forked from Shiloh/githaven
106 lines
2.4 KiB
Go
106 lines
2.4 KiB
Go
|
package ber
|
||
|
|
|
||
|
|
import (
|
||
|
|
"bytes"
|
||
|
|
"errors"
|
||
|
|
"fmt"
|
||
|
|
"strconv"
|
||
|
|
"time"
|
||
|
|
)
|
||
|
|
|
||
|
|
// ErrInvalidTimeFormat is returned when the generalizedTime string was not correct.
|
||
|
|
var ErrInvalidTimeFormat = errors.New("invalid time format")
|
||
|
|
|
||
|
|
var zeroTime = time.Time{}
|
||
|
|
|
||
|
|
// ParseGeneralizedTime parses a string value and if it conforms to
|
||
|
|
// GeneralizedTime[^0] format, will return a time.Time for that value.
|
||
|
|
//
|
||
|
|
// [^0]: https://www.itu.int/rec/T-REC-X.690-201508-I/en Section 11.7
|
||
|
|
func ParseGeneralizedTime(v []byte) (time.Time, error) {
|
||
|
|
var format string
|
||
|
|
var fract time.Duration
|
||
|
|
|
||
|
|
str := []byte(DecodeString(v))
|
||
|
|
tzIndex := bytes.IndexAny(str, "Z+-")
|
||
|
|
if tzIndex < 0 {
|
||
|
|
return zeroTime, ErrInvalidTimeFormat
|
||
|
|
}
|
||
|
|
|
||
|
|
dot := bytes.IndexAny(str, ".,")
|
||
|
|
switch dot {
|
||
|
|
case -1:
|
||
|
|
switch tzIndex {
|
||
|
|
case 10:
|
||
|
|
format = `2006010215Z`
|
||
|
|
case 12:
|
||
|
|
format = `200601021504Z`
|
||
|
|
case 14:
|
||
|
|
format = `20060102150405Z`
|
||
|
|
default:
|
||
|
|
return zeroTime, ErrInvalidTimeFormat
|
||
|
|
}
|
||
|
|
|
||
|
|
case 10, 12:
|
||
|
|
if tzIndex < dot {
|
||
|
|
return zeroTime, ErrInvalidTimeFormat
|
||
|
|
}
|
||
|
|
// a "," is also allowed, but would not be parsed by time.Parse():
|
||
|
|
str[dot] = '.'
|
||
|
|
|
||
|
|
// If <minute> is omitted, then <fraction> represents a fraction of an
|
||
|
|
// hour; otherwise, if <second> and <leap-second> are omitted, then
|
||
|
|
// <fraction> represents a fraction of a minute; otherwise, <fraction>
|
||
|
|
// represents a fraction of a second.
|
||
|
|
|
||
|
|
// parse as float from dot to timezone
|
||
|
|
f, err := strconv.ParseFloat(string(str[dot:tzIndex]), 64)
|
||
|
|
if err != nil {
|
||
|
|
return zeroTime, fmt.Errorf("failed to parse float: %s", err)
|
||
|
|
}
|
||
|
|
// ...and strip that part
|
||
|
|
str = append(str[:dot], str[tzIndex:]...)
|
||
|
|
tzIndex = dot
|
||
|
|
|
||
|
|
if dot == 10 {
|
||
|
|
fract = time.Duration(int64(f * float64(time.Hour)))
|
||
|
|
format = `2006010215Z`
|
||
|
|
} else {
|
||
|
|
fract = time.Duration(int64(f * float64(time.Minute)))
|
||
|
|
format = `200601021504Z`
|
||
|
|
}
|
||
|
|
|
||
|
|
case 14:
|
||
|
|
if tzIndex < dot {
|
||
|
|
return zeroTime, ErrInvalidTimeFormat
|
||
|
|
}
|
||
|
|
str[dot] = '.'
|
||
|
|
// no need for fractional seconds, time.Parse() handles that
|
||
|
|
format = `20060102150405Z`
|
||
|
|
|
||
|
|
default:
|
||
|
|
return zeroTime, ErrInvalidTimeFormat
|
||
|
|
}
|
||
|
|
|
||
|
|
l := len(str)
|
||
|
|
switch l - tzIndex {
|
||
|
|
case 1:
|
||
|
|
if str[l-1] != 'Z' {
|
||
|
|
return zeroTime, ErrInvalidTimeFormat
|
||
|
|
}
|
||
|
|
case 3:
|
||
|
|
format += `0700`
|
||
|
|
str = append(str, []byte("00")...)
|
||
|
|
case 5:
|
||
|
|
format += `0700`
|
||
|
|
default:
|
||
|
|
return zeroTime, ErrInvalidTimeFormat
|
||
|
|
}
|
||
|
|
|
||
|
|
t, err := time.Parse(format, string(str))
|
||
|
|
if err != nil {
|
||
|
|
return zeroTime, fmt.Errorf("%s: %s", ErrInvalidTimeFormat, err)
|
||
|
|
}
|
||
|
|
return t.Add(fract), nil
|
||
|
|
}
|