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Diffstat (limited to 'vendor/golang.org/x/net/html/charset/charset.go')
-rw-r--r--vendor/golang.org/x/net/html/charset/charset.go257
1 files changed, 0 insertions, 257 deletions
diff --git a/vendor/golang.org/x/net/html/charset/charset.go b/vendor/golang.org/x/net/html/charset/charset.go
deleted file mode 100644
index 13bed15..0000000
--- a/vendor/golang.org/x/net/html/charset/charset.go
+++ /dev/null
@@ -1,257 +0,0 @@
-// Copyright 2013 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 charset provides common text encodings for HTML documents.
-//
-// The mapping from encoding labels to encodings is defined at
-// https://encoding.spec.whatwg.org/.
-package charset // import "golang.org/x/net/html/charset"
-
-import (
- "bytes"
- "fmt"
- "io"
- "mime"
- "strings"
- "unicode/utf8"
-
- "golang.org/x/net/html"
- "golang.org/x/text/encoding"
- "golang.org/x/text/encoding/charmap"
- "golang.org/x/text/encoding/htmlindex"
- "golang.org/x/text/transform"
-)
-
-// Lookup returns the encoding with the specified label, and its canonical
-// name. It returns nil and the empty string if label is not one of the
-// standard encodings for HTML. Matching is case-insensitive and ignores
-// leading and trailing whitespace. Encoders will use HTML escape sequences for
-// runes that are not supported by the character set.
-func Lookup(label string) (e encoding.Encoding, name string) {
- e, err := htmlindex.Get(label)
- if err != nil {
- return nil, ""
- }
- name, _ = htmlindex.Name(e)
- return &htmlEncoding{e}, name
-}
-
-type htmlEncoding struct{ encoding.Encoding }
-
-func (h *htmlEncoding) NewEncoder() *encoding.Encoder {
- // HTML requires a non-terminating legacy encoder. We use HTML escapes to
- // substitute unsupported code points.
- return encoding.HTMLEscapeUnsupported(h.Encoding.NewEncoder())
-}
-
-// DetermineEncoding determines the encoding of an HTML document by examining
-// up to the first 1024 bytes of content and the declared Content-Type.
-//
-// See http://www.whatwg.org/specs/web-apps/current-work/multipage/parsing.html#determining-the-character-encoding
-func DetermineEncoding(content []byte, contentType string) (e encoding.Encoding, name string, certain bool) {
- if len(content) > 1024 {
- content = content[:1024]
- }
-
- for _, b := range boms {
- if bytes.HasPrefix(content, b.bom) {
- e, name = Lookup(b.enc)
- return e, name, true
- }
- }
-
- if _, params, err := mime.ParseMediaType(contentType); err == nil {
- if cs, ok := params["charset"]; ok {
- if e, name = Lookup(cs); e != nil {
- return e, name, true
- }
- }
- }
-
- if len(content) > 0 {
- e, name = prescan(content)
- if e != nil {
- return e, name, false
- }
- }
-
- // Try to detect UTF-8.
- // First eliminate any partial rune at the end.
- for i := len(content) - 1; i >= 0 && i > len(content)-4; i-- {
- b := content[i]
- if b < 0x80 {
- break
- }
- if utf8.RuneStart(b) {
- content = content[:i]
- break
- }
- }
- hasHighBit := false
- for _, c := range content {
- if c >= 0x80 {
- hasHighBit = true
- break
- }
- }
- if hasHighBit && utf8.Valid(content) {
- return encoding.Nop, "utf-8", false
- }
-
- // TODO: change default depending on user's locale?
- return charmap.Windows1252, "windows-1252", false
-}
-
-// NewReader returns an io.Reader that converts the content of r to UTF-8.
-// It calls DetermineEncoding to find out what r's encoding is.
-func NewReader(r io.Reader, contentType string) (io.Reader, error) {
- preview := make([]byte, 1024)
- n, err := io.ReadFull(r, preview)
- switch {
- case err == io.ErrUnexpectedEOF:
- preview = preview[:n]
- r = bytes.NewReader(preview)
- case err != nil:
- return nil, err
- default:
- r = io.MultiReader(bytes.NewReader(preview), r)
- }
-
- if e, _, _ := DetermineEncoding(preview, contentType); e != encoding.Nop {
- r = transform.NewReader(r, e.NewDecoder())
- }
- return r, nil
-}
-
-// NewReaderLabel returns a reader that converts from the specified charset to
-// UTF-8. It uses Lookup to find the encoding that corresponds to label, and
-// returns an error if Lookup returns nil. It is suitable for use as
-// encoding/xml.Decoder's CharsetReader function.
-func NewReaderLabel(label string, input io.Reader) (io.Reader, error) {
- e, _ := Lookup(label)
- if e == nil {
- return nil, fmt.Errorf("unsupported charset: %q", label)
- }
- return transform.NewReader(input, e.NewDecoder()), nil
-}
-
-func prescan(content []byte) (e encoding.Encoding, name string) {
- z := html.NewTokenizer(bytes.NewReader(content))
- for {
- switch z.Next() {
- case html.ErrorToken:
- return nil, ""
-
- case html.StartTagToken, html.SelfClosingTagToken:
- tagName, hasAttr := z.TagName()
- if !bytes.Equal(tagName, []byte("meta")) {
- continue
- }
- attrList := make(map[string]bool)
- gotPragma := false
-
- const (
- dontKnow = iota
- doNeedPragma
- doNotNeedPragma
- )
- needPragma := dontKnow
-
- name = ""
- e = nil
- for hasAttr {
- var key, val []byte
- key, val, hasAttr = z.TagAttr()
- ks := string(key)
- if attrList[ks] {
- continue
- }
- attrList[ks] = true
- for i, c := range val {
- if 'A' <= c && c <= 'Z' {
- val[i] = c + 0x20
- }
- }
-
- switch ks {
- case "http-equiv":
- if bytes.Equal(val, []byte("content-type")) {
- gotPragma = true
- }
-
- case "content":
- if e == nil {
- name = fromMetaElement(string(val))
- if name != "" {
- e, name = Lookup(name)
- if e != nil {
- needPragma = doNeedPragma
- }
- }
- }
-
- case "charset":
- e, name = Lookup(string(val))
- needPragma = doNotNeedPragma
- }
- }
-
- if needPragma == dontKnow || needPragma == doNeedPragma && !gotPragma {
- continue
- }
-
- if strings.HasPrefix(name, "utf-16") {
- name = "utf-8"
- e = encoding.Nop
- }
-
- if e != nil {
- return e, name
- }
- }
- }
-}
-
-func fromMetaElement(s string) string {
- for s != "" {
- csLoc := strings.Index(s, "charset")
- if csLoc == -1 {
- return ""
- }
- s = s[csLoc+len("charset"):]
- s = strings.TrimLeft(s, " \t\n\f\r")
- if !strings.HasPrefix(s, "=") {
- continue
- }
- s = s[1:]
- s = strings.TrimLeft(s, " \t\n\f\r")
- if s == "" {
- return ""
- }
- if q := s[0]; q == '"' || q == '\'' {
- s = s[1:]
- closeQuote := strings.IndexRune(s, rune(q))
- if closeQuote == -1 {
- return ""
- }
- return s[:closeQuote]
- }
-
- end := strings.IndexAny(s, "; \t\n\f\r")
- if end == -1 {
- end = len(s)
- }
- return s[:end]
- }
- return ""
-}
-
-var boms = []struct {
- bom []byte
- enc string
-}{
- {[]byte{0xfe, 0xff}, "utf-16be"},
- {[]byte{0xff, 0xfe}, "utf-16le"},
- {[]byte{0xef, 0xbb, 0xbf}, "utf-8"},
-}