minio/cmd/strconv-bytes.go
Harshavardhana bccf549463 server: Move all the top level files into cmd folder. (#2490)
This change brings a change which was done for the 'mc'
package to allow for clean repo and have a cleaner
github drop in experience.
2016-08-18 16:23:42 -07:00

118 lines
2.5 KiB
Go

/*
* Minio Cloud Storage, (C) 2016 Minio, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package cmd
import (
"fmt"
"math"
"strconv"
"strings"
"unicode"
)
// IEC Sizes, kibis of bits
const (
Byte = 1 << (iota * 10)
KiByte
MiByte
GiByte
TiByte
PiByte
EiByte
)
// Scientific notation Sizes.
const (
IByte = 1
KByte = IByte * 1000
MByte = KByte * 1000
GByte = MByte * 1000
TByte = GByte * 1000
PByte = TByte * 1000
EByte = PByte * 1000
)
// This table represents both IEC and SI notations with their corresponding values.
var bytesSizeTable = map[string]uint64{
"b": Byte,
"kib": KiByte,
"kb": KByte,
"mib": MiByte,
"mb": MByte,
"gib": GiByte,
"gb": GByte,
"tib": TiByte,
"tb": TByte,
"pib": PiByte,
"pb": PByte,
"eib": EiByte,
"eb": EByte,
// Without suffix
"": Byte,
"ki": KiByte,
"k": KByte,
"mi": MiByte,
"m": MByte,
"gi": GiByte,
"g": GByte,
"ti": TiByte,
"t": TByte,
"pi": PiByte,
"p": PByte,
"ei": EiByte,
"e": EByte,
}
// strconvBytes parses a string representation of bytes into the number
// of bytes it represents.
//
// See Also: Bytes, IBytes.
//
// ParseBytes("42MB") -> 42000000, nil
// ParseBytes("42mib") -> 44040192, nil
func strconvBytes(s string) (uint64, error) {
lastDigit := 0
// Calculates the final integer value.
for _, r := range s {
// This supports decimals as well.
if !(unicode.IsDigit(r) || r == '.') {
break
}
lastDigit++
}
// Float parsing to deal with decimal inputs.
f, err := strconv.ParseFloat(s[:lastDigit], 64)
if err != nil {
return 0, err
}
// Fetch the corresponding byte size for notation.
byteSize := strings.ToLower(strings.TrimSpace(s[lastDigit:]))
size, ok := bytesSizeTable[byteSize]
if !ok {
return 0, fmt.Errorf("Unrecognized size notation name: %v", byteSize)
}
f *= float64(size)
// Return an error if final value overflows uint64 max.
if f >= math.MaxUint64 {
return 0, fmt.Errorf("too large: %v", s)
}
// Success.
return uint64(f), nil
}