Imported Upstream version 60

1 files changed, 0 insertions, 509 deletions

diff --git a/src/pkg/html/token.go b/src/pkg/html/token.go
deleted file mode 100644
index 23c95ece6..000000000
--- a/src/pkg/html/token.go
+++ /dev/null
@@ -1,509 +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"
-	"io"
-	"os"
-	"strconv"
-)
-
-// A TokenType is the type of a Token.
-type TokenType int
-
-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
-)
-
-// 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"
-	}
-	return "Invalid(" + strconv.Itoa(int(t)) + ")"
-}
-
-// An Attribute is an attribute key-value pair. 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").
-type Attribute struct {
-	Key, Val string
-}
-
-// A Token consists of a TokenType and some Data (tag name for start and end
-// tags, content for text and comments). 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").
-type Token struct {
-	Type TokenType
-	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.NewBuffer(nil)
-	buf.WriteString(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 "<!--" + EscapeString(t.Data) + "-->"
-	}
-	return "Invalid(" + strconv.Itoa(int(t.Type)) + ")"
-}
-
-// A Tokenizer returns a stream of HTML Tokens.
-type Tokenizer struct {
-	// If ReturnComments is set, Next returns comment tokens;
-	// otherwise it skips over comments (default).
-	ReturnComments bool
-
-	// r is the source of the HTML text.
-	r io.Reader
-	// tt is the TokenType of the most recently read token. If tt == Error
-	// then err is the error associated with trying to read that token.
-	tt  TokenType
-	err os.Error
-	// buf[p0:p1] holds the raw data of the most recent token.
-	// buf[p1:] is buffered input that will yield future tokens.
-	p0, p1 int
-	buf    []byte
-}
-
-// Error returns the error associated with the most recent ErrorToken token.
-// This is typically os.EOF, meaning the end of tokenization.
-func (z *Tokenizer) Error() os.Error {
-	if z.tt != ErrorToken {
-		return nil
-	}
-	return z.err
-}
-
-// 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.p0:z.p1]
-}
-
-// readByte returns the next byte from the input stream, doing a buffered read
-// from z.r into z.buf if necessary. z.buf[z.p0:z.p1] remains a contiguous byte
-// slice that holds all the bytes read so far for the current token.
-func (z *Tokenizer) readByte() (byte, os.Error) {
-	if z.p1 >= len(z.buf) {
-		// Our buffer is exhausted and we have to read from z.r.
-		// We copy z.buf[z.p0:z.p1] to the beginning of z.buf. If the length
-		// z.p1 - z.p0 is more than half the capacity of z.buf, then we
-		// allocate a new buffer before the copy.
-		c := cap(z.buf)
-		d := z.p1 - z.p0
-		var buf1 []byte
-		if 2*d > c {
-			buf1 = make([]byte, d, 2*c)
-		} else {
-			buf1 = z.buf[0:d]
-		}
-		copy(buf1, z.buf[z.p0:z.p1])
-		z.p0, z.p1, z.buf = 0, d, buf1[0: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 {
-			return 0, err
-		}
-		z.buf = buf1[0 : d+n]
-	}
-	x := z.buf[z.p1]
-	z.p1++
-	return x, nil
-}
-
-// readTo keeps reading bytes until x is found.
-func (z *Tokenizer) readTo(x uint8) os.Error {
-	for {
-		c, err := z.readByte()
-		if err != nil {
-			return err
-		}
-		switch c {
-		case x:
-			return nil
-		case '\\':
-			_, err = z.readByte()
-			if err != nil {
-				return err
-			}
-		}
-	}
-	panic("unreachable")
-}
-
-// nextMarkupDeclaration returns the next TokenType starting with "<!".
-func (z *Tokenizer) nextMarkupDeclaration() (TokenType, os.Error) {
-	// TODO: check for <!DOCTYPE ... >, don't just assume that it's a comment.
-	for i := 0; i < 2; i++ {
-		c, err := z.readByte()
-		if err != nil {
-			return TextToken, err
-		}
-		if c != '-' {
-			return z.nextText(), nil
-		}
-	}
-	// <!--> is a valid comment.
-	for dashCount := 2; ; {
-		c, err := z.readByte()
-		if err != nil {
-			return TextToken, err
-		}
-		switch c {
-		case '-':
-			dashCount++
-		case '>':
-			if dashCount >= 2 {
-				return CommentToken, nil
-			}
-			fallthrough
-		default:
-			dashCount = 0
-		}
-	}
-	panic("unreachable")
-}
-
-// nextTag returns the next TokenType starting from the tag open state.
-func (z *Tokenizer) nextTag() (tt TokenType, err os.Error) {
-	c, err := z.readByte()
-	if err != nil {
-		return ErrorToken, err
-	}
-	switch {
-	case c == '/':
-		tt = EndTagToken
-	// Lower-cased characters are more common in tag names, so we check for them first.
-	case 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z':
-		tt = StartTagToken
-	case c == '!':
-		return z.nextMarkupDeclaration()
-	case c == '?':
-		return ErrorToken, os.NewError("html: TODO(nigeltao): implement XML processing instructions")
-	default:
-		return ErrorToken, os.NewError("html: TODO(nigeltao): handle malformed tags")
-	}
-	for {
-		c, err := z.readByte()
-		if err != nil {
-			return TextToken, err
-		}
-		switch c {
-		case '"':
-			err = z.readTo('"')
-			if err != nil {
-				return TextToken, err
-			}
-		case '\'':
-			err = z.readTo('\'')
-			if err != nil {
-				return TextToken, err
-			}
-		case '>':
-			if z.buf[z.p1-2] == '/' && tt == StartTagToken {
-				return SelfClosingTagToken, nil
-			}
-			return tt, nil
-		}
-	}
-	panic("unreachable")
-}
-
-// nextText reads all text up until an '<'.
-func (z *Tokenizer) nextText() TokenType {
-	for {
-		c, err := z.readByte()
-		if err != nil {
-			z.tt, z.err = ErrorToken, err
-			if err == os.EOF {
-				z.tt = TextToken
-			}
-			return z.tt
-		}
-		if c == '<' {
-			z.p1--
-			z.tt = TextToken
-			return z.tt
-		}
-	}
-	panic("unreachable")
-}
-
-// Next scans the next token and returns its type.
-func (z *Tokenizer) Next() TokenType {
-	for {
-		if z.err != nil {
-			z.tt = ErrorToken
-			return z.tt
-		}
-		z.p0 = z.p1
-		c, err := z.readByte()
-		if err != nil {
-			z.tt, z.err = ErrorToken, err
-			return z.tt
-		}
-		if c == '<' {
-			z.tt, z.err = z.nextTag()
-			if z.tt == CommentToken && !z.ReturnComments {
-				continue
-			}
-			return z.tt
-		}
-		return z.nextText()
-	}
-	panic("unreachable")
-}
-
-// trim returns the largest j such that z.buf[i:j] contains only white space,
-// or only white space plus the final ">" or "/>" of the raw data.
-func (z *Tokenizer) trim(i int) int {
-	k := z.p1
-	for ; i < k; i++ {
-		switch z.buf[i] {
-		case ' ', '\n', '\t', '\f':
-			continue
-		case '>':
-			if i == k-1 {
-				return k
-			}
-		case '/':
-			if i == k-2 {
-				return k
-			}
-		}
-		return i
-	}
-	return k
-}
-
-// word finds the largest alphabetic [0-9A-Za-z]* word at the start
-// of z.buf[i:] and returns that word (optionally lower-cased), as
-// well as the trimmed cursor location after that word.
-func (z *Tokenizer) word(i int, lower bool) ([]byte, int) {
-	i0 := i
-loop:
-	for ; i < z.p1; i++ {
-		c := z.buf[i]
-		switch {
-		case '0' <= c && c <= '9':
-			// No-op.
-		case 'A' <= c && c <= 'Z':
-			if lower {
-				z.buf[i] = c + 'a' - 'A'
-			}
-		case 'a' <= c && c <= 'z':
-			// No-op.
-		default:
-			break loop
-		}
-	}
-	return z.buf[i0:i], z.trim(i)
-}
-
-// attrName finds the largest attribute name at the start
-// of z.buf[i:] and returns it lower-cased, as well
-// as the trimmed cursor location after that word.
-//
-// http://dev.w3.org/html5/spec/Overview.html#syntax-attribute-name
-// TODO: unicode characters
-func (z *Tokenizer) attrName(i int) ([]byte, int) {
-	i0 := i
-loop:
-	for ; i < z.p1; i++ {
-		c := z.buf[i]
-		switch c {
-		case '<', '>', '"', '\'', '/', '=':
-			break loop
-		}
-		switch {
-		case 'A' <= c && c <= 'Z':
-			z.buf[i] = c + 'a' - 'A'
-		case c > ' ' && c < 0x7f:
-			// No-op.
-		default:
-			break loop
-		}
-	}
-	return z.buf[i0:i], z.trim(i)
-}
-
-// Text returns the unescaped text of a TextToken or a CommentToken.
-// The contents of the returned slice may change on the next call to Next.
-func (z *Tokenizer) Text() []byte {
-	switch z.tt {
-	case TextToken:
-		s := unescape(z.Raw())
-		z.p0 = z.p1
-		return s
-	case CommentToken:
-		// We trim the "<!--" from the left and the "-->" from the right.
-		// "<!-->" is a valid comment, so the adjusted endpoints might overlap.
-		i0 := z.p0 + 4
-		i1 := z.p1 - 3
-		z.p0 = z.p1
-		var s []byte
-		if i0 < i1 {
-			s = unescape(z.buf[i0:i1])
-		}
-		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) {
-	i := z.p0 + 1
-	if i >= z.p1 {
-		z.p0 = z.p1
-		return nil, false
-	}
-	if z.buf[i] == '/' {
-		i++
-	}
-	name, z.p0 = z.word(i, true)
-	hasAttr = z.p0 != z.p1
-	return
-}
-
-// 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) {
-	key, i := z.attrName(z.p0)
-	// Check for an empty attribute value.
-	if i == z.p1 {
-		z.p0 = i
-		return
-	}
-	// Get past the equals and quote characters.
-	if z.buf[i] != '=' {
-		z.p0, moreAttr = i, true
-		return
-	}
-	i = z.trim(i + 1)
-	if i == z.p1 {
-		z.p0 = i
-		return
-	}
-	closeQuote := z.buf[i]
-	if closeQuote != '\'' && closeQuote != '"' {
-		val, z.p0 = z.word(i, false)
-		moreAttr = z.p0 != z.p1
-		return
-	}
-	i = z.trim(i + 1)
-	// Copy and unescape everything up to the closing quote.
-	dst, src := i, i
-loop:
-	for src < z.p1 {
-		c := z.buf[src]
-		switch c {
-		case closeQuote:
-			src++
-			break loop
-		case '&':
-			dst, src = unescapeEntity(z.buf, dst, src)
-		case '\\':
-			if src == z.p1 {
-				z.buf[dst] = '\\'
-				dst++
-			} else {
-				z.buf[dst] = z.buf[src+1]
-				dst, src = dst+1, src+2
-			}
-		default:
-			z.buf[dst] = c
-			dst, src = dst+1, src+1
-		}
-	}
-	val, z.p0 = z.buf[i:dst], z.trim(src)
-	moreAttr = z.p0 != z.p1
-	return
-}
-
-// 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:
-		t.Data = string(z.Text())
-	case StartTagToken, EndTagToken, SelfClosingTagToken:
-		var attr []Attribute
-		name, moreAttr := z.TagName()
-		for moreAttr {
-			var key, val []byte
-			key, val, moreAttr = z.TagAttr()
-			attr = append(attr, Attribute{string(key), string(val)})
-		}
-		t.Data = string(name)
-		t.Attr = attr
-	}
-	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 &Tokenizer{
-		r:   r,
-		buf: make([]byte, 0, 4096),
-	}
-}