gettimeofday.h

来自「rtptools-1.18.tar.gz rtp generator」· C头文件 代码 · 共 71 行

#ifndef GETTIMEOFDAY_H_
#define GETTIMEOFDAY_H_
/***************************************************************************
 *
 * Header file for gettimeofday() function.
 *  gettimeofday.h
 *
 *  Copyright 2001 by Columbia University; all rights reserved
 *  by Akira Tsukamoto
 *
 ***************************************************************************/

#include "sysdep.h"

#ifdef  __cplusplus
extern "C" {
#endif

#ifndef HAVE_GETTIMEOFDAY
extern int gettimeofday(struct timeval *tv, void *t);
#endif

/* This portion is a copy from GNU library. <sys/time.h> */
/* Convenience macros for operations on timevals.
   NOTE: `timercmp' does not work for >= or <=.  */
#ifndef timerisset
#define timerisset(tvp)        ((tvp)->tv_sec || (tvp)->tv_usec)
#endif

#ifndef timerclear
#define timerclear(tvp)        ((tvp)->tv_sec = (tvp)->tv_usec = 0)
#endif

#ifndef timercmp
#define timercmp(a, b, CMP)                                                  \
  (((a)->tv_sec == (b)->tv_sec) ?                                             \
   ((a)->tv_usec CMP (b)->tv_usec) :                                          \
   ((a)->tv_sec CMP (b)->tv_sec))
#endif

#ifndef timeradd
#define timeradd(a, b, result)                                               \
  do {                                                                        \
    (result)->tv_sec = (a)->tv_sec + (b)->tv_sec;                             \
    (result)->tv_usec = (a)->tv_usec + (b)->tv_usec;                          \
    if ((result)->tv_usec >= 1000000)                                         \
      {                                                                       \
        ++(result)->tv_sec;                                                   \
        (result)->tv_usec -= 1000000;                                         \
      }                                                                       \
  } while (0)
#endif

#ifndef timersub
#define timersub(a, b, result)                                               \
  do {                                                                        \
    (result)->tv_sec = (a)->tv_sec - (b)->tv_sec;                             \
    (result)->tv_usec = (a)->tv_usec - (b)->tv_usec;                          \
    if ((result)->tv_usec < 0) {                                              \
      --(result)->tv_sec;                                                     \
      (result)->tv_usec += 1000000;                                           \
    }                                                                         \
  } while (0)
#endif

#ifdef  __cplusplus
}
#endif

#endif /* GETTIMEOFDAY_H_ */