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author | Feng Xiao <xfxyjwf@gmail.com> | 2015-06-15 18:21:48 -0700 |
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committer | Feng Xiao <xfxyjwf@gmail.com> | 2015-06-15 18:24:01 -0700 |
commit | e96ff30120a3834f7d1e31e43e591bf7cfbd731f (patch) | |
tree | 7e4c317912ac3809fbff11bb692084debd4a27eb /src/google/protobuf/stubs/time.cc | |
parent | 4cbb612299eaf8259db25f5dcda46022fbd1db54 (diff) | |
download | protobuf-e96ff30120a3834f7d1e31e43e591bf7cfbd731f.tar.gz protobuf-e96ff30120a3834f7d1e31e43e591bf7cfbd731f.tar.bz2 protobuf-e96ff30120a3834f7d1e31e43e591bf7cfbd731f.zip |
Down-integrate from internal code base.
[ci skip]
Change-Id: I9391c09640e0b0b2b21c45a97a1fc91814d95c5d
Diffstat (limited to 'src/google/protobuf/stubs/time.cc')
-rw-r--r-- | src/google/protobuf/stubs/time.cc | 364 |
1 files changed, 364 insertions, 0 deletions
diff --git a/src/google/protobuf/stubs/time.cc b/src/google/protobuf/stubs/time.cc new file mode 100644 index 00000000..73b99af6 --- /dev/null +++ b/src/google/protobuf/stubs/time.cc @@ -0,0 +1,364 @@ +#include <google/protobuf/stubs/time.h> + +#include <google/protobuf/stubs/stringprintf.h> +#include <google/protobuf/stubs/strutil.h> + +namespace google { +namespace protobuf { +namespace internal { + +namespace { +static const int64 kSecondsPerMinute = 60; +static const int64 kSecondsPerHour = 3600; +static const int64 kSecondsPerDay = kSecondsPerHour * 24; +static const int64 kSecondsPer400Years = + kSecondsPerDay * (400 * 365 + 400 / 4 - 3); +// Seconds from 0001-01-01T00:00:00 to 1970-01-01T:00:00:00 +static const int64 kSecondsFromEraToEpoch = 62135596800LL; +// The range of timestamp values we support. +static const int64 kMinTime = -62135596800LL; // 0001-01-01T00:00:00 +static const int64 kMaxTime = 253402300799LL; // 9999-12-31T23:59:59 + +static const int kNanosPerSecond = 1000000000; +static const int kNanosPerMillisecond = 1000000; +static const int kNanosPerMicrosecond = 1000; + +// Count the seconds from the given year (start at Jan 1, 00:00) to 100 years +// after. +int64 SecondsPer100Years(int year) { + if (year % 400 == 0 || year % 400 > 300) { + return kSecondsPerDay * (100 * 365 + 100 / 4); + } else { + return kSecondsPerDay * (100 * 365 + 100 / 4 - 1); + } +} + +// Count the seconds from the given year (start at Jan 1, 00:00) to 4 years +// after. +int64 SecondsPer4Years(int year) { + if ((year % 100 == 0 || year % 100 > 96) && + !(year % 400 == 0 || year % 400 > 396)) { + // No leap years. + return kSecondsPerDay * (4 * 365); + } else { + // One leap years. + return kSecondsPerDay * (4 * 365 + 1); + } +} + +bool IsLeapYear(int year) { + return year % 400 == 0 || (year % 4 == 0 && year % 100 != 0); +} + +int64 SecondsPerYear(int year) { + return kSecondsPerDay * (IsLeapYear(year) ? 366 : 365); +} + +static const int kDaysInMonth[13] = { + 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 +}; + +int64 SecondsPerMonth(int month, bool leap) { + if (month == 2 && leap) { + return kSecondsPerDay * (kDaysInMonth[month] + 1); + } + return kSecondsPerDay * kDaysInMonth[month]; +} + +static const int kDaysSinceJan[13] = { + 0, 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, +}; + +bool ValidateDateTime(const DateTime& time) { + if (time.year < 1 || time.year > 9999 || + time.month < 1 || time.month > 12 || + time.day < 1 || time.day > 31 || + time.hour < 0 || time.hour > 23 || + time.minute < 0 || time.minute > 59 || + time.second < 0 || time.second > 59) { + return false; + } + if (time.month == 2 && IsLeapYear(time.year)) { + return time.month <= kDaysInMonth[time.month] + 1; + } else { + return time.month <= kDaysInMonth[time.month]; + } +} + +// Count the number of seconds elapsed from 0001-01-01T00:00:00 to the given +// time. +int64 SecondsSinceCommonEra(const DateTime& time) { + int64 result = 0; + // Years should be between 1 and 9999. + assert(time.year >= 1 && time.year <= 9999); + int year = 1; + if ((time.year - year) >= 400) { + int count_400years = (time.year - year) / 400; + result += kSecondsPer400Years * count_400years; + year += count_400years * 400; + } + while ((time.year - year) >= 100) { + result += SecondsPer100Years(year); + year += 100; + } + while ((time.year - year) >= 4) { + result += SecondsPer4Years(year); + year += 4; + } + while (time.year > year) { + result += SecondsPerYear(year); + ++year; + } + // Months should be between 1 and 12. + assert(time.month >= 1 && time.month <= 12); + int month = time.month; + result += kSecondsPerDay * kDaysSinceJan[month]; + if (month > 2 && IsLeapYear(year)) { + result += kSecondsPerDay; + } + assert(time.day >= 1 && + time.day <= (month == 2 && IsLeapYear(year) + ? kDaysInMonth[month] + 1 + : kDaysInMonth[month])); + result += kSecondsPerDay * (time.day - 1); + result += kSecondsPerHour * time.hour + + kSecondsPerMinute * time.minute + + time.second; + return result; +} + +// Format nanoseconds with either 3, 6, or 9 digits depending on the required +// precision to represent the exact value. +string FormatNanos(int32 nanos) { + if (nanos % kNanosPerMillisecond == 0) { + return StringPrintf("%03d", nanos / kNanosPerMillisecond); + } else if (nanos % kNanosPerMicrosecond == 0) { + return StringPrintf("%06d", nanos / kNanosPerMicrosecond); + } else { + return StringPrintf("%09d", nanos); + } +} + +// Parses an integer from a null-terminated char sequence. The method +// consumes at most "width" chars. Returns a pointer after the consumed +// integer, or NULL if the data does not start with an integer or the +// integer value does not fall in the range of [min_value, max_value]. +const char* ParseInt(const char* data, int width, int min_value, + int max_value, int* result) { + if (!ascii_isdigit(*data)) { + return NULL; + } + int value = 0; + for (int i = 0; i < width; ++i, ++data) { + if (ascii_isdigit(*data)) { + value = value * 10 + (*data - '0'); + } else { + break; + } + } + if (value >= min_value && value <= max_value) { + *result = value; + return data; + } else { + return NULL; + } +} + +// Consumes the fractional parts of a second into nanos. For example, +// "010" will be parsed to 10000000 nanos. +const char* ParseNanos(const char* data, int32* nanos) { + if (!ascii_isdigit(*data)) { + return NULL; + } + int value = 0; + int len = 0; + // Consume as many digits as there are but only take the first 9 into + // account. + while (ascii_isdigit(*data)) { + if (len < 9) { + value = value * 10 + *data - '0'; + } + ++len; + ++data; + } + while (len < 9) { + value = value * 10; + ++len; + } + *nanos = value; + return data; +} + +const char* ParseTimezoneOffset(const char* data, int64* offset) { + // Accept format "HH:MM". E.g., "08:00" + int hour; + if ((data = ParseInt(data, 2, 0, 23, &hour)) == NULL) { + return NULL; + } + if (*data++ != ':') { + return NULL; + } + int minute; + if ((data = ParseInt(data, 2, 0, 59, &minute)) == NULL) { + return NULL; + } + *offset = (hour * 60 + minute) * 60; + return data; +} +} // namespace + +bool SecondsToDateTime(int64 seconds, DateTime* time) { + if (seconds < kMinTime || seconds > kMaxTime) { + return false; + } + // It's easier to calcuate the DateTime starting from 0001-01-01T00:00:00 + seconds = seconds + kSecondsFromEraToEpoch; + int year = 1; + if (seconds >= kSecondsPer400Years) { + int count_400years = seconds / kSecondsPer400Years; + year += 400 * count_400years; + seconds %= kSecondsPer400Years; + } + while (seconds >= SecondsPer100Years(year)) { + seconds -= SecondsPer100Years(year); + year += 100; + } + while (seconds >= SecondsPer4Years(year)) { + seconds -= SecondsPer4Years(year); + year += 4; + } + while (seconds >= SecondsPerYear(year)) { + seconds -= SecondsPerYear(year); + year += 1; + } + bool leap = IsLeapYear(year); + int month = 1; + while (seconds >= SecondsPerMonth(month, leap)) { + seconds -= SecondsPerMonth(month, leap); + ++month; + } + int day = 1 + seconds / kSecondsPerDay; + seconds %= kSecondsPerDay; + int hour = seconds / kSecondsPerHour; + seconds %= kSecondsPerHour; + int minute = seconds / kSecondsPerMinute; + seconds %= kSecondsPerMinute; + time->year = year; + time->month = month; + time->day = day; + time->hour = hour; + time->minute = minute; + time->second = static_cast<int>(seconds); + return true; +} + +bool DateTimeToSeconds(const DateTime& time, int64* seconds) { + if (!ValidateDateTime(time)) { + return false; + } + *seconds = SecondsSinceCommonEra(time) - kSecondsFromEraToEpoch; + return true; +} + +void GetCurrentTime(int64* seconds, int32* nanos) { + // TODO(xiaofeng): Improve the accuracy of this implementation (or just + // remove this method from protobuf). + *seconds = time(NULL); + *nanos = 0; +} + +string FormatTime(int64 seconds, int32 nanos) { + DateTime time; + if (nanos < 0 || nanos > 999999999 || !SecondsToDateTime(seconds, &time)) { + return "InvalidTime"; + } + string result = StringPrintf("%04d-%02d-%02dT%02d:%02d:%02d", + time.year, time.month, time.day, + time.hour, time.minute, time.second); + if (nanos != 0) { + result += "." + FormatNanos(nanos); + } + return result + "Z"; +} + +bool ParseTime(const string& value, int64* seconds, int32* nanos) { + DateTime time; + const char* data = value.c_str(); + // We only accept: + // Z-normalized: 2015-05-20T13:29:35.120Z + // With UTC offset: 2015-05-20T13:29:35.120-08:00 + + // Parse year + if ((data = ParseInt(data, 4, 1, 9999, &time.year)) == NULL) { + return false; + } + // Expect '-' + if (*data++ != '-') return false; + // Parse month + if ((data = ParseInt(data, 2, 1, 12, &time.month)) == NULL) { + return false; + } + // Expect '-' + if (*data++ != '-') return false; + // Parse day + if ((data = ParseInt(data, 2, 1, 31, &time.day)) == NULL) { + return false; + } + // Expect 'T' + if (*data++ != 'T') return false; + // Parse hour + if ((data = ParseInt(data, 2, 0, 23, &time.hour)) == NULL) { + return false; + } + // Expect ':' + if (*data++ != ':') return false; + // Parse minute + if ((data = ParseInt(data, 2, 0, 59, &time.minute)) == NULL) { + return false; + } + // Expect ':' + if (*data++ != ':') return false; + // Parse second + if ((data = ParseInt(data, 2, 0, 59, &time.second)) == NULL) { + return false; + } + if (!DateTimeToSeconds(time, seconds)) { + return false; + } + // Parse nanoseconds. + if (*data == '.') { + ++data; + // Parse nanoseconds. + if ((data = ParseNanos(data, nanos)) == NULL) { + return false; + } + } else { + *nanos = 0; + } + // Parse UTC offsets. + if (*data == 'Z') { + ++data; + } else if (*data == '+') { + ++data; + int64 offset; + if ((data = ParseTimezoneOffset(data, &offset)) == NULL) { + return false; + } + *seconds -= offset; + } else if (*data == '-') { + ++data; + int64 offset; + if ((data = ParseTimezoneOffset(data, &offset)) == NULL) { + return false; + } + *seconds += offset; + } else { + return false; + } + // Done with parsing. + return *data == 0; +} + +} // namespace internal +} // namespace protobuf +} // namespace google |