Class: FFI::Pointer

Inherits:
Object
  • Object
show all
Defined in:
lib/ffi/extra.rb

Direct Known Subclasses

ExecutableMemoryPointer

Instance Method Summary collapse

Instance Method Details

#read(type, *args) ⇒ Object Also known as: typecast 



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# File 'lib/ffi/extra.rb', line 81

def read (type, *args)
	if type.is_a?(Symbol)
		if respond_to? "read_#{type}"
			return send "read_#{type}"
		else
			type = FFI.find_type(type)
		end
	end

	if type.is_a?(Type::Builtin)
		send "read_#{type.name.downcase}", *args
	elsif type.is_a?(Class) && type.ancestors.member?(FFI::Struct) && !type.ancestors.member?(FFI::ManagedStruct)
		type.new(self, *args)
	elsif type.respond_to? :from_native
		type.from_native(typecast(type.native_type, *args), nil)
	else
		raise ArgumentError, 'you have to pass a Struct, a Builtin type or a Symbol'
	end
end

#read_array_of(type, number) ⇒ Object 



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# File 'lib/ffi/extra.rb', line 119

def read_array_of (type, number)
	if type.is_a?(Symbol)
		if respond_to? "read_array_of_#{type.downcase}"
			return send "read_array_of_#{type.downcase}", number
		else
			type = FFI.find_type(type)
		end
	end

	type = type.native_type if type.respond_to? :native_type

	if type.is_a?(Class) && type.ancestors.member?(FFI::Struct)
		read_array_of_pointer(number).map {|pointer|
			type.new(pointer)
		}
	else
		begin
			send "read_array_of_#{type.name.downcase}", number
		rescue NameError
			raise ArgumentError, "#{type.name} is not supported"
		end
	end
end

#write(what, type = nil) ⇒ Object 



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# File 'lib/ffi/extra.rb', line 103

def write (what, type = nil)
	if type
		if respond_to? "write_#{type.downcase}"
			send "write_#{type.downcase}", what
		else
			write_bytes what, what.size
		end
	else
		case what
			when FFI::Struct then write_bytes what.pointer.read_bytes(what.size)
			when String      then write_bytes what
			else raise ArgumentError, 'I do not know how to deal with this variable'
		end
	end
end

#write_array_of(type, data) ⇒ Object 



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# File 'lib/ffi/extra.rb', line 143

def write_array_of (type, data)
	if type.is_a?(Symbol)
		if respond_to? "write_array_of_#{type}"
			return send "write_array_of_#{type}", data
		else
			type = FFI.find_type(type)
		end
	end

	type = type.native_type if type.respond_to? :native_type

	if type.is_a?(Class) && type.ancestors.member?(FFI::Struct)
		write_array_of_pointer(data)
	else
		begin
			send "write_array_of_#{type.name.downcase}", data
		rescue NameError
			raise ArgumentError, "#{type.name} is not supported"
		end
	end
end