Implement watches for GIOChannels for write file descriptors on Win32

Implement watches for GIOChannels for write file descriptors on Win32

2006-03-02  Marcus Brinkmann  <mb@g10code.de>

	Implement watches for GIOChannels for write file descriptors on
	Win32 (#333098).

	* glib/giowin32.c (GIOWin32Channel): Add a new direction field.
	(read_thread): Initialize direction.
	(write_thread): New function.
	(buffer_write): New function.
	(g_io_win32_prepare): Handle the G_IO_WIN32_FILE_DESC case for the
	write direction.
	(g_io_win32_fd_write): Call buffer_write() if there is a writer
	thread.
	(g_io_win32_fd_close): Set space_avail_event for writer threads.
	(g_io_win32_fd_create_watch): Create the writer thread if
	condition is G_IO_OUT.
	(g_io_channel_win32_make_pollfd): Likewise here.