[Libguestfs] [PATCH v2 2/3] New APIs: part_set_gpt_attributes and part_get_gpt_attributes

[Richard W.M. Jones]

On Mon, Jan 15, 2018 at 03:14:00PM +0100, Cédric Bosdonnat wrote:
> Allow reading and setting the GPT partition attribute flags.
> ---
>  daemon/parted.ml          | 23 +++++++++++++++++++++++
>  daemon/parted.mli         |  3 +++
>  generator/actions_core.ml | 37 +++++++++++++++++++++++++++++++++++++
>  generator/proc_nr.ml      |  2 ++
>  lib/MAX_PROC_NR           |  2 +-
>  5 files changed, 66 insertions(+), 1 deletion(-)
> 
> diff --git a/daemon/parted.ml b/daemon/parted.ml
> index 6fe803613..e3ab823bd 100644
> --- a/daemon/parted.ml
> +++ b/daemon/parted.ml
> @@ -124,10 +124,30 @@ let part_get_parttype device =
>    | _ ->
>       failwithf "%s: cannot parse the output of parted" device
>  
> +let part_set_gpt_attributes device partnum attributes =
> +  if partnum <= 0 then failwith "partition number must be >= 1";
> +
> +  udev_settle ();
> +
> +  let hex = Printf.sprintf "%LX" attributes in
> +  let arg = string_of_int partnum ^ ":=:" ^ hex in

You could write these two lines more simply and clearly as:

  let arg = sprintf "%d:=:%LX" partnum attributes in

You will also need to add ‘open Printf’ after ‘open Scanf’ at the top
of the file so that all the Printf.* functions are available without
needing to be prefixed.

> diff --git a/daemon/parted.mli b/daemon/parted.mli
> index cbcb7b503..9f57bbac7 100644
> --- a/daemon/parted.mli
> +++ b/daemon/parted.mli
> @@ -30,3 +30,6 @@ val part_get_parttype : string -> string
>  
>  val part_get_gpt_type : string -> int -> string
>  val part_get_gpt_guid : string -> int -> string
> +val part_get_gpt_attributes : string -> int -> int64
> +
> +val part_set_gpt_attributes : string -> int -> int64 -> unit

Unnecessary blank line added here?

> diff --git a/generator/actions_core.ml b/generator/actions_core.ml
> index 02759a6b7..78eee61dd 100644
> --- a/generator/actions_core.ml
> +++ b/generator/actions_core.ml
> @@ -8265,6 +8265,43 @@ Return the type GUID of numbered GPT partition C<partnum>. For MBR partitions,
>  return an appropriate GUID corresponding to the MBR type. Behaviour is undefined
>  for other partition types." };
>  
> +  { defaults with
> +    name = "part_set_gpt_attributes"; added = (1, 21, 1);
> +    style = RErr, [String (Device, "device"); Int "partnum"; Int64 "attributes"], [];
> +    impl = OCaml "Parted.part_set_gpt_attributes";
> +    optional = Some "gdisk";
> +    tests = [
> +      InitGPT, Always, TestResult (
> +        [["part_set_gpt_attributes"; "/dev/sda"; "1";
> +          "4"];
> +         ["part_get_gpt_attributes"; "/dev/sda"; "1"]],
> +        "4"), [];
> +    ];
> +    shortdesc = "set the attribute flags of a GPT partition";
> +    longdesc = "\
> +Set the attribute flags of numbered GPT partition C<partnum> to C<attributes>. Return an
> +error if the partition table of C<device> isn't GPT.
> +
> +See L<https://en.wikipedia.org/wiki/GUID_Partition_Table#Partition_entries>
> +for a useful list of partition attributes." };

So we're implicitly importing the ABI of GPT partition attributes into
the libguestfs ABI, which I think is fine as it seems to be
well-defined.

> +  { defaults with
> +    name = "part_get_gpt_attributes"; added = (1, 21, 1);
> +    style = RInt64 "attributes", [String (Device, "device"); Int "partnum"], [];
> +    impl = OCaml "Parted.part_get_gpt_attributes";
> +    optional = Some "gdisk";
> +    tests = [
> +      InitGPT, Always, TestResult (
> +        [["part_set_gpt_attributes"; "/dev/sda"; "1";
> +          "0"];
> +         ["part_get_gpt_attributes"; "/dev/sda"; "1"]],
> +        "4"), [];
> +    ];
> +    shortdesc = "get the attribute flags of a GPT partition";
> +    longdesc = "\
> +Return the attribute flags of numbered GPT partition C<partnum> as a hexadecimal bit mask.

It's not actually returning a "hexadecimal bit mask".  Just remove
that.

Seems fine apart from the changes noted.

Rich.

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