From a90682f9819bbbde8717b90498df246bf4650314 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Mon, 1 Jul 2024 11:55:52 +0200
Subject: [PATCH] storagetm: add --list-devices command

---
 man/systemd-storagetm.service.xml | 11 +++++++++++
 src/storagetm/storagetm.c         | 19 +++++++++++++++----
 test/units/TEST-84-STORAGETM.sh   |  2 ++
 3 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/man/systemd-storagetm.service.xml b/man/systemd-storagetm.service.xml
index 6fdbc3dc056..25c5c4e4fc9 100644
--- a/man/systemd-storagetm.service.xml
+++ b/man/systemd-storagetm.service.xml
@@ -90,6 +90,17 @@
 
         <xi:include href="version-info.xml" xpointer="v255"/></listitem>
       </varlistentry>
+
+      <varlistentry>
+        <term><option>--list-devices</option></term>
+
+        <listitem><para>Show a list of candidate block devices this command may operate on. Specifically,
+        this enumerates block devices currently present, and shows their device node paths along with any of
+        their symlinks.</para>
+
+        <xi:include href="version-info.xml" xpointer="v257"/></listitem>
+      </varlistentry>
+
       <xi:include href="standard-options.xml" xpointer="help" />
       <xi:include href="standard-options.xml" xpointer="version" />
     </variablelist>
diff --git a/src/storagetm/storagetm.c b/src/storagetm/storagetm.c
index 1bb8eec3165..910746dc346 100644
--- a/src/storagetm/storagetm.c
+++ b/src/storagetm/storagetm.c
@@ -5,6 +5,7 @@
 
 #include "af-list.h"
 #include "alloc-util.h"
+#include "blockdev-list.h"
 #include "blockdev-util.h"
 #include "build.h"
 #include "daemon-util.h"
@@ -50,6 +51,7 @@ static int help(void) {
                "     --version         Show package version\n"
                "     --nqn=STRING      Select NQN (NVMe Qualified Name)\n"
                "  -a --all             Expose all devices\n"
+               "     --list-devices    List candidate block devices to operate on\n"
                "\nSee the %s for details.\n",
                program_invocation_short_name,
                ansi_highlight(),
@@ -64,13 +66,15 @@ static int parse_argv(int argc, char *argv[]) {
         enum {
                 ARG_NQN = 0x100,
                 ARG_VERSION,
+                ARG_LIST_DEVICES,
         };
 
         static const struct option options[] = {
-                { "help",      no_argument,       NULL, 'h'           },
-                { "version",   no_argument,       NULL, ARG_VERSION   },
-                { "nqn",       required_argument, NULL, ARG_NQN       },
-                { "all",       no_argument,       NULL, 'a'           },
+                { "help",         no_argument,       NULL, 'h'              },
+                { "version",      no_argument,       NULL, ARG_VERSION      },
+                { "nqn",          required_argument, NULL, ARG_NQN          },
+                { "all",          no_argument,       NULL, 'a'              },
+                { "list-devices", no_argument,       NULL, ARG_LIST_DEVICES },
                 {}
         };
 
@@ -102,6 +106,13 @@ static int parse_argv(int argc, char *argv[]) {
                         arg_all++;
                         break;
 
+                case ARG_LIST_DEVICES:
+                        r = blockdev_list(BLOCKDEV_LIST_SHOW_SYMLINKS|BLOCKDEV_LIST_IGNORE_ZRAM);
+                        if (r < 0)
+                                return r;
+
+                        return 0;
+
                 case '?':
                         return -EINVAL;
 
diff --git a/test/units/TEST-84-STORAGETM.sh b/test/units/TEST-84-STORAGETM.sh
index eae87d52341..1dd2ea61849 100755
--- a/test/units/TEST-84-STORAGETM.sh
+++ b/test/units/TEST-84-STORAGETM.sh
@@ -3,6 +3,8 @@
 set -eux
 set -o pipefail
 
+/usr/lib/systemd/systemd-storagetm --list-devices
+
 modprobe -v nvmet-tcp
 modprobe -v nvme-tcp
 
-- 
2.47.3