From 7a2a83887bd13d60b6c04d5dc19a419fe8927d0b Mon Sep 17 00:00:00 2001
From: Donald Buczek <buczek@molgen.mpg.de>
Date: Tue, 29 Oct 2019 16:33:28 +0100
Subject: [PATCH] Make install dir for unit files configurable

Currently the systemd service unit files are installed
into /lib/systemd/system if that directory exists. This
might not be optimal for every user, e.g. when the build
system is not the target system or when building as an
unprivileged user using CMAKE_INSTALL_PREFIX.

Make this configurable by adding a cached cmake variable
CMAKE_INSTALL_SYSTEMD_UNITDIR. Usage:

- install unit files into /lib/systemd/system if it exists (old
behavior)

    cmake

- don't install unit files

   cmake -D CMAKE_INSTALL_SYSTEMD_UNITDIR=

- install into absolute path

   cmake -D CMAKE_INSTALL_SYSTEMD_UNITDIR=/path

- install into path relative to ${CMAKE_INSTALL_PREFIX}

   cmake -D CMAKE_INSTALL_SYSTEMD_UNITDIR=path
---
 CMakeLists.txt               | 3 +++
 src/vpnbridge/CMakeLists.txt | 4 ++--
 src/vpnclient/CMakeLists.txt | 4 ++--
 src/vpnserver/CMakeLists.txt | 4 ++--
 4 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2ce66a3b..641945e2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -41,6 +41,9 @@ if(UNIX)
 
   include(CheckIncludeFile)
   Check_Include_File(sys/auxv.h HAVE_SYS_AUXV)
+  if(EXISTS "/lib/systemd/system")
+    set(CMAKE_INSTALL_SYSTEMD_UNITDIR "/lib/systemd" CACHE STRING "Where to install systemd unit files")
+  endif()
 endif()
 
 configure_file("${TOP_DIRECTORY}/AUTHORS.TXT" "${TOP_DIRECTORY}/src/bin/hamcore/authors.txt" COPYONLY)
diff --git a/src/vpnbridge/CMakeLists.txt b/src/vpnbridge/CMakeLists.txt
index fb076876..534d473a 100644
--- a/src/vpnbridge/CMakeLists.txt
+++ b/src/vpnbridge/CMakeLists.txt
@@ -40,11 +40,11 @@ if(UNIX)
   )
 
   install_wrapper_script("vpnbridge" "${CMAKE_INSTALL_FULL_LIBEXECDIR}/softether/vpnbridge/vpnbridge")
-  if(EXISTS "/lib/systemd/system")
+  if (NOT CMAKE_INSTALL_SYSTEMD_UNITDIR STREQUAL "")
     configure_file(${TOP_DIRECTORY}/systemd/softether-vpnbridge.service ${CMAKE_BINARY_DIR}/systemd/softether-vpnbridge.service)
     install(FILES ${CMAKE_BINARY_DIR}/systemd/softether-vpnbridge.service
       COMPONENT "vpnbridge"
-      DESTINATION "/lib/systemd/system"
+      DESTINATION ${CMAKE_INSTALL_SYSTEMD_UNITDIR}
       PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
     )
   endif()
diff --git a/src/vpnclient/CMakeLists.txt b/src/vpnclient/CMakeLists.txt
index 9df369ec..dad4a7e5 100644
--- a/src/vpnclient/CMakeLists.txt
+++ b/src/vpnclient/CMakeLists.txt
@@ -40,11 +40,11 @@ if(UNIX)
   )
 
   install_wrapper_script("vpnclient" "${CMAKE_INSTALL_FULL_LIBEXECDIR}/softether/vpnclient/vpnclient")
-  if(EXISTS "/lib/systemd/system")
+  if (NOT CMAKE_INSTALL_SYSTEMD_UNITDIR STREQUAL "")
     configure_file(${TOP_DIRECTORY}/systemd/softether-vpnclient.service ${CMAKE_BINARY_DIR}/systemd/softether-vpnclient.service)
     install(FILES ${CMAKE_BINARY_DIR}/systemd/softether-vpnclient.service
       COMPONENT "vpnclient"
-      DESTINATION "/lib/systemd/system"
+      DESTINATION ${CMAKE_INSTALL_SYSTEMD_UNITDIR}
       PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
     )
   endif()
diff --git a/src/vpnserver/CMakeLists.txt b/src/vpnserver/CMakeLists.txt
index 26142ee4..c7cf162f 100644
--- a/src/vpnserver/CMakeLists.txt
+++ b/src/vpnserver/CMakeLists.txt
@@ -40,11 +40,11 @@ if(UNIX)
   )
 
   install_wrapper_script("vpnserver" "${CMAKE_INSTALL_FULL_LIBEXECDIR}/softether/vpnserver/vpnserver")
-  if(EXISTS "/lib/systemd/system")
+  if (NOT CMAKE_INSTALL_SYSTEMD_UNITDIR STREQUAL "")
     configure_file(${TOP_DIRECTORY}/systemd/softether-vpnserver.service ${CMAKE_BINARY_DIR}/systemd/softether-vpnserver.service)
     install(FILES ${CMAKE_BINARY_DIR}/systemd/softether-vpnserver.service
       COMPONENT "vpnserver"
-      DESTINATION "/lib/systemd/system"
+      DESTINATION ${CMAKE_INSTALL_SYSTEMD_UNITDIR}
       PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
     )
   endif()