rclone/fs/sizesuffix.go
Nick Craig-Wood 11da2a6c9b Break the fs package up into smaller parts.
The purpose of this is to make it easier to maintain and eventually to
allow the rclone backends to be re-used in other projects without
having to use the rclone configuration system.

The new code layout is documented in CONTRIBUTING.
2018-01-15 17:51:14 +00:00

103 lines
2.0 KiB
Go

package fs
// SizeSuffix is parsed by flag with k/M/G suffixes
import (
"fmt"
"math"
"strconv"
"strings"
"github.com/pkg/errors"
)
// SizeSuffix is an int64 with a friendly way of printing setting
type SizeSuffix int64
// Turn SizeSuffix into a string and a suffix
func (x SizeSuffix) string() (string, string) {
scaled := float64(0)
suffix := ""
switch {
case x < 0:
return "off", ""
case x == 0:
return "0", ""
case x < 1024:
scaled = float64(x)
suffix = ""
case x < 1024*1024:
scaled = float64(x) / 1024
suffix = "k"
case x < 1024*1024*1024:
scaled = float64(x) / 1024 / 1024
suffix = "M"
default:
scaled = float64(x) / 1024 / 1024 / 1024
suffix = "G"
}
if math.Floor(scaled) == scaled {
return fmt.Sprintf("%.0f", scaled), suffix
}
return fmt.Sprintf("%.3f", scaled), suffix
}
// String turns SizeSuffix into a string
func (x SizeSuffix) String() string {
val, suffix := x.string()
return val + suffix
}
// Unit turns SizeSuffix into a string with a unit
func (x SizeSuffix) Unit(unit string) string {
val, suffix := x.string()
if val == "off" {
return val
}
return val + " " + suffix + unit
}
// Set a SizeSuffix
func (x *SizeSuffix) Set(s string) error {
if len(s) == 0 {
return errors.New("empty string")
}
if strings.ToLower(s) == "off" {
*x = -1
return nil
}
suffix := s[len(s)-1]
suffixLen := 1
var multiplier float64
switch suffix {
case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '.':
suffixLen = 0
multiplier = 1 << 10
case 'b', 'B':
multiplier = 1
case 'k', 'K':
multiplier = 1 << 10
case 'm', 'M':
multiplier = 1 << 20
case 'g', 'G':
multiplier = 1 << 30
default:
return errors.Errorf("bad suffix %q", suffix)
}
s = s[:len(s)-suffixLen]
value, err := strconv.ParseFloat(s, 64)
if err != nil {
return err
}
if value < 0 {
return errors.Errorf("size can't be negative %q", s)
}
value *= multiplier
*x = SizeSuffix(value)
return nil
}
// Type of the value
func (x *SizeSuffix) Type() string {
return "int64"
}