forked from cerc-io/plugeth
ae9f97221a
* go-metrics: fork library and introduce ResettingTimer and InfluxDB reporter. * vendor: change nonsense/go-metrics to ethersphere/go-metrics * go-metrics: add tests. move ResettingTimer logic from reporter to type. * all, metrics: pull in metrics package in go-ethereum * metrics/test: make sure metrics are enabled for tests * metrics: apply gosimple rules * metrics/exp, internal/debug: init expvar endpoint when starting pprof server * internal/debug: tiny comment formatting fix
75 lines
2.3 KiB
Go
75 lines
2.3 KiB
Go
package models
|
|
|
|
// Helper time methods since parsing time can easily overflow and we only support a
|
|
// specific time range.
|
|
|
|
import (
|
|
"fmt"
|
|
"math"
|
|
"time"
|
|
)
|
|
|
|
const (
|
|
// MinNanoTime is the minumum time that can be represented.
|
|
//
|
|
// 1677-09-21 00:12:43.145224194 +0000 UTC
|
|
//
|
|
// The two lowest minimum integers are used as sentinel values. The
|
|
// minimum value needs to be used as a value lower than any other value for
|
|
// comparisons and another separate value is needed to act as a sentinel
|
|
// default value that is unusable by the user, but usable internally.
|
|
// Because these two values need to be used for a special purpose, we do
|
|
// not allow users to write points at these two times.
|
|
MinNanoTime = int64(math.MinInt64) + 2
|
|
|
|
// MaxNanoTime is the maximum time that can be represented.
|
|
//
|
|
// 2262-04-11 23:47:16.854775806 +0000 UTC
|
|
//
|
|
// The highest time represented by a nanosecond needs to be used for an
|
|
// exclusive range in the shard group, so the maximum time needs to be one
|
|
// less than the possible maximum number of nanoseconds representable by an
|
|
// int64 so that we don't lose a point at that one time.
|
|
MaxNanoTime = int64(math.MaxInt64) - 1
|
|
)
|
|
|
|
var (
|
|
minNanoTime = time.Unix(0, MinNanoTime).UTC()
|
|
maxNanoTime = time.Unix(0, MaxNanoTime).UTC()
|
|
|
|
// ErrTimeOutOfRange gets returned when time is out of the representable range using int64 nanoseconds since the epoch.
|
|
ErrTimeOutOfRange = fmt.Errorf("time outside range %d - %d", MinNanoTime, MaxNanoTime)
|
|
)
|
|
|
|
// SafeCalcTime safely calculates the time given. Will return error if the time is outside the
|
|
// supported range.
|
|
func SafeCalcTime(timestamp int64, precision string) (time.Time, error) {
|
|
mult := GetPrecisionMultiplier(precision)
|
|
if t, ok := safeSignedMult(timestamp, mult); ok {
|
|
tme := time.Unix(0, t).UTC()
|
|
return tme, CheckTime(tme)
|
|
}
|
|
|
|
return time.Time{}, ErrTimeOutOfRange
|
|
}
|
|
|
|
// CheckTime checks that a time is within the safe range.
|
|
func CheckTime(t time.Time) error {
|
|
if t.Before(minNanoTime) || t.After(maxNanoTime) {
|
|
return ErrTimeOutOfRange
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// Perform the multiplication and check to make sure it didn't overflow.
|
|
func safeSignedMult(a, b int64) (int64, bool) {
|
|
if a == 0 || b == 0 || a == 1 || b == 1 {
|
|
return a * b, true
|
|
}
|
|
if a == MinNanoTime || b == MaxNanoTime {
|
|
return 0, false
|
|
}
|
|
c := a * b
|
|
return c, c/b == a
|
|
}
|