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- /*
- This file is part of GNUnet.
- Copyright (C) 2001-2013, 2018 GNUnet e.V.
- GNUnet is free software: you can redistribute it and/or modify it
- under the terms of the GNU Affero General Public License as published
- by the Free Software Foundation, either version 3 of the License,
- 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
- Affero General Public License for more details.
- You should have received a copy of the GNU Affero General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
- SPDX-License-Identifier: AGPL3.0-or-later
- */
- /**
- * @file util/time.c
- * @author Christian Grothoff
- * @brief functions for handling time and time arithmetic
- */
- #include "platform.h"
- #include "gnunet_util_lib.h"
- #if __STDC_NO_ATOMICS__
- #define ATOMIC
- #else
- #ifdef HAVE_STDATOMIC_H
- #include <stdatomic.h>
- #define ATOMIC _Atomic
- #else
- #define __STDC_NO_ATOMICS__ 1
- #define ATOMIC
- #endif
- #endif
- #define LOG(kind, ...) GNUNET_log_from (kind, "util-time", __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 timestamp offset for this instance.
- *
- * @return the offset we currently skew the locale time by
- */
- long long
- GNUNET_TIME_get_offset ()
- {
- return timestamp_offset;
- }
- /**
- * Round a time value so that it is suitable for transmission
- * via JSON encodings.
- *
- * @param at time to round
- * @return #GNUNET_OK if time was already rounded, #GNUNET_NO if
- * it was just now rounded
- */
- int
- GNUNET_TIME_round_abs (struct GNUNET_TIME_Absolute *at)
- {
- if (at->abs_value_us == GNUNET_TIME_UNIT_FOREVER_ABS.abs_value_us)
- return GNUNET_OK;
- if (0 == at->abs_value_us % 1000000)
- return GNUNET_OK;
- at->abs_value_us -= at->abs_value_us % 1000000;
- return GNUNET_NO;
- }
- /**
- * Round a time value so that it is suitable for transmission
- * via JSON encodings.
- *
- * @param rt time to round
- * @return #GNUNET_OK if time was already rounded, #GNUNET_NO if
- * it was just now rounded
- */
- int
- GNUNET_TIME_round_rel (struct GNUNET_TIME_Relative *rt)
- {
- if (rt->rel_value_us == GNUNET_TIME_UNIT_FOREVER_REL.rel_value_us)
- return GNUNET_OK;
- if (0 == rt->rel_value_us % 1000000)
- return GNUNET_OK;
- rt->rel_value_us -= rt->rel_value_us % 1000000;
- return GNUNET_NO;
- }
- /**
- * 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_us = (uint64_t) (((uint64_t) tv.tv_sec * 1000LL * 1000LL)
- + ((uint64_t) tv.tv_usec))
- + 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 1us.
- */
- struct GNUNET_TIME_Relative
- GNUNET_TIME_relative_get_unit_ ()
- {
- static struct GNUNET_TIME_Relative one = { 1 };
- return one;
- }
- /**
- * Return relative time of 1ms.
- */
- struct GNUNET_TIME_Relative
- GNUNET_TIME_relative_get_millisecond_ ()
- {
- static struct GNUNET_TIME_Relative one = { 1000 };
- return one;
- }
- /**
- * Return relative time of 1s.
- */
- struct GNUNET_TIME_Relative
- GNUNET_TIME_relative_get_second_ ()
- {
- static struct GNUNET_TIME_Relative one = { 1000 * 1000LL };
- return one;
- }
- /**
- * Return relative time of 1 minute.
- */
- struct GNUNET_TIME_Relative
- GNUNET_TIME_relative_get_minute_ ()
- {
- static struct GNUNET_TIME_Relative one = { 60 * 1000 * 1000LL };
- return one;
- }
- /**
- * Return relative time of 1 hour.
- */
- struct GNUNET_TIME_Relative
- GNUNET_TIME_relative_get_hour_ ()
- {
- static struct GNUNET_TIME_Relative one = { 60 * 60 * 1000 * 1000LL };
- 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_us == UINT64_MAX)
- return GNUNET_TIME_UNIT_FOREVER_ABS;
- struct GNUNET_TIME_Absolute now = GNUNET_TIME_absolute_get ();
- if (rel.rel_value_us + now.abs_value_us < rel.rel_value_us)
- {
- GNUNET_break (0); /* overflow... */
- return GNUNET_TIME_UNIT_FOREVER_ABS;
- }
- ret.abs_value_us = rel.rel_value_us + now.abs_value_us;
- 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_us < t2.rel_value_us) ? 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_us > t2.rel_value_us) ? 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_us < t2.abs_value_us) ? t1 : t2;
- }
- /**
- * Return the maximum of two relative time values.
- *
- * @param t1 first timestamp
- * @param t2 other timestamp
- * @return timestamp that is bigger
- */
- struct GNUNET_TIME_Absolute
- GNUNET_TIME_absolute_max (struct GNUNET_TIME_Absolute t1,
- struct GNUNET_TIME_Absolute t2)
- {
- return (t1.abs_value_us > t2.abs_value_us) ? 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_us == UINT64_MAX)
- return GNUNET_TIME_UNIT_FOREVER_REL;
- struct GNUNET_TIME_Absolute now = GNUNET_TIME_absolute_get ();
- if (now.abs_value_us > future.abs_value_us)
- return GNUNET_TIME_UNIT_ZERO;
- ret.rel_value_us = future.abs_value_us - now.abs_value_us;
- 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_us == UINT64_MAX)
- return GNUNET_TIME_UNIT_FOREVER_REL;
- if (end.abs_value_us < start.abs_value_us)
- return GNUNET_TIME_UNIT_ZERO;
- ret.rel_value_us = end.abs_value_us - start.abs_value_us;
- return ret;
- }
- /**
- * Get the duration of an operation as the
- * difference of the current time and the given start time "whence".
- *
- * @return 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 ();
- if (whence.abs_value_us > now.abs_value_us)
- return GNUNET_TIME_UNIT_ZERO;
- ret.rel_value_us = now.abs_value_us - whence.abs_value_us;
- 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_us == UINT64_MAX) ||
- (duration.rel_value_us == UINT64_MAX))
- return GNUNET_TIME_UNIT_FOREVER_ABS;
- if (start.abs_value_us + duration.rel_value_us < start.abs_value_us)
- {
- GNUNET_break (0);
- return GNUNET_TIME_UNIT_FOREVER_ABS;
- }
- ret.abs_value_us = start.abs_value_us + duration.rel_value_us;
- 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_us <= duration.rel_value_us)
- return GNUNET_TIME_UNIT_ZERO_ABS;
- if (start.abs_value_us == GNUNET_TIME_UNIT_FOREVER_ABS.abs_value_us)
- return GNUNET_TIME_UNIT_FOREVER_ABS;
- ret.abs_value_us = start.abs_value_us - duration.rel_value_us;
- 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 long long factor)
- {
- struct GNUNET_TIME_Relative ret;
- if (0 == factor)
- return GNUNET_TIME_UNIT_ZERO;
- if (rel.rel_value_us == GNUNET_TIME_UNIT_FOREVER_REL.rel_value_us)
- return GNUNET_TIME_UNIT_FOREVER_REL;
- ret.rel_value_us = rel.rel_value_us * factor;
- if (ret.rel_value_us / factor != rel.rel_value_us)
- {
- GNUNET_break (0);
- return GNUNET_TIME_UNIT_FOREVER_REL;
- }
- return ret;
- }
- /**
- * Multiply relative time by a given floating-point factor. The factor must be
- * positive.
- *
- * @return FOREVER if rel=FOREVER or on overflow; otherwise rel*factor
- */
- struct GNUNET_TIME_Relative
- relative_multiply_double (struct GNUNET_TIME_Relative rel, double factor)
- {
- struct GNUNET_TIME_Relative out;
- double m;
- GNUNET_assert (0 <= factor);
- if (0 == factor)
- return GNUNET_TIME_UNIT_ZERO;
- if (rel.rel_value_us == GNUNET_TIME_UNIT_FOREVER_REL.rel_value_us)
- return GNUNET_TIME_UNIT_FOREVER_REL;
- m = ((double) rel.rel_value_us) * factor;
- if (m >= (double) (GNUNET_TIME_UNIT_FOREVER_REL).rel_value_us)
- {
- GNUNET_break (0);
- return GNUNET_TIME_UNIT_FOREVER_REL;
- }
- out.rel_value_us = (uint64_t) m;
- return out;
- }
- /**
- * Saturating multiply relative time by a given factor.
- *
- * @param rel some duration
- * @param factor integer to multiply with
- * @return FOREVER if rel=FOREVER or on overflow; otherwise rel*factor
- */
- struct GNUNET_TIME_Relative
- GNUNET_TIME_relative_saturating_multiply (struct GNUNET_TIME_Relative rel,
- unsigned long long factor)
- {
- struct GNUNET_TIME_Relative ret;
- if (0 == factor)
- return GNUNET_TIME_UNIT_ZERO;
- if (rel.rel_value_us == GNUNET_TIME_UNIT_FOREVER_REL.rel_value_us)
- return GNUNET_TIME_UNIT_FOREVER_REL;
- ret.rel_value_us = rel.rel_value_us * factor;
- if (ret.rel_value_us / factor != rel.rel_value_us)
- {
- return GNUNET_TIME_UNIT_FOREVER_REL;
- }
- 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 long long factor)
- {
- struct GNUNET_TIME_Relative ret;
- if ((0 == factor) ||
- (rel.rel_value_us == GNUNET_TIME_UNIT_FOREVER_REL.rel_value_us))
- return GNUNET_TIME_UNIT_FOREVER_REL;
- ret.rel_value_us = rel.rel_value_us / 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 due;
- double exp;
- struct GNUNET_TIME_Relative ret;
- GNUNET_break (finished <= total);
- if (finished >= total)
- return GNUNET_TIME_UNIT_ZERO;
- if (0 == finished)
- return GNUNET_TIME_UNIT_FOREVER_REL;
- due = GNUNET_TIME_absolute_get_duration (start);
- exp = ((double) due.rel_value_us) * ((double) total) / ((double) finished);
- ret.rel_value_us = ((uint64_t) exp) - due.rel_value_us;
- 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_us == UINT64_MAX) || (a2.rel_value_us == UINT64_MAX))
- return GNUNET_TIME_UNIT_FOREVER_REL;
- if (a1.rel_value_us + a2.rel_value_us < a1.rel_value_us)
- {
- GNUNET_break (0);
- return GNUNET_TIME_UNIT_FOREVER_REL;
- }
- ret.rel_value_us = a1.rel_value_us + a2.rel_value_us;
- 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_us >= a1.rel_value_us)
- return GNUNET_TIME_UNIT_ZERO;
- if (a1.rel_value_us == UINT64_MAX)
- return GNUNET_TIME_UNIT_FOREVER_REL;
- ret.rel_value_us = a1.rel_value_us - a2.rel_value_us;
- 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_us__ = GNUNET_htonll (a.rel_value_us);
- 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_us = GNUNET_ntohll (a.rel_value_us__);
- 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_us__ = GNUNET_htonll (a.abs_value_us);
- 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_us = GNUNET_ntohll (a.abs_value_us__);
- return ret;
- }
- /**
- * Return the current year (i.e. '2011').
- */
- unsigned int
- GNUNET_TIME_get_current_year ()
- {
- time_t tp;
- struct tm *t;
- tp = time (NULL);
- t = gmtime (&tp);
- if (t == NULL)
- return 0;
- return t->tm_year + 1900;
- }
- /**
- * Convert an expiration time to the respective year (rounds)
- *
- * @param at absolute time
- * @return year a year (after 1970), 0 on error
- */
- unsigned int
- GNUNET_TIME_time_to_year (struct GNUNET_TIME_Absolute at)
- {
- struct tm *t;
- time_t tp;
- tp = at.abs_value_us / 1000LL / 1000LL; /* microseconds to seconds */
- t = gmtime (&tp);
- if (t == NULL)
- return 0;
- return t->tm_year + 1900;
- }
- /**
- * Convert a year to an expiration time of January 1st of that year.
- *
- * @param year a year (after 1970, please ;-)).
- * @return absolute time for January 1st of that year.
- */
- struct GNUNET_TIME_Absolute
- GNUNET_TIME_year_to_time (unsigned int year)
- {
- struct GNUNET_TIME_Absolute ret;
- time_t tp;
- struct tm t;
- memset (&t, 0, sizeof(t));
- if (year < 1900)
- {
- GNUNET_break (0);
- return GNUNET_TIME_absolute_get (); /* now */
- }
- t.tm_year = year - 1900;
- t.tm_mday = 1;
- t.tm_mon = 0;
- t.tm_wday = 1;
- t.tm_yday = 1;
- tp = mktime (&t);
- GNUNET_break (tp != (time_t) -1);
- ret.abs_value_us = tp * 1000LL * 1000LL; /* seconds to microseconds */
- return ret;
- }
- /**
- * Randomized exponential back-off, starting at 1 ms
- * and going up by a factor of 2+r, where 0 <= r <= 0.5, up
- * to a maximum of the given threshold.
- *
- * @param r current backoff time, initially zero
- * @param threshold maximum value for backoff
- * @return the next backoff time
- */
- struct GNUNET_TIME_Relative
- GNUNET_TIME_randomized_backoff (struct GNUNET_TIME_Relative rt,
- struct GNUNET_TIME_Relative threshold)
- {
- double r = (rand () % 500) / 1000.0;
- struct GNUNET_TIME_Relative t;
- t = relative_multiply_double (
- GNUNET_TIME_relative_max (GNUNET_TIME_UNIT_MILLISECONDS, rt),
- 2 + r);
- return GNUNET_TIME_relative_min (threshold, t);
- }
- /**
- * Return a random time value between 0.5*r and 1.5*r.
- *
- * @param r input time for scaling
- * @return randomized time
- */
- struct GNUNET_TIME_Relative
- GNUNET_TIME_randomize (struct GNUNET_TIME_Relative r)
- {
- double d = ((rand () % 1001) - 500) / 1000.0;
- return relative_multiply_double (r, d);
- }
- /**
- * Obtain the current time and make sure it is monotonically
- * increasing. Guards against systems without an RTC or
- * clocks running backwards and other nasty surprises. Does
- * not guarantee that the returned time is near the current
- * time returned by #GNUNET_TIME_absolute_get(). Two
- * subsequent calls (within a short time period) may return the
- * same value. Persists the last returned time on disk to
- * ensure that time never goes backwards. As a result, the
- * resulting value can be used to check if a message is the
- * "most recent" value and replays of older messages (from
- * the same origin) would be discarded.
- *
- * @param cfg configuration, used to determine where to
- * store the time; user can also insist RTC is working
- * nicely and disable the feature
- * @return monotonically increasing time
- */
- struct GNUNET_TIME_Absolute
- GNUNET_TIME_absolute_get_monotonic (
- const struct GNUNET_CONFIGURATION_Handle *cfg)
- {
- static const struct GNUNET_CONFIGURATION_Handle *last_cfg;
- static struct GNUNET_TIME_Absolute last_time;
- static struct GNUNET_DISK_MapHandle *map_handle;
- static ATOMIC volatile uint64_t *map;
- struct GNUNET_TIME_Absolute now;
- now = GNUNET_TIME_absolute_get ();
- if (last_cfg != cfg)
- {
- char *filename;
- if (NULL != map_handle)
- {
- GNUNET_DISK_file_unmap (map_handle);
- map_handle = NULL;
- }
- map = NULL;
- last_cfg = cfg;
- if ((NULL != cfg) &&
- (GNUNET_OK ==
- GNUNET_CONFIGURATION_get_value_filename (cfg,
- "util",
- "MONOTONIC_TIME_FILENAME",
- &filename)))
- {
- struct GNUNET_DISK_FileHandle *fh;
- fh = GNUNET_DISK_file_open (filename,
- GNUNET_DISK_OPEN_READWRITE
- | GNUNET_DISK_OPEN_CREATE,
- GNUNET_DISK_PERM_USER_WRITE
- | GNUNET_DISK_PERM_GROUP_WRITE
- | GNUNET_DISK_PERM_USER_READ
- | GNUNET_DISK_PERM_GROUP_READ);
- if (NULL == fh)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
- _ ("Failed to map `%s', cannot assure monotonic time!\n"),
- filename);
- }
- else
- {
- off_t size;
- size = 0;
- GNUNET_break (GNUNET_OK == GNUNET_DISK_file_handle_size (fh, &size));
- if (size < (off_t) sizeof(*map))
- {
- struct GNUNET_TIME_AbsoluteNBO o;
- o = GNUNET_TIME_absolute_hton (now);
- if (sizeof(o) != GNUNET_DISK_file_write (fh, &o, sizeof(o)))
- size = 0;
- else
- size = sizeof(o);
- }
- if (size == sizeof(*map))
- {
- map = GNUNET_DISK_file_map (fh,
- &map_handle,
- GNUNET_DISK_MAP_TYPE_READWRITE,
- sizeof(*map));
- if (NULL == map)
- GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
- _ (
- "Failed to map `%s', cannot assure monotonic time!\n"),
- filename);
- }
- else
- {
- GNUNET_log (
- GNUNET_ERROR_TYPE_WARNING,
- _ (
- "Failed to setup monotonic time file `%s', cannot assure monotonic time!\n"),
- filename);
- }
- }
- GNUNET_DISK_file_close (fh);
- GNUNET_free (filename);
- }
- }
- if (NULL != map)
- {
- struct GNUNET_TIME_AbsoluteNBO mt;
- #if __STDC_NO_ATOMICS__
- #if __GNUC__
- mt.abs_value_us__ = __sync_fetch_and_or (map, 0);
- #else
- mt.abs_value_us__ = *map; /* godspeed, pray this is atomic */
- #endif
- #else
- mt.abs_value_us__ = atomic_load (map);
- #endif
- last_time =
- GNUNET_TIME_absolute_max (GNUNET_TIME_absolute_ntoh (mt), last_time);
- }
- if (now.abs_value_us <= last_time.abs_value_us)
- now.abs_value_us = last_time.abs_value_us + 1;
- last_time = now;
- if (NULL != map)
- {
- uint64_t val = GNUNET_TIME_absolute_hton (now).abs_value_us__;
- #if __STDC_NO_ATOMICS__
- #if __GNUC__
- (void) __sync_lock_test_and_set (map, val);
- #else
- *map = val; /* godspeed, pray this is atomic */
- #endif
- #else
- atomic_store (map, val);
- #endif
- }
- return now;
- }
- /**
- * Destructor
- */
- void __attribute__ ((destructor))
- GNUNET_util_time_fini ()
- {
- (void) GNUNET_TIME_absolute_get_monotonic (NULL);
- }
- /* end of time.c */
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