Introduce device class to cygwin throughout. Rename FH_DISK to FH_FS

throughout.
* dcrt0.cc (dll_crt0_1): Initialize device globals via device::init.
* dtable.cc (dtable::init_std_file_from_handle): Use device numbers rather than
names when they are known.  Should speed up process startup slightly.
(dtable::build_fhandler_from_name): Pass path_conv device to build_fhandler.
(dtable::build_fhandler): Accept device argument rather than separate
device/unit arguments.
(dtable::build_fhandler): Ditto.  Separate switch statement by devices which
take units and those which don't.  Build unix/win32 names from device if
required.
(dtable::dup_worker): Reflect changes to build_fhandler arguments.
* dtable.h (dtable::build_fhandler): Ditto.
* fhandler.cc (fhandler_base::set_name): Eliminate unit argument.  Use get_unit
to derive unit.
* fhandler.h: Separate FH device defines into devices.h include.  Define
is_slow as appropriate for each fhandler_class.
(fhandler_base::dev): New element.
(fhandler_base::fhandler_base): Eliminate unit argument.
(fhandler_base::get_device): Return device number.
(fhandler_base::get_major): Return device major number.
(fhandler_base::get_minor): Return device minor number.
(fhandler_base::get_unit): Ditto.
(fhandler_base::get_native_name): Return device format field.
(fhandler_fifo): New class.
(select_stuff::device_specific): Remove array.
(select_stuff::device_specific_pipe): New class element.
(select_stuff::device_specific_socket): New class element.
(select_stuff::device_specific_serial): New class element.
(select_stuff::select_stuff): Initialize new elements.
* fhandler_disk_file.cc (fhandler_cygdrive::fhandler_cygdrive): Remove unit
initialization.
* fhandler_tty.cc (fhandler_tty_master::init_console): Use "console_dev" global
to initialize captive console used by tty master.
* mmap.cc (mmap_record::devtype_): Remove.
(mmap_record::dev): New.
(mmap_record::mmap_record): Use dev.
(mmap_record::get_device): Implement via dev.
* net.cc (fdsock): Use socket_dev global to initialize socket fhandler.
* path.cc (path_conv::check): Accommodate new path_conv::dev element.
(get_devn): Eliminate.
(get_raw_device_number): Ditto.
(get_device_number): Ditto.
(win32_device_name): Accept dev argument.  Use it.  Use device::parse to derive
potential device name.
(mount_info::conv_to_win32_path): Accept dev argument.  Use it.
* path.h (path_conv::devn): Eliminate.
(path_conv::unit): Ditto.
(path_conv::dev): Declare.
(path_conv::path_conv): Don't initialize deleted members.
(path_conv::is_device): Implement via dev element.
(path_conv::get_devn): Ditto.
(path_conv::get_unitn): Ditto.
* pipe.cc (make_pipe): Use pipe[rw]_dev in fhandler construction.
* select.cc: Use new device_specific_* select class elements
* shared_info.h (CURR_MOUNT_MAGIC): Update.
(mount_info::conv_to_win32_path): Reflect new arguments.
* syscalls.cc (fstat64): Just use get_device() without interpretation for
st_dev element.
(stat_worker): Ditto.
* tty.cc (create_tty_master): Use ttym_dev in fhandler constructor.
(tty::common_init): Check for tty major device number rather than FH_TTYM.

winsup/cygwin/dcrt0.cc

@@ -551,6 +551,7 @@ dll_crt0_1 ()
 
   /* Set the os_being_run global. */
   wincap.init ();
+  device::init ();
   check_sanity_and_sync (user_data);
 
   do_global_ctors (&__CTOR_LIST__, 1);