1 // Copyright 2009 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.
7 // This file deals with lexical matters of HTTP
9 func isSeparator(c byte) bool {
11 case '(', ')', '<', '>', '@', ',', ';', ':', '\\', '"', '/', '[', ']', '?', '=', '{', '}', ' ', '\t':
17 func isSpace(c byte) bool {
19 case ' ', '\t', '\r', '\n':
25 func isCtl(c byte) bool { return (0 <= c && c <= 31) || c == 127 }
27 func isChar(c byte) bool { return 0 <= c && c <= 127 }
29 func isAnyText(c byte) bool { return !isCtl(c) }
31 func isQdText(c byte) bool { return isAnyText(c) && c != '"' }
33 func isToken(c byte) bool { return isChar(c) && !isCtl(c) && !isSeparator(c) }
35 // Valid escaped sequences are not specified in RFC 2616, so for now, we assume
36 // that they coincide with the common sense ones used by GO. Malformed
37 // characters should probably not be treated as errors by a robust (forgiving)
38 // parser, so we replace them with the '?' character.
39 func httpUnquotePair(b byte) byte {
40 // skip the first byte, which should always be '\'
66 // raw must begin with a valid quoted string. Only the first quoted string is
67 // parsed and is unquoted in result. eaten is the number of bytes parsed, or -1
69 func httpUnquote(raw []byte) (eaten int, result string) {
70 buf := make([]byte, len(raw))
75 j := 0 // # of bytes written in buf
76 for i := 1; i < len(raw); i++ {
77 switch b := raw[i]; b {
81 return i + 1, string(buf)
86 buf[j] = httpUnquotePair(raw[i+1])
103 // This is a best effort parse, so errors are not returned, instead not all of
104 // the input string might be parsed. result is always non-nil.
105 func httpSplitFieldValue(fv string) (eaten int, result []string) {
106 result = make([]string, 0, len(fv))
114 eaten, unq := httpUnquote(raw[i:len(raw)])
123 result = result[0 : len(result)+1]
124 result[len(result)-1] = chunk
131 case b == '\n' || b == '\r':
139 result = result[0 : len(result)+1]
140 result[len(result)-1] = chunk