Commit 26071913 authored by Donald Hunter's avatar Donald Hunter Committed by Jakub Kicinski
Browse files

tools: ynl: Add struct attr decoding to ynl 



Add support for decoding attributes that contain C structs.

Signed-off-by: default avatarDonald Hunter <donald.hunter@gmail.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent b423c3c8

Documentation/netlink/genetlink-legacy.yaml

+5 −0
Original line number Diff line number Diff line
@@ -218,6 +218,11 @@ properties: 
                    description: Max length for a string or a binary attribute.

                    $ref: '#/$defs/len-or-define'

              sub-type: *attr-type

              # Start genetlink-legacy

              struct:

                description: Name of the struct type used for the attribute.

                type: string

              # End genetlink-legacy



      # Make sure name-prefix does not appear in subsets (subsets inherit naming)

      dependencies:

tools/net/ynl/lib/nlspec.py

+2 −0
Original line number Diff line number Diff line
@@ -152,6 +152,7 @@ class SpecAttr(SpecElement): 
        value         numerical ID when serialized

        attr_set      Attribute Set containing this attr

        is_multi      bool, attr may repeat multiple times

        struct_name   string, name of struct definition

        sub_type      string, name of sub type

    """

    def __init__(self, family, attr_set, yaml, value):
@@ -160,6 +161,7 @@ class SpecAttr(SpecElement): 
        self.value = value

        self.attr_set = attr_set

        self.is_multi = yaml.get('multi-attr', False)

        self.struct_name = yaml.get('struct')

        self.sub_type = yaml.get('sub-type')

tools/net/ynl/lib/ynl.py

+14 −1
Original line number Diff line number Diff line
@@ -102,6 +102,17 @@ class NlAttr: 
        format, _ = self.type_formats[type]

        return list({ x[0] for x in struct.iter_unpack(format, self.raw) })



    def as_struct(self, members):

        value = dict()

        offset = 0

        for m in members:

            # TODO: handle non-scalar members

            format, size = self.type_formats[m.type]

            decoded = struct.unpack_from(format, self.raw, offset)

            offset += size

            value[m.name] = decoded[0]

        return value



    def __repr__(self):

        return f"[type:{self.type} len:{self._len}] {self.raw}"
@@ -377,7 +388,9 @@ class YnlFamily(SpecFamily): 
        rsp[attr_spec['name']] = value



    def _decode_binary(self, attr, attr_spec):

        if attr_spec.sub_type:

        if attr_spec.struct_name:

            decoded = attr.as_struct(self.consts[attr_spec.struct_name])

        elif attr_spec.sub_type:

            decoded = attr.as_c_array(attr_spec.sub_type)

        else:

            decoded = attr.as_bin()