109 lines
2.9 KiB
Go
109 lines
2.9 KiB
Go
|
package units
|
||
|
|
|
||
|
|
import (
|
||
|
|
"fmt"
|
||
|
|
"regexp"
|
||
|
|
"strconv"
|
||
|
|
"strings"
|
||
|
|
)
|
||
|
|
|
||
|
|
// See: http://en.wikipedia.org/wiki/Binary_prefix
|
||
|
|
const (
|
||
|
|
// Decimal
|
||
|
|
|
||
|
|
KB = 1000
|
||
|
|
MB = 1000 * KB
|
||
|
|
GB = 1000 * MB
|
||
|
|
TB = 1000 * GB
|
||
|
|
PB = 1000 * TB
|
||
|
|
|
||
|
|
// Binary
|
||
|
|
|
||
|
|
KiB = 1024
|
||
|
|
MiB = 1024 * KiB
|
||
|
|
GiB = 1024 * MiB
|
||
|
|
TiB = 1024 * GiB
|
||
|
|
PiB = 1024 * TiB
|
||
|
|
)
|
||
|
|
|
||
|
|
type unitMap map[string]int64
|
||
|
|
|
||
|
|
var (
|
||
|
|
decimalMap = unitMap{"k": KB, "m": MB, "g": GB, "t": TB, "p": PB}
|
||
|
|
binaryMap = unitMap{"k": KiB, "m": MiB, "g": GiB, "t": TiB, "p": PiB}
|
||
|
|
sizeRegex = regexp.MustCompile(`^(\d+(\.\d+)*) ?([kKmMgGtTpP])?[bB]?$`)
|
||
|
|
)
|
||
|
|
|
||
|
|
var decimapAbbrs = []string{"B", "kB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB"}
|
||
|
|
var binaryAbbrs = []string{"B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB", "ZiB", "YiB"}
|
||
|
|
|
||
|
|
func getSizeAndUnit(size float64, base float64, _map []string) (float64, string) {
|
||
|
|
i := 0
|
||
|
|
unitsLimit := len(_map) - 1
|
||
|
|
for size >= base && i < unitsLimit {
|
||
|
|
size = size / base
|
||
|
|
i++
|
||
|
|
}
|
||
|
|
return size, _map[i]
|
||
|
|
}
|
||
|
|
|
||
|
|
// CustomSize returns a human-readable approximation of a size
|
||
|
|
// using custom format.
|
||
|
|
func CustomSize(format string, size float64, base float64, _map []string) string {
|
||
|
|
size, unit := getSizeAndUnit(size, base, _map)
|
||
|
|
return fmt.Sprintf(format, size, unit)
|
||
|
|
}
|
||
|
|
|
||
|
|
// HumanSizeWithPrecision allows the size to be in any precision,
|
||
|
|
// instead of 4 digit precision used in units.HumanSize.
|
||
|
|
func HumanSizeWithPrecision(size float64, precision int) string {
|
||
|
|
size, unit := getSizeAndUnit(size, 1000.0, decimapAbbrs)
|
||
|
|
return fmt.Sprintf("%.*g%s", precision, size, unit)
|
||
|
|
}
|
||
|
|
|
||
|
|
// HumanSize returns a human-readable approximation of a size
|
||
|
|
// capped at 4 valid numbers (eg. "2.746 MB", "796 KB").
|
||
|
|
func HumanSize(size float64) string {
|
||
|
|
return HumanSizeWithPrecision(size, 4)
|
||
|
|
}
|
||
|
|
|
||
|
|
// BytesSize returns a human-readable size in bytes, kibibytes,
|
||
|
|
// mebibytes, gibibytes, or tebibytes (eg. "44kiB", "17MiB").
|
||
|
|
func BytesSize(size float64) string {
|
||
|
|
return CustomSize("%.4g%s", size, 1024.0, binaryAbbrs)
|
||
|
|
}
|
||
|
|
|
||
|
|
// FromHumanSize returns an integer from a human-readable specification of a
|
||
|
|
// size using SI standard (eg. "44kB", "17MB").
|
||
|
|
func FromHumanSize(size string) (int64, error) {
|
||
|
|
return parseSize(size, decimalMap)
|
||
|
|
}
|
||
|
|
|
||
|
|
// RAMInBytes parses a human-readable string representing an amount of RAM
|
||
|
|
// in bytes, kibibytes, mebibytes, gibibytes, or tebibytes and
|
||
|
|
// returns the number of bytes, or -1 if the string is unparseable.
|
||
|
|
// Units are case-insensitive, and the 'b' suffix is optional.
|
||
|
|
func RAMInBytes(size string) (int64, error) {
|
||
|
|
return parseSize(size, binaryMap)
|
||
|
|
}
|
||
|
|
|
||
|
|
// Parses the human-readable size string into the amount it represents.
|
||
|
|
func parseSize(sizeStr string, uMap unitMap) (int64, error) {
|
||
|
|
matches := sizeRegex.FindStringSubmatch(sizeStr)
|
||
|
|
if len(matches) != 4 {
|
||
|
|
return -1, fmt.Errorf("invalid size: '%s'", sizeStr)
|
||
|
|
}
|
||
|
|
|
||
|
|
size, err := strconv.ParseFloat(matches[1], 64)
|
||
|
|
if err != nil {
|
||
|
|
return -1, err
|
||
|
|
}
|
||
|
|
|
||
|
|
unitPrefix := strings.ToLower(matches[3])
|
||
|
|
if mul, ok := uMap[unitPrefix]; ok {
|
||
|
|
size *= float64(mul)
|
||
|
|
}
|
||
|
|
|
||
|
|
return int64(size), nil
|
||
|
|
}
|