rt: Move generic implementation from sysdeps/pthread to rt

The pthread-based implementation is the generic one.  Replacing
the stubs makes it clear that they do not have to be adjusted for
the libpthread move.

Result of:

    git mv -f sysdeps/pthread/aio_misc.h sysdeps/generic/
    git mv sysdeps/pthread/timer_routines.c sysdeps/htl/
    git mv -f sysdeps/pthread/{aio,lio,timer}_*.c rt/

Followed by manual adjustment of the #include paths in
sysdeps/unix/sysv/linux/wordsize-64, and a move of the version
definitions formerly in sysdeps/pthread/Versions.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

1 files changed, 55 insertions, 9 deletions

diff --git a/rt/timer_gettime.c b/rt/timer_gettime.c
index 7bd94386a4..dd3b4a6281 100644
--- a/rt/timer_gettime.c
+++ b/rt/timer_gettime.c
@@ -1,10 +1,11 @@
-/* Copyright (C) 1999-2021 Free Software Foundation, Inc.
+/* Copyright (C) 2000-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
+   Contributed by Kaz Kylheku <kaz@ashi.footprints.net>.
 
    The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
+   modify it under the terms of the GNU Lesser General Public License as
+   published by the Free Software Foundation; either version 2.1 of the
+   License, or (at your option) any later version.
 
    The GNU C Library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -12,17 +13,62 @@
    Lesser General Public License for more details.
 
    You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <https://www.gnu.org/licenses/>.  */
+   License along with the GNU C Library; see the file COPYING.LIB.  If
+   not, see <https://www.gnu.org/licenses/>.  */
 
 #include <errno.h>
+#include <pthread.h>
 #include <time.h>
 
+#include "posix-timer.h"
+
+
 /* Get current value of timer TIMERID and store it in VLAUE.  */
 int
 timer_gettime (timer_t timerid, struct itimerspec *value)
 {
-  __set_errno (ENOSYS);
-  return -1;
+  struct timer_node *timer;
+  struct timespec now, expiry;
+  int retval = -1, armed = 0, valid;
+  clock_t clock = 0;
+
+  pthread_mutex_lock (&__timer_mutex);
+
+  timer = timer_id2ptr (timerid);
+  valid = timer_valid (timer);
+
+  if (valid) {
+    armed = timer->armed;
+    expiry = timer->expirytime;
+    clock = timer->clock;
+    value->it_interval = timer->value.it_interval;
+  }
+
+  pthread_mutex_unlock (&__timer_mutex);
+
+  if (valid)
+    {
+      if (armed)
+	{
+	  __clock_gettime (clock, &now);
+	  if (timespec_compare (&now, &expiry) < 0)
+	    timespec_sub (&value->it_value, &expiry, &now);
+	  else
+	    {
+	      value->it_value.tv_sec = 0;
+	      value->it_value.tv_nsec = 0;
+	    }
+	}
+      else
+	{
+	  value->it_value.tv_sec = 0;
+	  value->it_value.tv_nsec = 0;
+	}
+
+      retval = 0;
+    }
+  else
+    __set_errno (EINVAL);
+
+  return retval;
 }
-stub_warning (timer_gettime)