lib/timer.h

   1 /*
   2  * Copyright (c) 2011, 2013 Nicira, Inc.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #ifndef TIMER_H
  18 #define TIMER_H 1
  19
  20 #include <stdbool.h>
  21
  22 #include "timeval.h"
  23 #include "util.h"
  24
  25 struct timer {
  26     long long int t;
  27 };
  28
  29 long long int timer_msecs_until_expired(const struct timer *);
  30 void timer_wait_at(const struct timer *, const char *where);
  31 #define timer_wait(timer) timer_wait_at(timer, OVS_SOURCE_LOCATOR)
  32
  33 /* Causes 'timer' to expire when 'duration' milliseconds have passed.
  34  *
  35  * May be used to initialize 'timer'. */
  36 static inline void
  37 timer_set_duration(struct timer *timer, long long int duration)
  38 {
  39     timer->t = time_msec() + duration;
  40 }
  41
  42 /* Causes 'timer' never to expire.
  43  *
  44  * May be used to initialize 'timer'. */
  45 static inline void
  46 timer_set_infinite(struct timer *timer)
  47 {
  48     timer->t = LLONG_MAX;
  49 }
  50
  51 /* Causes 'timer' to expire immediately.
  52  *
  53  * May be used to initialize 'timer'. */
  54 static inline void
  55 timer_set_expired(struct timer *timer)
  56 {
  57     timer->t = LLONG_MIN;
  58 }
  59
  60 /* True if 'timer' has expired. */
  61 static inline bool
  62 timer_expired(const struct timer *timer)
  63 {
  64     return time_msec() >= timer->t;
  65 }
  66
  67 /* Returns ture if 'timer' will never expire. */
  68 static inline bool
  69 timer_is_infinite(const struct timer *timer)
  70 {
  71     return timer->t == LLONG_MAX;
  72 }
  73
  74 #endif /* timer.h */