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.

Makefile.am

@@ -5040,7 +5040,6 @@ EXTRA_DIST += \
 	valgrind.suppressions \
 	meson.build \
 	meson_options.txt \
-	meson_post_install.py \
 	config.h.meson \
 	config-extra.h.meson \
 	docs/meson.build \
@@ -5081,6 +5080,7 @@ 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

@@ -895,7 +895,7 @@ 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
+