// 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: https://www.xml.com/axml/testaxml.htm
// XML name spaces: https://www.w3.org/TR/REC-xml-names/
// TODO(rsc):
// Test error handling.
import (
"bufio"
"bytes"
"errors"
"fmt"
"io"
"strconv"
"strings"
"unicode"
"unicode/utf8"
)
// A SyntaxError represents a syntax error in the XML input stream.
type SyntaxError struct {
Msg string
Line int
}
func (e *SyntaxError) Error() 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 Decoder.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
}
// Copy creates a new copy of StartElement.
func (e StartElement) Copy() StartElement {
attrs := make([]Attr, len(e.Attr))
copy(attrs, e.Attr)
e.Attr = attrs
return e
}
// End returns the corresponding XML end element.
func (e StartElement) End() EndElement {
return EndElement{e.Name}
}
// 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// in which XML escape sequences have been replaced by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
}
// Copy creates a new copy of CharData.
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
// Copy creates a new copy of Comment.
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
}
// Copy creates a new copy of ProcInst.
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
// Copy creates a new copy of Directive.
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 TokenReader is anything that can decode a stream of XML tokens, including a
// Decoder.
//
// When Token encounters an error or end-of-file condition after successfully
// reading a token, it returns the token. It may return the (non-nil) error from
// the same call or return the error (and a nil token) from a subsequent call.
// An instance of this general case is that a TokenReader returning a non-nil
// token at the end of the token stream may return either io.EOF or a nil error.
// The next Read should return nil, io.EOF.
//
// Implementations of Token are discouraged from returning a nil token with a
// nil error. Callers should treat a return of nil, nil as indicating that
// nothing happened; in particular it does not indicate EOF.
type TokenReader interface {
Token() (Token, error)
}
// A Decoder represents an XML parser reading a particular input stream.
// The parser assumes that its input is encoded in UTF-8.
type Decoder 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:
//
// d.Strict = false
// d.AutoClose = xml.HTMLAutoClose
// d.Entity = xml.HTMLEntity
//
// creates a parser that can handle typical HTML.
//
// Strict mode does not enforce the requirements of the XML name spaces TR.
// In particular it does not reject name space tags using undefined prefixes.
// Such tags are recorded with the unknown prefix as the name space URL.
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
// CharsetReader's result values must be non-nil.
CharsetReader func(charset string, input io.Reader) (io.Reader, error)
// DefaultSpace sets the default name space used for unadorned tags,
// as if the entire XML stream were wrapped in an element containing
// the attribute xmlns="DefaultSpace".
DefaultSpace string
r io.ByteReader
t TokenReader
buf bytes.Buffer
saved *bytes.Buffer
stk *stack
free *stack
needClose bool
toClose Name
nextToken Token
nextByte int
ns map[string]string
err error
line int
offset int64
unmarshalDepth int
}
// NewDecoder creates a new XML parser reading from r.
// If r does not implement io.ByteReader, NewDecoder will
// do its own buffering.
func NewDecoder(r io.Reader) *Decoder {
d := &Decoder{
ns: make(map[string]string),
nextByte: -1,
line: 1,
Strict: true,
}
d.switchToReader(r)
return d
}
// NewTokenDecoder creates a new XML parser using an underlying token stream.
func NewTokenDecoder(t TokenReader) *Decoder {
// Is it already a Decoder?
if d, ok := t.(*Decoder); ok {
return d
}
d := &Decoder{
ns: make(map[string]string),
t: t,
nextByte: -1,
line: 1,
Strict: true,
}
return d
}
// Token returns the next XML token in the input stream.
// At the end of the input stream, Token returns nil, io.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
// or EOF before all expected end elements,
// it will return an error.
//
// Token implements XML name spaces as described by
// https://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 (d *Decoder) Token() (Token, error) {
var t Token
var err error
if d.stk != nil && d.stk.kind == stkEOF {
return nil, io.EOF
}
if d.nextToken != nil {
t = d.nextToken
d.nextToken = nil
} else if t, err = d.rawToken(); err != nil {
if err == io.EOF && d.stk != nil && d.stk.kind != stkEOF {
err = d.syntaxError("unexpected EOF")
}
return t, err
}
if !d.Strict {
if t1, ok := d.autoClose(t); ok {
d.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 == xmlnsPrefix {
v, ok := d.ns[a.Name.Local]
d.pushNs(a.Name.Local, v, ok)
d.ns[a.Name.Local] = a.Value
}
if a.Name.Space == "" && a.Name.Local == xmlnsPrefix {
// Default space for untagged names
v, ok := d.ns[""]
d.pushNs("", v, ok)
d.ns[""] = a.Value
}
}
d.translate(&t1.Name, true)
for i := range t1.Attr {
d.translate(&t1.Attr[i].Name, false)
}
d.pushElement(t1.Name)
t = t1
case EndElement:
d.translate(&t1.Name, true)
if !d.popElement(&t1) {
return nil, d.err
}
t = t1
}
return t, err
}
const (
xmlURL = "http://www.w3.org/XML/1998/namespace"
xmlnsPrefix = "xmlns"
xmlPrefix = "xml"
)
// Apply name space translation to name n.
// The default name space (for Space=="")
// applies only to element names, not to attribute names.
func (d *Decoder) translate(n *Name, isElementName bool) {
switch {
case n.Space == xmlnsPrefix:
return
case n.Space == "" && !isElementName:
return
case n.Space == xmlPrefix:
n.Space = xmlURL
case n.Space == "" && n.Local == xmlnsPrefix:
return
}
if v, ok := d.ns[n.Space]; ok {
n.Space = v
} else if n.Space == "" {
n.Space = d.DefaultSpace
}
}
func (d *Decoder) 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 {
d.r = rb
} else {
d.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
stkEOF
)
func (d *Decoder) push(kind int) *stack {
s := d.free
if s != nil {
d.free = s.next
} else {
s = new(stack)
}
s.next = d.stk
s.kind = kind
d.stk = s
return s
}
func (d *Decoder) pop() *stack {
s := d.stk
if s != nil {
d.stk = s.next
s.next = d.free
d.free = s
}
return s
}
// Record that after the current element is finished
// (that element is already pushed on the stack)
// Token should return EOF until popEOF is called.
func (d *Decoder) pushEOF() {
// Walk down stack to find Start.
// It might not be the top, because there might be stkNs
// entries above it.
start := d.stk
for start.kind != stkStart {
start = start.next
}
// The stkNs entries below a start are associated with that
// element too; skip over them.
for start.next != nil && start.next.kind == stkNs {
start = start.next
}
s := d.free
if s != nil {
d.free = s.next
} else {
s = new(stack)
}
s.kind = stkEOF
s.next = start.next
start.next = s
}
// Undo a pushEOF.
// The element must have been finished, so the EOF should be at the top of the stack.
func (d *Decoder) popEOF() bool {
if d.stk == nil || d.stk.kind != stkEOF {
return false
}
d.pop()
return true
}
// Record that we are starting an element with the given name.
func (d *Decoder) pushElement(name Name) {
s := d.push(stkStart)
s.name = name
}
// Record that we are changing the value of ns[local].
// The old value is url, ok.
func (d *Decoder) pushNs(local string, url string, ok bool) {
s := d.push(stkNs)
s.name.Local = local
s.name.Space = url
s.ok = ok
}
// Creates a SyntaxError with the current line number.
func (d *Decoder) syntaxError(msg string) error {
return &SyntaxError{Msg: msg, Line: d.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 (d *Decoder) popElement(t *EndElement) bool {
s := d.pop()
name := t.Name
switch {
case s == nil || s.kind != stkStart:
d.err = d.syntaxError("unexpected end element </" + name.Local + ">")
return false
case s.name.Local != name.Local:
if !d.Strict {
d.needClose = true
d.toClose = t.Name
t.Name = s.name
return true
}
d.err = d.syntaxError("element <" + s.name.Local + "> closed by </" + name.Local + ">")
return false
case s.name.Space != name.Space:
d.err = d.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 or EOF is on the top, undoing the
// translations that were associated with the element we just closed.
for d.stk != nil && d.stk.kind != stkStart && d.stk.kind != stkEOF {
s := d.pop()
if s.ok {
d.ns[s.name.Local] = s.name.Space
} else {
delete(d.ns, s.name.Local)
}
}
return true
}
// If the top element on the stack is autoclosing and
// t is not the end tag, invent the end tag.
func (d *Decoder) autoClose(t Token) (Token, bool) {
if d.stk == nil || d.stk.kind != stkStart {
return nil, false
}
name := strings.ToLower(d.stk.name.Local)
for _, s := range d.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{d.stk.name}, true
}
break
}
}
return nil, false
}
var errRawToken = errors.New("xml: cannot use RawToken from UnmarshalXML method")
// 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 (d *Decoder) RawToken() (Token, error) {
if d.unmarshalDepth > 0 {
return nil, errRawToken
}
return d.rawToken()
}
func (d *Decoder) rawToken() (Token, error) {
if d.t != nil {
return d.t.Token()
}
if d.err != nil {
return nil, d.err
}
if d.needClose {
// The last element we read was self-closing and
// we returned just the StartElement half.
// Return the EndElement half now.
d.needClose = false
return EndElement{d.toClose}, nil
}
b, ok := d.getc()
if !ok {
return nil, d.err
}
if b != '<' {
// Text section.
d.ungetc(b)
data := d.text(-1, false)
if data == nil {
return nil, d.err
}
return CharData(data), nil
}
if b, ok = d.mustgetc(); !ok {
return nil, d.err
}
switch b {
case '/':
// </: End element
var name Name
if name, ok = d.nsname(); !ok {
if d.err == nil {
d.err = d.syntaxError("expected element name after </")
}
return nil, d.err
}
d.space()
if b, ok = d.mustgetc(); !ok {
return nil, d.err
}
if b != '>' {
d.err = d.syntaxError("invalid characters between </" + name.Local + " and >")
return nil, d.err
}
return EndElement{name}, nil
case '?':
// <?: Processing instruction.
var target string
if target, ok = d.name(); !ok {
if d.err == nil {
d.err = d.syntaxError("expected target name after <?")
}
return nil, d.err
}
d.space()
d.buf.Reset()
var b0 byte
for {
if b, ok = d.mustgetc(); !ok {
return nil, d.err
}
d.buf.WriteByte(b)
if b0 == '?' && b == '>' {
break
}
b0 = b
}
data := d.buf.Bytes()
data = data[0 : len(data)-2] // chop ?>
if target == "xml" {
content := string(data)
ver := procInst("version", content)
if ver != "" && ver != "1.0" {
d.err = fmt.Errorf("xml: unsupported version %q; only version 1.0 is supported", ver)
return nil, d.err
}
enc := procInst("encoding", content)
if enc != "" && enc != "utf-8" && enc != "UTF-8" && !strings.EqualFold(enc, "utf-8") {
if d.CharsetReader == nil {
d.err = fmt.Errorf("xml: encoding %q declared but Decoder.CharsetReader is nil", enc)
return nil, d.err
}
newr, err := d.CharsetReader(enc, d.r.(io.Reader))
if err != nil {
d.err = fmt.Errorf("xml: opening charset %q: %v", enc, err)
return nil, d.err
}
if newr == nil {
panic("CharsetReader returned a nil Reader for charset " + enc)
}
d.switchToReader(newr)
}
}
return ProcInst{target, data}, nil
case '!':
// <!: Maybe comment, maybe CDATA.
if b, ok = d.mustgetc(); !ok {
return nil, d.err
}
switch b {
case '-': // <!-
// Probably <!-- for a comment.
if b, ok = d.mustgetc(); !ok {
return nil, d.err
}
if b != '-' {
d.err = d.syntaxError("invalid sequence <!- not part of <!--")
return nil, d.err
}
// Look for terminator.
d.buf.Reset()
var b0, b1 byte
for {
if b, ok = d.mustgetc(); !ok {
return nil, d.err
}
d.buf.WriteByte(b)
if b0 == '-' && b1 == '-' {
if b != '>' {
d.err = d.syntaxError(
`invalid sequence "--" not allowed in comments`)
return nil, d.err
}
break
}
b0, b1 = b1, b
}
data := d.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 = d.mustgetc(); !ok {
return nil, d.err
}
if b != "CDATA["[i] {
d.err = d.syntaxError("invalid <![ sequence")
return nil, d.err
}
}
// Have <![CDATA[. Read text until ]]>.
data := d.text(-1, true)
if data == nil {
return nil, d.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.
d.buf.Reset()
d.buf.WriteByte(b)
inquote := uint8(0)
depth := 0
for {
if b, ok = d.mustgetc(); !ok {
return nil, d.err
}
if inquote == 0 && b == '>' && depth == 0 {
break
}
HandleB:
d.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:
// Look for <!-- to begin comment.
s := "!--"
for i := 0; i < len(s); i++ {
if b, ok = d.mustgetc(); !ok {
return nil, d.err
}
if b != s[i] {
for j := 0; j < i; j++ {
d.buf.WriteByte(s[j])
}
depth++
goto HandleB
}
}
// Remove < that was written above.
d.buf.Truncate(d.buf.Len() - 1)
// Look for terminator.
var b0, b1 byte
for {
if b, ok = d.mustgetc(); !ok {
return nil, d.err
}
if b0 == '-' && b1 == '-' && b == '>' {
break
}
b0, b1 = b1, b
}
}
}
return Directive(d.buf.Bytes()), nil
}
// Must be an open element like <a href="foo">
d.ungetc(b)
var (
name Name
empty bool
attr []Attr
)
if name, ok = d.nsname(); !ok {
if d.err == nil {
d.err = d.syntaxError("expected element name after <")
}
return nil, d.err
}
attr = []Attr{}
for {
d.space()
if b, ok = d.mustgetc(); !ok {
return nil, d.err
}
if b == '/' {
empty = true
if b, ok = d.mustgetc(); !ok {
return nil, d.err
}
if b != '>' {
d.err = d.syntaxError("expected /> in element")
return nil, d.err
}
break
}
if b == '>' {
break
}
d.ungetc(b)
a := Attr{}
if a.Name, ok = d.nsname(); !ok {
if d.err == nil {
d.err = d.syntaxError("expected attribute name in element")
}
return nil, d.err
}
d.space()
if b, ok = d.mustgetc(); !ok {
return nil, d.err
}
if b != '=' {
if d.Strict {
d.err = d.syntaxError("attribute name without = in element")
return nil, d.err
}
d.ungetc(b)
a.Value = a.Name.Local
} else {
d.space()
data := d.attrval()
if data == nil {
return nil, d.err
}
a.Value = string(data)
}
attr = append(attr, a)
}
if empty {
d.needClose = true
d.toClose = name
}
return StartElement{name, attr}, nil
}
func (d *Decoder) attrval() []byte {
b, ok := d.mustgetc()
if !ok {
return nil
}
// Handle quoted attribute values
if b == '"' || b == '\'' {
return d.text(int(b), false)
}
// Handle unquoted attribute values for strict parsers
if d.Strict {
d.err = d.syntaxError("unquoted or missing attribute value in element")
return nil
}
// Handle unquoted attribute values for unstrict parsers
d.ungetc(b)
d.buf.Reset()
for {
b, ok = d.mustgetc()
if !ok {
return nil
}
// https://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 == '-' {
d.buf.WriteByte(b)
} else {
d.ungetc(b)
break
}
}
return d.buf.Bytes()
}
// Skip spaces if any
func (d *Decoder) space() {
for {
b, ok := d.getc()
if !ok {
return
}
switch b {
case ' ', '\r', '\n', '\t':
default:
d.ungetc(b)
return
}
}
}
// Read a single byte.
// If there is no byte to read, return ok==false
// and leave the error in d.err.
// Maintain line number.
func (d *Decoder) getc() (b byte, ok bool) {
if d.err != nil {
return 0, false
}
if d.nextByte >= 0 {
b = byte(d.nextByte)
d.nextByte = -1
} else {
b, d.err = d.r.ReadByte()
if d.err != nil {
return 0, false
}
if d.saved != nil {
d.saved.WriteByte(b)
}
}
if b == '\n' {
d.line++
}
d.offset++
return b, true
}
// InputOffset returns the input stream byte offset of the current decoder position.
// The offset gives the location of the end of the most recently returned token
// and the beginning of the next token.
func (d *Decoder) InputOffset() int64 {
return d.offset
}
// Return saved offset.
// If we did ungetc (nextByte >= 0), have to back up one.
func (d *Decoder) savedOffset() int {
n := d.saved.Len()
if d.nextByte >= 0 {
n--
}
return n
}
// Must read a single byte.
// If there is no byte to read,
// set d.err to SyntaxError("unexpected EOF")
// and return ok==false
func (d *Decoder) mustgetc() (b byte, ok bool) {
if b, ok = d.getc(); !ok {
if d.err == io.EOF {
d.err = d.syntaxError("unexpected EOF")
}
}
return
}
// Unread a single byte.
func (d *Decoder) ungetc(b byte) {
if b == '\n' {
d.line--
}
d.nextByte = int(b)
d.offset--
}
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 d.err.
func (d *Decoder) text(quote int, cdata bool) []byte {
var b0, b1 byte
var trunc int
d.buf.Reset()
Input:
for {
b, ok := d.getc()
if !ok {
if cdata {
if d.err == io.EOF {
d.err = d.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
}
d.err = d.syntaxError("unescaped ]]> not in CDATA section")
return nil
}
// Stop reading text if we see a <.
if b == '<' && !cdata {
if quote >= 0 {
d.err = d.syntaxError("unescaped < inside quoted string")
return nil
}
d.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.
before := d.buf.Len()
d.buf.WriteByte('&')
var ok bool
var text string
var haveText bool
if b, ok = d.mustgetc(); !ok {
return nil
}
if b == '#' {
d.buf.WriteByte(b)
if b, ok = d.mustgetc(); !ok {
return nil
}
base := 10
if b == 'x' {
base = 16
d.buf.WriteByte(b)
if b, ok = d.mustgetc(); !ok {
return nil
}
}
start := d.buf.Len()
for '0' <= b && b <= '9' ||
base == 16 && 'a' <= b && b <= 'f' ||
base == 16 && 'A' <= b && b <= 'F' {
d.buf.WriteByte(b)
if b, ok = d.mustgetc(); !ok {
return nil
}
}
if b != ';' {
d.ungetc(b)
} else {
s := string(d.buf.Bytes()[start:])
d.buf.WriteByte(';')
n, err := strconv.ParseUint(s, base, 64)
if err == nil && n <= unicode.MaxRune {
text = string(n)
haveText = true
}
}
} else {
d.ungetc(b)
if !d.readName() {
if d.err != nil {
return nil
}
}
if b, ok = d.mustgetc(); !ok {
return nil
}
if b != ';' {
d.ungetc(b)
} else {
name := d.buf.Bytes()[before+1:]
d.buf.WriteByte(';')
if isName(name) {
s := string(name)
if r, ok := entity[s]; ok {
text = string(r)
haveText = true
} else if d.Entity != nil {
text, haveText = d.Entity[s]
}
}
}
}
if haveText {
d.buf.Truncate(before)
d.buf.Write([]byte(text))
b0, b1 = 0, 0
continue Input
}
if !d.Strict {
b0, b1 = 0, 0
continue Input
}
ent := string(d.buf.Bytes()[before:])
if ent[len(ent)-1] != ';' {
ent += " (no semicolon)"
}
d.err = d.syntaxError("invalid character entity " + ent)
return nil
}
// We must rewrite unescaped \r and \r\n into \n.
if b == '\r' {
d.buf.WriteByte('\n')
} else if b1 == '\r' && b == '\n' {
// Skip \r\n--we already wrote \n.
} else {
d.buf.WriteByte(b)
}
b0, b1 = b1, b
}
data := d.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 {
d.err = d.syntaxError("invalid UTF-8")
return nil
}
buf = buf[size:]
if !isInCharacterRange(r) {
d.err = d.syntaxError(fmt.Sprintf("illegal character code %U", r))
return nil
}
}
return data
}
// Decide whether the given rune is in the XML Character Range, per
// the Char production of https://www.xml.com/axml/testaxml.htm,
// Section 2.2 Characters.
func isInCharacterRange(r rune) (inrange bool) {
return r == 0x09 ||
r == 0x0A ||
r == 0x0D ||
r >= 0x20 && r <= 0xD7FF ||
r >= 0xE000 && r <= 0xFFFD ||
r >= 0x10000 && r <= 0x10FFFF
}
// Get name space name: name with a : stuck in the middle.
// The part before the : is the name space identifier.
func (d *Decoder) nsname() (name Name, ok bool) {
s, ok := d.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 d.err if the name is missing (unless unexpected EOF is received):
// let the caller provide better context.
func (d *Decoder) name() (s string, ok bool) {
d.buf.Reset()
if !d.readName() {
return "", false
}
// Now we check the characters.
b := d.buf.Bytes()
if !isName(b) {
d.err = d.syntaxError("invalid XML name: " + string(b))
return "", false
}
return string(b), true
}
// Read a name and append its bytes to d.buf.
// The name is delimited by any single-byte character not valid in names.
// All multi-byte characters are accepted; the caller must check their validity.
func (d *Decoder) readName() (ok bool) {
var b byte
if b, ok = d.mustgetc(); !ok {
return
}
if b < utf8.RuneSelf && !isNameByte(b) {
d.ungetc(b)
return false
}
d.buf.WriteByte(b)
for {
if b, ok = d.mustgetc(); !ok {
return
}
if b < utf8.RuneSelf && !isNameByte(b) {
d.ungetc(b)
break
}
d.buf.WriteByte(b)
}
return true
}
func isNameByte(c byte) bool {
return 'A' <= c && c <= 'Z' ||
'a' <= c && c <= 'z' ||
'0' <= c && c <= '9' ||
c == '_' || c == ':' || c == '.' || c == '-'
}
func isName(s []byte) bool {
if len(s) == 0 {
return false
}
c, n := utf8.DecodeRune(s)
if c == utf8.RuneError && n == 1 {
return false
}
if !unicode.Is(first, c) {
return false
}
for n < len(s) {
s = s[n:]
c, n = utf8.DecodeRune(s)
if c == utf8.RuneError && n == 1 {
return false
}
if !unicode.Is(first, c) && !unicode.Is(second, c) {
return false
}
}
return true
}
func isNameString(s string) bool {
if len(s) == 0 {
return false
}
c, n := utf8.DecodeRuneInString(s)
if c == utf8.RuneError && n == 1 {
return false
}
if !unicode.Is(first, c) {
return false
}
for n < len(s) {
s = s[n:]
c, n = utf8.DecodeRuneInString(s)
if c == utf8.RuneError && n == 1 {
return false
}
if !unicode.Is(first, c) && !unicode.Is(second, c) {
return false
}
}
return true
}
// These tables were generated by cut and paste from Appendix B of
// the XML spec at https://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.
//
// See the Decoder.Strict and Decoder.Entity fields' documentation.
var HTMLEntity map[string]string = htmlEntity
var htmlEntity = map[string]string{
/*
hget http://www.w3.org/TR/html4/sgml/entities.html |
ssam '
,y /\>/ x/\<(.|\n)+/ s/\n/ /g
,x v/^\<!ENTITY/d
,s/\<!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.
//
// See the Decoder.Strict and Decoder.Entity fields' documentation.
var HTMLAutoClose []string = 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 (
escQuot = []byte(""") // shorter than """
escApos = []byte("'") // shorter than "'"
escAmp = []byte("&")
escLT = []byte("<")
escGT = []byte(">")
escTab = []byte("	")
escNL = []byte("
")
escCR = []byte("
")
escFFFD = []byte("\uFFFD") // Unicode replacement character
)
// EscapeText writes to w the properly escaped XML equivalent
// of the plain text data s.
func EscapeText(w io.Writer, s []byte) error {
return escapeText(w, s, true)
}
// escapeText writes to w the properly escaped XML equivalent
// of the plain text data s. If escapeNewline is true, newline
// characters will be escaped.
func escapeText(w io.Writer, s []byte, escapeNewline bool) error {
var esc []byte
last := 0
for i := 0; i < len(s); {
r, width := utf8.DecodeRune(s[i:])
i += width
switch r {
case '"':
esc = escQuot
case '\'':
esc = escApos
case '&':
esc = escAmp
case '<':
esc = escLT
case '>':
esc = escGT
case '\t':
esc = escTab
case '\n':
if !escapeNewline {
continue
}
esc = escNL
case '\r':
esc = escCR
default:
if !isInCharacterRange(r) || (r == 0xFFFD && width == 1) {
esc = escFFFD
break
}
continue
}
if _, err := w.Write(s[last : i-width]); err != nil {
return err
}
if _, err := w.Write(esc); err != nil {
return err
}
last = i
}
_, err := w.Write(s[last:])
return err
}
// EscapeString writes to p the properly escaped XML equivalent
// of the plain text data s.
func (p *printer) EscapeString(s string) {
var esc []byte
last := 0
for i := 0; i < len(s); {
r, width := utf8.DecodeRuneInString(s[i:])
i += width
switch r {
case '"':
esc = escQuot
case '\'':
esc = escApos
case '&':
esc = escAmp
case '<':
esc = escLT
case '>':
esc = escGT
case '\t':
esc = escTab
case '\n':
esc = escNL
case '\r':
esc = escCR
default:
if !isInCharacterRange(r) || (r == 0xFFFD && width == 1) {
esc = escFFFD
break
}
continue
}
p.WriteString(s[last : i-width])
p.Write(esc)
last = i
}
p.WriteString(s[last:])
}
// Escape is like EscapeText but omits the error return value.
// It is provided for backwards compatibility with Go 1.0.
// Code targeting Go 1.1 or later should use EscapeText.
func Escape(w io.Writer, s []byte) {
EscapeText(w, s)
}
var (
cdataStart = []byte("<![CDATA[")
cdataEnd = []byte("]]>")
cdataEscape = []byte("]]]]><![CDATA[>")
)
// emitCDATA writes to w the CDATA-wrapped plain text data s.
// It escapes CDATA directives nested in s.
func emitCDATA(w io.Writer, s []byte) error {
if len(s) == 0 {
return nil
}
if _, err := w.Write(cdataStart); err != nil {
return err
}
for {
i := bytes.Index(s, cdataEnd)
if i >= 0 && i+len(cdataEnd) <= len(s) {
// Found a nested CDATA directive end.
if _, err := w.Write(s[:i]); err != nil {
return err
}
if _, err := w.Write(cdataEscape); err != nil {
return err
}
i += len(cdataEnd)
} else {
if _, err := w.Write(s); err != nil {
return err
}
break
}
s = s[i:]
}
_, err := w.Write(cdataEnd)
return err
}
// procInst parses the `param="..."` or `param='...'`
// value out of the provided string, returning "" if not found.
func procInst(param, s string) string {
// TODO: this parsing is somewhat lame and not exact.
// It works for all actual cases, though.
param = param + "="
idx := strings.Index(s, param)
if idx == -1 {
return ""
}
v := s[idx+len(param):]
if v == "" {
return ""
}
if v[0] != '\'' && v[0] != '"' {
return ""
}
idx = strings.IndexRune(v[1:], rune(v[0]))
if idx == -1 {
return ""
}
return v[1 : idx+1]
}