test: add integration test for storagectl and storage providers

VM-only test that exercises both shipped providers through storagectl:
verifies the well-known sockets exist, lists providers/volumes/
templates, creates and acquires volumes from each template
(sparse-file, allocated-file, directory, subvolume), attaches a loop
device to cover the block provider, and exercises the mount.storage
helper.

diff --git a/test/units/TEST-87-AUX-UTILS-VM.storagectl.sh b/test/units/TEST-87-AUX-UTILS-VM.storagectl.sh
new file mode 100755 (executable)
index 0000000..a11a952
--- /dev/null
+++ b/test/units/TEST-87-AUX-UTILS-VM.storagectl.sh
@@ -0,0 +1,211 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: LGPL-2.1-or-later
+set -eux
+set -o pipefail
+
+if ! command -v storagectl >/dev/null; then
+    echo "storagectl not found, skipping."
+    exit 77
+fi
+
+# shellcheck source=test/units/util.sh
+. "$(dirname "$0")"/util.sh
+
+# Unset $PAGER so we don't have to use --no-pager everywhere
+export PAGER=
+
+# storagectl runs in a VM-only test
+if systemd-detect-virt -cq ; then
+    echo "can't run in a container, skipping."
+    exit 77
+fi
+
+at_exit() {
+    set +e
+
+    if [[ -n "${MOUNT_DIR:-}" ]] && mountpoint -q "$MOUNT_DIR"; then
+        umount "$MOUNT_DIR"
+    fi
+    if [[ -n "${LOOP:-}" ]]; then
+        systemd-dissect --detach "$LOOP"
+    fi
+    if [[ -n "${WORK_DIR:-}" ]]; then
+        rm -fr "$WORK_DIR"
+    fi
+    rm -fr /var/lib/storage/test-87-storage-*.volume
+}
+trap at_exit EXIT
+
+# The storage providers are socket-activated by sockets.target, so the listening
+# AF_UNIX sockets should already exist.
+test -S /run/systemd/io.systemd.StorageProvider/block
+test -S /run/systemd/io.systemd.StorageProvider/fs
+
+WORK_DIR="$(mktemp -d /tmp/test-storagectl.XXXXXXXXXX)"
+MOUNT_DIR="$WORK_DIR/mnt"
+mkdir -p "$MOUNT_DIR"
+
+# --- storagectl basic ---
+
+storagectl --help
+storagectl --version
+storagectl help
+
+# Unknown verb / option
+(! storagectl this-verb-does-not-exist)
+(! storagectl --no-such-option providers)
+
+# --- storagectl providers ---
+
+storagectl providers
+storagectl providers --no-legend
+storagectl providers --no-pager
+storagectl providers --json=pretty | jq .
+storagectl providers --json=short | jq .
+
+providers_output="$(storagectl providers --no-legend)"
+assert_in 'block' "$providers_output"
+assert_in 'fs'    "$providers_output"
+assert_in 'yes'   "$providers_output"
+
+# --- storagectl volumes ---
+
+# 'volumes' is the default verb
+storagectl
+storagectl volumes
+storagectl volumes --no-legend
+storagectl volumes --no-pager
+storagectl volumes --json=pretty | jq .
+storagectl volumes --json=short  | jq .
+
+# Glob filter that matches nothing should not error
+storagectl volumes 'no-such-volume-*'
+
+# --- storagectl templates ---
+
+storagectl templates
+storagectl templates --no-legend --no-pager
+storagectl templates --json=pretty | jq .
+storagectl templates --json=short  | jq --seq .
+
+templates_output="$(storagectl templates --no-legend)"
+assert_in 'sparse-file'    "$templates_output"
+assert_in 'allocated-file' "$templates_output"
+assert_in 'directory'      "$templates_output"
+assert_in 'subvolume'      "$templates_output"
+
+# Glob filter
+storagectl templates 'sparse-*' --no-legend | grep sparse-file >/dev/null
+(! storagectl templates 'sparse-*' --no-legend | grep allocated-file >/dev/null)
+storagectl templates 'no-such-template-*'
+
+# --- direct varlink calls ---
+
+varlinkctl introspect /run/systemd/io.systemd.StorageProvider/block io.systemd.StorageProvider
+varlinkctl introspect /run/systemd/io.systemd.StorageProvider/fs    io.systemd.StorageProvider
+
+# Block provider does not expose templates
+varlinkctl call --more /run/systemd/io.systemd.StorageProvider/block \
+    io.systemd.StorageProvider.ListTemplates '{}' \
+    --graceful=io.systemd.StorageProvider.NoSuchTemplate
+
+# fs provider lists the four built-in templates
+varlinkctl call --more --json=short /run/systemd/io.systemd.StorageProvider/fs \
+    io.systemd.StorageProvider.ListTemplates '{}' | grep '"name":"sparse-file"' >/dev/null
+
+# Block provider rejects names not under /dev/
+varlinkctl call /run/systemd/io.systemd.StorageProvider/block \
+    io.systemd.StorageProvider.Acquire '{"name":"/tmp/no-such-dev"}' \
+    --graceful=io.systemd.StorageProvider.NoSuchVolume
+
+# fs provider rejects bad volume names (contain '/' → not a valid filename)
+varlinkctl call /run/systemd/io.systemd.StorageProvider/fs \
+    io.systemd.StorageProvider.Acquire '{"name":"bad/name"}' \
+    --graceful=org.varlink.service.InvalidParameter
+
+# --- mount.storage: regular file via fs provider ---
+
+TESTVOL_REG="test-87-storage-reg-$RANDOM"
+truncate -s 32M "/var/lib/storage/$TESTVOL_REG.volume"
+mkfs.ext4 "/var/lib/storage/$TESTVOL_REG.volume"
+mount -t storage.ext4 "fs:$TESTVOL_REG" "$MOUNT_DIR"
+mountpoint -q "$MOUNT_DIR"
+echo "hello reg" >"$MOUNT_DIR/hello"
+umount "$MOUNT_DIR"
+
+# Volume now appears in 'storagectl volumes'
+volumes_after_create="$(storagectl volumes "$TESTVOL_REG" --no-legend)"
+assert_in "$TESTVOL_REG" "$volumes_after_create"
+assert_in 'reg'          "$volumes_after_create"
+
+# Re-mount existing (default storage.create=any)
+mount -t storage.ext4 "fs:$TESTVOL_REG" "$MOUNT_DIR"
+test -f "$MOUNT_DIR/hello"
+umount "$MOUNT_DIR"
+
+# storage.create=open succeeds for existing volume
+mount -t storage.ext4 -o "storage.create=open" "fs:$TESTVOL_REG" "$MOUNT_DIR"
+umount "$MOUNT_DIR"
+
+# storage.create=new on existing volume must fail
+(! mount -t storage.ext4 -o "storage.create=new,storage.create-size=16M" "fs:$TESTVOL_REG" "$MOUNT_DIR")
+
+# Read-only mount
+mount -t storage.ext4 -o ro "fs:$TESTVOL_REG" "$MOUNT_DIR"
+findmnt -n -o options "$MOUNT_DIR" | grep -E '(^|,)ro(,|$)' >/dev/null
+(! touch "$MOUNT_DIR/readonly-test")
+umount "$MOUNT_DIR"
+
+rm -f "/var/lib/storage/$TESTVOL_REG.volume"
+
+# storage.create=open on missing volume must fail
+(! mount -t storage.ext4 -o "storage.create=open" "fs:test-87-storage-missing-$RANDOM" "$MOUNT_DIR")
+
+# --- mount.storage: directory volume via fs provider (requires idmapped mounts) ---
+
+TESTVOL_DIR="test-87-storage-dir-$RANDOM"
+if mount -t storage "fs:$TESTVOL_DIR" "$MOUNT_DIR"; then
+    mountpoint -q "$MOUNT_DIR"
+    test -d "/var/lib/storage/$TESTVOL_DIR.volume/root"
+    echo "dir test" >"$MOUNT_DIR/hello"
+    test -f "/var/lib/storage/$TESTVOL_DIR.volume/root/hello"
+    umount "$MOUNT_DIR"
+    rm -fr "/var/lib/storage/$TESTVOL_DIR.volume"
+else
+    echo "Directory volume mounting failed (idmapped mounts unsupported?), skipping."
+    rm -fr "/var/lib/storage/$TESTVOL_DIR.volume"
+fi
+
+# --- mount.storage: block device via block provider ---
+
+truncate -s 32M "$WORK_DIR/block.img"
+mkfs.ext4 -L sd-storage-blk "$WORK_DIR/block.img"
+LOOP="$(systemd-dissect --attach --loop-ref=test-storagectl "$WORK_DIR/block.img")"
+
+mount -t storage.ext4 "block:$LOOP" "$MOUNT_DIR"
+mountpoint -q "$MOUNT_DIR"
+echo "hello blk" >"$MOUNT_DIR/hello"
+umount "$MOUNT_DIR"
+
+# Read-only mount of the block volume
+mount -t storage.ext4 -o ro "block:$LOOP" "$MOUNT_DIR"
+findmnt -n -o options "$MOUNT_DIR" | grep -E '(^|,)ro(,|$)' >/dev/null
+test -f "$MOUNT_DIR/hello"
+umount "$MOUNT_DIR"
+
+# Block volume is enumerable; matchName globs over device node and aliases
+varlinkctl call --more --json=short /run/systemd/io.systemd.StorageProvider/block \
+    io.systemd.StorageProvider.ListVolumes "{\"matchName\":\"$LOOP\"}" |
+    grep '"type":"blk"' >/dev/null
+
+systemd-dissect --detach "$LOOP"
+unset LOOP
+
+# --- error cases ---
+
+# Bad provider name (no such socket)
+(! mount -t storage.ext4 "no-such-provider:foo" "$MOUNT_DIR")
+# Bad volume specification (no colon)
+(! mount -t storage.ext4 "no-colon-here" "$MOUNT_DIR")
+# Refuse nested storage volumes (FS type "storage.storage")
+(! mount -t storage.storage "fs:something" "$MOUNT_DIR")