dkforest

A forum and chat platform (onion)
git clone https://git.dasho.dev/n0tr1v/dkforest.git
Log | Files | Refs | LICENSE

esc.go (1367B)

      1 package blackfriday
      2 
      3 import (
      4 	"html"
      5 	"io"
      6 )
      7 
      8 var htmlEscaper = [256][]byte{
      9 	'&': []byte("&"),
     10 	'<': []byte("&lt;"),
     11 	'>': []byte("&gt;"),
     12 	'"': []byte("&quot;"),
     13 }
     14 
     15 func escapeHTML(w io.Writer, s []byte) {
     16 	escapeEntities(w, s, false)
     17 }
     18 
     19 func escapeAllHTML(w io.Writer, s []byte) {
     20 	escapeEntities(w, s, true)
     21 }
     22 
     23 func escapeEntities(w io.Writer, s []byte, escapeValidEntities bool) {
     24 	var start, end int
     25 	for end < len(s) {
     26 		escSeq := htmlEscaper[s[end]]
     27 		if escSeq != nil {
     28 			isEntity, entityEnd := nodeIsEntity(s, end)
     29 			if isEntity && !escapeValidEntities {
     30 				w.Write(s[start : entityEnd+1])
     31 				start = entityEnd + 1
     32 			} else {
     33 				w.Write(s[start:end])
     34 				w.Write(escSeq)
     35 				start = end + 1
     36 			}
     37 		}
     38 		end++
     39 	}
     40 	if start < len(s) && end <= len(s) {
     41 		w.Write(s[start:end])
     42 	}
     43 }
     44 
     45 func nodeIsEntity(s []byte, end int) (isEntity bool, endEntityPos int) {
     46 	isEntity = false
     47 	endEntityPos = end + 1
     48 
     49 	if s[end] == '&' {
     50 		for endEntityPos < len(s) {
     51 			if s[endEntityPos] == ';' {
     52 				if entities[string(s[end:endEntityPos+1])] {
     53 					isEntity = true
     54 					break
     55 				}
     56 			}
     57 			if !isalnum(s[endEntityPos]) && s[endEntityPos] != '&' && s[endEntityPos] != '#' {
     58 				break
     59 			}
     60 			endEntityPos++
     61 		}
     62 	}
     63 
     64 	return isEntity, endEntityPos
     65 }
     66 
     67 func escLink(w io.Writer, text []byte) {
     68 	unesc := html.UnescapeString(string(text))
     69 	escapeHTML(w, []byte(unesc))
     70 }