[Libguestfs] [PATCH 2/3] sysprep: Add an optional method for checking if unused arguments were passed to disabled operations.

[Richard W.M. Jones]

---
 sysprep/main.ml               |  6 ++++++
 sysprep/sysprep_operation.ml  | 13 +++++++++++++
 sysprep/sysprep_operation.mli |  9 +++++++++
 3 files changed, 28 insertions(+)

diff --git a/sysprep/main.ml b/sysprep/main.ml
index 5d64538..4919783 100644
--- a/sysprep/main.ml
+++ b/sysprep/main.ml
@@ -221,6 +221,12 @@ read the man page virt-sysprep(1).
   let trace = !trace in
   let verbose = !verbose in
 
+  (* At this point we know which operations are enabled.  So call the
+   * not_enabled_check_args method of all *disabled* operations, so
+   * they have a chance to check for unused command line args.
+   *)
+  Sysprep_operation.not_enabled_check_args ?operations ();
+
   (* Parse the mount options string into a function that maps the
    * mountpoint to the mount options.
    *)
diff --git a/sysprep/sysprep_operation.ml b/sysprep/sysprep_operation.ml
index 19ccfe0..09231cb 100644
--- a/sysprep/sysprep_operation.ml
+++ b/sysprep/sysprep_operation.ml
@@ -43,6 +43,7 @@ type operation = {
   pod_description : string option;
   pod_notes : string option;
   extra_args : extra_arg list;
+  not_enabled_check_args : unit -> unit;
   perform_on_filesystems : filesystem_side_effects callback option;
   perform_on_devices : device_side_effects callback option;
 }
@@ -60,6 +61,7 @@ let defaults = {
   pod_description = None;
   pod_notes = None;
   extra_args = [];
+  not_enabled_check_args = (fun () -> ());
   perform_on_filesystems = None;
   perform_on_devices = None;
 }
@@ -272,6 +274,17 @@ let list_operations () =
         op.heading
   ) !all_operations
 
+let not_enabled_check_args ?operations () =
+  let enabled_ops =
+    match operations with
+    | None -> !enabled_by_default_operations
+    | Some opset -> (* just the operation names listed *)
+      OperationSet.elements opset in
+  let all_ops = opset_of_oplist !all_operations in
+  let enabled_ops = opset_of_oplist enabled_ops in
+  let disabled_ops = OperationSet.diff all_ops enabled_ops in
+  OperationSet.iter (fun op -> op.not_enabled_check_args ()) disabled_ops
+
 let compare_operations { order = o1; name = n1 } { order = o2; name = n2 } =
   let i = compare o1 o2 in
   if i <> 0 then i else compare n1 n2
diff --git a/sysprep/sysprep_operation.mli b/sysprep/sysprep_operation.mli
index c2057ed..d10ef1e 100644
--- a/sysprep/sysprep_operation.mli
+++ b/sysprep/sysprep_operation.mli
@@ -73,6 +73,11 @@ type operation = {
       You can decide the types of the arguments, whether they are
       mandatory etc. *)
 
+  not_enabled_check_args : unit -> unit;
+  (** If the operation is [not] enabled (or disabled), this function is
+      called after argument parsing and can be used to check that
+      no useless extra_args were passed by the user. *)
+
   perform_on_filesystems : filesystem_side_effects callback option;
   (** The function which is called to perform this operation, when
       enabled.
@@ -169,6 +174,10 @@ val remove_all_from_set : set -> set
 (** [remove_all_from_set set] removes from [set] all the available
     operations. *)
 
+val not_enabled_check_args : ?operations:set -> unit -> unit
+(** Call [not_enabled_check_args] on all operations in the set
+    which are {i not} enabled. *)
+
 val perform_operations_on_filesystems : ?operations:set -> verbose:bool -> quiet:bool -> Guestfs.guestfs -> string -> filesystem_side_effects -> unit
 (** Perform all operations, or the subset listed in the [operations] set. *)
 
-- 
2.0.4