From 1285ca4b4f06e40ca0238bde7197e0cb3648a451 Mon Sep 17 00:00:00 2001 From: Abseil Team Date: Tue, 6 Jun 2023 11:23:59 -0700 Subject: Import of CCTZ from GitHub. PiperOrigin-RevId: 538241594 Change-Id: Ie6f0d913bcf07dea2f33e47198ba952b3800d70e --- absl/time/internal/cctz/src/time_zone_if.cc | 2 + absl/time/internal/cctz/src/time_zone_libc.cc | 61 ++++++++++++---------- .../internal/cctz/src/time_zone_lookup_test.cc | 21 +++++--- 3 files changed, 49 insertions(+), 35 deletions(-) (limited to 'absl/time') diff --git a/absl/time/internal/cctz/src/time_zone_if.cc b/absl/time/internal/cctz/src/time_zone_if.cc index 0319b2f9..1d44dde7 100644 --- a/absl/time/internal/cctz/src/time_zone_if.cc +++ b/absl/time/internal/cctz/src/time_zone_if.cc @@ -26,6 +26,8 @@ namespace cctz { std::unique_ptr TimeZoneIf::Load(const std::string& name) { // Support "libc:localtime" and "libc:*" to access the legacy // localtime and UTC support respectively from the C library. + // NOTE: The "libc:*" zones are internal, test-only interfaces, and + // are subject to change/removal without notice. Do not use them. if (name.compare(0, 5, "libc:") == 0) { return std::unique_ptr(new TimeZoneLibC(name.substr(5))); } diff --git a/absl/time/internal/cctz/src/time_zone_libc.cc b/absl/time/internal/cctz/src/time_zone_libc.cc index 887dd097..af9f063e 100644 --- a/absl/time/internal/cctz/src/time_zone_libc.cc +++ b/absl/time/internal/cctz/src/time_zone_libc.cc @@ -125,31 +125,30 @@ inline std::tm* local_time(const std::time_t* timep, std::tm* result) { #endif } -// Converts a civil second and "dst" flag into a time_t and UTC offset. +// Converts a civil second and "dst" flag into a time_t and a struct tm. // Returns false if time_t cannot represent the requested civil second. // Caller must have already checked that cs.year() will fit into a tm_year. -bool make_time(const civil_second& cs, int is_dst, std::time_t* t, int* off) { - std::tm tm; - tm.tm_year = static_cast(cs.year() - year_t{1900}); - tm.tm_mon = cs.month() - 1; - tm.tm_mday = cs.day(); - tm.tm_hour = cs.hour(); - tm.tm_min = cs.minute(); - tm.tm_sec = cs.second(); - tm.tm_isdst = is_dst; - *t = std::mktime(&tm); +bool make_time(const civil_second& cs, int is_dst, std::time_t* t, + std::tm* tm) { + tm->tm_year = static_cast(cs.year() - year_t{1900}); + tm->tm_mon = cs.month() - 1; + tm->tm_mday = cs.day(); + tm->tm_hour = cs.hour(); + tm->tm_min = cs.minute(); + tm->tm_sec = cs.second(); + tm->tm_isdst = is_dst; + *t = std::mktime(tm); if (*t == std::time_t{-1}) { std::tm tm2; const std::tm* tmp = local_time(t, &tm2); - if (tmp == nullptr || tmp->tm_year != tm.tm_year || - tmp->tm_mon != tm.tm_mon || tmp->tm_mday != tm.tm_mday || - tmp->tm_hour != tm.tm_hour || tmp->tm_min != tm.tm_min || - tmp->tm_sec != tm.tm_sec) { + if (tmp == nullptr || tmp->tm_year != tm->tm_year || + tmp->tm_mon != tm->tm_mon || tmp->tm_mday != tm->tm_mday || + tmp->tm_hour != tm->tm_hour || tmp->tm_min != tm->tm_min || + tmp->tm_sec != tm->tm_sec) { // A true error (not just one second before the epoch). return false; } } - *off = static_cast(tm_gmtoff(tm)); return true; } @@ -254,33 +253,37 @@ time_zone::civil_lookup TimeZoneLibC::MakeTime(const civil_second& cs) const { // We probe with "is_dst" values of 0 and 1 to try to distinguish unique // civil seconds from skipped or repeated ones. This is not always possible // however, as the "dst" flag does not change over some offset transitions. - // We are also subject to the vagaries of mktime() implementations. + // We are also subject to the vagaries of mktime() implementations. For + // example, some implementations treat "tm_isdst" as a demand (useless), + // and some as a disambiguator (useful). std::time_t t0, t1; - int offset0, offset1; - if (make_time(cs, 0, &t0, &offset0) && make_time(cs, 1, &t1, &offset1)) { - if (t0 == t1) { + std::tm tm0, tm1; + if (make_time(cs, 0, &t0, &tm0) && make_time(cs, 1, &t1, &tm1)) { + if (tm0.tm_isdst == tm1.tm_isdst) { // The civil time was singular (pre == trans == post). - const time_point tp = FromUnixSeconds(t0); + const time_point tp = FromUnixSeconds(tm0.tm_isdst ? t1 : t0); return {time_zone::civil_lookup::UNIQUE, tp, tp, tp}; } - if (t0 > t1) { + int offset = tm_gmtoff(tm0); + if (t0 < t1) { // negative DST std::swap(t0, t1); - std::swap(offset0, offset1); + offset = tm_gmtoff(tm1); } - const std::time_t tt = find_trans(t0, t1, offset1); + + const std::time_t tt = find_trans(t1, t0, offset); const time_point trans = FromUnixSeconds(tt); - if (offset0 < offset1) { + if (tm0.tm_isdst) { // The civil time did not exist (pre >= trans > post). - const time_point pre = FromUnixSeconds(t1); - const time_point post = FromUnixSeconds(t0); + const time_point pre = FromUnixSeconds(t0); + const time_point post = FromUnixSeconds(t1); return {time_zone::civil_lookup::SKIPPED, pre, trans, post}; } // The civil time was ambiguous (pre < trans <= post). - const time_point pre = FromUnixSeconds(t0); - const time_point post = FromUnixSeconds(t1); + const time_point pre = FromUnixSeconds(t1); + const time_point post = FromUnixSeconds(t0); return {time_zone::civil_lookup::REPEATED, pre, trans, post}; } diff --git a/absl/time/internal/cctz/src/time_zone_lookup_test.cc b/absl/time/internal/cctz/src/time_zone_lookup_test.cc index 4b093b37..38f10f48 100644 --- a/absl/time/internal/cctz/src/time_zone_lookup_test.cc +++ b/absl/time/internal/cctz/src/time_zone_lookup_test.cc @@ -1034,16 +1034,16 @@ TEST(MakeTime, SysSecondsLimits) { const time_zone cut = LoadZone("libc:UTC"); const year_t max_tm_year = year_t{std::numeric_limits::max()} + 1900; tp = convert(civil_second(max_tm_year, 12, 31, 23, 59, 59), cut); -#if defined(__FreeBSD__) || defined(__OpenBSD__) - // The BSD gmtime_r() fails on extreme positive tm_year values. +#if defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__EMSCRIPTEN__) + // Some gmtime_r() impls fail on extreme positive values. #else EXPECT_EQ("2147485547-12-31T23:59:59+00:00", absl::time_internal::cctz::format(RFC3339, tp, cut)); #endif const year_t min_tm_year = year_t{std::numeric_limits::min()} + 1900; tp = convert(civil_second(min_tm_year, 1, 1, 0, 0, 0), cut); -#if defined(__Fuchsia__) - // Fuchsia's gmtime_r() fails on extreme negative values (fxbug.dev/78527). +#if defined(__Fuchsia__) || defined(__EMSCRIPTEN__) + // Some gmtime_r() impls fail on extreme negative values (fxbug.dev/78527). #else EXPECT_EQ("-2147481748-01-01T00:00:00+00:00", absl::time_internal::cctz::format(RFC3339, tp, cut)); @@ -1072,7 +1072,7 @@ TEST(MakeTime, LocalTimeLibC) { tp = zi.lookup(transition.to).trans) { const auto fcl = zi.lookup(transition.from); const auto tcl = zi.lookup(transition.to); - civil_second cs; // compare cs in zi and lc + civil_second cs, us; // compare cs and us in zi and lc if (fcl.kind == time_zone::civil_lookup::UNIQUE) { if (tcl.kind == time_zone::civil_lookup::UNIQUE) { // Both unique; must be an is_dst or abbr change. @@ -1088,12 +1088,14 @@ TEST(MakeTime, LocalTimeLibC) { } ASSERT_EQ(time_zone::civil_lookup::REPEATED, tcl.kind); cs = transition.to; + us = transition.from; } else { ASSERT_EQ(time_zone::civil_lookup::UNIQUE, tcl.kind); ASSERT_EQ(time_zone::civil_lookup::SKIPPED, fcl.kind); cs = transition.from; + us = transition.to; } - if (cs.year() > 2037) break; // limit test time (and to 32-bit time_t) + if (us.year() > 2037) break; // limit test time (and to 32-bit time_t) const auto cl_zi = zi.lookup(cs); if (zi.lookup(cl_zi.pre).is_dst == zi.lookup(cl_zi.post).is_dst) { // The "libc" implementation cannot correctly classify transitions @@ -1125,6 +1127,13 @@ TEST(MakeTime, LocalTimeLibC) { EXPECT_EQ(cl_zi.pre, cl_lc.pre); EXPECT_EQ(cl_zi.trans, cl_lc.trans); EXPECT_EQ(cl_zi.post, cl_lc.post); + const auto ucl_zi = zi.lookup(us); + const auto ucl_lc = lc.lookup(us); + SCOPED_TRACE(testing::Message() << "For " << us << " in " << *np); + EXPECT_EQ(ucl_zi.kind, ucl_lc.kind); + EXPECT_EQ(ucl_zi.pre, ucl_lc.pre); + EXPECT_EQ(ucl_zi.trans, ucl_lc.trans); + EXPECT_EQ(ucl_zi.post, ucl_lc.post); } } if (ep == nullptr) { -- cgit v1.2.3