###
### common shell include for dbconfig-common aware packages.
###
# usage: /usr/share/dbconfig-common/dpkg/common $package $dpkg_argv
# (where $dpkg_argv is $@ as passed to the maintainer scripts)

#set -x

# get some internal helper functions, like _dbc_sanity_check
. /usr/share/dbconfig-common/internal/common

dbc_config(){
	_dbc_debug "dbc_config() $@"
	###
	### some global variables
	###
	dbc_share="/usr/share/dbconfig-common"
	dbc_package="$1"
	dbc_basepackage=`echo $dbc_package | cut -d_ -f1`
	dbc_command="$2"
	dbc_oldversion="$3"

	if ! _dbc_sanity_check package command; then
		dbc_install_error "determining package or command";
	fi

	dbc_confdir="/etc/dbconfig-common"
	dbc_globalconfig="$dbc_confdir/config"
	dbc_packageconfig="$dbc_confdir/$dbc_package.conf"

	###
	### some internal variables
	###
	# templates common to all database types
	dbc_standard_templates="database-type dbconfig-install dbconfig-upgrade dbconfig-remove dbconfig-reinstall password-confirm app-password-confirm purge upgrade-backup passwords-do-not-match install-error upgrade-error remove-error internal/reconfiguring internal/skip-preseed missing-db-package-error"

	# templates common to mysql database types
	dbc_mysql_templates="mysql/method remote/host remote/newhost mysql/app-pass mysql/admin-user mysql/admin-pass remote/port db/dbname db/app-user"

	# templates common to postgresql database types
	dbc_pgsql_templates="pgsql/method remote/host remote/newhost pgsql/app-pass pgsql/admin-user pgsql/admin-pass remote/port pgsql/authmethod-admin pgsql/authmethod-user pgsql/changeconf pgsql/manualconf db/dbname db/app-user pgsql/no-empty-passwords"

	# templates common to sqlite database types
	dbc_sqlite_templates="db/dbname db/basepath"

	# all dbtypes supported by dbconfig-common
	dbc_all_supported_dbtypes="mysql pgsql sqlite sqlite3"

	# database types supporting authenticated access
	dbc_authenticated_dbtypes="mysql pgsql"

	# database types supporting remote access
	dbc_remote_dbtypes="mysql pgsql"

	# database types storing files on the filesystem
	dbc_fs_dbtypes="sqlite sqlite3"

	###
	### source the pre-existing config, if it exists
	###
	if [ -f $dbc_globalconfig ]; then
		. $dbc_globalconfig
	fi
	# set the priority of "remote database" related questions for
	# the database types that support it
	if [ "$dbc_remote_questions_default" = "true" ]; then
		dbc_remote_questions_priority="high"
		dbc_default_pgsql_authmethod_admin="password"
	else
		dbc_remote_questions_priority="low"
		dbc_default_pgsql_authmethod_admin="ident"
	fi

	dbc_set_dbtype_defaults $dbc_dbtype
}

dbc_set_dbtype_defaults(){
	_dbc_debug "dbc_set_dbtype_defaults() $@"

	# if dbtype isn't set, but dbc_hardcoded_dbtype is set, set dbtype to that
	if [ "$dbc_hardcoded_dbtype" ]; then
		dbc_dbtype="$dbc_hardcoded_dbtype"
	fi

	###
	### dbtype-specific variable section
	###
	dbc_default_basepath=""

	# now set some variables based on the dbtype
	dbc_db_installed_cmd="dbc_${dbc_dbtype}_db_installed"
	case $dbc_dbtype in
	mysql)
		. /usr/share/dbconfig-common/internal/mysql
		dbc_createuser_cmd='dbc_mysql_createuser'
		dbc_checkuser_cmd='dbc_mysql_check_user'
		dbc_createdb_cmd='dbc_mysql_createdb'
		dbc_dropdb_cmd='dbc_mysql_dropdb'
		dbc_dropuser_cmd='dbc_mysql_dropuser'
		dbc_sqlexec_cmd='dbc_mysql_exec_command'
		dbc_sqlfile_cmd='dbc_mysql_exec_file'
		dbc_dump_cmd='dbc_mysql_dump'
		dbc_register_templates="$dbc_standard_templates $dbc_mysql_templates"
		dbc_default_admin="root"
		dbc_default_dbuser=`echo $dbc_package | tr -d +. | cut -c -16`;
		dbc_dbvendor="MySQL"
		dbc_dbpackage="mysql-server"
		dbc_dbclientpackage="mysql-client"
	;;
	pgsql)
		. /usr/share/dbconfig-common/internal/pgsql
		dbc_createuser_cmd='dbc_pgsql_createuser'
		dbc_checkuser_cmd='dbc_pgsql_check_user'
		dbc_createdb_cmd='dbc_pgsql_createdb'
		dbc_dropdb_cmd='dbc_pgsql_dropdb'
		dbc_dropuser_cmd='dbc_pgsql_dropuser'
		dbc_sqlexec_cmd='dbc_pgsql_exec_command'
		dbc_sqlfile_cmd='dbc_pgsql_exec_file'
		dbc_dump_cmd='dbc_pgsql_dump'
		dbc_register_templates="$dbc_standard_templates $dbc_pgsql_templates"
		dbc_default_admin="postgres"
		dbc_default_dbuser=`echo $dbc_package | tr -d +-.`;
		dbc_use_dbuser="false"
		dbc_dbvendor="PostgreSQL"
		dbc_dbpackage="postgresql"
		dbc_dbclientpackage="postgresql-client"
	;;
	sqlite|sqlite3)
		. /usr/share/dbconfig-common/internal/sqlite
		dbc_createuser_cmd=true
		dbc_checkuser_cmd=true
		dbc_createdb_cmd='dbc_sqlite_createdb'
		dbc_dropdb_cmd='dbc_sqlite_dropdb'
		dbc_dropuser_cmd=true
		dbc_sqlexec_cmd='dbc_sqlite_exec_command'
		dbc_sqlfile_cmd='dbc_sqlite_exec_file'
		dbc_dump_cmd='dbc_sqlite_dump'
		dbc_register_templates="$dbc_standard_templates $dbc_sqlite_templates"
		dbc_default_admin=""
		dbc_default_dbuser="";
		dbc_default_basepath="/var/lib/dbconfig-common/$dbc_dbtype/$dbc_package"
		dbc_use_dbuser="false"
		dbc_dbvendor="SQLite"
		dbc_sqlite_cmd="/usr/bin/$dbc_dbtype"
		dbc_dbpackage="$dbc_dbtype"
		dbc_dbclientpackage="$dbc_dbtype"
	;;
	*)
		dbc_register_templates="$dbc_standard_templates $dbc_mysql_templates $dbc_pgsql_templates $dbc_sqlite_templates"
	;;
	esac

	# but if this is a frontend-only app, reset some of the above to noops
	if [ "$dbc_frontend" ]; then
		dbc_createuser_cmd=true
		dbc_checkuser_cmd=true
		dbc_createdb_cmd=true
		dbc_dropdb_cmd=true
		dbc_dropuser_cmd=true
		dbc_sqlexec_cmd=true
		dbc_sqlfile_cmd=true
		dbc_dump_cmd=true
	fi
}


###
### functions
###

###
### dump global configuration to a config file
###
dbc_write_global_config(){
	local tfile
	_dbc_debug "dbc_write_global_config() $@"

	tfile=`dbc_mktemp`
	cat << EOF > "$tfile"
# dbconfig-common system-wide configuration options

# dbc_remember_admin_pass: should we cache administrative passwords?
#	set to "true" to keep admin passwords cached in debconf
dbc_remember_admin_pass='$dbc_remember_admin_pass'

# dbc_remote_questions_default: will we be likely to install on remote servers?
#	set to "true" to raise the priority of debconf questions related to
#   database installation on remote servers (for database types that support this)
dbc_remote_questions_default='$dbc_remote_questions_default'

EOF
	ucf --debconf-ok "$tfile" "$dbc_globalconfig"
	ucfr dbconfig-common "$dbc_globalconfig"
	rm -f "$tfile"
}

dbc_read_package_config(){
	_dbc_debug "dbc_read_package_config() $@"
	_dbc_sanity_check package packageconfig || dbc_install_error
	
	# first we set some defaults, which will be overridden by the config
	dbc_install=true
	dbc_upgrade=true

	if [ -f $dbc_packageconfig ]; then
		. $dbc_packageconfig
	fi

	# if dbserver is unset, that means localhost.
	if [ -z "$dbc_dbserver" ] || [ "$dbc_dbserver" = "localhost" ]; then
		# if the server is local, only allow connections from localhost
		dbc_dballow="localhost"
	else
		# otherwise, only tell the remote database to allow from us
		dbc_dballow=`hostname -f`
	fi
}

###
### this function is responsible for setting all debconf values based
### on the contents of on-system config files, so that we can avoid
### the "Debconf is Not a Registry" dilemma.
###
dbc_preseed_package_debconf(){
	local skip_preseed
	_dbc_debug "dbc_preseed_package_debconf() $@"
	_dbc_sanity_check package || dbc_install_error

	# if we've pre-configured the package and are running config
	# for the second time via dpkg, then there is no on-disk
	# configuration to preseed with, and we would in fact nuke
	# the previous answers.  so we check to avoid that.
	db_get $dbc_package/internal/skip-preseed && skip_preseed="$RET"
	db_reset $dbc_package/internal/skip-preseed
	if [ "$skip_preseed" = "true" ]; then 
		dbc_read_package_debconf
		return 0 
	fi

	# set whether they want our help
	db_set $dbc_package/dbconfig-install "$dbc_install"
	db_set $dbc_package/dbconfig-upgrade "$dbc_upgrade"
	db_set $dbc_package/dbconfig-remove "$dbc_remove"

	# set the dbtype
	db_set $dbc_package/database-type "$dbc_dbtype"

	# the following db-specific settings always need to be preseeded unless
	# we specifically know we're not configuring for the given database type
	#
	# set the psql authentication method
	if [ -z "$dbc_dbtype" ] || [ "$dbc_dbtype" = "pgsql" ]; then
		if [ "$dbc_authmethod_admin" ]; then
			db_set $dbc_package/pgsql/authmethod-admin "$dbc_authmethod_admin"
		elif [ "$dbc_default_pgsql_authmethod_admin" ]; then
			db_set $dbc_package/pgsql/authmethod-admin "$dbc_default_pgsql_authmethod_admin"
		fi
		if [ "$dbc_authmethod_user" ]; then
			db_set $dbc_package/pgsql/authmethod-user "$dbc_authmethod_user"
		fi
	fi

	# for authenticated-only dbtypes.  also catches empty (multidb) type.
	if echo "$dbc_authenticated_dbtypes" | grep -q "$dbc_dbtype"; then
		# set app user
		if [ "$dbc_dbuser" ]; then
			db_set $dbc_package/db/app-user "$dbc_dbuser"
		fi

		# set the app user password
		if [ "$dbc_dbpass" ]; then
			db_set $dbc_package/$dbc_dbtype/app-pass "$dbc_dbpass"
		fi

		# set the database administrator name
		if [ "$dbc_dbadmin" ]; then
			db_set $dbc_package/$dbc_dbtype/admin-user "$dbc_dbadmin"
		fi
	fi

	# for remote-capable dbtypes
	if echo "$dbc_remote_dbtypes" | grep -q "$dbc_dbtype"; then
		# set the remote server/port
		if [ "$dbc_dbserver" ]; then
			db_set $dbc_package/remote/host "$dbc_dbserver"
		fi
		if [ "$dbc_dbport" ]; then
			db_set $dbc_package/remote/port "$dbc_dbport"
		fi
	fi

	# for fs-based dbtypes only (sqlite)
	if echo "$dbc_fs_dbtypes" | grep -qa "$dbc_dbtype"; then
		# set the directory that the database file is found in
		if [ "$dbc_basepath" ]; then
			db_set $dbc_package/db/basepath "$dbc_basepath"
		fi
	fi

	# set the name of the database to be created
	if [ "$dbc_dbname" ]; then
		db_set $dbc_package/db/dbname "$dbc_dbname"
	fi

	case $dbc_dbtype in
	"pgsql")
		# ident based auth doesn't need a password
		if [ "$dbc_authmethod_admin" != "ident" ]; then
			# set the database administrator pass
			db_set $dbc_package/pgsql/admin-pass "$dbc_dbadmpass"
		fi
		if [ "$dbc_authmethod_user" != "ident" ]; then
			# set the database user pass
			db_set $dbc_package/pgsql/app-pass "$dbc_dbpass"
		fi

		# set whether or not they want to force SSL
		if [ "$dbc_ssl" = "true" ]; then
			db_set $dbc_package/pgsql/method "tcp/ip + ssl"
		fi
	;;
	esac
}


###
### this function is responsible for reading in everything 
### with respect to the package's configuration and dbconfig-common.  
###
dbc_read_package_debconf(){
	_dbc_debug "dbc_read_package_debconf() $@"
	_dbc_sanity_check package || dbc_install_error

	# gracefully fetch this to support multi-dbtype packages
	if [ ! "$dbc_hardcoded_dbtype" ]; then
		db_get $dbc_package/database-type && dbc_dbtype="$RET"
	fi
	# dbconfig needs to be reloaded at this point for multi-dbtype apps
	dbc_set_dbtype_defaults $dbc_dbtype

	# get whether they want our help with various stuff
	db_get $dbc_package/dbconfig-install && dbc_install="$RET"
	db_get $dbc_package/dbconfig-upgrade && dbc_upgrade="$RET"
	db_get $dbc_package/dbconfig-remove && dbc_remove="$RET"

	# if they don't want help, then we're done and return early
	if [ "$dbc_install" != "true" ]; then return 0; fi
	
	# otherwise, just to make sure dbtype is set...
	_dbc_sanity_check dbtype || dbc_install_error

	if echo "$dbc_authenticated_dbtypes" | grep -q "$dbc_dbtype"; then
		# get app user
		db_get $dbc_package/db/app-user && dbc_dbuser="$RET"

		# get the app user password
		db_get $dbc_package/$dbc_dbtype/app-pass && dbc_dbpass="$RET"

		# get the database administrator name
		db_get $dbc_package/$dbc_dbtype/admin-user && dbc_dbadmin="$RET"

		# get the database administrator pass
		db_get $dbc_package/$dbc_dbtype/admin-pass && dbc_dbadmpass="$RET"
	fi

	if echo "$dbc_remote_dbtypes" | grep -q "$dbc_dbtype"; then

		# get the db server/port
		db_get $dbc_package/remote/host && dbc_dbserver="$RET"
		db_get $dbc_package/remote/port && dbc_dbport="$RET"
	fi

	if echo "$dbc_fs_dbtypes" | grep -qa "$dbc_dbtype"; then
		# get the directory that the database file is found in
		db_get $dbc_package/db/basepath && dbc_basepath="$RET"
	fi

	# get the name of the database to be created
	db_get $dbc_package/db/dbname && dbc_dbname="$RET"

	# a few db-specific things
	case $dbc_dbtype in
	"pgsql")
		# get the psql authentication method
		db_get $dbc_package/pgsql/authmethod-admin && dbc_authmethod_admin="$RET"
		db_get $dbc_package/pgsql/authmethod-user && dbc_authmethod_user="$RET"

		# get whether or not they want to force SSL
		db_get $dbc_package/pgsql/method && dbc_method="$RET"
		if [ "$dbc_method" = "tcp/ip + ssl" ]; then
			dbc_ssl="true"
		fi
	;;
	esac

	if [ "$dbc_debug" ]; then
		_dbc_debug "settings determined from dbc_read_package_debconf:"
		_dbc_debug "\tdbc_install=$dbc_install"
		_dbc_debug "\tdbc_upgrade=$dbc_upgrade"
		_dbc_debug "\tdbc_remove=$dbc_remove"
		_dbc_debug "\tdbc_dbtype=$dbc_dbtype"
		_dbc_debug "\tdbc_dbuser=$dbc_dbuser"
		_dbc_debug "\tdbc_dbpass=$dbc_dbpass"
		_dbc_debug "\tdbc_dbadmin=$dbc_dbadmin"
		_dbc_debug "\tdbc_dbadmpass=$dbc_dbadmpass"
		_dbc_debug "\tdbc_dbserver=$dbc_dbserver"
		_dbc_debug "\tdbc_dbport=$dbc_dbport"
		_dbc_debug "\tdbc_dbname=$dbc_dbname"
		_dbc_debug "\tdbc_authmethod_admin=$dbc_authmethod_admin"
		_dbc_debug "\tdbc_authmethod_user=$dbc_authmethod_user"
		_dbc_debug "\tdbc_ssl=$dbc_ssl"
	fi
}

###
### dump package configuration to a config file
###
dbc_write_package_config(){
	local iformat ofile tfile
	_dbc_debug "dbc_write_package_config() $@"
	_dbc_sanity_check packageconfig || dbc_install_error
	echo "dbconfig-common: writing config to $dbc_packageconfig" >&2

	tfile=`dbc_mktemp dbconfig-package-config.XXXXXX`

	# a quick check if this is a multi-dbtype app
	if [ "$dbc_hardcoded_dbtype" ]; then
		dbc_dbtype="$dbc_hardcoded_dbtype"
	fi
	# and a check for ssl
	if [ "$dbc_method" = "tcp/ip + ssl" ]; then
		dbc_ssl="true"
	fi

	cat << EOF > $tfile
# automatically generated by the maintainer scripts of $dbc_package
# any changes you make will be preserved, though your comments
# will be lost!  to change your settings you should edit this
# file and then run "dpkg-reconfigure $dbc_package"

# dbc_install: configure database with dbconfig-common?
#              set to anything but "true" to opt out of assistance
dbc_install='`dbc_sq_escape $dbc_install`'

# dbc_upgrade: upgrade database with dbconfig-common?
#              set to anything but "true" to opt out of assistance
dbc_upgrade='`dbc_sq_escape $dbc_upgrade`'

# dbc_remove: deconfigure database with dbconfig-common?
#             set to anything but "true" to opt out of assistance
dbc_remove='`dbc_sq_escape $dbc_remove`'

# dbc_dbtype: type of underlying database to use
#	this exists primarily to let dbconfig-common know what database
#	type to use when a package supports multiple database types.  
#	don't change this value unless you know for certain that this
#	package supports multiple database types
dbc_dbtype='`dbc_sq_escape $dbc_dbtype`'

# dbc_dbuser: database user
#	the name of the user who we will use to connect to the database.
dbc_dbuser='`dbc_sq_escape $dbc_dbuser`'

# dbc_dbpass: database user password
#	the password to use with the above username when connecting
#	to a database, if one is required
dbc_dbpass='`dbc_sq_escape $dbc_dbpass`'

# dbc_dbserver: database host.  
#	leave unset to use localhost (or a more efficient local method
#	if it exists).
dbc_dbserver='`dbc_sq_escape $dbc_dbserver`'

# dbc_dbport: remote database port
#	leave unset to use the default.  only applicable if you are
#	using a remote database.
dbc_dbport='`dbc_sq_escape $dbc_dbport`'

# dbc_dbname: name of database
#	this is the name of your application's database.
dbc_dbname='`dbc_sq_escape $dbc_dbname`'

# dbc_dbadmin: name of the administrative user
#	this is the administrative user that is used to create all of the above
dbc_dbadmin='`dbc_sq_escape $dbc_dbadmin`'

# dbc_basepath: base directory to hold database files
#	leave unset to use the default.  only applicable if you are
#	using a local (filesystem based) database.    
dbc_basepath='`dbc_sq_escape $dbc_basepath`'

##
## postgresql specific settings.  if you don't use postgresql,
## you can safely ignore all of these
##

# dbc_ssl: should we require ssl?
#	set to "true" to require that connections use ssl
dbc_ssl='`dbc_sq_escape $dbc_ssl`'

# dbc_authmethod_admin: authentication method for admin
# dbc_authmethod_user: authentication method for dbuser
#	see the section titled "AUTHENTICATION METHODS" in
#	/usr/share/doc/dbconfig-common/README.pgsql for more info
dbc_authmethod_admin='`dbc_sq_escape $dbc_authmethod_admin`'
dbc_authmethod_user='`dbc_sq_escape $dbc_authmethod_user`'

##
## end postgresql specific settings
##

EOF
	# apps registered via webapps-common might use nested directories, so
	# we should make sure the directories exist
	mkdir -p "`dirname \"$dbc_packageconfig\"`"
	ucf --debconf-ok "$tfile" "$dbc_packageconfig"
	ucfr "$dbc_package" "$dbc_packageconfig"
	rm -f "$tfile"
  # generate the requested d-g-i config files unless it's a manual install
  # and we've been explicitly told to avoid doing this
  if [ "$dbc_install" != "true" ] && [ "$dbc_dgi_on_manual" != "true" ]; then
    return 0
  elif [ "$dbc_generate_include" ]; then
      if echo $dbc_generate_include | grep -q -E "^[^:]*:"; then
	  iformat=`echo $dbc_generate_include | cut -d: -f1`
	  ofile=`echo $dbc_generate_include | cut -d: -f2`

          # Changing the owner and perms should only be done during installation,
          # as administrator changes to configuration files must be respected.
          # Therefor, only processing owner and perms items when the target
          # file does not exist. This also works correctly when the configuration
          # file is removed alltogether, as ucf won't create the file.
	  # This change can be done with all the Oct 2014 usage of dbconfig-common
	  # (Checked with http://codesearch.debian.net), as long as no package
	  # starts asking for the ownership or permissions and expects it to be
	  # changed.
          # See BTS: #720517
	  if [ ! -e "$ofile" ]; then
	      if [ "$dbc_generate_include_owner" ]; then
		  dbc_generate_include_args="$dbc_generate_include_args -O $dbc_generate_include_owner"
	      fi
	      if [ "$dbc_generate_include_perms" ]; then
		  dbc_generate_include_args="$dbc_generate_include_args -m $dbc_generate_include_perms"
	      fi
	  fi

	  dbconfig-generate-include -a -f "$iformat" $dbc_generate_include_args -U "$dbc_packageconfig" "$ofile"
	  ucfr "$dbc_package" "$dbc_packageconfig"
      else
	  dbc_error="maintainer did not properly set dbc_generate_include"
	  dbc_install_error "writing package config"
      fi
  fi
}


dbc_abort(){
	# forget that we've seen all the debconf questions
	for f in $dbc_register_templates; do
		db_fset $dbc_package/$f seen false
	done

	echo "dbconfig-common: $dbc_package $dbc_command: aborted." >&2
	dbc_postinst_cleanup
	return 1
}


##
## what to do if mysql-server etc are not installed
##
dbc_missing_db_package_error(){
	local question
	echo "warning: database package not installed?" >&2
	question="$dbc_package/missing-db-package-error"
	db_fset $question seen false
	db_subst $question dbpackage $1
	db_input critical $question || true
	db_go || true
	db_get $question
	_dbc_on_error_option="$RET"

	if [ "${DEBIAN_FRONTEND:-}" = "noninteractive" ]; then
		_dbc_on_error_option="ignore"
	fi
	
	if [ "$_dbc_on_error_option" = "abort" ]; then
		dbc_abort
	fi
	
	if [ "$_dbc_on_error_option" = "retry" ]; then
		# forget that we've seen all the debconf questions
		for f in $dbc_register_templates; do
			db_fset $dbc_package/$f seen false
		done
		
		echo "dbconfig-common: $dbc_package $dbc_command: trying again." >&2
                . /usr/share/dbconfig-common/dpkg/config
                dbc_go $dbc_package configure $dbc_oldversion
                . /usr/share/dbconfig-common/dpkg/postinst
		dbc_go $dbc_package $dbc_command $dbc_oldversion 
		dbc_tried_again="yes"
	fi
}

##
## what to do when something goes wrong during install
##
dbc_install_error(){
	echo "error encountered $1:" >&2
	echo $dbc_error >&2
	if [ "$_dbc_no_act" ]; then
		return 0;
	fi
	db_fset $dbc_package/install-error seen false
	db_subst $dbc_package/install-error error $dbc_error
	db_input critical $dbc_package/install-error || true
	db_go || true
	db_get $dbc_package/install-error
	_dbc_on_error_option="$RET"

	if [ "${DEBIAN_FRONTEND:-}" = "noninteractive" ]; then
		echo "dbconfig-common: $dbc_package $dbc_command: noninteractive fail." >&2
		_dbc_on_error_option="ignore"
	fi
	
	if [ "$_dbc_on_error_option" = "abort" ]; then
		dbc_abort
	fi
	
	if [ "$_dbc_on_error_option" = "retry" ]; then
		# forget that we've seen all the debconf questions
		for f in $dbc_register_templates; do
			db_fset $dbc_package/$f seen false
		done
		
		echo "dbconfig-common: $dbc_package $dbc_command: trying again." >&2
                . /usr/share/dbconfig-common/dpkg/config
                dbc_go $dbc_package configure $dbc_oldversion
                . /usr/share/dbconfig-common/dpkg/postinst
		dbc_go $dbc_package $dbc_command $dbc_oldversion 
		dbc_tried_again="yes"
	fi
	
	if [ "$_dbc_on_error_option" = "retry (skip questions)" ]; then
		echo "dbconfig-common: $dbc_package $dbc_command: trying again (skip questions)." >&2
                . /usr/share/dbconfig-common/dpkg/postinst
		dbc_go $dbc_package $dbc_command $dbc_oldversion 
		dbc_tried_again="yes"
	fi

	if [ "$_dbc_on_error_option" = "ignore" ]; then
		echo "dbconfig-common: $dbc_package $dbc_command: ignoring errors from here forwards" 2>&1
		# XXX this would be better
		_dbc_no_act="true"
		dbc_checkuser_cmd=true
		dbc_createdb_cmd=true
		dbc_createuser_cmd=true
		dbc_dbvendor=true
		dbc_default_admin=true
		dbc_default_dbuser=true
		dbc_dropdb_cmd=true
		dbc_dropuser_cmd=true
		dbc_dump_cmd=true
		dbc_register_templates=true
		dbc_sqlexec_cmd=true
		dbc_sqlfile_cmd=true
		dbc_use_dbuser=true
		return 0
	fi
}

##
## what to do when something goes wrong during upgrade
##
dbc_upgrade_error(){
	echo "error encountered $1:" >&2
	echo $dbc_error >&2
	db_fset $dbc_package/upgrade-error seen false
	db_subst $dbc_package/upgrade-error error $dbc_error
	db_subst $dbc_package/upgrade-error dbfile $dbc_dumpfile
	db_input critical $dbc_package/upgrade-error || true
	db_go || true
        db_get $dbc_package/upgrade-error
        _dbc_on_error_option="$RET"

        if [ "$_dbc_on_error_option" = "abort" ]; then
			dbc_abort
        fi

        if [ "$_dbc_on_error_option" = "retry" ]; then
        	# forget that we've seen all the debconf questions
        	for f in $dbc_register_templates; do
               		db_fset $dbc_package/$f seen false
        	done
		echo "dbconfig-common: $dbc_package $dbc_command: retrying." >&2
                . /usr/share/dbconfig-common/dpkg/config
                dbc_go $dbc_package configure $dbc_oldversion
                . /usr/share/dbconfig-common/dpkg/postinst
		dbc_go $dbc_package $dbc_command $dbc_oldversion
		dbc_tried_again="yes"
        fi

	if [ "$_dbc_on_error_option" = "retry (skip questions)" ]; then
		echo "dbconfig-common: $dbc_package $dbc_command: trying again." >&2
                . /usr/share/dbconfig-common/dpkg/postinst
		dbc_go $dbc_package $dbc_command $dbc_oldversion 
		dbc_tried_again="yes"
	fi
}

##
## what to do when something goes wrong during remove
##
dbc_remove_error(){
	echo "error encountered $1:" >&2
	echo $dbc_error >&2
	db_fset $dbc_package/remove-error seen false
	db_subst $dbc_package/remove-error error $dbc_error
	db_input critical $dbc_package/remove-error || true
	db_go || true

        db_get $dbc_package/remove-error
        _dbc_on_error_option="$RET"

	if [ "$_dbc_on_error_option" = "abort" ]; then
		dbc_abort
	fi

	if [ "$_dbc_on_error_option" = "retry" ]; then
		# forget that we've seen all the debconf questions
		for f in $dbc_register_templates; do
			db_fset $dbc_package/$f seen false
		done
		echo "dbconfig-common: $dbc_package $dbc_command: retrying." >&2
		. /usr/share/dbconfig-common/dpkg/config
		dbc_go $dbc_package configure $dbc_oldversion
		. /usr/share/dbconfig-common/dpkg/postinst
		dbc_go $dbc_package $dbc_command $dbc_oldversion
		dbc_tried_again="yes"
	fi
}

##
## exactly what you'd think
##
dbc_forget_dbadmin_password(){
	_dbc_debug "dbc_forget_dbadmin_password() $@"
	echo dbconfig-common: flushing administrative password >&2
	db_reset $dbc_package/$dbc_dbtype/admin-pass || true
	db_fset $dbc_package/$dbc_dbtype/admin-pass seen false || true
	db_reset $dbc_package/password-confirm || true
	db_fset $dbc_package/password-confirm seen false || true
}

##
## exactly what you'd think
##
dbc_forget_app_password(){
	_dbc_debug "dbc_forget_app_password() $@"
	db_reset $dbc_package/$dbc_dbtype/app-pass || true
	db_fset $dbc_package/$dbc_dbtype/app-pass seen false || true
	db_reset $dbc_package/app-password-confirm || true
	db_fset $dbc_package/app-password-confirm seen false || true
}

##
## exactly what you'd think
##
##	usage: dbc_get_admin_pass package dbtype
##
dbc_get_admin_pass(){
	local have_admin_pass pass1
	_dbc_debug "dbc_get_admin_pass() $@"

	db_fget $dbc_package/$dbc_dbtype/admin-pass seen 
	if [ "$RET" = "true" ]; then
		have_admin_pass="yes"
	fi

	# make sure the passwords are the same, safely
	while [ ! "$have_admin_pass" ]; do
		# get the administrative password
		db_input high $dbc_package/$dbc_dbtype/admin-pass || true
		db_go || true
		db_get $dbc_package/$dbc_dbtype/admin-pass
		pass1="$RET"

		if [ "$dbc_dbtype" = "pgsql" ] && [ ! "$pass1" ]; then
			db_input high $dbc_package/pgsql/no-empty-passwords || true
			db_reset $dbc_package/$dbc_dbtype/admin-pass
			db_fset $dbc_package/$dbc_dbtype/admin-pass seen false
			db_go || true
		else
			have_admin_pass="yes"
		fi
	done

	db_get $dbc_package/$dbc_dbtype/admin-pass
	dbc_dbadmpass="$RET"
}

##
## exactly what you'd think
##
##	usage: dbc_get_app_pass package dbtype
##
dbc_get_app_pass(){
	local have_app_pass pass1 pass2
	_dbc_debug "dbc_get_app_pass() $@"

	db_fget $dbc_package/$dbc_dbtype/app-pass seen 
	if [ "$RET" = "true" ]; then
		have_app_pass="yes"
		db_get $dbc_package/$dbc_dbtype/app-pass
		dbc_dbpass="$RET"
	fi

	# make sure the passwords are the same, safely
	while [ ! "$have_app_pass" ]; do
		# forget the password-confirm question first, as it's shared
		db_reset $dbc_package/app-password-confirm
		db_fset $dbc_package/app-password-confirm seen false

		# get the appistrative password
		db_input high $dbc_package/$dbc_dbtype/app-pass || true
		db_go || true
		db_get $dbc_package/$dbc_dbtype/app-pass
		pass1="$RET"

		# get the password again, if it is not empty
		if [ "$pass1" ]; then
			db_input high $dbc_package/app-password-confirm || true
			db_go || true
			db_get $dbc_package/app-password-confirm
			pass2="$RET"
		fi

		# test to see if the passwords match
		if [ "$pass1" = "$pass2" ]; then
			dbc_dbpass="$pass1"
			have_app_pass="yes"
		else
			# tell them the passwords didn't match, loop again
			db_reset $dbc_package/$dbc_dbtype/app-pass
			db_fset $dbc_package/$dbc_dbtype/app-pass seen false
			db_input high $dbc_package/passwords-do-not-match || true
			db_go || true
		fi
	done

	if [ ! "$dbc_dbpass" ]; then
		dbc_dbpass=`env LANG=C LC_ALL=C tr -dc "[:alnum:]" < /dev/urandom | dd bs=1 count=12 2>/dev/null`
		db_set $dbc_package/$dbc_dbtype/app-pass "$dbc_dbpass"
		db_set $dbc_package/app-password-confirm "$dbc_dbpass"
	fi
}

##
## perform any necessary cleanup before exiting the postinst
##
dbc_postinst_cleanup(){
	_dbc_debug "dbc_postinst_cleanup() $@"
	if echo "$dbc_authenticated_dbtypes" | grep -q "$dbc_dbtype"; then
		if [ "$dbc_remember_admin_pass" != "true" ]; then
			dbc_forget_dbadmin_password
		fi
		if [ "$dbc_remember_app_pass" != "true" ]; then
			dbc_forget_app_password
		fi
	fi
	db_reset $dbc_package/internal/skip-preseed
}

##
## determine whether a db is supported by a package
##
dbc_detect_supported_dbtype(){
	local query_dbtype
	_dbc_debug "dbc_detect_supported_dbtype() $@"
	query_dbtype=$1
	# see if the package says it's supported
	if echo $dbc_dbtypes | grep -qE "(^|,[[:space:]]*)$query_dbtype(\$|,)"; then
		return 0
	fi
	return 1
}

##
## determine whether a db is installed on the system
##
dbc_detect_installed_dbtype(){
	_dbc_debug "dbc_detect_installed_dbtype() $@"
	_dbc_detect_installed_dbtype $@
}

###
### register all the necessary debconf templates
###
dbc_register_debconf(){
	local f local
	_dbc_debug "dbc_register_debconf() $@"

	for f in $dbc_register_templates; do
		# register the question, but bail if it doesn't (yet) exist
		# failure is gracefully handled elsewhere
		if ! db_register dbconfig-common/$f $dbc_package/$f >/dev/null 2>&1; then
			return 1
		fi
		# perform some basic customizing substitutions
		if [ "$dbc_packagetitle" ]; then
			db_subst $dbc_package/$f pkg $dbc_packagetitle
		else
			db_subst $dbc_package/$f pkg $dbc_package
		fi
		if [ "$dbc_dbvendor" ]; then
			db_subst $dbc_package/$f dbvendor $dbc_dbvendor
		fi
	done
	if [ "$dbc_dbtypes" ]; then
		db_subst $dbc_package/database-type database_types $dbc_dbtypes
	fi
}

###
### dbc_sq_escape: escape any single quotes present in a string
###
###	this will safely escape a string which is to be stored inside
### single quotes.  that is  as'df -> as'\''df
###
dbc_sq_escape(){
	sed -e "s,','\\\\'',g" << EOF
$@
EOF
}
