github.com/cockroachdb/cockroachdb-parser@v0.23.3-0.20240213214944-911057d40c9a/pkg/util/humanizeutil/humanize.go

// 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/cockroachdb/errors"
	"github.com/cockroachdb/redact"
	"github.com/dustin/go-humanize"
	"github.com/spf13/pflag"
)

// IBytes is an int64 version of go-humanize's IBytes.
func IBytes(value int64) redact.SafeString {
	if value < 0 {
		return redact.SafeString("-" + humanize.IBytes(uint64(-value)))
	}
	return redact.SafeString(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, errors.New("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, errors.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
	}
	if b.val == nil {
		b.val = new(int64)
	}
	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 {
	return redact.StringWithoutMarkers(b)
}

// SafeFormat implements the redact.SafeFormatter interface.
func (b *BytesValue) SafeFormat(w redact.SafePrinter, _ rune) {
	// When b.val is nil, the real value of the flag will only be known after a
	// Resolve() call. We do not want our flag package to report an erroneous
	// default value for this flag. So the value we return here must cause
	// defaultIsZeroValue to return true:
	// https://github.com/spf13/pflag/blob/v1.0.5/flag.go#L724
	if b.val == nil {
		w.SafeString("<nil>")
		return
	}
	// 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.
	w.Print(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) redact.SafeString {
	if bytes == 0 {
		return "0"
	}
	if elapsed == 0 {
		return "inf"
	}
	return redact.SafeString(fmt.Sprintf("%0.2f MiB/s",
		(float64(bytes)/elapsed.Seconds())/float64(1<<20)))
}