mirror of
https://git.haproxy.org/git/haproxy.git/
synced 2025-11-04 10:31:14 +01:00
889faf467b
Some of them were simply removed as unused (possibly some leftovers from an older cleanup session), some were turned to haproxy/bitops.h and a few had to be added (hlua.c and stick-table.h need standard.h for parse_time_err; htx.h requires chunk.h but used to get it through standard.h).
154 lines
4.7 KiB
C
154 lines
4.7 KiB
C
/*
|
|
include/common/ticks.h
|
|
Functions and macros for manipulation of expiration timers
|
|
|
|
Copyright (C) 2000-2009 Willy Tarreau - w@1wt.eu
|
|
|
|
This 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, version 2.1
|
|
exclusively.
|
|
|
|
This 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 this library; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
/*
|
|
* Using a mix of milliseconds and timeval for internal timers is expensive and
|
|
* overkill, because we don't need such a precision to compute timeouts.
|
|
* So we're converting them to "ticks".
|
|
*
|
|
* A tick is a representation of a date relative to another one, and is
|
|
* measured in milliseconds. The natural usage is to represent an absolute date
|
|
* relative to the current date. Since it is not practical to update all values
|
|
* each time the current date changes, instead we use the absolute date rounded
|
|
* down to fit in a tick. We then have to compare a tick to the current date to
|
|
* know whether it is in the future or in the past. If a tick is below the
|
|
* current date, it is in the past. If it is above, it is in the future. The
|
|
* values will wrap so we can't compare that easily, instead we check the sign
|
|
* of the difference between a tick and the current date.
|
|
*
|
|
* Proceeding like this allows us to manipulate dates that are stored in
|
|
* scalars with enough precision and range. For this reason, we store ticks in
|
|
* 32-bit integers. This is enough to handle dates that are between 24.85 days
|
|
* in the past and as much in the future.
|
|
*
|
|
* We must both support absolute dates (well in fact, dates relative to now+/-
|
|
* 24 days), and intervals (for timeouts). Both types need an "eternity" magic
|
|
* value. For optimal code generation, we'll use zero as the magic value
|
|
* indicating that an expiration timer or a timeout is not set. We have to
|
|
* check that we don't return this value when adding timeouts to <now>. If a
|
|
* computation returns 0, we must increase it to 1 (which will push the timeout
|
|
* 1 ms further). For this reason, timeouts must not be added by hand but via
|
|
* the dedicated tick_add() function.
|
|
*/
|
|
|
|
#ifndef _COMMON_TICKS_H
|
|
#define _COMMON_TICKS_H
|
|
|
|
#include <haproxy/api.h>
|
|
|
|
#define TICK_ETERNITY 0
|
|
|
|
/* right now, ticks are milliseconds. Both negative ms and negative ticks
|
|
* indicate eternity.
|
|
*/
|
|
#define MS_TO_TICKS(ms) (ms)
|
|
#define TICKS_TO_MS(tk) (tk)
|
|
|
|
/* return 1 if tick is set, otherwise 0 */
|
|
static inline int tick_isset(int expire)
|
|
{
|
|
return expire != 0;
|
|
}
|
|
|
|
/* Add <timeout> to <now>, and return the resulting expiration date.
|
|
* <timeout> will not be checked for null values.
|
|
*/
|
|
static inline int tick_add(int now, int timeout)
|
|
{
|
|
now += timeout;
|
|
if (unlikely(!now))
|
|
now++; /* unfortunate value */
|
|
return now;
|
|
}
|
|
|
|
/* add <timeout> to <now> if it is set, otherwise set it to eternity.
|
|
* Return the resulting expiration date.
|
|
*/
|
|
static inline int tick_add_ifset(int now, int timeout)
|
|
{
|
|
if (!timeout)
|
|
return TICK_ETERNITY;
|
|
return tick_add(now, timeout);
|
|
}
|
|
|
|
/* return 1 if timer <t1> is before <t2>, none of which can be infinite. */
|
|
static inline int tick_is_lt(int t1, int t2)
|
|
{
|
|
return (t1 - t2) < 0;
|
|
}
|
|
|
|
/* return 1 if timer <t1> is before or equal to <t2>, none of which can be infinite. */
|
|
static inline int tick_is_le(int t1, int t2)
|
|
{
|
|
return (t1 - t2) <= 0;
|
|
}
|
|
|
|
/* return 1 if timer <timer> is expired at date <now>, otherwise zero */
|
|
static inline int tick_is_expired(int timer, int now)
|
|
{
|
|
if (unlikely(!tick_isset(timer)))
|
|
return 0;
|
|
if (unlikely((timer - now) <= 0))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
/* return the first one of the two timers, both of which may be infinite */
|
|
static inline int tick_first(int t1, int t2)
|
|
{
|
|
if (!tick_isset(t1))
|
|
return t2;
|
|
if (!tick_isset(t2))
|
|
return t1;
|
|
if ((t1 - t2) <= 0)
|
|
return t1;
|
|
else
|
|
return t2;
|
|
}
|
|
|
|
/* return the first one of the two timers, where only the first one may be infinite */
|
|
static inline int tick_first_2nz(int t1, int t2)
|
|
{
|
|
if (!tick_isset(t1))
|
|
return t2;
|
|
if ((t1 - t2) <= 0)
|
|
return t1;
|
|
else
|
|
return t2;
|
|
}
|
|
|
|
/* return the number of ticks remaining from <now> to <exp>, or zero if expired */
|
|
static inline int tick_remain(int now, int exp)
|
|
{
|
|
if (tick_is_expired(exp, now))
|
|
return 0;
|
|
return exp - now;
|
|
}
|
|
|
|
#endif /* _COMMON_TICKS_H */
|
|
|
|
/*
|
|
* Local variables:
|
|
* c-indent-level: 8
|
|
* c-basic-offset: 8
|
|
* End:
|
|
*/
|