src/systime.h

   1 /* systime.h - System-dependent definitions for time manipulations.
   2    Copyright (C) 1992 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 1, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 #ifdef TIME_WITH_SYS_TIME
  21 #include <sys/time.h>
  22 #include <time.h>
  23 #else
  24 #ifdef HAVE_SYS_TIME_H
  25 #include <sys/time.h>
  26 #else
  27 #include <time.h>
  28 #endif
  29 #endif
  30
  31 /* SVr4 doesn't actually declare this in its #include files.  */
  32 #ifdef USG5_4
  33 extern long timezone;
  34 #endif
  35
  36 #ifdef VMS
  37 #ifdef VAXC
  38 #include "vmstime.h"
  39 #endif
  40 #endif
  41
  42 \f
  43 /* EMACS_TIME is the type to use to represent temporal intervals -
  44    struct timeval on some systems, int on others.  It can be passed as
  45    the timeout argument to the select  system call.
  46
  47    EMACS_SECS (TIME) is an rvalue for the seconds component of TIME.
  48    EMACS_SET_SECS (TIME, SECONDS) sets that to SECONDS.
  49
  50    EMACS_HAS_USECS is defined iff EMACS_TIME has a usecs component.
  51    EMACS_USECS (TIME) is an rvalue for the microseconds component of TIME.
  52         This returns zero if EMACS_TIME doesn't have a microseconds component.
  53    EMACS_SET_USECS (TIME, MICROSECONDS) sets that to MICROSECONDS.
  54         This does nothing if EMACS_TIME doesn't have a microseconds component.
  55
  56    EMACS_SET_SECS_USECS (TIME, SECS, USECS) sets both components of TIME.
  57
  58    EMACS_GET_TIME (TIME) stores the current system time in TIME, which
  59         should be an lvalue.
  60    EMACS_SET_UTIMES (PATH, ATIME, MTIME) changes the last-access and
  61         last-modification times of the file named PATH to ATIME and
  62         MTIME, which are EMACS_TIMEs.
  63
  64    EMACS_ADD_TIME (DEST, SRC1, SRC2) adds SRC1 to SRC2 and stores the
  65         result in DEST.  SRC should not be negative.
  66
  67    EMACS_SUB_TIME (DEST, SRC1, SRC2) subtracts SRC2 from SRC1 and
  68         stores the result in DEST.  SRC should not be negative.
  69    EMACS_TIME_NEG_P (TIME) is true iff TIME is negative.
  70
  71 */
  72
  73 #ifdef HAVE_TIMEVAL
  74
  75 #define EMACS_HAS_USECS
  76
  77 #define EMACS_TIME struct timeval
  78 #define EMACS_SECS(time)                    ((time).tv_sec  + 0)
  79 #define EMACS_USECS(time)                   ((time).tv_usec + 0)
  80 #define EMACS_SET_SECS(time, seconds)       ((time).tv_sec  = (seconds))
  81 #define EMACS_SET_USECS(time, microseconds) ((time).tv_usec = (microseconds))
  82
  83 #define EMACS_GET_TIME(time)                                    \
  84 {                                                               \
  85   struct timezone dummy;                                        \
  86   gettimeofday (&(time), &dummy);                               \
  87 }
  88
  89 #define EMACS_ADD_TIME(dest, src1, src2)                        \
  90 {                                                               \
  91   (dest).tv_sec  = (src1).tv_sec  + (src2).tv_sec;              \
  92   (dest).tv_usec = (src1).tv_usec + (src2).tv_usec;             \
  93   if ((dest).tv_usec > 1000000)                                 \
  94     (dest).tv_usec -= 1000000, (dest).tv_sec++;                 \
  95 }
  96
  97 #define EMACS_SUB_TIME(dest, src1, src2)                        \
  98 {                                                               \
  99   (dest).tv_sec  = (src1).tv_sec  - (src2).tv_sec;              \
 100   (dest).tv_usec = (src1).tv_usec - (src2).tv_usec;             \
 101   if ((dest).tv_usec < 0)                                       \
 102     (dest).tv_usec += 1000000, (dest).tv_sec--;                 \
 103 }
 104
 105 #define EMACS_TIME_NEG_P(time)                                  \
 106   ((time).tv_sec < 0                                            \
 107    || ((time).tv_sec == 0                                       \
 108        && (time).tv_usec < 0))
 109
 110 #else /* ! defined (HAVE_TIMEVAL) */
 111
 112 #define EMACS_TIME int
 113 #define EMACS_SECS(time)                    (time)
 114 #define EMACS_USECS(time)                   0
 115 #define EMACS_SET_SECS(time, seconds)       ((time) = (seconds))
 116 #define EMACS_SET_USECS(time, usecs)        0
 117
 118 #define EMACS_GET_TIME(t) ((t) = time ((long *) 0))
 119 #define EMACS_ADD_TIME(dest, src1, src2) ((dest) = (src1) + (src2))
 120 #define EMACS_SUB_TIME(dest, src1, src2) ((dest) = (src1) - (src2))
 121 #define EMACS_TIME_NEG_P(t) ((t) < 0)
 122
 123 #endif /* ! defined (HAVE_TIMEVAL) */
 124
 125 #define EMACS_SET_SECS_USECS(time, secs, usecs)                 \
 126   (EMACS_SET_SECS (time, secs), EMACS_SET_USECS (time, usecs))
 127
 128 #ifdef USE_UTIME
 129
 130 #define EMACS_SET_UTIMES(path, atime, mtime)                    \
 131   {                                                             \
 132     time_t tv[2];                                               \
 133     tv[0] = EMACS_SECS (atime);                                 \
 134     tv[1] = EMACS_SECS (mtime);                                 \
 135     utime ((path), tv);                                         \
 136   }
 137
 138 #else /* ! defined (USE_UTIME) */
 139
 140 #define EMACS_SET_UTIMES(path, atime, mtime)                    \
 141   {                                                             \
 142     EMACS_TIME tv[2];                                           \
 143     tv[0] = atime;                                              \
 144     tv[1] = mtime;                                              \
 145     utimes ((path), tv);                                        \
 146   }
 147
 148 #endif /* ! defined (USE_UTIME) */