src/systime.h

   1 /* systime.h - System-dependent definitions for time manipulations.
   2    Copyright (C) 1993-1994, 2002-2011 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 3 of the License, or
   9 (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef EMACS_SYSTIME_H
  20 #define EMACS_SYSTIME_H
  21
  22 #ifdef TIME_WITH_SYS_TIME
  23 #include <sys/time.h>
  24 #include <time.h>
  25 #else
  26 #ifdef HAVE_SYS_TIME_H
  27 #include <sys/time.h>
  28 #else
  29 #include <time.h>
  30 #endif
  31 #endif
  32
  33 #ifdef HAVE_TZNAME
  34 #ifndef tzname          /* For SGI.  */
  35 extern char *tzname[];  /* RS6000 and others want it this way.  */
  36 #endif
  37 #endif
  38
  39 /* SVr4 doesn't actually declare this in its #include files.  */
  40 #ifdef USG5_4
  41 extern time_t timezone;
  42 #endif
  43
  44 /* On some configurations (hpux8.0, X11R4), sys/time.h and X11/Xos.h
  45    disagree about the name of the guard symbol.  */
  46 #ifdef HPUX
  47 #ifdef _STRUCT_TIMEVAL
  48 #ifndef __TIMEVAL__
  49 #define __TIMEVAL__
  50 #endif
  51 #endif
  52 #endif
  53 \f
  54 /* EMACS_TIME is the type to use to represent temporal intervals -
  55    struct timeval on some systems, int on others.  It can be passed as
  56    the timeout argument to the select  system call.
  57
  58    EMACS_SECS (TIME) is an rvalue for the seconds component of TIME.
  59    EMACS_SET_SECS (TIME, SECONDS) sets that to SECONDS.
  60
  61    EMACS_HAS_USECS is defined if EMACS_TIME has a usecs component.
  62    EMACS_USECS (TIME) is an rvalue for the microseconds component of TIME.
  63         This returns zero if EMACS_TIME doesn't have a microseconds component.
  64    EMACS_SET_USECS (TIME, MICROSECONDS) sets that to MICROSECONDS.
  65         This does nothing if EMACS_TIME doesn't have a microseconds component.
  66
  67    EMACS_SET_SECS_USECS (TIME, SECS, USECS) sets both components of TIME.
  68
  69    EMACS_GET_TIME (TIME) stores the current system time in TIME, which
  70         should be an lvalue.
  71
  72    EMACS_ADD_TIME (DEST, SRC1, SRC2) adds SRC1 to SRC2 and stores the
  73         result in DEST.  SRC should not be negative.
  74
  75    EMACS_SUB_TIME (DEST, SRC1, SRC2) subtracts SRC2 from SRC1 and
  76         stores the result in DEST.  SRC should not be negative.
  77    EMACS_TIME_NEG_P (TIME) is true if TIME is negative.
  78
  79 */
  80
  81 #ifdef HAVE_TIMEVAL
  82
  83 #define EMACS_HAS_USECS
  84
  85 #define EMACS_TIME struct timeval
  86 #define EMACS_SECS(time)                    ((time).tv_sec  + 0)
  87 #define EMACS_USECS(time)                   ((time).tv_usec + 0)
  88 #define EMACS_SET_SECS(time, seconds)       ((time).tv_sec  = (seconds))
  89 #define EMACS_SET_USECS(time, microseconds) ((time).tv_usec = (microseconds))
  90
  91 /* On SVR4, the compiler may complain if given this extra BSD arg.  */
  92 #ifdef GETTIMEOFDAY_ONE_ARGUMENT
  93 #define EMACS_GET_TIME(time) gettimeofday (&(time))
  94 #else /* not GETTIMEOFDAY_ONE_ARGUMENT */
  95 /* Presumably the second arg is ignored.  */
  96 #define EMACS_GET_TIME(time) gettimeofday (&(time), NULL)
  97 #endif /* not GETTIMEOFDAY_ONE_ARGUMENT */
  98
  99 #define EMACS_ADD_TIME(dest, src1, src2)                \
 100   do {                                                  \
 101     (dest).tv_sec  = (src1).tv_sec  + (src2).tv_sec;    \
 102     (dest).tv_usec = (src1).tv_usec + (src2).tv_usec;   \
 103     if ((dest).tv_usec > 1000000)                       \
 104       (dest).tv_usec -= 1000000, (dest).tv_sec++;       \
 105   } while (0)
 106
 107 #define EMACS_SUB_TIME(dest, src1, src2)                \
 108   do {                                                  \
 109     (dest).tv_sec  = (src1).tv_sec  - (src2).tv_sec;    \
 110     (dest).tv_usec = (src1).tv_usec - (src2).tv_usec;   \
 111     if ((dest).tv_usec < 0)                             \
 112       (dest).tv_usec += 1000000, (dest).tv_sec--;       \
 113   } while (0)
 114
 115 #define EMACS_TIME_NEG_P(time)                                  \
 116   ((long)(time).tv_sec < 0                                      \
 117    || ((time).tv_sec == 0                                       \
 118        && (long)(time).tv_usec < 0))
 119
 120 #else /* ! defined (HAVE_TIMEVAL) */
 121
 122 #define EMACS_TIME int
 123 #define EMACS_SECS(time)                    (time)
 124 #define EMACS_USECS(time)                   0
 125 #define EMACS_SET_SECS(time, seconds)       ((time) = (seconds))
 126 #define EMACS_SET_USECS(time, usecs)        0
 127
 128 #define EMACS_GET_TIME(t) ((t) = time ((long *) 0))
 129 #define EMACS_ADD_TIME(dest, src1, src2) ((dest) = (src1) + (src2))
 130 #define EMACS_SUB_TIME(dest, src1, src2) ((dest) = (src1) - (src2))
 131 #define EMACS_TIME_NEG_P(t) ((t) < 0)
 132
 133 #endif /* ! defined (HAVE_TIMEVAL) */
 134
 135 #define EMACS_SET_SECS_USECS(time, secs, usecs)                 \
 136   (EMACS_SET_SECS (time, secs), EMACS_SET_USECS (time, usecs))
 137
 138 extern int set_file_times (const char *, EMACS_TIME, EMACS_TIME);
 139
 140 /* defined in keyboard.c */
 141 extern void set_waiting_for_input (EMACS_TIME *);
 142
 143 /* When lisp.h is not included Lisp_Object is not defined (this can
 144    happen when this files is used outside the src directory).
 145    Use GCPRO1 to determine if lisp.h was included.  */
 146 #ifdef GCPRO1
 147 /* defined in dired.c */
 148 extern Lisp_Object make_time (time_t);
 149
 150 /* defined in editfns.c*/
 151 extern int lisp_time_argument (Lisp_Object, time_t *, int *);
 152 #endif
 153
 154 /* Compare times T1 and T2.  Value is 0 if T1 and T2 are the same.
 155    Value is < 0 if T1 is less than T2.  Value is > 0 otherwise.  (Cast
 156    to long is for those platforms where time_t is an unsigned
 157    type, and where otherwise T1 will always be grater than T2.)  */
 158
 159 #define EMACS_TIME_CMP(T1, T2)                          \
 160   ((long)EMACS_SECS (T1) - (long)EMACS_SECS (T2)        \
 161    + (EMACS_SECS (T1) == EMACS_SECS (T2)                \
 162       ? EMACS_USECS (T1) - EMACS_USECS (T2)             \
 163       : 0))
 164
 165 /* Compare times T1 and T2 for equality, inequality etc.  */
 166
 167 #define EMACS_TIME_EQ(T1, T2) (EMACS_TIME_CMP (T1, T2) == 0)
 168 #define EMACS_TIME_NE(T1, T2) (EMACS_TIME_CMP (T1, T2) != 0)
 169 #define EMACS_TIME_GT(T1, T2) (EMACS_TIME_CMP (T1, T2) > 0)
 170 #define EMACS_TIME_GE(T1, T2) (EMACS_TIME_CMP (T1, T2) >= 0)
 171 #define EMACS_TIME_LT(T1, T2) (EMACS_TIME_CMP (T1, T2) < 0)
 172 #define EMACS_TIME_LE(T1, T2) (EMACS_TIME_CMP (T1, T2) <= 0)
 173
 174 #endif /* EMACS_SYSTIME_H */
 175