Hello,

libpcre3 is known to be very fast, not sure you will notice any performance impact because of runtime regular expression parsing, everything being done in memory and for sure not with simple expressions like "(?i)^test$". This happens because the parameters can have variables, which are first evaluated, then used for matching.

Anyhow, a variant of the function with static parameter for regex can be added easily.

On the other hand, you seem to compare with a full value, so you can just use string comparison functions:

  * https://www.kamailio.org/docs/modules/stable/modules/textops.html#textops.f.cmp_str

Cheers,
Daniel

Henning, Daniel,

thanks for your replies.

1. I don't want to use a Regex module because it might have a performance impact.

Matches the given string parameter against the regular expression pcre_regex, which is compiled in runtime into a PCRE object.

 

2.  I was surprised to find that the operator "=~" is case insensitive:

if (regcomp(re, (char*) exp->r.param,

REG_EXTENDED|REG_NOSUB|REG_ICASE) ){

LM_CRIT("bad re \"%s\"\n", (char*) exp->r.param);

pkg_free(re);

return E_BAD_RE;

}

so that enough for me:

$tU =~ "^test$"

Btw, what if I need case sensitive validation? Should I use the Regex module?

Regards,

Marat

вт, 13 окт. 2020 г. в 14:17, Daniel-Constantin Mierla <miconda@gmail.com>:

Hello,

adding some more details to mention that regex operations done by the core (the =~ operator) use the libc posix regex functions, which do not support extended syntax. Also, these operations done by core use the case insensitive flag.

As mentioned by Henning, regex should be an alternative, or maybe dialplan if one wants db-storage+caching of those regex rules.

Moreover, if the above are not enough, a kemi embedded interpreter (e.g., app_lua, app_python) can be used with inline execution in kamailio.cfg routing blocks -- those external scripting languages should have many options for regex matching.

Cheers,
Daniel

On 13.10.20 13:04, Henning Westerholt wrote:

Hello,

 

just an idea, have you already tried this module: https://www.kamailio.org/docs/modules/stable/modules/regex.html

 

Cheers,

 

Henning

 

--

Henning Westerholt – https://skalatan.de/blog/

Kamailio services – https://gilawa.com

 

From: sr-users <sr-users-bounces@lists.kamailio.org> On Behalf Of Marat Gareev
Sent: Tuesday, October 13, 2020 10:55 AM
To: Kamailio (SER) - Users Mailing List <sr-users@lists.kamailio.org>
Subject: [SR-Users] Caseless regex

 

Hello,

 

Is it possible write more readable regular expression

if ($tU =~ "(?i)^test$") {

    ...

}

instead of "^[tT][eE][sS][tT]$"?

 

On the first option, I get the error:

0(47250) ERROR: <core> [core/rvalue.c:3038]: fix_match_rve(): Bad regular expression

 

Regards,

Marat

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-- 
Daniel-Constantin Mierla -- www.asipto.com
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_______________________________________________
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sr-users@lists.kamailio.org
https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users

-- 
Daniel-Constantin Mierla -- www.asipto.com
www.twitter.com/miconda -- www.linkedin.com/in/miconda
Funding: https://www.paypal.me/dcmierla