(Interim checkin while we work on this)

* devices.cc: Regenerate.
* devices.h (device::noexpose): New field.
(device::dev_on_fs): Make a bit field.
(get_major): Use proper type for declaration.
(expose): New field.
(ext_dev_storage): Delete declaration.
(dev_storage_size): Ditto.
(dev_storage): New declaration.
(dev_storage_end): Ditto.
* devices.in: Mark /dev/ptym*, /dev/com*, /dev/pipe, /dev/fifo, and "/dev" as
"no expose".
* fhandler.h (fhandler_dev::lastrealpos): Delete declaration.
(fhandler_dev::devidx): Declare new field.
* fhandler_disk_file.cc: Move fhandler_dev functions into fhandler_dev.cc.
* fhandler_dev.cc: Add includes needed for functions moved from
fhandler_disk_file.cc.
(dev_storage_scan_start): Define place to start listing devices.
(dev_storage_size): Define size of array to scan.
(fhandler_dev::fhandler_dev): Move here from fhandler_disk_file.cc.
(fhandler_dev::opendir): Ditto.
(fhandler_dev::readdir): Just check devidx for non-NULL to determine when to go
to disk for /dev content.  Use dev_storage rather than ext_dev_storage.
Iterate over dev_storage using devidx pointer.  Use accessor functions rather
than raw references to the device struct.  Only increment dir->__d_position
when we are actually going to be returning something.  Add debug_printf for
exit.
(fhandler_dev::rewinddir): Set devidx as appropriate depending on whether
there's a /dev on disk or not.
* gendevices: Don't mark dev_storage static but do put it in the _RDATA
section.
* path.cc (path_conv::check): Use new "device::expose()" function to decide to
forbid programs from referencing internal device types.

winsup/cygwin/fhandler.h

@@ -1018,7 +1018,7 @@ class fhandler_disk_file: public fhandler_base
 
 class fhandler_dev: public fhandler_disk_file
 {
-  int lastrealpos;
+  const struct device *devidx;
   bool dir_exists;
 public:
   fhandler_dev ();