Class: CBOR::Item

Inherits:
Struct
  • Object
show all
Defined in:
lib/libcbor/item.rb

Overview

Wraps native cbor_item_t * to allow extracting Ruby objects

Takes responsibility for high-level native interfacing and object lifetime management.

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#handle ⇒ FFI::Pointer

Native memory handle

Returns:

  • (FFI::Pointer) —

    the current value of handle



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# File 'lib/libcbor/item.rb', line 8

def handle
  @handle
end

Instance Method Details

#type ⇒ Symbol

Type of the underlying item

Returns:



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# File 'lib/libcbor/item.rb', line 12

def type
  LibCBOR.cbor_typeof(handle)
end

#value ⇒ Fixnum, ...

Ruby representation of the CBOR::Item

Arrays and hash maps are constructed recursively

Returns:

  • (Fixnum, String, Float, Array, Map, Tag, TrueClass, FalseClass, NilClass) —

    Value extracted from the #handle



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# File 'lib/libcbor/item.rb', line 21

def value
  case type
    when :uint
      LibCBOR.cbor_get_int(handle)
    when :negint
      -LibCBOR.cbor_get_int(handle) - 1
    when :string
      load_string
    when :bytestring
      load_bytestring
    when :array
      LibCBOR
        .cbor_array_handle(handle)
        .read_array_of_type(LibCBOR::CborItemTRef, :read_pointer, LibCBOR.cbor_array_size(handle))
        .map { |item| Item.new(item).value }
    when :map
      pairs_handle = LibCBOR.cbor_map_handle(handle)
      Hash[LibCBOR.cbor_map_size(handle).times.map { |idx|
        pair = LibCBOR::CborPair.new(pairs_handle + LibCBOR::CborPair.size * idx)
        [pair[:key], pair[:value]].map { |ptr| Item.new(ptr).value }
      }]
    when :tag
      Tag.new(
        LibCBOR.cbor_tag_value(handle),
        Item.new(LibCBOR.cbor_tag_item(handle)).value
      )
    when :float_ctrl
      load_float
    else
      raise 'Unknown type - the FFI enum mapping is probably broken. Please report this bug.'
  end
end