Merge lp:~jamesodhunt/upstart/upstream-override-support into lp:upstart

[James Hunt]

Add override file support.

* init/conf.c:
  - conf_reload_path(): Now takes an extra override_path parameter.
  - is_conf_file() / is_conf_file_std() / is_conf_file_override(): New
    functions to determine type of given file path.
  - toggle_conf_name(): New function which convert a conf file
    name to an override name and vice versa.
  - majority of remaining functions updated to handle override
    files.
* init/conf.h: Prototypes.
* init/job_class.c: Whitespace.
* init/man/init.5: Updated to document override file support.
* init/man/init.8: Added reference to control-alt-delete(7) man page.
* init/paths.h: New macros CONF_EXT_OVERRIDE, CONF_EXT_STD,
  IS_CONF_FILE_OVERRIDE and IS_CONF_FILE_STD.
* init/parse_conf.c: Added assertion to remind us forcibly to add
  override-handling code for directories if we ever allow content in
  'init.conf'.
* init/parse_job.c (parse_job): Additional parameter 'update' to
  allow override files to replace existing Job details.
* init/parse_job.h: Updated parse_job() prototype.
* init/test_conf.c
  - New macros TEST_ENSURE_CLEAN_ENV() and
    TEST_FORCE_WATCH_UPDATE().
  - test_override(): New function.
  - test_toggle_conf_name(): New function.
* init/test_parse_job.c:
  - Updated for extra parse_job() parameter.
  - added a test feature to test_parse_job() to exercise new
    parameter to parse_job().
* util/man/initctl.8: Clarified what it means to restart a job.

=== modified file 'ChangeLog'
--- ChangeLog	2011-05-12 20:42:28 +0000
+++ ChangeLog	2011-06-06 15:24:28 +0000
@@ -1,3 +1,222 @@
[phone]  James Hunt  <[e-mail]>
+
+	Add session support. Note that there are no automatically runnable and
+	explicit tests yet. However, see TESTING.sessions.
+	
+	* TESTING.sessions: ASCII (reStructuredText) document explaining
+	  how to run manual tests for session support (for chroots).
+	* dbus/Upstart.conf: Simplified to support allowing users to invoke
+	  all methods (since Upstart now isolates commands by user).
+	* init/Makefile.am: Added session.[ch] files.
+	* init/session.c: New file. Note that session_from_dbus() will disable sessions
+	  (by returning the NULL session) if environment variable "UPSTART_NO_SESSIONS"
+	  is set to any value (used by tests).
+	* init/session.h: New file.
+	* init/parse_job.h: parse_job(): Add session pointer to prototype.
+	* init/parse_job.c:
+	  - parse_job(): Add session parameter.
+	  - Update calls to job_class_new() to pass session pointer.
+	* init/job.c: job_new(): Crucial change to ensure chroot sessions have
+	  a unique D-Bus name (LP:#728531).
+	* init/job_class.c: 
+	  - job_class_new(): Add session parameter and session support.
+	  - job_class_remove(): Add session parameter to prototype.
+	  - job_class_consider(): Only consider jobs from the appropriate session.
+	  - job_class_reconsider(): Only consider jobs from the appropriate session.
+	  - job_class_start(): Disallow out-of-session modification.
+	  - job_class_stop(): Disallow out-of-session modification.
+	  - job_class_restart(): Disallow out-of-session modification.
+	* init/main.c: Add "--no-sessions" command-line option to disable
+	  sessions and revert to traditional behaviour.
+	* init/job_class.h: 
+	  - job_class_new(): Add session pointer to prototype.
+	  - JobClass: Add session member.
+	* init/job_process.c: job_process_spawn():
+	  - Call chroot(2) for chroot sessions.
+	  - Call setuid(2) for user session jobs.
+	* init/job.c:
+	  - job_emit_event(): Set session for event.
+	  - job_start(): Disallow out-of-session modification.
+	  - job_stop(): Disallow out-of-session modification.
+	  - job_restart(): Disallow out-of-session modification.
+	* init/event.h: Event: Add session member.
+	* init/event.c:
+	  - event_new(): initialize session to NULL.
+	  - event_pending_handle_jobs(): Add session handling.
+	  - event_finished(): Set session for failure event.
+	* init/control.c:
+	  - control_get_job_by_name(): Add session handling.
+	  - control_get_all_jobs(): Add session handling.
+	  - control_emit_event(): Add session handling.
+	* init/conf.c:
+	  - conf_source_new(): Initialise session to NULL.
+	  - conf_reload_path(): Pass session to parse_job().
+	  - conf_select_job(): Add session parameter.
+	* init/conf.h:
+	  - ConfSource: Add session member.
+	  - conf_select_job(): Add session parameter to prototype.
+	* All tests updated to set "UPSTART_NO_SESSIONS" (to disable
+	  sessions).
+
[phone]  James Hunt  <[e-mail]>
+
+	* contrib/bash_completion/upstart:
+	  - Made function names more meaningful:
+	  - _upstart_jobs: Now returns a unique list
+	  - _upstart_events (nee _upstart_named_events ) now considers all
+	    "emits" tokens.
+	  - Updates for "check-config" and "show-config".
+	  - Added "--session" option.
+	  - Added "--no-wait" for emit, reload and restart.
+
+	Man page updates.
+	
+	* init/man/init.5:
+	  - Quoted dashes.
+	  - Explain handling of duplicated stanzas.
+	  - "respawn": Document default count and interval.
+	  - "emits": Reference "initctl check-config".
+	  - Added BUGS section.
+	  - Added copyright.
+	* init/man/init.8:
+	  - Quoted dashes.
+	  - See Also: Added control-alt-delete(7).
+	* util/man/initctl.8:
+	  - Quoted dashes.
+	  - "restart": Clarified meaning.
+	  - "list": Explained "stop/waiting" jobs.
+
[phone]  James Hunt  <[e-mail]>
+
+	Add D-Bus session support to initctl.
+	
+	* util/initctl.c:
+	  - Added "--session" command-line option.
+	  - dbus_bus_type_setter(): New function used by option parser to
+	    distinguish system/session D-Bus bus type.
+	  - system_bus variable now replaced by two others: use_dbus (boolean)
+	    and dbus_bus_type.
+	  - upstart_open(): Updated to handle multiple D-Bus bus types.
+	* util/man/initctl.8: Update for "--session" option.
+	* util/tests/test_initctl.c: Updated to make use of use_dbus and
+	  dbus_bus_type rather than system_bus.
+
+	Add "show-config" command to initctl.
+	
+	* util/initctl.c:
+	  - New functions:
+	    - job_class_condition_handler(): Handler function to retrieve job conditions.
+	    - job_class_condition_err_handler(): Handler error function for
+	      job_class_condition_handler().
+	    - job_class_parse_events(): Convert RPN "start on" and "stop on" conditions to
+	      human-readable format.
+	    - job_class_show_emits(): Display events which job emits.
+	    - job_class_show_conditions(): Make D-Bus calls to retrieve "start on" and
+	      "stop on" conditions.
+	    - show_config_action: Handle "show-config" command..
+	* util/initctl.h: New file providing stack-handling functionality for
+	  RPN parsing for "show-config" command.
+	* util/Makefile.am: Added initctl.h to initctl_SOURCES.
+	* util/man/initctl.8: Updated for "show-config" command and associated
+	  options.
+	* util/tests/test_initctl.c:
+	  - New macros START_UPSTART, STOP_UPSTART, RUN_COMMAND, CREATE_FILE and DELETE_FILE.
+	    These are required since due to the introduction of the
+	    "show-config" initctl command, initctl is no longer solely a proxy
+	    to Upstart: it now has some intelligence (it parses the 
+	    "emits", "start on" and "stop on" conditions) and thus must be
+	    tested directly.
+	  - test_show_config(): New function to test "initctl show-config".
+	  - in_chroot(): New function to detect if tests are being run from
+	    within a chroot environment.
+	  - dbus_configured(): New function which performs a basic check to
+	    establish if D-Bus is configured correctly.
+	  - main(): Added call to test_show_config(), conditional on
+	    a non-chroot environment and a working D-Bus system.
+
+	Add "check-config" command to initctl.
+	
+	* util/initctl.c:
+	  - New functions:
+	    - allow_event(): Determine if specified event is erroneous or not.
+	      Handles globbing.
+	    - allow_job(): Determine if specified job is erroneous or not.
+	      Handles variables (such as instance variables).
+	    - check_condition(): High-level function to handle checking start
+	      on/stop on conditions.
+	    - check_config_action: Handler for "check-config" command.
+	    - display_check_errors(): Display errors from expression tree nodes
+	      that are in error.
+	    - eval_expr_tree(): Evaluate expression tree.
+	    - ignored_events_setter(): handler for '--ignore-events' command-line
+	      option for "check-config" command.
+	    - tree_filter(): Used for filtering expression tree nodes.
+	  - show_config_action(): Update for check-config mode.
+	  - job_class_parse_events(): Update for check-config mode.
+	  - job_class_show_emits(): Update for check-config mode.
+	* util/initctl.h:
+	  - Added structs for JobCondition, CheckConfigData and ExprNode.
+	  - New macros: MAKE_EXPR_NODE() and MAKE_JOB_CONDITION().
+	* util/tests/test_initctl.c:
+	  - test_check_config(): New function to test "initctl check-config".
+	  - main(): Added call to test_check_config(), conditional on
+	    a non-chroot environment and a working D-Bus system.
+	* util/man/initctl.8: Updated for "check-config" command and associated
+	  options.
+	* conf/rc-sysinit.conf: Added "emits" stanza, required by
+	"check-config".
+
+	Addition of initctl2dot script for visualisation.
+	
+	* Makefile.am: Added scripts directory.
+	* configure.ac: Updated AC_CONFIG_FILES for scripts/Makefile.
+	* scripts/Makefile.am: Makefile for scripts.
+	* scripts/initctl2dot.py: Python script to produce dot(1) graphs of
+	  "initctl show-config" output.
+	* scripts/man/initctl2dot.8: Man page for initctl2dot.py script.
+
+	Addition of init-checkconf script.
+	
+	* scripts/init-checkconf.sh: Script to determine if specified job
+	  config file is valid or not.
+	* scripts/man/init-checkconf.8: Man page for init-checkconf.sh.
+	* scripts/Makefile.am: Added init-checkconf script and man
+	  page.
+
[phone]  James Hunt  <[e-mail]>
+
+	Add command-line option to use D-Bus session bus (for testing).
+	
+	* init/control.c:
+	  - Added new boolean use_session_bus.
+	  - Updated comments.
+	  - control_handle_bus_type(): New function to allow selection of
+	    session bus via env var "UPSTART_USE_SESSION_BUS".
+	    Also logs use of session bus if use_session_bus set.
+	  - control_bus_open(): Now connects to either D-Bus system bus or session bus.
+	* init/control.h: New define for USE_SESSION_BUS_ENV.
+	* init/main.c: Addition of "--session" command-line option.
+	* init/man/init.8: Update for new "--session" command-line option.
+
+	* Corrected copyright notices.
+
+	Add option to allow alternate location for job config files.
+	
+	* init/main.c:
+	  - Added "--confdir <dir>" command-line option.
+	  - handle_confdir(): New function to select alternate confdir using env
+	    var "UPSTART_CONFDIR" or command-line option (for testing).
+	* init/paths.h: Added define for CONFDIR_ENV.
+	* init/man/init.8: Update for new "--confdir" command-line option.
+
+	Add ability to suppress initial event and/or change its name.
+	
+	* init/main.c: New command-line options: "--no-startup-event" and
+	  "--startup-event". If "--no-startup-event" specified, log message as a
+	  debug aid.
+	* init/man/init.8: Documentation for new command-line options:
+	  "--no-startup-event" and "--startup-event".
+
 2011-05-12  Marc - A. Dahlhaus  <[e-mail]>
 
 	* init/job_class.h (JobClass): Add kill signal member

=== modified file 'Makefile.am'
--- Makefile.am	2010-02-04 03:42:29 +0000
+++ Makefile.am	2011-06-06 15:24:28 +0000
@@ -1,6 +1,6 @@
 ## Process this file with automake to produce Makefile.in
 
-SUBDIRS = intl dbus init util conf doc contrib po
+SUBDIRS = intl dbus init util conf doc contrib po scripts
 
 EXTRA_DIST = HACKING
 

=== added file 'TESTING.sessions'
--- TESTING.sessions	1970-01-01 00:00:00 +0000
+++ TESTING.sessions	2011-06-06 15:24:28 +0000
@@ -0,0 +1,252 @@
+.. contents::
+
+=============================
+Testing Sessions with Upstart
+=============================
+
+Upstart now has support for chroots which are implemented by creating a
+separate session for every user within each chroot. It also has partial
+support for user sessions, but since this is experimental (and disabled
+in Ubuntu), this document does not cover testing this feature.
+
+The session support does not yet provide full tests (as would be run by
+"``make check``"). This is partly due to the complexity of automatically
+testing some of the scenarios below.
+
+This document attempts to outline the minimum set of tests that should
+be performed to ensure that chroot support works as expected.
+
+Assumptions
+===========
+
+You are running an Ubuntu or Debian system.
+
+Setup
+=====
+
+#. Install a chroot environement (such as ``schroot(1)``) and configure it.
+#. run, "``debootstrap(8)``" to install the same release as you are running into your chroot.
+#. Create the following files *outside* your chroot.
+
+   - ``/etc/init/foo.conf``::
+     
+       start on wibble
+       
+       script
+         exec 2>>/tmp/foo.$$.log
+         echo "foo: stat=`stat /`" 
+         echo "foo: env=`env`"
+         sleep 999 
+       end script
+
+   - ``/etc/init/outside_chroot.conf``::
+
+       start on A
+          
+       script
+         exec 2>>/tmp/outside_chroot.$$.log
+         echo "in_chroot: stat=`stat /`" 
+         echo "in_chroot: env=`env`"
+         sleep 999 
+       end script
+
+#. Create following files inside chroot environment.
+
+   - ``/path/to/chroot/etc/init/foo.conf``::
+
+       start on wibble
+          
+       script
+         exec 2>>/tmp/foo.$$.log
+         echo "foo: stat=`stat /`" 
+         echo "foo: env=`env`" 
+         sleep 999
+       end script
+
+   - ``/path/to/chroot/etc/init/in_chroot.conf``::
+
+       start on A
+        
+       script
+         exec 2>>/tmp/in_chroot.$$.log
+         echo "in_chroot: stat=`stat /`" 
+         echo "in_chroot: env=`env`" 
+         sleep 999
+       end script
+
+   
+Run as non-``root`` with no chroot
+==================================
+
+- ``initctl list``
+
+  Ensure list is contents of ``/etc/init/``: the command below should
+  return no output::
+
+    cmp <(initctl list|awk '{print }'|sort -u) <(cd /etc/init && ls *.conf|cut -d: -f2-|sed 's/\.conf//g'|sort -u)
+
+- ``initctl status cron``
+
+  Should work.
+
+- ``initctl show-config cron``
+
+  Should work.
+
+- ``initctl check-config``
+
+  Should work.
+
+- ``start foo``
+
+  Should fail ("``initctl: Rejected send message``").
+
+- ``stop cron``
+
+   Should fail ("``initctl: Rejected send message``").
+
+- ``restart cron``
+
+  Should fail ("``initctl: Rejected send message``").
+
+- ``initctl emit bar``
+
+  Should fail ("``initctl: Rejected send message``").
+
+Run as ``root`` with no chroot
+==============================
+
+- ``initctl list``
+
+  Ensure list is contents of ``/etc/init/``: command below should return no output::
+
+    cmp <(initctl list|awk '{print }'|sort -u) <(cd /etc/init && ls *.conf|cut -d: -f2-|sed 's/\.conf//g'|sort -u)
+
+- ``initctl status outside_chroot``
+
+  Should work.
+
+- ``initctl status in_chroot``
+
+  Should fail with message::
+
+    initct: Unknown job: in_chroot
+
+- ``initctl show-config <job>``
+
+- ``initctl check-config <job>``
+
+- ``start in_chroot``
+
+  Should fail with message::
+
+    initct: Unknown job: in_chroot
+
+- ``start outside_chroot``
+
+   Should work.
+
+- ``stop in_chroot``
+
+   Should fail with message::
+
+    initct: Unknown job: in_chroot
+
+- ``restart outside_chroot``
+
+   Sould work.
+
+- ``stop outside_chroot``
+
+   Should work.
+
+- ``initctl emit wibble``
+
+  - Ensure ``/etc/init/foo.conf`` runs by looking at the log and ensuring
+    the inode for the stat of '``/``' is the same as running "``stat /``" on
+    the command-line.
+
+  * Ensure ``/path/to/chroot/etc/init/foo.conf`` does *NOT* run.
+
+- ``initctl emit A``
+
+  - Ensure ``/etc/init/outside_chroot.conf`` runs.
+
+  - Ensure ``/path/to/chroot/etc/init/in_chroot.conf`` does *NOT* run.
+
+Run as ``root`` inside a chroot
+===============================
+
+- ``initctl list``
+
+  Ensure list is contents of ``/path/to/chroot/etc/init/``: command below should return no output::
+
+    cmp <(initctl list|awk '{print }'|sort -u) <(cd /etc/init && ls *.conf|cut -d: -f2-|sed 's/\.conf//g'|sort -u)
+
+- ``initctl status in_chroot``
+
+  Should work.
+
+- ``initctl status outside_chroot``
+
+  Should fail with message::
+
+    initct: Unknown job: outside_chroot
+
+- ``initctl show-config <job>``
+
+- ``initctl check-config <job>``
+
+- ``start outside_chroot``
+
+   Should fail with message::
+
+    initct: Unknown job: outside_chroot
+
+- ``stop outside_chroot``
+
+   Should fail with message::
+
+    initct: Unknown job: outside_chroot
+
+- ``start in_chroot``
+
+   should work.
+
+- ``restart in_chroot``
+
+   Should work.
+
+- ``stop in_chroot``
+
+   Should work.
+
+- ``initctl emit wibble``
+
+  - Ensure ``/path/to/chroot/etc/init/foo.conf`` runs by looking at the log and ensuring
+    the inode for the stat of '``/``' is the same as running "``stat /``" on the command-line.
+
+  - Ensure ``/etc/init/foo.conf`` does *NOT* run.
+
+- ``initctl emit A``
+
+  - Ensure ``/path/to/chroot/etc/init/in_chroot.conf`` runs.
+
+  - Ensure ``/etc/init/outside_chroot.conf`` does *NOT* run.
+
+Run as non-root inside a chroot
+===============================
+
+Not supported.
+
+Run with ``--no-sessions``
+==========================
+
+The "``--no-sessions``" option makes Upstart behave as it used to prior to
+the introduction of session support.
+
+#. Reboot system and specify "``--no-sessions``" on kernel command-line.
+
+.. Ensure "``initctl list``" within a chroot displays the same list as
+   "``initctl list``" run outside of any chroot environment.
+

=== modified file 'conf/rc-sysinit.conf'
--- conf/rc-sysinit.conf	2010-02-04 03:59:06 +0000
+++ conf/rc-sysinit.conf	2011-06-06 15:24:28 +0000
@@ -13,6 +13,8 @@
 # or by faking an old /etc/inittab entry
 env DEFAULT_RUNLEVEL=2
 
+emits runlevel
+
 # There can be no previous runlevel here, but there might be old
 # information in /var/run/utmp that we pick up, and we don't want
 # that.

=== modified file 'configure.ac'
--- configure.ac	2011-03-22 17:53:17 +0000
+++ configure.ac	2011-06-06 15:24:28 +0000
@@ -2,7 +2,7 @@
 
 AC_PREREQ(2.61)
 AC_INIT([upstart], [1.3], [[e-mail]])
-NIH_COPYRIGHT([[Copyright © 2011 Scott James Remnant, Google Inc., Canonical Ltd.]])
+NIH_COPYRIGHT([[Copyright © 2011 Scott James Remnant, Canonical Ltd.]])
 AC_CONFIG_SRCDIR([init/main.c])
 AC_CONFIG_MACRO_DIR([m4])
 
@@ -64,6 +64,7 @@
 
 AC_CONFIG_FILES([ Makefile intl/Makefile
 		  dbus/Makefile init/Makefile util/Makefile conf/Makefile
-		  doc/Makefile contrib/Makefile po/Makefile.in ])
+		  doc/Makefile contrib/Makefile po/Makefile.in
+		  scripts/Makefile ])
 AC_CONFIG_HEADERS([config.h])
 AC_OUTPUT

=== modified file 'contrib/bash_completion/upstart'
--- contrib/bash_completion/upstart	2010-12-21 13:54:49 +0000
+++ contrib/bash_completion/upstart	2011-06-06 15:24:28 +0000
@@ -3,26 +3,28 @@
 #
 # We don't provide completion for 'init' itself for obvious reasons.
 have initctl &&
-_upstart_conf_events()
-{
-  initctl list|awk '{print $1}'
-} &&
-_upstart_named_events()
-{
-  (cd /etc/init && grep '^emits ' *.conf|sed 's/^emits //g')
-} &&
-_upstart_events()
-{
-  (_upstart_conf_events;_upstart_named_events)|tr ' ' '\n'|sort -u
-} &&
-_upstart_startable_events()
+_upstart_jobs()
+{
+  initctl list|awk '{print $1}'|sort -u
+} &&
+_upstart_startable_jobs()
 {
   initctl list|cut -d\, -f1|awk '$2 == "stop/waiting" {print $1}'
 } &&
-_upstart_stoppable_events()
+_upstart_stoppable_jobs()
 {
   initctl list|cut -d\, -f1|awk '$2 == "start/running" {print $1}'
 } &&
+_upstart_events()
+{
+  # note that we don't provide the internal events such as "starting"
+  # (and those from mountall) since the user should be using the
+  # associated command to emit such events.
+  (cd /etc/init && \
+   egrep '^[[:space:]]*emits ' *.conf |\
+   cut -d: -f2- | sed 's/^[[:space:]]*emits //g' |\
+   tr ' ' '\n' | awk '{print $NF}' | grep -v ^$|sort -u)
+} &&
 _upstart_initctl()
 {
   _get_comp_words_by_ref cur prev
@@ -32,34 +34,92 @@
   case "$prev" in
 
     start)
-      COMPREPLY=( $(compgen -W "-n --no-wait $(_upstart_startable_events)" -- ${cur}) )
+      COMPREPLY=( $(compgen -W "-n --no-wait $(_upstart_startable_jobs)" -- ${cur}) )
       return 0
     ;;
 
     stop)
-      COMPREPLY=( $(compgen -W "-n --no-wait $(_upstart_stoppable_events)" -- ${cur}) )
+      COMPREPLY=( $(compgen -W "-n --no-wait $(_upstart_stoppable_jobs)" -- ${cur}) )
       return 0
     ;;
 
     emit)
-      COMPREPLY=( $(compgen -W "$(_upstart_events)" -- ${cur}) )
-      return 0
-    ;;
-
-    reload|restart|status)
-      COMPREPLY=( $(compgen -W "$(_upstart_conf_events)" -- ${cur}) )
+      COMPREPLY=( $(compgen -W "-n --no-wait $(_upstart_events)" -- ${cur}) )
+      return 0
+    ;;
+
+    -i|--ignore-events)
+      # handle visualisation options after check-config command
+      for cmd in check-config
+      do
+        cwords=${COMP_WORDS[@]##}
+        filtered_cwords=${COMP_WORDS[@]##${cmd}}
+        if [ "$filtered_cwords" != "$cwords" ]
+        then
+          COMPREPLY=( $(compgen -W "$(_upstart_jobs)" -- ${cur}) )
+          return 0
+        fi
+      done
+    ;;
+
+    -e|--enumerate)
+      # handle visualisation options after show-config command
+      for cmd in show-config
+      do
+        cwords=${COMP_WORDS[@]##}
+        filtered_cwords=${COMP_WORDS[@]##${cmd}}
+        if [ "$filtered_cwords" != "$cwords" ]
+        then
+          COMPREPLY=( $(compgen -W "$(_upstart_jobs)" -- ${cur}) )
+          return 0
+        fi
+      done
+    ;;
+
+    reload|restart)
+      COMPREPLY=( $(compgen -W "-n --no-wait $(_upstart_stoppable_jobs)" -- ${cur}) )
+      return 0
+    ;;
+
+    status)
+      COMPREPLY=( $(compgen -W "$(_upstart_jobs)" -- ${cur}) )
+      return 0
+    ;;
+
+    check-config)
+      COMPREPLY=( $(compgen -W "-w --warn -i --ignore-events= $(_upstart_jobs)" -- ${cur}) )
+      return 0
+    ;;
+    show-config)
+      COMPREPLY=( $(compgen -W "-e --enumerate $(_upstart_jobs)" -- ${cur}) )
       return 0
     ;;
 
     -n|--no-wait)
-      # allow no wait after start/stop commands
-      for cmd in start stop
+      # allow 'no wait' for certain commands
+      for cmd in start stop restart emit
       do
         cwords=${COMP_WORDS[@]##}
         filtered_cwords=${COMP_WORDS[@]##${cmd}}
         if [ "$filtered_cwords" != "$cwords" ]
         then
-          COMPREPLY=( $(compgen -W "$(_upstart_${cmd}able_events)" -- ${cur}) )
+          case "$cmd" in
+            start)
+              COMPREPLY=( $(compgen -W "$(_upstart_startable_jobs)" -- ${cur}) )
+            ;;
+
+            stop)
+              COMPREPLY=( $(compgen -W "$(_upstart_stoppable_jobs)" -- ${cur}) )
+            ;;
+
+            restart)
+              COMPREPLY=( $(compgen -W "$(_upstart_stoppable_jobs)" -- ${cur}) )
+            ;;
+
+            emit)
+              COMPREPLY=( $(compgen -W "$(_upstart_events)" -- ${cur}) )
+            ;;
+          esac
           return 0
         fi
       done
@@ -71,7 +131,7 @@
     ;;
   esac
 
-  opts="--help --version -q --quiet -v --verbose --system --dest="
+  opts="--help --version -q --quiet -v --verbose --session --system --dest="
   cmds=$(initctl help|grep "^  [^ ]"|awk '{print $1}')
 
   COMPREPLY=( $(compgen -W "${opts} ${cmds}" -- ${cur}) )
@@ -84,7 +144,7 @@
   COMPREPLY=()
   _get_comp_words_by_ref cur prev
 
-  opts="--help --version -q --quiet -v --verbose --system --dest= \
+  opts="--help --version -q --quiet -v --verbose --session --system --dest= \
         -n --no-wait"
 
   case "$prev" in
@@ -94,7 +154,7 @@
     ;;
   esac
 
-  COMPREPLY=( $(compgen -W "$opts $(_upstart_startable_events)" -- ${cur}) )
+  COMPREPLY=( $(compgen -W "$opts $(_upstart_startable_jobs)" -- ${cur}) )
   return 0
 } && complete -F _upstart_start start
 
@@ -104,7 +164,7 @@
   COMPREPLY=()
   _get_comp_words_by_ref cur prev
 
-  opts="--help --version -q --quiet -v --verbose --system --dest= \
+  opts="--help --version -q --quiet -v --verbose --session --system --dest= \
         -n --no-wait"
 
   case "$prev" in
@@ -114,7 +174,7 @@
     ;;
   esac
 
-  COMPREPLY=( $(compgen -W "$opts $(_upstart_stoppable_events)" -- ${cur}) )
+  COMPREPLY=( $(compgen -W "$opts $(_upstart_stoppable_jobs)" -- ${cur}) )
   return 0
 } && complete -F _upstart_stop stop
 
@@ -124,7 +184,7 @@
   COMPREPLY=()
   _get_comp_words_by_ref cur prev
 
-  opts="--help --version -q --quiet -v --verbose --system --dest= \
+  opts="--help --version -q --quiet -v --verbose --session --system --dest= \
         -n --no-wait"
 
   case "$prev" in
@@ -134,7 +194,7 @@
     ;;
   esac
 
-  COMPREPLY=( $(compgen -W "$opts $(_upstart_events)" -- ${cur}) )
+  COMPREPLY=( $(compgen -W "$opts $(_upstart_stoppable_jobs)" -- ${cur}) )
   return 0
 
 } && complete -F _upstart_restart restart
@@ -145,7 +205,7 @@
   COMPREPLY=()
   _get_comp_words_by_ref cur prev
 
-  opts="--help --version -q --quiet -v --verbose --system --dest="
+  opts="--help --version -q -d --detail -e --enumerate --quiet -v --verbose --session --system --dest="
 
   case "$prev" in
     --help|--version)
@@ -154,7 +214,7 @@
     ;;
   esac
 
-  COMPREPLY=( $(compgen -W "$opts $(_upstart_events)" -- ${cur}) )
+  COMPREPLY=( $(compgen -W "$opts $(_upstart_jobs)" -- ${cur}) )
   return 0
 
 } && complete -F _upstart_status status
@@ -165,7 +225,7 @@
   COMPREPLY=()
   _get_comp_words_by_ref cur prev
 
-  opts="--help --version -q --quiet -v --verbose --system --dest="
+  opts="--help --version -q --quiet -v --verbose --session --system --dest="
 
   case "$prev" in
     --help|--version)
@@ -174,7 +234,7 @@
     ;;
   esac
 
-  COMPREPLY=( $(compgen -W "$opts $(_upstart_events)" -- ${cur}) )
+  COMPREPLY=( $(compgen -W "$opts $(_upstart_stoppable_jobs)" -- ${cur}) )
   return 0
 
 } && complete -F _upstart_reload reload

=== modified file 'dbus/Upstart.conf'
--- dbus/Upstart.conf	2009-07-02 17:46:41 +0000
+++ dbus/Upstart.conf	2011-06-06 15:24:28 +0000
@@ -9,12 +9,14 @@
     <allow own="com.ubuntu.Upstart" />
   </policy>
 
-  <!-- Permit the root user to invoke all of the methods on Upstart, its jobs
-       or their instances, and to get and set properties. -->
-  <policy user="root">
+  <!-- Allow any user to invoke all of the methods on Upstart, its jobs
+       or their instances, and to get and set properties - since Upstart
+       isolates commands by user. -->
+  <policy context="default">
+    <allow send_destination="com.ubuntu.Upstart"
+	   send_interface="org.freedesktop.DBus.Introspectable" />
     <allow send_destination="com.ubuntu.Upstart"
 	   send_interface="org.freedesktop.DBus.Properties" />
-
     <allow send_destination="com.ubuntu.Upstart"
 	   send_interface="com.ubuntu.Upstart0_6" />
     <allow send_destination="com.ubuntu.Upstart"
@@ -22,36 +24,4 @@
     <allow send_destination="com.ubuntu.Upstart"
 	   send_interface="com.ubuntu.Upstart0_6.Instance" />
   </policy>
-
-  <!-- Allow any user to introspect Upstart's interfaces, to obtain the
-       values of properties (but not set them) and to invoke selected
-       methods on Upstart and its jobs that are used to walk information. -->
-  <policy context="default">
-    <allow send_destination="com.ubuntu.Upstart"
-	   send_interface="org.freedesktop.DBus.Introspectable" />
-
-    <allow send_destination="com.ubuntu.Upstart"
-	   send_interface="org.freedesktop.DBus.Properties"
-	   send_type="method_call" send_member="Get" />
-    <allow send_destination="com.ubuntu.Upstart"
-	   send_interface="org.freedesktop.DBus.Properties"
-	   send_type="method_call" send_member="GetAll" />
-
-    <allow send_destination="com.ubuntu.Upstart"
-	   send_interface="com.ubuntu.Upstart0_6"
-	   send_type="method_call" send_member="GetJobByName" />
-    <allow send_destination="com.ubuntu.Upstart"
-	   send_interface="com.ubuntu.Upstart0_6"
-	   send_type="method_call" send_member="GetAllJobs" />
-
-    <allow send_destination="com.ubuntu.Upstart"
-	   send_interface="com.ubuntu.Upstart0_6.Job"
-	   send_type="method_call" send_member="GetInstance" />
-    <allow send_destination="com.ubuntu.Upstart"
-	   send_interface="com.ubuntu.Upstart0_6.Job"
-	   send_type="method_call" send_member="GetInstanceByName" />
-    <allow send_destination="com.ubuntu.Upstart"
-	   send_interface="com.ubuntu.Upstart0_6.Job"
-	   send_type="method_call" send_member="GetAllInstances" />
-  </policy>
 </busconfig>

=== modified file 'dbus/upstart.h'
--- dbus/upstart.h	2010-12-10 04:04:51 +0000
+++ dbus/upstart.h	2011-06-06 15:24:28 +0000
@@ -31,7 +31,7 @@
 #  define DBUS_SERVICE_UPSTART "com.ubuntu.TestUpstart"
 # else
 #  define DBUS_SERVICE_UPSTART "com.ubuntu.Upstart"
-#endif
+# endif
 #endif
 
 

=== modified file 'init/Makefile.am'
--- init/Makefile.am	2010-02-04 03:42:29 +0000
+++ init/Makefile.am	2011-06-06 15:24:28 +0000
@@ -40,6 +40,7 @@
 	system.c system.h \
 	environ.c environ.h \
 	process.c process.h \
+	session.c session.h \
 	job_class.c job_class.h \
 	job_process.c job_process.h \
 	job.c job.h \
@@ -158,6 +159,7 @@
 	system.o environ.o process.o \
 	job_class.o job_process.o job.o event.o event_operator.o blocked.o \
 	parse_job.o parse_conf.o conf.o control.o \
+	session.o \
 	com.ubuntu.Upstart.o \
 	com.ubuntu.Upstart.Job.o com.ubuntu.Upstart.Instance.o \
 	$(NIH_LIBS) \
@@ -169,6 +171,7 @@
 	system.o environ.o process.o \
 	job_class.o job_process.o job.o event.o event_operator.o blocked.o \
 	parse_job.o parse_conf.o conf.o control.o \
+	session.o \
 	com.ubuntu.Upstart.o \
 	com.ubuntu.Upstart.Job.o com.ubuntu.Upstart.Instance.o \
 	$(NIH_LIBS) \
@@ -180,6 +183,7 @@
 	system.o environ.o process.o \
 	job_class.o job_process.o job.o event.o event_operator.o blocked.o \
 	parse_job.o parse_conf.o conf.o control.o \
+	session.o \
 	com.ubuntu.Upstart.o \
 	com.ubuntu.Upstart.Job.o com.ubuntu.Upstart.Instance.o \
 	$(NIH_LIBS) \
@@ -191,6 +195,7 @@
 	system.o environ.o process.o \
 	job_class.o job_process.o job.o event.o event_operator.o blocked.o \
 	parse_job.o parse_conf.o conf.o control.o \
+	session.o \
 	com.ubuntu.Upstart.o \
 	com.ubuntu.Upstart.Job.o com.ubuntu.Upstart.Instance.o \
 	$(NIH_LIBS) \
@@ -202,6 +207,7 @@
 	system.o environ.o process.o \
 	job_class.o job_process.o job.o event.o event_operator.o blocked.o \
 	parse_job.o parse_conf.o conf.o control.o \
+	session.o \
 	com.ubuntu.Upstart.o \
 	com.ubuntu.Upstart.Job.o com.ubuntu.Upstart.Instance.o \
 	$(NIH_LIBS) \
@@ -213,6 +219,7 @@
 	system.o environ.o process.o \
 	job_class.o job_process.o job.o event.o event_operator.o blocked.o \
 	parse_job.o parse_conf.o conf.o control.o \
+	session.o \
 	com.ubuntu.Upstart.o \
 	com.ubuntu.Upstart.Job.o com.ubuntu.Upstart.Instance.o \
 	$(NIH_LIBS) \
@@ -224,6 +231,7 @@
 	system.o environ.o process.o \
 	job_class.o job_process.o job.o event.o event_operator.o blocked.o \
 	parse_job.o parse_conf.o conf.o control.o \
+	session.o \
 	com.ubuntu.Upstart.o \
 	com.ubuntu.Upstart.Job.o com.ubuntu.Upstart.Instance.o \
 	$(NIH_LIBS) \
@@ -235,6 +243,7 @@
 	system.o environ.o process.o \
 	job_class.o job_process.o job.o event.o event_operator.o blocked.o \
 	parse_job.o parse_conf.o conf.o control.o \
+	session.o \
 	com.ubuntu.Upstart.o \
 	com.ubuntu.Upstart.Job.o com.ubuntu.Upstart.Instance.o \
 	$(NIH_LIBS) \
@@ -246,6 +255,7 @@
 	system.o environ.o process.o \
 	job_class.o job_process.o job.o event.o event_operator.o blocked.o \
 	parse_job.o parse_conf.o conf.o control.o \
+	session.o \
 	com.ubuntu.Upstart.o \
 	com.ubuntu.Upstart.Job.o com.ubuntu.Upstart.Instance.o \
 	$(NIH_LIBS) \
@@ -257,6 +267,7 @@
 	system.o environ.o process.o \
 	job_class.o job_process.o job.o event.o event_operator.o blocked.o \
 	parse_job.o parse_conf.o conf.o control.o \
+	session.o \
 	com.ubuntu.Upstart.o \
 	com.ubuntu.Upstart.Job.o com.ubuntu.Upstart.Instance.o \
 	$(NIH_LIBS) \
@@ -268,6 +279,7 @@
 	system.o environ.o process.o \
 	job_class.o job_process.o job.o event.o event_operator.o blocked.o \
 	parse_job.o parse_conf.o conf.o control.o \
+	session.o \
 	com.ubuntu.Upstart.o \
 	com.ubuntu.Upstart.Job.o com.ubuntu.Upstart.Instance.o \
 	$(NIH_LIBS) \

=== modified file 'init/conf.c'
--- init/conf.c	2011-03-15 18:44:09 +0000
+++ init/conf.c	2011-06-06 15:24:28 +0000
@@ -2,8 +2,7 @@
  *
  * conf.c - configuration management
  *
- * Copyright © 2011 Google Inc.
- * Copyright © 2009 Canonical Ltd.
+ * Copyright © 2009,2010,2011 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -49,7 +48,7 @@
 #include "parse_conf.h"
 #include "conf.h"
 #include "errors.h"
-
+#include "paths.h"
 
 /* Prototypes for static functions */
 static int  conf_source_reload_file    (ConfSource *source)
@@ -71,9 +70,19 @@
 					struct stat *statbuf)
 	__attribute__ ((warn_unused_result));
 
-static int  conf_reload_path           (ConfSource *source, const char *path)
-	__attribute__ ((warn_unused_result));
-
+static int  conf_reload_path           (ConfSource *source, const char *path,
+					const char *override_path)
+	__attribute__ ((warn_unused_result));
+
+static inline int  is_conf_file        (const char *path)
+	__attribute__ ((warn_unused_result));
+
+static inline int is_conf_file_std     (const char *path)
+	__attribute__ ((warn_unused_result));
+
+static inline int
+is_conf_file_override                  (const char *path)
+	__attribute__ ((warn_unused_result));
 
 /**
  * conf_sources:
@@ -86,6 +95,115 @@
 
 
 /**
+ * is_conf_file_std:
+ * @path: path to check.
+ *
+ * Determine if specified path contains a legitimate
+ * configuration file name.
+ *
+ * Returns: TRUE if @path contains a valid configuration file name,
+ * else FALSE.
+ *
+ **/
+static inline int
+is_conf_file_std (const char *path)
+{
+	char *ptr = strrchr (path, '.');
+
+	if (ptr && IS_CONF_EXT_STD (ptr))
+		return TRUE;
+
+	return FALSE;
+}
+
+/**
+ * is_conf_file_override:
+ * @path: path to check.
+ *
+ * Determine if specified path contains a legitimate
+ * override file name.
+ *
+ * Returns: TRUE if @path contains a valid override file name,
+ * else FALSE.
+ *
+ **/
+static inline int
+is_conf_file_override (const char *path)
+{
+	char *ptr = strrchr (path, '.');
+
+	if (ptr && IS_CONF_EXT_OVERRIDE (ptr))
+		return TRUE;
+
+	return FALSE;
+}
+
+/**
+ * is_conf_file:
+ * @path: path to check.
+ *
+ * Determine if specified path contains a legitimate
+ * configuration file or override file name.
+ *
+ * Returns: TRUE if @path contains a valid configuration
+ * file or override file name, else FALSE.
+ *
+ **/
+static inline int
+is_conf_file (const char *path)
+{
+	char *ptr = strrchr (path, '.');
+
+	if (ptr && (ptr > path) && (ptr[-1] != '/') && IS_CONF_EXT (ptr))
+		return TRUE;
+
+	return FALSE;
+}
+
+/**
+ * Convert a configuration file name to an override file name and vice
+ * versa.
+ *
+ * For example, if @path is "foo.conf", this function will return
+ * "foo.override", whereas if @path is "foo.override", it will return
+ * "foo.conf".
+ *
+ * Note that this function should be static, but isn't to allow the
+ * tests to access it.
+ *
+ * @parent: parent of returned path,
+ * @path: path to a configuration file.
+ *
+ * Returns: newly allocated toggled path, or NULL on error.
+ **/
+char *
+toggle_conf_name (const void     *parent,
+		 const char     *path)
+{
+	char *new_path;
+	char *ext;
+	char *new_ext;
+	size_t len;
+
+	ext = strrchr (path, '.');
+	if (!ext)
+		return NULL;
+
+	new_ext = IS_CONF_EXT_STD (ext)
+		? CONF_EXT_OVERRIDE
+		: CONF_EXT_STD;
+
+	len = strlen (new_ext);
+
+	new_path = NIH_MUST (nih_strndup (parent, path, (ext - path) + len));
+
+	memcpy (new_path + (ext - path), new_ext, len);
+
+	return new_path;
+}
+
+
+/**
  * conf_init:
  *
  * Initialise the conf_sources list.
@@ -147,6 +265,7 @@
 
 	source->type = type;
 	source->watch = NULL;
+	source->session = NULL;
 
 	source->flag = FALSE;
 	source->files = nih_hash_string_new (source, 0);
@@ -235,8 +354,8 @@
 			err = nih_error_get ();
 			if (err->number != ENOENT)
 				nih_error ("%s: %s: %s", source->path,
-					   _("Unable to load configuration"),
-					   err->message);
+					_("Unable to load configuration"),
+					err->message);
 			nih_free (err);
 		}
 	}
@@ -329,10 +448,16 @@
 conf_source_reload_file (ConfSource *source)
 {
 	NihError *err = NULL;
+	nih_local char *override_path = NULL;
+
+	struct stat statbuf;
 
 	nih_assert (source != NULL);
 	nih_assert (source->type == CONF_FILE);
 
+	/* this function should only be called for standard
+	 * configuration files.
+	 */
 	if (! source->watch) {
 		nih_local char *dpath = NULL;
 		char           *dname;
@@ -361,7 +486,7 @@
 	/* Parse the file itself.  If this fails, then we can discard the
 	 * inotify error, since this one will be better.
 	 */
-	if (conf_reload_path (source, source->path) < 0) {
+	if (conf_reload_path (source, source->path, NULL) < 0) {
 		if (err)
 			nih_free (err);
 
@@ -382,6 +507,23 @@
 		nih_free (err);
 	}
 
+	if (! is_conf_file_std (source->path))
+		return 0;
+
+	override_path = toggle_conf_name (NULL, source->path);
+
+	if (stat (override_path, &statbuf) != 0)
+		return 0;
+
+	nih_debug ("Updating configuration for %s from %s",
+		  source->path, override_path);
+	if (conf_reload_path (source, source->path, override_path) < 0) {
+		if (err)
+			nih_free (err);
+
+		return -1;
+	}
+
 	return 0;
 }
 
@@ -501,19 +643,18 @@
  * @is_dir: TRUE of @path is a directory.
  *
  * This is the file filter used for the jobs directory, we only care
- * about paths with the ".conf" extension.  Directories that
- * match the nih_file_ignore() function are also ignored.
- *
- * Returns: FALSE if @path ends in ".conf", or is the original source,
- * TRUE otherwise.
+ * about paths with particular extensions (see IS_CONF_EXT).
+ *
+ * Directories that match the nih_file_ignore() function are also ignored.
+ *
+ * Returns: FALSE if @path ends in ".conf" or ".override",
+ * or is the original source, TRUE otherwise.
  **/
 static int
 conf_dir_filter (ConfSource *source,
 		 const char *path,
 		 int         is_dir)
 {
-	char *ptr;
-
 	nih_assert (source != NULL);
 	nih_assert (path != NULL);
 
@@ -523,8 +664,7 @@
 	if (is_dir)
 		return nih_file_ignore (NULL, path);
 
-	ptr = strrchr (path, '.');
-	if (ptr && (ptr > path) && (ptr[-1] != '/') && (! strcmp (ptr, ".conf")))
+	if (is_conf_file (path))
 		return FALSE;
 
 	return TRUE;
@@ -546,29 +686,92 @@
  * After checking that it was a regular file that was changed, we reload it;
  * we expect this to fail sometimes since the file may be only partially
  * written.
-  **/
+ **/
 static void
 conf_create_modify_handler (ConfSource  *source,
 			    NihWatch    *watch,
 			    const char  *path,
 			    struct stat *statbuf)
 {
+	ConfFile *file = NULL;
+	const char *error_path = path;
+	nih_local char *new_path = NULL;
+	int ret;
+
 	nih_assert (source != NULL);
 	nih_assert (watch != NULL);
 	nih_assert (path != NULL);
 	nih_assert (statbuf != NULL);
 
+	/* note that symbolic links are ignored */
 	if (! S_ISREG (statbuf->st_mode))
 		return;
 
-	if (conf_reload_path (source, path) < 0) {
+	new_path = toggle_conf_name (NULL, path);
+	file = (ConfFile *)nih_hash_lookup (source->files, new_path);
+
+	if (is_conf_file_override (path)) {
+		if (! file) {
+			/* override file has no corresponding conf file */
+			nih_debug ("Ignoring orphan override file %s", path);
+			return;
+		}
+
+		/* reload conf file */
+		nih_debug ("Loading configuration file %s", new_path);
+		ret = conf_reload_path (source, new_path, NULL);
+		if (ret < 0) {
+			error_path = new_path;
+			goto error;
+		}
+
+		/* overlay override settings */
+		nih_debug ("Loading override file %s for %s", path, new_path);
+		ret = conf_reload_path (source, new_path, path);
+		if (ret < 0) {
+			error_path = path;
+			goto error;
+		}
+	} else {
+		nih_debug ("Loading configuration and override files for %s", path);
+
+		/* load conf file */
+		nih_debug ("Loading configuration file %s", path);
+		ret = conf_reload_path (source, path, NULL);
+		if (ret < 0) {
+			error_path = path;
+			goto error;
+		}
+
+		/* ensure we ignore directory changes (which won't have overrides. */
+		if (is_conf_file_std (path)) {
+			struct stat st;
+			if (stat (new_path, &st) == 0) {
+				/* overlay override settings */
+				nih_debug ("Loading override file %s for %s", new_path, path);
+				ret = conf_reload_path (source, path, new_path);
+				if (ret < 0) {
+					error_path = new_path;
+					goto error;
+				}
+			}
+
+		}
+	}
+
+	return;
+
+error:
+	{
 		NihError *err;
 
 		err = nih_error_get ();
-		nih_error ("%s: %s: %s", path,
-			   _("Error while loading configuration file"),
-			   err->message);
+		nih_error ("%s: %s: %s", error_path,
+				_("Error while loading configuration file"),
+				err->message);
 		nih_free (err);
+		if (file)
+			nih_unref (file, source);
 	}
 }
 
@@ -585,13 +788,14 @@
  *
  * We lookup the file in our hash table, and if we can find it, perform
  * the usual deletion of it.
-  **/
+ **/
 static void
 conf_delete_handler (ConfSource *source,
 		     NihWatch   *watch,
 		     const char *path)
 {
 	ConfFile *file;
+	nih_local char *new_path = NULL;
 
 	nih_assert (source != NULL);
 	nih_assert (watch != NULL);
@@ -603,7 +807,11 @@
 	 * it's probably a directory or something, so just ignore it.
 	 */
 	file = (ConfFile *)nih_hash_lookup (source->files, path);
-	if (! file) {
+	/* Note we have to be careful to consider deletion of directories too.
+	 * This is handled implicitly by the override check which will return
+	 * false if passed a directory in this case.
+	 */
+	if (! file && ! is_conf_file_override (path)) {
 		if (! strcmp (watch->path, path)) {
 			nih_warn ("%s: %s", source->path,
 				  _("Configuration directory deleted"));
@@ -614,7 +822,30 @@
 		return;
 	}
 
-	nih_unref (file, source);
+	/* non-override files (and directories) are the simple case, so handle
+	 * them and leave.
+	 */ 
+	if (! is_conf_file_override (path)) {
+		nih_unref (file, source);
+		return;
+	}
+
+	/* if an override file is deleted for which there is a corresponding
+	 * conf file, reload the conf file to remove any modifications
+	 * introduced by the override file.
+	 */
+	new_path = toggle_conf_name (NULL, path);
+	file = (ConfFile *)nih_hash_lookup (source->files, new_path);
+
+	if (file) {
+		nih_debug ("Reloading configuration for %s on deletion of overide (%s)",
+				new_path, path);
+
+		if ( conf_reload_path (source, new_path, NULL) < 0 ) {
+			nih_warn ("%s: %s", new_path,
+					_("Unable to reload configuration after override deletion"));
+		}
+	}
 }
 
 /**
@@ -637,22 +868,61 @@
 		   const char  *path,
 		   struct stat *statbuf)
 {
+	ConfFile *file = NULL;
+	nih_local char *new_path = NULL;
+
 	nih_assert (source != NULL);
 	nih_assert (dirname != NULL);
 	nih_assert (path != NULL);
 	nih_assert (statbuf != NULL);
 
+	/* We assume that CONF_EXT_STD files are visited before
+	 * CONF_EXT_OVERRIDE files. Happily, this assumption is currently
+	 * valid since CONF_EXT_STD comes before CONF_EXT_OVERRIDE if ordered
+	 * alphabetically.
+	 *
+	 * If this were ever to change (for example if we decided to
+	 * rename the CONF_EXT_OVERRIDE files to end in ".abc", say), the logic
+	 * in this function would be erroneous since it would never be possible when
+	 * visiting an override file (before a conf file) to lookup a conf file
+	 * in the hash, since the conf file would not yet have been seen and thus would
+	 * not exist in the hash (yet).
+	 */
+	nih_assert (CONF_EXT_STD[1] < CONF_EXT_OVERRIDE[1]);
+
 	if (! S_ISREG (statbuf->st_mode))
 		return 0;
 
-	if (conf_reload_path (source, path) < 0) {
-		NihError *err;
-
-		err = nih_error_get ();
-		nih_error ("%s: %s: %s", path,
-			   _("Error while loading configuration file"),
-			   err->message);
-		nih_free (err);
+	if (is_conf_file_std (path)) {
+		if (conf_reload_path (source, path, NULL) < 0) {
+			NihError *err;
+
+			err = nih_error_get ();
+			nih_error ("%s: %s: %s", path,
+					_("Error while loading configuration file"),
+					err->message);
+			nih_free (err);
+		}
+		return 0;
+	}
+
+	new_path = toggle_conf_name (NULL, path);
+	file = (ConfFile *)nih_hash_lookup (source->files, new_path);
+
+	if (file) {
+		/* we're visiting an override file with an associated conf file that
+		 * has already been loaded, so just overlay the override file. If
+		 * there is no corresponding conf file, we ignore the override file.
+		 */
+		if (conf_reload_path (source, new_path, path) < 0) {
+			NihError *err;
+
+			err = nih_error_get ();
+			nih_error ("%s: %s: %s", new_path,
+					_("Error while reloading configuration file"),
+					err->message);
+			nih_free (err);
+		}
 	}
 
 	return 0;
@@ -662,16 +932,20 @@
 /**
  * conf_reload_path:
  * @source: configuration source,
- * @path: path of file to be reloaded.
+ * @path: path of conf file to be reloaded.
+ * @override_path: if not NULL and @path refers to a path associated with @source,
+ * overlay the contents of @path into the existing @source entry for
+ * @path. If FALSE, discard any existing knowledge of @path.
  *
- * This function is used to parse the file at @path in the context of the
- * given configuration @source.  Necessary ConfFile structures are allocated
- * and attached to @source as appropriate.  CONF_FILE sources always have
- * a single ConfFile when the file exists.
+ * This function is used to parse the file at @path (or @override_path) in the
+ * context of the given configuration @source.  Necessary ConfFile structures
+ * are allocated and attached to @source as appropriate.  CONF_FILE sources
+ * always have a single ConfFile when the file exists.
  *
  * If the file has been parsed before, then the existing item is deleted and
  * freed if the file fails to load, or after the new item has been parsed.
- * Items are not reused between reloads.
+ * Items are only reused between reloads if @override_path is
+ * non-NULL.
  *
  * Physical errors are returned, parse errors are not.
  *
@@ -679,36 +953,47 @@
  **/
 static int
 conf_reload_path (ConfSource *source,
-		  const char *path)
+	  const char *path,
+	  const char *override_path)
 {
-	ConfFile       *file;
+	ConfFile       *file = NULL;
 	nih_local char *buf = NULL;
 	const char     *start, *end;
 	nih_local char *name = NULL;
 	size_t          len, pos, lineno;
 	NihError       *err = NULL;
+	const char     *path_to_load;
 
 	nih_assert (source != NULL);
 	nih_assert (path != NULL);
 
-	/* Look up the old file in memory, and then free it.  In cases
-	 * of failure, we discard it anyway, so there's no particular reason
+	path_to_load = (override_path ? override_path : path);
+
+	/* If there is no corresponding override file, look up the old
+	 * conf file in memory, and then free it.  In cases of failure,
+	 * we discard it anyway, so there's no particular reason
 	 * to keep it around anymore.
+	 *
+	 * Note: if @override_path has been specified, do not
+	 * free the file if found, since we want to _update_ the
+	 * existing entry.
 	 */
 	file = (ConfFile *)nih_hash_lookup (source->files, path);
-	if (file)
+	if (! override_path && file)
 		nih_unref (file, source);
 
 	/* Read the file into memory for parsing, if this fails we don't
 	 * bother creating a new ConfFile structure for it and bail out
 	 * now.
 	 */
-	buf = nih_file_read (NULL, path, &len);
+	buf = nih_file_read (NULL, path_to_load, &len);
 	if (! buf)
 		return -1;
 
-	/* Parse the file, storing the item in a new ConfFile structure. */
-	file = NIH_MUST (conf_file_new (source, path));
+	/* Create a new ConfFile structure (if no @override_path specified) */
+	file = (ConfFile *)nih_hash_lookup (source->files, path);
+	if (! file)
+		file = NIH_MUST (conf_file_new (source, path));
 
 	pos = 0;
 	lineno = 1;
@@ -717,7 +1002,14 @@
 	case CONF_FILE:
 	case CONF_DIR:
 		/* Simple file of options; usually no item attached to it. */
-		nih_debug ("Loading configuration from %s", path);
+		if (override_path) {
+			nih_debug ("Updating configuration for %s from %s",
+					path, override_path);
+		} else {
+			nih_debug ("Loading configuration from %s %s",
+					(source->type == CONF_DIR ? "directory" : "file"), path);
+		}
+
 		if (parse_conf (file, buf, len, &pos, &lineno) < 0)
 			err = nih_error_get ();
 
@@ -735,7 +1027,7 @@
 			start++;
 
 		end = strrchr (start, '.');
-		if (end && (! strcmp (end, ".conf"))) {
+		if (end && IS_CONF_EXT (end)) {
 			name = NIH_MUST (nih_strndup (NULL, start, end - start));
 		} else {
 			name = NIH_MUST (nih_strdup (NULL, start));
@@ -744,8 +1036,16 @@
 		/* Create a new job item and parse the buffer to produce
 		 * the job definition.
 		 */
-		nih_debug ("Loading %s from %s", name, path);
-		file->job = parse_job (NULL, name, buf, len, &pos, &lineno);
+		if (override_path) {
+			nih_debug ("Updating %s (%s) with %s",
+					name, path, override_path);
+		} else {
+			nih_debug ("Loading %s from %s", name, path);
+		}
+
+		file->job = parse_job (NULL, source->session, file->job,
+				name, buf, len, &pos, &lineno);
+
 		if (file->job) {
 			job_class_consider (file->job);
 		} else {
@@ -779,7 +1079,7 @@
 		case PARSE_EXPECTED_OPERATOR:
 		case PARSE_EXPECTED_VARIABLE:
 		case PARSE_MISMATCHED_PARENS:
-			nih_error ("%s:%zi: %s", path, lineno, err->message);
+			nih_error ("%s:%zi: %s", path_to_load, lineno, err->message);
 			nih_free (err);
 			err = NULL;
 			break;
@@ -849,7 +1149,8 @@
 
 /**
  * conf_select_job:
- * @name: name of job class to locate.
+ * @name: name of job class to locate,
+ * @session: session class name belongs to.
  *
  * Select the best available class of a job named @name from the registered
  * configuration sources.
@@ -857,7 +1158,7 @@
  * Returns: Best available job class or NULL if none available.
  **/
 JobClass *
-conf_select_job (const char *name)
+conf_select_job (const char *name, const Session *session)
 {
 	nih_assert (name != NULL);
 
@@ -869,6 +1170,9 @@
 		if (source->type != CONF_JOB_DIR)
 			continue;
 
+		if (source->session != session)
+			continue;
+
 		NIH_HASH_FOREACH (source->files, file_iter) {
 			ConfFile *file = (ConfFile *)file_iter;
 
@@ -882,3 +1186,149 @@
 
 	return NULL;
 }
+
+#ifdef DEBUG
+
+size_t
+debug_count_list_entries (const NihList *list)
+{
+	size_t i = 0;
+	NIH_LIST_FOREACH (list, iter) {
+		i++;
+	}
+	return i;
+}
+
+size_t
+debug_count_hash_entries (const NihHash *hash)
+{
+	size_t i = 0;
+	NIH_HASH_FOREACH_SAFE (hash, iter) {
+		i++;
+	}
+	return i;
+}
+
+void
+debug_show_job_class (const JobClass *job)
+{
+	int i;
+	char **env    = (char **)job->env;
+	char **export = (char **)job->export;
+
+	nih_assert (job);
+
+	nih_debug ("JobClass %p: name='%s', path='%s', task=%d, "
+			"respawn=%d, console=%x, deleted=%d, debug=%d",
+			job, job->name, job->path, job->task,
+			job->respawn, job->console, job->deleted, job->debug);
+
+	nih_debug ("\tstart_on=%p, stop_on=%p, emits=%p, process=%p",
+			job->start_on, job->stop_on, job->emits, job->process);
+
+	nih_debug ("\tauthor='%s', description='%s'",
+			job->author, job->description);
+
+	if (env && *env) {
+		nih_debug ("\tenv:");
+		i = 0;
+		while ( *env ) {
+			nih_debug ("\t\tenv[%d]='%s' (len=%u+1)",
+					i, *env, strlen (*env));
+			env++;
+			++i;
+		}
+	} else {
+		nih_debug ("\tenv: none.");
+	}
+
+
+	if (export && *export) {
+		nih_debug ("\texport:");
+		i = 0;
+		while ( *export ) {
+			nih_debug ("\t\tenv[%d]='%s' (len=%u+1)",
+					i, *export, strlen (*export));
+			export++;
+			++i;
+		}
+	}
+	else {
+		nih_debug ("\texport: none");
+	}
+}
+
+void
+debug_show_job_classes (void)
+{
+	nih_debug ("job_classes:");
+
+	NIH_HASH_FOREACH_SAFE (job_classes, iter) {
+		JobClass *job = (JobClass *)iter;
+		debug_show_job_class (job);
+	}
+}
+
+void
+debug_show_event (const Event *event)
+{
+	nih_assert (event);
+
+	nih_debug ("Event %p: name='%s', progress=%x, failed=%d, "
+			"blockers=%d, blocking=%p",
+			event, event->name, event->progress, event->failed,
+			event->blockers, (void *)&event->blocking);
+}
+
+void
+debug_show_conf_file (const ConfFile *file)
+{
+	nih_assert (file);
+
+	nih_debug ("ConfFile %p: path='%s', source=%p, flag=%x, job=%p",
+			file, file->path, file->source, file->flag, file->job);
+
+	/* Some ConfFile objects won't have any JobClass details, for example,
+	 * the ConfFile object associated with "/etc/init.conf".
+	 */
+	if (! file->job) {
+		nih_debug ("ConfFile %p: job: no JobClass object.", file);
+		return;
+	}
+
+	nih_debug ("ConfFile %p: job:", file);
+	debug_show_job_class (file->job);
+}
+
+void
+debug_show_conf_source (const ConfSource *source)
+{
+	nih_assert (source);
+
+	nih_debug ("ConfSource %p: path='%s', type=%x, flag=%x",
+			source, source->path, source->type, source->flag);
+
+	nih_debug ("ConfSource %p files (%d):", source,
+			debug_count_hash_entries (source->files));
+
+	NIH_HASH_FOREACH (source->files, file_iter) {
+		ConfFile *file = (ConfFile *)file_iter;
+		debug_show_conf_file (file);
+	}
+}
+
+void
+debug_show_conf_sources (void)
+{
+	nih_assert (conf_sources);
+
+	nih_debug ("conf_sources:");
+
+	NIH_LIST_FOREACH (conf_sources, iter) {
+		ConfSource *source = (ConfSource *)iter;
+		debug_show_conf_source (source);
+	}
+}
+
+#endif /* DEBUG */
+

=== modified file 'init/conf.h'
--- init/conf.h	2009-07-09 08:36:52 +0000
+++ init/conf.h	2011-06-06 15:24:28 +0000
@@ -1,6 +1,6 @@
 /* upstart
  *
- * Copyright © 2009 Canonical Ltd.
+ * Copyright © 2010,2011 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -26,6 +26,7 @@
 #include <nih/list.h>
 #include <nih/watch.h>
 
+#include "session.h"
 #include "job_class.h"
 
 
@@ -47,6 +48,7 @@
 /**
  * ConfSource:
  * @entry: list header,
+ * @session: attached session,
  * @path: path to source,
  * @type: type of source,
  * @watch: NihWatch structure for automatic change notification,
@@ -64,6 +66,7 @@
  **/
 typedef struct conf_source {
 	NihList             entry;
+	Session *           session;
 	char               *path;
 	ConfSourceType      type;
 
@@ -122,7 +125,47 @@
 
 int         conf_file_destroy  (ConfFile *file);
 
-JobClass *  conf_select_job    (const char *name);
+JobClass *  conf_select_job    (const char *name, const Session *session);
+
+char *toggle_conf_name         (const void *parent, const char *path)
+	__attribute__ ((warn_unused_result, malloc));
+
+#ifdef DEBUG
+
+/* used for debugging only */
+
+size_t
+debug_count_hash_entries       (const NihHash *hash);
+
+size_t
+debug_count_list_entries       (const NihList *list)
+	__attribute__ ((unused));
+
+void
+debug_show_job_class           (const JobClass *job)
+	__attribute__ ((unused));
+
+void
+debug_show_job_classes         (void)
+	__attribute__ ((unused));
+
+void
+debug_show_event               (const Event *event)
+	__attribute__ ((unused));
+
+void
+debug_show_conf_file(const ConfFile *file)
+	__attribute__ ((unused));
+
+void
+debug_show_conf_source(const ConfSource *source)
+	__attribute__ ((unused));
+
+void
+debug_show_conf_sources(void)
+	__attribute__ ((unused));
+
+#endif
 
 NIH_END_EXTERN
 

=== modified file 'init/control.c'
--- init/control.c	2009-07-11 11:47:12 +0000
+++ init/control.c	2011-06-06 15:24:28 +0000
@@ -2,7 +2,7 @@
  *
  * control.c - D-Bus connections, objects and methods
  *
- * Copyright © 2009 Canonical Ltd.
+ * Copyright © 2009-2011 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -46,6 +46,7 @@
 #include "dbus/upstart.h"
 
 #include "environ.h"
+#include "session.h"
 #include "job_class.h"
 #include "blocked.h"
 #include "conf.h"
@@ -54,12 +55,19 @@
 
 #include "com.ubuntu.Upstart.h"
 
-
 /* Prototypes for static functions */
 static int   control_server_connect (DBusServer *server, DBusConnection *conn);
 static void  control_disconnected   (DBusConnection *conn);
 static void  control_register_all   (DBusConnection *conn);
 
+/**
+ * use_session_bus:
+ *
+ * If TRUE, connect to the D-Bus sessio bus rather than the system bus.
+ *
+ * Used for testing.
+ **/
+int use_session_bus = FALSE;
 
 /**
  * control_server_address:
@@ -78,7 +86,7 @@
 /**
  * control_bus:
  *
- * Open connection to D-Bus system bus.  The connection may be opened with
+ * Open connection to a D-Bus bus.  The connection may be opened with
  * control_bus_open() and if lost will become NULL.
  **/
 DBusConnection *control_bus = NULL;
@@ -86,7 +94,7 @@
 /**
  * control_conns:
  *
- * Open control connections, including the connection to the D-Bus system
+ * Open control connections, including the connection to a D-Bus
  * bus and any private client connections.
  **/
 NihList *control_conns = NULL;
@@ -190,8 +198,9 @@
 /**
  * control_bus_open:
  *
- * Open a connection to the D-Bus system bus and store it in the control_bus
- * global.  The connection is handled automatically in the main loop.
+ * Open a connection to the appropriate D-Bus bus and store it in the
+ * control_bus global. The connection is handled automatically
+ * in the main loop.
  *
  * Returns: zero on success, negative value on raised error.
  **/
@@ -207,10 +216,13 @@
 
 	control_init ();
 
+	control_handle_bus_type ();
+
 	/* Connect to the D-Bus System Bus and hook everything up into
 	 * our own main loop automatically.
 	 */
-	conn = nih_dbus_bus (DBUS_BUS_SYSTEM, control_disconnected);
+	conn = nih_dbus_bus (use_session_bus ? DBUS_BUS_SESSION : DBUS_BUS_SYSTEM,
+			     control_disconnected);
 	if (! conn)
 		return -1;
 
@@ -382,7 +394,9 @@
 			 const char      *name,
 			 char           **job)
 {
-	JobClass *class;
+	Session  *session;
+	JobClass *class = NULL;
+	JobClass *global_class = NULL;
 
 	nih_assert (message != NULL);
 	nih_assert (name != NULL);
@@ -397,8 +411,30 @@
 		return -1;
 	}
 
-	/* Lookup the job and copy its path into the reply */
-	class = (JobClass *)nih_hash_lookup (job_classes, name);
+	/* Get the relevant session */
+	session = session_from_dbus (NULL, message);
+
+	/* Lookup the job */
+	class = (JobClass *)nih_hash_search (job_classes, name, NULL);
+
+	while (class && (class->session != session)) {
+
+		/* Found a match in the global session which may be used
+		 * later if no matching user session job exists.
+		 */
+		if ((! class->session) && (session && ! session->chroot))
+			global_class = class;
+
+		class = (JobClass *)nih_hash_search (job_classes, name,
+				&class->entry);
+	}
+
+	/* If no job with the given name exists in the appropriate
+	 * session, look in the global namespace (aka the NULL session).
+	 */ 
+	if (! class)
+		class = global_class;
+
 	if (! class) {
 		nih_dbus_error_raise_printf (
 			DBUS_INTERFACE_UPSTART ".Error.UnknownJob",
@@ -406,6 +442,7 @@
 		return -1;
 	}
 
+	/* Copy the path */
 	*job = nih_strdup (message, class->path);
 	if (! *job)
 		nih_return_system_error (-1);
@@ -432,6 +469,7 @@
 		      NihDBusMessage   *message,
 		      char           ***jobs)
 {
+	Session *session;
 	char   **list;
 	size_t   len;
 
@@ -445,9 +483,16 @@
 	if (! list)
 		nih_return_system_error (-1);
 
+	/* Get the relevant session */
+	session = session_from_dbus (NULL, message);
+
 	NIH_HASH_FOREACH (job_classes, iter) {
 		JobClass *class = (JobClass *)iter;
 
+		if ((class->session || (session && session->chroot))
+		    && (class->session != session))
+			continue;
+
 		if (! nih_str_array_add (&list, message, &len,
 					 class->path)) {
 			nih_error_raise_system ();
@@ -520,6 +565,9 @@
 	if (! event)
 		nih_return_system_error (-1);
 
+	/* Obtain the session */
+	event->session = session_from_dbus (NULL, message);
+
 	if (wait) {
 		blocked = blocked_new (event, BLOCKED_EMIT_METHOD, message);
 		if (! blocked) {
@@ -669,3 +717,18 @@
 
 	return 0;
 }
+
+/**
+ * control_handle_bus_type:
+ *
+ * Determine D-Bus bus type to connect to.
+ **/
+void
+control_handle_bus_type (void)
+{
+	if (getenv (USE_SESSION_BUS_ENV))
+		use_session_bus = TRUE;
+
+	if (use_session_bus)
+		nih_debug ("Using session bus");
+}

=== modified file 'init/control.h'
--- init/control.h	2009-07-09 08:36:52 +0000
+++ init/control.h	2011-06-06 15:24:28 +0000
@@ -1,6 +1,6 @@
 /* upstart
  *
- * Copyright © 2009 Canonical Ltd.
+ * Copyright © 2009-2011 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -27,6 +27,18 @@
 #include <nih-dbus/dbus_connection.h>
 #include <nih-dbus/dbus_message.h>
 
+/**
+ * USE_SESSION_BUS_ENV:
+ *
+ * If this environment variable is set to any value, connect to
+ * D-Bus session bus rather than the system bus.
+ *
+ * Used for testing.
+ **/
+#ifndef USE_SESSION_BUS_ENV
+#define USE_SESSION_BUS_ENV "UPSTART_USE_SESSION_BUS"
+#endif
+
 
 NIH_BEGIN_EXTERN
 
@@ -72,6 +84,8 @@
 				   const char *log_priority)
 	__attribute__ ((warn_unused_result));
 
+void control_handle_bus_type      (void);
+
 NIH_END_EXTERN
 
 #endif /* INIT_CONTROL_H */

=== modified file 'init/environ.c'
--- init/environ.c	2011-03-16 22:42:48 +0000
+++ init/environ.c	2011-06-06 15:24:28 +0000
@@ -2,7 +2,6 @@
  *
  * environ.c - environment table utilities
  *
- * Copyright © 2011 Google Inc.
  * Copyright © 2009 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *

=== modified file 'init/environ.h'
--- init/environ.h	2011-03-16 22:42:48 +0000
+++ init/environ.h	2011-06-06 15:24:28 +0000
@@ -1,6 +1,5 @@
 /* upstart
  *
- * Copyright © 2011 Google Inc.
  * Copyright © 2009 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *

=== modified file 'init/event.c'
--- init/event.c	2010-12-14 15:32:41 +0000
+++ init/event.c	2011-06-06 15:24:28 +0000
@@ -123,6 +123,8 @@
 
 	nih_list_init (&event->entry);
 
+	event->session = NULL;
+
 	event->progress = EVENT_PENDING;
 	event->failed = FALSE;
 
@@ -293,6 +295,13 @@
 	NIH_HASH_FOREACH_SAFE (job_classes, iter) {
 		JobClass *class = (JobClass *)iter;
 
+		/* Only affect jobs within the same session as the event
+		 * unless the event has no session, in which case do them
+		 * all.
+		 */
+		if (event->session && (class->session != event->session))
+			continue;
+
 		/* We stop first so that if an event is listed both as a
 		 * stop and start event, it causes an active running process
 		 * to be killed, the stop script then the start script to be
@@ -470,6 +479,7 @@
 			failed = NIH_MUST (nih_sprintf (NULL, "%s/failed",
 							event->name));
 			new_event = NIH_MUST (event_new (NULL, failed, NULL));
+			new_event->session = event->session;
 
 			if (event->env)
 				new_event->env = NIH_MUST (nih_str_array_copy (

=== modified file 'init/event.h'
--- init/event.h	2009-07-09 08:36:52 +0000
+++ init/event.h	2011-06-06 15:24:28 +0000
@@ -1,6 +1,6 @@
 /* upstart
  *
- * Copyright © 2009 Canonical Ltd.
+ * Copyright © 2010 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -23,6 +23,8 @@
 #include <nih/macros.h>
 #include <nih/list.h>
 
+#include "session.h"
+
 
 /**
  * EventProgress:
@@ -40,6 +42,7 @@
 /**
  * Event:
  * @entry: list header,
+ * @session: session the event is attached to,
  * @name: string name of the event,
  * @env: NULL-terminated array of environment variables,
  * @progress: progress of event,
@@ -61,6 +64,7 @@
 typedef struct event {
 	NihList          entry;
 
+	Session *        session;
  	char            *name;
 	char           **env;
 

=== modified file 'init/job.c'
--- init/job.c	2010-12-14 15:32:41 +0000
+++ init/job.c	2011-06-06 15:24:28 +0000
@@ -2,7 +2,7 @@
  *
  * job.c - core state machine of tasks and services
  *
- * Copyright © 2010 Canonical Ltd.
+ * Copyright © 2010,2011 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -47,6 +47,7 @@
 #include "events.h"
 #include "environ.h"
 #include "process.h"
+#include "session.h"
 #include "job_class.h"
 #include "job.h"
 #include "job_process.h"
@@ -99,8 +100,14 @@
 
 	job->class = class;
 
-	job->path = nih_dbus_path (job, DBUS_PATH_UPSTART, "jobs",
-				   class->name, job->name, NULL);
+	if (job->class->session && job->class->session->chroot) {
+		/* JobClass already contains a valid D-Bus path prefix for the job */
+		job->path = nih_dbus_path (job, class->path, job->name, NULL);
+	} else {
+		job->path = nih_dbus_path (job, DBUS_PATH_UPSTART, "jobs",
+				class->name, job->name, NULL);
+	}
+
 	if (! job->path)
 		goto error;
 
@@ -906,6 +913,7 @@
 	}
 
 	event = NIH_MUST (event_new (NULL, name, env));
+	event->session = job->class->session;
 
 	if (block) {
 		Blocked *blocked;
@@ -1102,11 +1110,22 @@
 	   NihDBusMessage  *message,
 	   int              wait)
 {
+	Session *session;
 	Blocked *blocked = NULL;
 
 	nih_assert (job != NULL);
 	nih_assert (message != NULL);
 
+	/* Don't permit out-of-session modification */
+	session = session_from_dbus (NULL, message);
+	if (session != job->class->session) {
+		nih_dbus_error_raise_printf (
+			DBUS_INTERFACE_UPSTART ".Error.PermissionDenied",
+			_("You do not have permission to modify job: %s"),
+			job_name (job));
+		return -1;
+	}
+
 	if (job->goal == JOB_START) {
 		nih_dbus_error_raise_printf (
 			DBUS_INTERFACE_UPSTART ".Error.AlreadyStarted",
@@ -1166,11 +1185,22 @@
 	  NihDBusMessage *message,
 	  int             wait)
 {
+	Session *session;
 	Blocked *blocked = NULL;
 
 	nih_assert (job != NULL);
 	nih_assert (message != NULL);
 
+	/* Don't permit out-of-session modification */
+	session = session_from_dbus (NULL, message);
+	if (session != job->class->session) {
+		nih_dbus_error_raise_printf (
+			DBUS_INTERFACE_UPSTART ".Error.PermissionDenied",
+			_("You do not have permission to modify job: %s"),
+			job_name (job));
+		return -1;
+	}
+
 	if (job->goal == JOB_STOP) {
 		nih_dbus_error_raise_printf (
 			DBUS_INTERFACE_UPSTART ".Error.AlreadyStopped",
@@ -1231,11 +1261,22 @@
 	     NihDBusMessage *message,
 	     int             wait)
 {
+	Session *session;
 	Blocked *blocked = NULL;
 
 	nih_assert (job != NULL);
 	nih_assert (message != NULL);
 
+	/* Don't permit out-of-session modification */
+	session = session_from_dbus (NULL, message);
+	if (session != job->class->session) {
+		nih_dbus_error_raise_printf (
+			DBUS_INTERFACE_UPSTART ".Error.PermissionDenied",
+			_("You do not have permission to modify job: %s"),
+			job_name (job));
+		return -1;
+	}
+
 	if (job->goal == JOB_STOP) {
 		nih_dbus_error_raise_printf (
 			DBUS_INTERFACE_UPSTART ".Error.AlreadyStopped",

=== modified file 'init/job.h'
--- init/job.h	2009-07-03 16:38:02 +0000
+++ init/job.h	2011-06-06 15:24:28 +0000
@@ -1,6 +1,6 @@
 /* upstart
  *
- * Copyright © 2009 Canonical Ltd.
+ * Copyright © 2010 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
  * This program is free software; you can redistribute it and/or modify

=== modified file 'init/job_class.c'
--- init/job_class.c	2011-05-12 20:42:28 +0000
+++ init/job_class.c	2011-06-06 15:24:28 +0000
@@ -2,7 +2,7 @@
  *
  * job_class.c - job class definition handling
  *
- * Copyright © 2010 Canonical Ltd.
+ * Copyright © 2010,2011 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -45,6 +45,7 @@
 
 #include "environ.h"
 #include "process.h"
+#include "session.h"
 #include "job_class.h"
 #include "job.h"
 #include "event_operator.h"
@@ -100,7 +101,7 @@
 
 /* Prototypes for static functions */
 static void job_class_add    (JobClass *class);
-static int  job_class_remove (JobClass *class);
+static int  job_class_remove (JobClass *class, const Session *session);
 
 
 /**
@@ -128,13 +129,15 @@
 
 /**
  * job_class_new:
+ *
  * @parent: parent for new job class,
- * @name: name of new job class.
+ * @name: name of new job class,
+ * @session: session.
  *
- * Allocates and returns a new JobClass structure with the @name given.
- * It will not be automatically added to the job classes table, it is up
- * to the caller to ensure this is done using job_class_register() once
- * the class has been set up.
+ * Allocates and returns a new JobClass structure with the given @name
+ * and @session. It will not be automatically added to the job classes
+ * table, it is up to the caller to ensure this is done using
+ * job_class_register() once the class has been set up.
  *
  * If @parent is not NULL, it should be a pointer to another object which
  * will be used as a parent for the returned job class.  When all parents
@@ -145,7 +148,8 @@
  **/
 JobClass *
 job_class_new (const void *parent,
-	       const char *name)
+	       const char *name,
+	       Session    *session)
 {
 	JobClass *class;
 	int       i;
@@ -165,8 +169,41 @@
 	if (! class->name)
 		goto error;
 
-	class->path = nih_dbus_path (class, DBUS_PATH_UPSTART, "jobs",
-				     class->name, NULL);
+	class->session = session;
+	if (class->session
+	    && class->session->chroot
+	    && class->session->user) {
+		nih_local char *uid = NULL;
+
+		uid = nih_sprintf (NULL, "%d", class->session->user);
+		if (! uid)
+			goto error;
+
+		class->path = nih_dbus_path (class, DBUS_PATH_UPSTART, "jobs",
+					     session->chroot, uid,
+					     class->name, NULL);
+
+	} else if (class->session
+		   && class->session->chroot) {
+		class->path = nih_dbus_path (class, DBUS_PATH_UPSTART, "jobs",
+					     session->chroot,
+					     class->name, NULL);
+
+	} else if (class->session
+		   && class->session->user) {
+		nih_local char *uid = NULL;
+
+		uid = nih_sprintf (NULL, "%d", class->session->user);
+		if (! uid)
+			goto error;
+
+		class->path = nih_dbus_path (class, DBUS_PATH_UPSTART, "jobs",
+					     uid, class->name, NULL);
+
+	} else {
+		class->path = nih_dbus_path (class, DBUS_PATH_UPSTART, "jobs",
+					     class->name, NULL);
+	}
 	if (! class->path)
 		goto error;
 
@@ -222,7 +259,7 @@
 	class->chdir = NULL;
 
 	class->deleted = FALSE;
-	class->debug   = FALSE;
+	class->debug = FALSE;
 
 	return class;
 
@@ -245,19 +282,27 @@
 int
 job_class_consider (JobClass *class)
 {
-	JobClass *registered, *best;
+	JobClass *registered = NULL, *best = NULL;
 
 	nih_assert (class != NULL);
 
 	job_class_init ();
 
-	best = conf_select_job (class->name);
+	best = conf_select_job (class->name, class->session);
 	nih_assert (best != NULL);
-
-	registered = (JobClass *)nih_hash_lookup (job_classes, class->name);
+	nih_assert (best->session == class->session);
+
+	registered = (JobClass *)nih_hash_search (job_classes, class->name, NULL);
+
+	/* If we found an entry, ensure we only consider the appropriate session */
+	while (registered && registered->session != class->session)
+	{
+		registered = (JobClass *)nih_hash_search (job_classes, class->name, &registered->entry);
+	}
+
 	if (registered != best) {
 		if (registered)
-			if (! job_class_remove (registered))
+			if (! job_class_remove (registered, class->session))
 				return FALSE;
 
 		job_class_add (best);
@@ -282,18 +327,25 @@
 int
 job_class_reconsider (JobClass *class)
 {
-	JobClass *registered, *best;
+	JobClass *registered = NULL, *best = NULL;
 
 	nih_assert (class != NULL);
 
 	job_class_init ();
 
-	best = conf_select_job (class->name);
-
-	registered = (JobClass *)nih_hash_lookup (job_classes, class->name);
+	best = conf_select_job (class->name, class->session);
+
+	registered = (JobClass *)nih_hash_search (job_classes, class->name, NULL);
+
+	/* If we found an entry, ensure we only consider the appropriate session */
+	while (registered && registered->session != class->session)
+	{
+		registered = (JobClass *)nih_hash_search (job_classes, class->name, &registered->entry);
+	}
+
 	if (registered == class) {
 		if (class != best) {
-			if (! job_class_remove (class))
+			if (! job_class_remove (class, class->session))
 				return FALSE;
 
 			job_class_add (best);
@@ -334,19 +386,24 @@
 
 /**
  * job_class_remove:
- * @class: class to remove.
+ * @class: class to remove,
+ * @session: Session of @class.
  *
  * Removes @class from the hash table and unregisters it from all current
  * D-Bus connections.
  *
  * Returns: TRUE if class could be unregistered, FALSE if there are
- * active instances that prevent unregistration.
+ * active instances that prevent unregistration, or if @session
+ * does not match the session associated with @class.
  **/
 static int
-job_class_remove (JobClass *class)
+job_class_remove (JobClass *class, const Session *session)
 {
 	nih_assert (class != NULL);
 
+	if (class->session != session)
+		return FALSE;
+
 	control_init ();
 
 	/* Return if we have any active instances */
@@ -696,6 +753,7 @@
 		 char * const    *env,
 		 int              wait)
 {
+	Session         *session;
 	Blocked         *blocked = NULL;
 	Job             *job;
 	nih_local char **start_env = NULL;
@@ -706,6 +764,16 @@
 	nih_assert (message != NULL);
 	nih_assert (env != NULL);
 
+	/* Don't permit out-of-session modification */
+	session = session_from_dbus (NULL, message);
+	if (session != class->session) {
+		nih_dbus_error_raise_printf (
+			DBUS_INTERFACE_UPSTART ".Error.PermissionDenied",
+			_("You do not have permission to modify job: %s"),
+			class->name);
+		return -1;
+	}
+
 	/* Verify that the environment is valid */
 	if (! environ_all_valid (env)) {
 		nih_dbus_error_raise_printf (DBUS_ERROR_INVALID_ARGS,
@@ -815,6 +883,7 @@
 		char * const   *env,
 		int             wait)
 {
+	Session         *session;
 	Blocked         *blocked = NULL;
 	Job             *job;
 	nih_local char **stop_env = NULL;
@@ -825,6 +894,16 @@
 	nih_assert (message != NULL);
 	nih_assert (env != NULL);
 
+	/* Don't permit out-of-session modification */
+	session = session_from_dbus (NULL, message);
+	if (session != class->session) {
+		nih_dbus_error_raise_printf (
+			DBUS_INTERFACE_UPSTART ".Error.PermissionDenied",
+			_("You do not have permission to modify job: %s"),
+			class->name);
+		return -1;
+	}
+
 	/* Verify that the environment is valid */
 	if (! environ_all_valid (env)) {
 		nih_dbus_error_raise_printf (DBUS_ERROR_INVALID_ARGS,
@@ -939,6 +1018,7 @@
 		   char * const    *env,
 		   int              wait)
 {
+	Session         *session;
 	Blocked         *blocked = NULL;
 	Job             *job;
 	nih_local char **restart_env = NULL;
@@ -949,6 +1029,16 @@
 	nih_assert (message != NULL);
 	nih_assert (env != NULL);
 
+	/* Don't permit out-of-session modification */
+	session = session_from_dbus (NULL, message);
+	if (session != class->session) {
+		nih_dbus_error_raise_printf (
+			DBUS_INTERFACE_UPSTART ".Error.PermissionDenied",
+			_("You do not have permission to modify job: %s"),
+			class->name);
+		return -1;
+	}
+
 	/* Verify that the environment is valid */
 	if (! environ_all_valid (env)) {
 		nih_dbus_error_raise_printf (DBUS_ERROR_INVALID_ARGS,

=== modified file 'init/job_class.h'
--- init/job_class.h	2011-05-12 20:42:28 +0000
+++ init/job_class.h	2011-06-06 15:24:28 +0000
@@ -35,6 +35,7 @@
 
 #include "process.h"
 #include "event_operator.h"
+#include "session.h"
 
 
 /**
@@ -71,6 +72,7 @@
  * @entry: list header,
  * @name: unique name,
  * @path: path of D-Bus object,
+ * @session: attached session,
  * @instance: pattern to uniquely identify multiple instances,
  * @instances: hash table of active instances,
  * @description: description; intended for humans,
@@ -110,6 +112,7 @@
 
 	char           *name;
 	char           *path;
+	Session *       session;
 
 	char           *instance;
 	NihHash        *instances;
@@ -161,7 +164,8 @@
 void        job_class_init                 (void);
 
 JobClass  * job_class_new                  (const void *parent,
-					    const char *name)
+					    const char *name,
+					    Session *session)
 	__attribute__ ((warn_unused_result, malloc));
 
 int         job_class_consider             (JobClass *class);

=== modified file 'init/job_process.c'
--- init/job_process.c	2011-05-12 20:42:28 +0000
+++ init/job_process.c	2011-06-06 15:24:28 +0000
@@ -2,7 +2,6 @@
  *
  * job_process.c - job process handling
  *
- * Copyright © 2011 Google Inc.
  * Copyright © 2011 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
@@ -41,6 +40,7 @@
 #include <unistd.h>
 #include <utmp.h>
 #include <utmpx.h>
+#include <pwd.h>
 
 #include <nih/macros.h>
 #include <nih/alloc.h>
@@ -539,6 +539,16 @@
 		}
 	}
 
+	/* Handle changing a chroot session job prior to dealing with
+	 * the 'chroot' stanza.
+	 */
+	if (class->session && class->session->chroot) {
+		if (chroot (class->session->chroot) < 0) {
+			nih_error_raise_system ();
+			job_process_error_abort (fds[1], JOB_PROCESS_ERROR_CHROOT, 0);
+		}
+	}
+
 	/* Change the root directory, confining path resolution within it;
 	 * we do this before the working directory call so that is always
 	 * relative to the new root.
@@ -594,6 +604,54 @@
 		}
 	}
 
+	/* Handle unprivileged user job by dropping privileges to
+	 * their level.
+	 */
+	if (class->session && class->session->user) {
+		uid_t uid = class->session->user;
+		struct passwd *pw = NULL;
+
+		/* D-Bus does not expose a public API call to allow
+		 * us to query a users primary group.
+		 * _dbus_user_info_fill_uid () seems to exist for this
+		 * purpose, but is a "secret" API. It is unclear why
+		 * D-Bus neglects the gid when it allows the uid
+		 * to be queried directly.
+		 *
+		 * Our only recourse is to disallow user sessions in a
+		 * chroot and assume that all other user sessions
+		 * originate from the local system. In this way, we can
+		 * bypass D-Bus and use getpwuid ().
+		 */
+
+		if (class->session->chroot) {
+			/* We cannot determine the group id of the user
+			 * session in the chroot via D-Bus, so disallow
+			 * all jobs in such an environment.
+			 */
+			_nih_error_raise (__FILE__, __LINE__, __FUNCTION__,
+					EPERM, strerror (EPERM));
+		}
+
+		pw = getpwuid (uid);
+
+		if (!pw)
+			nih_return_system_error (-1);
+
+		nih_assert (pw->pw_uid == uid);
+
+		if (uid && setuid (uid) < 0) {
+			nih_error_raise_system ();
+			job_process_error_abort (fds[1], JOB_PROCESS_ERROR_SETUID, 0);
+		}
+
+		if (pw->pw_gid && setgid (pw->pw_gid) < 0) {
+			nih_error_raise_system ();
+			job_process_error_abort (fds[1], JOB_PROCESS_ERROR_SETGID, 0);
+		}
+	}
+
+
 	/* Execute the process, if we escape from here it failed */
 	if (execvp (argv[0], argv) < 0) {
 		nih_error_raise_system ();

=== modified file 'init/job_process.h'
--- init/job_process.h	2011-05-12 19:21:16 +0000
+++ init/job_process.h	2011-06-06 15:24:28 +0000
@@ -1,7 +1,6 @@
 /* upstart
  *
- * Copyright © 2011 Google Inc.
- * Copyright © 2009 Canonical Ltd.
+ * Copyright © 2009,2010,2011 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -57,7 +56,9 @@
 	JOB_PROCESS_ERROR_CHROOT,
 	JOB_PROCESS_ERROR_CHDIR,
 	JOB_PROCESS_ERROR_PTRACE,
-	JOB_PROCESS_ERROR_EXEC
+	JOB_PROCESS_ERROR_EXEC,
+	JOB_PROCESS_ERROR_SETUID,
+	JOB_PROCESS_ERROR_SETGID,
 } JobProcessErrorType;
 
 /**

=== modified file 'init/main.c'
--- init/main.c	2011-03-16 22:54:56 +0000
+++ init/main.c	2011-06-06 15:24:28 +0000
@@ -1,7 +1,6 @@
 /* upstart
  *
- * Copyright © 2011 Google Inc.
- * Copyright © 2010 Canonical Ltd.
+ * Copyright © 2009-2011 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -71,6 +70,8 @@
 static void usr1_handler    (void *data, NihSignal *signal);
 #endif /* DEBUG */
 
+static void handle_confdir  (void);
+
 
 /**
  * argv0:
@@ -89,14 +90,55 @@
 static int restart = FALSE;
 
 
+extern int disable_sessions;
+
+/**
+ * conf_dir:
+ *
+ * Full path to job configuration file directory.
+ *
+ **/
+static char *conf_dir = NULL;
+
+/**
+ * initial_event:
+ *
+ * Alternate event to emit at startup (rather than STARTUP_EVENT).
+ **/
+static char *initial_event = NULL;
+
+/**
+ * disable_startup_event:
+ *
+ * If TRUE, do not emit a startup event.
+ **/
+static int disable_startup_event = FALSE;
+
+extern int use_session_bus;
+
 /**
  * options:
  *
  * Command-line options we accept.
  **/
 static NihOption options[] = {
+	{ 0, "confdir", N_("specify alternative directory to load configuration files from"),
+		NULL, "DIR", &conf_dir, NULL },
+
+	{ 0, "no-sessions", N_("Disable user and chroot sessions"),
+		NULL, NULL, &disable_sessions, NULL },
+
+	{ 0, "no-startup-event", N_("do not emit any startup event (for testing)"),
+		NULL, NULL, &disable_startup_event, NULL },
+
 	{ 0, "restart", NULL, NULL, NULL, &restart, NULL },
 
+	{ 0, "session", N_("use D-Bus session bus rather than system bus (for testing)"),
+		NULL, NULL, &use_session_bus, NULL },
+
+	{ 0, "startup-event", N_("specify an alternative initial event (for testing)"),
+		NULL, "NAME", &initial_event, NULL },
+
 	/* Ignore invalid options */
 	{ '-', "--", NULL, NULL, NULL, NULL, NULL },
 
@@ -124,94 +166,105 @@
 	if (! args)
 		exit (1);
 
+	handle_confdir ();
+	control_handle_bus_type ();
+
 #ifndef DEBUG
-	/* Check we're root */
-	if (getuid ()) {
-		nih_fatal (_("Need to be root"));
-		exit (1);
-	}
-
-	/* Check we're process #1 */
-	if (getpid () > 1) {
-		execv (TELINIT, argv);
-		/* Ignore failure, probably just that telinit doesn't exist */
-
-		nih_fatal (_("Not being executed as init"));
-		exit (1);
-	}
-
-	/* Clear our arguments from the command-line, so that we show up in
-	 * ps or top output as /sbin/init, with no extra flags.
-	 *
-	 * This is a very Linux-specific trick; by deleting the NULL
-	 * terminator at the end of the last argument, we fool the kernel
-	 * into believing we used a setproctitle()-a-like to extend the
-	 * argument space into the environment space, and thus make it use
-	 * strlen() instead of its own assumed length.  In fact, we've done
-	 * the exact opposite, and shrunk the command line length to just that
-	 * of whatever is in argv[0].
-	 *
-	 * If we don't do this, and just write \0 over the rest of argv, for
-	 * example; the command-line length still includes those \0s, and ps
-	 * will show whitespace in their place.
-	 */
-	if (argc > 1) {
-		char *arg_end;
-
-		arg_end = argv[argc-1] + strlen (argv[argc-1]);
-		*arg_end = ' ';
-	}
-
-
-	/* Become the leader of a new session and process group, shedding
-	 * any controlling tty (which we shouldn't have had anyway - but
-	 * you never know what initramfs did).
-	 */
-	setsid ();
-
-	/* Set the standard file descriptors to the ordinary console device,
-	 * resetting it to sane defaults unless we're inheriting from another
-	 * init process which we know left it in a sane state.
-	 */
-	if (system_setup_console (CONSOLE_OUTPUT, (! restart)) < 0)
-		nih_free (nih_error_get ());
-
-	/* Set the PATH environment variable */
-	setenv ("PATH", PATH, TRUE);
-
-	/* Switch to the root directory in case we were started from some
-	 * strange place, or worse, some directory in the initramfs that's
-	 * going to go away soon.
-	 */
-	if (chdir ("/"))
-		nih_warn ("%s: %s", _("Unable to set root directory"),
-			  strerror (errno));
-
-	/* Mount the /proc and /sys filesystems, which are pretty much
-	 * essential for any Linux system; not to mention used by
-	 * ourselves.
-	 */
-	if (system_mount ("proc", "/proc") < 0) {
-		NihError *err;
-
-		err = nih_error_get ();
-		nih_warn ("%s: %s", _("Unable to mount /proc filesystem"),
-			  err->message);
-		nih_free (err);
-	}
-
-	if (system_mount ("sysfs", "/sys") < 0) {
-		NihError *err;
-
-		err = nih_error_get ();
-		nih_warn ("%s: %s", _("Unable to mount /sys filesystem"),
-			  err->message);
-		nih_free (err);
-	}
+	if (use_session_bus == FALSE) {
+
+		/* Check we're root */
+		if (getuid ()) {
+			nih_fatal (_("Need to be root"));
+			exit (1);
+		}
+
+		/* Check we're process #1 */
+		if (getpid () > 1) {
+			execv (TELINIT, argv);
+			/* Ignore failure, probably just that telinit doesn't exist */
+
+			nih_fatal (_("Not being executed as init"));
+			exit (1);
+		}
+
+		/* Clear our arguments from the command-line, so that we show up in
+		 * ps or top output as /sbin/init, with no extra flags.
+		 *
+		 * This is a very Linux-specific trick; by deleting the NULL
+		 * terminator at the end of the last argument, we fool the kernel
+		 * into believing we used a setproctitle()-a-like to extend the
+		 * argument space into the environment space, and thus make it use
+		 * strlen() instead of its own assumed length.  In fact, we've done
+		 * the exact opposite, and shrunk the command line length to just that
+		 * of whatever is in argv[0].
+		 *
+		 * If we don't do this, and just write \0 over the rest of argv, for
+		 * example; the command-line length still includes those \0s, and ps
+		 * will show whitespace in their place.
+		 */
+		if (argc > 1) {
+			char *arg_end;
+
+			arg_end = argv[argc-1] + strlen (argv[argc-1]);
+			*arg_end = ' ';
+		}
+
+
+		/* Become the leader of a new session and process group, shedding
+		 * any controlling tty (which we shouldn't have had anyway - but
+		 * you never know what initramfs did).
+		 */
+		setsid ();
+
+		/* Set the standard file descriptors to the ordinary console device,
+		 * resetting it to sane defaults unless we're inheriting from another
+		 * init process which we know left it in a sane state.
+		 */
+		if (system_setup_console (CONSOLE_OUTPUT, (! restart)) < 0)
+			nih_free (nih_error_get ());
+
+		/* Set the PATH environment variable */
+		setenv ("PATH", PATH, TRUE);
+
+		/* Switch to the root directory in case we were started from some
+		 * strange place, or worse, some directory in the initramfs that's
+		 * going to go away soon.
+		 */
+		if (chdir ("/"))
+			nih_warn ("%s: %s", _("Unable to set root directory"),
+				strerror (errno));
+
+		/* Mount the /proc and /sys filesystems, which are pretty much
+		 * essential for any Linux system; not to mention used by
+		 * ourselves.
+		 */
+		if (system_mount ("proc", "/proc") < 0) {
+			NihError *err;
+
+			err = nih_error_get ();
+			nih_warn ("%s: %s", _("Unable to mount /proc filesystem"),
+				err->message);
+			nih_free (err);
+		}
+
+		if (system_mount ("sysfs", "/sys") < 0) {
+			NihError *err;
+
+			err = nih_error_get ();
+			nih_warn ("%s: %s", _("Unable to mount /sys filesystem"),
+				err->message);
+			nih_free (err);
+		}
+	} else {
+		nih_log_set_priority (NIH_LOG_DEBUG);
+		nih_debug ("Running with UID %d as PID %d (PPID %d)",
+				(int)getuid (), (int)getpid (), (int)getppid ());
+	}
+
 #else /* DEBUG */
 	nih_log_set_priority (NIH_LOG_DEBUG);
-	nih_debug ("Running as PID %d (PPID %d)",
-		(int)getpid (), (int)getppid ());
+	nih_debug ("Running with UID %d as PID %d (PPID %d)",
+		(int)getuid (), (int)getpid (), (int)getppid ());
 #endif /* DEBUG */
 
 
@@ -223,11 +276,13 @@
 		nih_signal_reset ();
 
 #ifndef DEBUG
-	/* Catch fatal errors immediately rather than waiting for a new
-	 * iteration through the main loop.
-	 */
-	nih_signal_set_handler (SIGSEGV, crash_handler);
-	nih_signal_set_handler (SIGABRT, crash_handler);
+	if (use_session_bus == FALSE) {
+		/* Catch fatal errors immediately rather than waiting for a new
+		 * iteration through the main loop.
+		 */
+		nih_signal_set_handler (SIGSEGV, crash_handler);
+		nih_signal_set_handler (SIGABRT, crash_handler);
+	}
 #endif /* DEBUG */
 
 	/* Don't ignore SIGCHLD or SIGALRM, but don't respond to them
@@ -238,33 +293,35 @@
 	nih_signal_set_handler (SIGALRM, nih_signal_handler);
 
 #ifndef DEBUG
-	/* Ask the kernel to send us SIGINT when control-alt-delete is
-	 * pressed; generate an event with the same name.
-	 */
-	reboot (RB_DISABLE_CAD);
-	nih_signal_set_handler (SIGINT, nih_signal_handler);
-	NIH_MUST (nih_signal_add_handler (NULL, SIGINT, cad_handler, NULL));
-
-	/* Ask the kernel to send us SIGWINCH when alt-uparrow is pressed;
-	 * generate a keyboard-request event.
-	 */
-	if (ioctl (0, KDSIGACCEPT, SIGWINCH) == 0) {
-		nih_signal_set_handler (SIGWINCH, nih_signal_handler);
-		NIH_MUST (nih_signal_add_handler (NULL, SIGWINCH,
-						  kbd_handler, NULL));
+	if (use_session_bus == FALSE) {
+		/* Ask the kernel to send us SIGINT when control-alt-delete is
+		 * pressed; generate an event with the same name.
+		 */
+		reboot (RB_DISABLE_CAD);
+		nih_signal_set_handler (SIGINT, nih_signal_handler);
+		NIH_MUST (nih_signal_add_handler (NULL, SIGINT, cad_handler, NULL));
+
+		/* Ask the kernel to send us SIGWINCH when alt-uparrow is pressed;
+		 * generate a keyboard-request event.
+		 */
+		if (ioctl (0, KDSIGACCEPT, SIGWINCH) == 0) {
+			nih_signal_set_handler (SIGWINCH, nih_signal_handler);
+			NIH_MUST (nih_signal_add_handler (NULL, SIGWINCH,
+						kbd_handler, NULL));
+		}
+
+		/* powstatd sends us SIGPWR when it changes /etc/powerstatus */
+		nih_signal_set_handler (SIGPWR, nih_signal_handler);
+		NIH_MUST (nih_signal_add_handler (NULL, SIGPWR, pwr_handler, NULL));
+
+		/* SIGHUP instructs us to re-load our configuration */
+		nih_signal_set_handler (SIGHUP, nih_signal_handler);
+		NIH_MUST (nih_signal_add_handler (NULL, SIGHUP, hup_handler, NULL));
+
+		/* SIGUSR1 instructs us to reconnect to D-Bus */
+		nih_signal_set_handler (SIGUSR1, nih_signal_handler);
+		NIH_MUST (nih_signal_add_handler (NULL, SIGUSR1, usr1_handler, NULL));
 	}
-
-	/* powstatd sends us SIGPWR when it changes /etc/powerstatus */
-	nih_signal_set_handler (SIGPWR, nih_signal_handler);
-	NIH_MUST (nih_signal_add_handler (NULL, SIGPWR, pwr_handler, NULL));
-
-	/* SIGHUP instructs us to re-load our configuration */
-	nih_signal_set_handler (SIGHUP, nih_signal_handler);
-	NIH_MUST (nih_signal_add_handler (NULL, SIGHUP, hup_handler, NULL));
-
-	/* SIGUSR1 instructs us to reconnect to D-Bus */
-	nih_signal_set_handler (SIGUSR1, nih_signal_handler);
-	NIH_MUST (nih_signal_add_handler (NULL, SIGUSR1, usr1_handler, NULL));
 #endif /* DEBUG */
 
 
@@ -279,25 +336,27 @@
 
 	/* Read configuration */
 	NIH_MUST (conf_source_new (NULL, CONFFILE, CONF_FILE));
-	NIH_MUST (conf_source_new (NULL, CONFDIR, CONF_JOB_DIR));
+	NIH_MUST (conf_source_new (NULL, conf_dir, CONF_JOB_DIR));
 
 	conf_reload ();
 
 	/* Create a listening server for private connections. */
-	while (control_server_open () < 0) {
-		NihError *err;
+	if (use_session_bus == FALSE) {
+		while (control_server_open () < 0) {
+			NihError *err;
 
-		err = nih_error_get ();
-		if (err->number != ENOMEM) {
-			nih_warn ("%s: %s", _("Unable to listen for private connections"),
-				  err->message);
+			err = nih_error_get ();
+			if (err->number != ENOMEM) {
+				nih_warn ("%s: %s", _("Unable to listen for private connections"),
+					err->message);
+				nih_free (err);
+				break;
+			}
 			nih_free (err);
-			break;
 		}
-		nih_free (err);
 	}
 
-	/* Open connection to the system bus; we normally expect this to
+	/* Open connection to the appropriate D-Bus bus; we normally expect this to
 	 * fail and will try again later - don't let ENOMEM stop us though.
 	 */
 	while (control_bus_open () < 0) {
@@ -313,21 +372,32 @@
 	}
 
 #ifndef DEBUG
-	/* Now that the startup is complete, send all further logging output
-	 * to kmsg instead of to the console.
-	 */
-	if (system_setup_console (CONSOLE_NONE, FALSE) < 0)
-		nih_free (nih_error_get ());
+	if (use_session_bus == FALSE) {
+		/* Now that the startup is complete, send all further logging output
+		 * to kmsg instead of to the console.
+		 */
+		if (system_setup_console (CONSOLE_NONE, FALSE) < 0)
+			nih_free (nih_error_get ());
 
-	nih_log_set_logger (logger_kmsg);
+		nih_log_set_logger (logger_kmsg);
+	}
 #endif /* DEBUG */
 
 
 	/* Generate and run the startup event or read the state from the
 	 * init daemon that exec'd us
 	 */
-	if (! restart) {
-		NIH_MUST (event_new (NULL, STARTUP_EVENT, NULL));
+	if (! restart ) {
+		if (disable_startup_event) {
+			nih_debug ("Startup event disabled");
+		} else {
+			NIH_MUST (event_new (NULL,
+				initial_event
+				? initial_event
+				: STARTUP_EVENT,
+				NULL));
+		}
+
 	} else {
 		sigset_t mask;
 
@@ -573,3 +643,31 @@
 	}
 }
 #endif /* DEBUG */
+
+/**
+ * handle_confdir:
+ *
+ * Determine where system configuration files should be loaded from.
+ **/
+static void
+handle_confdir (void)
+{
+	char *dir;
+
+	/* user has already specified directory on command-line */
+	if (conf_dir)
+		goto out;
+
+	conf_dir = CONFDIR;
+
+	dir = getenv (CONFDIR_ENV);
+	if (! dir)
+		return;
+
+	conf_dir = dir;
+
+out:
+	nih_debug ("Using alternate configuration directory %s",
+			conf_dir);
+}
+

=== modified file 'init/man/init.5'
--- init/man/init.5	2011-05-12 20:42:28 +0000
+++ init/man/init.5	2011-06-06 15:24:28 +0000
@@ -4,39 +4,76 @@
 init \- Upstart init daemon job configuration
 .\"
 .SH SYNOPSIS
-.B /etc/init
+.B /etc/init/
 .\"
 .SH DESCRIPTION
 On startup, the Upstart
 .BR init (8)
-daemon reads its job configuration from the
-.I /etc/init
-directory, and watches for future changes using
+daemon reads its job configuration from files in the
+.I /etc/init/
+directory, and watches for future changes to these files using
 .BR inotify (7).
 
-Files in this directory must end in
+To be considered by Upstart, files in this directory must have a
+recognized suffix and may also be present in sub-directories.  There are
+two recognized suffixes:
+
+.IP \(bu 4 
+Files ending in
 .I .conf
-and may also be present in sub-directories.
-
-Each file defines a single service or task, with the name taken from its
-relative path within the directory without the extension.  For example a
-job defined in
+are called configuration files, or simply "conf files" for short.
+These are the primary vehicle for specifying a job.
+.IP \(bu 4 
+Files ending in
+.I .override
+are called override files.  If an override file is present, the stanzas
+it contains take precedence over those equivalently named stanzas in the
+corresponding configuration file contents for a particular job.
+The main use for override files is to modify how a job will run without
+having to modify its configuration file directly.  See the section
+\fBOverride File Handling\fP below for further details.
+.P
+A job can thus be defined by either:
+.IP \[bu] 2
+A single configuration file.
+.IP \[bu]
+A single configuration file \fBand\fP a single override file.
+.P
+Unless explicitly stated otherwise, any reference to a jobs
+configuration can refer both to a configuration file or an override
+file.
+
+Each configuration file defines the template for a single \fIservice\fP
+(long-running process or daemon) or \fItask\fP (short-lived process).
+
+Note that a configuration file is not itself a job: it is a description
+of an environmenta job could be run in.  A job is the runtime embodiment
+of a configuration file.
+
+The configuration file name as displayed by Upstart and associated
+tooling is taken from its relative path within the directory without the
+extension.  For example a configuration file
 .I /etc/init/rc-sysinit.conf
 is named
 .IR rc-sysinit ,
-while a job defined in
+while a configuration file
 .I /etc/init/net/apache.conf
 is named
 .IR net/apache .
+Since override files only modify the way a configuration file is
+interpreted, they are not named.
 
-These files are plain text and should not be executable.
+Configuration files are plain text and should not be executable.
 .\"
-.SS Format
+.SS Configuration File Format
 Each line begins with a configuration stanza and continues until either
 the end of the line or a line containing a closing stanza.  Line breaks
 within a stanza are permitted within single or double quotes, or if
 preceeded by a blackslash.
 
+If a stanza is duplicated, the last occurence will be used. Unrecognized
+stanzas will generate parse errors, which will stop a job from running.
+
 Stanzas and their arguments are delimited by whitespace, which consists
 of one or more space or tab characters which are otherwise ignored unless
 placed within single or double quotes.
@@ -69,7 +106,7 @@
 entire command being passed to a shell for expansion.
 
 .nf
-exec /usr/sbin/acpid -c $EVENTSDIR -s $SOCKET
+exec /usr/sbin/acpid \-c $EVENTSDIR \-s $SOCKET
 .fi
 .\"
 .TP
@@ -78,7 +115,7 @@
 be executed using
 .BR sh(1).
 The
-.I -e
+.I \-e
 shell option is always used, so any command that fails will terminate
 the script.
 
@@ -92,7 +129,7 @@
 .nf
 script
     dd bs=1 if=/proc/kmsg of=$KMSGSINK
-    exec /sbin/klogd -P $KMSGSINK
+    exec /sbin/klogd \-P $KMSGSINK
 end script
 .fi
 
@@ -105,14 +142,14 @@
 stanza.
 
 .TP
-.B pre-start exec\fR|\fBscript\fR...
+.B pre\-start exec\fR|\fBscript\fR...
 This process will be run after the job's
 .BR starting (7)
 event has finished, but before the main process is run.  It is typically
 used to prepare the environment, such as making necessary directories.
 .\"
 .TP
-.B post-start exec\fR|\fBscript\fR...
+.B post\-start exec\fR|\fBscript\fR...
 This process will be run before the job's
 .BR started (7)
 event is emitted, but after the main process has been spawned.  It is
@@ -122,7 +159,7 @@
 event until the main process is ready to receive clients.
 .\"
 .TP
-.B pre-stop exec\fR|\fBscript\fR...
+.B pre\-stop exec\fR|\fBscript\fR...
 This process is run if the job is stopped by an event listed in its
 .B stop on
 stanza or by the
@@ -136,7 +173,7 @@
 command without arguments to cancel the stop.
 .\"
 .TP
-.B post-stop exec\fR|\fBscript\fR...
+.B post\-stop exec\fR|\fBscript\fR...
 This process is run after the main process has been killed and before
 the job's
 .BR stopped (7)
@@ -144,19 +181,19 @@
 such as removing temporary directories.
 
 .PP
-All of these processes, including the main process, are optional.  Services
-without a main process will appear to be running until they are stopped,
-this is commonly used to define states such as runlevels.  It's quite
-permissable to have no main process, but to have
+All of these processes, including the main process, are optional.
+Services without a main process will appear to be running until they are
+stopped: this is commonly used to define states such as runlevels.  It
+is permissable to have no main process, but to have
 .B pre-start
 and
-.B post-stop
+.B post\-stop
 processes for the state.
 
 .RS
 .nf
-pre-start exec ifup -a
-post-stop exec ifdown -a
+pre\-start exec ifup \-a
+post\-stop exec ifdown \-a
 .fi
 .RE
 .\"
@@ -238,9 +275,9 @@
 .nf
 start on started gdm or started kdm
 
-start on device-added SUBSYSTEM=tty DEVPATH=ttyS*
+start on device\-added SUBSYSTEM=tty DEVPATH=ttyS*
 
-start on net-device-added INTERFACE!=lo
+start on net\-device\-added INTERFACE!=lo
 .fi
 .TP
 .B stop on \fIEVENT \fR[[\fIKEY=\fR]\fIVALUE\fR]... [\fBand\fR|\fBor\fR...]
@@ -249,7 +286,7 @@
 .B stop on
 stanza defines the set of events that will cause the job to be automatically
 stopped.  It has the same syntax as
-.B start on
+\fBstart on\fP.
 
 .I VALUE
 may additionally expand the value of any variable that came from the
@@ -258,7 +295,7 @@
 .nf
 stop on stopping gdm or stopping kdm
 
-stop on device-removed DEVPATH=$DEVPATH
+stop on device\-removed DEVPATH=$DEVPATH
 .fi
 
 .TP
@@ -284,11 +321,11 @@
 it will not be present if the job was started manually.
 
 In addition, the
-.B pre-stop
+.B pre\-stop
 and
-.B post-stop
+.B post\-stop
 scripts are run with the environment of the events or commands that
-stopped the job.  THe
+stopped the job.  The
 .B UPSTART_STOP_EVENTS
 environment variable contains the list of events that stopped the job,
 it will not be present if the job was stopped manually.
@@ -306,7 +343,8 @@
 .B env \fIKEY\fR[=\fIVALUE\fR]
 Defines a default environment variable, the value of which may be overriden
 by the event or command that starts the job.
-If no value is given, then the value is taken from the
+If \'KEY=VALUE\' is specified, the variable KEY is given the value VALUE.
+If only \'KEY\' is given, then the value is taken from the
 .BR init (8)
 daemon's own environment.
 .\"
@@ -366,7 +404,7 @@
 times in
 .I INTERVAL
 seconds, it will be considered to be having deeper problems and will
-be stopped.
+be stopped. Default COUNT is 10. Default INTERVAL is 5 seconds.
 
 This only applies to automatic respawns and not the
 .BR restart (8)
@@ -385,7 +423,8 @@
 .SS Instances
 By default, only one instance of any job is permitted to exist at one
 time.  Attempting to start a job when it's already starting or running
-results in an error.
+results in an error. Note that a job is considered to be running if its
+pre-start process is running.
 
 Multiple instances may be permitted by defining the names of those
 instances.  If an instance with the same name is not already starting
@@ -405,12 +444,12 @@
 
 .nf
 instance $CONFFILE
-exec /sbin/httpd -c $CONFFILE
+exec /sbin/httpd \-c $CONFFILE
 .fi
 
 .nf
 instance $TTY
-exec /sbin/getty -8 38300 $TTY
+exec /sbin/getty \-8 38300 $TTY
 .fi
 
 These jobs appear in the
@@ -461,6 +500,11 @@
 
 This stanza allows a job to document in its job configuration what events
 it emits itself, and may be useful for graphing possible transitions.
+
+The
+.BR initctl "(8) " check\-config
+command attempts to use this stanza to resolve events.
+
 .\"
 .SS Process environment
 Many common adjustments to the process environment, such as resource
@@ -481,7 +525,7 @@
 is special, it not only connects the job to the system console but sets
 the job to be the owner of the system console, which means it will receive
 certain signals from the kernel when special key combinations such as
-Control-C are pressed.
+Control\-C are pressed.
 .\"
 .TP
 .B umask \fIUMASK
@@ -561,6 +605,46 @@
 .B unlimited
 may be specified for either.
 .\"
+.SS Override File Handling
+Override files allow a jobs environment to be changed without modifying
+the jobs configuration file. Rules governing override files:
+
+.IP \[bu] 2
+If a job is embodied with only a configuration file, the contents of
+this file define the job.
+.IP \[bu]
+If an override files exists where there is no existing cofiguration
+file, the override file is ignored.
+.IP \[bu]
+If both a configuration file \fBand\fP an override file exist for a job
+and both files are syntactically correct:
+.RS
+.IP \[bu] 2
+stanzas in the override file will take precedence over stanzas present
+in the corresponding configuration file.
+.IP \[bu]
+stanzas in the override file which are not present in the corresponding
+configuration file will be honoured when the job runs.
+.RE
+.IP \[bu]
+If both a configuration file and an override file exist for a job and
+subsequently the override file is deleted, the configuration file is
+automatically reloaded with the effect that any changes introduced by
+the override file are undone and the configuration file alone now defines
+the job.
+.IP \[bu]
+If both a configuration file and an override file exist for a job and
+subsequently the configuration file is deleted, a new instance of the
+job can no longer be started (since without a corresponding
+configuration file an override file is ignored).
+.IP \[bu]
+If both a configuration file and an override file exist for a job and
+any of the contents of the override file are invalid, the override file
+is ignored and only the contents of the configuration file are
+considered.
+.P
+
+.\"
 .SS Miscellaneous
 .TP
 .B kill signal \fISIGNAL
@@ -578,7 +662,7 @@
 Specifies the interval between sending the job's main process the
 "stopping" (see above) and
 .I SIGKILL
-signals when stopping the running job.
+signals when stopping the running job. Default is 5 seconds.
 .\"
 .TP
 .B expect stop
@@ -586,7 +670,7 @@
 .I SIGSTOP
 signal to indicate that it is ready.
 .BR init (8)
-will wait for this signal before running the job's post-start script,
+will wait for this signal before running the job's post\-start script,
 or considering the job to be running.
 
 .BR init (8)
@@ -600,7 +684,7 @@
 after being run.
 .BR init (8)
 will follow this daemonisation, and will wait for this to occur before
-running the job's post-start script or considering the job to be running.
+running the job's post\-start script or considering the job to be running.
 
 Without this stanza
 .BR init (8)
@@ -612,13 +696,55 @@
 Specifies that the job's main process will fork once after being run.
 .BR init (8)
 will follow this fork, and will wait for this to occur before
-running the job's post-start script or considering the job to be running.
+running the job's post\-start script or considering the job to be running.
 
 Without this stanza
 .BR init (8)
 is unable to supervise forking processes and will believe them to have
 stopped as soon as they fork on startup.
 .\"
+.SH BUGS
+The 
+.B and
+and 
+.B or
+operators allowed with
+.B start on
+and
+.B stop on
+do not work intuitively: operands to the right of either operator are
+only evaluated once and state information is then discarded. This can
+lead to jobs with complex \fBstart on\fP or \fPstop on\fP conditions
+not behaving as expected \fIwhen restarted\fP. For example, if a job
+encodes the following condition:
+.ti +4
+.sp 1
+.nf
+start on A and (B or C)
+.fi
+
+When 'A' and 'B' become true, the condition is satisfied so the job will
+be run. However, if the job ends and subsequently 'A' and 'C' become true,
+the job will \fInot\fP be re-run even though the condtion is satisfied.
+Avoid using complex conditions with jobs which need to be restarted.
+.\"
+.SH AUTHOR
+Manual page written by Scott James Remnant
+.RB < [e-mail] >
+and James Hunt
+.RB < [e-mail] > .
+.\"
+.SH REPORTING BUGS
+Report bugs at
+.RB < https://launchpad.net/upstart/+bugs >
+.\"
+.SH COPYRIGHT
+Copyright \(co 2009-2011 Canonical Ltd.
+.br
+This is free software; see the source for copying conditions.  There is NO
+warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+.\"
 .SH SEE ALSO
 .BR init (8)
 .BR sh (1)

=== modified file 'init/man/init.8'
--- init/man/init.8	2010-02-04 19:26:17 +0000
+++ init/man/init.8	2011-06-06 15:24:28 +0000
@@ -1,4 +1,4 @@
-.TH init 8 2010-02-04 "Upstart"
+.TH init 8 2011-04-06 "Upstart"
 .\"
 .SH NAME
 init \- Upstart process management daemon
@@ -64,7 +64,32 @@
 by placing them on the kernel command-line.
 .\"
 .TP
-.B --verbose
+.B \-\-confdir \fIdirectory\fP
+Read job configuration files from a directory other than
+\fI/etc/init\fP.
+.\"
+.TP
+.B \-\-no\-sessions
+Disable user and chroot sessions.
+.\"
+.TP
+.B \-\-no\-startup\-event
+Suppress emission of the initial startup event. This option should only
+be used for testing since it will stop the 
+.BR init (8)
+daemon from starting \fBany\fP jobs automatically.
+.\"
+.TP
+.B \-\-session
+Connect to the D\-Bus session bus. This should only be used for testing.
+.\"
+.TP
+.B \-\-startup-event \fIevent\fP
+Specify a different initial startup event from the standard
+.BR startup (7) .
+.\"
+.TP
+.B \-\-verbose
 Outputs verbose messages about job state changes and event emissions to the
 system console or log, useful for debugging boot.
 .\"
@@ -90,18 +115,19 @@
 .RB < https://launchpad.net/upstart/+bugs >
 .\"
 .SH COPYRIGHT
-Copyright \(co 2010 Canonical Ltd.
+Copyright \(co 2009\-2011 Canonical Ltd.
 .br
 This is free software; see the source for copying conditions.  There is NO
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 .\"
 .SH SEE ALSO
+.BR control-alt-delete (7)
 .BR init (5)
 .BR initctl (8)
-.BR telinit (8)
 .BR runlevel (7)
 .BR startup (7)
 .BR starting (7)
 .BR started (7)
 .BR stopping (7)
 .BR stopped (7)
+.BR telinit (8)

=== modified file 'init/parse_conf.c'
--- init/parse_conf.c	2009-06-23 09:29:35 +0000
+++ init/parse_conf.c	2011-06-06 15:24:28 +0000
@@ -74,6 +74,12 @@
 	nih_assert (file != NULL);
 	nih_assert (pos != NULL);
 
+	/* If we update 'stanzas' to allow content in init.conf, this
+	 * function must be updated in a similar manner to parse_job()
+	 * to handle overrides files.
+	 */
+	nih_assert (sizeof(stanzas) / sizeof(stanzas[0]) == 1);
+
 	if (nih_config_parse_file (file, len, pos, lineno,
 				   stanzas, conffile) < 0)
 		return -1;

=== modified file 'init/parse_job.c'
--- init/parse_job.c	2011-05-12 20:42:28 +0000
+++ init/parse_job.c	2011-06-06 15:24:28 +0000
@@ -2,7 +2,7 @@
  *
  * parse_job.c - job definition parsing
  *
- * Copyright © 2010 Canonical Ltd.
+ * Copyright © 2010,2011 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -263,6 +263,8 @@
 /**
  * parse_job:
  * @parent: parent object for new job,
+ * @session: session,
+ * @update: If not NULL, update the existing specified JobClass,
  * @name: name of new job,
  * @file: file or string to parse,
  * @len: length of @file,
@@ -278,10 +280,13 @@
  * of the returned job are freed, the returned job will also be
  * freed.
  *
- * Returns: new JobClass structure on success, NULL on raised error.
+ * Returns: if @update is NULL, returns new JobClass structure on success, NULL on raised error.
+ * If @update is not NULL, returns @update or NULL on error.
  **/
 JobClass *
 parse_job (const void *parent,
+	   Session    *session,
+	   JobClass   *update,
 	   const char *name,
 	   const char *file,
 	   size_t      len,
@@ -294,13 +299,22 @@
 	nih_assert (file != NULL);
 	nih_assert (pos != NULL);
 
-	class = job_class_new (parent, name);
-	if (! class)
-		nih_return_system_error (NULL);
+	if (update) {
+		class = update;
+		nih_debug ("Reusing JobClass %s (%s)",
+				class->name, class->path);
+	} else {
+		nih_debug ("Creating new JobClass %s",
+			  name);
+		class = job_class_new (parent, name, session);
+		if (! class)
+			nih_return_system_error (NULL);
+	}
 
 	if (nih_config_parse_file (file, len, pos, lineno,
-				   stanzas, class) < 0) {
-		nih_free (class);
+				stanzas, class) < 0) {
+		if (!update)
+			nih_free (class);
 		return NULL;
 	}
 

=== modified file 'init/parse_job.h'
--- init/parse_job.h	2009-06-23 09:29:35 +0000
+++ init/parse_job.h	2011-06-06 15:24:28 +0000
@@ -1,6 +1,6 @@
 /* upstart
  *
- * Copyright © 2009 Canonical Ltd.
+ * Copyright © 2010 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -22,12 +22,14 @@
 
 #include <nih/macros.h>
 
+#include "session.h"
 #include "job_class.h"
 
 
 NIH_BEGIN_EXTERN
 
-JobClass *parse_job (const void *parent, const char *name,
+JobClass *parse_job (const void *parent, Session *session,
+		     JobClass *update, const char *name,
 		     const char *file, size_t len,
 		     size_t *pos, size_t *lineno)
 	__attribute__ ((warn_unused_result, malloc));

=== modified file 'init/paths.h'
--- init/paths.h	2010-02-26 15:27:14 +0000
+++ init/paths.h	2011-06-06 15:24:28 +0000
@@ -1,6 +1,6 @@
 /* upstart
  *
- * Copyright © 2010 Canonical Ltd.
+ * Copyright © 2010-2011 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
  * This program is free software; you can redistribute it and/or modify
@@ -67,12 +67,35 @@
 /**
  * CONFDIR:
  *
- * Top-level directory of the system configuration files.
+ * Default top-level directory of the system configuration files.
  **/
 #ifndef CONFDIR
 #define CONFDIR "/etc/init"
 #endif
 
+/**
+ * USERCONFDIR:
+ *
+ * Sub-directory of user's home directory for their jobs.
+ **/
+#ifndef USERCONFDIR
+#define USERCONFDIR ".init"
+#endif
+
+
+/**
+ * CONFDIR_ENV:
+ *
+ * If this environment variable is set, read configuration files
+ * from the location specified, rather than CONFDIR.
+ *
+ * Value is expected to be the full path to an alternative job
+ * configuration directory.
+ **/
+#ifndef CONFDIR_ENV
+#define CONFDIR_ENV "UPSTART_CONFDIR"
+#endif
+
 
 /**
  * SHELL:
@@ -103,5 +126,55 @@
 #define TELINIT SBINDIR "/telinit"
 #endif
 
+/**
+ * File extension for standard configuration files.
+ **/
+#define CONF_EXT_STD ".conf"
+
+/**
+ * File extension for override files.
+ *
+ * Note that override files are not stored in the ConfSource 'files' hash:
+ * all JobClass information from override files is added to the JobClass for
+ * the corresponding (CONF_EXT_STD) object.
+ **/
+#define CONF_EXT_OVERRIDE ".override"
+
+/**
+ * Determine if specified path extension representes a standard
+ * configuration file.
+ *
+ * @period: pointer to last period in path to check.
+ *
+ * Returns 1 if specified path extension matches that for a
+ * standard configuration file, else return 0.
+ **/
+#define IS_CONF_EXT_STD(period) \
+	(!strcmp (period, CONF_EXT_STD))
+
+/**
+ * Determine if specified path extension representes an
+ * override file.
+ *
+ * @period: pointer to last period in path to check.
+ *
+ * Returns 1 if specified path extension matches that for
+ * an override file, else return 0.
+ **/
+#define IS_CONF_EXT_OVERRIDE(period) \
+	(!strcmp (period, CONF_EXT_OVERRIDE))
+
+/**
+ * Determine if specified filename has a valid configuration
+ * file name extension.
+ *
+ * @period: pointer to last period in filename.
+ *
+ * Returns: TRUE if extension beyond @period is one of the
+ * recognized types, else FALSE.
+ **/
+#define IS_CONF_EXT(period) \
+	(IS_CONF_EXT_STD(period) || \
+	 IS_CONF_EXT_OVERRIDE(period))
 
 #endif /* INIT_PATHS_H */

=== added file 'init/session.c'
--- init/session.c	1970-01-01 00:00:00 +0000
+++ init/session.c	2011-06-06 15:24:28 +0000
@@ -0,0 +1,279 @@
+/* upstart
+ *
+ * session.c - session segregation
+ *
+ * Copyright © 2010,2011 Canonical Ltd.
+ * Author: Scott James Remnant <[e-mail]>.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif /* HAVE_CONFIG_H */
+
+
+#include <dbus/dbus.h>
+
+#include <sys/types.h>
+
+#include <pwd.h>
+#include <errno.h>
+#include <limits.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <nih/macros.h>
+#include <nih/alloc.h>
+#include <nih/list.h>
+#include <nih/string.h>
+#include <nih/logging.h>
+#include <nih/error.h>
+
+#include <nih-dbus/dbus_message.h>
+
+#include "session.h"
+#include "conf.h"
+#include "paths.h"
+
+
+/**
+ * sessions:
+ *
+ * This list holds the list of known sessions; each item is a Session
+ * structure.
+ **/
+NihList *sessions = NULL;
+
+/**
+ * disable_sessions:
+ *
+ * If TRUE, disable user and chroot sessions, resulting in a
+ * "traditional" (pre-session support) system.
+ **/
+int disable_sessions = FALSE;
+
+
+/* Prototypes for static functions */
+static void session_create_conf_source (Session *sesson);
+
+
+/**
+ * session_init:
+ *
+ * Initialise the sessions list.
+ **/
+void
+session_init (void)
+{
+	if (! sessions)
+		sessions = NIH_MUST (nih_list_new (NULL));
+}
+
+
+Session *
+session_new (const void *parent,
+	     const char *chroot,
+	     uid_t       user)
+{
+	Session *session;
+
+	nih_assert ((chroot != NULL) || (user != 0));
+
+	session_init ();
+
+	session = nih_new (parent, Session);
+	if (! session)
+		return NULL;
+
+	nih_list_init (&session->entry);
+
+	if (chroot) {
+		session->chroot = nih_strdup (session, chroot);
+		if (! session->chroot) {
+			nih_free (session);
+			return NULL;
+		}
+	} else {
+		session->chroot = NULL;
+	}
+
+	session->user = user;
+
+	session->conf_path = NULL;
+
+	nih_alloc_set_destructor (session, nih_list_destroy);
+
+	nih_list_add (sessions, &session->entry);
+
+	return session;
+}
+
+Session *
+session_from_dbus (const void     *parent,
+		   NihDBusMessage *message)
+{
+	const char   *sender;
+	DBusError     dbus_error;
+	unsigned long unix_user;
+	unsigned long unix_process_id;
+	char          root[PATH_MAX];
+	Session      *session;
+
+	nih_assert (message != NULL);
+
+	/* Handle explicit command-line request and alternative request
+	 * method (primarily for test framework) to disable session support.
+	 */
+	if (disable_sessions || getenv ("UPSTART_NO_SESSIONS"))
+		return NULL;
+
+	session_init ();
+
+	/* Ask D-Bus nicely for the origin uid and/or pid of the caller;
+	 * sadly we can't ask the bus daemon for the origin pid, so that
+	 * one will just have to stay user-session only.
+	 */
+	dbus_error_init (&dbus_error);
+
+	sender = dbus_message_get_sender (message->message);
+	if (sender) {
+		unix_user = dbus_bus_get_unix_user (message->connection, sender,
+						    &dbus_error);
+		if (unix_user == (unsigned long)-1) {
+			dbus_error_free (&dbus_error);
+			unix_user = 0;
+		}
+
+		unix_process_id = 0;
+
+	} else {
+		if (! dbus_connection_get_unix_user (message->connection,
+						     &unix_user))
+			unix_process_id = 0;
+
+		if (! dbus_connection_get_unix_process_id (message->connection,
+							   &unix_process_id))
+			unix_process_id = 0;
+	}
+
+	/* If we retrieved a process id, look up the root path for it;
+	 * if it's just '/' don't worry so much about it.
+	 */
+	if (unix_process_id) {
+		nih_local char *symlink = NULL;
+		ssize_t len;
+
+		symlink = NIH_MUST (nih_sprintf (NULL, "/proc/%lu/root",
+						 unix_process_id));
+		len = readlink (symlink, root, sizeof root);
+		if (len < 0)
+			return NULL;
+
+		root[len] = '\0';
+
+		if (! strcmp (root, "/")) {
+			unix_process_id = 0;
+			if (! unix_user)
+				return NULL;
+		}
+
+	} else if (! unix_user) {
+		/* No process id or user id found, return the NULL session */
+		return NULL;
+
+	}
+
+	/* Now find in the existing Sessions list */
+	NIH_LIST_FOREACH (sessions, iter) {
+		Session *session = (Session *)iter;
+
+		if (unix_process_id) {
+			if (! session->chroot)
+				continue;
+
+			/* ignore sessions relating to other chroots */
+			if (strcmp (session->chroot, root))
+				continue;
+		}
+
+		/* ignore sessions relating to other users */
+		if (unix_user != session->user)
+			continue;
+
+		if (! session->conf_path)
+			session_create_conf_source (session);
+
+		return session;
+	}
+
+
+	/* Didn't find one, make a new one */
+	session = NIH_MUST (session_new (parent, unix_process_id ? root : NULL,
+					 unix_user));
+	session_create_conf_source (session);
+
+	return session;
+}
+
+static void
+session_create_conf_source (Session *session)
+{
+	ConfSource *source;
+
+	nih_assert (session != NULL);
+	nih_assert (session->conf_path == NULL);
+
+	if (session->chroot)
+		session->conf_path = NIH_MUST (nih_strdup (NULL, session->chroot));
+	if (session->user) {
+		struct passwd *pwd;
+
+		pwd = getpwuid (session->user);
+		if (! pwd) {
+			nih_error ("%d: %s: %s", session->user,
+				   _("Unable to lookup home directory"),
+				   strerror (errno));
+
+			nih_free (session->conf_path);
+			session->conf_path = NULL;
+			return;
+		}
+
+		NIH_MUST (nih_strcat_sprintf (&session->conf_path, NULL, "%s/%s",
+					      pwd->pw_dir, USERCONFDIR));
+	} else {
+		NIH_MUST (nih_strcat (&session->conf_path, NULL, CONFDIR));
+	}
+
+	source = NIH_MUST (conf_source_new (session, session->conf_path,
+					    CONF_JOB_DIR));
+	source->session = session;
+
+	if (conf_source_reload (source) < 0) {
+		NihError *err;
+
+		err = nih_error_get ();
+		if (err->number != ENOENT)
+			nih_error ("%s: %s: %s", source->path,
+				   _("Unable to load configuration"),
+				   err->message);
+		nih_free (err);
+
+		nih_free (source);
+		nih_free (session->conf_path);
+		session->conf_path = NULL;
+		return;
+	}
+}

=== added file 'init/session.h'
--- init/session.h	1970-01-01 00:00:00 +0000
+++ init/session.h	2011-06-06 15:24:28 +0000
@@ -0,0 +1,87 @@
+/* upstart
+ *
+ * Copyright © 2010,2011 Canonical Ltd.
+ * Author: Scott James Remnant <[e-mail]>.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef INIT_SESSION_H
+#define INIT_SESSION_H
+
+#include <sys/types.h>
+
+#include <nih/macros.h>
+#include <nih/list.h>
+
+#include <nih-dbus/dbus_message.h>
+
+
+/**
+ * Session:
+ * @entry: list header,
+ * @chroot: path all jobs are chrooted to,
+ * @user: uid all jobs are switched to,
+ * @conf_path: configuration path.
+ *
+ * This structure is used to identify collections of jobs
+ * that share either a common @chroot and/or common @user.
+ *
+ * Summary of Session values for different environments:
+ *
+ * +-------------+---------------------------------------+
+ * |    D-Bus    |             Session                   |
+ * +------+------+--------+-----+------------------------+
+ * | user | PID  | chroot | uid | Object contents        |
+ * +------+------+--------+-----+------------------------+
+ * | 0    | >0   | no     | 0   | NULL (*1)              |
+ * | >0   | "0"  | no     | >0  | only uid set.          |
+ * | 0    | >0   | yes    | 0   | chroot + conf_path set |
+ * | >0   | ??   | yes    | >0  | XXX: fails (*2)        |
+ * +------+------+--------+-----+------------------------+
+ *
+ * Notes:
+ *
+ * (*1) - The "NULL session" represents the "traditional" environment
+ * before sessions were introduced (namely a non-chroot environment
+ * where all job and event operations were handled by uid 0 (root)).
+ *
+ * (*2) - error is:
+ *
+ *   initctl: Unable to connect to system bus: Failed to connect to socket
+ *   /var/run/dbus/system_bus_socket: No such file or directory
+ * 
+ **/
+typedef struct session {
+	NihList entry;
+	char *  chroot;
+	uid_t   user;
+	char *  conf_path;
+} Session;
+
+
+NIH_BEGIN_EXTERN
+
+extern NihList *sessions;
+
+void     session_init      (void);
+
+Session *session_new       (const void *parent, const char *chroot, uid_t user)
+	__attribute__ ((malloc, warn_unused_result));
+
+Session *session_from_dbus (const void *parent, NihDBusMessage *message);
+
+NIH_END_EXTERN
+
+#endif /* INIT_SESSION_H */

=== modified file 'init/tests/test_blocked.c'
--- init/tests/test_blocked.c	2009-06-23 09:29:35 +0000
+++ init/tests/test_blocked.c	2011-06-06 15:24:28 +0000
@@ -46,7 +46,7 @@
 	 * in a list.
 	 */
 	TEST_FEATURE ("with job");
-	class = job_class_new (NULL, "test");
+	class = job_class_new (NULL, "test", NULL);
 	job = job_new (class, "");
 
 	TEST_ALLOC_FAIL {
@@ -364,6 +364,9 @@
 main (int   argc,
       char *argv[])
 {
+	/* run tests in legacy (pre-session support) mode */
+	setenv ("UPSTART_NO_SESSIONS", "1", 1);
+
 	test_new ();
 
 	return 0;

=== modified file 'init/tests/test_conf.c'
--- init/tests/test_conf.c	2011-02-17 23:38:17 +0000
+++ init/tests/test_conf.c	2011-06-06 15:24:28 +0000
@@ -2,7 +2,6 @@
  *
  * test_conf.c - test suite for init/conf.c
  *
- * Copyright © 2011 Google Inc.
  * Copyright © 2009 Canonical Ltd.
  * Author: Scott James Remnant <[e-mail]>.
  *
@@ -47,6 +46,50 @@
 #include "job.h"
 #include "conf.h"
 
+/* macro to try and ensure the environment is as pristine as possible
+ * (to avoid follow-on errors caused by not freeing objects in a
+ * previous test, say)
+ */
+#define TEST_ENSURE_CLEAN_ENV()                                      \
+{                                                                    \
+	setvbuf(stdout, NULL, _IONBF, 0);                            \
+                                                                     \
+	if (job_classes) {                                           \
+		TEST_HASH_EMPTY (job_classes);                       \
+	}                                                            \
+                                                                     \
+	if (conf_sources) {                                          \
+		TEST_LIST_EMPTY (conf_sources);                      \
+	}                                                            \
+                                                                     \
+	if (nih_io_watches) {                                        \
+		TEST_LIST_EMPTY (nih_io_watches);                    \
+	}                                                            \
+                                                                     \
+	if (nih_timers) {                                            \
+		TEST_LIST_EMPTY (nih_timers);                        \
+	}                                                            \
+                                                                     \
+	if (events) {                                                \
+		TEST_LIST_EMPTY (events);                            \
+	}                                                            \
+}
+
+/* Force an inotify watch update */
+#define TEST_FORCE_WATCH_UPDATE()                                    \
+{                                                                    \
+	int         nfds = 0;                                        \
+	fd_set      readfds, writefds, exceptfds;                    \
+	                                                             \
+	FD_ZERO (&readfds);                                          \
+	FD_ZERO (&writefds);                                         \
+	FD_ZERO (&exceptfds);                                        \
+	                                                             \
+	nih_debug("calling nih_io_select_fds");                      \
+	nih_io_select_fds (&nfds, &readfds, &writefds, &exceptfds);  \
+	nih_debug("calling nih_io_handle_fds");                      \
+	nih_io_handle_fds (&readfds, &writefds, &exceptfds);         \
+}
 
 void
 test_source_new (void)
@@ -2417,6 +2460,1255 @@
 	}
 }
 
+void
+test_toggle_conf_name (void)
+{
+	char override_ext[] = ".override";
+	char dirname[PATH_MAX];
+	char filename[PATH_MAX];
+	JobClass *job;
+	char *f;
+	char *p;
+
+	TEST_FUNCTION_FEATURE ("toggle_conf_name",
+			"changing conf to override");
+
+	TEST_FILENAME (dirname);
+	strcpy (filename, dirname);
+	strcat (filename, "/foo.conf");
+	f = toggle_conf_name (NULL, filename);
+	TEST_NE_P (f, NULL);
+
+	p = strstr (f, ".override");
+	TEST_NE_P (p, NULL);
+	TEST_EQ_P (p, f+strlen (f) - strlen (override_ext));
+	nih_free (f);
+
+	TEST_FEATURE ("changing override to conf");
+	strcpy (filename, dirname);
+	strcat (filename, "/bar.override");
+	f = toggle_conf_name (NULL, filename);
+	TEST_NE_P (f, NULL);
+
+	p = strstr (f, ".conf");
+	TEST_NE_P (p, NULL);
+	TEST_EQ_P (p, f+strlen (f) - strlen (".conf"));
+	nih_free (f);
+
+	/* test parent param */
+	job = job_class_new (NULL, "foo", NULL);
+	TEST_NE_P (job, NULL);
+
+	f = toggle_conf_name (job, filename);
+	TEST_NE_P (f, NULL);
+
+	TEST_EQ (TRUE, nih_alloc_parent (f, job));
+
+	nih_free (job);
+}
+
+void
+test_override (void)
+{
+	ConfSource *source;
+	ConfFile   *file;
+	FILE       *f;
+	int         ret, fd[4096], i = 0;
+	char        dirname[PATH_MAX];
+	char        filename[PATH_MAX], override[PATH_MAX];
+	JobClass   *job;
+	NihError   *err;
+
+	program_name = "test";
+	nih_log_set_priority (NIH_LOG_FATAL);
+
+	TEST_ENSURE_CLEAN_ENV ();
+	TEST_GROUP ("override files");
+
+	/* Make sure that we have inotify before performing some tests... */
+	if ((fd[0] = inotify_init ()) < 0) {
+		printf ("SKIP: inotify not available\n");
+		goto no_inotify;
+	}
+	close (fd[0]);
+
+
+	/* Explicit test of behaviour prior to introduction of override files.
+	 * 
+	 * conf with no override before watch:
+	 *   create conf
+	 *   create watch
+	 *   ensure conf loaded
+	 *   update conf
+	 *   ensure conf updated
+	 *   delete conf
+	 *   ensure conf deleted
+	 */
+	TEST_FEATURE ("with pre-override environment (conf with no override before watch)");
+	TEST_ENSURE_CLEAN_ENV ();
+	TEST_FILENAME (dirname);
+	TEST_EQ (mkdir (dirname, 0755), 0);
+
+	/* create conf */
+	strcpy (filename, dirname);
+	strcat (filename, "/foo.conf");
+	f = fopen (filename, "w");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "start on started\n");
+	fprintf (f, "emits hello\n");
+	fclose (f);
+
+	/* create watch */
+	source = conf_source_new (NULL, dirname, CONF_JOB_DIR);
+	TEST_NE_P (source, NULL);
+	ret = conf_source_reload (source);
+	TEST_EQ (ret, 0);
+
+	/* ensure conf loaded */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_NE_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_EQ_P (file->job, job);
+	TEST_EQ_STR ((job->emits)[0], "hello");
+	TEST_NE_P (job->start_on, NULL);
+
+	/* update conf */
+	f = fopen (filename, "a");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "manual\n");
+	fclose (f);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf updated */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_NE_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_EQ_P (job->start_on, NULL);
+
+	/* delete conf */
+	unlink (filename);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_EQ_P (job, NULL);
+	TEST_HASH_EMPTY (job_classes);
+	TEST_HASH_EMPTY (source->files);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf deleted */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_EQ_P (file, NULL);
+
+	nih_free (source);
+	TEST_EQ (rmdir (dirname), 0);
+
+
+	/* Explicit test of behaviour prior to introduction of override files.
+	 * 
+	 * conf with no override after watch:
+	 *   create watch
+	 *   create conf
+	 *   ensure conf loaded
+	 *   update conf
+	 *   ensure conf updated
+	 *   delete conf
+	 *   ensure conf deleted
+	 */
+	TEST_ENSURE_CLEAN_ENV ();
+	TEST_FEATURE ("with pre-override environment (conf with no override after watch)");
+	TEST_FILENAME (dirname);
+	TEST_EQ (mkdir (dirname, 0755), 0);
+
+	/* create watch */
+	source = conf_source_new (NULL, dirname, CONF_JOB_DIR);
+	TEST_NE_P (source, NULL);
+	ret = conf_source_reload (source);
+	TEST_EQ (ret, 0);
+
+	/* create conf */
+	strcpy (filename, dirname);
+	strcat (filename, "/foo.conf");
+	f = fopen (filename, "w");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "start on started\n");
+	fprintf (f, "emits hello\n");
+	fclose (f);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf loaded */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_NE_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_EQ_P (file->job, job);
+	TEST_EQ_STR ((job->emits)[0], "hello");
+
+	/* update conf */
+	f = fopen (filename, "a");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "manual\n");
+	fclose (f);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf updated */
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_EQ_P (job->start_on, NULL);
+
+	/* delete conf */
+	unlink (filename);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf deleted */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_EQ_P (file, NULL);
+	nih_free (source);
+	TEST_EQ (rmdir (dirname), 0);
+
+
+	TEST_FEATURE ("ensure lone override ignored before watch");
+	TEST_ENSURE_CLEAN_ENV ();
+	TEST_FILENAME (dirname);
+	TEST_EQ (mkdir (dirname, 0755), 0);
+
+	/* create override */
+	strcpy (filename, dirname);
+	strcat (filename, "/foo.override");
+	f = fopen (filename, "w");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "manual\n");
+	fclose (f);
+
+	/* create watch */
+	source = conf_source_new (NULL, dirname, CONF_JOB_DIR);
+	TEST_NE_P (source, NULL);
+	ret = conf_source_reload (source);
+	TEST_EQ (ret, 0);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure no conf object created */
+	TEST_HASH_EMPTY (source->files);
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_EQ_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_EQ_P (job, NULL);
+
+	/* update override */
+	f = fopen (filename, "a");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "author \"me\"\n");
+	fclose (f);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure no conf object created */
+	TEST_HASH_EMPTY (source->files);
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_EQ_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_EQ_P (job, NULL);
+
+	/* delete override */
+	unlink (filename);
+	nih_free (source);
+	TEST_EQ (rmdir (dirname), 0);
+
+
+	TEST_FEATURE ("ensure lone override ignored after watch");
+	TEST_ENSURE_CLEAN_ENV ();
+	TEST_FILENAME (dirname);
+	TEST_EQ (mkdir (dirname, 0755), 0);
+
+	/* create watch */
+	source = conf_source_new (NULL, dirname, CONF_JOB_DIR);
+	TEST_NE_P (source, NULL);
+	ret = conf_source_reload (source);
+	TEST_EQ (ret, 0);
+
+	strcpy (filename, dirname);
+	strcat (filename, "/bar.override");
+	f = fopen (filename, "w");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "manual\n");
+	fclose (f);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure no conf object created */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_EQ_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "bar");
+	TEST_EQ_P (job, NULL);
+
+	/* delete override */
+	unlink (filename);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure override still not present */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_EQ_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "bar");
+	TEST_EQ_P (job, NULL);
+
+	nih_free (source);
+	TEST_EQ (rmdir (dirname), 0);
+
+
+	TEST_FEATURE ("create conf, watch, then create/modify/delete override");
+	TEST_ENSURE_CLEAN_ENV ();
+	TEST_FILENAME (dirname);
+	TEST_EQ (mkdir (dirname, 0755), 0);
+
+	/* create conf */
+	strcpy (filename, dirname);
+	strcat (filename, "/foo.conf");
+	f = fopen (filename, "w");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "start on started\n");
+	fprintf (f, "emits hello\n");
+	fclose (f);
+
+	/* create watch */
+	source = conf_source_new (NULL, dirname, CONF_JOB_DIR);
+	TEST_NE_P (source, NULL);
+	ret = conf_source_reload (source);
+	TEST_EQ (ret, 0);
+
+	/* ensure conf loaded */
+	TEST_HASH_NOT_EMPTY (source->files);
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_NE_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_EQ_P (file->job, job);
+	TEST_EQ_STR ((job->emits)[0], "hello");
+	TEST_EQ_P ((job->emits)[1], NULL);
+	TEST_NE_P (job->start_on, NULL);
+
+	/* create override */
+	strcpy (override, dirname);
+	strcat (override, "/foo.override");
+	f = fopen (override, "w");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "manual\n");
+	fclose (f);
+
+	TEST_HASH_NOT_EMPTY (source->files);
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf updated */
+	TEST_HASH_NOT_EMPTY (source->files);
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_NE_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_EQ_P (job->start_on, NULL);
+
+	/* ensure no override in hash */
+	file = (ConfFile *)nih_hash_lookup (source->files, override);
+	TEST_EQ_P (file, NULL);
+
+	/* modify override */
+	f = fopen (override, "a");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "emits world\n");
+	fclose (f);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf updated */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_NE_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_EQ_P (job->start_on, NULL);
+	TEST_EQ_STR ((job->emits)[0], "hello");
+	TEST_EQ_STR ((job->emits)[1], "world");
+
+	/* delete override */
+	unlink (override);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf reverted */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_NE_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_NE_P (job->start_on, NULL);
+	TEST_EQ_STR ((job->emits)[0], "hello");
+	TEST_EQ_P ((job->emits)[1], NULL);
+
+	nih_free (source);
+	unlink (filename);
+	TEST_EQ (rmdir (dirname), 0);
+
+
+	TEST_FEATURE ("create watch, conf, then create/modify/delete override");
+	TEST_ENSURE_CLEAN_ENV ();
+	TEST_FILENAME (dirname);
+	TEST_EQ (mkdir (dirname, 0755), 0);
+
+	/* create watch */
+	source = conf_source_new (NULL, dirname, CONF_JOB_DIR);
+	TEST_NE_P (source, NULL);
+	ret = conf_source_reload (source);
+	TEST_EQ (ret, 0);
+
+	/* create conf */
+	strcpy (filename, dirname);
+	strcat (filename, "/foo.conf");
+	f = fopen (filename, "w");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "start on started\n");
+	fprintf (f, "emits hello\n");
+	fclose (f);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf loaded */
+	TEST_HASH_NOT_EMPTY (source->files);
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_NE_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_EQ_P (file->job, job);
+	TEST_EQ_STR ((job->emits)[0], "hello");
+	TEST_EQ_P ((job->emits)[1], NULL);
+	TEST_NE_P (job->start_on, NULL);
+
+	/* create override */
+	strcpy (override, dirname);
+	strcat (override, "/foo.override");
+	f = fopen (override, "w");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "manual\n");
+	fclose (f);
+
+	TEST_HASH_NOT_EMPTY (source->files);
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf updated */
+	TEST_HASH_NOT_EMPTY (source->files);
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_NE_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_EQ_P (job->start_on, NULL);
+
+	/* ensure no override in hash */
+	file = (ConfFile *)nih_hash_lookup (source->files, override);
+	TEST_EQ_P (file, NULL);
+
+	/* modify override */
+	f = fopen (override, "a");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "emits world\n");
+	fclose (f);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf updated */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_NE_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_EQ_P (job->start_on, NULL);
+	TEST_EQ_STR ((job->emits)[0], "hello");
+	TEST_EQ_STR ((job->emits)[1], "world");
+
+	/* delete override */
+	unlink (override);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf reverted */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_NE_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_NE_P (job->start_on, NULL);
+	TEST_EQ_STR ((job->emits)[0], "hello");
+	TEST_EQ_P ((job->emits)[1], NULL);
+
+	nih_free (source);
+	unlink (filename);
+	TEST_EQ (rmdir (dirname), 0);
+
+
+	TEST_FEATURE ("create override, watch, then create/modify/delete conf");
+	TEST_ENSURE_CLEAN_ENV ();
+	TEST_FILENAME (dirname);
+	TEST_EQ (mkdir (dirname, 0755), 0);
+
+	strcpy (filename, dirname);
+	strcat (filename, "/foo.conf");
+	strcpy (override, dirname);
+	strcat (override, "/foo.override");
+
+	/* create override */
+	f = fopen (override, "w");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "manual\n");
+	fprintf (f, "author \"bar\"\n");
+	fclose (f);
+
+	/* create watch */
+	source = conf_source_new (NULL, dirname, CONF_JOB_DIR);
+	TEST_NE_P (source, NULL);
+	ret = conf_source_reload (source);
+	TEST_EQ (ret, 0);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure no conf object created */
+	TEST_HASH_EMPTY (source->files);
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_EQ_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_EQ_P (job, NULL);
+
+	/* create conf */
+	f = fopen (filename, "w");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "start on started\n");
+	fprintf (f, "emits hello\n");
+	fprintf (f, "author \"foo\"\n");
+	fclose (f);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf loaded */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_NE_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_EQ_P (file->job, job);
+	TEST_EQ_STR ((job->emits)[0], "hello");
+
+	/* should pick up override, *NOT* conf */
+	TEST_EQ_P (job->start_on, NULL);
+	TEST_EQ_STR (job->author, "bar");
+
+	/* modify conf */
+	f = fopen (filename, "w");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "start on wibble\n");
+	fprintf (f, "emits moo\n");
+	fclose (f);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf reloaded and updated with override */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_NE_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_NE_P (job, NULL);
+	TEST_EQ_P (file->job, job);
+	TEST_EQ_STR ((job->emits)[0], "moo");
+
+	/* should pick up override, *NOT* conf */
+	TEST_EQ_P (job->start_on, NULL);
+	TEST_EQ_STR (job->author, "bar");
+
+	/* delete conf */
+	unlink (filename);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure conf object deleted */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_EQ_P (file, NULL);
+	TEST_HASH_EMPTY (source->files);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_EQ_P (job, NULL);
+	file = (ConfFile *)nih_hash_lookup (source->files, override);
+	TEST_EQ_P (file, NULL);
+
+	unlink (override);
+
+	/* ensure no conf object still */
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_EQ_P (file, NULL);
+	TEST_HASH_EMPTY (source->files);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_EQ_P (job, NULL);
+	file = (ConfFile *)nih_hash_lookup (source->files, override);
+	TEST_EQ_P (file, NULL);
+
+	nih_free (source);
+	TEST_EQ (rmdir (dirname), 0);
+
+
+	TEST_FEATURE ("create watch, override, then create/modify/delete conf");
+	TEST_ENSURE_CLEAN_ENV ();
+	TEST_FILENAME (dirname);
+	TEST_EQ (mkdir (dirname, 0755), 0);
+
+	/* create watch */
+	source = conf_source_new (NULL, dirname, CONF_JOB_DIR);
+	TEST_NE_P (source, NULL);
+	ret = conf_source_reload (source);
+	TEST_EQ (ret, 0);
+
+	strcpy (filename, dirname);
+	strcat (filename, "/foo.conf");
+	strcpy (override, dirname);
+	strcat (override, "/foo.override");
+
+	/* create override */
+	f = fopen (override, "w");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "manual\n");
+	fprintf (f, "author \"bar\"\n");
+	fclose (f);
+
+	TEST_FORCE_WATCH_UPDATE();
+
+	/* ensure no conf object created */
+	TEST_HASH_EMPTY (source->files);
+	file = (ConfFile *)nih_hash_lookup (source->files, filename);
+	TEST_EQ_P (file, NULL);
+	job = (JobClass *)nih_hash_lookup (job_classes, "foo");
+	TEST_EQ_P (job, NULL);
+
+	/* create conf */
+	f = fopen (filename, "w");
+	TEST_NE_P (f, NULL);
+	fprintf (f, "start on started\n");
+	fprintf (f, "emits hello\n");
+	fprintf (f, "author \"foo\"\n");
+	fclose (f);