Imported Upstream version 0.9.2upstream/0.9.2

1 files changed, 521 insertions, 0 deletions

diff --git a/src/util/time.c b/src/util/time.c
new file mode 100644
index 0000000..c57ccd1
--- /dev/null
+++ b/src/util/time.c
@@ -0,0 +1,521 @@
+/*
+     This file is part of GNUnet.
+     (C) 2001, 2002, 2006, 2009 Christian Grothoff (and other contributing authors)
+
+     GNUnet 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 2, or (at your
+     option) any later version.
+
+     GNUnet 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 GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+*/
+
+/**
+ * @file util/time.c
+ * @author Christian Grothoff
+ * @brief functions for handling time and time arithmetic
+ */
+#include "platform.h"
+#include "gnunet_time_lib.h"
+
+#define LOG(kind,...) GNUNET_log_from (kind, "util", __VA_ARGS__)
+
+/**
+ * Variable used to simulate clock skew.  Used for testing, never in production.
+ */
+static long long timestamp_offset;
+
+/**
+ * Set the timestamp offset for this instance.
+ *
+ * @param offset the offset to skew the locale time by
+ */
+void
+GNUNET_TIME_set_offset (long long offset)
+{
+  timestamp_offset = offset;
+}
+
+/**
+ * Get the current time (works just as "time", just that we use the
+ * unit of time that the cron-jobs use (and is 64 bit)).
+ *
+ * @return the current time
+ */
+struct GNUNET_TIME_Absolute
+GNUNET_TIME_absolute_get ()
+{
+  struct GNUNET_TIME_Absolute ret;
+  struct timeval tv;
+
+  GETTIMEOFDAY (&tv, NULL);
+  ret.abs_value =
+      (uint64_t) (((uint64_t) tv.tv_sec * 1000LL) +
+                  ((uint64_t) tv.tv_usec / 1000LL)) + timestamp_offset;
+  return ret;
+}
+
+
+/**
+ * Return relative time of 0ms.
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_relative_get_zero ()
+{
+  static struct GNUNET_TIME_Relative zero;
+
+  return zero;
+}
+
+
+/**
+ * Return absolute time of 0ms.
+ */
+struct GNUNET_TIME_Absolute
+GNUNET_TIME_absolute_get_zero ()
+{
+  static struct GNUNET_TIME_Absolute zero;
+
+  return zero;
+}
+
+/**
+ * Return relative time of 1ms.
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_relative_get_unit ()
+{
+  static struct GNUNET_TIME_Relative one = { 1 };
+  return one;
+}
+
+/**
+ * Return "forever".
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_relative_get_forever ()
+{
+  static struct GNUNET_TIME_Relative forever = { UINT64_MAX };
+  return forever;
+}
+
+/**
+ * Return "forever".
+ */
+struct GNUNET_TIME_Absolute
+GNUNET_TIME_absolute_get_forever ()
+{
+  static struct GNUNET_TIME_Absolute forever = { UINT64_MAX };
+  return forever;
+}
+
+/**
+ * Convert relative time to an absolute time in the
+ * future.
+ *
+ * @return timestamp that is "rel" in the future, or FOREVER if rel==FOREVER (or if we would overflow)
+ */
+struct GNUNET_TIME_Absolute
+GNUNET_TIME_relative_to_absolute (struct GNUNET_TIME_Relative rel)
+{
+  struct GNUNET_TIME_Absolute ret;
+
+  if (rel.rel_value == UINT64_MAX)
+    return GNUNET_TIME_absolute_get_forever ();
+  struct GNUNET_TIME_Absolute now = GNUNET_TIME_absolute_get ();
+
+  if (rel.rel_value + now.abs_value < rel.rel_value)
+  {
+    GNUNET_break (0);           /* overflow... */
+    return GNUNET_TIME_absolute_get_forever ();
+  }
+  ret.abs_value = rel.rel_value + now.abs_value;
+  return ret;
+}
+
+
+/**
+ * Return the minimum of two relative time values.
+ *
+ * @param t1 first timestamp
+ * @param t2 other timestamp
+ * @return timestamp that is smaller
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_relative_min (struct GNUNET_TIME_Relative t1,
+                          struct GNUNET_TIME_Relative t2)
+{
+  return (t1.rel_value < t2.rel_value) ? t1 : t2;
+}
+
+
+/**
+ * Return the maximum of two relative time values.
+ *
+ * @param t1 first timestamp
+ * @param t2 other timestamp
+ * @return timestamp that is larger
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_relative_max (struct GNUNET_TIME_Relative t1,
+                          struct GNUNET_TIME_Relative t2)
+{
+  return (t1.rel_value > t2.rel_value) ? t1 : t2;
+}
+
+
+
+/**
+ * Return the minimum of two relative time values.
+ *
+ * @param t1 first timestamp
+ * @param t2 other timestamp
+ * @return timestamp that is smaller
+ */
+struct GNUNET_TIME_Absolute
+GNUNET_TIME_absolute_min (struct GNUNET_TIME_Absolute t1,
+                          struct GNUNET_TIME_Absolute t2)
+{
+  return (t1.abs_value < t2.abs_value) ? t1 : t2;
+}
+
+
+/**
+ * Return the maximum of two relative time values.
+ *
+ * @param t1 first timestamp
+ * @param t2 other timestamp
+ * @return timestamp that is smaller
+ */
+struct GNUNET_TIME_Absolute
+GNUNET_TIME_absolute_max (struct GNUNET_TIME_Absolute t1,
+                          struct GNUNET_TIME_Absolute t2)
+{
+  return (t1.abs_value > t2.abs_value) ? t1 : t2;
+}
+
+
+/**
+ * Given a timestamp in the future, how much time
+ * remains until then?
+ *
+ * @return future - now, or 0 if now >= future, or FOREVER if future==FOREVER.
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_absolute_get_remaining (struct GNUNET_TIME_Absolute future)
+{
+  struct GNUNET_TIME_Relative ret;
+
+  if (future.abs_value == UINT64_MAX)
+    return GNUNET_TIME_relative_get_forever ();
+  struct GNUNET_TIME_Absolute now = GNUNET_TIME_absolute_get ();
+
+  if (now.abs_value > future.abs_value)
+    return GNUNET_TIME_relative_get_zero ();
+  ret.rel_value = future.abs_value - now.abs_value;
+  return ret;
+}
+
+/**
+ * Compute the time difference between the given start and end times.
+ * Use this function instead of actual subtraction to ensure that
+ * "FOREVER" and overflows are handled correctly.
+ *
+ * @return 0 if start >= end; FOREVER if end==FOREVER; otherwise end - start
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_absolute_get_difference (struct GNUNET_TIME_Absolute start,
+                                     struct GNUNET_TIME_Absolute end)
+{
+  struct GNUNET_TIME_Relative ret;
+
+  if (end.abs_value == UINT64_MAX)
+    return GNUNET_TIME_relative_get_forever ();
+  if (end.abs_value < start.abs_value)
+    return GNUNET_TIME_relative_get_zero ();
+  ret.rel_value = end.abs_value - start.abs_value;
+  return ret;
+}
+
+/**
+ * Get the duration of an operation as the
+ * difference of the current time and the given start time "whence".
+ *
+ * @return aborts if whence==FOREVER, 0 if whence > now, otherwise now-whence.
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_absolute_get_duration (struct GNUNET_TIME_Absolute whence)
+{
+  struct GNUNET_TIME_Absolute now;
+  struct GNUNET_TIME_Relative ret;
+
+  now = GNUNET_TIME_absolute_get ();
+  GNUNET_assert (whence.abs_value != UINT64_MAX);
+  if (whence.abs_value > now.abs_value)
+    return GNUNET_TIME_relative_get_zero ();
+  ret.rel_value = now.abs_value - whence.abs_value;
+  return ret;
+}
+
+
+/**
+ * Add a given relative duration to the
+ * given start time.
+ *
+ * @return FOREVER if either argument is FOREVER or on overflow; start+duration otherwise
+ */
+struct GNUNET_TIME_Absolute
+GNUNET_TIME_absolute_add (struct GNUNET_TIME_Absolute start,
+                          struct GNUNET_TIME_Relative duration)
+{
+  struct GNUNET_TIME_Absolute ret;
+
+  if ((start.abs_value == UINT64_MAX) || (duration.rel_value == UINT64_MAX))
+    return GNUNET_TIME_absolute_get_forever ();
+  if (start.abs_value + duration.rel_value < start.abs_value)
+  {
+    GNUNET_break (0);
+    return GNUNET_TIME_absolute_get_forever ();
+  }
+  ret.abs_value = start.abs_value + duration.rel_value;
+  return ret;
+}
+
+
+/**
+ * Subtract a given relative duration from the
+ * given start time.
+ *
+ * @param start some absolute time
+ * @param duration some relative time to subtract
+ * @return ZERO if start <= duration, or FOREVER if start time is FOREVER; start-duration otherwise
+ */
+struct GNUNET_TIME_Absolute
+GNUNET_TIME_absolute_subtract (struct GNUNET_TIME_Absolute start,
+                               struct GNUNET_TIME_Relative duration)
+{
+  struct GNUNET_TIME_Absolute ret;
+
+  if (start.abs_value <= duration.rel_value)
+    return GNUNET_TIME_UNIT_ZERO_ABS;
+  if (start.abs_value == GNUNET_TIME_UNIT_FOREVER_ABS.abs_value)
+    return GNUNET_TIME_UNIT_FOREVER_ABS;
+  ret.abs_value = start.abs_value - duration.rel_value;
+  return ret;
+}
+
+
+/**
+ * Multiply relative time by a given factor.
+ *
+ * @return FOREVER if rel=FOREVER or on overflow; otherwise rel*factor
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_relative_multiply (struct GNUNET_TIME_Relative rel,
+                               unsigned int factor)
+{
+  struct GNUNET_TIME_Relative ret;
+
+  if (factor == 0)
+    return GNUNET_TIME_relative_get_zero ();
+  ret.rel_value = rel.rel_value * (unsigned long long) factor;
+  if (ret.rel_value / factor != rel.rel_value)
+  {
+    GNUNET_break (0);
+    return GNUNET_TIME_relative_get_forever ();
+  }
+  return ret;
+}
+
+
+/**
+ * Divide relative time by a given factor.
+ *
+ * @param rel some duration
+ * @param factor integer to divide by
+ * @return FOREVER if rel=FOREVER or factor==0; otherwise rel/factor
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_relative_divide (struct GNUNET_TIME_Relative rel,
+                             unsigned int factor)
+{
+  struct GNUNET_TIME_Relative ret;
+
+  if ((factor == 0) ||
+      (rel.rel_value == GNUNET_TIME_UNIT_FOREVER_REL.rel_value))
+    return GNUNET_TIME_UNIT_FOREVER_REL;
+  ret.rel_value = rel.rel_value / (unsigned long long) factor;
+  return ret;
+}
+
+
+/**
+ * Calculate the estimate time of arrival/completion
+ * for an operation.
+ *
+ * @param start when did the operation start?
+ * @param finished how much has been done?
+ * @param total how much must be done overall (same unit as for "finished")
+ * @return remaining duration for the operation,
+ *        assuming it continues at the same speed
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_calculate_eta (struct GNUNET_TIME_Absolute start, uint64_t finished,
+                           uint64_t total)
+{
+  struct GNUNET_TIME_Relative dur;
+  double exp;
+  struct GNUNET_TIME_Relative ret;
+
+  GNUNET_break (finished <= total);
+  if (finished >= total)
+    return GNUNET_TIME_UNIT_ZERO;
+  if (finished == 0)
+    return GNUNET_TIME_UNIT_FOREVER_REL;
+  dur = GNUNET_TIME_absolute_get_duration (start);
+  exp = ((double) dur.rel_value) * ((double) total) / ((double) finished);
+  ret.rel_value = ((uint64_t) exp) - dur.rel_value;
+  return ret;
+}
+
+
+/**
+ * Add relative times together.
+ *
+ * @param a1 first timestamp
+ * @param a2 second timestamp
+ * @return FOREVER if either argument is FOREVER or on overflow; a1+a2 otherwise
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_relative_add (struct GNUNET_TIME_Relative a1,
+                          struct GNUNET_TIME_Relative a2)
+{
+  struct GNUNET_TIME_Relative ret;
+
+  if ((a1.rel_value == UINT64_MAX) || (a2.rel_value == UINT64_MAX))
+    return GNUNET_TIME_relative_get_forever ();
+  if (a1.rel_value + a2.rel_value < a1.rel_value)
+  {
+    GNUNET_break (0);
+    return GNUNET_TIME_relative_get_forever ();
+  }
+  ret.rel_value = a1.rel_value + a2.rel_value;
+  return ret;
+}
+
+
+/**
+ * Subtract relative timestamp from the other.
+ *
+ * @param a1 first timestamp
+ * @param a2 second timestamp
+ * @return ZERO if a2>=a1 (including both FOREVER), FOREVER if a1 is FOREVER, a1-a2 otherwise
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_relative_subtract (struct GNUNET_TIME_Relative a1,
+                               struct GNUNET_TIME_Relative a2)
+{
+  struct GNUNET_TIME_Relative ret;
+
+  if (a2.rel_value >= a1.rel_value)
+    return GNUNET_TIME_relative_get_zero ();
+  if (a1.rel_value == UINT64_MAX)
+    return GNUNET_TIME_relative_get_forever ();
+  ret.rel_value = a1.rel_value - a2.rel_value;
+  return ret;
+}
+
+
+/**
+ * Convert relative time to network byte order.
+ *
+ * @param a time to convert
+ * @return time in network byte order
+ */
+struct GNUNET_TIME_RelativeNBO
+GNUNET_TIME_relative_hton (struct GNUNET_TIME_Relative a)
+{
+  struct GNUNET_TIME_RelativeNBO ret;
+
+  ret.rel_value__ = GNUNET_htonll (a.rel_value);
+  return ret;
+}
+
+/**
+ * Convert relative time from network byte order.
+ *
+ * @param a time to convert
+ * @return time in host byte order
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_relative_ntoh (struct GNUNET_TIME_RelativeNBO a)
+{
+  struct GNUNET_TIME_Relative ret;
+
+  ret.rel_value = GNUNET_ntohll (a.rel_value__);
+  return ret;
+
+}
+
+/**
+ * Convert absolute time to network byte order.
+ *
+ * @param a time to convert
+ * @return time in network byte order
+ */
+struct GNUNET_TIME_AbsoluteNBO
+GNUNET_TIME_absolute_hton (struct GNUNET_TIME_Absolute a)
+{
+  struct GNUNET_TIME_AbsoluteNBO ret;
+
+  ret.abs_value__ = GNUNET_htonll (a.abs_value);
+  return ret;
+}
+
+/**
+ * Convert absolute time from network byte order.
+ *
+ * @param a time to convert
+ * @return time in host byte order
+ */
+struct GNUNET_TIME_Absolute
+GNUNET_TIME_absolute_ntoh (struct GNUNET_TIME_AbsoluteNBO a)
+{
+  struct GNUNET_TIME_Absolute ret;
+
+  ret.abs_value = GNUNET_ntohll (a.abs_value__);
+  return ret;
+
+}
+
+/**
+ * Convert a relative time to a string.
+ * This is one of the very few calls in the entire API that is
+ * NOT reentrant!
+ *
+ * @param time the time to print
+ *
+ * @return string form of the time (as milliseconds)
+ */
+const char *
+GNUNET_TIME_relative_to_string (struct GNUNET_TIME_Relative time)
+{
+  static char time_string[21];
+
+  memset (time_string, 0, sizeof (time_string));
+
+  sprintf (time_string, "%llu", (unsigned long long) time.rel_value);
+  return (const char *) time_string;
+}
+
+
+
+/* end of time.c */