src/systime.h

   1 /* systime.h - System-dependent definitions for time manipulations.
   2    Copyright (C) 1993-1994, 2002-2013 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 #include <timespec.h>
  23
  24 INLINE_HEADER_BEGIN
  25 #ifndef SYSTIME_INLINE
  26 # define SYSTIME_INLINE INLINE
  27 #endif
  28
  29 #ifdef emacs
  30 # ifdef HAVE_X_WINDOWS
  31 #  include <X11/X.h>
  32 # else
  33 typedef unsigned long Time;
  34 # endif
  35 #endif
  36
  37 /* On some configurations (hpux8.0, X11R4), sys/time.h and X11/Xos.h
  38    disagree about the name of the guard symbol.  */
  39 #ifdef HPUX
  40 #ifdef _STRUCT_TIMEVAL
  41 #ifndef __TIMEVAL__
  42 #define __TIMEVAL__
  43 #endif
  44 #endif
  45 #endif
  46
  47 #include <sys/time.h>   /* for 'struct timeval' */
  48 \f
  49 /* Emacs uses struct timespec to represent nonnegative temporal intervals.
  50
  51    WARNING: Since tv_sec might be an unsigned value, do not use struct
  52    timespec as a general-purpose data type for adding or subtracting
  53    arbitrary time values!  When computing A + B or A - B, typically A
  54    should be an absolute time since the epoch and B a nonnegative offset.  */
  55
  56 /* Return an invalid timespec.  */
  57 SYSTIME_INLINE struct timespec
  58 invalid_timespec (void)
  59 {
  60   return make_timespec (0, -1);
  61 }
  62
  63 /* Return 1 if TIME is a valid timespec.  This currently doesn't worry
  64    about whether tv_nsec is less than TIMESPEC_RESOLUTION; leap seconds
  65    might cause a problem if it did.  */
  66 SYSTIME_INLINE int
  67 timespec_valid_p (struct timespec t)
  68 {
  69   return t.tv_nsec >= 0;
  70 }
  71
  72 /* Return current system time.  */
  73 SYSTIME_INLINE struct timespec
  74 current_timespec (void)
  75 {
  76   struct timespec r;
  77   gettime (&r);
  78   return r;
  79 }
  80
  81 /* defined in sysdep.c */
  82 extern int set_file_times (int, const char *, struct timespec, struct timespec);
  83 extern struct timeval make_timeval (struct timespec) ATTRIBUTE_CONST;
  84
  85 /* defined in keyboard.c */
  86 extern void set_waiting_for_input (struct timespec *);
  87
  88 /* When lisp.h is not included Lisp_Object is not defined (this can
  89    happen when this files is used outside the src directory).
  90    Use GCPRO1 to determine if lisp.h was included.  */
  91 #ifdef GCPRO1
  92 /* defined in editfns.c */
  93 extern Lisp_Object make_lisp_time (struct timespec);
  94 extern bool decode_time_components (Lisp_Object, Lisp_Object, Lisp_Object,
  95                                     Lisp_Object, struct timespec *, double *);
  96 extern struct timespec lisp_time_argument (Lisp_Object);
  97 #endif
  98
  99 INLINE_HEADER_END
 100
 101 #endif /* EMACS_SYSTIME_H */