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

[Cédric Bosdonnat]

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
+  let r, _, err =
+    commandr ~fold_stdout_on_stderr:true
+             "sgdisk" [ device; "-A"; arg ] in
+  if r <> 0 then
+    failwithf "sgdisk: %s" err;
+
+  udev_settle ()
+
 let extract_guid value =
   (* The value contains only valid GUID characters. *)
   String.sub value 0 (String.span value "-0123456789ABCDEF")
 
+let extract_hex value =
+  (* The value contains only valid numeric characters. *)
+  let str = String.sub value 0 (String.span value "0123456789ABCDEF") in
+  Int64.of_string ("0x" ^ str)
+
 let sgdisk_info_extract_field device partnum field extractor =
   if partnum <= 0 then failwith "partition number must be >= 1";
 
@@ -179,3 +199,6 @@ let rec part_get_gpt_type device partnum =
 and part_get_gpt_guid device partnum =
   sgdisk_info_extract_field device partnum "Partition unique GUID"
                             extract_guid
+and part_get_gpt_attributes device partnum =
+  sgdisk_info_extract_field device partnum "Attribute flags"
+                            extract_hex
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
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." };
+
+  { 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.
+For MBR partitions, return all flags set to 0." };
+
   { defaults with
     name = "rename"; added = (1, 21, 5);
     style = RErr, [String (Pathname, "oldpath"); String (Pathname, "newpath")], [];
diff --git a/generator/proc_nr.ml b/generator/proc_nr.ml
index 3e393da73..9e16ab14a 100644
--- a/generator/proc_nr.ml
+++ b/generator/proc_nr.ml
@@ -510,6 +510,8 @@ let proc_nr = [
 500, "inspect_get_mountpoints";
 501, "inspect_get_filesystems";
 502, "inspect_get_drive_mappings";
+503, "part_set_gpt_attributes";
+504, "part_get_gpt_attributes";
 ]
 
 (* End of list.  If adding a new entry, add it at the end of the list
diff --git a/lib/MAX_PROC_NR b/lib/MAX_PROC_NR
index cc5027eed..3091e8eea 100644
--- a/lib/MAX_PROC_NR
+++ b/lib/MAX_PROC_NR
@@ -1 +1 @@
-502
+504
-- 
2.15.1