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diff --git a/third_party/abseil-cpp/absl/time/internal/cctz/src/time_zone_format.cc b/third_party/abseil-cpp/absl/time/internal/cctz/src/time_zone_format.cc
new file mode 100644
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+++ b/third_party/abseil-cpp/absl/time/internal/cctz/src/time_zone_format.cc
@@ -0,0 +1,922 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#if !defined(HAS_STRPTIME)
+#if !defined(_MSC_VER) && !defined(__MINGW32__)
+#define HAS_STRPTIME 1 // assume everyone has strptime() except windows
+#endif
+#endif
+
+#if defined(HAS_STRPTIME) && HAS_STRPTIME
+#if !defined(_XOPEN_SOURCE)
+#define _XOPEN_SOURCE // Definedness suffices for strptime.
+#endif
+#endif
+
+#include "absl/base/config.h"
+#include "absl/time/internal/cctz/include/cctz/time_zone.h"
+
+// Include time.h directly since, by C++ standards, ctime doesn't have to
+// declare strptime.
+#include <time.h>
+
+#include <cctype>
+#include <chrono>
+#include <cstddef>
+#include <cstdint>
+#include <cstring>
+#include <ctime>
+#include <limits>
+#include <string>
+#include <vector>
+#if !HAS_STRPTIME
+#include <iomanip>
+#include <sstream>
+#endif
+
+#include "absl/time/internal/cctz/include/cctz/civil_time.h"
+#include "time_zone_if.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace time_internal {
+namespace cctz {
+namespace detail {
+
+namespace {
+
+#if !HAS_STRPTIME
+// Build a strptime() using C++11's std::get_time().
+char* strptime(const char* s, const char* fmt, std::tm* tm) {
+ std::istringstream input(s);
+ input >> std::get_time(tm, fmt);
+ if (input.fail()) return nullptr;
+ return const_cast<char*>(s) +
+ (input.eof() ? strlen(s) : static_cast<std::size_t>(input.tellg()));
+}
+#endif
+
+std::tm ToTM(const time_zone::absolute_lookup& al) {
+ std::tm tm{};
+ tm.tm_sec = al.cs.second();
+ tm.tm_min = al.cs.minute();
+ tm.tm_hour = al.cs.hour();
+ tm.tm_mday = al.cs.day();
+ tm.tm_mon = al.cs.month() - 1;
+
+ // Saturate tm.tm_year is cases of over/underflow.
+ if (al.cs.year() < std::numeric_limits<int>::min() + 1900) {
+ tm.tm_year = std::numeric_limits<int>::min();
+ } else if (al.cs.year() - 1900 > std::numeric_limits<int>::max()) {
+ tm.tm_year = std::numeric_limits<int>::max();
+ } else {
+ tm.tm_year = static_cast<int>(al.cs.year() - 1900);
+ }
+
+ switch (get_weekday(al.cs)) {
+ case weekday::sunday:
+ tm.tm_wday = 0;
+ break;
+ case weekday::monday:
+ tm.tm_wday = 1;
+ break;
+ case weekday::tuesday:
+ tm.tm_wday = 2;
+ break;
+ case weekday::wednesday:
+ tm.tm_wday = 3;
+ break;
+ case weekday::thursday:
+ tm.tm_wday = 4;
+ break;
+ case weekday::friday:
+ tm.tm_wday = 5;
+ break;
+ case weekday::saturday:
+ tm.tm_wday = 6;
+ break;
+ }
+ tm.tm_yday = get_yearday(al.cs) - 1;
+ tm.tm_isdst = al.is_dst ? 1 : 0;
+ return tm;
+}
+
+const char kDigits[] = "0123456789";
+
+// Formats a 64-bit integer in the given field width. Note that it is up
+// to the caller of Format64() [and Format02d()/FormatOffset()] to ensure
+// that there is sufficient space before ep to hold the conversion.
+char* Format64(char* ep, int width, std::int_fast64_t v) {
+ bool neg = false;
+ if (v < 0) {
+ --width;
+ neg = true;
+ if (v == std::numeric_limits<std::int_fast64_t>::min()) {
+ // Avoid negating minimum value.
+ std::int_fast64_t last_digit = -(v % 10);
+ v /= 10;
+ if (last_digit < 0) {
+ ++v;
+ last_digit += 10;
+ }
+ --width;
+ *--ep = kDigits[last_digit];
+ }
+ v = -v;
+ }
+ do {
+ --width;
+ *--ep = kDigits[v % 10];
+ } while (v /= 10);
+ while (--width >= 0) *--ep = '0'; // zero pad
+ if (neg) *--ep = '-';
+ return ep;
+}
+
+// Formats [0 .. 99] as %02d.
+char* Format02d(char* ep, int v) {
+ *--ep = kDigits[v % 10];
+ *--ep = kDigits[(v / 10) % 10];
+ return ep;
+}
+
+// Formats a UTC offset, like +00:00.
+char* FormatOffset(char* ep, int offset, const char* mode) {
+ // TODO: Follow the RFC3339 "Unknown Local Offset Convention" and
+ // generate a "negative zero" when we're formatting a zero offset
+ // as the result of a failed load_time_zone().
+ char sign = '+';
+ if (offset < 0) {
+ offset = -offset; // bounded by 24h so no overflow
+ sign = '-';
+ }
+ const int seconds = offset % 60;
+ const int minutes = (offset /= 60) % 60;
+ const int hours = offset /= 60;
+ const char sep = mode[0];
+ const bool ext = (sep != '\0' && mode[1] == '*');
+ const bool ccc = (ext && mode[2] == ':');
+ if (ext && (!ccc || seconds != 0)) {
+ ep = Format02d(ep, seconds);
+ *--ep = sep;
+ } else {
+ // If we're not rendering seconds, sub-minute negative offsets
+ // should get a positive sign (e.g., offset=-10s => "+00:00").
+ if (hours == 0 && minutes == 0) sign = '+';
+ }
+ if (!ccc || minutes != 0 || seconds != 0) {
+ ep = Format02d(ep, minutes);
+ if (sep != '\0') *--ep = sep;
+ }
+ ep = Format02d(ep, hours);
+ *--ep = sign;
+ return ep;
+}
+
+// Formats a std::tm using strftime(3).
+void FormatTM(std::string* out, const std::string& fmt, const std::tm& tm) {
+ // strftime(3) returns the number of characters placed in the output
+ // array (which may be 0 characters). It also returns 0 to indicate
+ // an error, like the array wasn't large enough. To accommodate this,
+ // the following code grows the buffer size from 2x the format std::string
+ // length up to 32x.
+ for (std::size_t i = 2; i != 32; i *= 2) {
+ std::size_t buf_size = fmt.size() * i;
+ std::vector<char> buf(buf_size);
+ if (std::size_t len = strftime(&buf[0], buf_size, fmt.c_str(), &tm)) {
+ out->append(&buf[0], len);
+ return;
+ }
+ }
+}
+
+// Used for %E#S/%E#f specifiers and for data values in parse().
+template <typename T>
+const char* ParseInt(const char* dp, int width, T min, T max, T* vp) {
+ if (dp != nullptr) {
+ const T kmin = std::numeric_limits<T>::min();
+ bool erange = false;
+ bool neg = false;
+ T value = 0;
+ if (*dp == '-') {
+ neg = true;
+ if (width <= 0 || --width != 0) {
+ ++dp;
+ } else {
+ dp = nullptr; // width was 1
+ }
+ }
+ if (const char* const bp = dp) {
+ while (const char* cp = strchr(kDigits, *dp)) {
+ int d = static_cast<int>(cp - kDigits);
+ if (d >= 10) break;
+ if (value < kmin / 10) {
+ erange = true;
+ break;
+ }
+ value *= 10;
+ if (value < kmin + d) {
+ erange = true;
+ break;
+ }
+ value -= d;
+ dp += 1;
+ if (width > 0 && --width == 0) break;
+ }
+ if (dp != bp && !erange && (neg || value != kmin)) {
+ if (!neg || value != 0) {
+ if (!neg) value = -value; // make positive
+ if (min <= value && value <= max) {
+ *vp = value;
+ } else {
+ dp = nullptr;
+ }
+ } else {
+ dp = nullptr;
+ }
+ } else {
+ dp = nullptr;
+ }
+ }
+ }
+ return dp;
+}
+
+// The number of base-10 digits that can be represented by a signed 64-bit
+// integer. That is, 10^kDigits10_64 <= 2^63 - 1 < 10^(kDigits10_64 + 1).
+const int kDigits10_64 = 18;
+
+// 10^n for everything that can be represented by a signed 64-bit integer.
+const std::int_fast64_t kExp10[kDigits10_64 + 1] = {
+ 1,
+ 10,
+ 100,
+ 1000,
+ 10000,
+ 100000,
+ 1000000,
+ 10000000,
+ 100000000,
+ 1000000000,
+ 10000000000,
+ 100000000000,
+ 1000000000000,
+ 10000000000000,
+ 100000000000000,
+ 1000000000000000,
+ 10000000000000000,
+ 100000000000000000,
+ 1000000000000000000,
+};
+
+} // namespace
+
+// Uses strftime(3) to format the given Time. The following extended format
+// specifiers are also supported:
+//
+// - %Ez - RFC3339-compatible numeric UTC offset (+hh:mm or -hh:mm)
+// - %E*z - Full-resolution numeric UTC offset (+hh:mm:ss or -hh:mm:ss)
+// - %E#S - Seconds with # digits of fractional precision
+// - %E*S - Seconds with full fractional precision (a literal '*')
+// - %E4Y - Four-character years (-999 ... -001, 0000, 0001 ... 9999)
+//
+// The standard specifiers from RFC3339_* (%Y, %m, %d, %H, %M, and %S) are
+// handled internally for performance reasons. strftime(3) is slow due to
+// a POSIX requirement to respect changes to ${TZ}.
+//
+// The TZ/GNU %s extension is handled internally because strftime() has
+// to use mktime() to generate it, and that assumes the local time zone.
+//
+// We also handle the %z and %Z specifiers to accommodate platforms that do
+// not support the tm_gmtoff and tm_zone extensions to std::tm.
+//
+// Requires that zero() <= fs < seconds(1).
+std::string format(const std::string& format, const time_point<seconds>& tp,
+ const detail::femtoseconds& fs, const time_zone& tz) {
+ std::string result;
+ result.reserve(format.size()); // A reasonable guess for the result size.
+ const time_zone::absolute_lookup al = tz.lookup(tp);
+ const std::tm tm = ToTM(al);
+
+ // Scratch buffer for internal conversions.
+ char buf[3 + kDigits10_64]; // enough for longest conversion
+ char* const ep = buf + sizeof(buf);
+ char* bp; // works back from ep
+
+ // Maintain three, disjoint subsequences that span format.
+ // [format.begin() ... pending) : already formatted into result
+ // [pending ... cur) : formatting pending, but no special cases
+ // [cur ... format.end()) : unexamined
+ // Initially, everything is in the unexamined part.
+ const char* pending = format.c_str(); // NUL terminated
+ const char* cur = pending;
+ const char* end = pending + format.length();
+
+ while (cur != end) { // while something is unexamined
+ // Moves cur to the next percent sign.
+ const char* start = cur;
+ while (cur != end && *cur != '%') ++cur;
+
+ // If the new pending text is all ordinary, copy it out.
+ if (cur != start && pending == start) {
+ result.append(pending, static_cast<std::size_t>(cur - pending));
+ pending = start = cur;
+ }
+
+ // Span the sequential percent signs.
+ const char* percent = cur;
+ while (cur != end && *cur == '%') ++cur;
+
+ // If the new pending text is all percents, copy out one
+ // percent for every matched pair, then skip those pairs.
+ if (cur != start && pending == start) {
+ std::size_t escaped = static_cast<std::size_t>(cur - pending) / 2;
+ result.append(pending, escaped);
+ pending += escaped * 2;
+ // Also copy out a single trailing percent.
+ if (pending != cur && cur == end) {
+ result.push_back(*pending++);
+ }
+ }
+
+ // Loop unless we have an unescaped percent.
+ if (cur == end || (cur - percent) % 2 == 0) continue;
+
+ // Simple specifiers that we handle ourselves.
+ if (strchr("YmdeHMSzZs%", *cur)) {
+ if (cur - 1 != pending) {
+ FormatTM(&result, std::string(pending, cur - 1), tm);
+ }
+ switch (*cur) {
+ case 'Y':
+ // This avoids the tm.tm_year overflow problem for %Y, however
+ // tm.tm_year will still be used by other specifiers like %D.
+ bp = Format64(ep, 0, al.cs.year());
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ break;
+ case 'm':
+ bp = Format02d(ep, al.cs.month());
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ break;
+ case 'd':
+ case 'e':
+ bp = Format02d(ep, al.cs.day());
+ if (*cur == 'e' && *bp == '0') *bp = ' '; // for Windows
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ break;
+ case 'H':
+ bp = Format02d(ep, al.cs.hour());
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ break;
+ case 'M':
+ bp = Format02d(ep, al.cs.minute());
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ break;
+ case 'S':
+ bp = Format02d(ep, al.cs.second());
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ break;
+ case 'z':
+ bp = FormatOffset(ep, al.offset, "");
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ break;
+ case 'Z':
+ result.append(al.abbr);
+ break;
+ case 's':
+ bp = Format64(ep, 0, ToUnixSeconds(tp));
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ break;
+ case '%':
+ result.push_back('%');
+ break;
+ }
+ pending = ++cur;
+ continue;
+ }
+
+ // More complex specifiers that we handle ourselves.
+ if (*cur == ':' && cur + 1 != end) {
+ if (*(cur + 1) == 'z') {
+ // Formats %:z.
+ if (cur - 1 != pending) {
+ FormatTM(&result, std::string(pending, cur - 1), tm);
+ }
+ bp = FormatOffset(ep, al.offset, ":");
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ pending = cur += 2;
+ continue;
+ }
+ if (*(cur + 1) == ':' && cur + 2 != end) {
+ if (*(cur + 2) == 'z') {
+ // Formats %::z.
+ if (cur - 1 != pending) {
+ FormatTM(&result, std::string(pending, cur - 1), tm);
+ }
+ bp = FormatOffset(ep, al.offset, ":*");
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ pending = cur += 3;
+ continue;
+ }
+ if (*(cur + 2) == ':' && cur + 3 != end) {
+ if (*(cur + 3) == 'z') {
+ // Formats %:::z.
+ if (cur - 1 != pending) {
+ FormatTM(&result, std::string(pending, cur - 1), tm);
+ }
+ bp = FormatOffset(ep, al.offset, ":*:");
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ pending = cur += 4;
+ continue;
+ }
+ }
+ }
+ }
+
+ // Loop if there is no E modifier.
+ if (*cur != 'E' || ++cur == end) continue;
+
+ // Format our extensions.
+ if (*cur == 'z') {
+ // Formats %Ez.
+ if (cur - 2 != pending) {
+ FormatTM(&result, std::string(pending, cur - 2), tm);
+ }
+ bp = FormatOffset(ep, al.offset, ":");
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ pending = ++cur;
+ } else if (*cur == '*' && cur + 1 != end && *(cur + 1) == 'z') {
+ // Formats %E*z.
+ if (cur - 2 != pending) {
+ FormatTM(&result, std::string(pending, cur - 2), tm);
+ }
+ bp = FormatOffset(ep, al.offset, ":*");
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ pending = cur += 2;
+ } else if (*cur == '*' && cur + 1 != end &&
+ (*(cur + 1) == 'S' || *(cur + 1) == 'f')) {
+ // Formats %E*S or %E*F.
+ if (cur - 2 != pending) {
+ FormatTM(&result, std::string(pending, cur - 2), tm);
+ }
+ char* cp = ep;
+ bp = Format64(cp, 15, fs.count());
+ while (cp != bp && cp[-1] == '0') --cp;
+ switch (*(cur + 1)) {
+ case 'S':
+ if (cp != bp) *--bp = '.';
+ bp = Format02d(bp, al.cs.second());
+ break;
+ case 'f':
+ if (cp == bp) *--bp = '0';
+ break;
+ }
+ result.append(bp, static_cast<std::size_t>(cp - bp));
+ pending = cur += 2;
+ } else if (*cur == '4' && cur + 1 != end && *(cur + 1) == 'Y') {
+ // Formats %E4Y.
+ if (cur - 2 != pending) {
+ FormatTM(&result, std::string(pending, cur - 2), tm);
+ }
+ bp = Format64(ep, 4, al.cs.year());
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ pending = cur += 2;
+ } else if (std::isdigit(*cur)) {
+ // Possibly found %E#S or %E#f.
+ int n = 0;
+ if (const char* np = ParseInt(cur, 0, 0, 1024, &n)) {
+ if (*np == 'S' || *np == 'f') {
+ // Formats %E#S or %E#f.
+ if (cur - 2 != pending) {
+ FormatTM(&result, std::string(pending, cur - 2), tm);
+ }
+ bp = ep;
+ if (n > 0) {
+ if (n > kDigits10_64) n = kDigits10_64;
+ bp = Format64(bp, n,
+ (n > 15) ? fs.count() * kExp10[n - 15]
+ : fs.count() / kExp10[15 - n]);
+ if (*np == 'S') *--bp = '.';
+ }
+ if (*np == 'S') bp = Format02d(bp, al.cs.second());
+ result.append(bp, static_cast<std::size_t>(ep - bp));
+ pending = cur = ++np;
+ }
+ }
+ }
+ }
+
+ // Formats any remaining data.
+ if (end != pending) {
+ FormatTM(&result, std::string(pending, end), tm);
+ }
+
+ return result;
+}
+
+namespace {
+
+const char* ParseOffset(const char* dp, const char* mode, int* offset) {
+ if (dp != nullptr) {
+ const char first = *dp++;
+ if (first == '+' || first == '-') {
+ char sep = mode[0];
+ int hours = 0;
+ int minutes = 0;
+ int seconds = 0;
+ const char* ap = ParseInt(dp, 2, 0, 23, &hours);
+ if (ap != nullptr && ap - dp == 2) {
+ dp = ap;
+ if (sep != '\0' && *ap == sep) ++ap;
+ const char* bp = ParseInt(ap, 2, 0, 59, &minutes);
+ if (bp != nullptr && bp - ap == 2) {
+ dp = bp;
+ if (sep != '\0' && *bp == sep) ++bp;
+ const char* cp = ParseInt(bp, 2, 0, 59, &seconds);
+ if (cp != nullptr && cp - bp == 2) dp = cp;
+ }
+ *offset = ((hours * 60 + minutes) * 60) + seconds;
+ if (first == '-') *offset = -*offset;
+ } else {
+ dp = nullptr;
+ }
+ } else if (first == 'Z') { // Zulu
+ *offset = 0;
+ } else {
+ dp = nullptr;
+ }
+ }
+ return dp;
+}
+
+const char* ParseZone(const char* dp, std::string* zone) {
+ zone->clear();
+ if (dp != nullptr) {
+ while (*dp != '\0' && !std::isspace(*dp)) zone->push_back(*dp++);
+ if (zone->empty()) dp = nullptr;
+ }
+ return dp;
+}
+
+const char* ParseSubSeconds(const char* dp, detail::femtoseconds* subseconds) {
+ if (dp != nullptr) {
+ std::int_fast64_t v = 0;
+ std::int_fast64_t exp = 0;
+ const char* const bp = dp;
+ while (const char* cp = strchr(kDigits, *dp)) {
+ int d = static_cast<int>(cp - kDigits);
+ if (d >= 10) break;
+ if (exp < 15) {
+ exp += 1;
+ v *= 10;
+ v += d;
+ }
+ ++dp;
+ }
+ if (dp != bp) {
+ v *= kExp10[15 - exp];
+ *subseconds = detail::femtoseconds(v);
+ } else {
+ dp = nullptr;
+ }
+ }
+ return dp;
+}
+
+// Parses a string into a std::tm using strptime(3).
+const char* ParseTM(const char* dp, const char* fmt, std::tm* tm) {
+ if (dp != nullptr) {
+ dp = strptime(dp, fmt, tm);
+ }
+ return dp;
+}
+
+} // namespace
+
+// Uses strptime(3) to parse the given input. Supports the same extended
+// format specifiers as format(), although %E#S and %E*S are treated
+// identically (and similarly for %E#f and %E*f). %Ez and %E*z also accept
+// the same inputs.
+//
+// The standard specifiers from RFC3339_* (%Y, %m, %d, %H, %M, and %S) are
+// handled internally so that we can normally avoid strptime() altogether
+// (which is particularly helpful when the native implementation is broken).
+//
+// The TZ/GNU %s extension is handled internally because strptime() has to
+// use localtime_r() to generate it, and that assumes the local time zone.
+//
+// We also handle the %z specifier to accommodate platforms that do not
+// support the tm_gmtoff extension to std::tm. %Z is parsed but ignored.
+bool parse(const std::string& format, const std::string& input,
+ const time_zone& tz, time_point<seconds>* sec,
+ detail::femtoseconds* fs, std::string* err) {
+ // The unparsed input.
+ const char* data = input.c_str(); // NUL terminated
+
+ // Skips leading whitespace.
+ while (std::isspace(*data)) ++data;
+
+ const year_t kyearmax = std::numeric_limits<year_t>::max();
+ const year_t kyearmin = std::numeric_limits<year_t>::min();
+
+ // Sets default values for unspecified fields.
+ bool saw_year = false;
+ year_t year = 1970;
+ std::tm tm{};
+ tm.tm_year = 1970 - 1900;
+ tm.tm_mon = 1 - 1; // Jan
+ tm.tm_mday = 1;
+ tm.tm_hour = 0;
+ tm.tm_min = 0;
+ tm.tm_sec = 0;
+ tm.tm_wday = 4; // Thu
+ tm.tm_yday = 0;
+ tm.tm_isdst = 0;
+ auto subseconds = detail::femtoseconds::zero();
+ bool saw_offset = false;
+ int offset = 0; // No offset from passed tz.
+ std::string zone = "UTC";
+
+ const char* fmt = format.c_str(); // NUL terminated
+ bool twelve_hour = false;
+ bool afternoon = false;
+
+ bool saw_percent_s = false;
+ std::int_fast64_t percent_s = 0;
+
+ // Steps through format, one specifier at a time.
+ while (data != nullptr && *fmt != '\0') {
+ if (std::isspace(*fmt)) {
+ while (std::isspace(*data)) ++data;
+ while (std::isspace(*++fmt)) continue;
+ continue;
+ }
+
+ if (*fmt != '%') {
+ if (*data == *fmt) {
+ ++data;
+ ++fmt;
+ } else {
+ data = nullptr;
+ }
+ continue;
+ }
+
+ const char* percent = fmt;
+ if (*++fmt == '\0') {
+ data = nullptr;
+ continue;
+ }
+ switch (*fmt++) {
+ case 'Y':
+ // Symmetrically with FormatTime(), directly handing %Y avoids the
+ // tm.tm_year overflow problem. However, tm.tm_year will still be
+ // used by other specifiers like %D.
+ data = ParseInt(data, 0, kyearmin, kyearmax, &year);
+ if (data != nullptr) saw_year = true;
+ continue;
+ case 'm':
+ data = ParseInt(data, 2, 1, 12, &tm.tm_mon);
+ if (data != nullptr) tm.tm_mon -= 1;
+ continue;
+ case 'd':
+ case 'e':
+ data = ParseInt(data, 2, 1, 31, &tm.tm_mday);
+ continue;
+ case 'H':
+ data = ParseInt(data, 2, 0, 23, &tm.tm_hour);
+ twelve_hour = false;
+ continue;
+ case 'M':
+ data = ParseInt(data, 2, 0, 59, &tm.tm_min);
+ continue;
+ case 'S':
+ data = ParseInt(data, 2, 0, 60, &tm.tm_sec);
+ continue;
+ case 'I':
+ case 'l':
+ case 'r': // probably uses %I
+ twelve_hour = true;
+ break;
+ case 'R': // uses %H
+ case 'T': // uses %H
+ case 'c': // probably uses %H
+ case 'X': // probably uses %H
+ twelve_hour = false;
+ break;
+ case 'z':
+ data = ParseOffset(data, "", &offset);
+ if (data != nullptr) saw_offset = true;
+ continue;
+ case 'Z': // ignored; zone abbreviations are ambiguous
+ data = ParseZone(data, &zone);
+ continue;
+ case 's':
+ data =
+ ParseInt(data, 0, std::numeric_limits<std::int_fast64_t>::min(),
+ std::numeric_limits<std::int_fast64_t>::max(), &percent_s);
+ if (data != nullptr) saw_percent_s = true;
+ continue;
+ case ':':
+ if (fmt[0] == 'z' ||
+ (fmt[0] == ':' &&
+ (fmt[1] == 'z' || (fmt[1] == ':' && fmt[2] == 'z')))) {
+ data = ParseOffset(data, ":", &offset);
+ if (data != nullptr) saw_offset = true;
+ fmt += (fmt[0] == 'z') ? 1 : (fmt[1] == 'z') ? 2 : 3;
+ continue;
+ }
+ break;
+ case '%':
+ data = (*data == '%' ? data + 1 : nullptr);
+ continue;
+ case 'E':
+ if (fmt[0] == 'z' || (fmt[0] == '*' && fmt[1] == 'z')) {
+ data = ParseOffset(data, ":", &offset);
+ if (data != nullptr) saw_offset = true;
+ fmt += (fmt[0] == 'z') ? 1 : 2;
+ continue;
+ }
+ if (fmt[0] == '*' && fmt[1] == 'S') {
+ data = ParseInt(data, 2, 0, 60, &tm.tm_sec);
+ if (data != nullptr && *data == '.') {
+ data = ParseSubSeconds(data + 1, &subseconds);
+ }
+ fmt += 2;
+ continue;
+ }
+ if (fmt[0] == '*' && fmt[1] == 'f') {
+ if (data != nullptr && std::isdigit(*data)) {
+ data = ParseSubSeconds(data, &subseconds);
+ }
+ fmt += 2;
+ continue;
+ }
+ if (fmt[0] == '4' && fmt[1] == 'Y') {
+ const char* bp = data;
+ data = ParseInt(data, 4, year_t{-999}, year_t{9999}, &year);
+ if (data != nullptr) {
+ if (data - bp == 4) {
+ saw_year = true;
+ } else {
+ data = nullptr; // stopped too soon
+ }
+ }
+ fmt += 2;
+ continue;
+ }
+ if (std::isdigit(*fmt)) {
+ int n = 0; // value ignored
+ if (const char* np = ParseInt(fmt, 0, 0, 1024, &n)) {
+ if (*np == 'S') {
+ data = ParseInt(data, 2, 0, 60, &tm.tm_sec);
+ if (data != nullptr && *data == '.') {
+ data = ParseSubSeconds(data + 1, &subseconds);
+ }
+ fmt = ++np;
+ continue;
+ }
+ if (*np == 'f') {
+ if (data != nullptr && std::isdigit(*data)) {
+ data = ParseSubSeconds(data, &subseconds);
+ }
+ fmt = ++np;
+ continue;
+ }
+ }
+ }
+ if (*fmt == 'c') twelve_hour = false; // probably uses %H
+ if (*fmt == 'X') twelve_hour = false; // probably uses %H
+ if (*fmt != '\0') ++fmt;
+ break;
+ case 'O':
+ if (*fmt == 'H') twelve_hour = false;
+ if (*fmt == 'I') twelve_hour = true;
+ if (*fmt != '\0') ++fmt;
+ break;
+ }
+
+ // Parses the current specifier.
+ const char* orig_data = data;
+ std::string spec(percent, static_cast<std::size_t>(fmt - percent));
+ data = ParseTM(data, spec.c_str(), &tm);
+
+ // If we successfully parsed %p we need to remember whether the result
+ // was AM or PM so that we can adjust tm_hour before time_zone::lookup().
+ // So reparse the input with a known AM hour, and check if it is shifted
+ // to a PM hour.
+ if (spec == "%p" && data != nullptr) {
+ std::string test_input = "1";
+ test_input.append(orig_data, static_cast<std::size_t>(data - orig_data));
+ const char* test_data = test_input.c_str();
+ std::tm tmp{};
+ ParseTM(test_data, "%I%p", &tmp);
+ afternoon = (tmp.tm_hour == 13);
+ }
+ }
+
+ // Adjust a 12-hour tm_hour value if it should be in the afternoon.
+ if (twelve_hour && afternoon && tm.tm_hour < 12) {
+ tm.tm_hour += 12;
+ }
+
+ if (data == nullptr) {
+ if (err != nullptr) *err = "Failed to parse input";
+ return false;
+ }
+
+ // Skip any remaining whitespace.
+ while (std::isspace(*data)) ++data;
+
+ // parse() must consume the entire input std::string.
+ if (*data != '\0') {
+ if (err != nullptr) *err = "Illegal trailing data in input string";
+ return false;
+ }
+
+ // If we saw %s then we ignore anything else and return that time.
+ if (saw_percent_s) {
+ *sec = FromUnixSeconds(percent_s);
+ *fs = detail::femtoseconds::zero();
+ return true;
+ }
+
+ // If we saw %z, %Ez, or %E*z then we want to interpret the parsed fields
+ // in UTC and then shift by that offset. Otherwise we want to interpret
+ // the fields directly in the passed time_zone.
+ time_zone ptz = saw_offset ? utc_time_zone() : tz;
+
+ // Allows a leap second of 60 to normalize forward to the following ":00".
+ if (tm.tm_sec == 60) {
+ tm.tm_sec -= 1;
+ offset -= 1;
+ subseconds = detail::femtoseconds::zero();
+ }
+
+ if (!saw_year) {
+ year = year_t{tm.tm_year};
+ if (year > kyearmax - 1900) {
+ // Platform-dependent, maybe unreachable.
+ if (err != nullptr) *err = "Out-of-range year";
+ return false;
+ }
+ year += 1900;
+ }
+
+ const int month = tm.tm_mon + 1;
+ civil_second cs(year, month, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec);
+
+ // parse() should not allow normalization. Due to the restricted field
+ // ranges above (see ParseInt()), the only possibility is for days to roll
+ // into months. That is, parsing "Sep 31" should not produce "Oct 1".
+ if (cs.month() != month || cs.day() != tm.tm_mday) {
+ if (err != nullptr) *err = "Out-of-range field";
+ return false;
+ }
+
+ // Accounts for the offset adjustment before converting to absolute time.
+ if ((offset < 0 && cs > civil_second::max() + offset) ||
+ (offset > 0 && cs < civil_second::min() + offset)) {
+ if (err != nullptr) *err = "Out-of-range field";
+ return false;
+ }
+ cs -= offset;
+
+ const auto tp = ptz.lookup(cs).pre;
+ // Checks for overflow/underflow and returns an error as necessary.
+ if (tp == time_point<seconds>::max()) {
+ const auto al = ptz.lookup(time_point<seconds>::max());
+ if (cs > al.cs) {
+ if (err != nullptr) *err = "Out-of-range field";
+ return false;
+ }
+ }
+ if (tp == time_point<seconds>::min()) {
+ const auto al = ptz.lookup(time_point<seconds>::min());
+ if (cs < al.cs) {
+ if (err != nullptr) *err = "Out-of-range field";
+ return false;
+ }
+ }
+
+ *sec = tp;
+ *fs = subseconds;
+ return true;
+}
+
+} // namespace detail
+} // namespace cctz
+} // namespace time_internal
+ABSL_NAMESPACE_END
+} // namespace absl
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-24 06:04:33 +0000