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1 /*-------------------------------------------------------------------------
2  *
3  * timestamp.h
4  *        Definitions for the SQL92 "timestamp" and "interval" types.
5  *
6  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  * $PostgreSQL: pgsql/src/include/utils/timestamp.h,v 1.49 2005/07/21 04:48:42 momjian Exp $
10  *
11  *-------------------------------------------------------------------------
12  */
13 #ifndef TIMESTAMP_H
14 #define TIMESTAMP_H
15
16 #include <math.h>
17 #include <limits.h>
18 #include <float.h>
19
20 #include "fmgr.h"
21 #include "pgtime.h"
22 #ifdef HAVE_INT64_TIMESTAMP
23 #include "utils/int8.h"
24 #endif
25
26 /*
27  * Timestamp represents absolute time.
28  * Interval represents delta time. Keep track of months (and years), days,
29  *      and time separately since the elapsed time spanned is unknown until
30  *      instantiated relative to an absolute time.
31  *
32  * Note that Postgres uses "time interval" to mean a bounded interval,
33  * consisting of a beginning and ending time, not a time span - thomas 97/03/20
34  */
35
36 #ifdef HAVE_INT64_TIMESTAMP
37 typedef int64 Timestamp;
38 typedef int64 TimestampTz;
39
40 #else
41 typedef double Timestamp;
42 typedef double TimestampTz;
43 #endif
44
45 typedef struct
46 {
47 #ifdef HAVE_INT64_TIMESTAMP
48         int64           time;                   /* all time units other than days, 
49                                                                  * months and years */
50 #else
51         double          time;                   /* all time units other than days,
52                                                                  * months and years */
53 #endif
54         int32           day;                /* days, after time for alignment */
55         int32           month;                  /* months and years, after time for
56                                                                  * alignment */
57 } Interval;
58
59
60 #define MAX_TIMESTAMP_PRECISION 6
61 #define MAX_INTERVAL_PRECISION 6
62
63 /* in both timestamp.h and ecpg/dt.h */
64 #define DAYS_PER_YEAR   365.25  /* assumes leap year every four years */
65 #define MONTHS_PER_YEAR 12
66 #define DAYS_PER_MONTH  30              /* assumes exactly 30 days per month */
67 #define HOURS_PER_DAY   24              /* assume no daylight savings time changes */
68
69 #define SECS_PER_DAY    86400   /* assumes no leap second */
70 #define SECS_PER_HOUR   3600
71 #define SECS_PER_MINUTE 60
72
73 #ifdef HAVE_INT64_TIMESTAMP
74 #define USECS_PER_DAY   INT64CONST(86400000000)
75 #define USECS_PER_HOUR  INT64CONST(3600000000)
76 #define USECS_PER_MINUTE INT64CONST(60000000)
77 #define USECS_PER_SEC   INT64CONST(1000000)
78 #endif
79
80 /*
81  * Macros for fmgr-callable functions.
82  *
83  * For Timestamp, we make use of the same support routines as for int64
84  * or float8.  Therefore Timestamp is pass-by-reference if and only if
85  * int64 or float8 is!
86  */
87 #ifdef HAVE_INT64_TIMESTAMP
88
89 #define DatumGetTimestamp(X)  ((Timestamp) DatumGetInt64(X))
90 #define DatumGetTimestampTz(X)  ((TimestampTz) DatumGetInt64(X))
91 #define DatumGetIntervalP(X)  ((Interval *) DatumGetPointer(X))
92
93 #define TimestampGetDatum(X) Int64GetDatum(X)
94 #define TimestampTzGetDatum(X) Int64GetDatum(X)
95 #define IntervalPGetDatum(X) PointerGetDatum(X)
96
97 #define PG_GETARG_TIMESTAMP(n) PG_GETARG_INT64(n)
98 #define PG_GETARG_TIMESTAMPTZ(n) PG_GETARG_INT64(n)
99 #define PG_GETARG_INTERVAL_P(n) DatumGetIntervalP(PG_GETARG_DATUM(n))
100
101 #define PG_RETURN_TIMESTAMP(x) PG_RETURN_INT64(x)
102 #define PG_RETURN_TIMESTAMPTZ(x) PG_RETURN_INT64(x)
103 #define PG_RETURN_INTERVAL_P(x) return IntervalPGetDatum(x)
104
105 #define DT_NOBEGIN              (-INT64CONST(0x7fffffffffffffff) - 1)
106 #define DT_NOEND                (INT64CONST(0x7fffffffffffffff))
107
108 #else
109
110 #define DatumGetTimestamp(X)  ((Timestamp) DatumGetFloat8(X))
111 #define DatumGetTimestampTz(X)  ((TimestampTz) DatumGetFloat8(X))
112 #define DatumGetIntervalP(X)  ((Interval *) DatumGetPointer(X))
113
114 #define TimestampGetDatum(X) Float8GetDatum(X)
115 #define TimestampTzGetDatum(X) Float8GetDatum(X)
116 #define IntervalPGetDatum(X) PointerGetDatum(X)
117
118 #define PG_GETARG_TIMESTAMP(n) DatumGetTimestamp(PG_GETARG_DATUM(n))
119 #define PG_GETARG_TIMESTAMPTZ(n) DatumGetTimestampTz(PG_GETARG_DATUM(n))
120 #define PG_GETARG_INTERVAL_P(n) DatumGetIntervalP(PG_GETARG_DATUM(n))
121
122 #define PG_RETURN_TIMESTAMP(x) return TimestampGetDatum(x)
123 #define PG_RETURN_TIMESTAMPTZ(x) return TimestampTzGetDatum(x)
124 #define PG_RETURN_INTERVAL_P(x) return IntervalPGetDatum(x)
125
126 #ifdef HUGE_VAL
127 #define DT_NOBEGIN              (-HUGE_VAL)
128 #define DT_NOEND                (HUGE_VAL)
129 #else
130 #define DT_NOBEGIN              (-DBL_MAX)
131 #define DT_NOEND                (DBL_MAX)
132 #endif
133 #endif   /* HAVE_INT64_TIMESTAMP */
134
135
136 #define TIMESTAMP_NOBEGIN(j)    do {(j) = DT_NOBEGIN;} while (0)
137 #define TIMESTAMP_IS_NOBEGIN(j) ((j) == DT_NOBEGIN)
138
139 #define TIMESTAMP_NOEND(j)              do {(j) = DT_NOEND;} while (0)
140 #define TIMESTAMP_IS_NOEND(j)   ((j) == DT_NOEND)
141
142 #define TIMESTAMP_NOT_FINITE(j) (TIMESTAMP_IS_NOBEGIN(j) || TIMESTAMP_IS_NOEND(j))
143
144 #ifdef HAVE_INT64_TIMESTAMP
145
146 typedef int32 fsec_t;
147
148 #else
149
150 typedef double fsec_t;
151
152 #define TIME_PREC_INV 1000000.0
153 #define JROUND(j) (rint(((double) (j))*TIME_PREC_INV)/TIME_PREC_INV)
154 #endif
155
156 #define TIMESTAMP_MASK(b) (1 << (b))
157 #define INTERVAL_MASK(b) (1 << (b))
158
159 /* Macros to handle packing and unpacking the typmod field for intervals */
160 #define INTERVAL_FULL_RANGE (0x7FFF)
161 #define INTERVAL_RANGE_MASK (0x7FFF)
162 #define INTERVAL_FULL_PRECISION (0xFFFF)
163 #define INTERVAL_PRECISION_MASK (0xFFFF)
164 #define INTERVAL_TYPMOD(p,r) ((((r) & INTERVAL_RANGE_MASK) << 16) | ((p) & INTERVAL_PRECISION_MASK))
165 #define INTERVAL_PRECISION(t) ((t) & INTERVAL_PRECISION_MASK)
166 #define INTERVAL_RANGE(t) (((t) >> 16) & INTERVAL_RANGE_MASK)
167
168
169 /* Set at postmaster start */
170 extern TimestampTz PgStartTime;
171
172
173 /*
174  * timestamp.c prototypes
175  */
176
177 extern Datum timestamp_in(PG_FUNCTION_ARGS);
178 extern Datum timestamp_out(PG_FUNCTION_ARGS);
179 extern Datum timestamp_recv(PG_FUNCTION_ARGS);
180 extern Datum timestamp_send(PG_FUNCTION_ARGS);
181 extern Datum timestamp_scale(PG_FUNCTION_ARGS);
182 extern Datum timestamp_eq(PG_FUNCTION_ARGS);
183 extern Datum timestamp_ne(PG_FUNCTION_ARGS);
184 extern Datum timestamp_lt(PG_FUNCTION_ARGS);
185 extern Datum timestamp_le(PG_FUNCTION_ARGS);
186 extern Datum timestamp_ge(PG_FUNCTION_ARGS);
187 extern Datum timestamp_gt(PG_FUNCTION_ARGS);
188 extern Datum timestamp_finite(PG_FUNCTION_ARGS);
189 extern Datum timestamp_cmp(PG_FUNCTION_ARGS);
190 extern Datum timestamp_smaller(PG_FUNCTION_ARGS);
191 extern Datum timestamp_larger(PG_FUNCTION_ARGS);
192
193 extern Datum timestamp_eq_timestamptz(PG_FUNCTION_ARGS);
194 extern Datum timestamp_ne_timestamptz(PG_FUNCTION_ARGS);
195 extern Datum timestamp_lt_timestamptz(PG_FUNCTION_ARGS);
196 extern Datum timestamp_le_timestamptz(PG_FUNCTION_ARGS);
197 extern Datum timestamp_gt_timestamptz(PG_FUNCTION_ARGS);
198 extern Datum timestamp_ge_timestamptz(PG_FUNCTION_ARGS);
199 extern Datum timestamp_cmp_timestamptz(PG_FUNCTION_ARGS);
200
201 extern Datum timestamptz_eq_timestamp(PG_FUNCTION_ARGS);
202 extern Datum timestamptz_ne_timestamp(PG_FUNCTION_ARGS);
203 extern Datum timestamptz_lt_timestamp(PG_FUNCTION_ARGS);
204 extern Datum timestamptz_le_timestamp(PG_FUNCTION_ARGS);
205 extern Datum timestamptz_gt_timestamp(PG_FUNCTION_ARGS);
206 extern Datum timestamptz_ge_timestamp(PG_FUNCTION_ARGS);
207 extern Datum timestamptz_cmp_timestamp(PG_FUNCTION_ARGS);
208
209 extern Datum interval_in(PG_FUNCTION_ARGS);
210 extern Datum interval_out(PG_FUNCTION_ARGS);
211 extern Datum interval_recv(PG_FUNCTION_ARGS);
212 extern Datum interval_send(PG_FUNCTION_ARGS);
213 extern Datum interval_scale(PG_FUNCTION_ARGS);
214 extern Datum interval_eq(PG_FUNCTION_ARGS);
215 extern Datum interval_ne(PG_FUNCTION_ARGS);
216 extern Datum interval_lt(PG_FUNCTION_ARGS);
217 extern Datum interval_le(PG_FUNCTION_ARGS);
218 extern Datum interval_ge(PG_FUNCTION_ARGS);
219 extern Datum interval_gt(PG_FUNCTION_ARGS);
220 extern Datum interval_finite(PG_FUNCTION_ARGS);
221 extern Datum interval_cmp(PG_FUNCTION_ARGS);
222 extern Datum interval_hash(PG_FUNCTION_ARGS);
223 extern Datum interval_smaller(PG_FUNCTION_ARGS);
224 extern Datum interval_larger(PG_FUNCTION_ARGS);
225 extern Datum interval_justify_hours(PG_FUNCTION_ARGS);
226 extern Datum interval_justify_days(PG_FUNCTION_ARGS);
227
228 extern Datum timestamp_text(PG_FUNCTION_ARGS);
229 extern Datum text_timestamp(PG_FUNCTION_ARGS);
230 extern Datum interval_text(PG_FUNCTION_ARGS);
231 extern Datum text_interval(PG_FUNCTION_ARGS);
232 extern Datum timestamp_trunc(PG_FUNCTION_ARGS);
233 extern Datum interval_trunc(PG_FUNCTION_ARGS);
234 extern Datum timestamp_part(PG_FUNCTION_ARGS);
235 extern Datum interval_part(PG_FUNCTION_ARGS);
236 extern Datum timestamp_zone(PG_FUNCTION_ARGS);
237 extern Datum timestamp_izone(PG_FUNCTION_ARGS);
238 extern Datum timestamp_timestamptz(PG_FUNCTION_ARGS);
239
240 extern Datum timestamptz_in(PG_FUNCTION_ARGS);
241 extern Datum timestamptz_out(PG_FUNCTION_ARGS);
242 extern Datum timestamptz_recv(PG_FUNCTION_ARGS);
243 extern Datum timestamptz_send(PG_FUNCTION_ARGS);
244 extern Datum timestamptz_scale(PG_FUNCTION_ARGS);
245 extern Datum timestamptz_timestamp(PG_FUNCTION_ARGS);
246 extern Datum timestamptz_zone(PG_FUNCTION_ARGS);
247 extern Datum timestamptz_izone(PG_FUNCTION_ARGS);
248 extern Datum timestamptz_timestamptz(PG_FUNCTION_ARGS);
249
250 extern Datum interval_um(PG_FUNCTION_ARGS);
251 extern Datum interval_pl(PG_FUNCTION_ARGS);
252 extern Datum interval_mi(PG_FUNCTION_ARGS);
253 extern Datum interval_mul(PG_FUNCTION_ARGS);
254 extern Datum mul_d_interval(PG_FUNCTION_ARGS);
255 extern Datum interval_div(PG_FUNCTION_ARGS);
256 extern Datum interval_accum(PG_FUNCTION_ARGS);
257 extern Datum interval_avg(PG_FUNCTION_ARGS);
258
259 extern Datum timestamp_mi(PG_FUNCTION_ARGS);
260 extern Datum timestamp_pl_interval(PG_FUNCTION_ARGS);
261 extern Datum timestamp_mi_interval(PG_FUNCTION_ARGS);
262 extern Datum timestamp_age(PG_FUNCTION_ARGS);
263 extern Datum overlaps_timestamp(PG_FUNCTION_ARGS);
264
265 extern Datum timestamptz_text(PG_FUNCTION_ARGS);
266 extern Datum text_timestamptz(PG_FUNCTION_ARGS);
267 extern Datum timestamptz_pl_interval(PG_FUNCTION_ARGS);
268 extern Datum timestamptz_mi_interval(PG_FUNCTION_ARGS);
269 extern Datum timestamptz_age(PG_FUNCTION_ARGS);
270 extern Datum timestamptz_trunc(PG_FUNCTION_ARGS);
271 extern Datum timestamptz_part(PG_FUNCTION_ARGS);
272
273 extern Datum now(PG_FUNCTION_ARGS);
274
275 extern Datum pgsql_postmaster_start_time(PG_FUNCTION_ARGS);
276
277 /* Internal routines (not fmgr-callable) */
278
279 extern TimestampTz GetCurrentTimestamp(void);
280
281 extern int      tm2timestamp(struct pg_tm *tm, fsec_t fsec, int *tzp, Timestamp *dt);
282 extern int timestamp2tm(Timestamp dt, int *tzp, struct pg_tm *tm,
283                          fsec_t *fsec, char **tzn, pg_tz *attimezone);
284 extern void dt2time(Timestamp dt, int *hour, int *min, int *sec, fsec_t *fsec);
285
286 extern int      interval2tm(Interval span, struct pg_tm *tm, fsec_t *fsec);
287 extern int      tm2interval(struct pg_tm *tm, fsec_t fsec, Interval *span);
288
289 extern Timestamp SetEpochTimestamp(void);
290 extern void GetEpochTime(struct pg_tm *tm);
291
292 extern int      timestamp_cmp_internal(Timestamp dt1, Timestamp dt2);
293
294 /* timestamp comparison works for timestamptz also */
295 #define timestamptz_cmp_internal(dt1,dt2)       timestamp_cmp_internal(dt1, dt2)
296
297 extern void isoweek2date(int woy, int *year, int *mon, int *mday);
298 extern int      date2isoweek(int year, int mon, int mday);
299 extern int      date2isoyear(int year, int mon, int mday);
300
301 #endif   /* TIMESTAMP_H */