# File lib/feed_tools/vendor/html5/lib/html5/sniffer.rb, line 4
 4:   def html_or_feed str
 5:     s = str[0, 512] # steps 1, 2
 6:     pos = 0
 7: 
 8:     while pos < s.length
 9:       case s[pos]
10:       when 0x09, 0x20, 0x0A, 0x0D # tab, space, LF, CR
11:         pos += 1
12:       when  0x3C # "<"
13:         pos += 1
14:         if s[pos..pos+2] == "!--" # [0x21, 0x2D, 0x2D]
15:           pos += 3
16:           until s[pos..pos+2] == "-->" or pos >= s.length
17:             pos += 1
18:           end
19:           pos += 3
20:         elsif s[pos] == 0x21 # "!"
21:           pos += 1
22:           until s[pos] == 0x3E or pos >= s.length # ">"
23:             pos += 1 
24:           end
25:           pos += 1
26:         elsif s[pos] == 0x3F # "?"
27:           until s[pos..pos+1] == "?>" or pos >= s.length # [0x3F, 0x3E]
28:             pos +=  1
29:           end
30:           pos += 2
31:         elsif s[pos..pos+2] == "rss"   # [0x72, 0x73, 0x73]
32:           return "application/rss+xml"
33:         elsif s[pos..pos+3] == "feed"  # [0x66, 0x65, 0x65, 0x64]
34:           return "application/atom+xml"
35:         elsif s[pos..pos+6] == "rdf:RDF" # [0x72, 0x64, 0x66, 0x3A, 0x52, 0x44, 0x46]
36:           raise NotImplementedError
37:         end
38:       else
39:         break
40:       end
41:     end
42:     "text/html"
43:   end