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-rw-r--r--externals/tz/tz/tz.cpp1636
1 files changed, 1636 insertions, 0 deletions
diff --git a/externals/tz/tz/tz.cpp b/externals/tz/tz/tz.cpp
new file mode 100644
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+++ b/externals/tz/tz/tz.cpp
@@ -0,0 +1,1636 @@
+// SPDX-FileCopyrightText: 2023 yuzu Emulator Project
+// SPDX-FileCopyrightText: 1996 Arthur David Olson
+// SPDX-License-Identifier: BSD-2-Clause
+
+#include <climits>
+#include <cstring>
+#include <ctime>
+
+#include "tz.h"
+
+namespace Tz {
+
+namespace {
+#define EINVAL 22
+
+static Rule gmtmem{};
+static Rule* const gmtptr = &gmtmem;
+
+struct TzifHeader {
+ std::array<char, 4> tzh_magic; // "TZif"
+ std::array<char, 1> tzh_version;
+ std::array<char, 15> tzh_reserved;
+ std::array<char, 4> tzh_ttisutcnt;
+ std::array<char, 4> tzh_ttisstdcnt;
+ std::array<char, 4> tzh_leapcnt;
+ std::array<char, 4> tzh_timecnt;
+ std::array<char, 4> tzh_typecnt;
+ std::array<char, 4> tzh_charcnt;
+};
+static_assert(sizeof(TzifHeader) == 0x2C, "TzifHeader has the wrong size!");
+
+struct local_storage {
+ // Binary layout:
+ // char buf[2 * sizeof(TzifHeader) + 2 * sizeof(Rule) + 4 * TZ_MAX_TIMES];
+ std::span<const u8> binary;
+ Rule state;
+};
+static local_storage tzloadbody_local_storage;
+
+enum rtype : s32 {
+ JULIAN_DAY = 0,
+ DAY_OF_YEAR = 1,
+ MONTH_NTH_DAY_OF_WEEK = 2,
+};
+
+struct tzrule {
+ rtype r_type;
+ int r_day;
+ int r_week;
+ int r_mon;
+ s64 r_time;
+};
+static_assert(sizeof(tzrule) == 0x18, "tzrule has the wrong size!");
+
+constexpr static char UNSPEC[] = "-00";
+constexpr static char TZDEFRULESTRING[] = ",M3.2.0,M11.1.0";
+
+enum {
+ SECSPERMIN = 60,
+ MINSPERHOUR = 60,
+ SECSPERHOUR = SECSPERMIN * MINSPERHOUR,
+ HOURSPERDAY = 24,
+ DAYSPERWEEK = 7,
+ DAYSPERNYEAR = 365,
+ DAYSPERLYEAR = DAYSPERNYEAR + 1,
+ MONSPERYEAR = 12,
+ YEARSPERREPEAT = 400 /* years before a Gregorian repeat */
+};
+
+#define SECSPERDAY ((s64)SECSPERHOUR * HOURSPERDAY)
+
+#define DAYSPERREPEAT ((s64)400 * 365 + 100 - 4 + 1)
+#define SECSPERREPEAT ((int_fast64_t)DAYSPERREPEAT * SECSPERDAY)
+#define AVGSECSPERYEAR (SECSPERREPEAT / YEARSPERREPEAT)
+
+enum {
+ TM_SUNDAY,
+ TM_MONDAY,
+ TM_TUESDAY,
+ TM_WEDNESDAY,
+ TM_THURSDAY,
+ TM_FRIDAY,
+ TM_SATURDAY,
+};
+
+enum {
+ TM_JANUARY,
+ TM_FEBRUARY,
+ TM_MARCH,
+ TM_APRIL,
+ TM_MAY,
+ TM_JUNE,
+ TM_JULY,
+ TM_AUGUST,
+ TM_SEPTEMBER,
+ TM_OCTOBER,
+ TM_NOVEMBER,
+ TM_DECEMBER,
+};
+
+constexpr s32 TM_YEAR_BASE = 1900;
+constexpr s32 TM_WDAY_BASE = TM_MONDAY;
+constexpr s32 EPOCH_YEAR = 1970;
+constexpr s32 EPOCH_WDAY = TM_THURSDAY;
+
+#define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
+
+static constexpr std::array<std::array<int, MONSPERYEAR>, 2> mon_lengths = { {
+ {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 constexpr std::array<int, 2> year_lengths = {
+ DAYSPERNYEAR,
+ DAYSPERLYEAR,
+};
+
+constexpr static time_t leaps_thru_end_of_nonneg(time_t y) {
+ return y / 4 - y / 100 + y / 400;
+}
+
+constexpr static time_t leaps_thru_end_of(time_t y) {
+ return (y < 0 ? -1 - leaps_thru_end_of_nonneg(-1 - y) : leaps_thru_end_of_nonneg(y));
+}
+
+#define TWOS_COMPLEMENT(t) ((t) ~(t)0 < 0)
+
+s32 detzcode(const char* const codep) {
+ s32 result;
+ int i;
+ s32 one = 1;
+ s32 halfmaxval = one << (32 - 2);
+ s32 maxval = halfmaxval - 1 + halfmaxval;
+ s32 minval = -1 - maxval;
+
+ result = codep[0] & 0x7f;
+ for (i = 1; i < 4; ++i) {
+ result = (result << 8) | (codep[i] & 0xff);
+ }
+
+ if (codep[0] & 0x80) {
+ /* Do two's-complement negation even on non-two's-complement machines.
+ If the result would be minval - 1, return minval. */
+ result -= !TWOS_COMPLEMENT(s32) && result != 0;
+ result += minval;
+ }
+ return result;
+}
+
+int_fast64_t detzcode64(const char* const codep) {
+ int_fast64_t result;
+ int i;
+ int_fast64_t one = 1;
+ int_fast64_t halfmaxval = one << (64 - 2);
+ int_fast64_t maxval = halfmaxval - 1 + halfmaxval;
+ int_fast64_t minval = -static_cast<int_fast64_t>(TWOS_COMPLEMENT(int_fast64_t)) - maxval;
+
+ result = codep[0] & 0x7f;
+ for (i = 1; i < 8; ++i) {
+ result = (result << 8) | (codep[i] & 0xff);
+ }
+
+ if (codep[0] & 0x80) {
+ /* Do two's-complement negation even on non-two's-complement machines.
+ If the result would be minval - 1, return minval. */
+ result -= !TWOS_COMPLEMENT(int_fast64_t) && result != 0;
+ result += minval;
+ }
+ return result;
+}
+
+/* Initialize *S to a value based on UTOFF, ISDST, and DESIGIDX. */
+constexpr void init_ttinfo(ttinfo* s, s64 utoff, bool isdst, int desigidx) {
+ s->tt_utoff = static_cast<s32>(utoff);
+ s->tt_isdst = isdst;
+ s->tt_desigidx = desigidx;
+ s->tt_ttisstd = false;
+ s->tt_ttisut = false;
+}
+
+/* Return true if SP's time type I does not specify local time. */
+bool ttunspecified(struct Rule const* sp, int i) {
+ char const* abbr = &sp->chars[sp->ttis[i].tt_desigidx];
+ /* memcmp is likely faster than strcmp, and is safe due to CHARS_EXTRA. */
+ return memcmp(abbr, UNSPEC, sizeof(UNSPEC)) == 0;
+}
+
+bool typesequiv(const Rule* sp, int a, int b) {
+ bool result;
+
+ if (sp == nullptr || a < 0 || a >= sp->typecnt || b < 0 || b >= sp->typecnt) {
+ result = false;
+ }
+ else {
+ /* Compare the relevant members of *AP and *BP.
+ Ignore tt_ttisstd and tt_ttisut, as they are
+ irrelevant now and counting them could cause
+ sp->goahead to mistakenly remain false. */
+ const ttinfo* ap = &sp->ttis[a];
+ const ttinfo* bp = &sp->ttis[b];
+ result = (ap->tt_utoff == bp->tt_utoff && ap->tt_isdst == bp->tt_isdst &&
+ (strcmp(&sp->chars[ap->tt_desigidx], &sp->chars[bp->tt_desigidx]) == 0));
+ }
+ return result;
+}
+
+constexpr const char* getqzname(const char* strp, const int delim) {
+ int c;
+
+ while ((c = *strp) != '\0' && c != delim) {
+ ++strp;
+ }
+ return strp;
+}
+
+/* Is C an ASCII digit? */
+constexpr bool is_digit(char c) {
+ return '0' <= c && c <= '9';
+}
+
+/*
+** Given a pointer into a timezone string, scan until a character that is not
+** a valid character in a time zone abbreviation is found.
+** Return a pointer to that character.
+*/
+
+constexpr const char* getzname(const char* strp) {
+ char c;
+
+ while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && c != '+') {
+ ++strp;
+ }
+ return strp;
+}
+
+static const char* getnum(const char* strp, int* const nump, const int min, const int max) {
+ char c;
+ int num;
+
+ if (strp == nullptr || !is_digit(c = *strp)) {
+ return nullptr;
+ }
+ num = 0;
+ do {
+ num = num * 10 + (c - '0');
+ if (num > max) {
+ return nullptr; /* illegal value */
+ }
+ c = *++strp;
+ } while (is_digit(c));
+ if (num < min) {
+ return nullptr; /* illegal value */
+ }
+ *nump = num;
+ return strp;
+}
+
+/*
+** Given a pointer into a timezone 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.
+*/
+
+const char* getsecs(const char* strp, s64* const secsp) {
+ int num;
+ s64 secsperhour = SECSPERHOUR;
+
+ /*
+ ** '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 == nullptr) {
+ return nullptr;
+ }
+ *secsp = num * secsperhour;
+ if (*strp == ':') {
+ ++strp;
+ strp = getnum(strp, &num, 0, MINSPERHOUR - 1);
+ if (strp == nullptr) {
+ return nullptr;
+ }
+ *secsp += num * SECSPERMIN;
+ if (*strp == ':') {
+ ++strp;
+ /* 'SECSPERMIN' allows for leap seconds. */
+ strp = getnum(strp, &num, 0, SECSPERMIN);
+ if (strp == nullptr) {
+ return nullptr;
+ }
+ *secsp += num;
+ }
+ }
+ return strp;
+}
+
+/*
+** Given a pointer into a timezone 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.
+*/
+
+const char* getoffset(const char* strp, s64* const offsetp) {
+ bool neg = false;
+
+ if (*strp == '-') {
+ neg = true;
+ ++strp;
+ }
+ else if (*strp == '+') {
+ ++strp;
+ }
+ strp = getsecs(strp, offsetp);
+ if (strp == nullptr) {
+ return nullptr; /* illegal time */
+ }
+ if (neg) {
+ *offsetp = -*offsetp;
+ }
+ return strp;
+}
+
+constexpr const char* getrule(const char* strp, tzrule* 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 == nullptr) {
+ return nullptr;
+ }
+ if (*strp++ != '.') {
+ return nullptr;
+ }
+ strp = getnum(strp, &rulep->r_week, 1, 5);
+ if (strp == nullptr) {
+ return nullptr;
+ }
+ if (*strp++ != '.') {
+ return nullptr;
+ }
+ strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1);
+ }
+ else if (is_digit(*strp)) {
+ /*
+ ** Day of year.
+ */
+ rulep->r_type = DAY_OF_YEAR;
+ strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1);
+ }
+ else {
+ return nullptr;
+ } /* invalid format */
+ if (strp == nullptr) {
+ return nullptr;
+ }
+ if (*strp == '/') {
+ /*
+ ** Time specified.
+ */
+ ++strp;
+ strp = getoffset(strp, &rulep->r_time);
+ }
+ else {
+ rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */
+ }
+ return strp;
+}
+
+constexpr bool increment_overflow(int* ip, int j) {
+ int const i = *ip;
+
+ /*
+ ** If i >= 0 there can only be overflow if i + j > INT_MAX
+ ** or if j > INT_MAX - i; given i >= 0, INT_MAX - i cannot overflow.
+ ** If i < 0 there can only be overflow if i + j < INT_MIN
+ ** or if j < INT_MIN - i; given i < 0, INT_MIN - i cannot overflow.
+ */
+ if ((i >= 0) ? (j > INT_MAX - i) : (j < INT_MIN - i)) {
+ return true;
+ }
+ *ip += j;
+ return false;
+}
+
+constexpr bool increment_overflow32(s64* const lp, int const m) {
+ s64 const l = *lp;
+
+ if ((l >= 0) ? (m > INT_FAST32_MAX - l) : (m < INT_FAST32_MIN - l))
+ return true;
+ *lp += m;
+ return false;
+}
+
+constexpr bool increment_overflow_time(time_t* tp, s64 j) {
+ /*
+ ** This is like
+ ** 'if (! (TIME_T_MIN <= *tp + j && *tp + j <= TIME_T_MAX)) ...',
+ ** except that it does the right thing even if *tp + j would overflow.
+ */
+ if (!(j < 0 ? (std::is_signed_v<time_t> ? TIME_T_MIN - j <= *tp : -1 - j < *tp)
+ : *tp <= TIME_T_MAX - j)) {
+ return true;
+ }
+ *tp += j;
+ return false;
+}
+
+CalendarTimeInternal* timesub(const time_t* timep, s64 offset, const Rule* sp,
+ CalendarTimeInternal* tmp) {
+ time_t tdays;
+ const int* ip;
+ s64 idays, rem, dayoff, dayrem;
+ time_t y;
+
+ /* Calculate the year, avoiding integer overflow even if
+ time_t is unsigned. */
+ tdays = *timep / SECSPERDAY;
+ rem = *timep % SECSPERDAY;
+ rem += offset % SECSPERDAY + 3 * SECSPERDAY;
+ dayoff = offset / SECSPERDAY + rem / SECSPERDAY - 3;
+ rem %= SECSPERDAY;
+ /* y = (EPOCH_YEAR
+ + floor((tdays + dayoff) / DAYSPERREPEAT) * YEARSPERREPEAT),
+ sans overflow. But calculate against 1570 (EPOCH_YEAR -
+ YEARSPERREPEAT) instead of against 1970 so that things work
+ for localtime values before 1970 when time_t is unsigned. */
+ dayrem = tdays % DAYSPERREPEAT;
+ dayrem += dayoff % DAYSPERREPEAT;
+ y = (EPOCH_YEAR - YEARSPERREPEAT +
+ ((1ull + dayoff / DAYSPERREPEAT + dayrem / DAYSPERREPEAT - ((dayrem % DAYSPERREPEAT) < 0) +
+ tdays / DAYSPERREPEAT) *
+ YEARSPERREPEAT));
+ /* idays = (tdays + dayoff) mod DAYSPERREPEAT, sans overflow. */
+ idays = tdays % DAYSPERREPEAT;
+ idays += dayoff % DAYSPERREPEAT + 2 * DAYSPERREPEAT;
+ idays %= DAYSPERREPEAT;
+ /* Increase Y and decrease IDAYS until IDAYS is in range for Y. */
+ while (year_lengths[isleap(y)] <= idays) {
+ s64 tdelta = idays / DAYSPERLYEAR;
+ s64 ydelta = tdelta + !tdelta;
+ time_t newy = y + ydelta;
+ int leapdays;
+ leapdays = static_cast<s32>(leaps_thru_end_of(newy - 1) - leaps_thru_end_of(y - 1));
+ idays -= ydelta * DAYSPERNYEAR;
+ idays -= leapdays;
+ y = newy;
+ }
+
+ if constexpr (!std::is_signed_v<time_t> && y < TM_YEAR_BASE) {
+ int signed_y = static_cast<s32>(y);
+ tmp->tm_year = signed_y - TM_YEAR_BASE;
+ }
+ else if ((!std::is_signed_v<time_t> || std::numeric_limits<s32>::min() + TM_YEAR_BASE <= y) &&
+ y - TM_YEAR_BASE <= std::numeric_limits<s32>::max()) {
+ tmp->tm_year = static_cast<s32>(y - TM_YEAR_BASE);
+ }
+ else {
+ // errno = EOVERFLOW;
+ return nullptr;
+ }
+
+ tmp->tm_yday = static_cast<s32>(idays);
+ /*
+ ** The "extra" mods below avoid overflow problems.
+ */
+ tmp->tm_wday = static_cast<s32>(
+ TM_WDAY_BASE + ((tmp->tm_year % DAYSPERWEEK) * (DAYSPERNYEAR % DAYSPERWEEK)) +
+ leaps_thru_end_of(y - 1) - leaps_thru_end_of(TM_YEAR_BASE - 1) + idays);
+ tmp->tm_wday %= DAYSPERWEEK;
+ if (tmp->tm_wday < 0) {
+ tmp->tm_wday += DAYSPERWEEK;
+ }
+ tmp->tm_hour = static_cast<s32>(rem / SECSPERHOUR);
+ rem %= SECSPERHOUR;
+ tmp->tm_min = static_cast<s32>(rem / SECSPERMIN);
+ tmp->tm_sec = static_cast<s32>(rem % SECSPERMIN);
+
+ ip = mon_lengths[isleap(y)].data();
+ for (tmp->tm_mon = 0; idays >= ip[tmp->tm_mon]; ++(tmp->tm_mon)) {
+ idays -= ip[tmp->tm_mon];
+ }
+ tmp->tm_mday = static_cast<s32>(idays + 1);
+ tmp->tm_isdst = 0;
+ return tmp;
+}
+
+CalendarTimeInternal* gmtsub([[maybe_unused]] Rule const* sp, time_t const* timep,
+ s64 offset, CalendarTimeInternal* tmp) {
+ CalendarTimeInternal* result;
+
+ result = timesub(timep, offset, gmtptr, tmp);
+ return result;
+}
+
+CalendarTimeInternal* localsub(Rule const* sp, time_t const* timep, s64 setname,
+ CalendarTimeInternal* const tmp) {
+ const ttinfo* ttisp;
+ int i;
+ CalendarTimeInternal* result;
+ const time_t t = *timep;
+
+ if (sp == nullptr) {
+ /* Don't bother to set tzname etc.; tzset has already done it. */
+ return gmtsub(gmtptr, timep, 0, tmp);
+ }
+ if ((sp->goback && t < sp->ats[0]) || (sp->goahead && t > sp->ats[sp->timecnt - 1])) {
+ time_t newt;
+ time_t seconds;
+ time_t years;
+
+ if (t < sp->ats[0]) {
+ seconds = sp->ats[0] - t;
+ }
+ else {
+ seconds = t - sp->ats[sp->timecnt - 1];
+ }
+ --seconds;
+
+ /* Beware integer overflow, as SECONDS might
+ be close to the maximum time_t. */
+ years = seconds / SECSPERREPEAT * YEARSPERREPEAT;
+ seconds = years * AVGSECSPERYEAR;
+ years += YEARSPERREPEAT;
+ if (t < sp->ats[0]) {
+ newt = t + seconds + SECSPERREPEAT;
+ }
+ else {
+ newt = t - seconds - SECSPERREPEAT;
+ }
+
+ if (newt < sp->ats[0] || newt > sp->ats[sp->timecnt - 1]) {
+ return nullptr; /* "cannot happen" */
+ }
+ result = localsub(sp, &newt, setname, tmp);
+ if (result) {
+ int_fast64_t newy;
+
+ newy = result->tm_year;
+ if (t < sp->ats[0]) {
+ newy -= years;
+ }
+ else {
+ newy += years;
+ }
+ if (!(std::numeric_limits<s32>::min() <= newy &&
+ newy <= std::numeric_limits<s32>::max())) {
+ return nullptr;
+ }
+ result->tm_year = static_cast<s32>(newy);
+ }
+ return result;
+ }
+ if (sp->timecnt == 0 || t < sp->ats[0]) {
+ i = sp->defaulttype;
+ }
+ else {
+ int lo = 1;
+ int hi = sp->timecnt;
+
+ while (lo < hi) {
+ int mid = (lo + hi) >> 1;
+
+ if (t < sp->ats[mid])
+ hi = mid;
+ else
+ lo = mid + 1;
+ }
+ i = sp->types[lo - 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_utoff;
+ ** timesub(&t, 0L, sp, tmp);
+ */
+ result = timesub(&t, ttisp->tt_utoff, sp, tmp);
+ if (result) {
+ result->tm_isdst = ttisp->tt_isdst;
+
+ if (ttisp->tt_desigidx > static_cast<s32>(sp->chars.size() - CHARS_EXTRA)) {
+ return nullptr;
+ }
+
+ auto num_chars_to_copy{
+ std::min(sp->chars.size() - ttisp->tt_desigidx, result->tm_zone.size()) - 1 };
+ std::strncpy(result->tm_zone.data(), &sp->chars[ttisp->tt_desigidx], num_chars_to_copy);
+ result->tm_zone[num_chars_to_copy] = '\0';
+
+ auto original_size{ std::strlen(&sp->chars[ttisp->tt_desigidx]) };
+ if (original_size > num_chars_to_copy) {
+ return nullptr;
+ }
+
+ result->tm_utoff = ttisp->tt_utoff;
+ result->time_index = i;
+ }
+ return result;
+}
+
+/*
+** Given a year, a rule, and the offset from UT at the time that rule takes
+** effect, calculate the year-relative time that rule takes effect.
+*/
+
+constexpr s64 transtime(const int year, const tzrule* const rulep,
+ const s64 offset) {
+ bool leapyear;
+ s64 value;
+ int i;
+ int d, m1, yy0, yy1, yy2, dow;
+
+ 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 = (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 = rulep->r_day * SECSPERDAY;
+ break;
+
+ case MONTH_NTH_DAY_OF_WEEK:
+ /*
+ ** Mm.n.d - nth "dth day" of month m.
+ */
+
+ /*
+ ** 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;
+ for (i = 0; i < rulep->r_mon - 1; ++i) {
+ value += mon_lengths[leapyear][i] * SECSPERDAY;
+ }
+ break;
+
+ default:
+ //UNREACHABLE();
+ break;
+ }
+
+ /*
+ ** "value" is the year-relative time of 00:00:00 UT on the day in
+ ** question. To get the year-relative time of the specified local
+ ** time on that day, add the transition time and the current offset
+ ** from UT.
+ */
+ return value + rulep->r_time + offset;
+}
+
+bool tzparse(const char* name, Rule* sp) {
+ const char* stdname{};
+ const char* dstname{};
+ s64 stdoffset;
+ s64 dstoffset;
+ char* cp;
+ ptrdiff_t stdlen;
+ ptrdiff_t dstlen{};
+ ptrdiff_t charcnt;
+ time_t atlo = TIME_T_MIN, leaplo = TIME_T_MIN;
+
+ stdname = name;
+ if (*name == '<') {
+ name++;
+ stdname = name;
+ name = getqzname(name, '>');
+ if (*name != '>') {
+ return false;
+ }
+ stdlen = name - stdname;
+ name++;
+ }
+ else {
+ name = getzname(name);
+ stdlen = name - stdname;
+ }
+ if (!(0 < stdlen && stdlen <= TZNAME_MAXIMUM)) {
+ return false;
+ }
+ name = getoffset(name, &stdoffset);
+ if (name == nullptr) {
+ return false;
+ }
+ charcnt = stdlen + 1;
+ if (charcnt > TZ_MAX_CHARS) {
+ return false;
+ }
+ if (*name != '\0') {
+ if (*name == '<') {
+ dstname = ++name;
+ name = getqzname(name, '>');
+ if (*name != '>')
+ return false;
+ dstlen = name - dstname;
+ name++;
+ }
+ else {
+ dstname = name;
+ name = getzname(name);
+ dstlen = name - dstname; /* length of DST abbr. */
+ }
+ if (!(0 < dstlen && dstlen <= TZNAME_MAXIMUM)) {
+ return false;
+ }
+ charcnt += dstlen + 1;
+ if (charcnt > TZ_MAX_CHARS) {
+ return false;
+ }
+ if (*name != '\0' && *name != ',' && *name != ';') {
+ name = getoffset(name, &dstoffset);
+ if (name == nullptr) {
+ return false;
+ }
+ }
+ else {
+ dstoffset = stdoffset - SECSPERHOUR;
+ }
+ if (*name == '\0') {
+ name = TZDEFRULESTRING;
+ }
+ if (*name == ',' || *name == ';') {
+ struct tzrule start;
+ struct tzrule end;
+ int year;
+ int timecnt;
+ time_t janfirst;
+ s64 janoffset = 0;
+ int yearbeg, yearlim;
+
+ ++name;
+ if ((name = getrule(name, &start)) == nullptr) {
+ return false;
+ }
+ if (*name++ != ',') {
+ return false;
+ }
+ if ((name = getrule(name, &end)) == nullptr) {
+ return false;
+ }
+ if (*name != '\0') {
+ return false;
+ }
+ sp->typecnt = 2; /* standard time and DST */
+ /*
+ ** Two transitions per year, from EPOCH_YEAR forward.
+ */
+ init_ttinfo(&sp->ttis[0], -stdoffset, false, 0);
+ init_ttinfo(&sp->ttis[1], -dstoffset, true, static_cast<s32>(stdlen + 1));
+ sp->defaulttype = 0;
+ timecnt = 0;
+ janfirst = 0;
+ yearbeg = EPOCH_YEAR;
+
+ do {
+ s64 yearsecs = year_lengths[isleap(yearbeg - 1)] * SECSPERDAY;
+ yearbeg--;
+ if (increment_overflow_time(&janfirst, -yearsecs)) {
+ janoffset = -yearsecs;
+ break;
+ }
+ } while (atlo < janfirst && EPOCH_YEAR - YEARSPERREPEAT / 2 < yearbeg);
+
+ while (true) {
+ s64 yearsecs = year_lengths[isleap(yearbeg)] * SECSPERDAY;
+ int yearbeg1 = yearbeg;
+ time_t janfirst1 = janfirst;
+ if (increment_overflow_time(&janfirst1, yearsecs) ||
+ increment_overflow(&yearbeg1, 1) || atlo <= janfirst1) {
+ break;
+ }
+ yearbeg = yearbeg1;
+ janfirst = janfirst1;
+ }
+
+ yearlim = yearbeg;
+ if (increment_overflow(&yearlim, YEARSPERREPEAT + 1)) {
+ yearlim = INT_MAX;
+ }
+ for (year = yearbeg; year < yearlim; year++) {
+ s64 starttime = transtime(year, &start, stdoffset),
+ endtime = transtime(year, &end, dstoffset);
+ s64 yearsecs = (year_lengths[isleap(year)] * SECSPERDAY);
+ bool reversed = endtime < starttime;
+ if (reversed) {
+ s64 swap = starttime;
+ starttime = endtime;
+ endtime = swap;
+ }
+ if (reversed || (starttime < endtime && endtime - starttime < yearsecs)) {
+ if (TZ_MAX_TIMES - 2 < timecnt) {
+ break;
+ }
+ sp->ats[timecnt] = janfirst;
+ if (!increment_overflow_time(reinterpret_cast<time_t*>(&sp->ats[timecnt]), janoffset + starttime) &&
+ atlo <= sp->ats[timecnt]) {
+ sp->types[timecnt++] = !reversed;
+ }
+ sp->ats[timecnt] = janfirst;
+ if (!increment_overflow_time(reinterpret_cast<time_t*>(&sp->ats[timecnt]), janoffset + endtime) &&
+ atlo <= sp->ats[timecnt]) {
+ sp->types[timecnt++] = reversed;
+ }
+ }
+ if (endtime < leaplo) {
+ yearlim = year;
+ if (increment_overflow(&yearlim, YEARSPERREPEAT + 1)) {
+ yearlim = INT_MAX;
+ }
+ }
+ if (increment_overflow_time(&janfirst, janoffset + yearsecs)) {
+ break;
+ }
+ janoffset = 0;
+ }
+ sp->timecnt = timecnt;
+ if (!timecnt) {
+ sp->ttis[0] = sp->ttis[1];
+ sp->typecnt = 1; /* Perpetual DST. */
+ }
+ else if (YEARSPERREPEAT < year - yearbeg) {
+ sp->goback = sp->goahead = true;
+ }
+ }
+ else {
+ s64 theirstdoffset;
+ s64 theirdstoffset;
+ s64 theiroffset;
+ bool isdst;
+ int i;
+ int j;
+
+ if (*name != '\0') {
+ return false;
+ }
+ /*
+ ** Initial values of theirstdoffset and theirdstoffset.
+ */
+ theirstdoffset = 0;
+ for (i = 0; i < sp->timecnt; ++i) {
+ j = sp->types[i];
+ if (!sp->ttis[j].tt_isdst) {
+ theirstdoffset = -sp->ttis[j].tt_utoff;
+ break;
+ }
+ }
+ theirdstoffset = 0;
+ for (i = 0; i < sp->timecnt; ++i) {
+ j = sp->types[i];
+ if (sp->ttis[j].tt_isdst) {
+ theirdstoffset = -sp->ttis[j].tt_utoff;
+ break;
+ }
+ }
+ /*
+ ** Initially we're assumed to be in standard time.
+ */
+ isdst = false;
+ /*
+ ** Now juggle transition times and types
+ ** tracking offsets as you do.
+ */
+ for (i = 0; i < sp->timecnt; ++i) {
+ j = sp->types[i];
+ sp->types[i] = sp->ttis[j].tt_isdst;
+ if (sp->ttis[j].tt_ttisut) {
+ /* No adjustment to transition time */
+ }
+ else {
+ /*
+ ** If daylight saving time is in
+ ** effect, and the transition time was
+ ** not specified as standard time, add
+ ** the daylight saving time offset to
+ ** the transition time; otherwise, add
+ ** the standard time offset to the
+ ** transition time.
+ */
+ /*
+ ** Transitions from DST to DDST
+ ** will effectively disappear since
+ ** POSIX provides for only one DST
+ ** offset.
+ */
+ if (isdst && !sp->ttis[j].tt_ttisstd) {
+ sp->ats[i] += dstoffset - theirdstoffset;
+ }
+ else {
+ sp->ats[i] += stdoffset - theirstdoffset;
+ }
+ }
+ theiroffset = -sp->ttis[j].tt_utoff;
+ if (sp->ttis[j].tt_isdst) {
+ theirdstoffset = theiroffset;
+ }
+ else {
+ theirstdoffset = theiroffset;
+ }
+ }
+ /*
+ ** Finally, fill in ttis.
+ */
+ init_ttinfo(&sp->ttis[0], -stdoffset, false, 0);
+ init_ttinfo(&sp->ttis[1], -dstoffset, true, static_cast<s32>(stdlen + 1));
+ sp->typecnt = 2;
+ sp->defaulttype = 0;
+ }
+ }
+ else {
+ dstlen = 0;
+ sp->typecnt = 1; /* only standard time */
+ sp->timecnt = 0;
+ init_ttinfo(&sp->ttis[0], -stdoffset, false, 0);
+ sp->defaulttype = 0;
+ }
+ sp->charcnt = static_cast<s32>(charcnt);
+ cp = &sp->chars[0];
+ memcpy(cp, stdname, stdlen);
+ cp += stdlen;
+ *cp++ = '\0';
+ if (dstlen != 0) {
+ memcpy(cp, dstname, dstlen);
+ *(cp + dstlen) = '\0';
+ }
+ return true;
+}
+
+int tzloadbody(Rule* sp, local_storage& local_storage) {
+ int i;
+ int stored;
+ size_t nread{ local_storage.binary.size_bytes() };
+ int tzheadsize = sizeof(struct TzifHeader);
+ TzifHeader header{};
+
+ //ASSERT(local_storage.binary.size_bytes() >= sizeof(TzifHeader));
+ std::memcpy(&header, local_storage.binary.data(), sizeof(TzifHeader));
+
+ sp->goback = sp->goahead = false;
+
+ for (stored = 8; stored <= 8; stored *= 2) {
+ s64 datablock_size;
+ s32 ttisstdcnt = detzcode(header.tzh_ttisstdcnt.data());
+ s32 ttisutcnt = detzcode(header.tzh_ttisutcnt.data());
+ s32 leapcnt = detzcode(header.tzh_leapcnt.data());
+ s32 timecnt = detzcode(header.tzh_timecnt.data());
+ s32 typecnt = detzcode(header.tzh_typecnt.data());
+ s32 charcnt = detzcode(header.tzh_charcnt.data());
+ /* Although tzfile(5) currently requires typecnt to be nonzero,
+ support future formats that may allow zero typecnt
+ in files that have a TZ string and no transitions. */
+ if (!(0 <= leapcnt && leapcnt < TZ_MAX_LEAPS && 0 <= typecnt && typecnt < TZ_MAX_TYPES &&
+ 0 <= timecnt && timecnt < TZ_MAX_TIMES && 0 <= charcnt && charcnt < TZ_MAX_CHARS &&
+ 0 <= ttisstdcnt && ttisstdcnt < TZ_MAX_TYPES && 0 <= ttisutcnt &&
+ ttisutcnt < TZ_MAX_TYPES)) {
+ return EINVAL;
+ }
+ datablock_size = (timecnt * stored /* ats */
+ + timecnt /* types */
+ + typecnt * 6 /* ttinfos */
+ + charcnt /* chars */
+ + leapcnt * (stored + 4) /* lsinfos */
+ + ttisstdcnt /* ttisstds */
+ + ttisutcnt); /* ttisuts */
+ if (static_cast<s32>(local_storage.binary.size_bytes()) < tzheadsize + datablock_size) {
+ return EINVAL;
+ }
+ if (!((ttisstdcnt == typecnt || ttisstdcnt == 0) &&
+ (ttisutcnt == typecnt || ttisutcnt == 0))) {
+ return EINVAL;
+ }
+
+ char const* p = (const char*)local_storage.binary.data() + tzheadsize;
+
+ sp->timecnt = timecnt;
+ sp->typecnt = typecnt;
+ sp->charcnt = charcnt;
+
+ /* Read transitions, discarding those out of time_t range.
+ But pretend the last transition before TIME_T_MIN
+ occurred at TIME_T_MIN. */
+ timecnt = 0;
+ for (i = 0; i < sp->timecnt; ++i) {
+ int_fast64_t at = stored == 4 ? detzcode(p) : detzcode64(p);
+ sp->types[i] = at <= TIME_T_MAX;
+ if (sp->types[i]) {
+ time_t attime =
+ ((std::is_signed_v<time_t> ? at < TIME_T_MIN : at < 0) ? TIME_T_MIN : at);
+ if (timecnt && attime <= sp->ats[timecnt - 1]) {
+ if (attime < sp->ats[timecnt - 1])
+ return EINVAL;
+ sp->types[i - 1] = 0;
+ timecnt--;
+ }
+ sp->ats[timecnt++] = attime;
+ }
+ p += stored;
+ }
+
+ timecnt = 0;
+ for (i = 0; i < sp->timecnt; ++i) {
+ unsigned char typ = *p++;
+ if (sp->typecnt <= typ) {
+ return EINVAL;
+ }
+ if (sp->types[i]) {
+ sp->types[timecnt++] = typ;
+ }
+ }
+ sp->timecnt = timecnt;
+ for (i = 0; i < sp->typecnt; ++i) {
+ struct ttinfo* ttisp;
+ unsigned char isdst, desigidx;
+
+ ttisp = &sp->ttis[i];
+ ttisp->tt_utoff = detzcode(p);
+ p += 4;
+ isdst = *p++;
+ if (!(isdst < 2)) {
+ return EINVAL;
+ }
+ ttisp->tt_isdst = isdst != 0;
+ desigidx = *p++;
+ if (!(desigidx < sp->charcnt)) {
+ return EINVAL;
+ }
+ ttisp->tt_desigidx = desigidx;
+ }
+ for (i = 0; i < sp->charcnt; ++i) {
+ sp->chars[i] = *p++;
+ }
+ /* Ensure '\0'-terminated, and make it safe to call
+ ttunspecified later. */
+ memset(&sp->chars[i], 0, CHARS_EXTRA);
+
+ for (i = 0; i < sp->typecnt; ++i) {
+ struct ttinfo* ttisp;
+
+ ttisp = &sp->ttis[i];
+ if (ttisstdcnt == 0) {
+ ttisp->tt_ttisstd = false;
+ }
+ else {
+ if (*(bool*)p != true && *(bool*)p != false) {
+ return EINVAL;
+ }
+ ttisp->tt_ttisstd = *(bool*)p++;
+ }
+ }
+ for (i = 0; i < sp->typecnt; ++i) {
+ struct ttinfo* ttisp;
+
+ ttisp = &sp->ttis[i];
+ if (ttisutcnt == 0) {
+ ttisp->tt_ttisut = false;
+ }
+ else {
+ if (*(bool*)p != true && *(bool*)p != false) {
+ return EINVAL;
+ }
+ ttisp->tt_ttisut = *(bool*)p++;
+ }
+ }
+
+ nread += (ptrdiff_t)local_storage.binary.data() - (ptrdiff_t)p;
+ if (nread < 0) {
+ return EINVAL;
+ }
+ }
+
+ std::array<char, 256> buf{};
+ if (nread > buf.size()) {
+ //ASSERT(false);
+ return EINVAL;
+ }
+ memmove(buf.data(), &local_storage.binary[local_storage.binary.size_bytes() - nread], nread);
+
+ if (nread > 2 && buf[0] == '\n' && buf[nread - 1] == '\n' && sp->typecnt + 2 <= TZ_MAX_TYPES) {
+ Rule* ts = &local_storage.state;
+
+ buf[nread - 1] = '\0';
+ if (tzparse(&buf[1], ts) && local_storage.state.typecnt == 2) {
+
+ /* Attempt to reuse existing abbreviations.
+ Without this, America/Anchorage would be right on
+ the edge after 2037 when TZ_MAX_CHARS is 50, as
+ sp->charcnt equals 40 (for LMT AST AWT APT AHST
+ AHDT YST AKDT AKST) and ts->charcnt equals 10
+ (for AKST AKDT). Reusing means sp->charcnt can
+ stay 40 in this example. */
+ int gotabbr = 0;
+ int charcnt = sp->charcnt;
+ for (i = 0; i < ts->typecnt; i++) {
+ char* tsabbr = &ts->chars[ts->ttis[i].tt_desigidx];
+ int j;
+ for (j = 0; j < charcnt; j++)
+ if (strcmp(&sp->chars[j], tsabbr) == 0) {
+ ts->ttis[i].tt_desigidx = j;
+ gotabbr++;
+ break;
+ }
+ if (!(j < charcnt)) {
+ int tsabbrlen = static_cast<s32>(strlen(tsabbr));
+ if (j + tsabbrlen < TZ_MAX_CHARS) {
+ strcpy(&sp->chars[j], tsabbr);
+ charcnt = j + tsabbrlen + 1;
+ ts->ttis[i].tt_desigidx = j;
+ gotabbr++;
+ }
+ }
+ }
+ if (gotabbr == ts->typecnt) {
+ sp->charcnt = charcnt;
+
+ /* Ignore any trailing, no-op transitions generated
+ by zic as they don't help here and can run afoul
+ of bugs in zic 2016j or earlier. */
+ while (1 < sp->timecnt &&
+ (sp->types[sp->timecnt - 1] == sp->types[sp->timecnt - 2])) {
+ sp->timecnt--;
+ }
+
+ for (i = 0; i < ts->timecnt && sp->timecnt < TZ_MAX_TIMES; i++) {
+ time_t t = ts->ats[i];
+ if (0 < sp->timecnt && t <= sp->ats[sp->timecnt - 1]) {
+ continue;
+ }
+ sp->ats[sp->timecnt] = t;
+ sp->types[sp->timecnt] = static_cast<u8>(sp->typecnt + ts->types[i]);
+ sp->timecnt++;
+ }
+ for (i = 0; i < ts->typecnt; i++) {
+ sp->ttis[sp->typecnt++] = ts->ttis[i];
+ }
+ }
+ }
+ }
+ if (sp->typecnt == 0) {
+ return EINVAL;
+ }
+
+ if (sp->timecnt > 1) {
+ if (sp->ats[0] <= TIME_T_MAX - SECSPERREPEAT) {
+ time_t repeatat = sp->ats[0] + SECSPERREPEAT;
+ int repeattype = sp->types[0];
+ for (i = 1; i < sp->timecnt; ++i) {
+ if (sp->ats[i] == repeatat && typesequiv(sp, sp->types[i], repeattype)) {
+ sp->goback = true;
+ break;
+ }
+ }
+ }
+ if (TIME_T_MIN + SECSPERREPEAT <= sp->ats[sp->timecnt - 1]) {
+ time_t repeatat = sp->ats[sp->timecnt - 1] - SECSPERREPEAT;
+ int repeattype = sp->types[sp->timecnt - 1];
+ for (i = sp->timecnt - 2; i >= 0; --i) {
+ if (sp->ats[i] == repeatat && typesequiv(sp, sp->types[i], repeattype)) {
+ sp->goahead = true;
+ break;
+ }
+ }
+ }
+ }
+
+ /* Infer sp->defaulttype from the data. Although this default
+ type is always zero for data from recent tzdb releases,
+ things are trickier for data from tzdb 2018e or earlier.
+
+ The first set of heuristics work around bugs in 32-bit data
+ generated by tzdb 2013c or earlier. The workaround is for
+ zones like Australia/Macquarie where timestamps before the
+ first transition have a time type that is not the earliest
+ standard-time type. See:
+ https://mm.icann.org/pipermail/tz/2013-May/019368.html */
+ /*
+ ** If type 0 does not specify local time, or is unused in transitions,
+ ** it's the type to use for early times.
+ */
+ for (i = 0; i < sp->timecnt; ++i) {
+ if (sp->types[i] == 0) {
+ break;
+ }
+ }
+ i = i < sp->timecnt && !ttunspecified(sp, 0) ? -1 : 0;
+ /*
+ ** Absent the above,
+ ** if there are transition times
+ ** and the first transition is to a daylight time
+ ** find the standard type less than and closest to
+ ** the type of the first transition.
+ */
+ if (i < 0 && sp->timecnt > 0 && sp->ttis[sp->types[0]].tt_isdst) {
+ i = sp->types[0];
+ while (--i >= 0) {
+ if (!sp->ttis[i].tt_isdst) {
+ break;
+ }
+ }
+ }
+ /* The next heuristics are for data generated by tzdb 2018e or
+ earlier, for zones like EST5EDT where the first transition
+ is to DST. */
+ /*
+ ** If no result yet, find the first standard type.
+ ** If there is none, punt to type zero.
+ */
+ if (i < 0) {
+ i = 0;
+ while (sp->ttis[i].tt_isdst) {
+ if (++i >= sp->typecnt) {
+ i = 0;
+ break;
+ }
+ }
+ }
+ /* A simple 'sp->defaulttype = 0;' would suffice here if we
+ didn't have to worry about 2018e-or-earlier data. Even
+ simpler would be to remove the defaulttype member and just
+ use 0 in its place. */
+ sp->defaulttype = i;
+
+ return 0;
+}
+
+constexpr int tmcomp(const CalendarTimeInternal* const atmp,
+ const CalendarTimeInternal* const btmp) {
+ int result;
+
+ if (atmp->tm_year != btmp->tm_year) {
+ return atmp->tm_year < btmp->tm_year ? -1 : 1;
+ }
+ if ((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;
+}
+
+/* Copy to *DEST from *SRC. Copy only the members needed for mktime,
+ as other members might not be initialized. */
+constexpr void mktmcpy(struct CalendarTimeInternal* dest, struct CalendarTimeInternal const* src) {
+ dest->tm_sec = src->tm_sec;
+ dest->tm_min = src->tm_min;
+ dest->tm_hour = src->tm_hour;
+ dest->tm_mday = src->tm_mday;
+ dest->tm_mon = src->tm_mon;
+ dest->tm_year = src->tm_year;
+ dest->tm_isdst = src->tm_isdst;
+ dest->tm_zone = src->tm_zone;
+ dest->tm_utoff = src->tm_utoff;
+ dest->time_index = src->time_index;
+}
+
+constexpr bool normalize_overflow(int* const tensptr, int* const unitsptr, const int base) {
+ int tensdelta;
+
+ tensdelta = (*unitsptr >= 0) ? (*unitsptr / base) : (-1 - (-1 - *unitsptr) / base);
+ *unitsptr -= tensdelta * base;
+ return increment_overflow(tensptr, tensdelta);
+}
+
+constexpr bool normalize_overflow32(s64* tensptr, int* unitsptr, int base) {
+ int tensdelta;
+
+ tensdelta = (*unitsptr >= 0) ? (*unitsptr / base) : (-1 - (-1 - *unitsptr) / base);
+ *unitsptr -= tensdelta * base;
+ return increment_overflow32(tensptr, tensdelta);
+}
+
+int time2sub(time_t* out_time, CalendarTimeInternal* const tmp,
+ CalendarTimeInternal* (*funcp)(Rule const*, time_t const*, s64,
+ CalendarTimeInternal*),
+ Rule const* sp, const s64 offset, bool* okayp, bool do_norm_secs) {
+ int dir;
+ int i, j;
+ int saved_seconds;
+ s64 li;
+ time_t lo;
+ time_t hi;
+ s64 y;
+ time_t newt;
+ time_t t;
+ CalendarTimeInternal yourtm, mytm;
+
+ *okayp = false;
+ mktmcpy(&yourtm, tmp);
+
+ if (do_norm_secs) {
+ if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec, SECSPERMIN)) {
+ return 1;
+ }
+ }
+ if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) {
+ return 1;
+ }
+ if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) {
+ return 1;
+ }
+ y = yourtm.tm_year;
+ if (normalize_overflow32(&y, &yourtm.tm_mon, MONSPERYEAR)) {
+ return 1;
+ }
+ /*
+ ** Turn y into an actual year number for now.
+ ** It is converted back to an offset from TM_YEAR_BASE later.
+ */
+ if (increment_overflow32(&y, TM_YEAR_BASE)) {
+ return 1;
+ }
+ while (yourtm.tm_mday <= 0) {
+ if (increment_overflow32(&y, -1)) {
+ return 1;
+ }
+ li = y + (1 < yourtm.tm_mon);
+ yourtm.tm_mday += year_lengths[isleap(li)];
+ }
+ while (yourtm.tm_mday > DAYSPERLYEAR) {
+ li = y + (1 < yourtm.tm_mon);
+ yourtm.tm_mday -= year_lengths[isleap(li)];
+ if (increment_overflow32(&y, 1)) {
+ return 1;
+ }
+ }
+ for (;;) {
+ i = mon_lengths[isleap(y)][yourtm.tm_mon];
+ if (yourtm.tm_mday <= i) {
+ break;
+ }
+ yourtm.tm_mday -= i;
+ if (++yourtm.tm_mon >= MONSPERYEAR) {
+ yourtm.tm_mon = 0;
+ if (increment_overflow32(&y, 1)) {
+ return 1;
+ }
+ }
+ }
+
+ if (increment_overflow32(&y, -TM_YEAR_BASE)) {
+ return 1;
+ }
+ if (!(INT_MIN <= y && y <= INT_MAX)) {
+ return 1;
+ }
+ yourtm.tm_year = static_cast<s32>(y);
+
+ if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN) {
+ saved_seconds = 0;
+ }
+ else if (yourtm.tm_year < EPOCH_YEAR - TM_YEAR_BASE) {
+ /*
+ ** 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 1;
+ }
+ saved_seconds = yourtm.tm_sec;
+ yourtm.tm_sec = SECSPERMIN - 1;
+ }
+ else {
+ saved_seconds = yourtm.tm_sec;
+ yourtm.tm_sec = 0;
+ }
+ /*
+ ** Do a binary search (this works whatever time_t's type is).
+ */
+ lo = TIME_T_MIN;
+ hi = TIME_T_MAX;
+ for (;;) {
+ t = lo / 2 + hi / 2;
+ if (t < lo) {
+ t = lo;
+ }
+ else if (t > hi) {
+ t = hi;
+ }
+ if (!funcp(sp, &t, offset, &mytm)) {
+ /*
+ ** Assume that t is too extreme to be represented in
+ ** a struct tm; arrange things so that it is less
+ ** extreme on the next pass.
+ */
+ dir = (t > 0) ? 1 : -1;
+ }
+ else {
+ dir = tmcomp(&mytm, &yourtm);
+ }
+ if (dir != 0) {
+ if (t == lo) {
+ if (t == TIME_T_MAX) {
+ return 2;
+ }
+ ++t;
+ ++lo;
+ }
+ else if (t == hi) {
+ if (t == TIME_T_MIN) {
+ return 2;
+ }
+ --t;
+ --hi;
+ }
+ if (lo > hi) {
+ return 2;
+ }
+ if (dir > 0) {
+ hi = t;
+ }
+ else {
+ lo = t;
+ }
+ 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.
+ */
+ if (sp == nullptr) {
+ return 2;
+ }
+ for (i = sp->typecnt - 1; i >= 0; --i) {
+ if (sp->ttis[i].tt_isdst != static_cast<bool>(yourtm.tm_isdst)) {
+ continue;
+ }
+ for (j = sp->typecnt - 1; j >= 0; --j) {
+ if (sp->ttis[j].tt_isdst == static_cast<bool>(yourtm.tm_isdst)) {
+ continue;
+ }
+ if (ttunspecified(sp, j)) {
+ continue;
+ }
+ newt = (t + sp->ttis[j].tt_utoff - sp->ttis[i].tt_utoff);
+ if (!funcp(sp, &newt, offset, &mytm)) {
+ continue;
+ }
+ if (tmcomp(&mytm, &yourtm) != 0) {
+ continue;
+ }
+ if (mytm.tm_isdst != yourtm.tm_isdst) {
+ continue;
+ }
+ /*
+ ** We have a match.
+ */
+ t = newt;
+ goto label;
+ }
+ }
+ return 2;
+ }
+label:
+ newt = t + saved_seconds;
+ t = newt;
+ if (funcp(sp, &t, offset, tmp) || *okayp) {
+ *okayp = true;
+ *out_time = t;
+ return 0;
+ }
+ return 2;
+}
+
+int time2(time_t* out_time, struct CalendarTimeInternal* const tmp,
+ struct CalendarTimeInternal* (*funcp)(struct Rule const*, time_t const*, s64,
+ struct CalendarTimeInternal*),
+ struct Rule const* sp, const s64 offset, bool* okayp) {
+ int res;
+
+ /*
+ ** First try without normalization of seconds
+ ** (in case tm_sec contains a value associated with a leap second).
+ ** If that fails, try with normalization of seconds.
+ */
+ res = time2sub(out_time, tmp, funcp, sp, offset, okayp, false);
+ return *okayp ? res : time2sub(out_time, tmp, funcp, sp, offset, okayp, true);
+}
+
+int time1(time_t* out_time, CalendarTimeInternal* const tmp,
+ CalendarTimeInternal* (*funcp)(Rule const*, time_t const*, s64,
+ CalendarTimeInternal*),
+ Rule const* sp, const s64 offset) {
+ int samei, otheri;
+ int sameind, otherind;
+ int i;
+ int nseen;
+ char seen[TZ_MAX_TYPES];
+ unsigned char types[TZ_MAX_TYPES];
+ bool okay;
+
+ if (tmp->tm_isdst > 1) {
+ tmp->tm_isdst = 1;
+ }
+ auto res = time2(out_time, tmp, funcp, sp, offset, &okay);
+ if (res == 0) {
+ return res;
+ }
+ if (tmp->tm_isdst < 0) {
+ return res;
+ }
+ /*
+ ** 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.
+ */
+ for (i = 0; i < sp->typecnt; ++i) {
+ seen[i] = false;
+ }
+
+ if (sp->timecnt < 1) {
+ return 2;
+ }
+
+ nseen = 0;
+ for (i = sp->timecnt - 1; i >= 0; --i) {
+ if (!seen[sp->types[i]] && !ttunspecified(sp, sp->types[i])) {
+ seen[sp->types[i]] = true;
+ types[nseen++] = sp->types[i];
+ }
+ }
+
+ if (nseen < 1) {
+ return 2;
+ }
+
+ for (sameind = 0; sameind < nseen; ++sameind) {
+ samei = types[sameind];
+ if (sp->ttis[samei].tt_isdst != static_cast<bool>(tmp->tm_isdst)) {
+ continue;
+ }
+ for (otherind = 0; otherind < nseen; ++otherind) {
+ otheri = types[otherind];
+ if (sp->ttis[otheri].tt_isdst == static_cast<bool>(tmp->tm_isdst)) {
+ continue;
+ }
+ tmp->tm_sec += (sp->ttis[otheri].tt_utoff - sp->ttis[samei].tt_utoff);
+ tmp->tm_isdst = !tmp->tm_isdst;
+ res = time2(out_time, tmp, funcp, sp, offset, &okay);
+ if (res == 0) {
+ return res;
+ }
+ tmp->tm_sec -= (sp->ttis[otheri].tt_utoff - sp->ttis[samei].tt_utoff);
+ tmp->tm_isdst = !tmp->tm_isdst;
+ }
+ }
+ return 2;
+}
+
+} // namespace
+
+s32 ParseTimeZoneBinary(Rule& out_rule, std::span<const u8> binary) {
+ tzloadbody_local_storage.binary = binary;
+ if (tzloadbody(&out_rule, tzloadbody_local_storage)) {
+ return 3;
+ }
+ return 0;
+}
+
+bool localtime_rz(CalendarTimeInternal* tmp, Rule* sp, time_t* timep) {
+ return localsub(sp, timep, 0, tmp) == nullptr;
+}
+
+u32 mktime_tzname(time_t* out_time, Rule* sp, CalendarTimeInternal* tmp) {
+ return time1(out_time, tmp, localsub, sp, 0);
+}
+
+} // namespace Tz