service: avoid cryptic failure with old config

If user removes currently provided /etc/postgresql/postgresql
configuration file, PGDATA env variable is not set.  The
`systemctl start postgresql` would fail similarly to
`systemctl start postgresql@NOTCONFIGURED` when the configuration
file was not created yet with cryptic message
    "Usage: ... "

Stop this behavior rather explicitly with proper error in
check-db-dir script.

Warn also user in similar fashion that the configuration should be
adjusted in case the PGDATA was set directly in service file.

3 files changed, 31 insertions, 5 deletions

diff --git a/NEWS b/NEWS
index 9a17dac..52e7b82 100644
--- a/NEWS
+++ b/NEWS
@@ -1,5 +1,13 @@
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
+New in 0.9.2 version
+
+* The postgresql-check-db-dir is now more strict to admin's configuration
+  and tries to avoid future incompatibilities by warning about the
+  /etc/postgresql/$servicename file non-existence.
+
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
 New in 0.9.1 version
 
 * The postgresql-setup script does not require --port option when upgrading.
diff --git a/postgresql-check-db-dir.in b/postgresql-check-db-dir.in
index 3514247..2dd0649 100644
--- a/postgresql-check-db-dir.in
+++ b/postgresql-check-db-dir.in
@@ -7,14 +7,32 @@
 # bit slow to mount.  But we can at least emit a message advising newbies
 # what to do.
 
-PGDATA="$1"
+if test -z "$1"; then
+    echo "Maintainer error: $0 must be run with one argument"
+    exit 1
+fi
+
+service_name="$1"
+
+if [ -z "$PGDATA" ]; then
+    echo $"You try to start '$service_name' service"
+    echo $"but the required \$PGDATA environment variable is not set."
+    echo $"You should use the @PKGCONFIG_DIR@/$service_name"
+    echo $"configuration file to set \$PGDATA.  For more info see"
+    echo $"the @README_DIST@ file."
 
-if [ -z "$PGDATA" ]
-then
-    echo "Usage: $0 database-path"
     exit 1
 fi
 
+# Warn the user that the configuration should be adjusted.
+conf_file="@PKGCONFIG_DIR@/$service_name"
+if test ! -r "$conf_file"; then
+    echo >&2 $"WARNING: Note that file '$conf_file'"
+    echo >&2 $"does not exist.  Your configuration will be supported for some"
+    echo >&2 $"time but you are encouraged to create this file according to"
+    echo >&2 $"@README_DIST@ documentation."
+fi
+
 # Full PostgreSQL version, e.g. 9.0.2
 PGVERSION=@PGVERSION@
 
diff --git a/postgresql.service.in b/postgresql.service.in
index ad0a3e1..4b9fc95 100644
--- a/postgresql.service.in
+++ b/postgresql.service.in
@@ -27,7 +27,7 @@ OOMScoreAdjust=-1000
 Environment=PG_OOM_ADJUST_FILE=/proc/self/oom_score_adj
 Environment=PG_OOM_ADJUST_VALUE=0
 
-ExecStartPre=@libexecdir@/postgresql-check-db-dir ${PGDATA}
+ExecStartPre=@libexecdir@/postgresql-check-db-dir %N
 
 # Temporarily use postgresql-ctl wrapper around pg_ctl until there will
 # exist clients which set PGPORT in service file.