Libguestfs - Aug 2019 - [nbdkit PATCH] ocaml: Map more errno values

Mapping of EOVERFLOW was missed in commit 6f8c8084.

Mapping of EOPNOTSUPP is essential for .zero to trigger a fallback to
.pwrite, missed in commit 6c0e00e9 (not to mention that it becomes a
valid protocol failure once fast zero support is added).  There is no
Unix.ENOTSUP, or that would get the same treatment per commit
abb2b47c.

Preserving EROFS and EFBIG is useful because protocol.c special-cases
those (by merging them into EPERM and ENOSPC over the wire).  There is
no Unix.EDQUOT, or that would get the same treatment.

Signed-off-by: Eric Blake <eblake@redhat.com>
---
 plugins/ocaml/ocaml.c   | 7 +++++++
 plugins/ocaml/NBDKit.ml | 4 ++++
 2 files changed, 11 insertions(+)

diff --git a/plugins/ocaml/ocaml.c b/plugins/ocaml/ocaml.c
index 064cdedb..5161775f 100644
--- a/plugins/ocaml/ocaml.c
+++ b/plugins/ocaml/ocaml.c
@@ -849,12 +849,19 @@ ocaml_nbdkit_set_error (value nv)
   int err;

   switch (Int_val (nv)) {
+    /* On-the-wire values */
   case 1: err = EPERM; break;
   case 2: err = EIO; break;
   case 3: err = ENOMEM; break;
   case 4: err = EINVAL; break;
   case 5: err = ENOSPC; break;
   case 6: err = ESHUTDOWN; break;
+  case 7: err = EOVERFLOW; break;
+    /* Necessary for .zero support */
+  case 8: err = ENOTSUP; break;
+    /* Other errno that server/protocol.c treats specially */
+  case 9: err = EROFS; break;
+  case 10: err = EFBIG; break;
   default: abort ();
   }

diff --git a/plugins/ocaml/NBDKit.ml b/plugins/ocaml/NBDKit.ml
index 68d15836..e54a7705 100644
--- a/plugins/ocaml/NBDKit.ml
+++ b/plugins/ocaml/NBDKit.ml
@@ -267,6 +267,10 @@ let set_error unix_error      | Unix.EINVAL     -> 4
     | Unix.ENOSPC     -> 5
     | Unix.ESHUTDOWN  -> 6
+    | Unix.EOVERFLOW  -> 7
+    | Unix.EOPNOTSUPP -> 8
+    | Unix.EROFS      -> 9
+    | Unix.EFBIG      -> 10
     | _               -> 4 (* EINVAL *) in

   _set_error nbd_error
-- 
2.20.1

On Fri, Aug 16, 2019 at 08:29:28AM -0500, Eric Blake
wrote:
> --- a/plugins/ocaml/ocaml.c
> +++ b/plugins/ocaml/ocaml.c
> @@ -849,12 +849,19 @@ ocaml_nbdkit_set_error (value nv)
>    int err;
> 
>    switch (Int_val (nv)) {
> +    /* On-the-wire values */
Not sure about this comment.  The values on the left match the values
in NBDKit.ml's ‘set_error’ function, and are basically internal to the
OCaml bindings.  The values on the right are from <errno.h> and AIUI
they might be unrelated to what is sent on the wire (especially on
non-Linux).

Nevertheless the implementation is still correct, so ACK.

Rich.
>    case 1: err = EPERM; break;
>    case 2: err = EIO; break;
>    case 3: err = ENOMEM; break;
>    case 4: err = EINVAL; break;
>    case 5: err = ENOSPC; break;
>    case 6: err = ESHUTDOWN; break;
> +  case 7: err = EOVERFLOW; break;
> +    /* Necessary for .zero support */
> +  case 8: err = ENOTSUP; break;
> +    /* Other errno that server/protocol.c treats specially */
> +  case 9: err = EROFS; break;
> +  case 10: err = EFBIG; break;
>    default: abort ();
>    }
> 
> diff --git a/plugins/ocaml/NBDKit.ml b/plugins/ocaml/NBDKit.ml
> index 68d15836..e54a7705 100644
> --- a/plugins/ocaml/NBDKit.ml
> +++ b/plugins/ocaml/NBDKit.ml
> @@ -267,6 +267,10 @@ let set_error unix_error >      | Unix.EINVAL    
-> 4
>      | Unix.ENOSPC     -> 5
>      | Unix.ESHUTDOWN  -> 6
> +    | Unix.EOVERFLOW  -> 7
> +    | Unix.EOPNOTSUPP -> 8
> +    | Unix.EROFS      -> 9
> +    | Unix.EFBIG      -> 10
>      | _               -> 4 (* EINVAL *) in
> 
>    _set_error nbd_error
> -- 
> 2.20.1
> 
> _______________________________________________
> Libguestfs mailing list
> Libguestfs@redhat.com
> https://www.redhat.com/mailman/listinfo/libguestfs
-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
Fedora Windows cross-compiler. Compile Windows programs, test, and
build Windows installers. Over 100 libraries supported.
http://fedoraproject.org/wiki/MinGW