vendor/golang.org/x/net/html/doctype.go

   1 // Copyright 2011 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 package html
   6
   7 import (
   8         "strings"
   9 )
  10
  11 // parseDoctype parses the data from a DoctypeToken into a name,
  12 // public identifier, and system identifier. It returns a Node whose Type
  13 // is DoctypeNode, whose Data is the name, and which has attributes
  14 // named "system" and "public" for the two identifiers if they were present.
  15 // quirks is whether the document should be parsed in "quirks mode".
  16 func parseDoctype(s string) (n *Node, quirks bool) {
  17         n = &Node{Type: DoctypeNode}
  18
  19         // Find the name.
  20         space := strings.IndexAny(s, whitespace)
  21         if space == -1 {
  22                 space = len(s)
  23         }
  24         n.Data = s[:space]
  25         // The comparison to "html" is case-sensitive.
  26         if n.Data != "html" {
  27                 quirks = true
  28         }
  29         n.Data = strings.ToLower(n.Data)
  30         s = strings.TrimLeft(s[space:], whitespace)
  31
  32         if len(s) < 6 {
  33                 // It can't start with "PUBLIC" or "SYSTEM".
  34                 // Ignore the rest of the string.
  35                 return n, quirks || s != ""
  36         }
  37
  38         key := strings.ToLower(s[:6])
  39         s = s[6:]
  40         for key == "public" || key == "system" {
  41                 s = strings.TrimLeft(s, whitespace)
  42                 if s == "" {
  43                         break
  44                 }
  45                 quote := s[0]
  46                 if quote != '"' && quote != '\'' {
  47                         break
  48                 }
  49                 s = s[1:]
  50                 q := strings.IndexRune(s, rune(quote))
  51                 var id string
  52                 if q == -1 {
  53                         id = s
  54                         s = ""
  55                 } else {
  56                         id = s[:q]
  57                         s = s[q+1:]
  58                 }
  59                 n.Attr = append(n.Attr, Attribute{Key: key, Val: id})
  60                 if key == "public" {
  61                         key = "system"
  62                 } else {
  63                         key = ""
  64                 }
  65         }
  66
  67         if key != "" || s != "" {
  68                 quirks = true
  69         } else if len(n.Attr) > 0 {
  70                 if n.Attr[0].Key == "public" {
  71                         public := strings.ToLower(n.Attr[0].Val)
  72                         switch public {
  73                         case "-//w3o//dtd w3 html strict 3.0//en//", "-/w3d/dtd html 4.0 transitional/en", "html":
  74                                 quirks = true
  75                         default:
  76                                 for _, q := range quirkyIDs {
  77                                         if strings.HasPrefix(public, q) {
  78                                                 quirks = true
  79                                                 break
  80                                         }
  81                                 }
  82                         }
  83                         // The following two public IDs only cause quirks mode if there is no system ID.
  84                         if len(n.Attr) == 1 && (strings.HasPrefix(public, "-//w3c//dtd html 4.01 frameset//") ||
  85                                 strings.HasPrefix(public, "-//w3c//dtd html 4.01 transitional//")) {
  86                                 quirks = true
  87                         }
  88                 }
  89                 if lastAttr := n.Attr[len(n.Attr)-1]; lastAttr.Key == "system" &&
  90                         strings.ToLower(lastAttr.Val) == "http://www.ibm.com/data/dtd/v11/ibmxhtml1-transitional.dtd" {
  91                         quirks = true
  92                 }
  93         }
  94
  95         return n, quirks
  96 }
  97
  98 // quirkyIDs is a list of public doctype identifiers that cause a document
  99 // to be interpreted in quirks mode. The identifiers should be in lower case.
 100 var quirkyIDs = []string{
 101         "+//silmaril//dtd html pro v0r11 19970101//",
 102         "-//advasoft ltd//dtd html 3.0 aswedit + extensions//",
 103         "-//as//dtd html 3.0 aswedit + extensions//",
 104         "-//ietf//dtd html 2.0 level 1//",
 105         "-//ietf//dtd html 2.0 level 2//",
 106         "-//ietf//dtd html 2.0 strict level 1//",
 107         "-//ietf//dtd html 2.0 strict level 2//",
 108         "-//ietf//dtd html 2.0 strict//",
 109         "-//ietf//dtd html 2.0//",
 110         "-//ietf//dtd html 2.1e//",
 111         "-//ietf//dtd html 3.0//",
 112         "-//ietf//dtd html 3.2 final//",
 113         "-//ietf//dtd html 3.2//",
 114         "-//ietf//dtd html 3//",
 115         "-//ietf//dtd html level 0//",
 116         "-//ietf//dtd html level 1//",
 117         "-//ietf//dtd html level 2//",
 118         "-//ietf//dtd html level 3//",
 119         "-//ietf//dtd html strict level 0//",
 120         "-//ietf//dtd html strict level 1//",
 121         "-//ietf//dtd html strict level 2//",
 122         "-//ietf//dtd html strict level 3//",
 123         "-//ietf//dtd html strict//",
 124         "-//ietf//dtd html//",
 125         "-//metrius//dtd metrius presentational//",
 126         "-//microsoft//dtd internet explorer 2.0 html strict//",
 127         "-//microsoft//dtd internet explorer 2.0 html//",
 128         "-//microsoft//dtd internet explorer 2.0 tables//",
 129         "-//microsoft//dtd internet explorer 3.0 html strict//",
 130         "-//microsoft//dtd internet explorer 3.0 html//",
 131         "-//microsoft//dtd internet explorer 3.0 tables//",
 132         "-//netscape comm. corp.//dtd html//",
 133         "-//netscape comm. corp.//dtd strict html//",
 134         "-//o'reilly and associates//dtd html 2.0//",
 135         "-//o'reilly and associates//dtd html extended 1.0//",
 136         "-//o'reilly and associates//dtd html extended relaxed 1.0//",
 137         "-//softquad software//dtd hotmetal pro 6.0::19990601::extensions to html 4.0//",
 138         "-//softquad//dtd hotmetal pro 4.0::19971010::extensions to html 4.0//",
 139         "-//spyglass//dtd html 2.0 extended//",
 140         "-//sq//dtd html 2.0 hotmetal + extensions//",
 141         "-//sun microsystems corp.//dtd hotjava html//",
 142         "-//sun microsystems corp.//dtd hotjava strict html//",
 143         "-//w3c//dtd html 3 1995-03-24//",
 144         "-//w3c//dtd html 3.2 draft//",
 145         "-//w3c//dtd html 3.2 final//",
 146         "-//w3c//dtd html 3.2//",
 147         "-//w3c//dtd html 3.2s draft//",
 148         "-//w3c//dtd html 4.0 frameset//",
 149         "-//w3c//dtd html 4.0 transitional//",
 150         "-//w3c//dtd html experimental 19960712//",
 151         "-//w3c//dtd html experimental 970421//",
 152         "-//w3c//dtd w3 html//",
 153         "-//w3o//dtd w3 html 3.0//",
 154         "-//webtechs//dtd mozilla html 2.0//",
 155         "-//webtechs//dtd mozilla html//",
 156 }