1package blackfriday
 2
 3import (
 4	"html"
 5	"io"
 6)
 7
 8type escMap struct {
 9	char byte
10	seq  []byte
11}
12
13var htmlEscaper = []escMap{
14	{'&', []byte("&")},
15	{'<', []byte("&lt;")},
16	{'>', []byte("&gt;")},
17	{'"', []byte("&quot;")},
18}
19
20func escapeHTML(w io.Writer, s []byte) {
21	var start, end int
22	var sEnd byte
23	for end < len(s) {
24		sEnd = s[end]
25		if sEnd == '&' || sEnd == '<' || sEnd == '>' || sEnd == '"' {
26			for i := 0; i < len(htmlEscaper); i++ {
27				if sEnd == htmlEscaper[i].char {
28					w.Write(s[start:end])
29					w.Write(htmlEscaper[i].seq)
30					start = end + 1
31					break
32				}
33			}
34		}
35		end++
36	}
37	if start < len(s) && end <= len(s) {
38		w.Write(s[start:end])
39	}
40}
41
42func escLink(w io.Writer, text []byte) {
43	unesc := html.UnescapeString(string(text))
44	escapeHTML(w, []byte(unesc))
45}