JezK
Edit File: struct_layout.rb
# # Copyright (C) 2008-2010 Wayne Meissner # Copyright (C) 2008, 2009 Andrea Fazzi # Copyright (C) 2008, 2009 Luc Heinrich # # This file is part of ruby-ffi. # # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are met: # # * Redistributions of source code must retain the above copyright notice, this # list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above copyright notice # this list of conditions and the following disclaimer in the documentation # and/or other materials provided with the distribution. # * Neither the name of the Ruby FFI project nor the names of its contributors # may be used to endorse or promote products derived from this software # without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE # DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR # SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # module FFI class StructLayout # @return [Array<Array(Symbol, Numeric)> # Get an array of tuples (field name, offset of the field). def offsets members.map { |m| [ m, self[m].offset ] } end # @return [Numeric] # Get the offset of a field. def offset_of(field_name) self[field_name].offset end # An enum {Field} in a {StructLayout}. class Enum < Field # @param [AbstractMemory] ptr pointer on a {Struct} # @return [Object] # Get an object of type {#type} from memory pointed by +ptr+. def get(ptr) type.find(ptr.get_int(offset)) end # @param [AbstractMemory] ptr pointer on a {Struct} # @param value # @return [nil] # Set +value+ into memory pointed by +ptr+. def put(ptr, value) ptr.put_int(offset, type.find(value)) end end class InnerStruct < Field def get(ptr) type.struct_class.new(ptr.slice(self.offset, self.size)) end def put(ptr, value) raise TypeError, "wrong value type (expected #{type.struct_class})" unless value.is_a?(type.struct_class) ptr.slice(self.offset, self.size).__copy_from__(value.pointer, self.size) end end class Mapped < Field def initialize(name, offset, type, orig_field) super(name, offset, type) @orig_field = orig_field end def get(ptr) type.from_native(@orig_field.get(ptr), nil) end def put(ptr, value) @orig_field.put(ptr, type.to_native(value, nil)) end end end end