bed9ed4aa7178374d74d575864d9e37b2af9cc91
[bpt/emacs.git] / 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 emacs
34 # ifdef HAVE_X_WINDOWS
35 # include <X11/X.h>
36 # else
37 typedef unsigned long Time;
38 # endif
39 #endif
40
41 #ifdef HAVE_TZNAME
42 #ifndef tzname /* For SGI. */
43 extern char *tzname[]; /* RS6000 and others want it this way. */
44 #endif
45 #endif
46
47 /* SVr4 doesn't actually declare this in its #include files. */
48 #ifdef USG5_4
49 extern time_t timezone;
50 #endif
51
52 /* On some configurations (hpux8.0, X11R4), sys/time.h and X11/Xos.h
53 disagree about the name of the guard symbol. */
54 #ifdef HPUX
55 #ifdef _STRUCT_TIMEVAL
56 #ifndef __TIMEVAL__
57 #define __TIMEVAL__
58 #endif
59 #endif
60 #endif
61 \f
62 /* EMACS_TIME is the type to use to represent temporal intervals -
63 struct timeval on some systems, int on others. It can be passed as
64 the timeout argument to the select system call.
65
66 EMACS_SECS (TIME) is an rvalue for the seconds component of TIME.
67 EMACS_SET_SECS (TIME, SECONDS) sets that to SECONDS.
68
69 EMACS_HAS_USECS is defined if EMACS_TIME has a usecs component.
70 EMACS_USECS (TIME) is an rvalue for the microseconds component of TIME.
71 This returns zero if EMACS_TIME doesn't have a microseconds component.
72 EMACS_SET_USECS (TIME, MICROSECONDS) sets that to MICROSECONDS.
73 This does nothing if EMACS_TIME doesn't have a microseconds component.
74
75 EMACS_SET_SECS_USECS (TIME, SECS, USECS) sets both components of TIME.
76
77 EMACS_GET_TIME (TIME) stores the current system time in TIME, which
78 should be an lvalue.
79
80 EMACS_ADD_TIME (DEST, SRC1, SRC2) adds SRC1 to SRC2 and stores the
81 result in DEST. SRC should not be negative.
82
83 EMACS_SUB_TIME (DEST, SRC1, SRC2) subtracts SRC2 from SRC1 and
84 stores the result in DEST. SRC should not be negative.
85 EMACS_TIME_NEG_P (TIME) is true if TIME is negative.
86
87 */
88
89 #ifdef HAVE_TIMEVAL
90
91 #define EMACS_HAS_USECS
92
93 #define EMACS_TIME struct timeval
94 #define EMACS_SECS(time) ((time).tv_sec + 0)
95 #define EMACS_USECS(time) ((time).tv_usec + 0)
96 #define EMACS_SET_SECS(time, seconds) ((time).tv_sec = (seconds))
97 #define EMACS_SET_USECS(time, microseconds) ((time).tv_usec = (microseconds))
98
99 /* On SVR4, the compiler may complain if given this extra BSD arg. */
100 #ifdef GETTIMEOFDAY_ONE_ARGUMENT
101 #define EMACS_GET_TIME(time) gettimeofday (&(time))
102 #else /* not GETTIMEOFDAY_ONE_ARGUMENT */
103 /* Presumably the second arg is ignored. */
104 #define EMACS_GET_TIME(time) gettimeofday (&(time), NULL)
105 #endif /* not GETTIMEOFDAY_ONE_ARGUMENT */
106
107 #define EMACS_ADD_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 > 1000000) \
112 (dest).tv_usec -= 1000000, (dest).tv_sec++; \
113 } while (0)
114
115 #define EMACS_SUB_TIME(dest, src1, src2) \
116 do { \
117 (dest).tv_sec = (src1).tv_sec - (src2).tv_sec; \
118 (dest).tv_usec = (src1).tv_usec - (src2).tv_usec; \
119 if ((dest).tv_usec < 0) \
120 (dest).tv_usec += 1000000, (dest).tv_sec--; \
121 } while (0)
122
123 #define EMACS_TIME_NEG_P(time) \
124 ((long)(time).tv_sec < 0 \
125 || ((time).tv_sec == 0 \
126 && (long)(time).tv_usec < 0))
127
128 #else /* ! defined (HAVE_TIMEVAL) */
129
130 #define EMACS_TIME int
131 #define EMACS_SECS(time) (time)
132 #define EMACS_USECS(time) 0
133 #define EMACS_SET_SECS(time, seconds) ((time) = (seconds))
134 #define EMACS_SET_USECS(time, usecs) 0
135
136 #define EMACS_GET_TIME(t) ((t) = time ((long *) 0))
137 #define EMACS_ADD_TIME(dest, src1, src2) ((dest) = (src1) + (src2))
138 #define EMACS_SUB_TIME(dest, src1, src2) ((dest) = (src1) - (src2))
139 #define EMACS_TIME_NEG_P(t) ((t) < 0)
140
141 #endif /* ! defined (HAVE_TIMEVAL) */
142
143 #define EMACS_SET_SECS_USECS(time, secs, usecs) \
144 (EMACS_SET_SECS (time, secs), EMACS_SET_USECS (time, usecs))
145
146 extern int set_file_times (const char *, EMACS_TIME, EMACS_TIME);
147
148 /* defined in keyboard.c */
149 extern void set_waiting_for_input (EMACS_TIME *);
150
151 /* When lisp.h is not included Lisp_Object is not defined (this can
152 happen when this files is used outside the src directory).
153 Use GCPRO1 to determine if lisp.h was included. */
154 #ifdef GCPRO1
155 /* defined in editfns.c*/
156 extern Lisp_Object make_time (time_t);
157 extern int lisp_time_argument (Lisp_Object, time_t *, int *);
158 #endif
159
160 /* Compare times T1 and T2. Value is 0 if T1 and T2 are the same.
161 Value is < 0 if T1 is less than T2. Value is > 0 otherwise. (Cast
162 to long is for those platforms where time_t is an unsigned
163 type, and where otherwise T1 will always be grater than T2.) */
164
165 #define EMACS_TIME_CMP(T1, T2) \
166 ((long)EMACS_SECS (T1) - (long)EMACS_SECS (T2) \
167 + (EMACS_SECS (T1) == EMACS_SECS (T2) \
168 ? EMACS_USECS (T1) - EMACS_USECS (T2) \
169 : 0))
170
171 /* Compare times T1 and T2 for equality, inequality etc. */
172
173 #define EMACS_TIME_EQ(T1, T2) (EMACS_TIME_CMP (T1, T2) == 0)
174 #define EMACS_TIME_NE(T1, T2) (EMACS_TIME_CMP (T1, T2) != 0)
175 #define EMACS_TIME_GT(T1, T2) (EMACS_TIME_CMP (T1, T2) > 0)
176 #define EMACS_TIME_GE(T1, T2) (EMACS_TIME_CMP (T1, T2) >= 0)
177 #define EMACS_TIME_LT(T1, T2) (EMACS_TIME_CMP (T1, T2) < 0)
178 #define EMACS_TIME_LE(T1, T2) (EMACS_TIME_CMP (T1, T2) <= 0)
179
180 #endif /* EMACS_SYSTIME_H */