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package testing
import (
"math/rand"
"strings"
"time"
)
func init() {
rand.Seed(time.Now().Unix())
}
const (
letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
letterIdxBits = 6 // 6 bits to represent a letter index
letterIdxMask = 1<<letterIdxBits - 1 // All 1-bits, as many as letterIdxBits
letterIdxMax = 63 / letterIdxBits // Number of letter indices fitting in 63 bits
)
// RandomBytes returns a random byte slice with length n.
func RandomBytes(n int) []byte {
src := rand.NewSource(time.Now().UnixNano())
b := make([]byte, n)
// A src.Int63() generates 63 random bits, enough for letterIdxMax characters
for i, cache, remain := n-1, src.Int63(), letterIdxMax; i >= 0; {
if remain == 0 {
cache, remain = src.Int63(), letterIdxMax
}
if idx := int(cache & letterIdxMask); idx < len(letterBytes) {
b[i] = letterBytes[idx]
i--
}
cache >>= letterIdxBits
remain--
}
return b
}
const (
// MaxPriority contains the maximum priority value that a RFC5424 syslog message can have.
MaxPriority = uint8(191)
// MaxVersion contains the maximum version value that a RFC5424 syslog message can have.
MaxVersion = uint16(999)
// MaxRFC3339MicroTimestamp contains the maximum length RFC3339MICRO timestamp that a RFC5424 syslog message can have.
MaxRFC3339MicroTimestamp = "2018-12-31T23:59:59.999999-23:59"
)
var (
// MaxHostname is a maximum length hostname that a RFC5424 syslog message can have.
MaxHostname = RandomBytes(255)
// MaxAppname is a maximum length app-name that a RFC5424 syslog message can have.
MaxAppname = RandomBytes(48)
// MaxProcID is a maximum length app-name that a RFC5424 syslog message can have.
MaxProcID = RandomBytes(128)
// MaxMsgID is a maximum length app-name that a RFC5424 syslog message can have.
MaxMsgID = RandomBytes(32)
// MaxMessage is a maximum length message that a RFC5424 syslog message can contain when all other fields are at their maximum length.
MaxMessage = RandomBytes(7681)
)
// RightPad pads a string with spaces until the given limit, or it cuts the string to the given limit.
func RightPad(str string, limit int) string {
str = str + strings.Repeat(" ", limit)
return str[:limit]
}
// StringAddress returns the address of the input string.
func StringAddress(str string) *string {
return &str
}
// Uint8Address returns the address of the input uint8.
func Uint8Address(x uint8) *uint8 {
return &x
}
// TimeParse parses a time string, for the given layout, into a pointer to a time.Time instance.
func TimeParse(layout, value string) *time.Time {
t, _ := time.Parse(layout, value)
return &t
}
// YearTime returns a time.Time of the given month, day, hour, minutes, and seconds for the current year (in UTC).
func YearTime(mm, dd, hh, min, ss int) time.Time {
return time.Date(time.Now().Year(), time.Month(mm), dd, hh, min, ss, 0, time.UTC)
}
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