mirror of
https://github.com/golang/go
synced 2024-11-12 08:10:21 -07:00
html: move the HTML parser to an exp/html package. The parser is a
work in progress, and we are not ready to freeze its API for Go 1. Package html still exists, containing just two functions: EscapeString and UnescapeString. Both the packages at exp/html and html are "package html". The former is a superset of the latter. At some point in the future, the exp/html code will move back into html, once we have finalized the parser API. R=rsc, dsymonds CC=golang-dev https://golang.org/cl/5571059
This commit is contained in:
parent
66599c4070
commit
324513bc5f
@ -82,6 +82,7 @@ DIRS=\
|
||||
exp/ebnf\
|
||||
exp/ebnflint\
|
||||
exp/gotype\
|
||||
exp/html\
|
||||
exp/norm\
|
||||
exp/spdy\
|
||||
exp/ssh\
|
||||
|
20
src/pkg/exp/html/Makefile
Normal file
20
src/pkg/exp/html/Makefile
Normal file
@ -0,0 +1,20 @@
|
||||
# Copyright 2010 The Go Authors. All rights reserved.
|
||||
# Use of this source code is governed by a BSD-style
|
||||
# license that can be found in the LICENSE file.
|
||||
|
||||
include ../../../Make.inc
|
||||
|
||||
TARG=html
|
||||
GOFILES=\
|
||||
const.go\
|
||||
doc.go\
|
||||
doctype.go\
|
||||
entity.go\
|
||||
escape.go\
|
||||
foreign.go\
|
||||
node.go\
|
||||
parse.go\
|
||||
render.go\
|
||||
token.go\
|
||||
|
||||
include ../../../Make.pkg
|
2253
src/pkg/exp/html/entity.go
Normal file
2253
src/pkg/exp/html/entity.go
Normal file
File diff suppressed because it is too large
Load Diff
29
src/pkg/exp/html/entity_test.go
Normal file
29
src/pkg/exp/html/entity_test.go
Normal file
@ -0,0 +1,29 @@
|
||||
// Copyright 2010 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package html
|
||||
|
||||
import (
|
||||
"testing"
|
||||
"unicode/utf8"
|
||||
)
|
||||
|
||||
func TestEntityLength(t *testing.T) {
|
||||
// We verify that the length of UTF-8 encoding of each value is <= 1 + len(key).
|
||||
// The +1 comes from the leading "&". This property implies that the length of
|
||||
// unescaped text is <= the length of escaped text.
|
||||
for k, v := range entity {
|
||||
if 1+len(k) < utf8.RuneLen(v) {
|
||||
t.Error("escaped entity &" + k + " is shorter than its UTF-8 encoding " + string(v))
|
||||
}
|
||||
if len(k) > longestEntityWithoutSemicolon && k[len(k)-1] != ';' {
|
||||
t.Errorf("entity name %s is %d characters, but longestEntityWithoutSemicolon=%d", k, len(k), longestEntityWithoutSemicolon)
|
||||
}
|
||||
}
|
||||
for k, v := range entity2 {
|
||||
if 1+len(k) < utf8.RuneLen(v[0])+utf8.RuneLen(v[1]) {
|
||||
t.Error("escaped entity &" + k + " is shorter than its UTF-8 encoding " + string(v[0]) + string(v[1]))
|
||||
}
|
||||
}
|
||||
}
|
253
src/pkg/exp/html/escape.go
Normal file
253
src/pkg/exp/html/escape.go
Normal file
@ -0,0 +1,253 @@
|
||||
// Copyright 2010 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package html
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"strings"
|
||||
"unicode/utf8"
|
||||
)
|
||||
|
||||
// These replacements permit compatibility with old numeric entities that
|
||||
// assumed Windows-1252 encoding.
|
||||
// http://www.whatwg.org/specs/web-apps/current-work/multipage/tokenization.html#consume-a-character-reference
|
||||
var replacementTable = [...]rune{
|
||||
'\u20AC', // First entry is what 0x80 should be replaced with.
|
||||
'\u0081',
|
||||
'\u201A',
|
||||
'\u0192',
|
||||
'\u201E',
|
||||
'\u2026',
|
||||
'\u2020',
|
||||
'\u2021',
|
||||
'\u02C6',
|
||||
'\u2030',
|
||||
'\u0160',
|
||||
'\u2039',
|
||||
'\u0152',
|
||||
'\u008D',
|
||||
'\u017D',
|
||||
'\u008F',
|
||||
'\u0090',
|
||||
'\u2018',
|
||||
'\u2019',
|
||||
'\u201C',
|
||||
'\u201D',
|
||||
'\u2022',
|
||||
'\u2013',
|
||||
'\u2014',
|
||||
'\u02DC',
|
||||
'\u2122',
|
||||
'\u0161',
|
||||
'\u203A',
|
||||
'\u0153',
|
||||
'\u009D',
|
||||
'\u017E',
|
||||
'\u0178', // Last entry is 0x9F.
|
||||
// 0x00->'\uFFFD' is handled programmatically.
|
||||
// 0x0D->'\u000D' is a no-op.
|
||||
}
|
||||
|
||||
// unescapeEntity reads an entity like "<" from b[src:] and writes the
|
||||
// corresponding "<" to b[dst:], returning the incremented dst and src cursors.
|
||||
// Precondition: b[src] == '&' && dst <= src.
|
||||
// attribute should be true if parsing an attribute value.
|
||||
func unescapeEntity(b []byte, dst, src int, attribute bool) (dst1, src1 int) {
|
||||
// http://www.whatwg.org/specs/web-apps/current-work/multipage/tokenization.html#consume-a-character-reference
|
||||
|
||||
// i starts at 1 because we already know that s[0] == '&'.
|
||||
i, s := 1, b[src:]
|
||||
|
||||
if len(s) <= 1 {
|
||||
b[dst] = b[src]
|
||||
return dst + 1, src + 1
|
||||
}
|
||||
|
||||
if s[i] == '#' {
|
||||
if len(s) <= 3 { // We need to have at least "&#.".
|
||||
b[dst] = b[src]
|
||||
return dst + 1, src + 1
|
||||
}
|
||||
i++
|
||||
c := s[i]
|
||||
hex := false
|
||||
if c == 'x' || c == 'X' {
|
||||
hex = true
|
||||
i++
|
||||
}
|
||||
|
||||
x := '\x00'
|
||||
for i < len(s) {
|
||||
c = s[i]
|
||||
i++
|
||||
if hex {
|
||||
if '0' <= c && c <= '9' {
|
||||
x = 16*x + rune(c) - '0'
|
||||
continue
|
||||
} else if 'a' <= c && c <= 'f' {
|
||||
x = 16*x + rune(c) - 'a' + 10
|
||||
continue
|
||||
} else if 'A' <= c && c <= 'F' {
|
||||
x = 16*x + rune(c) - 'A' + 10
|
||||
continue
|
||||
}
|
||||
} else if '0' <= c && c <= '9' {
|
||||
x = 10*x + rune(c) - '0'
|
||||
continue
|
||||
}
|
||||
if c != ';' {
|
||||
i--
|
||||
}
|
||||
break
|
||||
}
|
||||
|
||||
if i <= 3 { // No characters matched.
|
||||
b[dst] = b[src]
|
||||
return dst + 1, src + 1
|
||||
}
|
||||
|
||||
if 0x80 <= x && x <= 0x9F {
|
||||
// Replace characters from Windows-1252 with UTF-8 equivalents.
|
||||
x = replacementTable[x-0x80]
|
||||
} else if x == 0 || (0xD800 <= x && x <= 0xDFFF) || x > 0x10FFFF {
|
||||
// Replace invalid characters with the replacement character.
|
||||
x = '\uFFFD'
|
||||
}
|
||||
|
||||
return dst + utf8.EncodeRune(b[dst:], x), src + i
|
||||
}
|
||||
|
||||
// Consume the maximum number of characters possible, with the
|
||||
// consumed characters matching one of the named references.
|
||||
|
||||
for i < len(s) {
|
||||
c := s[i]
|
||||
i++
|
||||
// Lower-cased characters are more common in entities, so we check for them first.
|
||||
if 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z' || '0' <= c && c <= '9' {
|
||||
continue
|
||||
}
|
||||
if c != ';' {
|
||||
i--
|
||||
}
|
||||
break
|
||||
}
|
||||
|
||||
entityName := string(s[1:i])
|
||||
if entityName == "" {
|
||||
// No-op.
|
||||
} else if attribute && entityName[len(entityName)-1] != ';' && len(s) > i && s[i] == '=' {
|
||||
// No-op.
|
||||
} else if x := entity[entityName]; x != 0 {
|
||||
return dst + utf8.EncodeRune(b[dst:], x), src + i
|
||||
} else if x := entity2[entityName]; x[0] != 0 {
|
||||
dst1 := dst + utf8.EncodeRune(b[dst:], x[0])
|
||||
return dst1 + utf8.EncodeRune(b[dst1:], x[1]), src + i
|
||||
} else if !attribute {
|
||||
maxLen := len(entityName) - 1
|
||||
if maxLen > longestEntityWithoutSemicolon {
|
||||
maxLen = longestEntityWithoutSemicolon
|
||||
}
|
||||
for j := maxLen; j > 1; j-- {
|
||||
if x := entity[entityName[:j]]; x != 0 {
|
||||
return dst + utf8.EncodeRune(b[dst:], x), src + j + 1
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
dst1, src1 = dst+i, src+i
|
||||
copy(b[dst:dst1], b[src:src1])
|
||||
return dst1, src1
|
||||
}
|
||||
|
||||
// unescape unescapes b's entities in-place, so that "a<b" becomes "a<b".
|
||||
func unescape(b []byte) []byte {
|
||||
for i, c := range b {
|
||||
if c == '&' {
|
||||
dst, src := unescapeEntity(b, i, i, false)
|
||||
for src < len(b) {
|
||||
c := b[src]
|
||||
if c == '&' {
|
||||
dst, src = unescapeEntity(b, dst, src, false)
|
||||
} else {
|
||||
b[dst] = c
|
||||
dst, src = dst+1, src+1
|
||||
}
|
||||
}
|
||||
return b[0:dst]
|
||||
}
|
||||
}
|
||||
return b
|
||||
}
|
||||
|
||||
// lower lower-cases the A-Z bytes in b in-place, so that "aBc" becomes "abc".
|
||||
func lower(b []byte) []byte {
|
||||
for i, c := range b {
|
||||
if 'A' <= c && c <= 'Z' {
|
||||
b[i] = c + 'a' - 'A'
|
||||
}
|
||||
}
|
||||
return b
|
||||
}
|
||||
|
||||
const escapedChars = `&'<>"`
|
||||
|
||||
func escape(w writer, s string) error {
|
||||
i := strings.IndexAny(s, escapedChars)
|
||||
for i != -1 {
|
||||
if _, err := w.WriteString(s[:i]); err != nil {
|
||||
return err
|
||||
}
|
||||
var esc string
|
||||
switch s[i] {
|
||||
case '&':
|
||||
esc = "&"
|
||||
case '\'':
|
||||
esc = "'"
|
||||
case '<':
|
||||
esc = "<"
|
||||
case '>':
|
||||
esc = ">"
|
||||
case '"':
|
||||
esc = """
|
||||
default:
|
||||
panic("unrecognized escape character")
|
||||
}
|
||||
s = s[i+1:]
|
||||
if _, err := w.WriteString(esc); err != nil {
|
||||
return err
|
||||
}
|
||||
i = strings.IndexAny(s, escapedChars)
|
||||
}
|
||||
_, err := w.WriteString(s)
|
||||
return err
|
||||
}
|
||||
|
||||
// EscapeString escapes special characters like "<" to become "<". It
|
||||
// escapes only five such characters: amp, apos, lt, gt and quot.
|
||||
// UnescapeString(EscapeString(s)) == s always holds, but the converse isn't
|
||||
// always true.
|
||||
func EscapeString(s string) string {
|
||||
if strings.IndexAny(s, escapedChars) == -1 {
|
||||
return s
|
||||
}
|
||||
buf := bytes.NewBuffer(nil)
|
||||
escape(buf, s)
|
||||
return buf.String()
|
||||
}
|
||||
|
||||
// UnescapeString unescapes entities like "<" to become "<". It unescapes a
|
||||
// larger range of entities than EscapeString escapes. For example, "á"
|
||||
// unescapes to "á", as does "á" and "&xE1;".
|
||||
// UnescapeString(EscapeString(s)) == s always holds, but the converse isn't
|
||||
// always true.
|
||||
func UnescapeString(s string) string {
|
||||
for _, c := range s {
|
||||
if c == '&' {
|
||||
return string(unescape([]byte(s)))
|
||||
}
|
||||
}
|
||||
return s
|
||||
}
|
@ -6,15 +6,7 @@ include ../../Make.inc
|
||||
|
||||
TARG=html
|
||||
GOFILES=\
|
||||
const.go\
|
||||
doc.go\
|
||||
doctype.go\
|
||||
entity.go\
|
||||
escape.go\
|
||||
foreign.go\
|
||||
node.go\
|
||||
parse.go\
|
||||
render.go\
|
||||
token.go\
|
||||
|
||||
include ../../Make.pkg
|
||||
|
@ -10,6 +10,10 @@ import (
|
||||
"unicode/utf8"
|
||||
)
|
||||
|
||||
type writer interface {
|
||||
WriteString(string) (int, error)
|
||||
}
|
||||
|
||||
// These replacements permit compatibility with old numeric entities that
|
||||
// assumed Windows-1252 encoding.
|
||||
// http://www.whatwg.org/specs/web-apps/current-work/multipage/tokenization.html#consume-a-character-reference
|
||||
|
Loading…
Reference in New Issue
Block a user