#! /bin/sh

umask 022

# postmulti(1) contract:
#
# Arguments:
#  postmulti-script -e <edit_command>
#
# Environment:
#
# All actions:
#
#  MAIL_CONFIG			- config_directory of primary instance
#  command_directory		- From primary instance
#  daemon_directory		- From primary instance
#  meta_directory		- From primary instance
#  shlib_directory		- From primary instance
#  config_directroy		- config_directory of target instance
#  queue_directory		- queue_directory of target instance
#  data_directory		- data_directory of target instance
#
# Create, destroy, import and deport:
#
#  multi_instance_directories	- New value for primary instance
#
# Create, import and assign (unset == nochange, "-" == clear):
#
#  multi_instance_group		- New value for target instance
#  multi_instance_name		- New value for target instance

: ${MAIL_CONFIG:?"do not invoke this command directly"}
: ${command_directory:?"do not invoke this command directly"}
: ${daemon_directory:?"do not invoke this command directly"}
: ${meta_directory:?"do not invoke this command directly"}
: ${shlib_directory:?"do not invoke this command directly"}

USAGE="$0 -e create|destroy|import|deport|enable|disable|assign|init"
usage() { echo "$0: Error: Usage: $USAGE" >&2; exit 1; }

TAG="$MAIL_LOGTAG/postmulti-script"
fatal() { postlog -p fatal -t "$TAG" "$1"; exit 1; }

# args: add|del $dir
#
update_cfdirs() {
    op=$1
    dir=$2

    alt=`postconf -h alternate_config_directories` || return 1

    shift $#	# Needed on SunOS where bare "set --" is NOP!
    IFS="$IFS,"; set -- $alt; IFS="$BACKUP_IFS"
    keep=
    found=
    # Portability: SunOS "sh" needs 'in "$@"' for one-line for-loop.
    for d in "$@"; do [ "$d" = "$dir" ] && found=1 || keep="$keep $d"; done

    set -- "multi_instance_directories = $multi_instance_directories"

    case $op in
    add) test -n "$found" ||
	 set -- "$@" "alternate_config_directories =$keep $dir";;
    del) test -n "$found" &&
	 set -- "$@" "alternate_config_directories =$keep";;
      *) return 1;;		# XXX: Internal error
    esac
    postconf -e "$@" || return 1
}

assign_names() {
    # Set the instance name and group
    #
    test -n "$multi_instance_name" && {
	test "$multi_instance_name" = "-" && multi_instance_name=
	set -- "$@" "multi_instance_name = $multi_instance_name"
    }
    test -n "$multi_instance_group" && {
	test "$multi_instance_group" = "-" && multi_instance_group=
	set -- "$@" "multi_instance_group = $multi_instance_group"
    }
    test $# -eq 0 || postconf -c "$config_directory" -e "$@" || return 1
}

# Process command-line options and parameter settings. Work around
# brain damaged shells. "IFS=value command" should not make the
# IFS=value setting permanent. But some broken standard allows it.

BACKUP_IFS="$IFS"
action=

while getopts ":e:" opt
do
    case $opt in
    e) action="$OPTARG";;
    *) usage;;
    esac
done
shift `expr $OPTIND - 1`

# Check for valid action and required instance name
case "$action" in
 create|import|destroy|deport|enable|disable|assign|init) ;;
						       *) usage;;
esac
test $# -eq 0 || usage

case $action in
init)
    postconf -e \
    	'multi_instance_wrapper = ${command_directory}/postmulti -p --' \
    	'multi_instance_enable = yes'
    exit $? ;;
esac

# Backport note: "-x" requires 2.10 or later, and is not essential here.
#
wrapper=`postconf -hx multi_instance_wrapper` || exit 1
enable=`postconf -hx multi_instance_enable` || exit 1

test -n "$wrapper" ||
    fatal "multi_instance_wrapper is empty, run 'postmulti -e init' first."

test "$enable" = "yes" ||
    fatal "multi_instance_enable!=yes, run 'postmulti -e init' first."

: ${config_directory:?"Invalid empty target instance config_directory"}

case $action in
create|import)

    # Atomically install stock main.cf/master.cf files. We install the
    # master.cf file last. Once it is present the instance is complete.
    #
    test -f $config_directory/main.cf -a \
	 -f $config_directory/master.cf || {

	test "$action" = "create" || {
	    test -f $config_directory/main.cf ||
		fatal "'$config_directory' lacks a main.cf file"
	    test -f $config_directory/master.cf ||
		fatal "'$config_directory' lacks a master.cf file"
	}

	test -f $meta_directory/main.cf.proto ||
	    fatal "Missing main.cf prototype: $meta_directory/main.cf.proto"
	test -f $meta_directory/master.cf.proto ||
	    fatal "Missing master.cf prototype: $meta_directory/master.cf.proto"

	# Create instance-specific directories
	#
	test -d $config_directory ||
	    { (umask 022; mkdir -p $config_directory) || exit 1; }
	test -d $queue_directory ||
	    { (umask 022; mkdir -p $queue_directory) || exit 1; }
	test -d $data_directory ||
	    { (umask 077; mkdir -p $data_directory) || exit 1; }

	tmpdir=$config_directory/.tmp
	(umask 077; mkdir -p $tmpdir) || exit 1
	cp -p $meta_directory/main.cf.proto $tmpdir/main.cf || exit 1

	# Shared install parameters are cloned from user-specified values in
	# the default instance, but only if explicitly set there. Otherwise,
	# they are commented out in the new main.cf file.
	#
	SHARED_PARAMETERS="
	    command_directory
	    daemon_directory
	    meta_directory
	    mail_owner
	    setgid_group
	    sendmail_path
	    mailq_path
	    newaliases_path
	    html_directory
	    manpage_directory
	    sample_directory
	    readme_directory
	    shlib_directory
	"

	shift $#	# Needed on SunOS where bare "set --" is NOP!
	comment_out=
	for p in $SHARED_PARAMETERS; do
	    val=`postconf -nh $p` || exit 1
	    test -n "$val" && { set -- "$@" "$p = $val"; continue; }
	    comment_out="$comment_out $p"
	done

	# First comment-out any parameters that take default values
	test -n "$comment_out" && {
	    postconf -c $tmpdir -# $comment_out || exit 1
	}

	# Now add instance-specific and non-default values.
	# By default, disable inet services and local submission
	# in new instances
	#
	postconf -c $tmpdir -e \
	    "queue_directory = $queue_directory" \
	    "data_directory = $data_directory" \
	    "authorized_submit_users =" \
	    "master_service_disable = inet" \
	    "$@" || exit 1


	cp -p $meta_directory/master.cf.proto $tmpdir/master.cf || exit 1
	mv $tmpdir/main.cf $config_directory/main.cf || exit 1
	mv $tmpdir/master.cf $config_directory/master.cf || exit 1
	rmdir $tmpdir 2>/dev/null
    }

    # Set instance name and group
    #
    assign_names || exit 1

    # Update multi_instance_directories
    # and drop from alternate_config_directories
    #
    # XXX: Must happen before set-permissions below, otherwise instance
    # is treated as a non-slave instance by post-install via postfix(1).
    #
    update_cfdirs del $config_directory || exit 1

    # Update permissions of private files. Verifies existence of
    # queue_directory and data_directory, ...
    #
    # XXX: Must happen after instance list updates above, otherwise instance
    # is treated as a non-slave instance by post-install via postfix(1).
    #
    postfix -c $config_directory set-permissions || exit 1
    ;;

deport)
    # Deporting an already deleted instance?
    #
    [ -f "$config_directory/main.cf" ] || {
	update_cfdirs del $config_directory
	exit $?
    }

    postfix -c "$config_directory" status >/dev/null 2>&1 &&
    	fatal "Instance '$config_directory' is not stopped"

    # Update multi_instance_directories
    # and add to alternate_config_directories
    #
    update_cfdirs add $config_directory || exit 1
    ;;

destroy)

    # "postmulti -e destroy" will remove an entire instance only when
    # invoked immediately after "postmulti -e create" (i.e. before
    # other files are added to the instance). We delete only known
    # safe names without "/".
    #
    QUEUE_SUBDIRS="active bounce corrupt defer deferred flush hold \
    incoming maildrop pid private public saved trace"
    #DEBUG=echo
    WARN="postlog -p warn -t $TAG"

    # Locate the target instance
    #
    [ -f "$config_directory/main.cf" ] ||
	fatal "$config_directory/main.cf file not found"

    postfix -c "$config_directory" status >/dev/null 2>&1 &&
    	fatal "Instance '$config_directory' is not stopped"

    # Update multi_instance directories
    # and also (just in case) drop from alternate_config_directories
    #
    $DEBUG update_cfdirs del "$config_directory" || exit 1

    # XXX: Internal "postfix /some/cmd" interface.
    #
    postfix -c "$config_directory" /bin/sh -c "
    for q in $QUEUE_SUBDIRS
    do
	$DEBUG rmdir -- \$q || 
	    $WARN \`pwd\`/\$q: please verify contents and remove by hand
    done
    "

    postfix -c "$config_directory" /bin/sh -c "
    for dir in \$data_directory \$queue_directory
    do
	$DEBUG rmdir -- \$dir || 
	    $WARN \$dir: please verify contents and remove by hand
    done
    "

    # In the configuration directory remove just the main.cf and master.cf
    # files.
    $DEBUG rm -f -- "$config_directory/master.cf" "$config_directory/main.cf" 2>/dev/null
    $DEBUG rmdir -- "$config_directory" || 
	$WARN $config_directory: please verify contents and remove by hand
    ;;

enable)
    postconf -c "$config_directory" -e \
    	"multi_instance_enable = yes" || exit 1;;
disable)
    postconf -c "$config_directory" -e \
    	"multi_instance_enable = no" || exit 1;;
assign)
    assign_names || exit 1;;
esac

exit 0