diff options
Diffstat (limited to 'zen')
| -rw-r--r-- | zen/file_path.cpp | 1 | ||||
| -rw-r--r-- | zen/format_unit.cpp | 2 | ||||
| -rw-r--r-- | zen/legacy_compiler.h | 9 | ||||
| -rw-r--r-- | zen/time.h | 99 |
4 files changed, 87 insertions, 24 deletions
diff --git a/zen/file_path.cpp b/zen/file_path.cpp index 68137b90..716dd8de 100644 --- a/zen/file_path.cpp +++ b/zen/file_path.cpp @@ -100,6 +100,7 @@ Zstring zen::appendPath(const Zstring& basePath, const Zstring& relPath) if (relPath.empty()) return basePath; //with or without path separator, e.g. C:\ or C:\folder + //assert(!basePath.empty()); if (basePath.empty()) //basePath might be a relative path, too! return relPath; diff --git a/zen/format_unit.cpp b/zen/format_unit.cpp index 13280b68..2aa6e094 100644 --- a/zen/format_unit.cpp +++ b/zen/format_unit.cpp @@ -170,7 +170,7 @@ std::wstring zen::formatUtcToLocalTime(time_t utcTime) { auto errorMsg = [&] { return _("Error") + L" (time_t: " + numberTo<std::wstring>(utcTime) + L')'; }; - const TimeComp& loc = getLocalTime(utcTime); + const TimeComp& loc = getLocalTime(utcTime); //returns TimeComp() on error std::wstring dateString = utfTo<std::wstring>(formatTime(Zstr("%x %X"), loc)); return !dateString.empty() ? dateString : errorMsg(); diff --git a/zen/legacy_compiler.h b/zen/legacy_compiler.h index 6c9381ee..33394de3 100644 --- a/zen/legacy_compiler.h +++ b/zen/legacy_compiler.h @@ -34,4 +34,13 @@ double fromChars(const char* first, const char* last); const char* toChars(char* first, char* last, double num); } + +#if 0 //neat: supported on MSVC, but not yet on GCC, Clang +auto closure = [](this auto&& self) +{ + self(); //just call ourself until the stack overflows + //e.g. use for: deleteEmptyFolderTask, removeFolderRecursionImpl, scheduleMoreTasks, traverse +}; +#endif + #endif //LEGACY_COMPILER_H_839567308565656789 @@ -26,11 +26,13 @@ struct TimeComp //replaces std::tm and SYSTEMTIME bool operator==(const TimeComp&) const = default; }; -TimeComp getLocalTime(time_t utc = std::time(nullptr)); //convert time_t (UTC) to local time components, returns TimeComp() on error -time_t localToTimeT(const TimeComp& tc); //convert local time components to time_t (UTC), returns -1 on error +TimeComp getUtcTime(time_t utc); //convert time_t (UTC) to UTC time components, returns TimeComp() on error +TimeComp getUtcTime(); //utc = std::time() +std::pair<time_t, bool /*success*/> utcToTimeT(const TimeComp& tc); //convert UTC time components to time_t (UTC) -TimeComp getUtcTime(time_t utc = std::time(nullptr)); //convert time_t (UTC) to UTC time components, returns TimeComp() on error -time_t utcToTimeT(const TimeComp& tc); //convert UTC time components to time_t (UTC), returns -1 on error +TimeComp getLocalTime(time_t utc); //convert time_t (UTC) to local time components, returns TimeComp() on error +TimeComp getLocalTime(); //utc = std::time() +std::pair<time_t, bool /*success*/> localToTimeT(const TimeComp& tc); //convert local time components to time_t (UTC) TimeComp getCompileTime(); //returns TimeComp() on error @@ -134,62 +136,113 @@ bool isValid(const std::tm& t) } +constexpr auto daysPer400Years = 100 * (4 * 365 /*usual days per year*/ + 1 /*including leap day*/) - 3 /*no leap days for centuries, except if divisible by 400 */; +constexpr auto secsPer400Years = 3600LL * 24 * daysPer400Years; + + inline -TimeComp getLocalTime(time_t utc) +TimeComp getUtcTime(time_t utc) { - if (utc == -1) //failure code from std::time(nullptr) - return TimeComp(); + //Windows: gmtime_s() only works for years [1970, 3001] + //=> map into working 400-year range [1970, 2370) + // bonus: avoid asking for bugs for time_t(-1) + const int cycles400 = static_cast<int>(numeric::intDivFloor(utc, secsPer400Years)); + utc -= secsPer400Years * cycles400; std::tm ctc = {}; - if (::localtime_r(&utc, &ctc) == nullptr) + if (::gmtime_r(&utc, &ctc) == nullptr) //Linux, macOS: apparently NO limits (tested years 0 to 10.000!) return TimeComp(); + ctc.tm_year += 400 * cycles400; + return impl::toZenTimeComponents(ctc); } -constexpr auto daysPer400Years = 100 * (4 * 365 /*usual days per year*/ + 1 /*including leap day*/) - 3 /*no leap days for centuries, except if divisible by 400 */; -constexpr auto secsPer400Years = 3600LL * 24 * daysPer400Years; +inline +TimeComp getUtcTime() +{ + const time_t utc = std::time(nullptr); //returns -1 on error + if (utc == -1) + return TimeComp(); + + return getUtcTime(utc); +} inline -TimeComp getUtcTime(time_t utc) +TimeComp getLocalTime(time_t utc) { - if (utc == -1) //failure code from std::time(nullptr) - return TimeComp(); + const int cycles400 = static_cast<int>(numeric::intDivFloor(utc, secsPer400Years)); + utc -= secsPer400Years * cycles400; std::tm ctc = {}; - if (::gmtime_r(&utc, &ctc) == nullptr) //Linux, macOS: apparently NO limits (tested years 0 to 10.000!) + if (::localtime_r(&utc, &ctc) == nullptr) return TimeComp(); + ctc.tm_year += 400 * cycles400; + return impl::toZenTimeComponents(ctc); } inline -time_t localToTimeT(const TimeComp& tc) //returns -1 on error +TimeComp getLocalTime() { - if (tc == TimeComp()) - return -1; + const time_t utc = std::time(nullptr); //returns -1 on error + if (utc == -1) + return TimeComp(); - std::tm ctc = impl::toClibTimeComponents(tc); - return std::mktime(&ctc); + return getLocalTime(utc); } inline -time_t utcToTimeT(const TimeComp& tc) //returns -1 on error +std::pair<time_t, bool /*success*/> utcToTimeT(const TimeComp& tc) { if (tc == TimeComp()) - return -1; + return {}; std::tm ctc = impl::toClibTimeComponents(tc); ctc.tm_isdst = 0; //"Zero (0) to indicate that standard time is in effect" => unused by _mkgmtime, but take no chances + /* Windows: _mkgmtime() only works for years [1970, 3001] + macOS: timegm() requires tm_year >= 1900; apparently no upper limit (tested until year 10.000!) + Linux, 64-bit: apparently NO limits (tested years 0 to 10.000!) + 32-bit: timegm() only works for years [1902, 2038] => sucks to be on 32-bit! :> + + => map into working 400-year range [1970, 2370) + bonus: disambiguate -1 error code from time_t(-1) */ + const int cycles400 = numeric::intDivFloor(ctc.tm_year + 1900 - 1970, 400); + ctc.tm_year -= 400 * cycles400; + + const time_t utc = ::timegm(&ctc); + if (utc == -1) + return {}; + + assert(utc >= 0); + return {utc + secsPer400Years * cycles400, true}; +} + + +inline +std::pair<time_t, bool /*success*/> localToTimeT(const TimeComp& tc) //convert local time components to time_t (UTC) +{ + if (tc == TimeComp()) + return {}; + + std::tm ctc = impl::toClibTimeComponents(tc); - time_t utc = ::timegm(&ctc); + const int cycles400 = numeric::intDivFloor(ctc.tm_year + 1900 - 1971/*[!]*/, 400); //see utcToTimeT() + //1971: ensures resulting time_t >= 0 after time zone, DST adaption, or std::mktime will fail on Windows! + ctc.tm_year -= 400 * cycles400; - return utc; + const time_t locTime = std::mktime(&ctc); + if (locTime == -1) + return {}; + + assert(locTime > 0); + return {locTime + secsPer400Years * cycles400, true}; } |