add systemd support

This adds basic systemd support, incl. socket activation.
If systemd build is disabled, there won't be any sign of it neither
during build nor after.
If systemd build is enabled (default), but systemd is not available,
no systemd stuff is installed, so there is no impact whatsoever.

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 01b43c08ff9a37c65d22bf637e34c56859d7c038..22027ec3b9b6f1822e7dcce8455ad002bacbc923 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -5,6 +5,7 @@ ADD_DEFINITIONS(-Os -Wall -Werror --std=gnu99 -g3 -Wmissing-declarations)
 
 OPTION(BUILD_LUA "build Lua plugin" ON)
 OPTION(BUILD_EXAMPLES "build examples" ON)
+OPTION(ENABLE_SYSTEMD "systemd support" ON)
 
 SET(CMAKE_SHARED_LIBRARY_LINK_C_FLAGS "")
 SET(UBUS_UNIX_SOCKET "/var/run/ubus.sock")
@@ -38,3 +39,15 @@ INSTALL(TARGETS ubusd
 )
 
 INSTALL(FILES ubusmsg.h ubus_common.h libubus.h DESTINATION include)
+
+# FIXME: this works but certainly can be done better:
+SET(UBUSD_BINARY "${CMAKE_INSTALL_PREFIX}/sbin/ubusd")
+
+# do this after the installs so we have the proper paths
+IF(ENABLE_SYSTEMD)
+  INCLUDE(FindPkgConfig)
+  PKG_CHECK_MODULES(SYSTEMD systemd)
+  IF(SYSTEMD_FOUND)
+    ADD_SUBDIRECTORY(systemd)
+  ENDIF()
+ENDIF()

diff --git a/systemd/CMakeLists.txt b/systemd/CMakeLists.txt
new file mode 100644 (file)
index 0000000..54b754b
--- /dev/null
+++ b/systemd/CMakeLists.txt
@@ -0,0 +1,7 @@
+CONFIGURE_FILE(ubus.socket.in ubus.socket)
+CONFIGURE_FILE(ubus.service.in ubus.service)
+
+# Cmakes pkgconfig support is very limited, so for now just hardcode
+SET(SYSTEMD_SYSUNIT_DIR "${SYSTEMD_PREFIX}/lib/systemd/system")
+INSTALL(FILES ${CMAKE_BINARY_DIR}/systemd/ubus.socket ${CMAKE_BINARY_DIR}/systemd/ubus.service
+       DESTINATION ${SYSTEMD_SYSUNIT_DIR})

diff --git a/systemd/ubus.service.in b/systemd/ubus.service.in
new file mode 100644 (file)
index 0000000..185a42f
--- /dev/null
+++ b/systemd/ubus.service.in
@@ -0,0 +1,6 @@
+[Unit]
+Description=OpenWrt micro bus
+Requires=ubus.socket
+
+[Service]
+ExecStart=@UBUSD_BINARY@

diff --git a/systemd/ubus.socket.in b/systemd/ubus.socket.in
new file mode 100644 (file)
index 0000000..364beb7
--- /dev/null
+++ b/systemd/ubus.socket.in
@@ -0,0 +1,8 @@
+[Unit]
+Description=OpenWrt micro bus socket
+
+[Socket]
+ListenStream=@UBUS_UNIX_SOCKET@
+
+[Install]
+WantedBy=sockets.target