Cygwin: implement extensible clock interface

- Drop hires_[nm]s clocks, rename hires.h to clock.h.

- Implement clk_t class as an extensible clock class in new file clock.cc.

- Introduce get_clock(clock_id) returning a pointer to the clk_t instance
  for clock_id.  Provide the following methods along the lines of the former
  hires classes:

	void		clk_t::nsecs (struct timespec *);
	ULONGLONG	clk_t::nsecs ();
	LONGLONG	clk_t::usecs ();
	LONGLONG	clk_t::msecs ();
	void 		clk_t::resolution (struct timespec *);

- Add CLOCK_REALTIME_COARSE, CLOCK_MONOTONIC_RAW, CLOCK_MONOTONIC_COARSE
  and CLOCK_BOOTTIME clocks.

- Allow clock_nanosleep, pthread_condattr_setclock and timer_create to use
  all new clocks (both clocks should be usable with a small tweak, though).

- Bump DLL major version to 2.12.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

winsup/cygwin/fhandler_socket_unix.cc

@@ -24,7 +24,6 @@
 #include "fhandler.h"
 #include "dtable.h"
 #include "cygheap.h"
-#include "hires.h"
 #include "shared_info.h"
 #include "ntdll.h"
 #include "miscfuncs.h"
@@ -1269,7 +1268,7 @@ fhandler_socket_unix::wait_pipe_thread (PUNICODE_STRING pipe_name)
   pwbuf->NameLength = pipe_name->Length;
   pwbuf->TimeoutSpecified = TRUE;
   memcpy (pwbuf->Name, pipe_name->Buffer, pipe_name->Length);
-  stamp = ntod.nsecs ();
+  stamp = get_clock (CLOCK_MONOTONIC)->n100secs ();
   do
     {
       status = NtFsControlFile (npfsh, evt, NULL, NULL, &io, FSCTL_PIPE_WAIT,
@@ -1298,7 +1297,8 @@ fhandler_socket_unix::wait_pipe_thread (PUNICODE_STRING pipe_name)
 		  /* Another concurrent connect grabbed the pipe instance
 		     under our nose.  Fix the timeout value and go waiting
 		     again, unless the timeout has passed. */
-		  pwbuf->Timeout.QuadPart -= (stamp - ntod.nsecs ()) / 100LL;
+		  pwbuf->Timeout.QuadPart -=
+		    stamp - get_clock (CLOCK_MONOTONIC)->n100secs ();
 		  if (pwbuf->Timeout.QuadPart >= 0)
 		    {
 		      status = STATUS_IO_TIMEOUT;