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-rw-r--r--gcc-4.8.1/libgo/go/exp/html/token.go1173
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diff --git a/gcc-4.8.1/libgo/go/exp/html/token.go b/gcc-4.8.1/libgo/go/exp/html/token.go
deleted file mode 100644
index f9a087b02..000000000
--- a/gcc-4.8.1/libgo/go/exp/html/token.go
+++ /dev/null
@@ -1,1173 +0,0 @@
-// 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"
- "exp/html/atom"
- "io"
- "strconv"
- "strings"
-)
-
-// A TokenType is the type of a Token.
-type TokenType uint32
-
-const (
- // ErrorToken means that an error occurred during tokenization.
- ErrorToken TokenType = iota
- // TextToken means a text node.
- TextToken
- // A StartTagToken looks like <a>.
- StartTagToken
- // An EndTagToken looks like </a>.
- EndTagToken
- // A SelfClosingTagToken tag looks like <br/>.
- SelfClosingTagToken
- // A CommentToken looks like <!--x-->.
- CommentToken
- // A DoctypeToken looks like <!DOCTYPE x>
- DoctypeToken
-)
-
-// String returns a string representation of the TokenType.
-func (t TokenType) String() string {
- switch t {
- case ErrorToken:
- return "Error"
- case TextToken:
- return "Text"
- case StartTagToken:
- return "StartTag"
- case EndTagToken:
- return "EndTag"
- case SelfClosingTagToken:
- return "SelfClosingTag"
- case CommentToken:
- return "Comment"
- case DoctypeToken:
- return "Doctype"
- }
- return "Invalid(" + strconv.Itoa(int(t)) + ")"
-}
-
-// An Attribute is an attribute namespace-key-value triple. Namespace is
-// non-empty for foreign attributes like xlink, Key is alphabetic (and hence
-// does not contain escapable characters like '&', '<' or '>'), and Val is
-// unescaped (it looks like "a<b" rather than "a&lt;b").
-//
-// Namespace is only used by the parser, not the tokenizer.
-type Attribute struct {
- Namespace, Key, Val string
-}
-
-// A Token consists of a TokenType and some Data (tag name for start and end
-// tags, content for text, comments and doctypes). A tag Token may also contain
-// a slice of Attributes. Data is unescaped for all Tokens (it looks like "a<b"
-// rather than "a&lt;b"). For tag Tokens, DataAtom is the atom for Data, or
-// zero if Data is not a known tag name.
-type Token struct {
- Type TokenType
- DataAtom atom.Atom
- Data string
- Attr []Attribute
-}
-
-// tagString returns a string representation of a tag Token's Data and Attr.
-func (t Token) tagString() string {
- if len(t.Attr) == 0 {
- return t.Data
- }
- buf := bytes.NewBufferString(t.Data)
- for _, a := range t.Attr {
- buf.WriteByte(' ')
- buf.WriteString(a.Key)
- buf.WriteString(`="`)
- escape(buf, a.Val)
- buf.WriteByte('"')
- }
- return buf.String()
-}
-
-// String returns a string representation of the Token.
-func (t Token) String() string {
- switch t.Type {
- case ErrorToken:
- return ""
- case TextToken:
- return EscapeString(t.Data)
- case StartTagToken:
- return "<" + t.tagString() + ">"
- case EndTagToken:
- return "</" + t.tagString() + ">"
- case SelfClosingTagToken:
- return "<" + t.tagString() + "/>"
- case CommentToken:
- return "<!--" + t.Data + "-->"
- case DoctypeToken:
- return "<!DOCTYPE " + t.Data + ">"
- }
- return "Invalid(" + strconv.Itoa(int(t.Type)) + ")"
-}
-
-// span is a range of bytes in a Tokenizer's buffer. The start is inclusive,
-// the end is exclusive.
-type span struct {
- start, end int
-}
-
-// A Tokenizer returns a stream of HTML Tokens.
-type Tokenizer struct {
- // r is the source of the HTML text.
- r io.Reader
- // tt is the TokenType of the current token.
- tt TokenType
- // err is the first error encountered during tokenization. It is possible
- // for tt != Error && err != nil to hold: this means that Next returned a
- // valid token but the subsequent Next call will return an error token.
- // For example, if the HTML text input was just "plain", then the first
- // Next call would set z.err to io.EOF but return a TextToken, and all
- // subsequent Next calls would return an ErrorToken.
- // err is never reset. Once it becomes non-nil, it stays non-nil.
- err error
- // buf[raw.start:raw.end] holds the raw bytes of the current token.
- // buf[raw.end:] is buffered input that will yield future tokens.
- raw span
- buf []byte
- // buf[data.start:data.end] holds the raw bytes of the current token's data:
- // a text token's text, a tag token's tag name, etc.
- data span
- // pendingAttr is the attribute key and value currently being tokenized.
- // When complete, pendingAttr is pushed onto attr. nAttrReturned is
- // incremented on each call to TagAttr.
- pendingAttr [2]span
- attr [][2]span
- nAttrReturned int
- // rawTag is the "script" in "</script>" that closes the next token. If
- // non-empty, the subsequent call to Next will return a raw or RCDATA text
- // token: one that treats "<p>" as text instead of an element.
- // rawTag's contents are lower-cased.
- rawTag string
- // textIsRaw is whether the current text token's data is not escaped.
- textIsRaw bool
- // convertNUL is whether NUL bytes in the current token's data should
- // be converted into \ufffd replacement characters.
- convertNUL bool
- // allowCDATA is whether CDATA sections are allowed in the current context.
- allowCDATA bool
-}
-
-// AllowCDATA sets whether or not the tokenizer recognizes <![CDATA[foo]]> as
-// the text "foo". The default value is false, which means to recognize it as
-// a bogus comment "<!-- [CDATA[foo]] -->" instead.
-//
-// Strictly speaking, an HTML5 compliant tokenizer should allow CDATA if and
-// only if tokenizing foreign content, such as MathML and SVG. However,
-// tracking foreign-contentness is difficult to do purely in the tokenizer,
-// as opposed to the parser, due to HTML integration points: an <svg> element
-// can contain a <foreignObject> that is foreign-to-SVG but not foreign-to-
-// HTML. For strict compliance with the HTML5 tokenization algorithm, it is the
-// responsibility of the user of a tokenizer to call AllowCDATA as appropriate.
-// In practice, if using the tokenizer without caring whether MathML or SVG
-// CDATA is text or comments, such as tokenizing HTML to find all the anchor
-// text, it is acceptable to ignore this responsibility.
-func (z *Tokenizer) AllowCDATA(allowCDATA bool) {
- z.allowCDATA = allowCDATA
-}
-
-// NextIsNotRawText instructs the tokenizer that the next token should not be
-// considered as 'raw text'. Some elements, such as script and title elements,
-// normally require the next token after the opening tag to be 'raw text' that
-// has no child elements. For example, tokenizing "<title>a<b>c</b>d</title>"
-// yields a start tag token for "<title>", a text token for "a<b>c</b>d", and
-// an end tag token for "</title>". There are no distinct start tag or end tag
-// tokens for the "<b>" and "</b>".
-//
-// This tokenizer implementation will generally look for raw text at the right
-// times. Strictly speaking, an HTML5 compliant tokenizer should not look for
-// raw text if in foreign content: <title> generally needs raw text, but a
-// <title> inside an <svg> does not. Another example is that a <textarea>
-// generally needs raw text, but a <textarea> is not allowed as an immediate
-// child of a <select>; in normal parsing, a <textarea> implies </select>, but
-// one cannot close the implicit element when parsing a <select>'s InnerHTML.
-// Similarly to AllowCDATA, tracking the correct moment to override raw-text-
-// ness is difficult to do purely in the tokenizer, as opposed to the parser.
-// For strict compliance with the HTML5 tokenization algorithm, it is the
-// responsibility of the user of a tokenizer to call NextIsNotRawText as
-// appropriate. In practice, like AllowCDATA, it is acceptable to ignore this
-// responsibility for basic usage.
-//
-// Note that this 'raw text' concept is different from the one offered by the
-// Tokenizer.Raw method.
-func (z *Tokenizer) NextIsNotRawText() {
- z.rawTag = ""
-}
-
-// Err returns the error associated with the most recent ErrorToken token.
-// This is typically io.EOF, meaning the end of tokenization.
-func (z *Tokenizer) Err() error {
- if z.tt != ErrorToken {
- return nil
- }
- return z.err
-}
-
-// readByte returns the next byte from the input stream, doing a buffered read
-// from z.r into z.buf if necessary. z.buf[z.raw.start:z.raw.end] remains a contiguous byte
-// slice that holds all the bytes read so far for the current token.
-// It sets z.err if the underlying reader returns an error.
-// Pre-condition: z.err == nil.
-func (z *Tokenizer) readByte() byte {
- if z.raw.end >= len(z.buf) {
- // Our buffer is exhausted and we have to read from z.r.
- // We copy z.buf[z.raw.start:z.raw.end] to the beginning of z.buf. If the length
- // z.raw.end - z.raw.start is more than half the capacity of z.buf, then we
- // allocate a new buffer before the copy.
- c := cap(z.buf)
- d := z.raw.end - z.raw.start
- var buf1 []byte
- if 2*d > c {
- buf1 = make([]byte, d, 2*c)
- } else {
- buf1 = z.buf[:d]
- }
- copy(buf1, z.buf[z.raw.start:z.raw.end])
- if x := z.raw.start; x != 0 {
- // Adjust the data/attr spans to refer to the same contents after the copy.
- z.data.start -= x
- z.data.end -= x
- z.pendingAttr[0].start -= x
- z.pendingAttr[0].end -= x
- z.pendingAttr[1].start -= x
- z.pendingAttr[1].end -= x
- for i := range z.attr {
- z.attr[i][0].start -= x
- z.attr[i][0].end -= x
- z.attr[i][1].start -= x
- z.attr[i][1].end -= x
- }
- }
- z.raw.start, z.raw.end, z.buf = 0, d, buf1[:d]
- // Now that we have copied the live bytes to the start of the buffer,
- // we read from z.r into the remainder.
- n, err := z.r.Read(buf1[d:cap(buf1)])
- if err != nil {
- z.err = err
- return 0
- }
- z.buf = buf1[:d+n]
- }
- x := z.buf[z.raw.end]
- z.raw.end++
- return x
-}
-
-// skipWhiteSpace skips past any white space.
-func (z *Tokenizer) skipWhiteSpace() {
- if z.err != nil {
- return
- }
- for {
- c := z.readByte()
- if z.err != nil {
- return
- }
- switch c {
- case ' ', '\n', '\r', '\t', '\f':
- // No-op.
- default:
- z.raw.end--
- return
- }
- }
-}
-
-// readRawOrRCDATA reads until the next "</foo>", where "foo" is z.rawTag and
-// is typically something like "script" or "textarea".
-func (z *Tokenizer) readRawOrRCDATA() {
- if z.rawTag == "script" {
- z.readScript()
- z.textIsRaw = true
- z.rawTag = ""
- return
- }
-loop:
- for {
- c := z.readByte()
- if z.err != nil {
- break loop
- }
- if c != '<' {
- continue loop
- }
- c = z.readByte()
- if z.err != nil {
- break loop
- }
- if c != '/' {
- continue loop
- }
- if z.readRawEndTag() || z.err != nil {
- break loop
- }
- }
- z.data.end = z.raw.end
- // A textarea's or title's RCDATA can contain escaped entities.
- z.textIsRaw = z.rawTag != "textarea" && z.rawTag != "title"
- z.rawTag = ""
-}
-
-// readRawEndTag attempts to read a tag like "</foo>", where "foo" is z.rawTag.
-// If it succeeds, it backs up the input position to reconsume the tag and
-// returns true. Otherwise it returns false. The opening "</" has already been
-// consumed.
-func (z *Tokenizer) readRawEndTag() bool {
- for i := 0; i < len(z.rawTag); i++ {
- c := z.readByte()
- if z.err != nil {
- return false
- }
- if c != z.rawTag[i] && c != z.rawTag[i]-('a'-'A') {
- z.raw.end--
- return false
- }
- }
- c := z.readByte()
- if z.err != nil {
- return false
- }
- switch c {
- case ' ', '\n', '\r', '\t', '\f', '/', '>':
- // The 3 is 2 for the leading "</" plus 1 for the trailing character c.
- z.raw.end -= 3 + len(z.rawTag)
- return true
- }
- z.raw.end--
- return false
-}
-
-// readScript reads until the next </script> tag, following the byzantine
-// rules for escaping/hiding the closing tag.
-func (z *Tokenizer) readScript() {
- defer func() {
- z.data.end = z.raw.end
- }()
- var c byte
-
-scriptData:
- c = z.readByte()
- if z.err != nil {
- return
- }
- if c == '<' {
- goto scriptDataLessThanSign
- }
- goto scriptData
-
-scriptDataLessThanSign:
- c = z.readByte()
- if z.err != nil {
- return
- }
- switch c {
- case '/':
- goto scriptDataEndTagOpen
- case '!':
- goto scriptDataEscapeStart
- }
- z.raw.end--
- goto scriptData
-
-scriptDataEndTagOpen:
- if z.readRawEndTag() || z.err != nil {
- return
- }
- goto scriptData
-
-scriptDataEscapeStart:
- c = z.readByte()
- if z.err != nil {
- return
- }
- if c == '-' {
- goto scriptDataEscapeStartDash
- }
- z.raw.end--
- goto scriptData
-
-scriptDataEscapeStartDash:
- c = z.readByte()
- if z.err != nil {
- return
- }
- if c == '-' {
- goto scriptDataEscapedDashDash
- }
- z.raw.end--
- goto scriptData
-
-scriptDataEscaped:
- c = z.readByte()
- if z.err != nil {
- return
- }
- switch c {
- case '-':
- goto scriptDataEscapedDash
- case '<':
- goto scriptDataEscapedLessThanSign
- }
- goto scriptDataEscaped
-
-scriptDataEscapedDash:
- c = z.readByte()
- if z.err != nil {
- return
- }
- switch c {
- case '-':
- goto scriptDataEscapedDashDash
- case '<':
- goto scriptDataEscapedLessThanSign
- }
- goto scriptDataEscaped
-
-scriptDataEscapedDashDash:
- c = z.readByte()
- if z.err != nil {
- return
- }
- switch c {
- case '-':
- goto scriptDataEscapedDashDash
- case '<':
- goto scriptDataEscapedLessThanSign
- case '>':
- goto scriptData
- }
- goto scriptDataEscaped
-
-scriptDataEscapedLessThanSign:
- c = z.readByte()
- if z.err != nil {
- return
- }
- if c == '/' {
- goto scriptDataEscapedEndTagOpen
- }
- if 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z' {
- goto scriptDataDoubleEscapeStart
- }
- z.raw.end--
- goto scriptData
-
-scriptDataEscapedEndTagOpen:
- if z.readRawEndTag() || z.err != nil {
- return
- }
- goto scriptDataEscaped
-
-scriptDataDoubleEscapeStart:
- z.raw.end--
- for i := 0; i < len("script"); i++ {
- c = z.readByte()
- if z.err != nil {
- return
- }
- if c != "script"[i] && c != "SCRIPT"[i] {
- z.raw.end--
- goto scriptDataEscaped
- }
- }
- c = z.readByte()
- if z.err != nil {
- return
- }
- switch c {
- case ' ', '\n', '\r', '\t', '\f', '/', '>':
- goto scriptDataDoubleEscaped
- }
- z.raw.end--
- goto scriptDataEscaped
-
-scriptDataDoubleEscaped:
- c = z.readByte()
- if z.err != nil {
- return
- }
- switch c {
- case '-':
- goto scriptDataDoubleEscapedDash
- case '<':
- goto scriptDataDoubleEscapedLessThanSign
- }
- goto scriptDataDoubleEscaped
-
-scriptDataDoubleEscapedDash:
- c = z.readByte()
- if z.err != nil {
- return
- }
- switch c {
- case '-':
- goto scriptDataDoubleEscapedDashDash
- case '<':
- goto scriptDataDoubleEscapedLessThanSign
- }
- goto scriptDataDoubleEscaped
-
-scriptDataDoubleEscapedDashDash:
- c = z.readByte()
- if z.err != nil {
- return
- }
- switch c {
- case '-':
- goto scriptDataDoubleEscapedDashDash
- case '<':
- goto scriptDataDoubleEscapedLessThanSign
- case '>':
- goto scriptData
- }
- goto scriptDataDoubleEscaped
-
-scriptDataDoubleEscapedLessThanSign:
- c = z.readByte()
- if z.err != nil {
- return
- }
- if c == '/' {
- goto scriptDataDoubleEscapeEnd
- }
- z.raw.end--
- goto scriptDataDoubleEscaped
-
-scriptDataDoubleEscapeEnd:
- if z.readRawEndTag() {
- z.raw.end += len("</script>")
- goto scriptDataEscaped
- }
- if z.err != nil {
- return
- }
- goto scriptDataDoubleEscaped
-}
-
-// readComment reads the next comment token starting with "<!--". The opening
-// "<!--" has already been consumed.
-func (z *Tokenizer) readComment() {
- z.data.start = z.raw.end
- defer func() {
- if z.data.end < z.data.start {
- // It's a comment with no data, like <!-->.
- z.data.end = z.data.start
- }
- }()
- for dashCount := 2; ; {
- c := z.readByte()
- if z.err != nil {
- // Ignore up to two dashes at EOF.
- if dashCount > 2 {
- dashCount = 2
- }
- z.data.end = z.raw.end - dashCount
- return
- }
- switch c {
- case '-':
- dashCount++
- continue
- case '>':
- if dashCount >= 2 {
- z.data.end = z.raw.end - len("-->")
- return
- }
- case '!':
- if dashCount >= 2 {
- c = z.readByte()
- if z.err != nil {
- z.data.end = z.raw.end
- return
- }
- if c == '>' {
- z.data.end = z.raw.end - len("--!>")
- return
- }
- }
- }
- dashCount = 0
- }
-}
-
-// readUntilCloseAngle reads until the next ">".
-func (z *Tokenizer) readUntilCloseAngle() {
- z.data.start = z.raw.end
- for {
- c := z.readByte()
- if z.err != nil {
- z.data.end = z.raw.end
- return
- }
- if c == '>' {
- z.data.end = z.raw.end - len(">")
- return
- }
- }
-}
-
-// readMarkupDeclaration reads the next token starting with "<!". It might be
-// a "<!--comment-->", a "<!DOCTYPE foo>", a "<![CDATA[section]]>" or
-// "<!a bogus comment". The opening "<!" has already been consumed.
-func (z *Tokenizer) readMarkupDeclaration() TokenType {
- z.data.start = z.raw.end
- var c [2]byte
- for i := 0; i < 2; i++ {
- c[i] = z.readByte()
- if z.err != nil {
- z.data.end = z.raw.end
- return CommentToken
- }
- }
- if c[0] == '-' && c[1] == '-' {
- z.readComment()
- return CommentToken
- }
- z.raw.end -= 2
- if z.readDoctype() {
- return DoctypeToken
- }
- if z.allowCDATA && z.readCDATA() {
- z.convertNUL = true
- return TextToken
- }
- // It's a bogus comment.
- z.readUntilCloseAngle()
- return CommentToken
-}
-
-// readDoctype attempts to read a doctype declaration and returns true if
-// successful. The opening "<!" has already been consumed.
-func (z *Tokenizer) readDoctype() bool {
- const s = "DOCTYPE"
- for i := 0; i < len(s); i++ {
- c := z.readByte()
- if z.err != nil {
- z.data.end = z.raw.end
- return false
- }
- if c != s[i] && c != s[i]+('a'-'A') {
- // Back up to read the fragment of "DOCTYPE" again.
- z.raw.end = z.data.start
- return false
- }
- }
- if z.skipWhiteSpace(); z.err != nil {
- z.data.start = z.raw.end
- z.data.end = z.raw.end
- return true
- }
- z.readUntilCloseAngle()
- return true
-}
-
-// readCDATA attempts to read a CDATA section and returns true if
-// successful. The opening "<!" has already been consumed.
-func (z *Tokenizer) readCDATA() bool {
- const s = "[CDATA["
- for i := 0; i < len(s); i++ {
- c := z.readByte()
- if z.err != nil {
- z.data.end = z.raw.end
- return false
- }
- if c != s[i] {
- // Back up to read the fragment of "[CDATA[" again.
- z.raw.end = z.data.start
- return false
- }
- }
- z.data.start = z.raw.end
- brackets := 0
- for {
- c := z.readByte()
- if z.err != nil {
- z.data.end = z.raw.end
- return true
- }
- switch c {
- case ']':
- brackets++
- case '>':
- if brackets >= 2 {
- z.data.end = z.raw.end - len("]]>")
- return true
- }
- brackets = 0
- default:
- brackets = 0
- }
- }
- panic("unreachable")
-}
-
-// startTagIn returns whether the start tag in z.buf[z.data.start:z.data.end]
-// case-insensitively matches any element of ss.
-func (z *Tokenizer) startTagIn(ss ...string) bool {
-loop:
- for _, s := range ss {
- if z.data.end-z.data.start != len(s) {
- continue loop
- }
- for i := 0; i < len(s); i++ {
- c := z.buf[z.data.start+i]
- if 'A' <= c && c <= 'Z' {
- c += 'a' - 'A'
- }
- if c != s[i] {
- continue loop
- }
- }
- return true
- }
- return false
-}
-
-// readStartTag reads the next start tag token. The opening "<a" has already
-// been consumed, where 'a' means anything in [A-Za-z].
-func (z *Tokenizer) readStartTag() TokenType {
- z.readTag(true)
- if z.err != nil {
- return ErrorToken
- }
- // Several tags flag the tokenizer's next token as raw.
- c, raw := z.buf[z.data.start], false
- if 'A' <= c && c <= 'Z' {
- c += 'a' - 'A'
- }
- switch c {
- case 'i':
- raw = z.startTagIn("iframe")
- case 'n':
- raw = z.startTagIn("noembed", "noframes", "noscript")
- case 'p':
- raw = z.startTagIn("plaintext")
- case 's':
- raw = z.startTagIn("script", "style")
- case 't':
- raw = z.startTagIn("textarea", "title")
- case 'x':
- raw = z.startTagIn("xmp")
- }
- if raw {
- z.rawTag = strings.ToLower(string(z.buf[z.data.start:z.data.end]))
- }
- // Look for a self-closing token like "<br/>".
- if z.err == nil && z.buf[z.raw.end-2] == '/' {
- return SelfClosingTagToken
- }
- return StartTagToken
-}
-
-// readTag reads the next tag token and its attributes. If saveAttr, those
-// attributes are saved in z.attr, otherwise z.attr is set to an empty slice.
-// The opening "<a" or "</a" has already been consumed, where 'a' means anything
-// in [A-Za-z].
-func (z *Tokenizer) readTag(saveAttr bool) {
- z.attr = z.attr[:0]
- z.nAttrReturned = 0
- // Read the tag name and attribute key/value pairs.
- z.readTagName()
- if z.skipWhiteSpace(); z.err != nil {
- return
- }
- for {
- c := z.readByte()
- if z.err != nil || c == '>' {
- break
- }
- z.raw.end--
- z.readTagAttrKey()
- z.readTagAttrVal()
- // Save pendingAttr if saveAttr and that attribute has a non-empty key.
- if saveAttr && z.pendingAttr[0].start != z.pendingAttr[0].end {
- z.attr = append(z.attr, z.pendingAttr)
- }
- if z.skipWhiteSpace(); z.err != nil {
- break
- }
- }
-}
-
-// readTagName sets z.data to the "div" in "<div k=v>". The reader (z.raw.end)
-// is positioned such that the first byte of the tag name (the "d" in "<div")
-// has already been consumed.
-func (z *Tokenizer) readTagName() {
- z.data.start = z.raw.end - 1
- for {
- c := z.readByte()
- if z.err != nil {
- z.data.end = z.raw.end
- return
- }
- switch c {
- case ' ', '\n', '\r', '\t', '\f':
- z.data.end = z.raw.end - 1
- return
- case '/', '>':
- z.raw.end--
- z.data.end = z.raw.end
- return
- }
- }
-}
-
-// readTagAttrKey sets z.pendingAttr[0] to the "k" in "<div k=v>".
-// Precondition: z.err == nil.
-func (z *Tokenizer) readTagAttrKey() {
- z.pendingAttr[0].start = z.raw.end
- for {
- c := z.readByte()
- if z.err != nil {
- z.pendingAttr[0].end = z.raw.end
- return
- }
- switch c {
- case ' ', '\n', '\r', '\t', '\f', '/':
- z.pendingAttr[0].end = z.raw.end - 1
- return
- case '=', '>':
- z.raw.end--
- z.pendingAttr[0].end = z.raw.end
- return
- }
- }
-}
-
-// readTagAttrVal sets z.pendingAttr[1] to the "v" in "<div k=v>".
-func (z *Tokenizer) readTagAttrVal() {
- z.pendingAttr[1].start = z.raw.end
- z.pendingAttr[1].end = z.raw.end
- if z.skipWhiteSpace(); z.err != nil {
- return
- }
- c := z.readByte()
- if z.err != nil {
- return
- }
- if c != '=' {
- z.raw.end--
- return
- }
- if z.skipWhiteSpace(); z.err != nil {
- return
- }
- quote := z.readByte()
- if z.err != nil {
- return
- }
- switch quote {
- case '>':
- z.raw.end--
- return
-
- case '\'', '"':
- z.pendingAttr[1].start = z.raw.end
- for {
- c := z.readByte()
- if z.err != nil {
- z.pendingAttr[1].end = z.raw.end
- return
- }
- if c == quote {
- z.pendingAttr[1].end = z.raw.end - 1
- return
- }
- }
-
- default:
- z.pendingAttr[1].start = z.raw.end - 1
- for {
- c := z.readByte()
- if z.err != nil {
- z.pendingAttr[1].end = z.raw.end
- return
- }
- switch c {
- case ' ', '\n', '\r', '\t', '\f':
- z.pendingAttr[1].end = z.raw.end - 1
- return
- case '>':
- z.raw.end--
- z.pendingAttr[1].end = z.raw.end
- return
- }
- }
- }
-}
-
-// Next scans the next token and returns its type.
-func (z *Tokenizer) Next() TokenType {
- if z.err != nil {
- z.tt = ErrorToken
- return z.tt
- }
- z.raw.start = z.raw.end
- z.data.start = z.raw.end
- z.data.end = z.raw.end
- if z.rawTag != "" {
- if z.rawTag == "plaintext" {
- // Read everything up to EOF.
- for z.err == nil {
- z.readByte()
- }
- z.data.end = z.raw.end
- z.textIsRaw = true
- } else {
- z.readRawOrRCDATA()
- }
- if z.data.end > z.data.start {
- z.tt = TextToken
- z.convertNUL = true
- return z.tt
- }
- }
- z.textIsRaw = false
- z.convertNUL = false
-
-loop:
- for {
- c := z.readByte()
- if z.err != nil {
- break loop
- }
- if c != '<' {
- continue loop
- }
-
- // Check if the '<' we have just read is part of a tag, comment
- // or doctype. If not, it's part of the accumulated text token.
- c = z.readByte()
- if z.err != nil {
- break loop
- }
- var tokenType TokenType
- switch {
- case 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z':
- tokenType = StartTagToken
- case c == '/':
- tokenType = EndTagToken
- case c == '!' || c == '?':
- // We use CommentToken to mean any of "<!--actual comments-->",
- // "<!DOCTYPE declarations>" and "<?xml processing instructions?>".
- tokenType = CommentToken
- default:
- continue
- }
-
- // We have a non-text token, but we might have accumulated some text
- // before that. If so, we return the text first, and return the non-
- // text token on the subsequent call to Next.
- if x := z.raw.end - len("<a"); z.raw.start < x {
- z.raw.end = x
- z.data.end = x
- z.tt = TextToken
- return z.tt
- }
- switch tokenType {
- case StartTagToken:
- z.tt = z.readStartTag()
- return z.tt
- case EndTagToken:
- c = z.readByte()
- if z.err != nil {
- break loop
- }
- if c == '>' {
- // "</>" does not generate a token at all.
- // Reset the tokenizer state and start again.
- z.raw.start = z.raw.end
- z.data.start = z.raw.end
- z.data.end = z.raw.end
- continue loop
- }
- if 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z' {
- z.readTag(false)
- if z.err != nil {
- z.tt = ErrorToken
- } else {
- z.tt = EndTagToken
- }
- return z.tt
- }
- z.raw.end--
- z.readUntilCloseAngle()
- z.tt = CommentToken
- return z.tt
- case CommentToken:
- if c == '!' {
- z.tt = z.readMarkupDeclaration()
- return z.tt
- }
- z.raw.end--
- z.readUntilCloseAngle()
- z.tt = CommentToken
- return z.tt
- }
- }
- if z.raw.start < z.raw.end {
- z.data.end = z.raw.end
- z.tt = TextToken
- return z.tt
- }
- z.tt = ErrorToken
- return z.tt
-}
-
-// Raw returns the unmodified text of the current token. Calling Next, Token,
-// Text, TagName or TagAttr may change the contents of the returned slice.
-func (z *Tokenizer) Raw() []byte {
- return z.buf[z.raw.start:z.raw.end]
-}
-
-// convertNewlines converts "\r" and "\r\n" in s to "\n".
-// The conversion happens in place, but the resulting slice may be shorter.
-func convertNewlines(s []byte) []byte {
- for i, c := range s {
- if c != '\r' {
- continue
- }
-
- src := i + 1
- if src >= len(s) || s[src] != '\n' {
- s[i] = '\n'
- continue
- }
-
- dst := i
- for src < len(s) {
- if s[src] == '\r' {
- if src+1 < len(s) && s[src+1] == '\n' {
- src++
- }
- s[dst] = '\n'
- } else {
- s[dst] = s[src]
- }
- src++
- dst++
- }
- return s[:dst]
- }
- return s
-}
-
-var (
- nul = []byte("\x00")
- replacement = []byte("\ufffd")
-)
-
-// Text returns the unescaped text of a text, comment or doctype token. The
-// contents of the returned slice may change on the next call to Next.
-func (z *Tokenizer) Text() []byte {
- switch z.tt {
- case TextToken, CommentToken, DoctypeToken:
- s := z.buf[z.data.start:z.data.end]
- z.data.start = z.raw.end
- z.data.end = z.raw.end
- s = convertNewlines(s)
- if (z.convertNUL || z.tt == CommentToken) && bytes.Contains(s, nul) {
- s = bytes.Replace(s, nul, replacement, -1)
- }
- if !z.textIsRaw {
- s = unescape(s, false)
- }
- return s
- }
- return nil
-}
-
-// TagName returns the lower-cased name of a tag token (the `img` out of
-// `<IMG SRC="foo">`) and whether the tag has attributes.
-// The contents of the returned slice may change on the next call to Next.
-func (z *Tokenizer) TagName() (name []byte, hasAttr bool) {
- if z.data.start < z.data.end {
- switch z.tt {
- case StartTagToken, EndTagToken, SelfClosingTagToken:
- s := z.buf[z.data.start:z.data.end]
- z.data.start = z.raw.end
- z.data.end = z.raw.end
- return lower(s), z.nAttrReturned < len(z.attr)
- }
- }
- return nil, false
-}
-
-// TagAttr returns the lower-cased key and unescaped value of the next unparsed
-// attribute for the current tag token and whether there are more attributes.
-// The contents of the returned slices may change on the next call to Next.
-func (z *Tokenizer) TagAttr() (key, val []byte, moreAttr bool) {
- if z.nAttrReturned < len(z.attr) {
- switch z.tt {
- case StartTagToken, SelfClosingTagToken:
- x := z.attr[z.nAttrReturned]
- z.nAttrReturned++
- key = z.buf[x[0].start:x[0].end]
- val = z.buf[x[1].start:x[1].end]
- return lower(key), unescape(convertNewlines(val), true), z.nAttrReturned < len(z.attr)
- }
- }
- return nil, nil, false
-}
-
-// Token returns the next Token. The result's Data and Attr values remain valid
-// after subsequent Next calls.
-func (z *Tokenizer) Token() Token {
- t := Token{Type: z.tt}
- switch z.tt {
- case TextToken, CommentToken, DoctypeToken:
- t.Data = string(z.Text())
- case StartTagToken, SelfClosingTagToken, EndTagToken:
- name, moreAttr := z.TagName()
- for moreAttr {
- var key, val []byte
- key, val, moreAttr = z.TagAttr()
- t.Attr = append(t.Attr, Attribute{"", atom.String(key), string(val)})
- }
- if a := atom.Lookup(name); a != 0 {
- t.DataAtom, t.Data = a, a.String()
- } else {
- t.DataAtom, t.Data = 0, string(name)
- }
- }
- return t
-}
-
-// NewTokenizer returns a new HTML Tokenizer for the given Reader.
-// The input is assumed to be UTF-8 encoded.
-func NewTokenizer(r io.Reader) *Tokenizer {
- return NewTokenizerFragment(r, "")
-}
-
-// NewTokenizerFragment returns a new HTML Tokenizer for the given Reader, for
-// tokenizing an exisitng element's InnerHTML fragment. contextTag is that
-// element's tag, such as "div" or "iframe".
-//
-// For example, how the InnerHTML "a<b" is tokenized depends on whether it is
-// for a <p> tag or a <script> tag.
-//
-// The input is assumed to be UTF-8 encoded.
-func NewTokenizerFragment(r io.Reader, contextTag string) *Tokenizer {
- z := &Tokenizer{
- r: r,
- buf: make([]byte, 0, 4096),
- }
- if contextTag != "" {
- switch s := strings.ToLower(contextTag); s {
- case "iframe", "noembed", "noframes", "noscript", "plaintext", "script", "style", "title", "textarea", "xmp":
- z.rawTag = s
- }
- }
- return z
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-25 06:49:21 +0000