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Diffstat (limited to 'time/localtime.c')
| -rw-r--r-- | time/localtime.c | 1569 |
1 files changed, 1569 insertions, 0 deletions
diff --git a/time/localtime.c b/time/localtime.c new file mode 100644 index 000000000..1ae36fe9f --- /dev/null +++ b/time/localtime.c @@ -0,0 +1,1569 @@ +#ifndef lint +#ifndef NOID +static char elsieid[] = "@(#)localtime.c 7.26"; +#endif /* !defined NOID */ +#endif /* !defined lint */ + +/* +** Leap second handling from Bradley White (bww@k.gp.cs.cmu.edu). +** POSIX-style TZ environment variable handling from Guy Harris +** (guy@auspex.com). +*/ + +/*LINTLIBRARY*/ + +#include "private.h" +#include "tzfile.h" +#include "fcntl.h" + +#define ACCESS_MODE O_RDONLY + +#ifdef O_BINARY +#define OPEN_MODE (O_RDONLY | O_BINARY) +#endif /* defined O_BINARY */ +#ifndef O_BINARY +#define OPEN_MODE O_RDONLY +#endif /* !defined O_BINARY */ + +#ifndef WILDABBR +/* +** Someone might make incorrect use of a time zone abbreviation: +** 1. They might reference tzname[0] before calling tzset (explicitly +** or implicitly). +** 2. They might reference tzname[1] before calling tzset (explicitly +** or implicitly). +** 3. They might reference tzname[1] after setting to a time zone +** in which Daylight Saving Time is never observed. +** 4. They might reference tzname[0] after setting to a time zone +** in which Standard Time is never observed. +** 5. They might reference tm.TM_ZONE after calling offtime. +** What's best to do in the above cases is open to debate; +** for now, we just set things up so that in any of the five cases +** WILDABBR is used. Another possibility: initialize tzname[0] to the +** string "tzname[0] used before set", and similarly for the other cases. +** And another: initialize tzname[0] to "ERA", with an explanation in the +** manual page of what this "time zone abbreviation" means (doing this so +** that tzname[0] has the "normal" length of three characters). +*/ +#define WILDABBR " " +#endif /* !defined WILDABBR */ + +static char wildabbr[] = "WILDABBR"; + +static const char gmt[] = "GMT"; + +struct ttinfo { /* time type information */ + long tt_gmtoff; /* GMT offset in seconds */ + int tt_isdst; /* used to set tm_isdst */ + int tt_abbrind; /* abbreviation list index */ + int tt_ttisstd; /* TRUE if transition is std time */ +}; + +struct lsinfo { /* leap second information */ + time_t ls_trans; /* transition time */ + long ls_corr; /* correction to apply */ +}; + +#define BIGGEST(a, b) (((a) > (b)) ? (a) : (b)) + +#ifdef TZNAME_MAX +#define MY_TZNAME_MAX TZNAME_MAX +#endif /* defined TZNAME_MAX */ +#ifndef TZNAME_MAX +#define MY_TZNAME_MAX 255 +#endif /* !defined TZNAME_MAX */ + +struct state { + int leapcnt; + int timecnt; + int typecnt; + int charcnt; + time_t ats[TZ_MAX_TIMES]; + unsigned char types[TZ_MAX_TIMES]; + struct ttinfo ttis[TZ_MAX_TYPES]; + char chars[BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt), + (2 * (MY_TZNAME_MAX + 1)))]; + struct lsinfo lsis[TZ_MAX_LEAPS]; +}; + +struct rule { + int r_type; /* type of rule--see below */ + int r_day; /* day number of rule */ + int r_week; /* week number of rule */ + int r_mon; /* month number of rule */ + long r_time; /* transition time of rule */ +}; + +#define JULIAN_DAY 0 /* Jn - Julian day */ +#define DAY_OF_YEAR 1 /* n - day of year */ +#define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */ + +/* +** Prototypes for static functions. +*/ + +static long detzcode P((const char * codep)); +static const char * getzname P((const char * strp)); +static const char * getnum P((const char * strp, int * nump, int min, + int max)); +static const char * getsecs P((const char * strp, long * secsp)); +static const char * getoffset P((const char * strp, long * offsetp)); +static const char * getrule P((const char * strp, struct rule * rulep)); +static void gmtload P((struct state * sp)); +static void gmtsub P((const time_t * timep, long offset, + struct tm * tmp)); +static void localsub P((const time_t * timep, long offset, + struct tm * tmp)); +static int increment_overflow P((int * number, int delta)); +static int normalize_overflow P((int * tensptr, int * unitsptr, + int base)); +static void settzname P((void)); +static time_t time1 P((struct tm * tmp, void (* funcp)(), + long offset)); +static time_t time2 P((struct tm *tmp, void (* funcp)(), + long offset, int * okayp)); +static void timesub P((const time_t * timep, long offset, + const struct state * sp, struct tm * tmp)); +static int tmcomp P((const struct tm * atmp, + const struct tm * btmp)); +static time_t transtime P((time_t janfirst, int year, + const struct rule * rulep, long offset)); +static int tzload P((const char * name, struct state * sp)); +static int tzparse P((const char * name, struct state * sp, + int lastditch)); + +#ifdef ALL_STATE +static struct state * lclptr; +static struct state * gmtptr; +#endif /* defined ALL_STATE */ + +#ifndef ALL_STATE +static struct state lclmem; +static struct state gmtmem; +#define lclptr (&lclmem) +#define gmtptr (&gmtmem) +#endif /* State Farm */ + +#ifndef TZ_STRLEN_MAX +#define TZ_STRLEN_MAX 255 +#endif + +static char lcl_TZname[TZ_STRLEN_MAX + 1]; +static int lcl_is_set; +static int gmt_is_set; + +char * tzname[2] = { + wildabbr, + wildabbr +}; + +/* +** Section 4.12.3 of X3.159-1989 requires that +** Except for the strftime function, these functions [asctime, +** ctime, gmtime, localtime] return values in one of two static +** objects: a broken-down time structure and an array of char. +** Thanks to Paul Eggert (eggert@twinsun.com) for noting this. +*/ + +static struct tm tm; + +#ifdef USG_COMPAT +time_t timezone = 0; +int daylight = 0; +#endif /* defined USG_COMPAT */ + +#ifdef ALTZONE +time_t altzone = 0; +#endif /* defined ALTZONE */ + +static long +detzcode(codep) +const char * const codep; +{ + register long result; + register int i; + + result = 0; + for (i = 0; i < 4; ++i) + result = (result << 8) | (codep[i] & 0xff); + return result; +} + +static void +settzname P((void)) +{ + register const struct state * const sp = lclptr; + register int i; + + tzname[0] = wildabbr; + tzname[1] = wildabbr; +#ifdef USG_COMPAT + daylight = 0; + timezone = 0; +#endif /* defined USG_COMPAT */ +#ifdef ALTZONE + altzone = 0; +#endif /* defined ALTZONE */ +#ifdef ALL_STATE + if (sp == NULL) { + tzname[0] = tzname[1] = gmt; + return; + } +#endif /* defined ALL_STATE */ + for (i = 0; i < sp->typecnt; ++i) { + register const struct ttinfo * const ttisp = &sp->ttis[i]; + + tzname[ttisp->tt_isdst] = + (char *) &sp->chars[ttisp->tt_abbrind]; +#ifdef USG_COMPAT + if (ttisp->tt_isdst) + daylight = 1; + if (i == 0 || !ttisp->tt_isdst) + timezone = -(ttisp->tt_gmtoff); +#endif /* defined USG_COMPAT */ +#ifdef ALTZONE + if (i == 0 || ttisp->tt_isdst) + altzone = -(ttisp->tt_gmtoff); +#endif /* defined ALTZONE */ + } + /* + ** And to get the latest zone names into tzname. . . + */ + for (i = 0; i < sp->timecnt; ++i) { + register const struct ttinfo * const ttisp = + &sp->ttis[ + sp->types[i]]; + + tzname[ttisp->tt_isdst] = + (char *) &sp->chars[ttisp->tt_abbrind]; + } +} + +static int +tzload(name, sp) +register const char * name; +register struct state * const sp; +{ + register const char * p; + register int i; + register int fid; + + if (name == NULL && (name = TZDEFAULT) == NULL) + return -1; + { + register int doaccess; + char fullname[FILENAME_MAX + 1]; + + if (name[0] == ':') + ++name; + doaccess = name[0] == '/'; + if (!doaccess) { + if ((p = TZDIR) == NULL) + return -1; + if ((strlen(p) + strlen(name) + 1) >= sizeof fullname) + return -1; + (void) strcpy(fullname, p); + (void) strcat(fullname, "/"); + (void) strcat(fullname, name); + /* + ** Set doaccess if '.' (as in "../") shows up in name. + */ + if (strchr(name, '.') != NULL) + doaccess = TRUE; + name = fullname; + } + if (doaccess && access(name, ACCESS_MODE) != 0) + return -1; + if ((fid = open(name, OPEN_MODE)) == -1) + return -1; + } + { + register const struct tzhead * tzhp; + char buf[sizeof *sp + sizeof *tzhp]; + int ttisstdcnt; + + i = read(fid, buf, sizeof buf); + if (close(fid) != 0 || i < sizeof *tzhp) + return -1; + tzhp = (struct tzhead *) buf; + ttisstdcnt = (int) detzcode(tzhp->tzh_ttisstdcnt); + sp->leapcnt = (int) detzcode(tzhp->tzh_leapcnt); + sp->timecnt = (int) detzcode(tzhp->tzh_timecnt); + sp->typecnt = (int) detzcode(tzhp->tzh_typecnt); + sp->charcnt = (int) detzcode(tzhp->tzh_charcnt); + if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS || + sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES || + sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES || + sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS || + (ttisstdcnt != sp->typecnt && ttisstdcnt != 0)) + return -1; + if (i < sizeof *tzhp + + sp->timecnt * (4 + sizeof (char)) + + sp->typecnt * (4 + 2 * sizeof (char)) + + sp->charcnt * sizeof (char) + + sp->leapcnt * 2 * 4 + + ttisstdcnt * sizeof (char)) + return -1; + p = buf + sizeof *tzhp; + for (i = 0; i < sp->timecnt; ++i) { + sp->ats[i] = detzcode(p); + p += 4; + } + for (i = 0; i < sp->timecnt; ++i) { + sp->types[i] = (unsigned char) *p++; + if (sp->types[i] >= sp->typecnt) + return -1; + } + for (i = 0; i < sp->typecnt; ++i) { + register struct ttinfo * ttisp; + + ttisp = &sp->ttis[i]; + ttisp->tt_gmtoff = detzcode(p); + p += 4; + ttisp->tt_isdst = (unsigned char) *p++; + if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1) + return -1; + ttisp->tt_abbrind = (unsigned char) *p++; + if (ttisp->tt_abbrind < 0 || + ttisp->tt_abbrind > sp->charcnt) + return -1; + } + for (i = 0; i < sp->charcnt; ++i) + sp->chars[i] = *p++; + sp->chars[i] = '\0'; /* ensure '\0' at end */ + for (i = 0; i < sp->leapcnt; ++i) { + register struct lsinfo * lsisp; + + lsisp = &sp->lsis[i]; + lsisp->ls_trans = detzcode(p); + p += 4; + lsisp->ls_corr = detzcode(p); + p += 4; + } + for (i = 0; i < sp->typecnt; ++i) { + register struct ttinfo * ttisp; + + ttisp = &sp->ttis[i]; + if (ttisstdcnt == 0) + ttisp->tt_ttisstd = FALSE; + else { + ttisp->tt_ttisstd = *p++; + if (ttisp->tt_ttisstd != TRUE && + ttisp->tt_ttisstd != FALSE) + return -1; + } + } + } + return 0; +} + +static const int mon_lengths[2][MONSPERYEAR] = { + { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, + { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } +}; + +static const int year_lengths[2] = { + DAYSPERNYEAR, DAYSPERLYEAR +}; + +/* +** Given a pointer into a time zone string, scan until a character that is not +** a valid character in a zone name is found. Return a pointer to that +** character. +*/ + +static const char * +getzname(strp) +register const char * strp; +{ + register char c; + + while ((c = *strp) != '\0' && !isdigit(c) && c != ',' && c != '-' && + c != '+') + ++strp; + return strp; +} + +/* +** Given a pointer into a time zone string, extract a number from that string. +** Check that the number is within a specified range; if it is not, return +** NULL. +** Otherwise, return a pointer to the first character not part of the number. +*/ + +static const char * +getnum(strp, nump, min, max) +register const char * strp; +int * const nump; +const int min; +const int max; +{ + register char c; + register int num; + + if (strp == NULL || !isdigit(*strp)) + return NULL; + num = 0; + while ((c = *strp) != '\0' && isdigit(c)) { + num = num * 10 + (c - '0'); + if (num > max) + return NULL; /* illegal value */ + ++strp; + } + if (num < min) + return NULL; /* illegal value */ + *nump = num; + return strp; +} + +/* +** Given a pointer into a time zone string, extract a number of seconds, +** in hh[:mm[:ss]] form, from the string. +** If any error occurs, return NULL. +** Otherwise, return a pointer to the first character not part of the number +** of seconds. +*/ + +static const char * +getsecs(strp, secsp) +register const char * strp; +long * const secsp; +{ + int num; + + /* + ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like + ** "M10.4.6/26", which does not conform to Posix, + ** but which specifies the equivalent of + ** ``02:00 on the first Sunday on or after 23 Oct''. + */ + strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); + if (strp == NULL) + return NULL; + *secsp = num * (long) SECSPERHOUR; + if (*strp == ':') { + ++strp; + strp = getnum(strp, &num, 0, MINSPERHOUR - 1); + if (strp == NULL) + return NULL; + *secsp += num * SECSPERMIN; + if (*strp == ':') { + ++strp; + /* `SECSPERMIN' allows for leap seconds. */ + strp = getnum(strp, &num, 0, SECSPERMIN); + if (strp == NULL) + return NULL; + *secsp += num; + } + } + return strp; +} + +/* +** Given a pointer into a time zone string, extract an offset, in +** [+-]hh[:mm[:ss]] form, from the string. +** If any error occurs, return NULL. +** Otherwise, return a pointer to the first character not part of the time. +*/ + +static const char * +getoffset(strp, offsetp) +register const char * strp; +long * const offsetp; +{ + register int neg; + + if (*strp == '-') { + neg = 1; + ++strp; + } else if (isdigit(*strp) || *strp++ == '+') + neg = 0; + else return NULL; /* illegal offset */ + strp = getsecs(strp, offsetp); + if (strp == NULL) + return NULL; /* illegal time */ + if (neg) + *offsetp = -*offsetp; + return strp; +} + +/* +** Given a pointer into a time zone string, extract a rule in the form +** date[/time]. See POSIX section 8 for the format of "date" and "time". +** If a valid rule is not found, return NULL. +** Otherwise, return a pointer to the first character not part of the rule. +*/ + +static const char * +getrule(strp, rulep) +const char * strp; +register struct rule * const rulep; +{ + if (*strp == 'J') { + /* + ** Julian day. + */ + rulep->r_type = JULIAN_DAY; + ++strp; + strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); + } else if (*strp == 'M') { + /* + ** Month, week, day. + */ + rulep->r_type = MONTH_NTH_DAY_OF_WEEK; + ++strp; + strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); + if (strp == NULL) + return NULL; + if (*strp++ != '.') + return NULL; + strp = getnum(strp, &rulep->r_week, 1, 5); + if (strp == NULL) + return NULL; + if (*strp++ != '.') + return NULL; + strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); + } else if (isdigit(*strp)) { + /* + ** Day of year. + */ + rulep->r_type = DAY_OF_YEAR; + strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); + } else return NULL; /* invalid format */ + if (strp == NULL) + return NULL; + if (*strp == '/') { + /* + ** Time specified. + */ + ++strp; + strp = getsecs(strp, &rulep->r_time); + } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ + return strp; +} + +/* +** Given the Epoch-relative time of January 1, 00:00:00 GMT, in a year, the +** year, a rule, and the offset from GMT at the time that rule takes effect, +** calculate the Epoch-relative time that rule takes effect. +*/ + +static time_t +transtime(janfirst, year, rulep, offset) +const time_t janfirst; +const int year; +register const struct rule * const rulep; +const long offset; +{ + register int leapyear; + register time_t value; + register int i; + int d, m1, yy0, yy1, yy2, dow; + + INITIALIZE(value); + leapyear = isleap(year); + switch (rulep->r_type) { + + case JULIAN_DAY: + /* + ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap + ** years. + ** In non-leap years, or if the day number is 59 or less, just + ** add SECSPERDAY times the day number-1 to the time of + ** January 1, midnight, to get the day. + */ + value = janfirst + (rulep->r_day - 1) * SECSPERDAY; + if (leapyear && rulep->r_day >= 60) + value += SECSPERDAY; + break; + + case DAY_OF_YEAR: + /* + ** n - day of year. + ** Just add SECSPERDAY times the day number to the time of + ** January 1, midnight, to get the day. + */ + value = janfirst + rulep->r_day * SECSPERDAY; + break; + + case MONTH_NTH_DAY_OF_WEEK: + /* + ** Mm.n.d - nth "dth day" of month m. + */ + value = janfirst; + for (i = 0; i < rulep->r_mon - 1; ++i) + value += mon_lengths[leapyear][i] * SECSPERDAY; + + /* + ** Use Zeller's Congruence to get day-of-week of first day of + ** month. + */ + m1 = (rulep->r_mon + 9) % 12 + 1; + yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; + yy1 = yy0 / 100; + yy2 = yy0 % 100; + dow = ((26 * m1 - 2) / 10 + + 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; + if (dow < 0) + dow += DAYSPERWEEK; + + /* + ** "dow" is the day-of-week of the first day of the month. Get + ** the day-of-month (zero-origin) of the first "dow" day of the + ** month. + */ + d = rulep->r_day - dow; + if (d < 0) + d += DAYSPERWEEK; + for (i = 1; i < rulep->r_week; ++i) { + if (d + DAYSPERWEEK >= + mon_lengths[leapyear][rulep->r_mon - 1]) + break; + d += DAYSPERWEEK; + } + + /* + ** "d" is the day-of-month (zero-origin) of the day we want. + */ + value += d * SECSPERDAY; + break; + } + + /* + ** "value" is the Epoch-relative time of 00:00:00 GMT on the day in + ** question. To get the Epoch-relative time of the specified local + ** time on that day, add the transition time and the current offset + ** from GMT. + */ + return value + rulep->r_time + offset; +} + +/* +** Given a POSIX section 8-style TZ string, fill in the rule tables as +** appropriate. +*/ + +static int +tzparse(name, sp, lastditch) +const char * name; +register struct state * const sp; +const int lastditch; +{ + const char * stdname; + const char * dstname; + size_t stdlen; + size_t dstlen; + long stdoffset; + long dstoffset; + register time_t * atp; + register unsigned char * typep; + register char * cp; + register int load_result; + + INITIALIZE(dstname); + stdname = name; + if (lastditch) { + stdlen = strlen(name); /* length of standard zone name */ + name += stdlen; + if (stdlen >= sizeof sp->chars) + stdlen = (sizeof sp->chars) - 1; + } else { + name = getzname(name); + stdlen = name - stdname; + if (stdlen < 3) + return -1; + } + if (*name == '\0') + return -1; /* was "stdoffset = 0;" */ + else { + name = getoffset(name, &stdoffset); + if (name == NULL) + return -1; + } + load_result = tzload(TZDEFRULES, sp); + if (load_result != 0) + sp->leapcnt = 0; /* so, we're off a little */ + if (*name != '\0') { + dstname = name; + name = getzname(name); + dstlen = name - dstname; /* length of DST zone name */ + if (dstlen < 3) + return -1; + if (*name != '\0' && *name != ',' && *name != ';') { + name = getoffset(name, &dstoffset); + if (name == NULL) + return -1; + } else dstoffset = stdoffset - SECSPERHOUR; + if (*name == ',' || *name == ';') { + struct rule start; + struct rule end; + register int year; + register time_t janfirst; + time_t starttime; + time_t endtime; + + ++name; + if ((name = getrule(name, &start)) == NULL) + return -1; + if (*name++ != ',') + return -1; + if ((name = getrule(name, &end)) == NULL) + return -1; + if (*name != '\0') + return -1; + sp->typecnt = 2; /* standard time and DST */ + /* + ** Two transitions per year, from EPOCH_YEAR to 2037. + */ + sp->timecnt = 2 * (2037 - EPOCH_YEAR + 1); + if (sp->timecnt > TZ_MAX_TIMES) + return -1; + sp->ttis[0].tt_gmtoff = -dstoffset; + sp->ttis[0].tt_isdst = 1; + sp->ttis[0].tt_abbrind = stdlen + 1; + sp->ttis[1].tt_gmtoff = -stdoffset; + sp->ttis[1].tt_isdst = 0; + sp->ttis[1].tt_abbrind = 0; + atp = sp->ats; + typep = sp->types; + janfirst = 0; + for (year = EPOCH_YEAR; year <= 2037; ++year) { + starttime = transtime(janfirst, year, &start, + stdoffset); + endtime = transtime(janfirst, year, &end, + dstoffset); + if (starttime > endtime) { + *atp++ = endtime; + *typep++ = 1; /* DST ends */ + *atp++ = starttime; + *typep++ = 0; /* DST begins */ + } else { + *atp++ = starttime; + *typep++ = 0; /* DST begins */ + *atp++ = endtime; + *typep++ = 1; /* DST ends */ + } + janfirst += year_lengths[isleap(year)] * + SECSPERDAY; + } + } else { + int sawstd; + int sawdst; + long stdfix; + long dstfix; + long oldfix; + int isdst; + register int i; + + if (*name != '\0') + return -1; + if (load_result != 0) + return -1; + /* + ** Compute the difference between the real and + ** prototype standard and summer time offsets + ** from GMT, and put the real standard and summer + ** time offsets into the rules in place of the + ** prototype offsets. + */ + sawstd = FALSE; + sawdst = FALSE; + stdfix = 0; + dstfix = 0; + for (i = 0; i < sp->typecnt; ++i) { + if (sp->ttis[i].tt_isdst) { + oldfix = dstfix; + dstfix = sp->ttis[i].tt_gmtoff + + dstoffset; + if (sawdst && (oldfix != dstfix)) + return -1; + sp->ttis[i].tt_gmtoff = -dstoffset; + sp->ttis[i].tt_abbrind = stdlen + 1; + sawdst = TRUE; + } else { + oldfix = stdfix; + stdfix = sp->ttis[i].tt_gmtoff + + stdoffset; + if (sawstd && (oldfix != stdfix)) + return -1; + sp->ttis[i].tt_gmtoff = -stdoffset; + sp->ttis[i].tt_abbrind = 0; + sawstd = TRUE; + } + } + /* + ** Make sure we have both standard and summer time. + */ + if (!sawdst || !sawstd) + return -1; + /* + ** Now correct the transition times by shifting + ** them by the difference between the real and + ** prototype offsets. Note that this difference + ** can be different in standard and summer time; + ** the prototype probably has a 1-hour difference + ** between standard and summer time, but a different + ** difference can be specified in TZ. + */ + isdst = FALSE; /* we start in standard time */ + for (i = 0; i < sp->timecnt; ++i) { + register const struct ttinfo * ttisp; + + /* + ** If summer time is in effect, and the + ** transition time was not specified as + ** standard time, add the summer time + ** offset to the transition time; + ** otherwise, add the standard time offset + ** to the transition time. + */ + ttisp = &sp->ttis[sp->types[i]]; + sp->ats[i] += + (isdst && !ttisp->tt_ttisstd) ? + dstfix : stdfix; + isdst = ttisp->tt_isdst; + } + } + } else { + dstlen = 0; + sp->typecnt = 1; /* only standard time */ + sp->timecnt = 0; + sp->ttis[0].tt_gmtoff = -stdoffset; + sp->ttis[0].tt_isdst = 0; + sp->ttis[0].tt_abbrind = 0; + } + sp->charcnt = stdlen + 1; + if (dstlen != 0) + sp->charcnt += dstlen + 1; + if (sp->charcnt > sizeof sp->chars) + return -1; + cp = sp->chars; + (void) strncpy(cp, stdname, stdlen); + cp += stdlen; + *cp++ = '\0'; + if (dstlen != 0) { + (void) strncpy(cp, dstname, dstlen); + *(cp + dstlen) = '\0'; + } + return 0; +} + +static void +gmtload(sp) +struct state * const sp; +{ + if (tzload(gmt, sp) != 0) + (void) tzparse(gmt, sp, TRUE); +} + +#ifndef STD_INSPIRED +/* +** A non-static declaration of tzsetwall in a system header file +** may cause a warning about this upcoming static declaration... +*/ +static +#endif /* !defined STD_INSPIRED */ +void +tzsetwall P((void)) +{ + if (lcl_is_set < 0) + return; + lcl_is_set = -1; + +#ifdef ALL_STATE + if (lclptr == NULL) { + lclptr = (struct state *) malloc(sizeof *lclptr); + if (lclptr == NULL) { + settzname(); /* all we can do */ + return; + } + } +#endif /* defined ALL_STATE */ + if (tzload((char *) NULL, lclptr) != 0) + gmtload(lclptr); + settzname(); +} + +void +tzset P((void)) +{ + register const char * name; + + name = getenv("TZ"); + if (name == NULL) { + tzsetwall(); + return; + } + + if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) + return; + lcl_is_set = (strlen(name) < sizeof(lcl_TZname)); + if (lcl_is_set) + (void) strcpy(lcl_TZname, name); + +#ifdef ALL_STATE + if (lclptr == NULL) { + lclptr = (struct state *) malloc(sizeof *lclptr); + if (lclptr == NULL) { + settzname(); /* all we can do */ + return; + } + } +#endif /* defined ALL_STATE */ + if (*name == '\0') { + /* + ** User wants it fast rather than right. + */ + lclptr->leapcnt = 0; /* so, we're off a little */ + lclptr->timecnt = 0; + lclptr->ttis[0].tt_gmtoff = 0; + lclptr->ttis[0].tt_abbrind = 0; + (void) strcpy(lclptr->chars, gmt); + } else if (tzload(name, lclptr) != 0) + if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0) + (void) gmtload(lclptr); + settzname(); +} + +/* +** The easy way to behave "as if no library function calls" localtime +** is to not call it--so we drop its guts into "localsub", which can be +** freely called. (And no, the PANS doesn't require the above behavior-- +** but it *is* desirable.) +** +** The unused offset argument is for the benefit of mktime variants. +*/ + +/*ARGSUSED*/ +static void +localsub(timep, offset, tmp) +const time_t * const timep; +const long offset; +struct tm * const tmp; +{ + register const struct state * sp; + register const struct ttinfo * ttisp; + register int i; + const time_t t = *timep; + + sp = lclptr; +#ifdef ALL_STATE + if (sp == NULL) { + gmtsub(timep, offset, tmp); + return; + } +#endif /* defined ALL_STATE */ + if (sp->timecnt == 0 || t < sp->ats[0]) { + i = 0; + while (sp->ttis[i].tt_isdst) + if (++i >= sp->typecnt) { + i = 0; + break; + } + } else { + for (i = 1; i < sp->timecnt; ++i) + if (t < sp->ats[i]) + break; + i = sp->types[i - 1]; + } + ttisp = &sp->ttis[i]; + /* + ** To get (wrong) behavior that's compatible with System V Release 2.0 + ** you'd replace the statement below with + ** t += ttisp->tt_gmtoff; + ** timesub(&t, 0L, sp, tmp); + */ + timesub(&t, ttisp->tt_gmtoff, sp, tmp); + tmp->tm_isdst = ttisp->tt_isdst; + tzname[tmp->tm_isdst] = (char *) &sp->chars[ttisp->tt_abbrind]; +#ifdef TM_ZONE + tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind]; +#endif /* defined TM_ZONE */ +} + +struct tm * +localtime(timep) +const time_t * const timep; +{ + tzset(); + localsub(timep, 0L, &tm); + return &tm; +} + +/* +** gmtsub is to gmtime as localsub is to localtime. +*/ + +static void +gmtsub(timep, offset, tmp) +const time_t * const timep; +const long offset; +struct tm * const tmp; +{ + if (!gmt_is_set) { + gmt_is_set = TRUE; +#ifdef ALL_STATE + gmtptr = (struct state *) malloc(sizeof *gmtptr); + if (gmtptr != NULL) +#endif /* defined ALL_STATE */ + gmtload(gmtptr); + } + timesub(timep, offset, gmtptr, tmp); +#ifdef TM_ZONE + /* + ** Could get fancy here and deliver something such as + ** "GMT+xxxx" or "GMT-xxxx" if offset is non-zero, + ** but this is no time for a treasure hunt. + */ + if (offset != 0) + tmp->TM_ZONE = wildabbr; + else { +#ifdef ALL_STATE + if (gmtptr == NULL) + tmp->TM_ZONE = gmt; + else tmp->TM_ZONE = gmtptr->chars; +#endif /* defined ALL_STATE */ +#ifndef ALL_STATE + tmp->TM_ZONE = gmtptr->chars; +#endif /* State Farm */ + } +#endif /* defined TM_ZONE */ +} + +struct tm * +gmtime(timep) +const time_t * const timep; +{ + gmtsub(timep, 0L, &tm); + return &tm; +} + +#ifdef STD_INSPIRED + +struct tm * +offtime(timep, offset) +const time_t * const timep; +const long offset; +{ + gmtsub(timep, offset, &tm); + return &tm; +} + +#endif /* defined STD_INSPIRED */ + +static void +timesub(timep, offset, sp, tmp) +const time_t * const timep; +const long offset; +register const struct state * const sp; +register struct tm * const tmp; +{ + register const struct lsinfo * lp; + register long days; + register long rem; + register int y; + register int yleap; + register const int * ip; + register long corr; + register int hit; + register int i; + + corr = 0; + hit = 0; +#ifdef ALL_STATE + i = (sp == NULL) ? 0 : sp->leapcnt; +#endif /* defined ALL_STATE */ +#ifndef ALL_STATE + i = sp->leapcnt; +#endif /* State Farm */ + while (--i >= 0) { + lp = &sp->lsis[i]; + if (*timep >= lp->ls_trans) { + if (*timep == lp->ls_trans) { + hit = ((i == 0 && lp->ls_corr > 0) || + lp->ls_corr > sp->lsis[i - 1].ls_corr); + if (hit) + while (i > 0 && + sp->lsis[i].ls_trans == + sp->lsis[i - 1].ls_trans + 1 && + sp->lsis[i].ls_corr == + sp->lsis[i - 1].ls_corr + 1) { + ++hit; + --i; + } + } + corr = lp->ls_corr; + break; + } + } + days = *timep / SECSPERDAY; + rem = *timep % SECSPERDAY; +#ifdef mc68k + if (*timep == 0x80000000) { + /* + ** A 3B1 muffs the division on the most negative number. + */ + days = -24855; + rem = -11648; + } +#endif /* mc68k */ + rem += (offset - corr); + while (rem < 0) { + rem += SECSPERDAY; + --days; + } + while (rem >= SECSPERDAY) { + rem -= SECSPERDAY; + ++days; + } + tmp->tm_hour = (int) (rem / SECSPERHOUR); + rem = rem % SECSPERHOUR; + tmp->tm_min = (int) (rem / SECSPERMIN); + tmp->tm_sec = (int) (rem % SECSPERMIN); + if (hit) + /* + ** A positive leap second requires a special + ** representation. This uses "... ??:59:60" et seq. + */ + tmp->tm_sec += hit; + tmp->tm_wday = (int) ((EPOCH_WDAY + days) % DAYSPERWEEK); + if (tmp->tm_wday < 0) + tmp->tm_wday += DAYSPERWEEK; + y = EPOCH_YEAR; + if (days >= 0) + for ( ; ; ) { + yleap = isleap(y); + if (days < (long) year_lengths[yleap]) + break; + ++y; + days = days - (long) year_lengths[yleap]; + } + else do { + --y; + yleap = isleap(y); + days = days + (long) year_lengths[yleap]; + } while (days < 0); + tmp->tm_year = y - TM_YEAR_BASE; + tmp->tm_yday = (int) days; + ip = mon_lengths[yleap]; + for (tmp->tm_mon = 0; days >= (long) ip[tmp->tm_mon]; ++(tmp->tm_mon)) + days = days - (long) ip[tmp->tm_mon]; + tmp->tm_mday = (int) (days + 1); + tmp->tm_isdst = 0; +#ifdef TM_GMTOFF + tmp->TM_GMTOFF = offset; +#endif /* defined TM_GMTOFF */ +} + +char * +ctime(timep) +const time_t * const timep; +{ +/* +** Section 4.12.3.2 of X3.159-1989 requires that +** The ctime funciton converts the calendar time pointed to by timer +** to local time in the form of a string. It is equivalent to +** asctime(localtime(timer)) +*/ + return asctime(localtime(timep)); +} + +/* +** Adapted from code provided by Robert Elz, who writes: +** The "best" way to do mktime I think is based on an idea of Bob +** Kridle's (so its said...) from a long time ago. (mtxinu!kridle now). +** It does a binary search of the time_t space. Since time_t's are +** just 32 bits, its a max of 32 iterations (even at 64 bits it +** would still be very reasonable). +*/ + +#ifndef WRONG +#define WRONG (-1) +#endif /* !defined WRONG */ + +/* +** Simplified normalize logic courtesy Paul Eggert (eggert@twinsun.com). +*/ + +static int +increment_overflow(number, delta) +int * number; +int delta; +{ + int number0; + + number0 = *number; + *number += delta; + return (*number < number0) != (delta < 0); +} + +static int +normalize_overflow(tensptr, unitsptr, base) +int * const tensptr; +int * const unitsptr; +const int base; +{ + register int tensdelta; + + tensdelta = (*unitsptr >= 0) ? + (*unitsptr / base) : + (-1 - (-1 - *unitsptr) / base); + *unitsptr -= tensdelta * base; + return increment_overflow(tensptr, tensdelta); +} + +static int +tmcomp(atmp, btmp) +register const struct tm * const atmp; +register const struct tm * const btmp; +{ + register int result; + + if ((result = (atmp->tm_year - btmp->tm_year)) == 0 && + (result = (atmp->tm_mon - btmp->tm_mon)) == 0 && + (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && + (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && + (result = (atmp->tm_min - btmp->tm_min)) == 0) + result = atmp->tm_sec - btmp->tm_sec; + return result; +} + +static time_t +time2(tmp, funcp, offset, okayp) +struct tm * const tmp; +void (* const funcp)(); +const long offset; +int * const okayp; +{ + register const struct state * sp; + register int dir; + register int bits; + register int i, j ; + register int saved_seconds; + time_t newt; + time_t t; + struct tm yourtm, mytm; + + *okayp = FALSE; + yourtm = *tmp; + if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) + return WRONG; + if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) + return WRONG; + if (normalize_overflow(&yourtm.tm_year, &yourtm.tm_mon, MONSPERYEAR)) + return WRONG; + /* + ** Turn yourtm.tm_year into an actual year number for now. + ** It is converted back to an offset from TM_YEAR_BASE later. + */ + if (increment_overflow(&yourtm.tm_year, TM_YEAR_BASE)) + return WRONG; + while (yourtm.tm_mday <= 0) { + if (increment_overflow(&yourtm.tm_year, -1)) + return WRONG; + yourtm.tm_mday += year_lengths[isleap(yourtm.tm_year)]; + } + while (yourtm.tm_mday > DAYSPERLYEAR) { + yourtm.tm_mday -= year_lengths[isleap(yourtm.tm_year)]; + if (increment_overflow(&yourtm.tm_year, 1)) + return WRONG; + } + for ( ; ; ) { + i = mon_lengths[isleap(yourtm.tm_year)][yourtm.tm_mon]; + if (yourtm.tm_mday <= i) + break; + yourtm.tm_mday -= i; + if (++yourtm.tm_mon >= MONSPERYEAR) { + yourtm.tm_mon = 0; + if (increment_overflow(&yourtm.tm_year, 1)) + return WRONG; + } + } + if (increment_overflow(&yourtm.tm_year, -TM_YEAR_BASE)) + return WRONG; + if (yourtm.tm_year + TM_YEAR_BASE < EPOCH_YEAR) { + /* + ** We can't set tm_sec to 0, because that might push the + ** time below the minimum representable time. + ** Set tm_sec to 59 instead. + ** This assumes that the minimum representable time is + ** not in the same minute that a leap second was deleted from, + ** which is a safer assumption than using 58 would be. + */ + if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) + return WRONG; + saved_seconds = yourtm.tm_sec; + yourtm.tm_sec = SECSPERMIN - 1; + } else { + saved_seconds = yourtm.tm_sec; + yourtm.tm_sec = 0; + } + /* + ** Calculate the number of magnitude bits in a time_t + ** (this works regardless of whether time_t is + ** signed or unsigned, though lint complains if unsigned). + */ + for (bits = 0, t = 1; t > 0; ++bits, t <<= 1) + continue; + /* + ** If time_t is signed, then 0 is the median value, + ** if time_t is unsigned, then 1 << bits is median. + */ + t = (t < 0) ? 0 : ((time_t) 1 << bits); + for ( ; ; ) { + (*funcp)(&t, offset, &mytm); + dir = tmcomp(&mytm, &yourtm); + if (dir != 0) { + if (bits-- < 0) + return WRONG; + if (bits < 0) + --t; + else if (dir > 0) + t -= (time_t) 1 << bits; + else t += (time_t) 1 << bits; + continue; + } + if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) + break; + /* + ** Right time, wrong type. + ** Hunt for right time, right type. + ** It's okay to guess wrong since the guess + ** gets checked. + */ + /* + ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's. + */ + sp = (const struct state *) + (((void *) funcp == (void *) localsub) ? + lclptr : gmtptr); +#ifdef ALL_STATE + if (sp == NULL) + return WRONG; +#endif /* defined ALL_STATE */ + for (i = 0; i < sp->typecnt; ++i) { + if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) + continue; + for (j = 0; j < sp->typecnt; ++j) { + if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) + continue; + newt = t + sp->ttis[j].tt_gmtoff - + sp->ttis[i].tt_gmtoff; + (*funcp)(&newt, offset, &mytm); + if (tmcomp(&mytm, &yourtm) != 0) + continue; + if (mytm.tm_isdst != yourtm.tm_isdst) + continue; + /* + ** We have a match. + */ + t = newt; + goto label; + } + } + return WRONG; + } +label: + newt = t + saved_seconds; + if ((newt < t) != (saved_seconds < 0)) + return WRONG; + t = newt; + (*funcp)(&t, offset, tmp); + *okayp = TRUE; + return t; +} + +static time_t +time1(tmp, funcp, offset) +struct tm * const tmp; +void (* const funcp)(); +const long offset; +{ + register time_t t; + register const struct state * sp; + register int samei, otheri; + int okay; + + if (tmp->tm_isdst > 1) + tmp->tm_isdst = 1; + t = time2(tmp, funcp, offset, &okay); +#ifdef PCTS + /* + ** PCTS code courtesy Grant Sullivan (grant@osf.org). + */ + if (okay) + return t; + if (tmp->tm_isdst < 0) + tmp->tm_isdst = 0; /* reset to std and try again */ +#endif /* defined PCTS */ +#ifndef PCTS + if (okay || tmp->tm_isdst < 0) + return t; +#endif /* !defined PCTS */ + /* + ** We're supposed to assume that somebody took a time of one type + ** and did some math on it that yielded a "struct tm" that's bad. + ** We try to divine the type they started from and adjust to the + ** type they need. + */ + /* + ** The (void *) casts are the benefit of SunOS 3.3 on Sun 2's. + */ + sp = (const struct state *) (((void *) funcp == (void *) localsub) ? + lclptr : gmtptr); +#ifdef ALL_STATE + if (sp == NULL) + return WRONG; +#endif /* defined ALL_STATE */ + for (samei = 0; samei < sp->typecnt; ++samei) { + if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) + continue; + for (otheri = 0; otheri < sp->typecnt; ++otheri) { + if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) + continue; + tmp->tm_sec += sp->ttis[otheri].tt_gmtoff - + sp->ttis[samei].tt_gmtoff; + tmp->tm_isdst = !tmp->tm_isdst; + t = time2(tmp, funcp, offset, &okay); + if (okay) + return t; + tmp->tm_sec -= sp->ttis[otheri].tt_gmtoff - + sp->ttis[samei].tt_gmtoff; + tmp->tm_isdst = !tmp->tm_isdst; + } + } + return WRONG; +} + +time_t +mktime(tmp) +struct tm * const tmp; +{ + tzset(); + return time1(tmp, localsub, 0L); +} + +#ifdef STD_INSPIRED + +time_t +timelocal(tmp) +struct tm * const tmp; +{ + tmp->tm_isdst = -1; /* in case it wasn't initialized */ + return mktime(tmp); +} + +time_t +timegm(tmp) +struct tm * const tmp; +{ + tmp->tm_isdst = 0; + return time1(tmp, gmtsub, 0L); +} + +time_t +timeoff(tmp, offset) +struct tm * const tmp; +const long offset; +{ + tmp->tm_isdst = 0; + return time1(tmp, gmtsub, offset); +} + +#endif /* defined STD_INSPIRED */ + +#ifdef CMUCS + +/* +** The following is supplied for compatibility with +** previous versions of the CMUCS runtime library. +*/ + +long +gtime(tmp) +struct tm * const tmp; +{ + const time_t t = mktime(tmp); + + if (t == WRONG) + return -1; + return t; +} + +#endif /* defined CMUCS */ + +/* +** XXX--is the below the right way to conditionalize?? +*/ + +#ifdef STD_INSPIRED + +/* +** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 +** shall correspond to "Wed Dec 31 23:59:59 GMT 1986", which +** is not the case if we are accounting for leap seconds. +** So, we provide the following conversion routines for use +** when exchanging timestamps with POSIX conforming systems. +*/ + +static long +leapcorr(timep) +time_t * timep; +{ + register struct state * sp; + register struct lsinfo * lp; + register int i; + + sp = lclptr; + i = sp->leapcnt; + while (--i >= 0) { + lp = &sp->lsis[i]; + if (*timep >= lp->ls_trans) + return lp->ls_corr; + } + return 0; +} + +time_t +time2posix(t) +time_t t; +{ + tzset(); + return t - leapcorr(&t); +} + +time_t +posix2time(t) +time_t t; +{ + time_t x; + time_t y; + + tzset(); + /* + ** For a positive leap second hit, the result + ** is not unique. For a negative leap second + ** hit, the corresponding time doesn't exist, + ** so we return an adjacent second. + */ + x = t + leapcorr(&t); + y = x - leapcorr(&x); + if (y < t) { + do { + x++; + y = x - leapcorr(&x); + } while (y < t); + if (t != y) + return x - 1; + } else if (y > t) { + do { + --x; + y = x - leapcorr(&x); + } while (y > t); + if (t != y) + return x + 1; + } + return x; +} + +#endif /* defined STD_INSPIRED */ |