Merge pull request #26 from glerchundi/master

implement how s6 behaves if stage2 fails

builder/build-latest

@@ -100,8 +100,11 @@ for output in "${outputs[@]}"; do
     mkdir -p $overlaydstpath/etc/s6/services/s6-fdholderd/supervise
     chmod 0700 $overlaydstpath/etc/s6/services/s6-fdholderd/supervise
 
-    # fix fix-attrs perms
+    # fix perms for utilities
     chmod 0755 $overlaydstpath/usr/bin/fix-attrs
+    chmod 0755 $overlaydstpath/usr/bin/import-from-envdir
+    chmod 0755 $overlaydstpath/usr/bin/with-contenv
+    chmod 0755 $overlaydstpath/usr/bin/with-notifywhenup
 
     # fix init perms
     chmod 0755 $overlaydstpath/init

builder/overlay-rootfs/etc/s6/init-catchall/init-stage2

@@ -5,20 +5,24 @@
 # environment.
 # Purpose of this file: to perform all the one-time initialization tasks.
 
-if -nt
+foreground
 {
   if
   {
     redirfd -w 1 /var/run/s6/uncaught-logs-fifo
     fdmove -c 2 1
 
-    /etc/s6/init/init-stage2-fix-attrs
-    /etc/s6/init/init-stage2-cont-inits
-    /etc/s6/init/init-stage2-services
+    /etc/s6/init/init-stage2-partial
   }
-
   /etc/s6/init/init-stage2-cmd $@
 }
-
-# if anything in the if -nt { } block fails, control jumps here.
+import -u ?
+if { s6-test ${?} -ne 0 }
+import-from-envdir -u -D 0 /var/run/s6/container_environment S6_BEHAVIOUR_IF_STAGE2_FAILS
+if { s6-test ${S6_BEHAVIOUR_IF_STAGE2_FAILS} -ne 0 }
+ifelse { s6-test ${S6_BEHAVIOUR_IF_STAGE2_FAILS} -ne 1 }
+{
+  # Stop supervision tree
+  s6-svscanctl -t /var/run/s6/services
+}
 s6-echo -- "\n!!!!!\n init-stage2 failed.\n Logs are in /var/log/s6-uncaught-logs\n!!!!!"

builder/overlay-rootfs/etc/s6/init-no-catchall/init-stage2

@@ -5,17 +5,18 @@
 # environment.
 # Purpose of this file: to perform all the one-time initialization tasks.
 
-if -nt
+foreground
 {
-  if
-  {
-    /etc/s6/init/init-stage2-fix-attrs
-    /etc/s6/init/init-stage2-cont-inits
-    /etc/s6/init/init-stage2-services
-  }
-
+  if { /etc/s6/init/init-stage2-partial }
   /etc/s6/init/init-stage2-cmd $@
 }
-
-# if anything in the if -nt { } block fails, control jumps here.
+import -u ?
+if { s6-test ${?} -ne 0 }
+import-from-envdir -u -D 0 /var/run/s6/container_environment S6_BEHAVIOUR_IF_STAGE2_FAILS
+if { s6-test ${S6_BEHAVIOUR_IF_STAGE2_FAILS} -ne 0 }
+ifelse { s6-test ${S6_BEHAVIOUR_IF_STAGE2_FAILS} -ne 1 }
+{
+  # Stop supervision tree
+  s6-svscanctl -t /var/run/s6/services
+}
 s6-echo -- "\n!!!!!\n init-stage2 failed.\n!!!!!"

builder/overlay-rootfs/etc/s6/init/init-stage1

@@ -18,17 +18,12 @@
 /usr/bin/s6-envdir /etc/s6/init/env
 /usr/bin/exec --
 
+
 ##
 ## route based on what was provided in S6_USE_CATCHALL_LOGGER
 ##
 
-backtick -n -D 0 S6_USE_CATCHALL_LOGGER
-{
-  if { s6-test -f /var/run/s6/container_environment/S6_USE_CATCHALL_LOGGER }
-  redirfd -r 0 /var/run/s6/container_environment/S6_USE_CATCHALL_LOGGER
-  s6-cat
-}
-import -u S6_USE_CATCHALL_LOGGER
+import-from-envdir -u -D 0 /var/run/s6/container_environment S6_USE_CATCHALL_LOGGER
 ifelse { s6-test ${S6_USE_CATCHALL_LOGGER} -eq 1 }
 {
   /etc/s6/init-catchall/init-stage1 $@

builder/overlay-rootfs/etc/s6/init/init-stage2-cmd

@@ -7,7 +7,10 @@
 
 if -t { s6-test $# -ne 0 }
 foreground { s6-setsid -gq -- with-contenv $@ }
-foreground { import -u ? s6-echo "${1} exited ${?}. Stopping the supervision tree." }
+import -u ?
+if { s6-echo "${1} exited ${?}" }
+
+# Stop supervision tree
 foreground { s6-svscanctl -t /var/run/s6/services }
 
 # Race condition here, but it's ok: the sync in stage 3 takes ages,

builder/overlay-rootfs/etc/s6/init/init-stage2-partial

@@ -0,0 +1,68 @@
+#!/usr/bin/execlineb -S0
+
+# this env decides what to do if stage2 fails
+import-from-envdir -u -D 0 /var/run/s6/container_environment S6_BEHAVIOUR_IF_STAGE2_FAILS
+
+foreground
+{
+	##
+	## fix-attrs.d: ensure owners and permissions are correct
+	##
+
+	if { s6-echo "[fix-attrs.d] applying owners & permissions fixes..." }
+	if
+	{
+	  pipeline { s6-ls -0 -- /etc/fix-attrs.d }
+	  pipeline { s6-sort -0 -- }
+	  forstdin -0 -- i
+	  import -u i
+	  if { s6-echo -n -- "[fix-attrs.d] applying ${i}... " }
+	  foreground { redirfd -r 0 /etc/fix-attrs.d/${i} fix-attrs }
+	  import -u ?
+	  if { s6-echo -- " exited ${?}" }
+	  ifelse { s6-test ${S6_BEHAVIOUR_IF_STAGE2_FAILS} -eq 0 } { exit 0 }
+	  exit ${?}
+	}
+	if { s6-echo -- "[fix-attrs.d] done." }
+
+
+	##
+	## cont-init.d: one-time init scripts
+	##
+
+	if { s6-echo "[cont-init.d] executing container initialization scripts..." }
+	if
+	{
+	  pipeline { s6-ls -0 -- /etc/cont-init.d }
+	  pipeline { s6-sort -0 -- }
+	  forstdin -o 0 -0 -- i
+	  import -u i
+	  if { s6-echo -n -- "[cont-init.d] executing ${i}... " }
+	  foreground { with-contenv /etc/cont-init.d/${i} }
+	  import -u ?
+	  if { s6-echo -- " exited ${?}" }
+	  ifelse { s6-test ${S6_BEHAVIOUR_IF_STAGE2_FAILS} -eq 0 } { exit 0 }
+	  exit ${?}
+	}
+	if { s6-echo -- "[cont-init.d] done." }
+
+	##
+	## services.d: long-lived processes to be supervised
+	##
+
+
+	if { s6-echo "[services.d] starting services" }
+	if
+	{
+	  pipeline { s6-ls -0 -- /etc/services.d }
+	  forstdin -0 -p -- i
+	  import -u i
+	  if { s6-test -d /etc/services.d/${i} }
+	  s6-hiercopy /etc/services.d/${i} /var/run/s6/services/${i}
+	}
+	if { s6-svscanctl -a /var/run/s6/services }
+	if { s6-echo -- "[services.d] done." }
+}
+import -u ?
+ifelse { s6-test ${S6_BEHAVIOUR_IF_STAGE2_FAILS} -eq 0 } { exit 0 }
+exit ${?}

builder/overlay-rootfs/etc/s6/init/init-stage3

@@ -15,12 +15,8 @@ foreground { s6-sync }
 
 foreground { s6-echo "[s6-finish] sending all processes the TERM signal." }
 foreground { s6-nuke -th } # foreground is process 1: it survives
-foreground
-{
-  with-contenv
-  /usr/bin/import -u -D 3000 S6_KILL_GRACETIME
-  /usr/bin/s6-sleep -m -- ${S6_KILL_GRACETIME}
-}
+import-from-envdir -u -D 3000 /var/run/s6/container_environment S6_KILL_GRACETIME
+foreground { s6-sleep -m -- ${S6_KILL_GRACETIME} }
 
 # Last message, then close our pipes and give the logger some time.
 foreground { s6-echo "[s6-finish] sending all processes the KILL signal and exiting." }

builder/overlay-rootfs/usr/bin/import-from-envdir

@@ -0,0 +1,29 @@
+#!/usr/bin/execlineb
+
+elgetopt "uD:"
+multisubstitute
+{
+  importas -u envdir 1
+  importas -u envvar 2
+  importas -u -D "" defval ELGETOPT_D
+  import -u -D 0 ELGETOPT_u
+}
+shift -n 2
+elgetpositionals -P0
+emptyenv -P
+backtick -n ${envvar}
+{
+  ifelse { s6-test -f ${envdir}/${envvar} }
+  {
+    redirfd -r 0 ${envdir}/${envvar}
+    s6-cat
+  }
+  s6-echo -n "${defval}"
+}
+ifelse { s6-test ${ELGETOPT_u} -eq 1 }
+{
+  import -u ${envvar}
+  $@
+}
+import ${envvar}
+$@