2 # The User/Sysop Filter module
4 # The way this works is that the filter routine is actually
5 # a predefined function that returns 0 if it is OK and 1 if it
6 # is not when presented with a list of things.
8 # This set of routines provide a means of maintaining the filter
9 # scripts which are compiled in when an entity connects.
11 # Copyright (c) 1999 Dirk Koopman G1TLH
17 # The filters live in a directory tree of their own in $main::root/filter
19 # Each type of filter (e.g. spot, wwv) live in a tree of their own so you
20 # can have different filters for different things for the same callsign.
22 # Each filter file has the same structure:-
26 # [ action, fieldno, fieldsort, comparison ],
30 # The action is usually 1 or 0 but could be any numeric value
32 # The fieldno is the field no in the list of fields that is presented
35 # The fieldsort is the type of field that we are dealing with which
36 # currently can be 'a', 'n', 'r' or 'd'. 'a' is alphanumeric, 'n' is
37 # numeric, 'r' is ranges of pairs of numeric values and 'd' is default.
39 # Filter::it basically goes thru the list of comparisons from top to
40 # bottom and when one matches it will return the action. The fields
41 # are the element nos of the list that is presented to Filter::it. Element
42 # 0 is the first field of the list.
54 use vars qw ($filterbasefn);
56 $filterbasefn = "$main::root/filter";
58 # initial filter system
65 # takes the reference to the filter (the first argument) and applies
66 # it to the subsequent arguments and returns the action specified.
76 for $ref (@{$filter}) {
77 my ($action, $field, $fieldsort, $comp) = @{$ref};
78 if ($fieldsort eq 'n') {
80 return $action if grep $_ == $val, @{$comp};
81 } elsif ($fieldsort eq 'r') {
85 for ($i = 0; $i < @range; $i += 2) {
86 return $action if $val >= $range[$i] && $val <= $range[$i+1];
88 } elsif ($fieldsort eq 'a') {
89 return $action if $_[$field] =~ m{$comp};
91 return $action; # the default action
96 # this reads in a filter statement and returns it as a list
98 # The filter is stored in straight perl so that it can be parsed and read
99 # in with a 'do' statement. The 'do' statement reads the filter into
100 # @in which is a list of references
104 my ($sort, $call) = @_;
105 my $fn = "$filterbasefn/$sort/$call.pl";
115 # this writes out the filter in a form suitable to be read in by 'read_in'
116 # It expects a list of references to filter lines
121 my $fn = "$filterbasefn/$sort";
124 # make the output directory
125 mkdir $fn, 0777 unless -e $fn;
128 $fn = "$fn/$call.pl";
129 unless (open FILTER, ">$fn") {
130 warn "can't open $fn $!" ;
134 my $today = localtime;
136 # Filter for $call stored $today
143 my ($action, $field, $fieldsort, $comp) = @{$ref};
144 print FILTER "\t[ $action, $field, $fieldsort,";
145 if ($fieldsort eq 'n' || $fieldsort eq 'r') {
146 print FILTER "[ ", join (',', $comp), " ],";
147 } elsif ($fieldsort eq 'a') {
151 print FILTER " ],\n";