module DL::CStructBuilder

Used to construct C classes (CUnion, CStruct, etc)

DL::Importer#struct and DL::Importer#union wrap this functionality in an easy-to-use manner.

Public Class Methods

create(klass, types, members) click to toggle source

Construct a new class given a C:

  • class klass (CUnion, CStruct, or other that provide an entity_class)

  • types (DL:TYPE_INT, DL::TYPE_SIZE_T, etc., see the C types constants)

  • corresponding members

DL::Importer#struct and DL::Importer#union wrap this functionality in an easy-to-use manner.

Example:

require 'dl/struct'
require 'dl/cparser'
include DL::CParser
types, members = parse_struct_signature(['int i','char c'])
MyStruct = DL::CStructBuilder.create(CUnion, types, members)
obj = MyStruct.allocate

# File ext/dl/lib/dl/struct.rb, line 50
 def create(klass, types, members)
 new_class = Class.new(klass){
 define_method(:initialize){|addr|
 @entity = klass.entity_class.new(addr, types)
 @entity.assign_names(members)
 }
 define_method(:to_ptr){ @entity }
 define_method(:to_i){ @entity.to_i }
 members.each{|name|
 define_method(name){ @entity[name] }
 define_method(name + "="){|val| @entity[name] = val }
 }
 }
 size = klass.entity_class.size(types)
 new_class.module_eval(" def new_class.size()
 #{size}
 end
 def new_class.malloc()
 addr = DL.malloc(#{size})
 new(addr)
 end
", __FILE__, __LINE__+1)
 return new_class
 end

Private Instance Methods

create(klass, types, members) click to toggle source

Construct a new class given a C:

  • class klass (CUnion, CStruct, or other that provide an entity_class)

  • types (DL:TYPE_INT, DL::TYPE_SIZE_T, etc., see the C types constants)

  • corresponding members

DL::Importer#struct and DL::Importer#union wrap this functionality in an easy-to-use manner.

Example:

require 'dl/struct'
require 'dl/cparser'
include DL::CParser
types, members = parse_struct_signature(['int i','char c'])
MyStruct = DL::CStructBuilder.create(CUnion, types, members)
obj = MyStruct.allocate

# File ext/dl/lib/dl/struct.rb, line 50
 def create(klass, types, members)
 new_class = Class.new(klass){
 define_method(:initialize){|addr|
 @entity = klass.entity_class.new(addr, types)
 @entity.assign_names(members)
 }
 define_method(:to_ptr){ @entity }
 define_method(:to_i){ @entity.to_i }
 members.each{|name|
 define_method(name){ @entity[name] }
 define_method(name + "="){|val| @entity[name] = val }
 }
 }
 size = klass.entity_class.size(types)
 new_class.module_eval(" def new_class.size()
 #{size}
 end
 def new_class.malloc()
 addr = DL.malloc(#{size})
 new(addr)
 end
", __FILE__, __LINE__+1)
 return new_class
 end