diff options
Diffstat (limited to 'vendor/github.com/docker/go-units/size.go')
-rw-r--r-- | vendor/github.com/docker/go-units/size.go | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/vendor/github.com/docker/go-units/size.go b/vendor/github.com/docker/go-units/size.go new file mode 100644 index 000000000..f5b82ea24 --- /dev/null +++ b/vendor/github.com/docker/go-units/size.go @@ -0,0 +1,96 @@ +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"} + +// CustomSize returns a human-readable approximation of a size +// using custom format. +func CustomSize(format string, size float64, base float64, _map []string) string { + i := 0 + unitsLimit := len(_map) - 1 + for size >= base && i < unitsLimit { + size = size / base + i++ + } + return fmt.Sprintf(format, size, _map[i]) +} + +// 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 CustomSize("%.4g %s", size, 1000.0, decimapAbbrs) +} + +// 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 +} |