Merge lp:~smoser/cloud-utils/trunk.1715994-drop-lxd into lp:cloud-utils

[Scott Moser]

mount-image-callback: Drop support for mounting lxd containers.

The 'lxd:' support in mount-image-callback only worked in some cases,
and then stopped working in all cases with lxc 2.17.

This drops the lxd support, but leaves in the 'mchroot' support which
came with it.

[lp:~smoser/cloud-utils/trunk.1715994-drop-lxd]

318. By Scott Moser on 2018-01-03

better unsupported message

319. By Scott Moser on 2018-01-03

merge with trunk

=== modified file 'bin/mount-image-callback'
--- bin/mount-image-callback	2017-02-10 20:30:56 +0000
+++ bin/mount-image-callback	2018-01-03 14:53:10 +0000
@@ -17,7 +17,6 @@
    invoke the provided cmd with args
 
    supported 'file' are:
-      lxd:name  : the rootfs for lxd container 'name'
       file      : any disk format supported by qemu-nbd
 
    the temporary mountpoint will be put in an a environment variable
@@ -159,37 +158,13 @@
 	local d="$1"
 	local umap="$1" gmap="$2"
 	[ -d "$1" ] || mkdir -p "$1"
-	add_bin "$d/uns-switch" <<"EOF" || return 1
-#!/bin/sh
-[ $# -eq 0 ] && set -- ${SHELL:-/bin/bash}
-if [ -z "$MIC_SUBUID" -a -z "$MIC_SUBGID" ]; then
-	exec "$@"
-fi
-exec lxc-usernsexec ${MIC_SUBUID:+-m u:0:${MIC_SUBUID}} \
-	${MIC_SUBGID:+-m g:0:${MIC_SUBGID}} -- "$@"
-EOF
 	add_bin "$d/mchroot" <<"EOF" || return 1
 #!/bin/sh
-exec uns-switch chroot "$MOUNTPOINT" "$@"
+exec chroot "$MOUNTPOINT" "$@"
 EOF
 	return
 }
 
-get_subid() {
-	local id="$1" file="$2"
-	awk -F: '$1 == id { printf("%s:%s\n", $2, $3); exit(0); }' \
-		id="$id" "$file"
-}
-
-set_subids() {
-	local id="$1" out="" muid="" mgid=""
-	[ -z "$id" ] && return 0
-	muid=$(get_subid "$id" /etc/subuid) &&
-		mgid=$(get_subid "$id" /etc/subgid) &&
-		[ -n "$muid" -a -n "$mgid" ] &&
-		export MIC_SUBGID="$muid" MIC_SUBUID="$mgid" && return
-}
-
 mount_overlay() {
 	local lower="$1" upper="$2" workdir="$3"
 	local olayopts="lowerdir=$lower,upperdir=$upper"
@@ -396,38 +371,18 @@
 		return 1;
 	}
 
-	local uns_switch=false
 	img_in="$1"
 	shift 1
 
-	case "$img_in" in
-		lxd:*)
-			if [ "$ptnum" != "auto" ]; then
-				error "--ptnum incompatible with directory"
-				return 1;
-			fi
-			command -v lxc-usernsexec >/dev/null 2>&1 || {
-				error "lxd support needs lxc-usernsexec"; 
-				return 1;
-			}
-			img="/var/lib/lxd/containers/${img_in#lxd:}/rootfs"
-			[ -d "$img" ] || {
-				error "${img_in}: no rootfs in $img. Not a container?"
-				return 1;
-			}
-			set_subids lxd || {
-				error "failed reading subids for lxd";
-				return 1;
-			}
-			uns_switch=true
-			;;
-		*)
-			img=$(readlink -f "$img_in") ||
-				{ error "failed to get full path to $img_in"; return 1; }
-			[ -f "$img" ] ||
-				{ error "$img: not a file"; return 1; }
-			;;
-	esac
+	if [ "${img_in#lxd:}" != "${img_in}" -a ! -f "${img_in}" ]; then
+		error "${img_in}: lxd is no longer supported."
+		return 1;
+	fi
+
+	img=$(readlink -f "$img_in") ||
+		{ error "failed to get full path to $img_in"; return 1; }
+	[ -f "$img" ] ||
+		{ error "$img: not a file"; return 1; }
 
 	[ "$(id -u)" = "0" ] ||
 		{ error "sorry, must be root"; return 1; }
@@ -454,16 +409,7 @@
 	fi
 
 	out=""
-	if [ -d "$img" ]; then
-		debug 1 "using directory at $img for $img_in"
-		mp=$img
-		if $overlay; then
-			debug 1 "mounting $img to $mp"
-			mount --bind "$img" "$img_mp" ||
-				{ error "failed to mount --bind '$img' '$mp'"; return 1; }
-			UMOUNTS[${#UMOUNTS[@]}]="$mp"
-		fi
-	elif [ "$ptnum" = "auto" -o "$ptnum" = "0" ] &&
+	if [ "$ptnum" = "auto" -o "$ptnum" = "0" ] &&
 		out=$(set -f; mount -o "loop,$rwmode" $opts "$img" "$img_mp" 2>&1); then
 		debug 1 "mounted simple filesystem image $rwmode in '$img_in'"
 		UMOUNTS[${UMOUNT[@]}]="$img_mp"
@@ -530,13 +476,6 @@
 		error "MOUNTPOINT=$mp"
 	fi
 
-	if $uns_switch && [ "$1" = "chroot" ]; then
-		debug 1 "added helper uns-switch for chroot"
-		cmd=( uns-switch "${cmd[@]}" )
-	elif $uns_switch; then
-		debug 1 "uns-switch helper can be used for changing user map"
-	fi
-
 	add_helpers "$TEMP_D/bin" "$SUBUID" "$SUBGID" || {
 		error "failed to add helpers to $TEMP_D";
 		return 1;