src/timezone/private.h

   1 /* Private header for tzdb code.  */
   2
   3 #ifndef PRIVATE_H
   4
   5 #define PRIVATE_H
   6
   7 /*
   8  * This file is in the public domain, so clarified as of
   9  * 1996-06-05 by Arthur David Olson.
  10  *
  11  * IDENTIFICATION
  12  *        src/timezone/private.h
  13  */
  14
  15 /*
  16  * This header is for use ONLY with the time conversion code.
  17  * There is no guarantee that it will remain unchanged,
  18  * or that it will remain at all.
  19  * Do NOT copy it to any system include directory.
  20  * Thank you!
  21  */
  22
  23 #include <limits.h>                             /* for CHAR_BIT et al. */
  24 #include <sys/wait.h>                   /* for WIFEXITED and WEXITSTATUS */
  25 #include <unistd.h>                             /* for F_OK and R_OK */
  26
  27 #include "pgtime.h"
  28
  29 /* This string was in the Factory zone through version 2016f.  */
  30 #define GRANDPARENTED   "Local time zone must be set--see zic manual page"
  31
  32 /*
  33  * IANA has a bunch of HAVE_FOO #defines here, but in PG we want pretty
  34  * much all of that to be done by PG's configure script.
  35  */
  36
  37 #ifndef ENOTSUP
  38 #define ENOTSUP EINVAL
  39 #endif
  40 #ifndef EOVERFLOW
  41 #define EOVERFLOW EINVAL
  42 #endif
  43
  44 /* Unlike <ctype.h>'s isdigit, this also works if c < 0 | c > UCHAR_MAX. */
  45 #define is_digit(c) ((unsigned)(c) - '0' <= 9)
  46
  47 /* PG doesn't currently rely on <inttypes.h>, so work around strtoimax() */
  48 #undef strtoimax
  49 #define strtoimax strtoll
  50
  51
  52 /*
  53  * Finally, some convenience items.
  54  */
  55
  56 #define TYPE_BIT(type)  (sizeof (type) * CHAR_BIT)
  57 #define TYPE_SIGNED(type) (((type) -1) < 0)
  58 #define TWOS_COMPLEMENT(t) ((t) ~ (t) 0 < 0)
  59
  60 /*
  61  * Max and min values of the integer type T, of which only the bottom
  62  * B bits are used, and where the highest-order used bit is considered
  63  * to be a sign bit if T is signed.
  64  */
  65 #define MAXVAL(t, b)                                            \
  66   ((t) (((t) 1 << ((b) - 1 - TYPE_SIGNED(t)))                   \
  67         - 1 + ((t) 1 << ((b) - 1 - TYPE_SIGNED(t)))))
  68 #define MINVAL(t, b)                                            \
  69   ((t) (TYPE_SIGNED(t) ? - TWOS_COMPLEMENT(t) - MAXVAL(t, b) : 0))
  70
  71 /* The extreme time values, assuming no padding.  */
  72 #define TIME_T_MIN MINVAL(pg_time_t, TYPE_BIT(pg_time_t))
  73 #define TIME_T_MAX MAXVAL(pg_time_t, TYPE_BIT(pg_time_t))
  74
  75 /*
  76  * 302 / 1000 is log10(2.0) rounded up.
  77  * Subtract one for the sign bit if the type is signed;
  78  * add one for integer division truncation;
  79  * add one more for a minus sign if the type is signed.
  80  */
  81 #define INT_STRLEN_MAXIMUM(type) \
  82         ((TYPE_BIT(type) - TYPE_SIGNED(type)) * 302 / 1000 + \
  83         1 + TYPE_SIGNED(type))
  84
  85 /*
  86  * INITIALIZE(x)
  87  */
  88 #define INITIALIZE(x)   ((x) = 0)
  89
  90 #undef _
  91 #define _(msgid) (msgid)
  92
  93 /* Handy macros that are independent of tzfile implementation.  */
  94
  95 #define YEARSPERREPEAT          400 /* years before a Gregorian repeat */
  96
  97 #define SECSPERMIN      60
  98 #define MINSPERHOUR 60
  99 #define HOURSPERDAY 24
 100 #define DAYSPERWEEK 7
 101 #define DAYSPERNYEAR    365
 102 #define DAYSPERLYEAR    366
 103 #define SECSPERHOUR (SECSPERMIN * MINSPERHOUR)
 104 #define SECSPERDAY      ((int32) SECSPERHOUR * HOURSPERDAY)
 105 #define MONSPERYEAR 12
 106
 107 #define TM_SUNDAY       0
 108 #define TM_MONDAY       1
 109 #define TM_TUESDAY      2
 110 #define TM_WEDNESDAY    3
 111 #define TM_THURSDAY 4
 112 #define TM_FRIDAY       5
 113 #define TM_SATURDAY 6
 114
 115 #define TM_JANUARY      0
 116 #define TM_FEBRUARY 1
 117 #define TM_MARCH        2
 118 #define TM_APRIL        3
 119 #define TM_MAY          4
 120 #define TM_JUNE         5
 121 #define TM_JULY         6
 122 #define TM_AUGUST       7
 123 #define TM_SEPTEMBER    8
 124 #define TM_OCTOBER      9
 125 #define TM_NOVEMBER 10
 126 #define TM_DECEMBER 11
 127
 128 #define TM_YEAR_BASE    1900
 129
 130 #define EPOCH_YEAR      1970
 131 #define EPOCH_WDAY      TM_THURSDAY
 132
 133 #define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
 134
 135 /*
 136  * Since everything in isleap is modulo 400 (or a factor of 400), we know that
 137  *      isleap(y) == isleap(y % 400)
 138  * and so
 139  *      isleap(a + b) == isleap((a + b) % 400)
 140  * or
 141  *      isleap(a + b) == isleap(a % 400 + b % 400)
 142  * This is true even if % means modulo rather than Fortran remainder
 143  * (which is allowed by C89 but not by C99 or later).
 144  * We use this to avoid addition overflow problems.
 145  */
 146
 147 #define isleap_sum(a, b)        isleap((a) % 400 + (b) % 400)
 148
 149
 150 /*
 151  * The Gregorian year averages 365.2425 days, which is 31556952 seconds.
 152  */
 153
 154 #define AVGSECSPERYEAR          31556952L
 155 #define SECSPERREPEAT \
 156   ((int64) YEARSPERREPEAT * (int64) AVGSECSPERYEAR)
 157 #define SECSPERREPEAT_BITS      34      /* ceil(log2(SECSPERREPEAT)) */
 158
 159 #endif                                                  /* !defined PRIVATE_H */