From: Zbigniew Jędrzejewski-Szmek <zbyszek@amutable.com>
Date: Tue, 3 Mar 2026 15:32:29 +0000 (+0100)
Subject: vmspawn: change order of fields in --extra-drive=
X-Git-Tag: v260-rc2~12
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=a8637c059bf2efb756e8e9e901af0788d381cd62;p=thirdparty%2Fsystemd.git

vmspawn: change order of fields in --extra-drive=

Closes #40877. As requested, --extra-drive=path[:format] is changed
to --extra-drive=[format:]path, so that the parsing is less ambiguous.
(In the original request, it was requested that the empty format can be
used also, but that was dropped in the second version of the patch.)
---

diff --git a/NEWS b/NEWS
index 495f12eda80..82b30951d24 100644
--- a/NEWS
+++ b/NEWS
@@ -329,8 +329,8 @@ CHANGES WITH 260 in spe:
           the same switch in systemd-nspawn.
 
         * systemd-vmspawn gained a new switch --image-format= for selecting the
-          image format (i.e. support qcow2 in additin to raw) to boot
-          from. --extra-drive= now takes the image format as a colon separated
+          image format (i.e. support qcow2 in additin to raw) to boot from.
+          Also --extra-drive= now takes the image format as a colon separated
           parameter.
 
         Changes in systemd-nsresourced/systemd-mountfsd:
diff --git a/man/systemd-vmspawn.xml b/man/systemd-vmspawn.xml
index 0b4fef2314a..136bd653406 100644
--- a/man/systemd-vmspawn.xml
+++ b/man/systemd-vmspawn.xml
@@ -489,12 +489,13 @@
         </varlistentry>
 
         <varlistentry>
-          <term><option>--extra-drive=<replaceable>PATH</replaceable>[:<replaceable>FORMAT</replaceable>]</option></term>
+          <term><option>--extra-drive=[<replaceable>FORMAT</replaceable>:]<replaceable>PATH</replaceable></option></term>
 
           <listitem><para>Takes a disk image or block device on the host and supplies it to the virtual
-          machine as another drive. Optionally, the image format can be specified by appending a colon and
-          the format (<literal>raw</literal> or <literal>qcow2</literal>). Defaults to <literal>raw</literal>.
-          Note that <literal>qcow2</literal> is only supported for regular files, not block devices.</para>
+          machine as another drive. Optionally, the image format can be specified by prefixing the path with
+          <literal>raw</literal> or <literal>qcow2</literal> and a colon. The format defaults to
+          <literal>raw</literal>. Note that <literal>qcow2</literal> is only supported for regular files, not
+          block devices.</para>
 
           <xi:include href="version-info.xml" xpointer="v256"/></listitem>
         </varlistentry>
diff --git a/src/vmspawn/vmspawn.c b/src/vmspawn/vmspawn.c
index d68a621e060..fc647b15638 100644
--- a/src/vmspawn/vmspawn.c
+++ b/src/vmspawn/vmspawn.c
@@ -238,9 +238,9 @@ static int help(void) {
                "                           Mount a file or directory from the host into the VM\n"
                "     --bind-ro=SOURCE[:TARGET]\n"
                "                           Mount a file or directory, but read-only\n"
-               "     --extra-drive=PATH[:FORMAT]\n"
+               "     --extra-drive=[FORMAT:]PATH\n"
                "                           Adds an additional disk to the virtual machine\n"
-               "                           (format: raw, qcow2; default: raw)\n"
+               "                           (FORMAT: raw, qcow2; default: raw)\n"
                "     --bind-user=NAME       Bind user from host to virtual machine\n"
                "     --bind-user-shell=BOOL|PATH\n"
                "                            Configure the shell to use for --bind-user= users\n"
@@ -559,23 +559,26 @@ static int parse_argv(int argc, char *argv[]) {
                         break;
 
                 case ARG_EXTRA_DRIVE: {
-                        _cleanup_free_ char *buf = NULL, *drive_path = NULL;
                         ImageFormat format = IMAGE_FORMAT_RAW;
+                        const char *dp = optarg;
 
-                        const char *colon = strrchr(optarg, ':');
+                        const char *colon = strchr(dp, ':');
                         if (colon) {
-                                ImageFormat f = image_format_from_string(colon + 1);
+                                _cleanup_free_ char *fs = strndup(optarg, colon - optarg);
+                                if (!fs)
+                                        return log_oom();
+
+                                ImageFormat f = image_format_from_string(fs);
                                 if (f < 0)
-                                        log_debug_errno(f, "Failed to parse image format '%s', assuming it is a part of path, ignoring: %m", colon + 1);
+                                        log_debug_errno(f, "Cannot parse '%s' as an image format, assuming it is a part of path, ignoring.", fs);
                                 else {
                                         format = f;
-                                        buf = strndup(optarg, colon - optarg);
-                                        if (!buf)
-                                                return log_oom();
+                                        dp = colon + 1;
                                 }
                         }
 
-                        r = parse_path_argument(buf ?: optarg, /* suppress_root= */ false, &drive_path);
+                        _cleanup_free_ char *drive_path = NULL;
+                        r = parse_path_argument(dp, /* suppress_root= */ false, &drive_path);
                         if (r < 0)
                                 return r;