Class: CrystalRuby::Types::VariableWidth

Inherits:
FixedWidth show all
Defined in:
lib/crystalruby/types/variable_width.rb

Overview

A variable with type operates much like a fixed width type, but it writes a size and a pointer to the type memory instead of the data itself. When we decrement our internal ref count we need to resolve the pointer. The layout is a tiny bit different (data begins at byte 8 to allow room for size uint32 at byte 4)

Constant Summary

Constants inherited from Type

Type::ARC_MUTEX

Constants included from CrystalRuby::Typemaps

CrystalRuby::Typemaps::CRYSTAL_TYPE_MAP, CrystalRuby::Typemaps::C_TYPE_CONVERSIONS, CrystalRuby::Typemaps::C_TYPE_MAP, CrystalRuby::Typemaps::ERROR_VALUE, CrystalRuby::Typemaps::FFI_TYPE_MAP

Instance Attribute Summary

Attributes inherited from Type

#memory, #value

Class Method Summary collapse

Methods inherited from FixedWidth

#address, #allocate_new_from_reference!, #allocate_new_from_value!, crystal_type, #data_pointer, decr_inner_ref_counts!, decrement_ref_count!, fetch_multi, fetch_single, finalize, free!, increment_ref_count!, #initialize, #ref_count, #ref_count=, #size, to_ffi_repr, #value=, write_single

Methods inherited from Type

#==, [], anonymous?, base_crystal_class_name, bind_local_vars!, cast!, #coerce, crystal_class_name, crystal_type, crystal_type_to_pointer_type_conversion, #deep_dup, #dup, each_child_address, finalize, fixed_width?, from_ffi_array_repr, #initialize, inner_type, #inner_value, inspect, #inspect, inspect_name, #item_size, #method_missing, #native, native_type_expr, nested_types, #nil?, numeric?, pointer_to_crystal_type_conversion, primitive?, template_name, type_defn, type_digest, type_expr, union_types, valid?, valid_cast?, validate!, |

Methods included from CrystalRuby::Typemaps

#build_type_map, #convert_crystal_to_lib_type, #convert_lib_to_crystal_type, #crystal_type, #error_value, #ffi_type, #lib_type

Methods included from Allocator

included

Constructor Details

This class inherits a constructor from CrystalRuby::Types::FixedWidth

Dynamic Method Handling

This class handles dynamic methods through the method_missing method in the class CrystalRuby::Types::Type

Class Method Details

.build(typename = nil, error: nil, inner_types: nil, inner_keys: nil, ffi_type: :pointer, size_offset: 4, data_offset: 8, memsize: FFI.type_size(ffi_type), refsize: 8, convert_if: [], superclass: VariableWidth, &block) ⇒ Object 



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# File 'lib/crystalruby/types/variable_width.rb', line 16

def self.build(
  typename = nil,
  error: nil,
  inner_types: nil,
  inner_keys: nil,
  ffi_type: :pointer,
  size_offset: 4,
  data_offset: 8,
  memsize: FFI.type_size(ffi_type),
  refsize: 8,
  convert_if: [],
  superclass: VariableWidth,
  &block
)
  inner_types&.each(&Type.method(:validate!))

  Class.new(superclass) do
    bind_local_vars!(
      %i[typename error inner_types inner_keys ffi_type memsize convert_if data_offset size_offset
         refsize], binding
    )
    class_eval(&block) if block_given?
  end
end

.crystal_supertype ⇒ Object 



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# File 'lib/crystalruby/types/variable_width.rb', line 12

def self.crystal_supertype
  "CrystalRuby::Types::VariableWidth"
end

.variable_width? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/crystalruby/types/variable_width.rb', line 8

def self.variable_width?
  true
end