syncthing/lib/config/size.go

119 lines
2.6 KiB
Go

// Copyright (C) 2017 The Syncthing Authors.
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this file,
// You can obtain one at https://mozilla.org/MPL/2.0/.
package config
import (
"fmt"
"strconv"
"strings"
"github.com/syncthing/syncthing/lib/fs"
)
func ParseSize(s string) (Size, error) {
s = strings.TrimSpace(s)
if len(s) == 0 {
return Size{}, nil
}
var num, unit string
for i := 0; i < len(s) && (s[i] >= '0' && s[i] <= '9' || s[i] == '.' || s[i] == ','); i++ {
num = s[:i+1]
}
var i = len(num)
for i < len(s) && s[i] == ' ' {
i++
}
unit = s[i:]
val, err := strconv.ParseFloat(num, 64)
if err != nil {
return Size{}, err
}
return Size{val, unit}, nil
}
func (s Size) BaseValue() float64 {
unitPrefix := s.Unit
if len(unitPrefix) > 1 {
unitPrefix = unitPrefix[:1]
}
mult := 1.0
switch unitPrefix {
case "k", "K":
mult = 1000
case "m", "M":
mult = 1000 * 1000
case "g", "G":
mult = 1000 * 1000 * 1000
case "t", "T":
mult = 1000 * 1000 * 1000 * 1000
}
return s.Value * mult
}
func (s Size) Percentage() bool {
return strings.Contains(s.Unit, "%")
}
func (s Size) String() string {
return fmt.Sprintf("%v %s", s.Value, s.Unit)
}
func (s *Size) ParseDefault(str string) error {
sz, err := ParseSize(str)
*s = sz
return err
}
// CheckFreeSpace checks that the free space does not fall below the minimum required free space.
func CheckFreeSpace(minFree Size, usage fs.Usage) error {
val := minFree.BaseValue()
if val <= 0 {
return nil
}
if minFree.Percentage() {
freePct := (float64(usage.Free) / float64(usage.Total)) * 100
if freePct < val {
return fmt.Errorf("%.1f %% < %v", freePct, minFree)
}
} else if float64(usage.Free) < val {
return fmt.Errorf("%sB < %v", formatSI(usage.Free), minFree)
}
return nil
}
// checkAvailableSpace checks that the free space does not fall below the minimum
// required free space, considering additional required space for a future operation.
func checkAvailableSpace(req uint64, minFree Size, usage fs.Usage) bool {
if usage.Free < req {
return false
}
usage.Free -= req
return CheckFreeSpace(minFree, usage) == nil
}
func formatSI(b uint64) string {
switch {
case b < 1000:
return fmt.Sprintf("%d ", b)
case b < 1000*1000:
return fmt.Sprintf("%.1f K", float64(b)/1000)
case b < 1000*1000*1000:
return fmt.Sprintf("%.1f M", float64(b)/(1000*1000))
case b < 1000*1000*1000*1000:
return fmt.Sprintf("%.1f G", float64(b)/(1000*1000*1000))
default:
return fmt.Sprintf("%.1f T", float64(b)/(1000*1000*1000*1000))
}
}