support: Add timespec.h

It adds useful functions for tests that use struct timespec.

Checked on x86_64-linux-gnu and i686-linux-gnu.

	* support/timespec.h: New file.  Provide timespec helper functions
	along with macros in the style of those in check.h.
	* support/timespec.c: New file.  Implement check functions declared
	in support/timespec.h.
	* support/timespec-add.c: New file from gnulib containing
	timespec_add implementation that handles overflow.
	* support/timespec-sub.c: New file from gnulib containing
	timespec_sub implementation that handles overflow.
	* support/README: Mention timespec.h.

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

1 files changed, 79 insertions, 0 deletions

diff --git a/support/timespec.h b/support/timespec.h
new file mode 100644
index 0000000..4a8b341
--- /dev/null
+++ b/support/timespec.h
@@ -0,0 +1,79 @@
+/* Useful functions for tests that use struct timespec.
+   Copyright (C) 2019 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   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.
+
+   The GNU C Library 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
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef SUPPORT_TIMESPEC_H
+#define SUPPORT_TIMESPEC_H
+
+#include <stdio.h>
+#include <time.h>
+#include <support/check.h>
+#include <support/xtime.h>
+
+struct timespec timespec_add (struct timespec, struct timespec)
+  __attribute__((const));
+struct timespec timespec_sub (struct timespec, struct timespec)
+  __attribute__((const));
+
+static inline struct timespec
+make_timespec (time_t s, long int ns)
+{
+  struct timespec r;
+  r.tv_sec = s;
+  r.tv_nsec = ns;
+  return r;
+}
+
+enum { TIMESPEC_HZ = 1000000000 };
+
+void test_timespec_before_impl (const char *file, int line,
+                                const struct timespec left,
+                                const struct timespec right);
+
+void test_timespec_equal_or_after_impl (const char *file, int line,
+                                        const struct timespec left,
+                                        const struct timespec right);
+
+/* Check that the timespec on the left represents a time before the
+   time on the right. */
+#define TEST_TIMESPEC_BEFORE(left, right)                               \
+  test_timespec_before_impl (__FILE__, __LINE__, (left), (right))
+
+#define TEST_TIMESPEC_BEFORE_NOW(left, clockid)                 \
+  ({                                                            \
+    struct timespec now;                                        \
+    const int saved_errno = errno;                              \
+    xclock_gettime ((clockid), &now);                           \
+    TEST_TIMESPEC_BEFORE ((left), now);                         \
+    errno = saved_errno;                                        \
+  })
+
+/* Check that the timespec on the left represents a after before the
+   time on the right. */
+#define TEST_TIMESPEC_EQUAL_OR_AFTER(left, right)                       \
+  test_timespec_equal_or_after_impl (__FILE__, __LINE__, left, right)
+
+#define TEST_TIMESPEC_NOW_OR_AFTER(clockid, right)              \
+  ({                                                            \
+    struct timespec now;                                        \
+    const int saved_errno = errno;                              \
+    xclock_gettime ((clockid), &now);                           \
+    TEST_TIMESPEC_EQUAL_OR_AFTER (now, (right));                \
+    errno = saved_errno;                                        \
+  })
+
+#endif /* SUPPORT_TIMESPEC_H */