C#

RFC5424[^]

SD-IDs are case-sensitive and uniquely identify the type and purpose
of the SD-ELEMENT. The same SD-ID MUST NOT exist more than once in a
message.

There are two formats for SD-ID names:

o Names that do not contain an at-sign ("@", ABNF %d64) are reserved
to be assigned by IETF Review as described in BCP26 [RFC5226].
Currently, these are the names defined in Section 7. Names of
this format are only valid if they are first registered with the
IANA. Registered names MUST NOT contain an at-sign ('@', ABNF
%d64), an equal-sign ('=', ABNF %d61), a closing brace (']', ABNF
%d93), a quote-character ('"', ABNF %d34), whitespace, or control
characters (ASCII code 127 and codes 32 or less).

o Anyone can define additional SD-IDs using names in the format
name@<private enterprise="" number="">, e.g., "ourSDID@32473". The
format of the part preceding the at-sign is not specified;
however, these names MUST be printable US-ASCII strings, and MUST
NOT contain an at-sign ('@', ABNF %d64), an equal-sign ('=', ABNF
%d61), a closing brace (']', ABNF %d93), a quote-character ('"',
ABNF %d34), whitespace, or control characters. The part following
the at-sign MUST be a private enterprise number as specified in
Section 7.2.2. Please note that throughout this document the
value of 32473 is used for all private enterprise numbers. This
value has been reserved by IANA to be used as an example number in
documentation. Implementors will need to use their own private
enterprise number for the enterpriseId parameter, and when
creating locally extensible SD-ID names.

([!-~][^@=\]\"])+@(\d)+(\.(\d)+)*

Kornfeld Eliyahu Peter wrote:

char except control chars (0-31), white-space (32),

Kornfeld Eliyahu Peter wrote:

@, =, " and ].

Kornfeld Eliyahu Peter wrote:

After that must come a @ (one and only one!).

Kornfeld Eliyahu Peter wrote:

The last part is made of digits optionally separated by . (dot)...

Marco Bertschi wrote:

true, but your regex only allows ! and ~

Marco Bertschi wrote:

They must be escaped, e.g. @ as \@.

Kornfeld Eliyahu Peter wrote:

According to RFC they are can't take part - no mentioning of escapes!

Quote:

Inside PARAM-VALUE, the characters '"' (ABNF %d34), '\' (ABNF %d92),
and ']' (ABNF %d93) MUST be escaped. This is necessary to avoid
parsing errors. Escaping ']' would not strictly be necessary but is
REQUIRED by this specification to avoid syslog application
implementation errors. Each of these three characters MUST be
escaped as '\"', '\\', and '\]' respectively. The backslash is used
for control character escaping for consistency with its use for
escaping in other parts of the syslog message as well as in
traditional syslog.

A backslash ('\') followed by none of the three described characters
is considered an invalid escape sequence. In this case, the
backslash MUST be treated as a regular backslash and the following
character as a regular character. Thus, the invalid sequence MUST
not be altered.

([!-~][^@=\]\"])+@(\d)+(\.(\d)+)*

([^"\]\\]|(\\")|(\\])|\\{2})*

Kornfeld Eliyahu Peter wrote:

It's not clearly stated (or I missed) but seems to me that SD-ID and PARAM-NAME should not exceed the length of 32 characters...

Marco Bertschi wrote:

This is true for SD-ID, but PARAM-NAME can be an UTF8 string of any length

RFC 5424:

SD-ID = SD-NAME
PARAM-NAME = SD-NAME

SD-NAME = 1*32PRINTUSASCII ; except '=', SP, ']', %d34 (")

Marco Bertschi wrote:

I will not check this using the Regex since I will be faster just checking for string.Length.

Marco Bertschi wrote:

I will publish my RFC5424 implementation as article on CodeProject

Kornfeld Eliyahu Peter wrote:

According to this SD-ID and PARAM-NAME are the same - SD-NAME, and SD-NAME has a maximum of 32...

Quote:

PARAM-VALUE = UTF-8-STRING ; characters '"', '\' and
; ']' MUST be escaped.

Kornfeld Eliyahu Peter wrote:

It must have to be an excellent quality - otherwise I will not let it pass moderation!

Kornfeld Eliyahu Peter wrote:

SD-PARAM is build from PARAM-NAME and PARAM-VALUE. PARAM-NAME is the same as SD-ID...

PARAM-VALUE build like

* any UTF-8

* the characters ", \ and ] must be escaped (by \)

The regex for that is -

([^"\]\\]|(\\")|(\\])|\\{2})*

(?<!\\)@|(?<!\\)\[|(?<!\\)\]|(?<!\\)"

(?<!match)

Marco Bertschi wrote:

my clever book