| // 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 mime |
| |
| import ( |
| "strings" |
| ) |
| |
| // isTSpecial returns true if rune is in 'tspecials' as defined by RFC |
| // 1531 and RFC 2045. |
| func isTSpecial(rune int) bool { |
| return strings.IndexRune(`()<>@,;:\"/[]?=`, rune) != -1 |
| } |
| |
| // IsTokenChar returns true if rune is in 'token' as defined by RFC |
| // 1531 and RFC 2045. |
| func IsTokenChar(rune int) bool { |
| // token := 1*<any (US-ASCII) CHAR except SPACE, CTLs, |
| // or tspecials> |
| return rune > 0x20 && rune < 0x7f && !isTSpecial(rune) |
| } |
| |
| // IsQText returns true if rune is in 'qtext' as defined by RFC 822. |
| func IsQText(rune int) bool { |
| // CHAR = <any ASCII character> ; ( 0-177, 0.-127.) |
| // qtext = <any CHAR excepting <">, ; => may be folded |
| // "\" & CR, and including |
| // linear-white-space> |
| switch rune { |
| case '"', '\\', '\r': |
| return false |
| } |
| return rune < 0x80 |
| } |