1 files changed, 88 insertions, 0 deletions
diff --git a/gnulib-tests/test-gettimeofday.c b/gnulib-tests/test-gettimeofday.c
new file mode 100644
index 0000000..d1d5206
--- /dev/null
+++ b/gnulib-tests/test-gettimeofday.c
@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2005, 2007, 2009-2023 Free Software Foundation, Inc.
+ *
+ * This program 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 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+/* Written by Jim Meyering and Bruno Haible.  */
+
+#include <config.h>
+
+#include <sys/time.h>
+
+#include "signature.h"
+SIGNATURE_CHECK (gettimeofday, int,
+                 (struct timeval *, GETTIMEOFDAY_TIMEZONE *));
+
+#include <time.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "macros.h"
+
+static void
+test_clobber ()
+{
+  time_t t = 0;
+  struct tm *lt;
+  struct tm saved_lt;
+  struct timeval tv;
+  lt = localtime (&t);
+  saved_lt = *lt;
+  gettimeofday (&tv, NULL);
+  if (memcmp (lt, &saved_lt, sizeof (struct tm)) != 0)
+    {
+      fprintf (stderr, "gettimeofday still clobbers the localtime buffer!\n");
+      exit (1);
+    }
+}
+
+static void
+test_consistency ()
+{
+  struct timeval tv1;
+  time_t tt2;
+  struct timeval tv3;
+  time_t tt4;
+
+  ASSERT (gettimeofday (&tv1, NULL) == 0);
+  tt2 = time (NULL);
+  ASSERT (gettimeofday (&tv3, NULL) == 0);
+  tt4 = time (NULL);
+
+  /* Verify monotonicity of gettimeofday().  */
+  ASSERT (tv1.tv_sec < tv3.tv_sec
+          || (tv1.tv_sec == tv3.tv_sec && tv1.tv_usec <= tv3.tv_usec));
+
+  /* Verify monotonicity of time().  */
+  ASSERT (tt2 <= tt4);
+
+  /* Verify that the tv_sec field of the result is the same as time(NULL).  */
+  /* Note: It's here that the dependency to the 'time' module is needed.
+     Without it, this assertion would sometimes fail on glibc systems, see
+     https://sourceware.org/bugzilla/show_bug.cgi?id=30200  */
+  ASSERT (tv1.tv_sec <= tt2);
+  ASSERT (tt2 <= tv3.tv_sec);
+  ASSERT (tv3.tv_sec <= tt4);
+}
+
+int
+main (void)
+{
+  test_clobber ();
+  test_consistency ();
+
+  return 0;
+}