Class: FFI::Bitmask
- Defined in:
- lib/rubypitaya/app-template/vendor/bundle/ruby/3.1.0/gems/ffi-1.15.5/lib/ffi/enum.rb
Overview
Represents a C enum whose values are power of 2
Contrary to classical enums, bitmask values are usually combined when used.
Instance Attribute Summary
Attributes inherited from Enum
Instance Method Summary collapse
-
#[](*query) ⇒ Object
Get a symbol list or a value from the bitmask.
-
#from_native(val, ctx) ⇒ Array<Symbol, Integer>
List of symbol names corresponding to val, plus an optional remainder if some bits don’t match any constant.
-
#initialize(*args) ⇒ Bitmask
constructor
A new instance of Bitmask.
-
#to_native(query, ctx) ⇒ Object
Get the native value of a bitmask.
Methods inherited from Enum
Methods included from DataConverter
Constructor Details
#initialize(info, tag = nil) ⇒ Bitmask #initialize(native_type, info, tag = nil) ⇒ Bitmask
Returns a new instance of Bitmask.
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# File 'lib/rubypitaya/app-template/vendor/bundle/ruby/3.1.0/gems/ffi-1.15.5/lib/ffi/enum.rb', line 193 def initialize(*args) @native_type = args.first.kind_of?(FFI::Type) ? args.shift : Type::INT info, @tag = *args @kv_map = Hash.new unless info.nil? last_cst = nil value = 0 info.each do |i| case i when Symbol raise ArgumentError, "duplicate bitmask key" if @kv_map.has_key?(i) @kv_map[i] = 1 << value last_cst = i value += 1 when Integer raise ArgumentError, "bitmask index should be positive" if i<0 @kv_map[last_cst] = 1 << i value = i+1 end end end @vk_map = @kv_map.invert end |
Instance Method Details
#[](*query) ⇒ Integer #[](query) ⇒ Integer #[](*query) ⇒ Array<Symbol> #[](query) ⇒ Array<Symbol>
Get a symbol list or a value from the bitmask
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# File 'lib/rubypitaya/app-template/vendor/bundle/ruby/3.1.0/gems/ffi-1.15.5/lib/ffi/enum.rb', line 236 def [](*query) flat_query = query.flatten raise ArgumentError, "query should be homogeneous, #{query.inspect}" unless flat_query.all? { |o| o.is_a?(Symbol) } || flat_query.all? { |o| o.is_a?(Integer) || o.respond_to?(:to_int) } case flat_query[0] when Symbol flat_query.inject(0) do |val, o| v = @kv_map[o] if v then val |= v else val end end when Integer, ->(o) { o.respond_to?(:to_int) } val = flat_query.inject(0) { |mask, o| mask |= o.to_int } @kv_map.select { |_, v| v & val != 0 }.keys end end |
#from_native(val, ctx) ⇒ Array<Symbol, Integer>
Returns list of symbol names corresponding to val, plus an optional remainder if some bits don’t match any constant.
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# File 'lib/rubypitaya/app-template/vendor/bundle/ruby/3.1.0/gems/ffi-1.15.5/lib/ffi/enum.rb', line 282 def from_native(val, ctx) list = @kv_map.select { |_, v| v & val != 0 }.keys # If there are unmatch flags, # return them in an integer, # else information can be lost. # Similar to Enum behavior. remainder = val ^ list.inject(0) do |tmp, o| v = @kv_map[o] if v then tmp |= v else tmp end end list.push remainder unless remainder == 0 return list end |
#to_native(query, ctx) ⇒ Integer #to_native(query, ctx) ⇒ Integer
Get the native value of a bitmask
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# File 'lib/rubypitaya/app-template/vendor/bundle/ruby/3.1.0/gems/ffi-1.15.5/lib/ffi/enum.rb', line 260 def to_native(query, ctx) return 0 if query.nil? flat_query = [query].flatten flat_query.inject(0) do |val, o| case o when Symbol v = @kv_map[o] raise ArgumentError, "invalid bitmask value, #{o.inspect}" unless v val |= v when Integer val |= o when ->(obj) { obj.respond_to?(:to_int) } val |= o.to_int else raise ArgumentError, "invalid bitmask value, #{o.inspect}" end end end |