ruby-x11/lib/X11/form.rb
2023-08-08 21:43:27 +01:00

457 lines
12 KiB
Ruby

require 'ostruct'
module X11
module Form
# A form object is an X11 packet definition. We use forms to encode
# and decode X11 packets as we send and receive them over a socket.
#
# We can create a packet definition as follows:
#
# class Point < BaseForm
# field :x, Int8
# field :y, Int8
# end
#
# p = Point.new(10,20)
# p.x => 10
# p.y => 20
# p.to_packet => "\n\x14"
#
# You can also read from a socket:
#
# Point.from_packet(socket) => #<Point @x=10 @y=20>
#
class BaseForm
include X11::Type
# initialize field accessors
def initialize(*params)
self.class.fields.each do |f|
if !f.value
param = params.shift
#p [f,param]
instance_variable_set("@#{f.name}", param)
end
end
end
def to_packet
# fetch class level instance variable holding defined fields
structs = self.class.instance_variable_get("@structs")
packet = structs.map do |s|
# fetch value of field set in initialization
value = s.type == :unused ? nil : instance_variable_get("@#{s.name}")
case s.type
when :field
if s.value
if s.value.respond_to?(:call)
value = s.value.call(self)
else
value = s.value
end
end
if value.is_a?(BaseForm)
value.to_packet
else
s.type_klass.pack(value)
end
when :unused
sz = s.size.respond_to?(:call) ? s.size.call(self) : s.size
"\x00" * sz
when :length
s.type_klass.pack(value.size)
when :string
s.type_klass.pack(value)
when :list
value.collect do |obj|
p obj
if obj.is_a?(BaseForm)
obj.to_packet
else
s.type_klass.pack(obj)
end
end
end
end.join
end
class << self
# FIXME: Doing small reads from socket is a bad idea, and
# the protocol provides length fields that makes it unnecessary.
def from_packet(socket)
# fetch class level instance variable holding defined fields
form = new
lengths = {}
@structs.each do |s|
case s.type
when :field
val = if s.type_klass.superclass == BaseForm
s.type_klass.from_packet(socket)
else
s.type_klass.unpack( socket.read(s.type_klass.size) )
end
form.instance_variable_set("@#{s.name}", val)
when :unused
sz = s.size.respond_to?(:call) ? s.size.call(self) : s.size
socket.read(sz)
when :length
size = s.type_klass.unpack( socket.read(s.type_klass.size) )
lengths[s.name] = size
when :string
val = s.type_klass.unpack(socket, lengths[s.name])
form.instance_variable_set("@#{s.name}", val)
when :list
val = lengths[s.name].times.collect do
s.type_klass.from_packet(socket)
end
form.instance_variable_set("@#{s.name}", val)
end
end
return form
end
def field(name, type_klass, type = nil, value: nil)
# name, type_klass, type = args
class_eval { attr_accessor name }
s = OpenStruct.new
s.name = name
s.type = (type == nil ? :field : type)
s.type_klass = type_klass
s.value = value
@structs ||= []
@structs << s
end
def unused(size)
s = OpenStruct.new
s.size = size
s.type = :unused
@structs ||= []
@structs << s
end
def fields
@structs.dup.delete_if{|s| s.type == :unused or s.type == :length}
end
end
end
##
## X11 Packet Defintions
##
class ClientHandshake < BaseForm
field :byte_order, Uint8
unused 1
field :protocol_major_version, Uint16
field :protocol_minor_version, Uint16
field :auth_proto_name, Uint16, :length
field :auth_proto_data, Uint16, :length
unused 2
field :auth_proto_name, String8, :string
field :auth_proto_data, String8, :string
end
class FormatInfo < BaseForm
field :depth, Uint8
field :bits_per_pixel, Uint8
field :scanline_pad, Uint8
unused 5
end
class VisualInfo < BaseForm
field :visual_id, VisualID
field :qlass, Uint8
field :bits_per_rgb_value, Uint8
field :colormap_entries, Uint16
field :red_mask, Uint32
field :green_mask, Uint32
field :blue_mask, Uint32
unused 4
end
class DepthInfo < BaseForm
field :depth, Uint8
unused 1
field :visuals, Uint16, :length
unused 4
field :visuals, VisualInfo, :list
end
class ScreenInfo < BaseForm
field :root, Window
field :default_colormap, Colormap
field :white_pixel, Colornum
field :black_pixel, Colornum
field :current_input_masks, Mask
field :width_in_pixels, Uint16
field :height_in_pixels, Uint16
field :width_in_millimeters, Uint16
field :height_in_millimeters, Uint16
field :min_installed_maps, Uint16
field :max_installed_maps, Uint16
field :root_visual, VisualID
field :backing_stores, Uint8
field :save_unders, Bool
field :root_depth, Uint8
field :depths, Uint8,:length
field :depths, DepthInfo, :list
end
class DisplayInfo < BaseForm
field :release_number, Uint32
field :resource_id_base, Uint32
field :resource_id_mask, Uint32
field :motion_buffer_size, Uint32
field :vendor, Uint16, :length
field :maximum_request_length, Uint16
field :screens, Uint8, :length
field :formats, Uint8, :length
field :image_byte_order, Signifigance
field :bitmap_bit_order, Signifigance
field :bitmap_format_scanline_unit, Uint8
field :bitmap_format_scanline_pad, Uint8
field :min_keycode, KeyCode
field :max_keycode, KeyCode
unused 4
field :vendor, String8, :string
field :formats, FormatInfo, :list
field :screens, ScreenInfo, :list
end
class Rectangle < BaseForm
field :x, Int16
field :y, Int16
field :width, Uint16
field :height, Uint16
end
class Error < BaseForm
field :error, Uint8
field :code, Uint8
field :sequence_number, Uint16
field :bad_resource_id, Uint32
field :minor_opcode, Uint16
field :major_opcode, Uint8
unused 21
end
# Requests
CopyFromParent = 0
InputOutput = 1
InputOnly = 2
CWBackPixel = 0x0002
CWEventMask = 0x0800
KeyPressMask = 0x00001
ButtonPressMask = 0x00004
ExposureMask = 0x08000
StructureNotifyMask = 0x20000
SubstructureNotifyMask = 0x80000
class CreateWindow < BaseForm
field :opcode, Uint8, value: 1
field :depth, Uint8
field :request_length, Uint16, value: ->(cw) { len = 8 + cw.value_list.length; p len; len }
field :wid, Window
field :parent, Window
field :x, Int16
field :y, Int16
field :width, Uint16
field :height, Uint16
field :border_width, Uint16
field :window_class, Uint16
field :visual, VisualID
field :value_mask, Bitmask
field :value_list, Uint32, :list
end
class MapWindow < BaseForm
field :opcode, Uint8, value: 8
unused 1
field :request_length, Uint16, value: 2
field :window, Window
end
class OpenFont < BaseForm
field :opcode, Uint8, value: 45
unused 1
field :request_length, Uint16, value: ->(of) {
3+(of.name.length+3)/4
}
field :fid, Font
field :name, Uint16, :length
unused 2
field :name, String8, :string
end
class ListFonts < BaseForm
field :opcode, Uint8, value: 49
unused 1
field :request_length, Uint16, value: ->(lf) {
2+(lf.pattern.length+4)/4
}
field :max_names, Uint16
field :length_of_pattern, Uint16,value: ->(lf) {
lf.pattern.length
}
field :pattern, String8
end
class Str < BaseForm
field :name, Uint8, :length, value: ->(str) { str.name.length }
field :name, String8Unpadded, :string
def to_s
name
end
end
class ListFontsReply < BaseForm
field :reply, Uint8, value: 1
unused 1
field :sequence_number, Uint16
field :reply_length, Uint32
field :names, Uint16, :length
unused 22
field :names, Str, :list
end
FunctionMask = 0x1
PlaneMask = 0x2
ForegroundMask = 0x04
BackgroundMask = 0x08
FontMask = 0x4000
class CreateGC < BaseForm
field :opcode, Uint8, value: 55
unused 1
field :request_length, Uint16, value: ->(cw) {
len = 4 + cw.value_list.length
}
field :cid, Gcontext
field :drawable, Drawable
field :value_mask, Bitmask
field :value_list, Uint32, :list
end
class ChangeGC < BaseForm
field :opcode, Uint8, value: 56
unused 1
field :request_length, Uint16, value: ->(ch) {
3+ ch.value_list.length
}
field :gc, Gcontext
field :value_mask, Bitmask
field :value_list, Uint32, :list
end
class ClearArea < BaseForm
field :opcode, Uint8, value: 61
field :exposures, Bool
field :request_length, Uint16, value: 4
field :window, Window
field :x, Int16
field :y, Int16
field :width, Uint16
field :height, Uint16
end
class PolyFillRectangle < BaseForm
field :opcode, Uint8, value: 70
unused 1
field :request_length, Uint16, value: ->(ob) {
len = 3 + 2*(Array(ob.rectangles).length)
}
field :drawable, Drawable
field :gc, Uint32
field :rectangles, Rectangle, :list
end
Bitmap = 0
XYPixmap=1
ZPixmap=2
class PutImage < BaseForm
field :opcode, Uint8, value: 72
field :format, Uint8
field :request_length, Uint16, value: ->(pi) {
6+(pi.data.length+3)/4
}
field :drawable, Drawable
field :gc, Gcontext
field :width, Uint16
field :height, Uint16
field :dstx, Int16
field :dsty, Int16
field :left_pad, Uint8
field :depth, Uint8
unused 2
field :data, String8 #, :string
end
class ImageText8 < BaseForm
field :opcode, Uint8, value: 76
field :n, Uint8, :length
field :request_length, Uint16, value: ->(it) { 4+(it.n.length+4)/4 }
field :drawable, Drawable
field :gc, Gcontext
field :x, Int16
field :y, Int16
field :n, String8, :string
end
# Events (page ~157)
# FIXME: Events have quite a bit of redundancy, but unfortunately
# BaseForm can't handle subclassing well.
class Expose < BaseForm
field :code, Uint8
unused 1
field :sequence_number, Uint16
field :widow, Window
field :x, Uint16
field :y, Uint16
field :width, Uint16
field :height, Uint16
field :count, Uint16
unused 14
end
class MapNotify < BaseForm
field :code, Uint8
unused 1
field :sequence_number, Uint16
field :event, Window
field :override_redirect, Bool
unused 19
end
class ConfigureNotify < BaseForm
field :code, Uint8
unused 1
field :sequence_number, Uint16
field :event, Window
field :above_sibling, Window
field :x, Int16
field :y, Int16
field :width, Uint16
field :height, Uint16
field :border_width, Uint16
field :override_redirect, Bool
unused 5
end
end
end