Merge lp:~jontai/openvista-gtm-integration/bug361512 into lp:openvista-gtm-integration

[Jon Tai]

[jeff.apple (jeff-apple)]

review: Approve

=== modified file 'scripts/usr/bin/ovbackup'
--- scripts/usr/bin/ovbackup	2009-04-14 23:29:49 +0000
+++ scripts/usr/bin/ovbackup	2009-04-15 17:31:43 +0000
@@ -47,8 +47,6 @@
     exit 2
 fi
 
-# FIXME: always clean up temp files, even on error
-
 # check permissions
 in_groups || {
     echo "ovbackup: permission denied" >&2
@@ -84,6 +82,17 @@
     exit 1
 }
 
+# the EXIT handler may or may not run if we're interrupted or killed depending
+# on the shell used (from what I've read, it does run on bash, but not on
+# dash); use $exit to exit with the correct status in both cases
+trap '[ -z "$exit" ] && rm -rf $tempdir; exit ${exit:-0}' EXIT
+
+trap 'logger -p user.info -t "ovbackup[$$]" -- Caught SIGINT, exiting; rm -rf $tempdir; exit ${exit:=130}' INT
+trap 'logger -p user.info -t "ovbackup[$$]" -- Caught SIGTERM, exiting; rm -rf $tempdir; exit ${exit:=143}' TERM
+
+# this signal is used to indicate failure of mupip backup, which is run in the background below
+trap 'logger -p user.info -t "ovbackup[$$]" -- Backup of $instance failed: Unable to copy database files; echo "ovbackup: Unable to copy database files" >&2; rm -rf $tempdir; exit ${exit:=1}' USR1
+
 {
     install -m 2750 -d "$tempdir/etc" &&
     cp -a "$root/$instance/etc/"*.conf "$tempdir/etc/"
@@ -118,36 +127,49 @@
 
 # use mupip backup to take a consistent snapshot of the globals
 #
-# note: - the snapshot is consistent to the moment this command is executed,
-# not to the moment the command finishes
+# run mupip backup in the background and immediately check to see if the
+# routines have changed.  if they have, we can abort the backup.  if they have
+# not, we wait for the backup to finish before moving on.  even if the routines
+# change after the backup has started, we will still have a consistent backup,
+# because the database backup is consistent to the moment when mupip backup
+# *starts*, not when mupip backup *finishes*.  if the backup fails, send
+# SIGUSR1 to the parent process (this script), which is handled above.
 (
     umask 007
     mupip backup DEFAULT "$tempdir/globals" 2>&1 \
       | grep -v '^$' \
       | logger -p user.info -t "ovbackup[$$]"
     retval=${PIPESTATUS[0]}
-    [ $retval -eq 0 ]   # hack to make subshell exit with exit code of mupip
-) || {
-    logger -p user.info -t "ovbackup[$$]" -- Backup of $instance failed: Unable to copy database files
-    echo "ovbackup: Unable to copy database files" >&2
-    exit 1
-}
-
-logger -p user.info -t "ovbackup[$$]" -- Checking backup integrity
-
-# FIXME: figure out a way to do this check while mupip backup is still running
-# - this shortens the window where routines must stay static and also makes the
-# backup process faster
+    [ $retval -eq 0 ] || kill -USR1 $$ 2> /dev/null
+) &
+child_pid=$!
+
+# wait for DEFAULT*.tmp or default.dat file to appear, indicating that the backup has begun (or is already finished)
+while [ 1 ]; do
+    if ls "$tempdir/globals" | grep -i default > /dev/null; then
+        break
+    fi
+    sleep 1
+done
+
+# meanwhile, check to see if the routines have changed
 #
 # FIXME: if the routines did change, we should probably try again instead of
 # just aborting - rsync the routines, then re-run the database backup
 output=`rsync -ai --delete --dry-run "$root/$instance/routines/" "$tempdir/routines/"`
 [ -z "$output" ] || {
     logger -p user.info -t "ovbackup[$$]" -- Backup of $instance failed: Routines changed during backup
-    echo "ovbackup: Routines changed during backup"
+    echo "ovbackup: Routines changed during backup" >&2
     exit 1
 }
 
+# if we get here, that means that the routines haven't changed, and either the
+# mupip backup is still running, or it completed successfully.  make sure it's
+# done before we move on.
+wait $child_pid 2> /dev/null
+
+logger -p user.info -t "ovbackup[$$]" -- Checking backup integrity
+
 mupip integ -file "$tempdir/globals/default.dat" 2>&1 \
   | grep -v '^$' \
   | logger -p user.info -t "ovbackup[$$]"
@@ -196,8 +218,6 @@
 
 logger -p user.info -t "ovbackup[$$]" -- Backup of $instance written to "$root/$instance/backups/${instance}-$timestamp.tar.bz2"
 
-rm -rf "$tempdir"
-
 # remove the oldest backup file until there are only $num_backups remaining
 until [ `find "$root/$instance/backups" -type f -name "*.tar.bz2" | wc -l` -le $num_backups ]; do
     delete=`find "$root/$instance/backups" -type f -name "*.tar.bz2" | sort | head -n 1`