src/timezone/pgtz.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * pgtz.h
   4  *        Timezone Library Integration Functions
   5  *
   6  * Note: this file contains only definitions that are private to the
   7  * timezone library.  Public definitions are in pgtime.h.
   8  *
   9  * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
  10  *
  11  * IDENTIFICATION
  12  *        src/timezone/pgtz.h
  13  *
  14  *-------------------------------------------------------------------------
  15  */
  16 #ifndef _PGTZ_H
  17 #define _PGTZ_H
  18
  19 #include "pgtime.h"
  20 #include "tzfile.h"
  21
  22
  23 #define SMALLEST(a, b)  (((a) < (b)) ? (a) : (b))
  24 #define BIGGEST(a, b)   (((a) > (b)) ? (a) : (b))
  25
  26 struct ttinfo
  27 {                                                               /* time type information */
  28         int32           tt_utoff;               /* UT offset in seconds */
  29         bool            tt_isdst;               /* used to set tm_isdst */
  30         int                     tt_desigidx;    /* abbreviation list index */
  31         bool            tt_ttisstd;             /* transition is std time */
  32         bool            tt_ttisut;              /* transition is UT */
  33 };
  34
  35 struct lsinfo
  36 {                                                               /* leap second information */
  37         pg_time_t       ls_trans;               /* transition time */
  38         int64           ls_corr;                /* correction to apply */
  39 };
  40
  41 struct state
  42 {
  43         int                     leapcnt;
  44         int                     timecnt;
  45         int                     typecnt;
  46         int                     charcnt;
  47         bool            goback;
  48         bool            goahead;
  49         pg_time_t       ats[TZ_MAX_TIMES];
  50         unsigned char types[TZ_MAX_TIMES];
  51         struct ttinfo ttis[TZ_MAX_TYPES];
  52         char            chars[BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, 4 /* sizeof gmt */ ),
  53                                                           (2 * (TZ_STRLEN_MAX + 1)))];
  54         struct lsinfo lsis[TZ_MAX_LEAPS];
  55
  56         /*
  57          * The time type to use for early times or if no transitions. It is always
  58          * zero for recent tzdb releases. It might be nonzero for data from tzdb
  59          * 2018e or earlier.
  60          */
  61         int                     defaulttype;
  62 };
  63
  64
  65 struct pg_tz
  66 {
  67         /* TZname contains the canonically-cased name of the timezone */
  68         char            TZname[TZ_STRLEN_MAX + 1];
  69         struct state state;
  70 };
  71
  72
  73 /* in pgtz.c */
  74 extern int      pg_open_tzfile(const char *name, char *canonname);
  75
  76 /* in localtime.c */
  77 extern int      tzload(const char *name, char *canonname, struct state *sp,
  78                                    bool doextend);
  79 extern bool tzparse(const char *name, struct state *sp, bool lastditch);
  80
  81 #endif                                                  /* _PGTZ_H */