vendor/github.com/aws/aws-sdk-go/internal/ini/number_helper.go

   1 package ini
   2
   3 import (
   4         "bytes"
   5         "fmt"
   6         "strconv"
   7 )
   8
   9 const (
  10         none = numberFormat(iota)
  11         binary
  12         octal
  13         decimal
  14         hex
  15         exponent
  16 )
  17
  18 type numberFormat int
  19
  20 // numberHelper is used to dictate what format a number is in
  21 // and what to do for negative values. Since -1e-4 is a valid
  22 // number, we cannot just simply check for duplicate negatives.
  23 type numberHelper struct {
  24         numberFormat numberFormat
  25
  26         negative         bool
  27         negativeExponent bool
  28 }
  29
  30 func (b numberHelper) Exists() bool {
  31         return b.numberFormat != none
  32 }
  33
  34 func (b numberHelper) IsNegative() bool {
  35         return b.negative || b.negativeExponent
  36 }
  37
  38 func (b *numberHelper) Determine(c rune) error {
  39         if b.Exists() {
  40                 return NewParseError(fmt.Sprintf("multiple number formats: 0%v", string(c)))
  41         }
  42
  43         switch c {
  44         case 'b':
  45                 b.numberFormat = binary
  46         case 'o':
  47                 b.numberFormat = octal
  48         case 'x':
  49                 b.numberFormat = hex
  50         case 'e', 'E':
  51                 b.numberFormat = exponent
  52         case '-':
  53                 if b.numberFormat != exponent {
  54                         b.negative = true
  55                 } else {
  56                         b.negativeExponent = true
  57                 }
  58         case '.':
  59                 b.numberFormat = decimal
  60         default:
  61                 return NewParseError(fmt.Sprintf("invalid number character: %v", string(c)))
  62         }
  63
  64         return nil
  65 }
  66
  67 func (b numberHelper) CorrectByte(c rune) bool {
  68         switch {
  69         case b.numberFormat == binary:
  70                 if !isBinaryByte(c) {
  71                         return false
  72                 }
  73         case b.numberFormat == octal:
  74                 if !isOctalByte(c) {
  75                         return false
  76                 }
  77         case b.numberFormat == hex:
  78                 if !isHexByte(c) {
  79                         return false
  80                 }
  81         case b.numberFormat == decimal:
  82                 if !isDigit(c) {
  83                         return false
  84                 }
  85         case b.numberFormat == exponent:
  86                 if !isDigit(c) {
  87                         return false
  88                 }
  89         case b.negativeExponent:
  90                 if !isDigit(c) {
  91                         return false
  92                 }
  93         case b.negative:
  94                 if !isDigit(c) {
  95                         return false
  96                 }
  97         default:
  98                 if !isDigit(c) {
  99                         return false
 100                 }
 101         }
 102
 103         return true
 104 }
 105
 106 func (b numberHelper) Base() int {
 107         switch b.numberFormat {
 108         case binary:
 109                 return 2
 110         case octal:
 111                 return 8
 112         case hex:
 113                 return 16
 114         default:
 115                 return 10
 116         }
 117 }
 118
 119 func (b numberHelper) String() string {
 120         buf := bytes.Buffer{}
 121         i := 0
 122
 123         switch b.numberFormat {
 124         case binary:
 125                 i++
 126                 buf.WriteString(strconv.Itoa(i) + ": binary format\n")
 127         case octal:
 128                 i++
 129                 buf.WriteString(strconv.Itoa(i) + ": octal format\n")
 130         case hex:
 131                 i++
 132                 buf.WriteString(strconv.Itoa(i) + ": hex format\n")
 133         case exponent:
 134                 i++
 135                 buf.WriteString(strconv.Itoa(i) + ": exponent format\n")
 136         default:
 137                 i++
 138                 buf.WriteString(strconv.Itoa(i) + ": integer format\n")
 139         }
 140
 141         if b.negative {
 142                 i++
 143                 buf.WriteString(strconv.Itoa(i) + ": negative format\n")
 144         }
 145
 146         if b.negativeExponent {
 147                 i++
 148                 buf.WriteString(strconv.Itoa(i) + ": negative exponent format\n")
 149         }
 150
 151         return buf.String()
 152 }