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diff --git a/src/c-ares/ares__timeval.c b/src/c-ares/ares__timeval.c
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+
+/* Copyright (C) 2008 by Daniel Stenberg et al
+ *
+ * Permission to use, copy, modify, and distribute this software and its
+ * documentation for any purpose and without fee is hereby granted, provided
+ * that the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation, and that the name of M.I.T. not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission. M.I.T. makes no representations about the
+ * suitability of this software for any purpose. It is provided "as is"
+ * without express or implied warranty.
+ */
+
+#include "ares_setup.h"
+#include "ares.h"
+#include "ares_private.h"
+
+#if defined(WIN32) && !defined(MSDOS)
+
+struct timeval ares__tvnow(void)
+{
+ /*
+ ** GetTickCount() is available on _all_ Windows versions from W95 up
+ ** to nowadays. Returns milliseconds elapsed since last system boot,
+ ** increases monotonically and wraps once 49.7 days have elapsed.
+ */
+ struct timeval now;
+ DWORD milliseconds = GetTickCount();
+ now.tv_sec = milliseconds / 1000;
+ now.tv_usec = (milliseconds % 1000) * 1000;
+ return now;
+}
+
+#elif defined(HAVE_CLOCK_GETTIME_MONOTONIC)
+
+struct timeval ares__tvnow(void)
+{
+ /*
+ ** clock_gettime() is granted to be increased monotonically when the
+ ** monotonic clock is queried. Time starting point is unspecified, it
+ ** could be the system start-up time, the Epoch, or something else,
+ ** in any case the time starting point does not change once that the
+ ** system has started up.
+ */
+ struct timeval now;
+ struct timespec tsnow;
+ if(0 == clock_gettime(CLOCK_MONOTONIC, &tsnow)) {
+ now.tv_sec = tsnow.tv_sec;
+ now.tv_usec = tsnow.tv_nsec / 1000;
+ }
+ /*
+ ** Even when the configure process has truly detected monotonic clock
+ ** availability, it might happen that it is not actually available at
+ ** run-time. When this occurs simply fallback to other time source.
+ */
+#ifdef HAVE_GETTIMEOFDAY
+ else
+ (void)gettimeofday(&now, NULL); /* LCOV_EXCL_LINE */
+#else
+ else {
+ now.tv_sec = (long)time(NULL);
+ now.tv_usec = 0;
+ }
+#endif
+ return now;
+}
+
+#elif defined(HAVE_GETTIMEOFDAY)
+
+struct timeval ares__tvnow(void)
+{
+ /*
+ ** gettimeofday() is not granted to be increased monotonically, due to
+ ** clock drifting and external source time synchronization it can jump
+ ** forward or backward in time.
+ */
+ struct timeval now;
+ (void)gettimeofday(&now, NULL);
+ return now;
+}
+
+#else
+
+struct timeval ares__tvnow(void)
+{
+ /*
+ ** time() returns the value of time in seconds since the Epoch.
+ */
+ struct timeval now;
+ now.tv_sec = (long)time(NULL);
+ now.tv_usec = 0;
+ return now;
+}
+
+#endif
+
+#if 0 /* Not used */
+/*
+ * Make sure that the first argument is the more recent time, as otherwise
+ * we'll get a weird negative time-diff back...
+ *
+ * Returns: the time difference in number of milliseconds.
+ */
+long ares__tvdiff(struct timeval newer, struct timeval older)
+{
+ return (newer.tv_sec-older.tv_sec)*1000+
+ (newer.tv_usec-older.tv_usec)/1000;
+}
+#endif
+