I have the following code which is fine if I give invalid parameters (though, obviously doesn't work), but whenever I give accurate parameters, ruby segfaults. I'm inclined to believe that this is a problem with my code and/or the ability of ruby to actually call this API function, but I'd like some more input. I've tried with both Win32API and DL::Importer with the same results. Is there any way to get this to work?
For the curious, there's full background available here, including attempts with Win32API and DL::Importer on different branches. You are looking for examples/windows-test in both cases.
EDIT: I've managed to get RegisterClassEx to work, but this still isn't helping. Ruby is silently crashing in CreateWindowEx.
The following gives output like this:
wndproc: 4293787656
hInstance: 4194304
Entering RegisterClassEx
Window Class: 49795
Entering CreateWindowEx
EDIT 2: My code in progress has grown a little large to be pasting it all into SE. If you want all the background, you can see it at the link above. I've tried to keep everything relevant included here though.
class Windows
def initialize
puts "wndproc: #{Win32::User32::WNDPROC}"
hInstance = Win32::Kernel32::GetModuleHandle(DL::NULL)
puts "hInstance: #{hInstance}"
puts "Entering RegisterClassEx"
@window_class_struct = Win32::User32::WNDCLASSEX.malloc
@window_class_struct.cbSize = Win32::User32::WNDCLASSEX.size
@window_class_struct.style = Win32::User32::CS_HREDRAW | Win32::User32::CS_VREDRAW
@window_class_struct.lpfnWndProc = Win32::User32::WNDPROC
@window_class_struct.cbClsExtra = 0
@window_class_struct.cbWndExtra = 0
@window_class_struct.hInstance = hInstance
@window_class_struct.hIcon = 0
@window_class_struct.hCursor = 0
@window_class_struct.hbrBackground = Win32::User32::COLOR_WINDOWFRAME
@window_class_struct.lpszMenuName = DL::NULL
@window_class_struct.lpszClassName = 'ruby-skype'
@window_class_struct.hIconSm = 0
p @window_class_struct
@window_class = Win32::User32::RegisterClassEx(@window_class_struct.to_i)
puts "Window Class: #{@window_class}"
puts "Entering CreateWindowEx"
@window = Win32::User32::CreateWindowEx(0, 'ruby-skype', 'ruby-skype', Win32::User32::WS_OVERLAPPEDWINDOW,
0, 0, 200, 200, DL::NULL, DL::NULL, DL::NULL)
puts "Exited CreateWindowEx"
p @window
end
module Win32
module Types
def included(m)
m.module_eval {
include ::DL::Win32Types
# @see http://msdn.microsoft.com/en-us/library/windows/desktop/aa383751.aspx
typealias('HBRUSH', 'HANDLE')
typealias('HCURSOR', 'HANDLE')
typealias('HICON', 'HANDLE')
typealias('HMENU', 'HANDLE')
typealias('HMODULE', 'HANDLE')
typealias('LPCTSTR', 'unsigned char *')
typealias('LPVOID', 'void *')
typealias('WNDPROC', 'void *') # Actually a function pointer
typealias('WNDCLASSEX', 'void *') # struct
}
end
module_function :included
end
module User32
extend DL
extend DL::Importer
dlload 'user32'
include Types
extern 'HWND CreateWindowEx(DWORD, LPCTSTR, LPCTSTR, DWORD, int, int, int, int, HWND, HMENU, HINSTANCE)'
WNDPROC = set_callback DL::TYPE_LONG, 4 do |window_handle, message_id, wParam, lParam|
puts "WM: #{message_id}"
end
end
end
end
Windows.new
Solution: Use ffi. For whatever reason, it just doesn't work in DL (Win32API uses DL under the hood)
Full credit goes here, wherever this is (I can't read Japanese): http://www19.atwiki.jp/tmtbnc/m/pages/56.html
My guess is it's because DL doesn't seem to support stdcall, but I honestly don't know enough about it to know.
The FFI solution as used by me is below:
class Windows
def initialize
hInstance = Win32::GetModuleHandle(nil)
@window_class = Win32::WNDCLASSEX.new
@window_class[:style] = Win32::CS_HREDRAW | Win32::CS_VREDRAW
@window_class[:lpfnWndProc] = method(:message_pump)
@window_class[:hInstance] = hInstance
@window_class[:hbrBackground] = Win32::COLOR_WINDOWFRAME
@window_class[:lpszClassName] = FFI::MemoryPointer.from_string 'ruby-skype'
@window = Win32::CreateWindowEx(Win32::WS_EX_LEFT, ::FFI::Pointer.new(@window_class.atom), 'ruby-skype', Win32::WS_OVERLAPPEDWINDOW,
0, 0, 0, 0, Win32::NULL, Win32::NULL, hInstance, nil)
end
def message_pump(window_handle, message_id, wParam, lParam)
puts "WM: #{message_id}"
Win32::DefWindowProc(window_handle, message_id, wParam, lParam)
end
module Win32
extend FFI::Library
ffi_lib('user32', 'kernel32')
ffi_convention(:stdcall)
private
def self._func(*args)
attach_function *args
case args.size
when 3
module_function args[0]
when 4
module_function args[0]
alias_method(args[1], args[0])
module_function args[1]
end
end
public
ULONG_PTR = FFI::TypeDefs[:ulong]
LONG_PTR = FFI::TypeDefs[:long]
ULONG = FFI::TypeDefs[:ulong]
LONG = FFI::TypeDefs[:long]
LPVOID = FFI::TypeDefs[:pointer]
INT = FFI::TypeDefs[:int]
BYTE = FFI::TypeDefs[:uint16]
DWORD = FFI::TypeDefs[:ulong]
BOOL = FFI::TypeDefs[:int]
UINT = FFI::TypeDefs[:uint]
POINTER = FFI::TypeDefs[:pointer]
VOID = FFI::TypeDefs[:void]
HWND = HICON = HCURSOR = HBRUSH = HINSTANCE = HGDIOBJ =
HMENU = HMODULE = HANDLE = ULONG_PTR
LPARAM = LONG_PTR
WPARAM = ULONG_PTR
LPCTSTR = LPMSG = LPVOID
LRESULT = LONG_PTR
ATOM = BYTE
NULL = 0
WNDPROC = callback(:WindowProc, [HWND, UINT, WPARAM, LPARAM], LRESULT)
class WNDCLASSEX < FFI::Struct
layout :cbSize, UINT,
:style, UINT,
:lpfnWndProc, WNDPROC,
:cbClsExtra, INT,
:cbWndExtra, INT,
:hInstance, HANDLE,
:hIcon, HICON,
:hCursor, HCURSOR,
:hbrBackground, HBRUSH,
:lpszMenuName, LPCTSTR,
:lpszClassName, LPCTSTR,
:hIconSm, HICON
def initialize(*args)
super
self[:cbSize] = self.size
@atom = 0
end
def register_class_ex
(@atom = Win32::RegisterClassEx(self)) != 0 ? @atom : raise("RegisterClassEx Error")
end
def atom
@atom != 0 ? @atom : register_class_ex
end
end # WNDCLASSEX
class POINT < FFI::Struct
layout :x, LONG,
:y, LONG
end
class MSG < FFI::Struct
layout :hwnd, HWND,
:message, UINT,
:wParam, WPARAM,
:lParam, LPARAM,
:time, DWORD,
:pt, POINT
end
_func(:RegisterWindowMessage, :RegisterWindowMessageA, [LPCTSTR], UINT)
_func(:GetModuleHandle, :GetModuleHandleA, [LPCTSTR], HMODULE)
_func(:RegisterClassEx, :RegisterClassExA, [LPVOID], ATOM)
_func(:CreateWindowEx, :CreateWindowExA, [DWORD, LPCTSTR, LPCTSTR, DWORD, INT, INT, INT, INT, HWND, HMENU, HINSTANCE, LPVOID], HWND)
_func(:GetMessage, :GetMessageA, [LPMSG, HWND, UINT, UINT], BOOL)
_func(:TranslateMessage, [LPVOID], BOOL)
_func(:DispatchMessage, :DispatchMessageA, [LPVOID], BOOL)
_func(:DefWindowProc, :DefWindowProcA, [HWND, UINT, WPARAM, LPARAM], LRESULT)
# @!group Predefined WindowHandle's
#
# These are WindowHandle's provided by the Win32 API for special purposes.
# Target for SendMessage(). Broadcast to all windows.
HWND_BROADCAST = 0xffff
# Used as a parent in CreateWindow(). Signifies that this should be a message-only window.
HWND_MESSAGE = -3
# @!endgroup
# CreateWindow Use Default Value
CW_USEDEFAULT = 0x80000000
COLOR_WINDOW = 5
COLOR_WINDOWFRAME = 6
# @!group Class Style contants.
CS_VREDRAW = 0x0001
CS_HREDRAW = 0x0002
# @!group Window Style constants
#
# This is only a subset.
# @see http://msdn.microsoft.com/en-us/library/windows/desktop/ms632600.aspx
WS_BORDER = 0x00800000
WS_CAPTION = 0x00C00000
WS_DISABLED = 0x08000000
WS_OVERLAPPED = 0x00000000
WS_POPUP = 0x80000000
WS_SIZEBOX = 0x00040000
WS_SYSMENU = 0x00080000
WS_THICKFRAME = 0x00040000
WS_MAXIMIZEBOX = 0x00010000
WS_MINIMIZEBOX = 0x00020000
WS_OVERLAPPEDWINDOW = WS_OVERLAPPED | WS_CAPTION | WS_SYSMENU | WS_THICKFRAME | WS_MINIMIZEBOX | WS_MAXIMIZEBOX
WS_POPUPWINDOW = WS_POPUP | WS_BORDER | WS_SYSMENU
# @!group Window Extended Style constants
#
# This is only a subset.
# @see http://msdn.microsoft.com/en-us/library/windows/desktop/ff700543.aspx
WS_EX_LEFT = 0
# @!endgroup
end
end