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-rw-r--r--third_party/abseil_cpp/absl/time/internal/cctz/src/time_zone_format.cc1015
1 files changed, 0 insertions, 1015 deletions
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
deleted file mode 100644
index 2e02233ce1..0000000000
--- a/third_party/abseil_cpp/absl/time/internal/cctz/src/time_zone_format.cc
+++ /dev/null
@@ -1,1015 +0,0 @@
-// 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
-
-// Convert a cctz::weekday to a tm_wday value (0-6, Sunday = 0).
-int ToTmWday(weekday wd) {
-  switch (wd) {
-    case weekday::sunday:
-      return 0;
-    case weekday::monday:
-      return 1;
-    case weekday::tuesday:
-      return 2;
-    case weekday::wednesday:
-      return 3;
-    case weekday::thursday:
-      return 4;
-    case weekday::friday:
-      return 5;
-    case weekday::saturday:
-      return 6;
-  }
-  return 0; /*NOTREACHED*/
-}
-
-// Convert a tm_wday value (0-6, Sunday = 0) to a cctz::weekday.
-weekday FromTmWday(int tm_wday) {
-  switch (tm_wday) {
-    case 0:
-      return weekday::sunday;
-    case 1:
-      return weekday::monday;
-    case 2:
-      return weekday::tuesday;
-    case 3:
-      return weekday::wednesday;
-    case 4:
-      return weekday::thursday;
-    case 5:
-      return weekday::friday;
-    case 6:
-      return weekday::saturday;
-  }
-  return weekday::sunday; /*NOTREACHED*/
-}
-
-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);
-  }
-
-  tm.tm_wday = ToTmWday(get_weekday(al.cs));
-  tm.tm_yday = get_yearday(al.cs) - 1;
-  tm.tm_isdst = al.is_dst ? 1 : 0;
-  return tm;
-}
-
-// Returns the week of the year [0:53] given a civil day and the day on
-// which weeks are defined to start.
-int ToWeek(const civil_day& cd, weekday week_start) {
-  const civil_day d(cd.year() % 400, cd.month(), cd.day());
-  return static_cast<int>((d - prev_weekday(civil_year(d), week_start)) / 7);
-}
-
-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 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)
-//   - %ET  - The RFC3339 "date-time" separator "T"
-//
-// 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("YmdeUuWwHMSzZs%", *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 'U':
-          bp = Format02d(ep, ToWeek(civil_day(al.cs), weekday::sunday));
-          result.append(bp, static_cast<std::size_t>(ep - bp));
-          break;
-        case 'u':
-          bp = Format64(ep, 0, tm.tm_wday ? tm.tm_wday : 7);
-          result.append(bp, static_cast<std::size_t>(ep - bp));
-          break;
-        case 'W':
-          bp = Format02d(ep, ToWeek(civil_day(al.cs), weekday::monday));
-          result.append(bp, static_cast<std::size_t>(ep - bp));
-          break;
-        case 'w':
-          bp = Format64(ep, 0, tm.tm_wday);
-          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 == 'T') {
-      // Formats %ET.
-      if (cur - 2 != pending) {
-        FormatTM(&result, std::string(pending, cur - 2), tm);
-      }
-      result.append("T");
-      pending = ++cur;
-    } else 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' || 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;
-}
-
-// Sets year, tm_mon and tm_mday given the year, week_num, and tm_wday,
-// and the day on which weeks are defined to start.
-void FromWeek(int week_num, weekday week_start, year_t* year, std::tm* tm) {
-  const civil_year y(*year % 400);
-  civil_day cd = prev_weekday(y, week_start);  // week 0
-  cd = next_weekday(cd - 1, FromTmWday(tm->tm_wday)) + (week_num * 7);
-  *year += cd.year() - y.year();
-  tm->tm_mon = cd.month() - 1;
-  tm->tm_mday = cd.day();
-}
-
-}  // 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. %ET accepts either 'T' or 't'.
-//
-// 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;
-  int week_num = -1;
-  weekday week_start = weekday::sunday;
-
-  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;
-        week_num = -1;
-        continue;
-      case 'd':
-      case 'e':
-        data = ParseInt(data, 2, 1, 31, &tm.tm_mday);
-        week_num = -1;
-        continue;
-      case 'U':
-        data = ParseInt(data, 0, 0, 53, &week_num);
-        week_start = weekday::sunday;
-        continue;
-      case 'W':
-        data = ParseInt(data, 0, 0, 53, &week_num);
-        week_start = weekday::monday;
-        continue;
-      case 'u':
-        data = ParseInt(data, 0, 1, 7, &tm.tm_wday);
-        if (data != nullptr) tm.tm_wday %= 7;
-        continue;
-      case 'w':
-        data = ParseInt(data, 0, 0, 6, &tm.tm_wday);
-        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] == 'T') {
-          if (*data == 'T' || *data == 't') {
-            ++data;
-            ++fmt;
-          } else {
-            data = nullptr;
-          }
-          continue;
-        }
-        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 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;
-  }
-
-  // Compute year, tm.tm_mon and tm.tm_mday if we parsed a week number.
-  if (week_num != -1) FromWeek(week_num, week_start, &year, &tm);
-
-  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