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// Copyright 2016 The Cockroach Authors.
//
// Use of this software is governed by the Business Source License
// included in the file licenses/BSL.txt.
//
// As of the Change Date specified in that file, in accordance with
// the Business Source License, use of this software will be governed
// by the Apache License, Version 2.0, included in the file
// licenses/APL.txt.
package humanizeutil
import (
"flag"
"fmt"
"math"
"sync/atomic"
"time"
"github.com/dustin/go-humanize"
"github.com/spf13/pflag"
)
// IBytes is an int64 version of go-humanize's IBytes.
func IBytes(value int64) string {
if value < 0 {
return fmt.Sprintf("-%s", humanize.IBytes(uint64(-value)))
}
return humanize.IBytes(uint64(value))
}
// ParseBytes is an int64 version of go-humanize's ParseBytes.
func ParseBytes(s string) (int64, error) {
if len(s) == 0 {
return 0, fmt.Errorf("parsing \"\": invalid syntax")
}
var startIndex int
var negative bool
if s[0] == '-' {
negative = true
startIndex = 1
}
value, err := humanize.ParseBytes(s[startIndex:])
if err != nil {
return 0, err
}
if value > math.MaxInt64 {
return 0, fmt.Errorf("too large: %s", s)
}
if negative {
return -int64(value), nil
}
return int64(value), nil
}
// BytesValue is a struct that implements flag.Value and pflag.Value
// suitable to create command-line parameters that accept sizes
// specified using a format recognized by humanize.
// The value is written atomically, so that it is safe to use this
// struct to make a parameter configurable that is used by an
// asynchronous process spawned before command-line argument handling.
// This is useful e.g. for the log file settings which are used
// by the asynchronous log file GC daemon.
type BytesValue struct {
val *int64
isSet bool
}
var _ flag.Value = &BytesValue{}
var _ pflag.Value = &BytesValue{}
// NewBytesValue creates a new pflag.Value bound to the specified
// int64 variable. It also happens to be a flag.Value.
func NewBytesValue(val *int64) *BytesValue {
return &BytesValue{val: val}
}
// Set implements the flag.Value and pflag.Value interfaces.
func (b *BytesValue) Set(s string) error {
v, err := ParseBytes(s)
if err != nil {
return err
}
atomic.StoreInt64(b.val, v)
b.isSet = true
return nil
}
// Type implements the pflag.Value interface.
func (b *BytesValue) Type() string {
return "bytes"
}
// String implements the flag.Value and pflag.Value interfaces.
func (b *BytesValue) String() string {
// We need to be able to print the zero value in order for go's flags
// package to not choke when comparing values to the zero value,
// as it does in isZeroValue as of go1.8:
// https://github.com/golang/go/blob/release-branch.go1.8/src/flag/flag.go#L384
if b.val == nil {
return IBytes(0)
}
// This uses the MiB, GiB, etc suffixes. If we use humanize.Bytes() we get
// the MB, GB, etc suffixes, but the conversion is done in multiples of 1000
// vs 1024.
return IBytes(atomic.LoadInt64(b.val))
}
// IsSet returns true iff Set has successfully been called.
func (b *BytesValue) IsSet() bool {
return b.isSet
}
// DataRate formats the passed byte count over duration as "x MiB/s".
func DataRate(bytes int64, elapsed time.Duration) string {
if bytes == 0 {
return "0"
}
if elapsed == 0 {
return "inf"
}
return fmt.Sprintf("%0.2f MiB/s", (float64(bytes)/elapsed.Seconds())/float64(1<<20))
}
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