898 lines
25 KiB
Go
898 lines
25 KiB
Go
// Package util provides utility functions for the goldmark.
|
|
package util
|
|
|
|
import (
|
|
"bytes"
|
|
"io"
|
|
"net/url"
|
|
"regexp"
|
|
"sort"
|
|
"strconv"
|
|
"strings"
|
|
"unicode/utf8"
|
|
)
|
|
|
|
// A CopyOnWriteBuffer is a byte buffer that copies buffer when
|
|
// it need to be changed.
|
|
type CopyOnWriteBuffer struct {
|
|
buffer []byte
|
|
copied bool
|
|
}
|
|
|
|
// NewCopyOnWriteBuffer returns a new CopyOnWriteBuffer.
|
|
func NewCopyOnWriteBuffer(buffer []byte) CopyOnWriteBuffer {
|
|
return CopyOnWriteBuffer{
|
|
buffer: buffer,
|
|
copied: false,
|
|
}
|
|
}
|
|
|
|
// Write writes given bytes to the buffer.
|
|
func (b *CopyOnWriteBuffer) Write(value []byte) {
|
|
if !b.copied {
|
|
b.buffer = make([]byte, 0, len(b.buffer)+20)
|
|
b.copied = true
|
|
}
|
|
b.buffer = append(b.buffer, value...)
|
|
}
|
|
|
|
// WriteByte writes the given byte to the buffer.
|
|
func (b *CopyOnWriteBuffer) WriteByte(c byte) {
|
|
if !b.copied {
|
|
b.buffer = make([]byte, 0, len(b.buffer)+20)
|
|
b.copied = true
|
|
}
|
|
b.buffer = append(b.buffer, c)
|
|
}
|
|
|
|
// Bytes returns bytes of this buffer.
|
|
func (b *CopyOnWriteBuffer) Bytes() []byte {
|
|
return b.buffer
|
|
}
|
|
|
|
// IsCopied returns true if buffer has been copied, otherwise false.
|
|
func (b *CopyOnWriteBuffer) IsCopied() bool {
|
|
return b.copied
|
|
}
|
|
|
|
// IsEscapedPunctuation returns true if caracter at a given index i
|
|
// is an escaped punctuation, otherwise false.
|
|
func IsEscapedPunctuation(source []byte, i int) bool {
|
|
return source[i] == '\\' && i < len(source)-1 && IsPunct(source[i+1])
|
|
}
|
|
|
|
// ReadWhile read the given source while pred is true.
|
|
func ReadWhile(source []byte, index [2]int, pred func(byte) bool) (int, bool) {
|
|
j := index[0]
|
|
ok := false
|
|
for ; j < index[1]; j++ {
|
|
c1 := source[j]
|
|
if pred(c1) {
|
|
ok = true
|
|
continue
|
|
}
|
|
break
|
|
}
|
|
return j, ok
|
|
}
|
|
|
|
// IsBlank returns true if the given string is all space characters.
|
|
func IsBlank(bs []byte) bool {
|
|
for _, b := range bs {
|
|
if !IsSpace(b) {
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
}
|
|
|
|
// VisualizeSpaces visualize invisible space characters.
|
|
func VisualizeSpaces(bs []byte) []byte {
|
|
bs = bytes.Replace(bs, []byte(" "), []byte("[SPACE]"), -1)
|
|
bs = bytes.Replace(bs, []byte("\t"), []byte("[TAB]"), -1)
|
|
bs = bytes.Replace(bs, []byte("\n"), []byte("[NEWLINE]\n"), -1)
|
|
bs = bytes.Replace(bs, []byte("\r"), []byte("[CR]"), -1)
|
|
return bs
|
|
}
|
|
|
|
// TabWidth calculates actual width of a tab at the given position.
|
|
func TabWidth(currentPos int) int {
|
|
return 4 - currentPos%4
|
|
}
|
|
|
|
// IndentPosition searches an indent position with the given width for the given line.
|
|
// If the line contains tab characters, paddings may be not zero.
|
|
// currentPos==0 and width==2:
|
|
//
|
|
// position: 0 1
|
|
// [TAB]aaaa
|
|
// width: 1234 5678
|
|
//
|
|
// width=2 is in the tab character. In this case, IndentPosition returns
|
|
// (pos=1, padding=2)
|
|
func IndentPosition(bs []byte, currentPos, width int) (pos, padding int) {
|
|
if width == 0 {
|
|
return 0, 0
|
|
}
|
|
w := 0
|
|
l := len(bs)
|
|
i := 0
|
|
hasTab := false
|
|
for ; i < l; i++ {
|
|
if bs[i] == '\t' {
|
|
w += TabWidth(currentPos + w)
|
|
hasTab = true
|
|
} else if bs[i] == ' ' {
|
|
w++
|
|
} else {
|
|
break
|
|
}
|
|
}
|
|
if w >= width {
|
|
if !hasTab {
|
|
return width, 0
|
|
}
|
|
return i, w - width
|
|
}
|
|
return -1, -1
|
|
}
|
|
|
|
// IndentPositionPadding searches an indent position with the given width for the given line.
|
|
// This function is mostly same as IndentPosition except this function
|
|
// takes account into additional paddings.
|
|
func IndentPositionPadding(bs []byte, currentPos, paddingv, width int) (pos, padding int) {
|
|
if width == 0 {
|
|
return 0, paddingv
|
|
}
|
|
w := 0
|
|
i := 0
|
|
l := len(bs)
|
|
for ; i < l; i++ {
|
|
if bs[i] == '\t' {
|
|
w += TabWidth(currentPos + w)
|
|
} else if bs[i] == ' ' {
|
|
w++
|
|
} else {
|
|
break
|
|
}
|
|
}
|
|
if w >= width {
|
|
return i - paddingv, w - width
|
|
}
|
|
return -1, -1
|
|
}
|
|
|
|
// DedentPosition dedents lines by the given width.
|
|
func DedentPosition(bs []byte, currentPos, width int) (pos, padding int) {
|
|
if width == 0 {
|
|
return 0, 0
|
|
}
|
|
w := 0
|
|
l := len(bs)
|
|
i := 0
|
|
for ; i < l; i++ {
|
|
if bs[i] == '\t' {
|
|
w += TabWidth(currentPos + w)
|
|
} else if bs[i] == ' ' {
|
|
w++
|
|
} else {
|
|
break
|
|
}
|
|
}
|
|
if w >= width {
|
|
return i, w - width
|
|
}
|
|
return i, 0
|
|
}
|
|
|
|
// DedentPositionPadding dedents lines by the given width.
|
|
// This function is mostly same as DedentPosition except this function
|
|
// takes account into additional paddings.
|
|
func DedentPositionPadding(bs []byte, currentPos, paddingv, width int) (pos, padding int) {
|
|
if width == 0 {
|
|
return 0, paddingv
|
|
}
|
|
|
|
w := 0
|
|
i := 0
|
|
l := len(bs)
|
|
for ; i < l; i++ {
|
|
if bs[i] == '\t' {
|
|
w += TabWidth(currentPos + w)
|
|
} else if bs[i] == ' ' {
|
|
w++
|
|
} else {
|
|
break
|
|
}
|
|
}
|
|
if w >= width {
|
|
return i - paddingv, w - width
|
|
}
|
|
return i - paddingv, 0
|
|
}
|
|
|
|
// IndentWidth calculate an indent width for the given line.
|
|
func IndentWidth(bs []byte, currentPos int) (width, pos int) {
|
|
l := len(bs)
|
|
for i := 0; i < l; i++ {
|
|
b := bs[i]
|
|
if b == ' ' {
|
|
width++
|
|
pos++
|
|
} else if b == '\t' {
|
|
width += TabWidth(currentPos + width)
|
|
pos++
|
|
} else {
|
|
break
|
|
}
|
|
}
|
|
return
|
|
}
|
|
|
|
// FirstNonSpacePosition returns a potisoin line that is a first nonspace
|
|
// character.
|
|
func FirstNonSpacePosition(bs []byte) int {
|
|
i := 0
|
|
for ; i < len(bs); i++ {
|
|
c := bs[i]
|
|
if c == ' ' || c == '\t' {
|
|
continue
|
|
}
|
|
if c == '\n' {
|
|
return -1
|
|
}
|
|
return i
|
|
}
|
|
return -1
|
|
}
|
|
|
|
// FindClosure returns a position that closes the given opener.
|
|
// If codeSpan is set true, it ignores characters in code spans.
|
|
// If allowNesting is set true, closures correspond to nested opener will be
|
|
// ignored.
|
|
func FindClosure(bs []byte, opener, closure byte, codeSpan, allowNesting bool) int {
|
|
i := 0
|
|
opened := 1
|
|
codeSpanOpener := 0
|
|
for i < len(bs) {
|
|
c := bs[i]
|
|
if codeSpan && codeSpanOpener != 0 && c == '`' {
|
|
codeSpanCloser := 0
|
|
for ; i < len(bs); i++ {
|
|
if bs[i] == '`' {
|
|
codeSpanCloser++
|
|
} else {
|
|
i--
|
|
break
|
|
}
|
|
}
|
|
if codeSpanCloser == codeSpanOpener {
|
|
codeSpanOpener = 0
|
|
}
|
|
} else if c == '\\' && i < len(bs)-1 && IsPunct(bs[i+1]) {
|
|
i += 2
|
|
continue
|
|
} else if codeSpan && codeSpanOpener == 0 && c == '`' {
|
|
for ; i < len(bs); i++ {
|
|
if bs[i] == '`' {
|
|
codeSpanOpener++
|
|
} else {
|
|
i--
|
|
break
|
|
}
|
|
}
|
|
} else if (codeSpan && codeSpanOpener == 0) || !codeSpan {
|
|
if c == closure {
|
|
opened--
|
|
if opened == 0 {
|
|
return i
|
|
}
|
|
} else if c == opener {
|
|
if !allowNesting {
|
|
return -1
|
|
}
|
|
opened++
|
|
}
|
|
}
|
|
i++
|
|
}
|
|
return -1
|
|
}
|
|
|
|
// TrimLeft trims characters in the given s from head of the source.
|
|
// bytes.TrimLeft offers same functionalities, but bytes.TrimLeft
|
|
// allocates new buffer for the result.
|
|
func TrimLeft(source, b []byte) []byte {
|
|
i := 0
|
|
for ; i < len(source); i++ {
|
|
c := source[i]
|
|
found := false
|
|
for j := 0; j < len(b); j++ {
|
|
if c == b[j] {
|
|
found = true
|
|
break
|
|
}
|
|
}
|
|
if !found {
|
|
break
|
|
}
|
|
}
|
|
return source[i:]
|
|
}
|
|
|
|
// TrimRight trims characters in the given s from tail of the source.
|
|
func TrimRight(source, b []byte) []byte {
|
|
i := len(source) - 1
|
|
for ; i >= 0; i-- {
|
|
c := source[i]
|
|
found := false
|
|
for j := 0; j < len(b); j++ {
|
|
if c == b[j] {
|
|
found = true
|
|
break
|
|
}
|
|
}
|
|
if !found {
|
|
break
|
|
}
|
|
}
|
|
return source[:i+1]
|
|
}
|
|
|
|
// TrimLeftLength returns a length of leading specified characters.
|
|
func TrimLeftLength(source, s []byte) int {
|
|
return len(source) - len(TrimLeft(source, s))
|
|
}
|
|
|
|
// TrimRightLength returns a length of trailing specified characters.
|
|
func TrimRightLength(source, s []byte) int {
|
|
return len(source) - len(TrimRight(source, s))
|
|
}
|
|
|
|
// TrimLeftSpaceLength returns a length of leading space characters.
|
|
func TrimLeftSpaceLength(source []byte) int {
|
|
i := 0
|
|
for ; i < len(source); i++ {
|
|
if !IsSpace(source[i]) {
|
|
break
|
|
}
|
|
}
|
|
return i
|
|
}
|
|
|
|
// TrimRightSpaceLength returns a length of trailing space characters.
|
|
func TrimRightSpaceLength(source []byte) int {
|
|
l := len(source)
|
|
i := l - 1
|
|
for ; i >= 0; i-- {
|
|
if !IsSpace(source[i]) {
|
|
break
|
|
}
|
|
}
|
|
if i < 0 {
|
|
return l
|
|
}
|
|
return l - 1 - i
|
|
}
|
|
|
|
// TrimLeftSpace returns a subslice of the given string by slicing off all leading
|
|
// space characters.
|
|
func TrimLeftSpace(source []byte) []byte {
|
|
return TrimLeft(source, spaces)
|
|
}
|
|
|
|
// TrimRightSpace returns a subslice of the given string by slicing off all trailing
|
|
// space characters.
|
|
func TrimRightSpace(source []byte) []byte {
|
|
return TrimRight(source, spaces)
|
|
}
|
|
|
|
// ReplaceSpaces replaces sequence of spaces with the given repl.
|
|
func ReplaceSpaces(source []byte, repl byte) []byte {
|
|
var ret []byte
|
|
start := -1
|
|
for i, c := range source {
|
|
iss := IsSpace(c)
|
|
if start < 0 && iss {
|
|
start = i
|
|
continue
|
|
} else if start >= 0 && iss {
|
|
continue
|
|
} else if start >= 0 {
|
|
if ret == nil {
|
|
ret = make([]byte, 0, len(source))
|
|
ret = append(ret, source[:start]...)
|
|
}
|
|
ret = append(ret, repl)
|
|
start = -1
|
|
}
|
|
if ret != nil {
|
|
ret = append(ret, c)
|
|
}
|
|
}
|
|
if start >= 0 && ret != nil {
|
|
ret = append(ret, repl)
|
|
}
|
|
if ret == nil {
|
|
return source
|
|
}
|
|
return ret
|
|
}
|
|
|
|
// ToRune decode given bytes start at pos and returns a rune.
|
|
func ToRune(source []byte, pos int) rune {
|
|
i := pos
|
|
for ; i >= 0; i-- {
|
|
if utf8.RuneStart(source[i]) {
|
|
break
|
|
}
|
|
}
|
|
r, _ := utf8.DecodeRune(source[i:])
|
|
return r
|
|
}
|
|
|
|
// ToValidRune returns 0xFFFD if the given rune is invalid, otherwise v.
|
|
func ToValidRune(v rune) rune {
|
|
if v == 0 || !utf8.ValidRune(v) {
|
|
return rune(0xFFFD)
|
|
}
|
|
return v
|
|
}
|
|
|
|
// ToLinkReference convert given bytes into a valid link reference string.
|
|
// ToLinkReference trims leading and trailing spaces and convert into lower
|
|
// case and replace spaces with a single space character.
|
|
func ToLinkReference(v []byte) string {
|
|
v = TrimLeftSpace(v)
|
|
v = TrimRightSpace(v)
|
|
return strings.ToLower(string(ReplaceSpaces(v, ' ')))
|
|
}
|
|
|
|
var htmlEscapeTable = [256][]byte{nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, []byte("""), nil, nil, nil, []byte("&"), nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, []byte("<"), nil, []byte(">"), nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil}
|
|
|
|
// EscapeHTMLByte returns HTML escaped bytes if the given byte should be escaped,
|
|
// otherwise nil.
|
|
func EscapeHTMLByte(b byte) []byte {
|
|
return htmlEscapeTable[b]
|
|
}
|
|
|
|
// EscapeHTML escapes characters that should be escaped in HTML text.
|
|
func EscapeHTML(v []byte) []byte {
|
|
cob := NewCopyOnWriteBuffer(v)
|
|
n := 0
|
|
for i := 0; i < len(v); i++ {
|
|
c := v[i]
|
|
escaped := htmlEscapeTable[c]
|
|
if escaped != nil {
|
|
cob.Write(v[n:i])
|
|
cob.Write(escaped)
|
|
n = i + 1
|
|
}
|
|
}
|
|
if cob.IsCopied() {
|
|
cob.Write(v[n:])
|
|
}
|
|
return cob.Bytes()
|
|
}
|
|
|
|
// UnescapePunctuations unescapes blackslash escaped punctuations.
|
|
func UnescapePunctuations(source []byte) []byte {
|
|
cob := NewCopyOnWriteBuffer(source)
|
|
limit := len(source)
|
|
n := 0
|
|
for i := 0; i < limit; {
|
|
c := source[i]
|
|
if i < limit-1 && c == '\\' && IsPunct(source[i+1]) {
|
|
cob.Write(source[n:i])
|
|
cob.WriteByte(source[i+1])
|
|
i += 2
|
|
n = i
|
|
continue
|
|
}
|
|
i++
|
|
}
|
|
if cob.IsCopied() {
|
|
cob.Write(source[n:])
|
|
}
|
|
return cob.Bytes()
|
|
}
|
|
|
|
// ResolveNumericReferences resolve numeric references like 'Ӓ" .
|
|
func ResolveNumericReferences(source []byte) []byte {
|
|
cob := NewCopyOnWriteBuffer(source)
|
|
buf := make([]byte, 6, 6)
|
|
limit := len(source)
|
|
ok := false
|
|
n := 0
|
|
for i := 0; i < limit; i++ {
|
|
if source[i] == '&' {
|
|
pos := i
|
|
next := i + 1
|
|
if next < limit && source[next] == '#' {
|
|
nnext := next + 1
|
|
if nnext < limit {
|
|
nc := source[nnext]
|
|
// code point like #x22;
|
|
if nnext < limit && nc == 'x' || nc == 'X' {
|
|
start := nnext + 1
|
|
i, ok = ReadWhile(source, [2]int{start, limit}, IsHexDecimal)
|
|
if ok && i < limit && source[i] == ';' {
|
|
v, _ := strconv.ParseUint(BytesToReadOnlyString(source[start:i]), 16, 32)
|
|
cob.Write(source[n:pos])
|
|
n = i + 1
|
|
runeSize := utf8.EncodeRune(buf, ToValidRune(rune(v)))
|
|
cob.Write(buf[:runeSize])
|
|
continue
|
|
}
|
|
// code point like #1234;
|
|
} else if nc >= '0' && nc <= '9' {
|
|
start := nnext
|
|
i, ok = ReadWhile(source, [2]int{start, limit}, IsNumeric)
|
|
if ok && i < limit && i-start < 8 && source[i] == ';' {
|
|
v, _ := strconv.ParseUint(BytesToReadOnlyString(source[start:i]), 0, 32)
|
|
cob.Write(source[n:pos])
|
|
n = i + 1
|
|
runeSize := utf8.EncodeRune(buf, ToValidRune(rune(v)))
|
|
cob.Write(buf[:runeSize])
|
|
continue
|
|
}
|
|
}
|
|
}
|
|
}
|
|
i = next - 1
|
|
}
|
|
}
|
|
if cob.IsCopied() {
|
|
cob.Write(source[n:])
|
|
}
|
|
return cob.Bytes()
|
|
}
|
|
|
|
// ResolveEntityNames resolve entity references like 'ö" .
|
|
func ResolveEntityNames(source []byte) []byte {
|
|
cob := NewCopyOnWriteBuffer(source)
|
|
limit := len(source)
|
|
ok := false
|
|
n := 0
|
|
for i := 0; i < limit; i++ {
|
|
if source[i] == '&' {
|
|
pos := i
|
|
next := i + 1
|
|
if !(next < limit && source[next] == '#') {
|
|
start := next
|
|
i, ok = ReadWhile(source, [2]int{start, limit}, IsAlphaNumeric)
|
|
if ok && i < limit && source[i] == ';' {
|
|
name := BytesToReadOnlyString(source[start:i])
|
|
entity, ok := LookUpHTML5EntityByName(name)
|
|
if ok {
|
|
cob.Write(source[n:pos])
|
|
n = i + 1
|
|
cob.Write(entity.Characters)
|
|
continue
|
|
}
|
|
}
|
|
}
|
|
i = next - 1
|
|
}
|
|
}
|
|
if cob.IsCopied() {
|
|
cob.Write(source[n:])
|
|
}
|
|
return cob.Bytes()
|
|
}
|
|
|
|
var htmlSpace = []byte("%20")
|
|
|
|
// URLEscape escape the given URL.
|
|
// If resolveReference is set true:
|
|
// 1. unescape punctuations
|
|
// 2. resolve numeric references
|
|
// 3. resolve entity references
|
|
//
|
|
// URL encoded values (%xx) are keeped as is.
|
|
func URLEscape(v []byte, resolveReference bool) []byte {
|
|
if resolveReference {
|
|
v = UnescapePunctuations(v)
|
|
v = ResolveNumericReferences(v)
|
|
v = ResolveEntityNames(v)
|
|
}
|
|
cob := NewCopyOnWriteBuffer(v)
|
|
limit := len(v)
|
|
n := 0
|
|
|
|
for i := 0; i < limit; {
|
|
c := v[i]
|
|
if urlEscapeTable[c] == 1 {
|
|
i++
|
|
continue
|
|
}
|
|
if c == '%' && i+2 < limit && IsHexDecimal(v[i+1]) && IsHexDecimal(v[i+1]) {
|
|
i += 3
|
|
continue
|
|
}
|
|
u8len := utf8lenTable[c]
|
|
if u8len == 99 { // invalid utf8 leading byte, skip it
|
|
i++
|
|
continue
|
|
}
|
|
if c == ' ' {
|
|
cob.Write(v[n:i])
|
|
cob.Write(htmlSpace)
|
|
i++
|
|
n = i
|
|
continue
|
|
}
|
|
if int(u8len) >= len(v) {
|
|
u8len = int8(len(v) - 1)
|
|
}
|
|
if u8len == 0 {
|
|
i++
|
|
n = i
|
|
continue
|
|
}
|
|
cob.Write(v[n:i])
|
|
stop := i + int(u8len)
|
|
if stop > len(v) {
|
|
i++
|
|
n = i
|
|
continue
|
|
}
|
|
cob.Write(StringToReadOnlyBytes(url.QueryEscape(string(v[i:stop]))))
|
|
i += int(u8len)
|
|
n = i
|
|
}
|
|
if cob.IsCopied() && n < limit {
|
|
cob.Write(v[n:])
|
|
}
|
|
return cob.Bytes()
|
|
}
|
|
|
|
// FindURLIndex returns a stop index value if the given bytes seem an URL.
|
|
// This function is equivalent to [A-Za-z][A-Za-z0-9.+-]{1,31}:[^<>\x00-\x20]* .
|
|
func FindURLIndex(b []byte) int {
|
|
i := 0
|
|
if !(len(b) > 0 && urlTable[b[i]]&7 == 7) {
|
|
return -1
|
|
}
|
|
i++
|
|
for ; i < len(b); i++ {
|
|
c := b[i]
|
|
if urlTable[c]&4 != 4 {
|
|
break
|
|
}
|
|
}
|
|
if i == 1 || i > 33 || i >= len(b) {
|
|
return -1
|
|
}
|
|
if b[i] != ':' {
|
|
return -1
|
|
}
|
|
i++
|
|
for ; i < len(b); i++ {
|
|
c := b[i]
|
|
if urlTable[c]&1 != 1 {
|
|
break
|
|
}
|
|
}
|
|
return i
|
|
}
|
|
|
|
var emailDomainRegexp = regexp.MustCompile(`^[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*`)
|
|
|
|
// FindEmailIndex returns a stop index value if the given bytes seem an email address.
|
|
func FindEmailIndex(b []byte) int {
|
|
// TODO: eliminate regexps
|
|
i := 0
|
|
for ; i < len(b); i++ {
|
|
c := b[i]
|
|
if emailTable[c]&1 != 1 {
|
|
break
|
|
}
|
|
}
|
|
if i == 0 {
|
|
return -1
|
|
}
|
|
if i >= len(b) || b[i] != '@' {
|
|
return -1
|
|
}
|
|
i++
|
|
if i >= len(b) {
|
|
return -1
|
|
}
|
|
match := emailDomainRegexp.FindSubmatchIndex(b[i:])
|
|
if match == nil {
|
|
return -1
|
|
}
|
|
return i + match[1]
|
|
}
|
|
|
|
var spaces = []byte(" \t\n\x0b\x0c\x0d")
|
|
|
|
var spaceTable = [256]int8{0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
|
|
|
|
var punctTable = [256]int8{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
|
|
|
|
// a-zA-Z0-9, ;/?:@&=+$,-_.!~*'()#
|
|
var urlEscapeTable = [256]int8{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
|
|
|
|
var utf8lenTable = [256]int8{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 99, 99, 99, 99, 99, 99, 99, 99}
|
|
|
|
var urlTable = [256]uint8{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 5, 1, 5, 5, 1, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 1, 1, 0, 1, 0, 1, 1, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 1, 1, 1, 1, 1, 1, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}
|
|
|
|
var emailTable = [256]uint8{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
|
|
|
|
// UTF8Len returns a byte length of the utf-8 character.
|
|
func UTF8Len(b byte) int8 {
|
|
return utf8lenTable[b]
|
|
}
|
|
|
|
// IsPunct returns true if the given character is a punctuation, otherwise false.
|
|
func IsPunct(c byte) bool {
|
|
return punctTable[c] == 1
|
|
}
|
|
|
|
// IsSpace returns true if the given character is a space, otherwise false.
|
|
func IsSpace(c byte) bool {
|
|
return spaceTable[c] == 1
|
|
}
|
|
|
|
// IsNumeric returns true if the given character is a numeric, otherwise false.
|
|
func IsNumeric(c byte) bool {
|
|
return c >= '0' && c <= '9'
|
|
}
|
|
|
|
// IsHexDecimal returns true if the given character is a hexdecimal, otherwise false.
|
|
func IsHexDecimal(c byte) bool {
|
|
return c >= '0' && c <= '9' || c >= 'a' && c <= 'f' || c >= 'A' && c <= 'F'
|
|
}
|
|
|
|
// IsAlphaNumeric returns true if the given character is a alphabet or a numeric, otherwise false.
|
|
func IsAlphaNumeric(c byte) bool {
|
|
return c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c >= '0' && c <= '9'
|
|
}
|
|
|
|
// A BufWriter is a subset of the bufio.Writer .
|
|
type BufWriter interface {
|
|
io.Writer
|
|
Available() int
|
|
Buffered() int
|
|
Flush() error
|
|
WriteByte(c byte) error
|
|
WriteRune(r rune) (size int, err error)
|
|
WriteString(s string) (int, error)
|
|
}
|
|
|
|
// A PrioritizedValue struct holds pair of an arbitrary value and a priority.
|
|
type PrioritizedValue struct {
|
|
// Value is an arbitrary value that you want to prioritize.
|
|
Value interface{}
|
|
// Priority is a priority of the value.
|
|
Priority int
|
|
}
|
|
|
|
// PrioritizedSlice is a slice of the PrioritizedValues
|
|
type PrioritizedSlice []PrioritizedValue
|
|
|
|
// Sort sorts the PrioritizedSlice in ascending order.
|
|
func (s PrioritizedSlice) Sort() {
|
|
sort.Slice(s, func(i, j int) bool {
|
|
return s[i].Priority < s[j].Priority
|
|
})
|
|
}
|
|
|
|
// Remove removes the given value from this slice.
|
|
func (s PrioritizedSlice) Remove(v interface{}) PrioritizedSlice {
|
|
i := 0
|
|
found := false
|
|
for ; i < len(s); i++ {
|
|
if s[i].Value == v {
|
|
found = true
|
|
break
|
|
}
|
|
}
|
|
if !found {
|
|
return s
|
|
}
|
|
return append(s[:i], s[i+1:]...)
|
|
}
|
|
|
|
// Prioritized returns a new PrioritizedValue.
|
|
func Prioritized(v interface{}, priority int) PrioritizedValue {
|
|
return PrioritizedValue{v, priority}
|
|
}
|
|
|
|
func bytesHash(b []byte) uint64 {
|
|
var hash uint64 = 5381
|
|
for _, c := range b {
|
|
hash = ((hash << 5) + hash) + uint64(c)
|
|
}
|
|
return hash
|
|
}
|
|
|
|
// BytesFilter is a efficient data structure for checking whether bytes exist or not.
|
|
// BytesFilter is thread-safe.
|
|
type BytesFilter interface {
|
|
// Add adds given bytes to this set.
|
|
Add([]byte)
|
|
|
|
// Contains return true if this set contains given bytes, otherwise false.
|
|
Contains([]byte) bool
|
|
|
|
// Extend copies this filter and adds given bytes to new filter.
|
|
Extend(...[]byte) BytesFilter
|
|
}
|
|
|
|
type bytesFilter struct {
|
|
chars [256]uint8
|
|
threshold int
|
|
slots [][][]byte
|
|
}
|
|
|
|
// NewBytesFilter returns a new BytesFilter.
|
|
func NewBytesFilter(elements ...[]byte) BytesFilter {
|
|
s := &bytesFilter{
|
|
threshold: 3,
|
|
slots: make([][][]byte, 64),
|
|
}
|
|
for _, element := range elements {
|
|
s.Add(element)
|
|
}
|
|
return s
|
|
}
|
|
|
|
func (s *bytesFilter) Add(b []byte) {
|
|
l := len(b)
|
|
m := s.threshold
|
|
if l < s.threshold {
|
|
m = l
|
|
}
|
|
for i := 0; i < m; i++ {
|
|
s.chars[b[i]] |= 1 << uint8(i)
|
|
}
|
|
h := bytesHash(b) % uint64(len(s.slots))
|
|
slot := s.slots[h]
|
|
if slot == nil {
|
|
slot = [][]byte{}
|
|
}
|
|
s.slots[h] = append(slot, b)
|
|
}
|
|
|
|
func (s *bytesFilter) Extend(bs ...[]byte) BytesFilter {
|
|
newFilter := NewBytesFilter().(*bytesFilter)
|
|
newFilter.chars = s.chars
|
|
newFilter.threshold = s.threshold
|
|
for k, v := range s.slots {
|
|
newSlot := make([][]byte, len(v))
|
|
copy(newSlot, v)
|
|
newFilter.slots[k] = v
|
|
}
|
|
for _, b := range bs {
|
|
newFilter.Add(b)
|
|
}
|
|
return newFilter
|
|
}
|
|
|
|
func (s *bytesFilter) Contains(b []byte) bool {
|
|
l := len(b)
|
|
m := s.threshold
|
|
if l < s.threshold {
|
|
m = l
|
|
}
|
|
for i := 0; i < m; i++ {
|
|
if (s.chars[b[i]] & (1 << uint8(i))) == 0 {
|
|
return false
|
|
}
|
|
}
|
|
h := bytesHash(b) % uint64(len(s.slots))
|
|
slot := s.slots[h]
|
|
if slot == nil || len(slot) == 0 {
|
|
return false
|
|
}
|
|
for _, element := range slot {
|
|
if bytes.Equal(element, b) {
|
|
return true
|
|
}
|
|
}
|
|
return false
|
|
}
|