src/lib/wallclock/timeval.h

   1 /* Copyright (c) 2003-2004, Roger Dingledine
   2  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
   3  * Copyright (c) 2007-2019, The Tor Project, Inc. */
   4 /* See LICENSE for licensing information */
   5
   6 /**
   7  * \file timeval.h
   8  *
   9  * \brief Declarations for timeval-related macros that some platforms
  10  * are missing.
  11  **/
  12
  13 #ifndef TOR_TIMEVAL_H
  14 #define TOR_TIMEVAL_H
  15
  16 #include "orconfig.h"
  17 #include "lib/cc/torint.h"
  18
  19 #ifdef HAVE_SYS_TIME_H
  20 #include <sys/time.h>
  21 #endif
  22
  23 #ifndef timeradd
  24 /** Replacement for timeradd on platforms that do not have it: sets tvout to
  25  * the sum of tv1 and tv2. */
  26 #define timeradd(tv1,tv2,tvout) \
  27   do {                                                  \
  28     (tvout)->tv_sec = (tv1)->tv_sec + (tv2)->tv_sec;    \
  29     (tvout)->tv_usec = (tv1)->tv_usec + (tv2)->tv_usec; \
  30     if ((tvout)->tv_usec >= 1000000) {                  \
  31       (tvout)->tv_usec -= 1000000;                      \
  32       (tvout)->tv_sec++;                                \
  33     }                                                   \
  34   } while (0)
  35 #endif /* !defined(timeradd) */
  36
  37 #ifndef timersub
  38 /** Replacement for timersub on platforms that do not have it: sets tvout to
  39  * tv1 minus tv2. */
  40 #define timersub(tv1,tv2,tvout) \
  41   do {                                                  \
  42     (tvout)->tv_sec = (tv1)->tv_sec - (tv2)->tv_sec;    \
  43     (tvout)->tv_usec = (tv1)->tv_usec - (tv2)->tv_usec; \
  44     if ((tvout)->tv_usec < 0) {                         \
  45       (tvout)->tv_usec += 1000000;                      \
  46       (tvout)->tv_sec--;                                \
  47     }                                                   \
  48   } while (0)
  49 #endif /* !defined(timersub) */
  50
  51 #ifndef timercmp
  52 /** Replacement for timercmp on platforms that do not have it: returns true
  53  * iff the relational operator "op" makes the expression tv1 op tv2 true.
  54  *
  55  * Note that while this definition should work for all boolean operators, some
  56  * platforms' native timercmp definitions do not support >=, <=, or ==.  So
  57  * don't use those.
  58  */
  59 #define timercmp(tv1,tv2,op)                    \
  60   (((tv1)->tv_sec == (tv2)->tv_sec) ?           \
  61    ((tv1)->tv_usec op (tv2)->tv_usec) :         \
  62    ((tv1)->tv_sec op (tv2)->tv_sec))
  63 #endif /* !defined(timercmp) */
  64
  65 #endif