src/include/utils/timestamp.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * timestamp.h
   4  *        Definitions for the SQL92 "timestamp" and "interval" types.
   5  *
   6  * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  * $PostgreSQL$
  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  *
  29  * Interval represents delta time. Keep track of months (and years), days,
  30  * and hours/minutes/seconds separately since the elapsed time spanned is
  31  * unknown until instantiated relative to an absolute time.
  32  *
  33  * Note that Postgres uses "time interval" to mean a bounded interval,
  34  * consisting of a beginning and ending time, not a time span - thomas 97/03/20
  35  *
  36  * We have two implementations, one that uses int64 values with units of
  37  * microseconds, and one that uses double values with units of seconds.
  38  *
  39  * TimeOffset and fsec_t are convenience typedefs for temporary variables
  40  * that are of different types in the two cases.  Do not use fsec_t in values
  41  * stored on-disk, since it is not the same size in both implementations.
  42  */
  43
  44 #ifdef HAVE_INT64_TIMESTAMP
  45
  46 typedef int64 Timestamp;
  47 typedef int64 TimestampTz;
  48 typedef int64 TimeOffset;
  49 typedef int32 fsec_t;                   /* fractional seconds (in microseconds) */
  50 #else
  51
  52 typedef double Timestamp;
  53 typedef double TimestampTz;
  54 typedef double TimeOffset;
  55 typedef double fsec_t;                  /* fractional seconds (in seconds) */
  56 #endif
  57
  58 typedef struct
  59 {
  60         TimeOffset      time;                   /* all time units other than days, months and
  61                                                                  * years */
  62         int32           day;                    /* days, after time for alignment */
  63         int32           month;                  /* months and years, after time for alignment */
  64 } Interval;
  65
  66
  67 #define MAX_TIMESTAMP_PRECISION 6
  68 #define MAX_INTERVAL_PRECISION 6
  69
  70 /* in both timestamp.h and ecpg/dt.h */
  71 #define DAYS_PER_YEAR   365.25  /* assumes leap year every four years */
  72 #define MONTHS_PER_YEAR 12
  73 /*
  74  *      DAYS_PER_MONTH is very imprecise.  The more accurate value is
  75  *      365.2425/12 = 30.436875, or '30 days 10:29:06'.  Right now we only
  76  *      return an integral number of days, but someday perhaps we should
  77  *      also return a 'time' value to be used as well.  ISO 8601 suggests
  78  *      30 days.
  79  */
  80 #define DAYS_PER_MONTH  30              /* assumes exactly 30 days per month */
  81 #define HOURS_PER_DAY   24              /* assume no daylight savings time changes */
  82
  83 /*
  84  *      This doesn't adjust for uneven daylight savings time intervals or leap
  85  *      seconds, and it crudely estimates leap years.  A more accurate value
  86  *      for days per years is 365.2422.
  87  */
  88 #define SECS_PER_YEAR   (36525 * 864)   /* avoid floating-point computation */
  89 #define SECS_PER_DAY    86400
  90 #define SECS_PER_HOUR   3600
  91 #define SECS_PER_MINUTE 60
  92 #define MINS_PER_HOUR   60
  93
  94 #ifdef HAVE_INT64_TIMESTAMP
  95 #define USECS_PER_DAY   INT64CONST(86400000000)
  96 #define USECS_PER_HOUR  INT64CONST(3600000000)
  97 #define USECS_PER_MINUTE INT64CONST(60000000)
  98 #define USECS_PER_SEC   INT64CONST(1000000)
  99 #endif
 100
 101 /*
 102  * Macros for fmgr-callable functions.
 103  *
 104  * For Timestamp, we make use of the same support routines as for int64
 105  * or float8.  Therefore Timestamp is pass-by-reference if and only if
 106  * int64 or float8 is!
 107  */
 108 #ifdef HAVE_INT64_TIMESTAMP
 109
 110 #define DatumGetTimestamp(X)  ((Timestamp) DatumGetInt64(X))
 111 #define DatumGetTimestampTz(X)  ((TimestampTz) DatumGetInt64(X))
 112 #define DatumGetIntervalP(X)  ((Interval *) DatumGetPointer(X))
 113
 114 #define TimestampGetDatum(X) Int64GetDatum(X)
 115 #define TimestampTzGetDatum(X) Int64GetDatum(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 #define DT_NOBEGIN              (-INT64CONST(0x7fffffffffffffff) - 1)
 127 #define DT_NOEND                (INT64CONST(0x7fffffffffffffff))
 128 #else                                                   /* !HAVE_INT64_TIMESTAMP */
 129
 130 #define DatumGetTimestamp(X)  ((Timestamp) DatumGetFloat8(X))
 131 #define DatumGetTimestampTz(X)  ((TimestampTz) DatumGetFloat8(X))
 132 #define DatumGetIntervalP(X)  ((Interval *) DatumGetPointer(X))
 133
 134 #define TimestampGetDatum(X) Float8GetDatum(X)
 135 #define TimestampTzGetDatum(X) Float8GetDatum(X)
 136 #define IntervalPGetDatum(X) PointerGetDatum(X)
 137
 138 #define PG_GETARG_TIMESTAMP(n) DatumGetTimestamp(PG_GETARG_DATUM(n))
 139 #define PG_GETARG_TIMESTAMPTZ(n) DatumGetTimestampTz(PG_GETARG_DATUM(n))
 140 #define PG_GETARG_INTERVAL_P(n) DatumGetIntervalP(PG_GETARG_DATUM(n))
 141
 142 #define PG_RETURN_TIMESTAMP(x) return TimestampGetDatum(x)
 143 #define PG_RETURN_TIMESTAMPTZ(x) return TimestampTzGetDatum(x)
 144 #define PG_RETURN_INTERVAL_P(x) return IntervalPGetDatum(x)
 145
 146 #ifdef HUGE_VAL
 147 #define DT_NOBEGIN              (-HUGE_VAL)
 148 #define DT_NOEND                (HUGE_VAL)
 149 #else
 150 #define DT_NOBEGIN              (-DBL_MAX)
 151 #define DT_NOEND                (DBL_MAX)
 152 #endif
 153 #endif   /* HAVE_INT64_TIMESTAMP */
 154
 155
 156 #define TIMESTAMP_NOBEGIN(j)    \
 157         do {(j) = DT_NOBEGIN;} while (0)
 158 #define TIMESTAMP_IS_NOBEGIN(j) ((j) == DT_NOBEGIN)
 159
 160 #define TIMESTAMP_NOEND(j)              \
 161         do {(j) = DT_NOEND;} while (0)
 162 #define TIMESTAMP_IS_NOEND(j)   ((j) == DT_NOEND)
 163
 164 #define TIMESTAMP_NOT_FINITE(j) (TIMESTAMP_IS_NOBEGIN(j) || TIMESTAMP_IS_NOEND(j))
 165
 166 /*
 167  *      Round off to MAX_TIMESTAMP_PRECISION decimal places.
 168  *      Note: this is also used for rounding off intervals.
 169  */
 170 #define TS_PREC_INV 1000000.0
 171 #define TSROUND(j) (rint(((double) (j)) * TS_PREC_INV) / TS_PREC_INV)
 172
 173 #define TIMESTAMP_MASK(b) (1 << (b))
 174 #define INTERVAL_MASK(b) (1 << (b))
 175
 176 /* Macros to handle packing and unpacking the typmod field for intervals */
 177 #define INTERVAL_FULL_RANGE (0x7FFF)
 178 #define INTERVAL_RANGE_MASK (0x7FFF)
 179 #define INTERVAL_FULL_PRECISION (0xFFFF)
 180 #define INTERVAL_PRECISION_MASK (0xFFFF)
 181 #define INTERVAL_TYPMOD(p,r) ((((r) & INTERVAL_RANGE_MASK) << 16) | ((p) & INTERVAL_PRECISION_MASK))
 182 #define INTERVAL_PRECISION(t) ((t) & INTERVAL_PRECISION_MASK)
 183 #define INTERVAL_RANGE(t) (((t) >> 16) & INTERVAL_RANGE_MASK)
 184
 185 #ifdef HAVE_INT64_TIMESTAMP
 186 #define TimestampTzPlusMilliseconds(tz,ms) ((tz) + ((ms) * (int64) 1000))
 187 #else
 188 #define TimestampTzPlusMilliseconds(tz,ms) ((tz) + ((ms) / 1000.0))
 189 #endif
 190
 191
 192 /* Set at postmaster start */
 193 extern TimestampTz PgStartTime;
 194
 195 /* Set at configuration reload */
 196 extern TimestampTz PgReloadTime;
 197
 198
 199 /*
 200  * timestamp.c prototypes
 201  */
 202
 203 extern Datum timestamp_in(PG_FUNCTION_ARGS);
 204 extern Datum timestamp_out(PG_FUNCTION_ARGS);
 205 extern Datum timestamp_recv(PG_FUNCTION_ARGS);
 206 extern Datum timestamp_send(PG_FUNCTION_ARGS);
 207 extern Datum timestamptypmodin(PG_FUNCTION_ARGS);
 208 extern Datum timestamptypmodout(PG_FUNCTION_ARGS);
 209 extern Datum timestamp_scale(PG_FUNCTION_ARGS);
 210 extern Datum timestamp_eq(PG_FUNCTION_ARGS);
 211 extern Datum timestamp_ne(PG_FUNCTION_ARGS);
 212 extern Datum timestamp_lt(PG_FUNCTION_ARGS);
 213 extern Datum timestamp_le(PG_FUNCTION_ARGS);
 214 extern Datum timestamp_ge(PG_FUNCTION_ARGS);
 215 extern Datum timestamp_gt(PG_FUNCTION_ARGS);
 216 extern Datum timestamp_finite(PG_FUNCTION_ARGS);
 217 extern Datum timestamp_cmp(PG_FUNCTION_ARGS);
 218 extern Datum timestamp_hash(PG_FUNCTION_ARGS);
 219 extern Datum timestamp_smaller(PG_FUNCTION_ARGS);
 220 extern Datum timestamp_larger(PG_FUNCTION_ARGS);
 221
 222 extern Datum timestamp_eq_timestamptz(PG_FUNCTION_ARGS);
 223 extern Datum timestamp_ne_timestamptz(PG_FUNCTION_ARGS);
 224 extern Datum timestamp_lt_timestamptz(PG_FUNCTION_ARGS);
 225 extern Datum timestamp_le_timestamptz(PG_FUNCTION_ARGS);
 226 extern Datum timestamp_gt_timestamptz(PG_FUNCTION_ARGS);
 227 extern Datum timestamp_ge_timestamptz(PG_FUNCTION_ARGS);
 228 extern Datum timestamp_cmp_timestamptz(PG_FUNCTION_ARGS);
 229
 230 extern Datum timestamptz_eq_timestamp(PG_FUNCTION_ARGS);
 231 extern Datum timestamptz_ne_timestamp(PG_FUNCTION_ARGS);
 232 extern Datum timestamptz_lt_timestamp(PG_FUNCTION_ARGS);
 233 extern Datum timestamptz_le_timestamp(PG_FUNCTION_ARGS);
 234 extern Datum timestamptz_gt_timestamp(PG_FUNCTION_ARGS);
 235 extern Datum timestamptz_ge_timestamp(PG_FUNCTION_ARGS);
 236 extern Datum timestamptz_cmp_timestamp(PG_FUNCTION_ARGS);
 237
 238 extern Datum interval_in(PG_FUNCTION_ARGS);
 239 extern Datum interval_out(PG_FUNCTION_ARGS);
 240 extern Datum interval_recv(PG_FUNCTION_ARGS);
 241 extern Datum interval_send(PG_FUNCTION_ARGS);
 242 extern Datum intervaltypmodin(PG_FUNCTION_ARGS);
 243 extern Datum intervaltypmodout(PG_FUNCTION_ARGS);
 244 extern Datum interval_scale(PG_FUNCTION_ARGS);
 245 extern Datum interval_eq(PG_FUNCTION_ARGS);
 246 extern Datum interval_ne(PG_FUNCTION_ARGS);
 247 extern Datum interval_lt(PG_FUNCTION_ARGS);
 248 extern Datum interval_le(PG_FUNCTION_ARGS);
 249 extern Datum interval_ge(PG_FUNCTION_ARGS);
 250 extern Datum interval_gt(PG_FUNCTION_ARGS);
 251 extern Datum interval_finite(PG_FUNCTION_ARGS);
 252 extern Datum interval_cmp(PG_FUNCTION_ARGS);
 253 extern Datum interval_hash(PG_FUNCTION_ARGS);
 254 extern Datum interval_smaller(PG_FUNCTION_ARGS);
 255 extern Datum interval_larger(PG_FUNCTION_ARGS);
 256 extern Datum interval_justify_interval(PG_FUNCTION_ARGS);
 257 extern Datum interval_justify_hours(PG_FUNCTION_ARGS);
 258 extern Datum interval_justify_days(PG_FUNCTION_ARGS);
 259
 260 extern Datum timestamp_trunc(PG_FUNCTION_ARGS);
 261 extern Datum interval_trunc(PG_FUNCTION_ARGS);
 262 extern Datum timestamp_part(PG_FUNCTION_ARGS);
 263 extern Datum interval_part(PG_FUNCTION_ARGS);
 264 extern Datum timestamp_zone(PG_FUNCTION_ARGS);
 265 extern Datum timestamp_izone(PG_FUNCTION_ARGS);
 266 extern Datum timestamp_timestamptz(PG_FUNCTION_ARGS);
 267
 268 extern Datum timestamptz_in(PG_FUNCTION_ARGS);
 269 extern Datum timestamptz_out(PG_FUNCTION_ARGS);
 270 extern Datum timestamptz_recv(PG_FUNCTION_ARGS);
 271 extern Datum timestamptz_send(PG_FUNCTION_ARGS);
 272 extern Datum timestamptztypmodin(PG_FUNCTION_ARGS);
 273 extern Datum timestamptztypmodout(PG_FUNCTION_ARGS);
 274 extern Datum timestamptz_scale(PG_FUNCTION_ARGS);
 275 extern Datum timestamptz_timestamp(PG_FUNCTION_ARGS);
 276 extern Datum timestamptz_zone(PG_FUNCTION_ARGS);
 277 extern Datum timestamptz_izone(PG_FUNCTION_ARGS);
 278 extern Datum timestamptz_timestamptz(PG_FUNCTION_ARGS);
 279
 280 extern Datum interval_um(PG_FUNCTION_ARGS);
 281 extern Datum interval_pl(PG_FUNCTION_ARGS);
 282 extern Datum interval_mi(PG_FUNCTION_ARGS);
 283 extern Datum interval_mul(PG_FUNCTION_ARGS);
 284 extern Datum mul_d_interval(PG_FUNCTION_ARGS);
 285 extern Datum interval_div(PG_FUNCTION_ARGS);
 286 extern Datum interval_accum(PG_FUNCTION_ARGS);
 287 extern Datum interval_avg(PG_FUNCTION_ARGS);
 288
 289 extern Datum timestamp_mi(PG_FUNCTION_ARGS);
 290 extern Datum timestamp_pl_interval(PG_FUNCTION_ARGS);
 291 extern Datum timestamp_mi_interval(PG_FUNCTION_ARGS);
 292 extern Datum timestamp_age(PG_FUNCTION_ARGS);
 293 extern Datum overlaps_timestamp(PG_FUNCTION_ARGS);
 294
 295 extern Datum timestamptz_pl_interval(PG_FUNCTION_ARGS);
 296 extern Datum timestamptz_mi_interval(PG_FUNCTION_ARGS);
 297 extern Datum timestamptz_age(PG_FUNCTION_ARGS);
 298 extern Datum timestamptz_trunc(PG_FUNCTION_ARGS);
 299 extern Datum timestamptz_part(PG_FUNCTION_ARGS);
 300
 301 extern Datum now(PG_FUNCTION_ARGS);
 302 extern Datum statement_timestamp(PG_FUNCTION_ARGS);
 303 extern Datum clock_timestamp(PG_FUNCTION_ARGS);
 304
 305 extern Datum pg_postmaster_start_time(PG_FUNCTION_ARGS);
 306 extern Datum pg_conf_load_time(PG_FUNCTION_ARGS);
 307
 308 extern Datum generate_series_timestamp(PG_FUNCTION_ARGS);
 309 extern Datum generate_series_timestamptz(PG_FUNCTION_ARGS);
 310
 311 /* Internal routines (not fmgr-callable) */
 312
 313 extern TimestampTz GetCurrentTimestamp(void);
 314
 315 extern void TimestampDifference(TimestampTz start_time, TimestampTz stop_time,
 316                                         long *secs, int *microsecs);
 317 extern bool TimestampDifferenceExceeds(TimestampTz start_time,
 318                                                    TimestampTz stop_time,
 319                                                    int msec);
 320
 321 extern TimestampTz time_t_to_timestamptz(pg_time_t tm);
 322 extern pg_time_t timestamptz_to_time_t(TimestampTz t);
 323
 324 extern const char *timestamptz_to_str(TimestampTz t);
 325
 326 extern int      tm2timestamp(struct pg_tm * tm, fsec_t fsec, int *tzp, Timestamp *dt);
 327 extern int timestamp2tm(Timestamp dt, int *tzp, struct pg_tm * tm,
 328                          fsec_t *fsec, char **tzn, pg_tz *attimezone);
 329 extern void dt2time(Timestamp dt, int *hour, int *min, int *sec, fsec_t *fsec);
 330
 331 extern int      interval2tm(Interval span, struct pg_tm * tm, fsec_t *fsec);
 332 extern int      tm2interval(struct pg_tm * tm, fsec_t fsec, Interval *span);
 333
 334 extern Timestamp SetEpochTimestamp(void);
 335 extern void GetEpochTime(struct pg_tm * tm);
 336
 337 extern int      timestamp_cmp_internal(Timestamp dt1, Timestamp dt2);
 338
 339 /* timestamp comparison works for timestamptz also */
 340 #define timestamptz_cmp_internal(dt1,dt2)       timestamp_cmp_internal(dt1, dt2)
 341
 342 extern int      isoweek2j(int year, int week);
 343 extern void isoweek2date(int woy, int *year, int *mon, int *mday);
 344 extern void isoweekdate2date(int isoweek, int isowday, int *year, int *mon, int *mday);
 345 extern int      date2isoweek(int year, int mon, int mday);
 346 extern int      date2isoyear(int year, int mon, int mday);
 347 extern int      date2isoyearday(int year, int mon, int mday);
 348
 349 #endif   /* TIMESTAMP_H */