Subroutines

Starting with ZXTM 5.0, TrafficScript^TM has gained the ability to create new subroutines to reduce code duplication inside a TrafficScript rule.

For example:

sub securityerror( $url )
{
    log.error( $url . " failed a security check from " .
                request.getremoteip() );
    http.sendresponse( "403 Permission denied", "text/html", 
                       "Permission Denied", "" );
}

if( request.getremoteip() == "1.2.3.4" ) {
   securityerror( http.getrawurl() );
} else if( string.startswith( http.getpath(), "/secure" ) ) {
   securityerror( http.getrawurl() );
}

Data can be returned from a subroutine using the 'return' statement, additionally $1 -> $9 are available as global variables.

When using subroutines there are some points to be aware of:

• Variables (except $1 -> $9) are local to the subroutine, so arguments should be used to pass data to a subroutine.
• The subroutine can be declared anywhere in the TrafficScript rule, there is no need to declare it before it is used.
• The number of arguments is always checked at compile time so calling subroutines will never cause a run time error.
• Subroutines can, of course, call other subroutines (or themselves!).

Crispin Flowerday [Zeus Dev Team] 13 June 2008