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// Copyright 2009 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 xml implements a simple XML 1.0 parser that
// understands XML name spaces.
package xml
// References:
// Annotated XML spec: http://www.xml.com/axml/testaxml.htm
// XML name spaces: http://www.w3.org/TR/REC-xml-names/
// TODO(rsc):
// Test error handling.
import (
"bufio"
"bytes"
"fmt"
"io"
"os"
"strconv"
"strings"
"unicode"
"utf8"
)
// A SyntaxError represents a syntax error in the XML input stream.
type SyntaxError struct {
Msg string
Line int
}
func (e *SyntaxError) String() string {
return "XML syntax error on line " + strconv.Itoa(e.Line) + ": " + e.Msg
}
// A Name represents an XML name (Local) annotated
// with a name space identifier (Space).
// In tokens returned by Parser.Token, the Space identifier
// is given as a canonical URL, not the short prefix used
// in the document being parsed.
type Name struct {
Space, Local string
}
// An Attr represents an attribute in an XML element (Name=Value).
type Attr struct {
Name Name
Value string
}
// A Token is an interface holding one of the token types:
// StartElement, EndElement, CharData, Comment, ProcInst, or Directive.
type Token interface{}
// A StartElement represents an XML start element.
type StartElement struct {
Name Name
Attr []Attr
}
func (e StartElement) Copy() StartElement {
attrs := make([]Attr, len(e.Attr))
copy(e.Attr, attrs)
e.Attr = attrs
return e
}
// An EndElement represents an XML end element.
type EndElement struct {
Name Name
}
// A CharData represents XML character data (raw text),
// in which XML escape sequences have been replaced by
// the characters they represent.
type CharData []byte
func makeCopy(b []byte) []byte {
b1 := make([]byte, len(b))
copy(b1, b)
return b1
}
func (c CharData) Copy() CharData { return CharData(makeCopy(c)) }
// A Comment represents an XML comment of the form <!--comment-->.
// The bytes do not include the <!-- and --> comment markers.
type Comment []byte
func (c Comment) Copy() Comment { return Comment(makeCopy(c)) }
// A ProcInst represents an XML processing instruction of the form <?target inst?>
type ProcInst struct {
Target string
Inst []byte
}
func (p ProcInst) Copy() ProcInst {
p.Inst = makeCopy(p.Inst)
return p
}
// A Directive represents an XML directive of the form <!text>.
// The bytes do not include the <! and > markers.
type Directive []byte
func (d Directive) Copy() Directive { return Directive(makeCopy(d)) }
// CopyToken returns a copy of a Token.
func CopyToken(t Token) Token {
switch v := t.(type) {
case CharData:
return v.Copy()
case Comment:
return v.Copy()
case Directive:
return v.Copy()
case ProcInst:
return v.Copy()
case StartElement:
return v.Copy()
}
return t
}
// A Parser represents an XML parser reading a particular input stream.
// The parser assumes that its input is encoded in UTF-8.
type Parser struct {
// Strict defaults to true, enforcing the requirements
// of the XML specification.
// If set to false, the parser allows input containing common
// mistakes:
// * If an element is missing an end tag, the parser invents
// end tags as necessary to keep the return values from Token
// properly balanced.
// * In attribute values and character data, unknown or malformed
// character entities (sequences beginning with &) are left alone.
//
// Setting:
//
// p.Strict = false;
// p.AutoClose = HTMLAutoClose;
// p.Entity = HTMLEntity
//
// creates a parser that can handle typical HTML.
Strict bool
// When Strict == false, AutoClose indicates a set of elements to
// consider closed immediately after they are opened, regardless
// of whether an end element is present.
AutoClose []string
// Entity can be used to map non-standard entity names to string replacements.
// The parser behaves as if these standard mappings are present in the map,
// regardless of the actual map content:
//
// "lt": "<",
// "gt": ">",
// "amp": "&",
// "apos": "'",
// "quot": `"`,
Entity map[string]string
// CharsetReader, if non-nil, defines a function to generate
// charset-conversion readers, converting from the provided
// non-UTF-8 charset into UTF-8. If CharsetReader is nil or
// returns an error, parsing stops with an error. One of the
// the CharsetReader's result values must be non-nil.
CharsetReader func(charset string, input io.Reader) (io.Reader, os.Error)
r io.ByteReader
buf bytes.Buffer
saved *bytes.Buffer
stk *stack
free *stack
needClose bool
toClose Name
nextToken Token
nextByte int
ns map[string]string
err os.Error
line int
tmp [32]byte
}
// NewParser creates a new XML parser reading from r.
func NewParser(r io.Reader) *Parser {
p := &Parser{
ns: make(map[string]string),
nextByte: -1,
line: 1,
Strict: true,
}
p.switchToReader(r)
return p
}
// Token returns the next XML token in the input stream.
// At the end of the input stream, Token returns nil, os.EOF.
//
// Slices of bytes in the returned token data refer to the
// parser's internal buffer and remain valid only until the next
// call to Token. To acquire a copy of the bytes, call CopyToken
// or the token's Copy method.
//
// Token expands self-closing elements such as <br/>
// into separate start and end elements returned by successive calls.
//
// Token guarantees that the StartElement and EndElement
// tokens it returns are properly nested and matched:
// if Token encounters an unexpected end element,
// it will return an error.
//
// Token implements XML name spaces as described by
// http://www.w3.org/TR/REC-xml-names/. Each of the
// Name structures contained in the Token has the Space
// set to the URL identifying its name space when known.
// If Token encounters an unrecognized name space prefix,
// it uses the prefix as the Space rather than report an error.
func (p *Parser) Token() (t Token, err os.Error) {
if p.nextToken != nil {
t = p.nextToken
p.nextToken = nil
} else if t, err = p.RawToken(); err != nil {
return
}
if !p.Strict {
if t1, ok := p.autoClose(t); ok {
p.nextToken = t
t = t1
}
}
switch t1 := t.(type) {
case StartElement:
// In XML name spaces, the translations listed in the
// attributes apply to the element name and
// to the other attribute names, so process
// the translations first.
for _, a := range t1.Attr {
if a.Name.Space == "xmlns" {
v, ok := p.ns[a.Name.Local]
p.pushNs(a.Name.Local, v, ok)
p.ns[a.Name.Local] = a.Value
}
if a.Name.Space == "" && a.Name.Local == "xmlns" {
// Default space for untagged names
v, ok := p.ns[""]
p.pushNs("", v, ok)
p.ns[""] = a.Value
}
}
p.translate(&t1.Name, true)
for i := range t1.Attr {
p.translate(&t1.Attr[i].Name, false)
}
p.pushElement(t1.Name)
t = t1
case EndElement:
p.translate(&t1.Name, true)
if !p.popElement(&t1) {
return nil, p.err
}
t = t1
}
return
}
// Apply name space translation to name n.
// The default name space (for Space=="")
// applies only to element names, not to attribute names.
func (p *Parser) translate(n *Name, isElementName bool) {
switch {
case n.Space == "xmlns":
return
case n.Space == "" && !isElementName:
return
case n.Space == "" && n.Local == "xmlns":
return
}
if v, ok := p.ns[n.Space]; ok {
n.Space = v
}
}
func (p *Parser) switchToReader(r io.Reader) {
// Get efficient byte at a time reader.
// Assume that if reader has its own
// ReadByte, it's efficient enough.
// Otherwise, use bufio.
if rb, ok := r.(io.ByteReader); ok {
p.r = rb
} else {
p.r = bufio.NewReader(r)
}
}
// Parsing state - stack holds old name space translations
// and the current set of open elements. The translations to pop when
// ending a given tag are *below* it on the stack, which is
// more work but forced on us by XML.
type stack struct {
next *stack
kind int
name Name
ok bool
}
const (
stkStart = iota
stkNs
)
func (p *Parser) push(kind int) *stack {
s := p.free
if s != nil {
p.free = s.next
} else {
s = new(stack)
}
s.next = p.stk
s.kind = kind
p.stk = s
return s
}
func (p *Parser) pop() *stack {
s := p.stk
if s != nil {
p.stk = s.next
s.next = p.free
p.free = s
}
return s
}
// Record that we are starting an element with the given name.
func (p *Parser) pushElement(name Name) {
s := p.push(stkStart)
s.name = name
}
// Record that we are changing the value of ns[local].
// The old value is url, ok.
func (p *Parser) pushNs(local string, url string, ok bool) {
s := p.push(stkNs)
s.name.Local = local
s.name.Space = url
s.ok = ok
}
// Creates a SyntaxError with the current line number.
func (p *Parser) syntaxError(msg string) os.Error {
return &SyntaxError{Msg: msg, Line: p.line}
}
// Record that we are ending an element with the given name.
// The name must match the record at the top of the stack,
// which must be a pushElement record.
// After popping the element, apply any undo records from
// the stack to restore the name translations that existed
// before we saw this element.
func (p *Parser) popElement(t *EndElement) bool {
s := p.pop()
name := t.Name
switch {
case s == nil || s.kind != stkStart:
p.err = p.syntaxError("unexpected end element </" + name.Local + ">")
return false
case s.name.Local != name.Local:
if !p.Strict {
p.needClose = true
p.toClose = t.Name
t.Name = s.name
return true
}
p.err = p.syntaxError("element <" + s.name.Local + "> closed by </" + name.Local + ">")
return false
case s.name.Space != name.Space:
p.err = p.syntaxError("element <" + s.name.Local + "> in space " + s.name.Space +
"closed by </" + name.Local + "> in space " + name.Space)
return false
}
// Pop stack until a Start is on the top, undoing the
// translations that were associated with the element we just closed.
for p.stk != nil && p.stk.kind != stkStart {
s := p.pop()
p.ns[s.name.Local] = s.name.Space, s.ok
}
return true
}
// If the top element on the stack is autoclosing and
// t is not the end tag, invent the end tag.
func (p *Parser) autoClose(t Token) (Token, bool) {
if p.stk == nil || p.stk.kind != stkStart {
return nil, false
}
name := strings.ToLower(p.stk.name.Local)
for _, s := range p.AutoClose {
if strings.ToLower(s) == name {
// This one should be auto closed if t doesn't close it.
et, ok := t.(EndElement)
if !ok || et.Name.Local != name {
return EndElement{p.stk.name}, true
}
break
}
}
return nil, false
}
// RawToken is like Token but does not verify that
// start and end elements match and does not translate
// name space prefixes to their corresponding URLs.
func (p *Parser) RawToken() (Token, os.Error) {
if p.err != nil {
return nil, p.err
}
if p.needClose {
// The last element we read was self-closing and
// we returned just the StartElement half.
// Return the EndElement half now.
p.needClose = false
return EndElement{p.toClose}, nil
}
b, ok := p.getc()
if !ok {
return nil, p.err
}
if b != '<' {
// Text section.
p.ungetc(b)
data := p.text(-1, false)
if data == nil {
return nil, p.err
}
return CharData(data), nil
}
if b, ok = p.mustgetc(); !ok {
return nil, p.err
}
switch b {
case '/':
// </: End element
var name Name
if name, ok = p.nsname(); !ok {
if p.err == nil {
p.err = p.syntaxError("expected element name after </")
}
return nil, p.err
}
p.space()
if b, ok = p.mustgetc(); !ok {
return nil, p.err
}
if b != '>' {
p.err = p.syntaxError("invalid characters between </" + name.Local + " and >")
return nil, p.err
}
return EndElement{name}, nil
case '?':
// <?: Processing instruction.
// TODO(rsc): Should parse the <?xml declaration to make sure
// the version is 1.0 and the encoding is UTF-8.
var target string
if target, ok = p.name(); !ok {
if p.err == nil {
p.err = p.syntaxError("expected target name after <?")
}
return nil, p.err
}
p.space()
p.buf.Reset()
var b0 byte
for {
if b, ok = p.mustgetc(); !ok {
return nil, p.err
}
p.buf.WriteByte(b)
if b0 == '?' && b == '>' {
break
}
b0 = b
}
data := p.buf.Bytes()
data = data[0 : len(data)-2] // chop ?>
if target == "xml" {
enc := procInstEncoding(string(data))
if enc != "" && enc != "utf-8" && enc != "UTF-8" {
if p.CharsetReader == nil {
p.err = fmt.Errorf("xml: encoding %q declared but Parser.CharsetReader is nil", enc)
return nil, p.err
}
newr, err := p.CharsetReader(enc, p.r.(io.Reader))
if err != nil {
p.err = fmt.Errorf("xml: opening charset %q: %v", enc, err)
return nil, p.err
}
if newr == nil {
panic("CharsetReader returned a nil Reader for charset " + enc)
}
p.switchToReader(newr)
}
}
return ProcInst{target, data}, nil
case '!':
// <!: Maybe comment, maybe CDATA.
if b, ok = p.mustgetc(); !ok {
return nil, p.err
}
switch b {
case '-': // <!-
// Probably <!-- for a comment.
if b, ok = p.mustgetc(); !ok {
return nil, p.err
}
if b != '-' {
p.err = p.syntaxError("invalid sequence <!- not part of <!--")
return nil, p.err
}
// Look for terminator.
p.buf.Reset()
var b0, b1 byte
for {
if b, ok = p.mustgetc(); !ok {
return nil, p.err
}
p.buf.WriteByte(b)
if b0 == '-' && b1 == '-' && b == '>' {
break
}
b0, b1 = b1, b
}
data := p.buf.Bytes()
data = data[0 : len(data)-3] // chop -->
return Comment(data), nil
case '[': // <![
// Probably <![CDATA[.
for i := 0; i < 6; i++ {
if b, ok = p.mustgetc(); !ok {
return nil, p.err
}
if b != "CDATA["[i] {
p.err = p.syntaxError("invalid <![ sequence")
return nil, p.err
}
}
// Have <![CDATA[. Read text until ]]>.
data := p.text(-1, true)
if data == nil {
return nil, p.err
}
return CharData(data), nil
}
// Probably a directive: <!DOCTYPE ...>, <!ENTITY ...>, etc.
// We don't care, but accumulate for caller. Quoted angle
// brackets do not count for nesting.
p.buf.Reset()
p.buf.WriteByte(b)
inquote := uint8(0)
depth := 0
for {
if b, ok = p.mustgetc(); !ok {
return nil, p.err
}
if inquote == 0 && b == '>' && depth == 0 {
break
}
p.buf.WriteByte(b)
switch {
case b == inquote:
inquote = 0
case inquote != 0:
// in quotes, no special action
case b == '\'' || b == '"':
inquote = b
case b == '>' && inquote == 0:
depth--
case b == '<' && inquote == 0:
depth++
}
}
return Directive(p.buf.Bytes()), nil
}
// Must be an open element like <a href="foo">
p.ungetc(b)
var (
name Name
empty bool
attr []Attr
)
if name, ok = p.nsname(); !ok {
if p.err == nil {
p.err = p.syntaxError("expected element name after <")
}
return nil, p.err
}
attr = make([]Attr, 0, 4)
for {
p.space()
if b, ok = p.mustgetc(); !ok {
return nil, p.err
}
if b == '/' {
empty = true
if b, ok = p.mustgetc(); !ok {
return nil, p.err
}
if b != '>' {
p.err = p.syntaxError("expected /> in element")
return nil, p.err
}
break
}
if b == '>' {
break
}
p.ungetc(b)
n := len(attr)
if n >= cap(attr) {
nattr := make([]Attr, n, 2*cap(attr))
copy(nattr, attr)
attr = nattr
}
attr = attr[0 : n+1]
a := &attr[n]
if a.Name, ok = p.nsname(); !ok {
if p.err == nil {
p.err = p.syntaxError("expected attribute name in element")
}
return nil, p.err
}
p.space()
if b, ok = p.mustgetc(); !ok {
return nil, p.err
}
if b != '=' {
if p.Strict {
p.err = p.syntaxError("attribute name without = in element")
return nil, p.err
} else {
p.ungetc(b)
a.Value = a.Name.Local
}
} else {
p.space()
data := p.attrval()
if data == nil {
return nil, p.err
}
a.Value = string(data)
}
}
if empty {
p.needClose = true
p.toClose = name
}
return StartElement{name, attr}, nil
}
func (p *Parser) attrval() []byte {
b, ok := p.mustgetc()
if !ok {
return nil
}
// Handle quoted attribute values
if b == '"' || b == '\'' {
return p.text(int(b), false)
}
// Handle unquoted attribute values for strict parsers
if p.Strict {
p.err = p.syntaxError("unquoted or missing attribute value in element")
return nil
}
// Handle unquoted attribute values for unstrict parsers
p.ungetc(b)
p.buf.Reset()
for {
b, ok = p.mustgetc()
if !ok {
return nil
}
// http://www.w3.org/TR/REC-html40/intro/sgmltut.html#h-3.2.2
if 'a' <= b && b <= 'z' || 'A' <= b && b <= 'Z' ||
'0' <= b && b <= '9' || b == '_' || b == ':' || b == '-' {
p.buf.WriteByte(b)
} else {
p.ungetc(b)
break
}
}
return p.buf.Bytes()
}
// Skip spaces if any
func (p *Parser) space() {
for {
b, ok := p.getc()
if !ok {
return
}
switch b {
case ' ', '\r', '\n', '\t':
default:
p.ungetc(b)
return
}
}
}
// Read a single byte.
// If there is no byte to read, return ok==false
// and leave the error in p.err.
// Maintain line number.
func (p *Parser) getc() (b byte, ok bool) {
if p.err != nil {
return 0, false
}
if p.nextByte >= 0 {
b = byte(p.nextByte)
p.nextByte = -1
} else {
b, p.err = p.r.ReadByte()
if p.err != nil {
return 0, false
}
if p.saved != nil {
p.saved.WriteByte(b)
}
}
if b == '\n' {
p.line++
}
return b, true
}
// Return saved offset.
// If we did ungetc (nextByte >= 0), have to back up one.
func (p *Parser) savedOffset() int {
n := p.saved.Len()
if p.nextByte >= 0 {
n--
}
return n
}
// Must read a single byte.
// If there is no byte to read,
// set p.err to SyntaxError("unexpected EOF")
// and return ok==false
func (p *Parser) mustgetc() (b byte, ok bool) {
if b, ok = p.getc(); !ok {
if p.err == os.EOF {
p.err = p.syntaxError("unexpected EOF")
}
}
return
}
// Unread a single byte.
func (p *Parser) ungetc(b byte) {
if b == '\n' {
p.line--
}
p.nextByte = int(b)
}
var entity = map[string]int{
"lt": '<',
"gt": '>',
"amp": '&',
"apos": '\'',
"quot": '"',
}
// Read plain text section (XML calls it character data).
// If quote >= 0, we are in a quoted string and need to find the matching quote.
// If cdata == true, we are in a <![CDATA[ section and need to find ]]>.
// On failure return nil and leave the error in p.err.
func (p *Parser) text(quote int, cdata bool) []byte {
var b0, b1 byte
var trunc int
p.buf.Reset()
Input:
for {
b, ok := p.getc()
if !ok {
if cdata {
if p.err == os.EOF {
p.err = p.syntaxError("unexpected EOF in CDATA section")
}
return nil
}
break Input
}
// <![CDATA[ section ends with ]]>.
// It is an error for ]]> to appear in ordinary text.
if b0 == ']' && b1 == ']' && b == '>' {
if cdata {
trunc = 2
break Input
}
p.err = p.syntaxError("unescaped ]]> not in CDATA section")
return nil
}
// Stop reading text if we see a <.
if b == '<' && !cdata {
if quote >= 0 {
p.err = p.syntaxError("unescaped < inside quoted string")
return nil
}
p.ungetc('<')
break Input
}
if quote >= 0 && b == byte(quote) {
break Input
}
if b == '&' && !cdata {
// Read escaped character expression up to semicolon.
// XML in all its glory allows a document to define and use
// its own character names with <!ENTITY ...> directives.
// Parsers are required to recognize lt, gt, amp, apos, and quot
// even if they have not been declared. That's all we allow.
var i int
for i = 0; i < len(p.tmp); i++ {
var ok bool
p.tmp[i], ok = p.getc()
if !ok {
if p.err == os.EOF {
p.err = p.syntaxError("unexpected EOF")
}
return nil
}
c := p.tmp[i]
if c == ';' {
break
}
if 'a' <= c && c <= 'z' ||
'A' <= c && c <= 'Z' ||
'0' <= c && c <= '9' ||
c == '_' || c == '#' {
continue
}
p.ungetc(c)
break
}
s := string(p.tmp[0:i])
if i >= len(p.tmp) {
if !p.Strict {
b0, b1 = 0, 0
p.buf.WriteByte('&')
p.buf.Write(p.tmp[0:i])
continue Input
}
p.err = p.syntaxError("character entity expression &" + s + "... too long")
return nil
}
var haveText bool
var text string
if i >= 2 && s[0] == '#' {
var n uint64
var err os.Error
if i >= 3 && s[1] == 'x' {
n, err = strconv.Btoui64(s[2:], 16)
} else {
n, err = strconv.Btoui64(s[1:], 10)
}
if err == nil && n <= unicode.MaxRune {
text = string(n)
haveText = true
}
} else {
if r, ok := entity[s]; ok {
text = string(r)
haveText = true
} else if p.Entity != nil {
text, haveText = p.Entity[s]
}
}
if !haveText {
if !p.Strict {
b0, b1 = 0, 0
p.buf.WriteByte('&')
p.buf.Write(p.tmp[0:i])
continue Input
}
p.err = p.syntaxError("invalid character entity &" + s + ";")
return nil
}
p.buf.Write([]byte(text))
b0, b1 = 0, 0
continue Input
}
p.buf.WriteByte(b)
b0, b1 = b1, b
}
data := p.buf.Bytes()
data = data[0 : len(data)-trunc]
// Inspect each rune for being a disallowed character.
buf := data
for len(buf) > 0 {
r, size := utf8.DecodeRune(buf)
if r == utf8.RuneError && size == 1 {
p.err = p.syntaxError("invalid UTF-8")
return nil
}
buf = buf[size:]
if !isInCharacterRange(r) {
p.err = p.syntaxError(fmt.Sprintf("illegal character code %U", r))
return nil
}
}
// Must rewrite \r and \r\n into \n.
w := 0
for r := 0; r < len(data); r++ {
b := data[r]
if b == '\r' {
if r+1 < len(data) && data[r+1] == '\n' {
continue
}
b = '\n'
}
data[w] = b
w++
}
return data[0:w]
}
// Decide whether the given rune is in the XML Character Range, per
// the Char production of http://www.xml.com/axml/testaxml.htm,
// Section 2.2 Characters.
func isInCharacterRange(rune int) (inrange bool) {
return rune == 0x09 ||
rune == 0x0A ||
rune == 0x0D ||
rune >= 0x20 && rune <= 0xDF77 ||
rune >= 0xE000 && rune <= 0xFFFD ||
rune >= 0x10000 && rune <= 0x10FFFF
}
// Get name space name: name with a : stuck in the middle.
// The part before the : is the name space identifier.
func (p *Parser) nsname() (name Name, ok bool) {
s, ok := p.name()
if !ok {
return
}
i := strings.Index(s, ":")
if i < 0 {
name.Local = s
} else {
name.Space = s[0:i]
name.Local = s[i+1:]
}
return name, true
}
// Get name: /first(first|second)*/
// Do not set p.err if the name is missing (unless unexpected EOF is received):
// let the caller provide better context.
func (p *Parser) name() (s string, ok bool) {
var b byte
if b, ok = p.mustgetc(); !ok {
return
}
// As a first approximation, we gather the bytes [A-Za-z_:.-\x80-\xFF]*
if b < utf8.RuneSelf && !isNameByte(b) {
p.ungetc(b)
return "", false
}
p.buf.Reset()
p.buf.WriteByte(b)
for {
if b, ok = p.mustgetc(); !ok {
return
}
if b < utf8.RuneSelf && !isNameByte(b) {
p.ungetc(b)
break
}
p.buf.WriteByte(b)
}
// Then we check the characters.
s = p.buf.String()
for i, c := range s {
if !unicode.Is(first, c) && (i == 0 || !unicode.Is(second, c)) {
p.err = p.syntaxError("invalid XML name: " + s)
return "", false
}
}
return s, true
}
func isNameByte(c byte) bool {
return 'A' <= c && c <= 'Z' ||
'a' <= c && c <= 'z' ||
'0' <= c && c <= '9' ||
c == '_' || c == ':' || c == '.' || c == '-'
}
// These tables were generated by cut and paste from Appendix B of
// the XML spec at http://www.xml.com/axml/testaxml.htm
// and then reformatting. First corresponds to (Letter | '_' | ':')
// and second corresponds to NameChar.
var first = &unicode.RangeTable{
R16: []unicode.Range16{
{0x003A, 0x003A, 1},
{0x0041, 0x005A, 1},
{0x005F, 0x005F, 1},
{0x0061, 0x007A, 1},
{0x00C0, 0x00D6, 1},
{0x00D8, 0x00F6, 1},
{0x00F8, 0x00FF, 1},
{0x0100, 0x0131, 1},
{0x0134, 0x013E, 1},
{0x0141, 0x0148, 1},
{0x014A, 0x017E, 1},
{0x0180, 0x01C3, 1},
{0x01CD, 0x01F0, 1},
{0x01F4, 0x01F5, 1},
{0x01FA, 0x0217, 1},
{0x0250, 0x02A8, 1},
{0x02BB, 0x02C1, 1},
{0x0386, 0x0386, 1},
{0x0388, 0x038A, 1},
{0x038C, 0x038C, 1},
{0x038E, 0x03A1, 1},
{0x03A3, 0x03CE, 1},
{0x03D0, 0x03D6, 1},
{0x03DA, 0x03E0, 2},
{0x03E2, 0x03F3, 1},
{0x0401, 0x040C, 1},
{0x040E, 0x044F, 1},
{0x0451, 0x045C, 1},
{0x045E, 0x0481, 1},
{0x0490, 0x04C4, 1},
{0x04C7, 0x04C8, 1},
{0x04CB, 0x04CC, 1},
{0x04D0, 0x04EB, 1},
{0x04EE, 0x04F5, 1},
{0x04F8, 0x04F9, 1},
{0x0531, 0x0556, 1},
{0x0559, 0x0559, 1},
{0x0561, 0x0586, 1},
{0x05D0, 0x05EA, 1},
{0x05F0, 0x05F2, 1},
{0x0621, 0x063A, 1},
{0x0641, 0x064A, 1},
{0x0671, 0x06B7, 1},
{0x06BA, 0x06BE, 1},
{0x06C0, 0x06CE, 1},
{0x06D0, 0x06D3, 1},
{0x06D5, 0x06D5, 1},
{0x06E5, 0x06E6, 1},
{0x0905, 0x0939, 1},
{0x093D, 0x093D, 1},
{0x0958, 0x0961, 1},
{0x0985, 0x098C, 1},
{0x098F, 0x0990, 1},
{0x0993, 0x09A8, 1},
{0x09AA, 0x09B0, 1},
{0x09B2, 0x09B2, 1},
{0x09B6, 0x09B9, 1},
{0x09DC, 0x09DD, 1},
{0x09DF, 0x09E1, 1},
{0x09F0, 0x09F1, 1},
{0x0A05, 0x0A0A, 1},
{0x0A0F, 0x0A10, 1},
{0x0A13, 0x0A28, 1},
{0x0A2A, 0x0A30, 1},
{0x0A32, 0x0A33, 1},
{0x0A35, 0x0A36, 1},
{0x0A38, 0x0A39, 1},
{0x0A59, 0x0A5C, 1},
{0x0A5E, 0x0A5E, 1},
{0x0A72, 0x0A74, 1},
{0x0A85, 0x0A8B, 1},
{0x0A8D, 0x0A8D, 1},
{0x0A8F, 0x0A91, 1},
{0x0A93, 0x0AA8, 1},
{0x0AAA, 0x0AB0, 1},
{0x0AB2, 0x0AB3, 1},
{0x0AB5, 0x0AB9, 1},
{0x0ABD, 0x0AE0, 0x23},
{0x0B05, 0x0B0C, 1},
{0x0B0F, 0x0B10, 1},
{0x0B13, 0x0B28, 1},
{0x0B2A, 0x0B30, 1},
{0x0B32, 0x0B33, 1},
{0x0B36, 0x0B39, 1},
{0x0B3D, 0x0B3D, 1},
{0x0B5C, 0x0B5D, 1},
{0x0B5F, 0x0B61, 1},
{0x0B85, 0x0B8A, 1},
{0x0B8E, 0x0B90, 1},
{0x0B92, 0x0B95, 1},
{0x0B99, 0x0B9A, 1},
{0x0B9C, 0x0B9C, 1},
{0x0B9E, 0x0B9F, 1},
{0x0BA3, 0x0BA4, 1},
{0x0BA8, 0x0BAA, 1},
{0x0BAE, 0x0BB5, 1},
{0x0BB7, 0x0BB9, 1},
{0x0C05, 0x0C0C, 1},
{0x0C0E, 0x0C10, 1},
{0x0C12, 0x0C28, 1},
{0x0C2A, 0x0C33, 1},
{0x0C35, 0x0C39, 1},
{0x0C60, 0x0C61, 1},
{0x0C85, 0x0C8C, 1},
{0x0C8E, 0x0C90, 1},
{0x0C92, 0x0CA8, 1},
{0x0CAA, 0x0CB3, 1},
{0x0CB5, 0x0CB9, 1},
{0x0CDE, 0x0CDE, 1},
{0x0CE0, 0x0CE1, 1},
{0x0D05, 0x0D0C, 1},
{0x0D0E, 0x0D10, 1},
{0x0D12, 0x0D28, 1},
{0x0D2A, 0x0D39, 1},
{0x0D60, 0x0D61, 1},
{0x0E01, 0x0E2E, 1},
{0x0E30, 0x0E30, 1},
{0x0E32, 0x0E33, 1},
{0x0E40, 0x0E45, 1},
{0x0E81, 0x0E82, 1},
{0x0E84, 0x0E84, 1},
{0x0E87, 0x0E88, 1},
{0x0E8A, 0x0E8D, 3},
{0x0E94, 0x0E97, 1},
{0x0E99, 0x0E9F, 1},
{0x0EA1, 0x0EA3, 1},
{0x0EA5, 0x0EA7, 2},
{0x0EAA, 0x0EAB, 1},
{0x0EAD, 0x0EAE, 1},
{0x0EB0, 0x0EB0, 1},
{0x0EB2, 0x0EB3, 1},
{0x0EBD, 0x0EBD, 1},
{0x0EC0, 0x0EC4, 1},
{0x0F40, 0x0F47, 1},
{0x0F49, 0x0F69, 1},
{0x10A0, 0x10C5, 1},
{0x10D0, 0x10F6, 1},
{0x1100, 0x1100, 1},
{0x1102, 0x1103, 1},
{0x1105, 0x1107, 1},
{0x1109, 0x1109, 1},
{0x110B, 0x110C, 1},
{0x110E, 0x1112, 1},
{0x113C, 0x1140, 2},
{0x114C, 0x1150, 2},
{0x1154, 0x1155, 1},
{0x1159, 0x1159, 1},
{0x115F, 0x1161, 1},
{0x1163, 0x1169, 2},
{0x116D, 0x116E, 1},
{0x1172, 0x1173, 1},
{0x1175, 0x119E, 0x119E - 0x1175},
{0x11A8, 0x11AB, 0x11AB - 0x11A8},
{0x11AE, 0x11AF, 1},
{0x11B7, 0x11B8, 1},
{0x11BA, 0x11BA, 1},
{0x11BC, 0x11C2, 1},
{0x11EB, 0x11F0, 0x11F0 - 0x11EB},
{0x11F9, 0x11F9, 1},
{0x1E00, 0x1E9B, 1},
{0x1EA0, 0x1EF9, 1},
{0x1F00, 0x1F15, 1},
{0x1F18, 0x1F1D, 1},
{0x1F20, 0x1F45, 1},
{0x1F48, 0x1F4D, 1},
{0x1F50, 0x1F57, 1},
{0x1F59, 0x1F5B, 0x1F5B - 0x1F59},
{0x1F5D, 0x1F5D, 1},
{0x1F5F, 0x1F7D, 1},
{0x1F80, 0x1FB4, 1},
{0x1FB6, 0x1FBC, 1},
{0x1FBE, 0x1FBE, 1},
{0x1FC2, 0x1FC4, 1},
{0x1FC6, 0x1FCC, 1},
{0x1FD0, 0x1FD3, 1},
{0x1FD6, 0x1FDB, 1},
{0x1FE0, 0x1FEC, 1},
{0x1FF2, 0x1FF4, 1},
{0x1FF6, 0x1FFC, 1},
{0x2126, 0x2126, 1},
{0x212A, 0x212B, 1},
{0x212E, 0x212E, 1},
{0x2180, 0x2182, 1},
{0x3007, 0x3007, 1},
{0x3021, 0x3029, 1},
{0x3041, 0x3094, 1},
{0x30A1, 0x30FA, 1},
{0x3105, 0x312C, 1},
{0x4E00, 0x9FA5, 1},
{0xAC00, 0xD7A3, 1},
},
}
var second = &unicode.RangeTable{
R16: []unicode.Range16{
{0x002D, 0x002E, 1},
{0x0030, 0x0039, 1},
{0x00B7, 0x00B7, 1},
{0x02D0, 0x02D1, 1},
{0x0300, 0x0345, 1},
{0x0360, 0x0361, 1},
{0x0387, 0x0387, 1},
{0x0483, 0x0486, 1},
{0x0591, 0x05A1, 1},
{0x05A3, 0x05B9, 1},
{0x05BB, 0x05BD, 1},
{0x05BF, 0x05BF, 1},
{0x05C1, 0x05C2, 1},
{0x05C4, 0x0640, 0x0640 - 0x05C4},
{0x064B, 0x0652, 1},
{0x0660, 0x0669, 1},
{0x0670, 0x0670, 1},
{0x06D6, 0x06DC, 1},
{0x06DD, 0x06DF, 1},
{0x06E0, 0x06E4, 1},
{0x06E7, 0x06E8, 1},
{0x06EA, 0x06ED, 1},
{0x06F0, 0x06F9, 1},
{0x0901, 0x0903, 1},
{0x093C, 0x093C, 1},
{0x093E, 0x094C, 1},
{0x094D, 0x094D, 1},
{0x0951, 0x0954, 1},
{0x0962, 0x0963, 1},
{0x0966, 0x096F, 1},
{0x0981, 0x0983, 1},
{0x09BC, 0x09BC, 1},
{0x09BE, 0x09BF, 1},
{0x09C0, 0x09C4, 1},
{0x09C7, 0x09C8, 1},
{0x09CB, 0x09CD, 1},
{0x09D7, 0x09D7, 1},
{0x09E2, 0x09E3, 1},
{0x09E6, 0x09EF, 1},
{0x0A02, 0x0A3C, 0x3A},
{0x0A3E, 0x0A3F, 1},
{0x0A40, 0x0A42, 1},
{0x0A47, 0x0A48, 1},
{0x0A4B, 0x0A4D, 1},
{0x0A66, 0x0A6F, 1},
{0x0A70, 0x0A71, 1},
{0x0A81, 0x0A83, 1},
{0x0ABC, 0x0ABC, 1},
{0x0ABE, 0x0AC5, 1},
{0x0AC7, 0x0AC9, 1},
{0x0ACB, 0x0ACD, 1},
{0x0AE6, 0x0AEF, 1},
{0x0B01, 0x0B03, 1},
{0x0B3C, 0x0B3C, 1},
{0x0B3E, 0x0B43, 1},
{0x0B47, 0x0B48, 1},
{0x0B4B, 0x0B4D, 1},
{0x0B56, 0x0B57, 1},
{0x0B66, 0x0B6F, 1},
{0x0B82, 0x0B83, 1},
{0x0BBE, 0x0BC2, 1},
{0x0BC6, 0x0BC8, 1},
{0x0BCA, 0x0BCD, 1},
{0x0BD7, 0x0BD7, 1},
{0x0BE7, 0x0BEF, 1},
{0x0C01, 0x0C03, 1},
{0x0C3E, 0x0C44, 1},
{0x0C46, 0x0C48, 1},
{0x0C4A, 0x0C4D, 1},
{0x0C55, 0x0C56, 1},
{0x0C66, 0x0C6F, 1},
{0x0C82, 0x0C83, 1},
{0x0CBE, 0x0CC4, 1},
{0x0CC6, 0x0CC8, 1},
{0x0CCA, 0x0CCD, 1},
{0x0CD5, 0x0CD6, 1},
{0x0CE6, 0x0CEF, 1},
{0x0D02, 0x0D03, 1},
{0x0D3E, 0x0D43, 1},
{0x0D46, 0x0D48, 1},
{0x0D4A, 0x0D4D, 1},
{0x0D57, 0x0D57, 1},
{0x0D66, 0x0D6F, 1},
{0x0E31, 0x0E31, 1},
{0x0E34, 0x0E3A, 1},
{0x0E46, 0x0E46, 1},
{0x0E47, 0x0E4E, 1},
{0x0E50, 0x0E59, 1},
{0x0EB1, 0x0EB1, 1},
{0x0EB4, 0x0EB9, 1},
{0x0EBB, 0x0EBC, 1},
{0x0EC6, 0x0EC6, 1},
{0x0EC8, 0x0ECD, 1},
{0x0ED0, 0x0ED9, 1},
{0x0F18, 0x0F19, 1},
{0x0F20, 0x0F29, 1},
{0x0F35, 0x0F39, 2},
{0x0F3E, 0x0F3F, 1},
{0x0F71, 0x0F84, 1},
{0x0F86, 0x0F8B, 1},
{0x0F90, 0x0F95, 1},
{0x0F97, 0x0F97, 1},
{0x0F99, 0x0FAD, 1},
{0x0FB1, 0x0FB7, 1},
{0x0FB9, 0x0FB9, 1},
{0x20D0, 0x20DC, 1},
{0x20E1, 0x3005, 0x3005 - 0x20E1},
{0x302A, 0x302F, 1},
{0x3031, 0x3035, 1},
{0x3099, 0x309A, 1},
{0x309D, 0x309E, 1},
{0x30FC, 0x30FE, 1},
},
}
// HTMLEntity is an entity map containing translations for the
// standard HTML entity characters.
var HTMLEntity = htmlEntity
var htmlEntity = map[string]string{
/*
hget http://www.w3.org/TR/html4/sgml/entities.html |
ssam '
,y /\&gt;/ x/\&lt;(.|\n)+/ s/\n/ /g
,x v/^\&lt;!ENTITY/d
,s/\&lt;!ENTITY ([^ ]+) .*U\+([0-9A-F][0-9A-F][0-9A-F][0-9A-F]) .+/ "\1": "\\u\2",/g
'
*/
"nbsp": "\u00A0",
"iexcl": "\u00A1",
"cent": "\u00A2",
"pound": "\u00A3",
"curren": "\u00A4",
"yen": "\u00A5",
"brvbar": "\u00A6",
"sect": "\u00A7",
"uml": "\u00A8",
"copy": "\u00A9",
"ordf": "\u00AA",
"laquo": "\u00AB",
"not": "\u00AC",
"shy": "\u00AD",
"reg": "\u00AE",
"macr": "\u00AF",
"deg": "\u00B0",
"plusmn": "\u00B1",
"sup2": "\u00B2",
"sup3": "\u00B3",
"acute": "\u00B4",
"micro": "\u00B5",
"para": "\u00B6",
"middot": "\u00B7",
"cedil": "\u00B8",
"sup1": "\u00B9",
"ordm": "\u00BA",
"raquo": "\u00BB",
"frac14": "\u00BC",
"frac12": "\u00BD",
"frac34": "\u00BE",
"iquest": "\u00BF",
"Agrave": "\u00C0",
"Aacute": "\u00C1",
"Acirc": "\u00C2",
"Atilde": "\u00C3",
"Auml": "\u00C4",
"Aring": "\u00C5",
"AElig": "\u00C6",
"Ccedil": "\u00C7",
"Egrave": "\u00C8",
"Eacute": "\u00C9",
"Ecirc": "\u00CA",
"Euml": "\u00CB",
"Igrave": "\u00CC",
"Iacute": "\u00CD",
"Icirc": "\u00CE",
"Iuml": "\u00CF",
"ETH": "\u00D0",
"Ntilde": "\u00D1",
"Ograve": "\u00D2",
"Oacute": "\u00D3",
"Ocirc": "\u00D4",
"Otilde": "\u00D5",
"Ouml": "\u00D6",
"times": "\u00D7",
"Oslash": "\u00D8",
"Ugrave": "\u00D9",
"Uacute": "\u00DA",
"Ucirc": "\u00DB",
"Uuml": "\u00DC",
"Yacute": "\u00DD",
"THORN": "\u00DE",
"szlig": "\u00DF",
"agrave": "\u00E0",
"aacute": "\u00E1",
"acirc": "\u00E2",
"atilde": "\u00E3",
"auml": "\u00E4",
"aring": "\u00E5",
"aelig": "\u00E6",
"ccedil": "\u00E7",
"egrave": "\u00E8",
"eacute": "\u00E9",
"ecirc": "\u00EA",
"euml": "\u00EB",
"igrave": "\u00EC",
"iacute": "\u00ED",
"icirc": "\u00EE",
"iuml": "\u00EF",
"eth": "\u00F0",
"ntilde": "\u00F1",
"ograve": "\u00F2",
"oacute": "\u00F3",
"ocirc": "\u00F4",
"otilde": "\u00F5",
"ouml": "\u00F6",
"divide": "\u00F7",
"oslash": "\u00F8",
"ugrave": "\u00F9",
"uacute": "\u00FA",
"ucirc": "\u00FB",
"uuml": "\u00FC",
"yacute": "\u00FD",
"thorn": "\u00FE",
"yuml": "\u00FF",
"fnof": "\u0192",
"Alpha": "\u0391",
"Beta": "\u0392",
"Gamma": "\u0393",
"Delta": "\u0394",
"Epsilon": "\u0395",
"Zeta": "\u0396",
"Eta": "\u0397",
"Theta": "\u0398",
"Iota": "\u0399",
"Kappa": "\u039A",
"Lambda": "\u039B",
"Mu": "\u039C",
"Nu": "\u039D",
"Xi": "\u039E",
"Omicron": "\u039F",
"Pi": "\u03A0",
"Rho": "\u03A1",
"Sigma": "\u03A3",
"Tau": "\u03A4",
"Upsilon": "\u03A5",
"Phi": "\u03A6",
"Chi": "\u03A7",
"Psi": "\u03A8",
"Omega": "\u03A9",
"alpha": "\u03B1",
"beta": "\u03B2",
"gamma": "\u03B3",
"delta": "\u03B4",
"epsilon": "\u03B5",
"zeta": "\u03B6",
"eta": "\u03B7",
"theta": "\u03B8",
"iota": "\u03B9",
"kappa": "\u03BA",
"lambda": "\u03BB",
"mu": "\u03BC",
"nu": "\u03BD",
"xi": "\u03BE",
"omicron": "\u03BF",
"pi": "\u03C0",
"rho": "\u03C1",
"sigmaf": "\u03C2",
"sigma": "\u03C3",
"tau": "\u03C4",
"upsilon": "\u03C5",
"phi": "\u03C6",
"chi": "\u03C7",
"psi": "\u03C8",
"omega": "\u03C9",
"thetasym": "\u03D1",
"upsih": "\u03D2",
"piv": "\u03D6",
"bull": "\u2022",
"hellip": "\u2026",
"prime": "\u2032",
"Prime": "\u2033",
"oline": "\u203E",
"frasl": "\u2044",
"weierp": "\u2118",
"image": "\u2111",
"real": "\u211C",
"trade": "\u2122",
"alefsym": "\u2135",
"larr": "\u2190",
"uarr": "\u2191",
"rarr": "\u2192",
"darr": "\u2193",
"harr": "\u2194",
"crarr": "\u21B5",
"lArr": "\u21D0",
"uArr": "\u21D1",
"rArr": "\u21D2",
"dArr": "\u21D3",
"hArr": "\u21D4",
"forall": "\u2200",
"part": "\u2202",
"exist": "\u2203",
"empty": "\u2205",
"nabla": "\u2207",
"isin": "\u2208",
"notin": "\u2209",
"ni": "\u220B",
"prod": "\u220F",
"sum": "\u2211",
"minus": "\u2212",
"lowast": "\u2217",
"radic": "\u221A",
"prop": "\u221D",
"infin": "\u221E",
"ang": "\u2220",
"and": "\u2227",
"or": "\u2228",
"cap": "\u2229",
"cup": "\u222A",
"int": "\u222B",
"there4": "\u2234",
"sim": "\u223C",
"cong": "\u2245",
"asymp": "\u2248",
"ne": "\u2260",
"equiv": "\u2261",
"le": "\u2264",
"ge": "\u2265",
"sub": "\u2282",
"sup": "\u2283",
"nsub": "\u2284",
"sube": "\u2286",
"supe": "\u2287",
"oplus": "\u2295",
"otimes": "\u2297",
"perp": "\u22A5",
"sdot": "\u22C5",
"lceil": "\u2308",
"rceil": "\u2309",
"lfloor": "\u230A",
"rfloor": "\u230B",
"lang": "\u2329",
"rang": "\u232A",
"loz": "\u25CA",
"spades": "\u2660",
"clubs": "\u2663",
"hearts": "\u2665",
"diams": "\u2666",
"quot": "\u0022",
"amp": "\u0026",
"lt": "\u003C",
"gt": "\u003E",
"OElig": "\u0152",
"oelig": "\u0153",
"Scaron": "\u0160",
"scaron": "\u0161",
"Yuml": "\u0178",
"circ": "\u02C6",
"tilde": "\u02DC",
"ensp": "\u2002",
"emsp": "\u2003",
"thinsp": "\u2009",
"zwnj": "\u200C",
"zwj": "\u200D",
"lrm": "\u200E",
"rlm": "\u200F",
"ndash": "\u2013",
"mdash": "\u2014",
"lsquo": "\u2018",
"rsquo": "\u2019",
"sbquo": "\u201A",
"ldquo": "\u201C",
"rdquo": "\u201D",
"bdquo": "\u201E",
"dagger": "\u2020",
"Dagger": "\u2021",
"permil": "\u2030",
"lsaquo": "\u2039",
"rsaquo": "\u203A",
"euro": "\u20AC",
}
// HTMLAutoClose is the set of HTML elements that
// should be considered to close automatically.
var HTMLAutoClose = htmlAutoClose
var htmlAutoClose = []string{
/*
hget http://www.w3.org/TR/html4/loose.dtd |
9 sed -n 's/<!ELEMENT (.*) - O EMPTY.+/ "\1",/p' | tr A-Z a-z
*/
"basefont",
"br",
"area",
"link",
"img",
"param",
"hr",
"input",
"col ",
"frame",
"isindex",
"base",
"meta",
}
var (
esc_quot = []byte("&#34;") // shorter than "&quot;"
esc_apos = []byte("&#39;") // shorter than "&apos;"
esc_amp = []byte("&amp;")
esc_lt = []byte("&lt;")
esc_gt = []byte("&gt;")
)
// Escape writes to w the properly escaped XML equivalent
// of the plain text data s.
func Escape(w io.Writer, s []byte) {
var esc []byte
last := 0
for i, c := range s {
switch c {
case '"':
esc = esc_quot
case '\'':
esc = esc_apos
case '&':
esc = esc_amp
case '<':
esc = esc_lt
case '>':
esc = esc_gt
default:
continue
}
w.Write(s[last:i])
w.Write(esc)
last = i + 1
}
w.Write(s[last:])
}
// procInstEncoding parses the `encoding="..."` or `encoding='...'`
// value out of the provided string, returning "" if not found.
func procInstEncoding(s string) string {
// TODO: this parsing is somewhat lame and not exact.
// It works for all actual cases, though.
idx := strings.Index(s, "encoding=")
if idx == -1 {
return ""
}
v := s[idx+len("encoding="):]
if v == "" {
return ""
}
if v[0] != '\'' && v[0] != '"' {
return ""
}
idx = strings.IndexRune(v[1:], int(v[0]))
if idx == -1 {
return ""
}
return v[1 : idx+1]
}