README
¶
utf7 
RFC 2152 - UTF7 encoding and decoding.
Documentation
¶
Overview ¶
This package modified from: https://github.com/mxk/go-imap/blob/master/imap/utf7.go https://github.com/mxk/go-imap/blob/master/imap/utf7_test.go IMAP specification uses modified UTF-7. Following are the differences:
- Printable US-ASCII except & (0x20 to 0x25 and 0x27 to 0x7e) MUST represent by themselves.
- '&' is used to shift modified BASE64 instead of '+'.
- Can NOT use superfluous null shift (&...-&...- should be just &......-).
- ',' is used in BASE64 code instead of '/'.
- '&' is represented '&-'. You can have many '&-&-&-&-'.
- No implicit shift from BASE64 to US-ASCII. All BASE64 must end with '-'.
Actual UTF-7 specification: Rule 1: direct characters: 62 alphanumeric characters and 9 symbols: ' ( ) , - . / : ? Rule 2: optional direct characters: all other printable characters in the range U+0020–U+007E except ~ \ + and space. Plus sign (+) may be encoded as +- (special case). Plus sign (+) mean the start of 'modified Base64 encoded UTF-16'. The end of this block is indicated by any character not in the modified Base64. If character after modified Base64 is a '-' then it is consumed.
Example:
"1 + 1 = 2" is encoded as "1 +- 1 +AD0 2" //+AD0 is the '=' sign. "£1" is encoded as "+AKM-1" //+AKM- is the '£' sign where '-' is consumed.
A "+" character followed immediately by any character other than members of modified Base64 or "-" is an ill-formed sequence. Convert to Unicode code point then apply modified BASE64 (rfc2045) to it. Modified BASE64 do not use padding instead add extra bits. Lines should never be broken in the middle of a UTF-7 shifted sequence. Rule 3: Space, tab, carriage return and line feed may also be represented directly as single ASCII bytes. Further content transfer encoding may be needed if using in email environment.
Index ¶
Constants ¶
This section is empty.
Variables ¶
var ErrBadUTF7 = errors.New("utf7: bad utf-7 encoding")
ErrBadUTF7 is returned to indicate invalid modified UTF-7 encoding.
var (
UTF7 encoding.Encoding = &simpleEncoding{
utf7Decoder{},
utf7Encoder{},
}
)
Functions ¶
func UTF7Decode ¶
UTF7Decode converts a string from modified UTF-7 encoding to UTF-8.
func UTF7DecodeBytes ¶
UTF7DecodeBytes converts a byte slice from modified UTF-7 encoding to UTF-8.
func UTF7Encode ¶
UTF7Encode converts a string from UTF-8 encoding to modified UTF-7. This encoding is used by the Mailbox International Naming Convention (RFC 3501 section 5.1.3). Invalid UTF-8 byte sequences are replaced by the Unicode replacement code point (U+FFFD).
func UTF7EncodeBytes ¶
UTF7EncodeBytes converts a byte slice from UTF-8 encoding to modified UTF-7.
Types ¶
This section is empty.
Source Files