README.md: document s6-rc controller

README.md

@@ -8,4 +8,30 @@ dependencies must be taken care of explicitly in other ways.
 This is also a starting point to explore the feasibility of a runit/s6
 controller.
 
+## dbus-controller-s6rc
+
+Build with `meson -Ds6-rc=enabled build`
+
+Usage: `dbus-controller-s6rc -h`
+
+The [s6-rc] controller looks in a s6-rc livedir for services containing the
+file `data/dbus-activatable-name` with a dbus activatable name provided by the
+service. It issues `s6-rc change <service>` when it receives an activation
+request.
+
+Such dbus activatable services can be autogenerated by `tools/s6rc-generator`,
+which generates a s6-rc source database called `dbus` that can be included in
+the list of your databases to compile with `s6-rc-compile`.
+
+It is typically invoked as:
+```
+./s6rc-generator /usr/share/dbus-1/system-services/*
+./s6rc-generator /usr/share/dbus-1/services/*
+```
+for the system and session bus, respectively.
+
+You are free to further tweak this source database as you like, for example
+removing unwanted activatable services.
+
 [dbus-broker]: https://github.com/bus1/dbus-broker
+[s6-rc]: https://skarnet.org/software/s6-rc

meson.build

@@ -27,11 +27,11 @@ add_project_arguments('-DHAVE_' + sdbus.name().to_upper() + '=1', language: 'c')
 
 executable('dbus-controller-dummy', ['controller.c', 'dbus.c', 'main.c', 'policy.c', 'syslog.c'], dependencies: [sdbus])
 
-if get_option('s6-rc') == true
+if get_option('s6-rc').enabled()
 tllist = dependency('tllist')
 
 cc = meson.get_compiler('c')
 skalibs = cc.find_library('skarnet')
 
-executable('dbus-controller-s6', ['activation.c', 'controller.c', 'dbus.c', 'main.c', 'policy.c', 'syslog.c'], dependencies: [sdbus, skalibs, tllist], c_args : '-DHAVE_S6=1')
+executable('dbus-controller-s6rc', ['activation.c', 'controller.c', 'dbus.c', 'main.c', 'policy.c', 'syslog.c'], dependencies: [sdbus, skalibs, tllist], c_args : '-DHAVE_S6=1')
 endif

meson_options.txt

@@ -1,2 +1,2 @@
 option('sd-bus-provider', type: 'combo', choices: ['auto', 'libsystemd', 'libelogind', 'basu'], value: 'auto', description: 'Provider of the sd-bus library')
-option('s6-rc', type : 'boolean', value : false)
+option('s6-rc', type: 'feature', value: 'disabled')