From 5d8640df60cf0ae4df73a003ac1787ab962ecb4c Mon Sep 17 00:00:00 2001
From: Didier Roche <didrocks@ubuntu.com>
Date: Tue, 3 Mar 2015 17:43:21 +0100
Subject: [PATCH] Add systemd-emergency-tmpfs to force tmpfs on /tmp

Force tmp.mount enablement if the system is low on disk space on /tmp.
Tag the mount as "overflow" so that various UIs can detect and warn the user
about this scenario. (LP: #1392637)
---
 debian/changelog                                |  4 ++++
 debian/extra/generators/systemd-emergency-tmpfs | 27 +++++++++++++++++++++++++
 debian/systemd.install                          |  1 +
 3 files changed, 32 insertions(+)
 create mode 100755 debian/extra/generators/systemd-emergency-tmpfs

diff --git a/debian/changelog b/debian/changelog
index faf9f5f..0ff0358 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -2,6 +2,10 @@ systemd (219-5) UNRELEASED; urgency=medium
 
   [ Didier Roche ]
   * Add "systemd-fsckd" autopkgtest. (LP: #1427312)
+  * Add systemd-emergency-tmpfs to force tmp.mount (tmpfs) enablement if the
+    system is low on disk space on /tmp. Tag the mount as "overflow" so that
+    various UIs can detect and warn the user about this scenario.
+    (LP: #1392637)
 
  -- Martin Pitt <mpitt@debian.org>  Tue, 03 Mar 2015 14:51:46 +0100
 
diff --git a/debian/extra/generators/systemd-emergency-tmpfs b/debian/extra/generators/systemd-emergency-tmpfs
new file mode 100755
index 0000000..180dbdf
--- /dev/null
+++ b/debian/extra/generators/systemd-emergency-tmpfs
@@ -0,0 +1,27 @@
+#!/bin/sh
+# mount /tmp as tmpfs if /tmp is full so that the system still tries to boot
+# tag it as "overflow" to warn the user.
+set -e
+
+NORMAL_DIR="$1"
+EARLY_DIR="$2"
+LATE_DIR="$3"
+
+UNIT_PATH=/lib/systemd/system/tmp.mount
+UNIT_OVERRIDE_PATH=${NORMAL_DIR}/tmp.mount.d
+LOCAL_FS_WANTS_PATH=${NORMAL_DIR}/local-fs.target.wants/
+
+avail=`df -BM -P /tmp/ | awk 'NR==2 { print substr($4, 0, length($4)-1) }'`
+min_size=50
+[ "$avail" -gt ${min_size} ] && return 0
+
+# add additional "overflow" tag
+mkdir -p ${UNIT_OVERRIDE_PATH}
+cat << EOF > ${UNIT_OVERRIDE_PATH}/99-emergency-tmpfs.conf
+[Mount]
+What=overflow
+EOF
+
+# enable it
+mkdir -p ${LOCAL_FS_WANTS_PATH}
+ln -s ${UNIT_PATH} ${LOCAL_FS_WANTS_PATH}
diff --git a/debian/systemd.install b/debian/systemd.install
index e0eaed5..e559195 100644
--- a/debian/systemd.install
+++ b/debian/systemd.install
@@ -53,3 +53,4 @@ usr/share/locale/
 ../../extra/tmpfiles.d/*.conf usr/lib/tmpfiles.d/
 ../../extra/debian-fixup lib/systemd/
 ../../extra/units/* lib/systemd/system/
+../../extra/generators/* lib/systemd/system-generators/
-- 
2.1.4