#!/bin/sh
#
# pg_upgrade: update a database without needing a full dump/reload cycle.
# CAUTION: read the manual page before trying to use this!

# $Header: /cvsroot/pgsql/src/bin/pg_dump/Attic/pg_upgrade,v 1.19 2002/01/09 16:08:54 momjian Exp $
#
# NOTE: we must be sure to update the version-checking code a few dozen lines
# below for each new PostgreSQL release.

TMPFILE="/tmp/pgupgrade.$$"

trap "rm -f $TMPFILE" 0 1 2 3 15

if [ "$#" -eq 0 ]
then	echo "Usage:  $0 -f inputfile old_data_dir" 1>&2
	exit 1
fi

if [ "X$1" = "X-f" ]
then	INPUT="$2"
	shift 2
	if [ ! -f "$INPUT" ]
	then	echo "$INPUT does not exist" 1>&2
		exit 1
	fi
else	echo "Usage:  $0 -f inputfile old_data_dir" 1>&2
	exit 1
fi

if [ "$#" -ne 1 ]
then	echo "Usage:  $0 -f inputfile old_data_dir" 1>&2
	exit 1
fi

OLDDIR="$1"

# check things

if [ ! -d "./data" ]
then	echo "`basename $0` must be run from the directory containing
the database directory \`data\' (`dirname $PGDATA`.)" 1>&2
	echo "You must have run initdb to create the template1 database." 1>&2
	exit 1
fi

if [ ! -d "./$OLDDIR" ]
then	echo "You must rename your old data directory to $OLDDIR and run initdb." 1>&2
	exit 1
fi

if [ ! -d "./data/base/1" ]
then	echo "Cannot find database template1 in ./data/base." 1>&2
	echo "Are you running $0 as the postgres superuser?" 1>&2
	exit 1
fi

if [ ! -d "./$OLDDIR/base/1" ]
then	echo "There is no database template1 in ./$OLDDIR/base." 1>&2
	exit 1
fi

if [ ! -r "./data/PG_VERSION" ]
then	echo "Cannot read ./data/PG_VERSION --- something is wrong." 1>&2
	exit 1
fi

if [ ! -r "./$OLDDIR/PG_VERSION" ]
then	echo "Cannot read ./$OLDDIR/PG_VERSION --- something is wrong." 1>&2
	exit 1
fi

# Get the actual versions seen in the data dirs.
DESTVERSION=`cat ./data/PG_VERSION`
SRCVERSION=`cat ./$OLDDIR/PG_VERSION`

# Check for version compatibility.
# This code will need to be updated/reviewed for each new PostgreSQL release.

# MYVERSION is the expected output database version
MYVERSION="7.1"

if [ "$DESTVERSION" != "$MYVERSION" -a "$DESTVERSION" != "$SRCVERSION" ]
then	echo "$0 is for PostgreSQL version $MYVERSION, but ./data/PG_VERSION contains $DESTVERSION." 1>&2
	echo "Did you run initdb for version $MYVERSION?" 1>&2
	exit 1
fi

# Check that input database is of a compatible version (anything with the same
# physical layout of user tables and indexes should be OK).  I did not write
# something like "$SRCVERSION -ge $MINVERSION" because test(1) isn't bright
# enough to compare dotted version strings properly.  Using a case statement
# looks uglier but is more flexible.

case "$SRCVERSION" in
#    7.2) ;;
    *)	echo "Sorry, `basename $0` cannot upgrade database version $SRCVERSION to $DESTVERSION." 1>&2
	echo "The on-disk structure of tables has changed." 1>&2
	echo "You will need to dump and restore using pg_dump." 1>&2
	exit 1;;
esac


# OK, ready to proceed.

# Execute the input script to create everything, except that we remove
# any COPY statements, except for the ones that load pg_shadow/pg_group.
# There shouldn't be any others in there anyway...

cat $INPUT | awk '	{
				if (tolower($1) == "copy" &&
				    $2 != "pg_shadow" &&
				    $2 != "pg_group")
					while (getline $0 > 0 && $0 != "\\.")
						;
				else	print $0;
			}' > $TMPFILE

psql "template1" < $TMPFILE

if [ $? -ne 0 ]
then	echo "There were errors in the input script $INPUT.
$0 aborted." 1>&2
	exit 1
fi

echo "Input script $INPUT complete, fixing row commit statuses..."

# Now vacuum each result database to mark all system-table rows as committed,
# because when pg_clog is replaced with the saved version, the transaction
# statuses will no longer match the data.  VACUUM will force the on-row
# status flags to the right value so that pg_clog will not matter anymore.
# Note: we used to try to do this as part of the previous step, but that
# risks permissions problems if VACUUM is run as the wrong user.
# Note: the initial VACUUM does template1, then we do everything else.

cat $INPUT | awk 'BEGIN	{ print "VACUUM;" }
			{
				if (tolower($1) == "copy")
					while (getline $0 > 0 && $0 != "\\.")
						;
				else if (tolower($1) == "\\connect" && 
					 $2 != "-" &&
					 $2 != "template1")
					printf "\\connect %s\nVACUUM;\n", $2;
			}' > $TMPFILE

psql "template1" < $TMPFILE

if [ $? -ne 0 ]
then	echo "There were errors in the vacuuming step.
$0 aborted." 1>&2
	exit 1
fi

# should be pretty small file
pg_dumpall -s > $TMPFILE 2>/dev/null

# flush buffers to disk
pg_ctl stop

echo "Commit fixes complete, moving data files..."

cat "$INPUT" | while read LINE
do
	if /bin/echo "$LINE" | grep -q "^\\\\connect "
	then	OLDDB="$DB"
		DB="`/bin/echo \"$LINE\" | cut -d' ' -f2`"
		if [ "$DB" = "-" ]
		then	DB="$OLDDB"
		fi
		if [ "$DB" = "template1" -o "$DB" = "template0" ]
		then	DB=""
		fi
	fi
	if echo "$LINE" | grep -q "^-- TOC Entry ID [0-9]* (OID "
	then	OID="`echo \"$LINE\" | cut -d' ' -f7 | tr -d ')'`"
	fi
	if echo "$LINE" | grep -q "^-- Name: [^ ]* Type: TABLE "
	then	TABLE="`echo \"$LINE\" | cut -d' ' -f3`"
		# skip system tables
		if [ "`echo \"$TABLE\" | cut -c 1-3`" = "pg_" ]
		then	TABLE=""
		fi
	fi
	if [ "$DB" -a "$OID" -a "$TABLE" ]
	then
		NEWOID=`awk -F' ' '
				BEGIN 	{ newdb=""; newoid=""; 
					  newtable=""; ret=0;}
				$1 == "\\\\connect" && $2 != "-" {newdb=$2;}
				$0 ~ /^-- TOC Entry ID [0-9]* .OID / \
					{ newoid = substr($7, 1, length($7)-1);}
				{print $0 >> "/tmp/x";
				print $3 >> "/tmp/x";
				print newdb," ", newoid >> "/tmp/x"}
				$0 ~ /^-- Name: [^ ]* Type: TABLE / && \
				newdb == "'"$DB"'" && \
				$3 == "'"$TABLE"'" \
					{ ret=newoid; exit}
				END { print ret;}' $TMPFILE`
		if [ "$NEWOID" -eq 0 ]
		then	echo "Move of database $DB, OID $OID, table $TABLE failed.\nNew oid not found;  exiting" 1>&2
			exit 1
		fi
		# We use stars so we don't have to worry about database oids
 		if [ `ls "$OLDDIR"/base/*/"$OID" | wc -l` -eq 0 ]
		then	echo "Move of database $DB, OID $OID, table $TABLE failed.\nFile not found;  exiting" 1>&2
			exit 1
		fi
  		if [ `ls "$OLDDIR"/base/*/"$OID" | wc -l` -gt 1 ]
		then	echo "Move of database $DB, OID $OID, table $TABLE failed.\nToo many found;  exiting" 1>&2
			exit 1
		fi
		if [ `ls data/base/*/"$NEWOID" | wc -l` -eq 0 ]
		then	echo "Move of database $DB, OID $OID, table $TABLE to $NEWOID failed.\nFile not found;  exiting" 1>&2
			exit 1
		fi
		if [ `ls data/base/*/"$NEWOID" | wc -l` -gt 1 ]
		then	echo "Move of database $DB, OID $OID, table $TABLE to $NEWOID failed.\nToo many found;  exiting" 1>&2
			exit 1
		fi
		mv -f "$OLDDIR"/base/*/"$OID" data/base/*/"$NEWOID"
		if [ "$?" -ne 0 ]
		then	echo "Move of database $DB, OID $OID, table $TABLE \n to $NEWOID failed.;  exiting" 1>&2
			exit 1
		fi
		TABLE=""
	fi
done

echo "You must stop/start the postmaster before doing anything else."
echo "You may remove the $OLDDIR directory with 'rm -r $OLDDIR'."

exit 0