIR}${bindir}/nmtui" ]; then
+    for alias in nmtui-connect nmtui-edit nmtui-hostname; do
+        ln -sf nmtui "${DESTDIR}${bindir}/$alias"
+    done
+fi
+
+for dir in "${pkgconfdir}/conf.d" \
+           "${pkgconfdir}/system-connections" \
+           "${pkgconfdir}/dispatcher.d/no-wait.d" \
+           "${pkgconfdir}/dispatcher.d/pre-down.d" \
+           "${pkgconfdir}/dispatcher.d/pre-up.d" \
+           "${pkgconfdir}/dnsmasq.d" \
+           "${pkgconfdir}/dnsmasq-shared.d" \
+           "${pkgconfdir}/conf.d" \
+           "${pkgconfdir}/VPN" \
+           "${localstatedir}/lib/NetworkManager"; do
+    mkdir -p "${DESTDIR}${dir}"
+done
+
+if [ "$6" = install_docs ]; then
+    mandir=$7
+
+    for alias in nmtui-connect nmtui-edit nmtui-hostname; do
+        ln -f "${DESTDIR}${mandir}/man1/nmtui.1" "${DESTDIR}${mandir}/man1/${alias}.1"
+    done
+
+    ln -f "${DESTDIR}${mandir}/man5/NetworkManager.conf.5" "${DESTDIR}${mandir}/man5/nm-system-settings.conf"
+fi
+