Subject: [PATCH] Shepherd: Terminate all services upon SIGTERM or SIGHUP

From: Carlo Zancanaro <[email-masked]>
Date: Tue, 20 Feb 2018 04:11:45 +1100

Hey,

I use Shepherd to manage my user session, and if I log out then 
Shepherd leaves all my services running. This patch handles 
SIGTERM and SIGHUP to prevent that.

I hope the guix-patches mailing list was the right place to send 
it. From what I understand Shepherd development is done through 
the guix lists, so it seemed to make the most sense to me.

It's also worth noting that I had to run `gettextize` to get 
Shepherd to build on current master, but I haven't included those 
changes in this commit (because I don't know what should be 
committed and what shouldn't).

Carlo

From aabb9c6b1b52189d20339531de0b8b96bcace69f Mon Sep 17 00:00:00 2001
From: Carlo Zancanaro <[email-masked]>
Date: Tue, 20 Feb 2018 02:52:47 +1100
Subject: [PATCH] Terminate all services upon SIGTERM or SIGHUP

* modules/shepherd.scm (main): Add SIGTERM and SIGHUP handlers which stop
  root-service.
* tests/sigterm.sh, tests/sighup.sh: New files.
* Makefile.am (TESTS): Add tests/sigterm.sh and tests/sighup.sh.
---
 Makefile.am          |  5 ++++-
 modules/shepherd.scm | 11 ++++++++++
 tests/sighup.sh      | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 tests/sigterm.sh     | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 131 insertions(+), 1 deletion(-)
 create mode 100644 tests/sighup.sh
 create mode 100644 tests/sigterm.sh

diff --git a/Makefile.am b/Makefile.am
index a30b11d..021857d 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,6 +1,7 @@
 # Makefile.am -- How to build and install the Shepherd.
 # Copyright © 2002, 2003 Wolfgang Jährling <[email-masked]>
 # Copyright © 2013, 2014, 2015, 2016, 2018 Ludovic Courtès <[email-masked]>
+# Copyright © 2018 Carlo Zancanaro <[email-masked]>
 #
 # This file is part of the GNU Shepherd.
 #
@@ -188,7 +189,9 @@ TESTS =						\
   tests/no-home.sh				\
   tests/pid-file.sh				\
   tests/status-sexp.sh				\
-  tests/sigint.sh
+  tests/sigint.sh				\
+  tests/sigterm.sh				\
+  tests/sighup.sh
 
 TEST_EXTENSIONS = .sh
 EXTRA_DIST += $(TESTS)
diff --git a/modules/shepherd.scm b/modules/shepherd.scm
index 5334657..650ba63 100644
--- a/modules/shepherd.scm
+++ b/modules/shepherd.scm
@@ -1,6 +1,7 @@
 ;; shepherd.scm -- The daemon shepherd.
 ;; Copyright (C) 2013, 2014, 2016, 2018 Ludovic Courtès <[email-masked]>
 ;; Copyright (C) 2002, 2003 Wolfgang Jährling <[email-masked]>
+;; Copyright (C) 2018 Carlo Zancanaro <[email-masked]>
 ;;
 ;; This file is part of the GNU Shepherd.
 ;;
@@ -182,6 +183,16 @@
       (lambda _
         (stop root-service)))
 
+    ;; Stop everything when we get SIGTERM.
+    (sigaction SIGTERM
+      (lambda _
+        (stop root-service)))
+
+    ;; Stop everything when we get SIGHUP.
+    (sigaction SIGHUP
+      (lambda _
+        (stop root-service)))
+
     ;; Ignore SIGPIPE so that we don't die if a client closes the connection
     ;; prematurely.
     (sigaction SIGPIPE SIG_IGN)
diff --git a/tests/sighup.sh b/tests/sighup.sh
new file mode 100644
index 0000000..e9ca84b
--- /dev/null
+++ b/tests/sighup.sh
@@ -0,0 +1,58 @@
+# GNU Shepherd --- Make sure SIGHUP is correctly handled.
+# Copyright © 2014, 2016 Ludovic Courtès <[email-masked]>
+# Copyright © 2018 Carlo Zancanaro <[email-masked]>
+#
+# This file is part of the GNU Shepherd.
+#
+# The GNU Shepherd is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or (at
+# your option) any later version.
+#
+# The GNU Shepherd 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 the GNU Shepherd.  If not, see <http://www.gnu.org/licenses/>.
+
+shepherd --version
+herd --version
+
+socket="t-socket-$$"
+conf="t-conf-$$"
+log="t-log-$$"
+stamp="t-stamp-$$"
+pid="t-pid-$$"
+
+herd="herd -s $socket"
+
+trap "rm -f $socket $conf $stamp $log;
+      test -f $pid && kill \`cat $pid\` || true; rm -f $pid" EXIT
+
+cat > "$conf"<<EOF
+(use-modules (srfi srfi-26))
+(register-services
+ (make <service>
+   #:provides '(test)
+   #:start (const #t)
+   #:stop  (lambda _
+             (call-with-output-file "$stamp"
+               (lambda (port)
+                 (display "stopped" port))))
+   #:respawn? #f))
+ (start 'test)
+EOF
+
+rm -f "$pid" "$stamp"
+shepherd -I -s "$socket" -c "$conf" --pid="$pid" --log="$log" &
+
+while [ ! -f "$pid" ] ; do sleep 0.5 ; done
+
+# Send SIGTERM to shepherd.
+kill -HUP "`cat "$pid"`"
+while kill -0 "`cat "$pid"`" ; do sleep 0.5 ; done
+
+# Make sure the service's 'stop' method was called.
+test -f "$stamp"
diff --git a/tests/sigterm.sh b/tests/sigterm.sh
new file mode 100644
index 0000000..f6b66be
--- /dev/null
+++ b/tests/sigterm.sh
@@ -0,0 +1,58 @@
+# GNU Shepherd --- Make sure SIGTERM is correctly handled.
+# Copyright © 2014, 2016 Ludovic Courtès <[email-masked]>
+# Copyright © 2018 Carlo Zancanaro <[email-masked]>
+#
+# This file is part of the GNU Shepherd.
+#
+# The GNU Shepherd is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or (at
+# your option) any later version.
+#
+# The GNU Shepherd is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with the GNU Shepherd.  If not, see <http://www.gnu.org/licenses/>.
+
+shepherd --version
+herd --version
+
+socket="t-socket-$$"
+conf="t-conf-$$"
+log="t-log-$$"
+stamp="t-stamp-$$"
+pid="t-pid-$$"
+
+herd="herd -s $socket"
+
+trap "rm -f $socket $conf $stamp $log;
+      test -f $pid && kill \`cat $pid\` || true; rm -f $pid" EXIT
+
+cat > "$conf"<<EOF
+(use-modules (srfi srfi-26))
+(register-services
+ (make <service>
+   #:provides '(test)
+   #:start (const #t)
+   #:stop  (lambda _
+             (call-with-output-file "$stamp"
+               (lambda (port)
+                 (display "stopped" port))))
+   #:respawn? #f))
+ (start 'test)
+EOF
+
+rm -f "$pid" "$stamp"
+shepherd -I -s "$socket" -c "$conf" --pid="$pid" --log="$log" &
+
+while [ ! -f "$pid" ] ; do sleep 0.5 ; done
+
+# Send SIGTERM to shepherd.
+kill -TERM "`cat "$pid"`"
+while kill -0 "`cat "$pid"`" ; do sleep 0.5 ; done
+
+# Make sure the service's 'stop' method was called.
+test -f "$stamp"
-- 
2.16.1