PR modula2/110779 SysClock can not read the clock

This patch completes the implementation of the ISO module
SysClock.mod.  Three new testcases are provided.  wrapclock.{cc,def}
are new support files providing access to clock_settime, clock_gettime
and glibc timezone variables.

gcc/m2/ChangeLog:

	PR modula2/110779
	* gm2-libs-iso/SysClock.mod: Re-implement using wrapclock.
	* gm2-libs-iso/wrapclock.def: New file.

libgm2/ChangeLog:

	PR modula2/110779
	* config.h.in: Regenerate.
	* configure: Regenerate.
	* configure.ac (GM2_CHECK_LIB): Check for clock_gettime
	and clock_settime.
	* libm2iso/Makefile.am (M2DEFS): Add wrapclock.def.
	* libm2iso/Makefile.in: Regenerate.
	* libm2iso/wraptime.cc: Replace HAVE_TIMEVAL with
	HAVE_STRUCT_TIMEVAL.
	* libm2iso/wrapclock.cc: New file.

gcc/testsuite/ChangeLog:

	PR modula2/110779
	* gm2/iso/run/pass/m2date.mod: New test.
	* gm2/iso/run/pass/testclock.mod: New test.
	* gm2/iso/run/pass/testclock2.mod: New test.

Signed-off-by: Gaius Mulley <gaiusmod2@gmail.com>

1 files changed, 220 insertions, 0 deletions

diff --git a/libgm2/libm2iso/wrapclock.cc b/libgm2/libm2iso/wrapclock.cc
new file mode 100644
index 0000000..7ee1f25
--- /dev/null
+++ b/libgm2/libm2iso/wrapclock.cc
@@ -0,0 +1,220 @@
+/* wrapclock.cc provides access to time related system calls.
+
+Copyright (C) 2009-2022 Free Software Foundation, Inc.
+Contributed by Gaius Mulley <gaius.mulley@southwales.ac.uk>.
+
+This file is part of GNU Modula-2.
+
+GNU Modula-2 is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 3, or (at your option)
+any later version.
+
+GNU Modula-2 is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+<http://www.gnu.org/licenses/>.  */
+
+#include "config.h"
+#include <m2rts.h>
+
+#define EXPORT(FUNC) m2iso ## _wrapclock_ ## FUNC
+#define M2EXPORT(FUNC) m2iso ## _M2_wrapclock_ ## FUNC
+#define M2LIBNAME "m2iso"
+
+#if defined(HAVE_STDLIB_H)
+#include "stdlib.h"
+#endif
+
+#if defined(HAVE_UNISTD_H)
+#include "unistd.h"
+#endif
+
+#if defined(HAVE_SYS_TYPES_H)
+#include "sys/types.h"
+#endif
+
+#if defined(HAVE_SYS_TIME_H)
+#include "sys/time.h"
+#endif
+
+#if defined(HAVE_TIME_H)
+#include "time.h"
+#endif
+
+#if defined(HAVE_MALLOC_H)
+#include "malloc.h"
+#endif
+
+#if defined(HAVE_LIMITS_H)
+#include "limits.h"
+#endif
+
+#if !defined(NULL)
+#define NULL (void *)0
+#endif
+
+
+extern "C" long int
+EXPORT(timezone) (void)
+{
+  struct tm result;
+  struct timespec ts;
+
+  if (clock_gettime (CLOCK_REALTIME, &ts) == 0)
+    {
+      time_t time = ts.tv_sec;
+      localtime_r (&time, &result);
+      return result.tm_gmtoff;
+    }
+  else
+    return timezone;
+}
+
+
+extern "C" int
+EXPORT(daylight) (void)
+{
+  return daylight;
+}
+
+
+/* isdst returns 1 if daylight saving time is currently in effect and
+   returns 0 if it is not.  */
+
+extern "C" int
+EXPORT(isdst) (void)
+{
+  struct tm result;
+  struct timespec ts;
+
+  if (clock_gettime (CLOCK_REALTIME, &ts) == 0)
+    {
+      time_t time = ts.tv_sec;
+      localtime_r (&time, &result);
+      return result.tm_isdst;
+    }
+  else
+    return 0;
+}
+
+
+/* tzname returns the string associated with the local timezone.
+   The daylight value is 0 or 1.  The value 0 returns the non
+   daylight saving timezone string and the value of 1 returns the
+   daylight saving timezone string.  */
+
+extern "C" char *
+EXPORT(tzname) (int daylight)
+{
+  return tzname[daylight];
+}
+
+
+/* GetTimeRealtime performs return gettime (CLOCK_REALTIME, ts).
+   gettime returns 0 on success and -1 on failure.  If the underlying
+   system does not have gettime then GetTimeRealtime returns 1.  */
+
+extern "C" int
+EXPORT(GetTimeRealtime) (struct timespec *ts)
+{
+#if defined(HAVE_CLOCK_GETTIME)
+  return clock_gettime (CLOCK_REALTIME, ts);
+#else
+  return 1;
+#endif
+}
+
+
+/* SetTimeRealtime performs return settime (CLOCK_REALTIME, ts).
+   gettime returns 0 on success and -1 on failure.  If the underlying
+   system does not have gettime then GetTimeRealtime returns 1.  */
+
+extern "C" int
+EXPORT(SetTimeRealtime) (struct timespec *ts)
+{
+#if defined(HAVE_CLOCK_GETTIME)
+  return clock_settime (CLOCK_REALTIME, ts);
+#else
+  return 1;
+#endif
+}
+
+
+/* InitTimespec returns a newly created opaque type.  */
+
+extern "C" struct timespec *
+EXPORT(InitTimespec) (void)
+{
+  return (struct timespec *)malloc (sizeof (struct timespec));
+}
+
+
+/* KillTimeval deallocates the memory associated with an opaque type.  */
+
+extern "C" struct timespec *
+EXPORT(KillTimespec) (void *ts)
+{
+#if defined(HAVE_MALLOC_H)
+  free (ts);
+#endif
+  return NULL;
+}
+
+
+/* GetTimespec retrieves the number of seconds and nanoseconds from the
+   timespec.  */
+
+extern "C" void
+EXPORT(GetTimespec) (timespec *ts, unsigned long *sec, unsigned long *nano)
+{
+  *sec = ts->tv_sec;
+  *nano = ts->tv_nsec;
+}
+
+
+/* SetTimespec sets the number of seconds and nanoseconds into timespec.  */
+
+extern "C" void
+EXPORT(SetTimespec) (timespec *ts, unsigned long sec, unsigned long nano)
+{
+  ts->tv_sec = sec;
+  ts->tv_nsec = nano;
+}
+
+
+/* init - init/finish functions for the module */
+
+/* GNU Modula-2 linking hooks.  */
+
+extern "C" void
+M2EXPORT(init) (int, char **, char **)
+{
+}
+
+extern "C" void
+M2EXPORT(fini) (int, char **, char **)
+{
+}
+
+extern "C" void
+M2EXPORT(dep) (void)
+{
+}
+
+extern "C" void __attribute__((__constructor__))
+M2EXPORT(ctor) (void)
+{
+  m2iso_M2RTS_RegisterModule ("wrapclock", M2LIBNAME,
+			      M2EXPORT(init), M2EXPORT(fini),
+			      M2EXPORT(dep));
+}