github.com/cockroachdb/pebble@v1.1.2/internal/humanize/humanize.go (about)

     1  // Copyright 2019 The LevelDB-Go and Pebble Authors. All rights reserved. Use
     2  // of this source code is governed by a BSD-style license that can be found in
     3  // the LICENSE file.
     4  
     5  package humanize
     6  
     7  import (
     8  	"fmt"
     9  	"math"
    10  
    11  	"github.com/cockroachdb/redact"
    12  )
    13  
    14  func logn(n, b float64) float64 {
    15  	return math.Log(n) / math.Log(b)
    16  }
    17  
    18  func humanate(s uint64, base float64, suffixes []string) string {
    19  	if s < 10 {
    20  		return fmt.Sprintf("%d%s", s, suffixes[0])
    21  	}
    22  	e := math.Floor(logn(float64(s), base))
    23  	suffix := suffixes[int(e)]
    24  	val := math.Floor(float64(s)/math.Pow(base, e)*10+0.5) / 10
    25  	f := "%.0f%s"
    26  	if val < 10 {
    27  		f = "%.1f%s"
    28  	}
    29  
    30  	return fmt.Sprintf(f, val, suffix)
    31  }
    32  
    33  type config struct {
    34  	base   float64
    35  	suffix []string
    36  }
    37  
    38  // Bytes produces human readable representations of byte values in IEC units.
    39  var Bytes = config{1024, []string{"B", "KB", "MB", "GB", "TB", "PB", "EB"}}
    40  
    41  // Count produces human readable representations of unitless values in SI units.
    42  var Count = config{1000, []string{"", "K", "M", "G", "T", "P", "E"}}
    43  
    44  // Int64 produces a human readable representation of the value.
    45  func (c *config) Int64(s int64) FormattedString {
    46  	if s < 0 {
    47  		return FormattedString("-" + humanate(uint64(-s), c.base, c.suffix))
    48  	}
    49  	return FormattedString(humanate(uint64(s), c.base, c.suffix))
    50  }
    51  
    52  // Uint64 produces a human readable representation of the value.
    53  func (c *config) Uint64(s uint64) FormattedString {
    54  	return FormattedString(humanate(s, c.base, c.suffix))
    55  }
    56  
    57  // FormattedString represents a human readable representation of a value. It
    58  // implements the redact.SafeValue interface to signal that it represents a
    59  // a string that does not need to be redacted.
    60  type FormattedString string
    61  
    62  var _ redact.SafeValue = FormattedString("")
    63  
    64  // SafeValue implements redact.SafeValue.
    65  func (fs FormattedString) SafeValue() {}
    66  
    67  // String implements fmt.Stringer.
    68  func (fs FormattedString) String() string { return string(fs) }