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log/colors.go
Andrew Thornton f316138381
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stylistic-fixes (#17)
2019-12-08 18:32:19 +00:00

429 lines
10 KiB
Go

// Copyright 2019 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package log
import (
"fmt"
"io"
"reflect"
"strconv"
"strings"
)
const escape = "\033"
// ColorAttribute defines a single SGR Code
type ColorAttribute int
// Base ColorAttributes
const (
Reset ColorAttribute = iota
Bold
Faint
Italic
Underline
BlinkSlow
BlinkRapid
ReverseVideo
Concealed
CrossedOut
)
// Foreground text colors
const (
FgBlack ColorAttribute = iota + 30
FgRed
FgGreen
FgYellow
FgBlue
FgMagenta
FgCyan
FgWhite
)
// Foreground Hi-Intensity text colors
const (
FgHiBlack ColorAttribute = iota + 90
FgHiRed
FgHiGreen
FgHiYellow
FgHiBlue
FgHiMagenta
FgHiCyan
FgHiWhite
)
// Background text colors
const (
BgBlack ColorAttribute = iota + 40
BgRed
BgGreen
BgYellow
BgBlue
BgMagenta
BgCyan
BgWhite
)
// Background Hi-Intensity text colors
const (
BgHiBlack ColorAttribute = iota + 100
BgHiRed
BgHiGreen
BgHiYellow
BgHiBlue
BgHiMagenta
BgHiCyan
BgHiWhite
)
var colorAttributeToString = map[ColorAttribute]string{
Reset: "Reset",
Bold: "Bold",
Faint: "Faint",
Italic: "Italic",
Underline: "Underline",
BlinkSlow: "BlinkSlow",
BlinkRapid: "BlinkRapid",
ReverseVideo: "ReverseVideo",
Concealed: "Concealed",
CrossedOut: "CrossedOut",
FgBlack: "FgBlack",
FgRed: "FgRed",
FgGreen: "FgGreen",
FgYellow: "FgYellow",
FgBlue: "FgBlue",
FgMagenta: "FgMagenta",
FgCyan: "FgCyan",
FgWhite: "FgWhite",
FgHiBlack: "FgHiBlack",
FgHiRed: "FgHiRed",
FgHiGreen: "FgHiGreen",
FgHiYellow: "FgHiYellow",
FgHiBlue: "FgHiBlue",
FgHiMagenta: "FgHiMagenta",
FgHiCyan: "FgHiCyan",
FgHiWhite: "FgHiWhite",
BgBlack: "BgBlack",
BgRed: "BgRed",
BgGreen: "BgGreen",
BgYellow: "BgYellow",
BgBlue: "BgBlue",
BgMagenta: "BgMagenta",
BgCyan: "BgCyan",
BgWhite: "BgWhite",
BgHiBlack: "BgHiBlack",
BgHiRed: "BgHiRed",
BgHiGreen: "BgHiGreen",
BgHiYellow: "BgHiYellow",
BgHiBlue: "BgHiBlue",
BgHiMagenta: "BgHiMagenta",
BgHiCyan: "BgHiCyan",
BgHiWhite: "BgHiWhite",
}
func (c *ColorAttribute) String() string {
return colorAttributeToString[*c]
}
var colorAttributeFromString = map[string]ColorAttribute{}
// ColorAttributeFromString will return a ColorAttribute given a string
func ColorAttributeFromString(from string) ColorAttribute {
lowerFrom := strings.TrimSpace(strings.ToLower(from))
return colorAttributeFromString[lowerFrom]
}
// ColorString converts a list of ColorAttributes to a color string
func ColorString(attrs ...ColorAttribute) string {
return string(ColorBytes(attrs...))
}
// ColorBytes converts a list of ColorAttributes to a byte array
func ColorBytes(attrs ...ColorAttribute) []byte {
bytes := make([]byte, 0, 20)
bytes = append(bytes, escape[0], '[')
if len(attrs) > 0 {
bytes = append(bytes, strconv.Itoa(int(attrs[0]))...)
for _, a := range attrs[1:] {
bytes = append(bytes, ';')
bytes = append(bytes, strconv.Itoa(int(a))...)
}
} else {
bytes = append(bytes, strconv.Itoa(int(Bold))...)
}
bytes = append(bytes, 'm')
return bytes
}
var levelToColor = map[Level]string{
TRACE: ColorString(Bold, FgCyan),
DEBUG: ColorString(Bold, FgBlue),
INFO: ColorString(Bold, FgGreen),
WARN: ColorString(Bold, FgYellow),
ERROR: ColorString(Bold, FgRed),
CRITICAL: ColorString(Bold, BgMagenta),
FATAL: ColorString(Bold, BgRed),
NONE: ColorString(Reset),
}
var resetBytes = ColorBytes(Reset)
var fgCyanBytes = ColorBytes(FgCyan)
var fgGreenBytes = ColorBytes(FgGreen)
var fgBoldBytes = ColorBytes(Bold)
type protectedANSIWriterMode int
const (
escapeAll protectedANSIWriterMode = iota
allowColor
removeColor
)
type protectedANSIWriter struct {
w io.Writer
mode protectedANSIWriterMode
}
// Write will protect against unusual characters
func (c *protectedANSIWriter) Write(bytes []byte) (int, error) {
end := len(bytes)
totalWritten := 0
normalLoop:
for i := 0; i < end; {
lasti := i
if c.mode == escapeAll {
for i < end && (bytes[i] >= ' ' || bytes[i] == '\n' || bytes[i] == '\t') {
i++
}
} else {
// Allow tabs if we're not escaping everything
for i < end && (bytes[i] >= ' ' || bytes[i] == '\t') {
i++
}
}
if i > lasti {
written, err := c.w.Write(bytes[lasti:i])
totalWritten += written
if err != nil {
return totalWritten, err
}
}
if i >= end {
break
}
// If we're not just escaping all we should prefix all newlines with a \t
if c.mode != escapeAll {
if bytes[i] == '\n' {
written, err := c.w.Write([]byte{'\n', '\t'})
if written > 0 {
totalWritten++
}
if err != nil {
return totalWritten, err
}
i++
continue normalLoop
}
if bytes[i] == escape[0] && i+1 < end && bytes[i+1] == '[' {
for j := i + 2; j < end; j++ {
if bytes[j] >= '0' && bytes[j] <= '9' {
continue
}
if bytes[j] == ';' {
continue
}
if bytes[j] == 'm' {
if c.mode == allowColor {
written, err := c.w.Write(bytes[i : j+1])
totalWritten += written
if err != nil {
return totalWritten, err
}
} else {
totalWritten = j
}
i = j + 1
continue normalLoop
}
break
}
}
}
// Process naughty character
if _, err := fmt.Fprintf(c.w, `\%#o03d`, bytes[i]); err != nil {
return totalWritten, err
}
i++
totalWritten++
}
return totalWritten, nil
}
// ColorSprintf returns a colored string from a format and arguments
// arguments will be wrapped in ColoredValues to protect against color spoofing
func ColorSprintf(format string, args ...interface{}) string {
if len(args) > 0 {
v := make([]interface{}, len(args))
for i := 0; i < len(v); i++ {
v[i] = NewColoredValuePointer(&args[i])
}
return fmt.Sprintf(format, v...)
}
return format
}
// ColorFprintf will write to the provided writer similar to ColorSprintf
func ColorFprintf(w io.Writer, format string, args ...interface{}) (int, error) {
if len(args) > 0 {
v := make([]interface{}, len(args))
for i := 0; i < len(v); i++ {
v[i] = NewColoredValuePointer(&args[i])
}
return fmt.Fprintf(w, format, v...)
}
return fmt.Fprint(w, format)
}
// ColorFormatted structs provide their own colored string when formatted with ColorSprintf
type ColorFormatted interface {
// ColorFormat provides the colored representation of the value
ColorFormat(s fmt.State)
}
var colorFormattedType = reflect.TypeOf((*ColorFormatted)(nil)).Elem()
// ColoredValue will Color the provided value
type ColoredValue struct {
colorBytes *[]byte
resetBytes *[]byte
Value *interface{}
}
// NewColoredValue is a helper function to create a ColoredValue from a Value
// If no color is provided it defaults to Bold with standard Reset
// If a ColoredValue is provided it is not changed
func NewColoredValue(value interface{}, color ...ColorAttribute) *ColoredValue {
return NewColoredValuePointer(&value, color...)
}
// NewColoredValuePointer is a helper function to create a ColoredValue from a Value Pointer
// If no color is provided it defaults to Bold with standard Reset
// If a ColoredValue is provided it is not changed
func NewColoredValuePointer(value *interface{}, color ...ColorAttribute) *ColoredValue {
if val, ok := (*value).(*ColoredValue); ok {
return val
}
if len(color) > 0 {
bytes := ColorBytes(color...)
return &ColoredValue{
colorBytes: &bytes,
resetBytes: &resetBytes,
Value: value,
}
}
return &ColoredValue{
colorBytes: &fgBoldBytes,
resetBytes: &resetBytes,
Value: value,
}
}
// NewColoredValueBytes creates a value from the provided value with color bytes
// If a ColoredValue is provided it is not changed
func NewColoredValueBytes(value interface{}, colorBytes *[]byte) *ColoredValue {
if val, ok := value.(*ColoredValue); ok {
return val
}
return &ColoredValue{
colorBytes: colorBytes,
resetBytes: &resetBytes,
Value: &value,
}
}
// NewColoredIDValue is a helper function to create a ColoredValue from a Value
// The Value will be colored with FgCyan
// If a ColoredValue is provided it is not changed
func NewColoredIDValue(value interface{}) *ColoredValue {
return NewColoredValueBytes(&value, &fgCyanBytes)
}
// Format will format the provided value and protect against ANSI color spoofing within the value
// If the wrapped value is ColorFormatted and the format is "%-v" then its ColorString will
// be used. It is presumed that this ColorString is safe.
func (cv *ColoredValue) Format(s fmt.State, c rune) {
if c == 'v' && s.Flag('-') {
if val, ok := (*cv.Value).(ColorFormatted); ok {
val.ColorFormat(s)
return
}
v := reflect.ValueOf(*cv.Value)
t := v.Type()
if reflect.PtrTo(t).Implements(colorFormattedType) {
vp := reflect.New(t)
vp.Elem().Set(v)
val := vp.Interface().(ColorFormatted)
val.ColorFormat(s)
return
}
}
s.Write(*cv.colorBytes)
fmt.Fprintf(&protectedANSIWriter{w: s}, fmtString(s, c), *(cv.Value))
s.Write(*cv.resetBytes)
}
// SetColorBytes will allow a user to set the colorBytes of a colored value
func (cv *ColoredValue) SetColorBytes(colorBytes []byte) {
cv.colorBytes = &colorBytes
}
// SetColorBytesPointer will allow a user to set the colorBytes pointer of a colored value
func (cv *ColoredValue) SetColorBytesPointer(colorBytes *[]byte) {
cv.colorBytes = colorBytes
}
// SetResetBytes will allow a user to set the resetBytes pointer of a colored value
func (cv *ColoredValue) SetResetBytes(resetBytes []byte) {
cv.resetBytes = &resetBytes
}
// SetResetBytesPointer will allow a user to set the resetBytes pointer of a colored value
func (cv *ColoredValue) SetResetBytesPointer(resetBytes *[]byte) {
cv.resetBytes = resetBytes
}
func fmtString(s fmt.State, c rune) string {
var width, precision string
base := make([]byte, 0, 8)
base = append(base, '%')
for _, c := range []byte(" +-#0") {
if s.Flag(int(c)) {
base = append(base, c)
}
}
if w, ok := s.Width(); ok {
width = strconv.Itoa(w)
}
if p, ok := s.Precision(); ok {
precision = "." + strconv.Itoa(p)
}
return fmt.Sprintf("%s%s%s%c", base, width, precision, c)
}
func init() {
for attr, from := range colorAttributeToString {
colorAttributeFromString[strings.ToLower(from)] = attr
}
}