[Libguestfs] [nbdkit PATCH] vddk: Make 'file=' a magic key

[Eric Blake]

Since it is required, it might as well be magic ;)

Signed-off-by: Eric Blake <eblake at redhat.com>
---

As written, applies on top of my v3 patch for dlopen; but it would
be easy enough to rebase and take this one now even if we aren't
sure about the dlopen stuff

 plugins/vddk/nbdkit-vddk-plugin.pod | 5 ++++-
 plugins/vddk/vddk.c                 | 3 ++-
 tests/test-vddk.sh                  | 3 +--
 3 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/plugins/vddk/nbdkit-vddk-plugin.pod b/plugins/vddk/nbdkit-vddk-plugin.pod
index f0748def..11d12c3f 100644
--- a/plugins/vddk/nbdkit-vddk-plugin.pod
+++ b/plugins/vddk/nbdkit-vddk-plugin.pod
@@ -4,7 +4,7 @@ nbdkit-vddk-plugin - nbdkit VMware VDDK plugin

 =head1 SYNOPSIS

- nbdkit vddk file=FILENAME
+ nbdkit vddk [file=]FILENAME
              [config=FILENAME] [cookie=COOKIE] [libdir=LIBRARY]
              [nfchostport=PORT] [single-link=true]
              [password=PASSWORD | password=- | password=+FILENAME
@@ -135,6 +135,9 @@ If a VM has multiple disks, nbdkit can only serve one at a time.  To
 serve more than one you must run multiple copies of nbdkit.  (See
 L</NOTES> below).

+C<file=> is a magic config key and may be omitted in most cases.
+See L<nbdkit(1)/Magic parameters>.
+
 =item B<libdir=>PATHNAME

 This sets the path of the VMware VDDK distribution.
diff --git a/plugins/vddk/vddk.c b/plugins/vddk/vddk.c
index 6deb0a0b..344b4e6b 100644
--- a/plugins/vddk/vddk.c
+++ b/plugins/vddk/vddk.c
@@ -416,7 +416,7 @@ vddk_config_complete (void)
 }

 #define vddk_config_help \
-  "file=<FILENAME>     (required) The filename (eg. VMDK file) to serve.\n" \
+  "[file=]<FILENAME>   (required) The filename (eg. VMDK file) to serve.\n" \
   "Many optional parameters are supported, see nbdkit-vddk-plugin(3)."

 static void
@@ -901,6 +901,7 @@ static struct nbdkit_plugin plugin = {
   .config            = vddk_config,
   .config_complete   = vddk_config_complete,
   .config_help       = vddk_config_help,
+  .magic_config_key  = "file",
   .dump_plugin       = vddk_dump_plugin,
   .open              = vddk_open,
   .close             = vddk_close,
diff --git a/tests/test-vddk.sh b/tests/test-vddk.sh
index d99ebf88..6933f716 100755
--- a/tests/test-vddk.sh
+++ b/tests/test-vddk.sh
@@ -48,8 +48,7 @@ grep ^vddk_default_libdir= test-vddk.out
 # a load that we know will fail, but the important part is that dlopen's
 # error message lists an absolute file even though we passed a relative
 # name, showing that our shim did adjust it.
-nbdkit vddk libdir=.libs \
-  file=/dev/null --run ':' 2> test-vddk.err || :
+nbdkit vddk libdir=.libs /dev/null --run ':' 2> test-vddk.err || :
 cat test-vddk.err

 grep '/.libs/nosuch' test-vddk.err
-- 
2.24.1