Bug 18925: Fix null/empty behavior, again
[koha.git] / C4 / AuthoritiesMarc / MARC21.pm
blob8ebae705fe33a2ca3dc0e3941f0e189a9b0192e0
1 package C4::AuthoritiesMarc::MARC21;
3 # Copyright (C) 2007 LibLime
4 #
5 # This file is part of Koha.
7 # Koha is free software; you can redistribute it and/or modify it
8 # under the terms of the GNU General Public License as published by
9 # the Free Software Foundation; either version 3 of the License, or
10 # (at your option) any later version.
12 # Koha is distributed in the hope that it will be useful, but
13 # WITHOUT ANY WARRANTY; without even the implied warranty of
14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 # GNU General Public License for more details.
17 # You should have received a copy of the GNU General Public License
18 # along with Koha; if not, see <http://www.gnu.org/licenses>.
20 use strict;
21 #use warnings; FIXME - Bug 2505
22 use MARC::Record;
24 =head1 NAME
26 C4::AuthoritiesMarc::MARC21
28 =head1 SYNOPSIS
30 use C4::AuthoritiesMarc::MARC21;
32 =head1 DESCRIPTION
34 This is a helper module providing functions used by
35 C<C4::AuthoritiesMarc> to deal with behavior specific
36 to MARC21 authority records (as opposed to other
37 MARC formats).
39 Functions from this module generally should not be used
40 directly; instead, use the appropriate function from
41 C<C4::Authorities> that will dispatch the appropriate
42 function based on the marcflavour system preference.
44 =head1 FUNCTIONS
46 =cut
48 =head2 get_heading_type_from_marc
50 my $auth_type = get_auth_type_from_marc($marc);
52 Given a MARC::Record object containing an authority record,
53 determine its heading type (e.g., personal name, topical term,
54 etc.).
56 =cut
58 =head2 default_auth_type_location
60 my ($tag, $subfield) = default_auth_type_location();
62 Get the tag and subfield used to store the heading type
63 if not specified in the MARC framework. For MARC21,
64 this defaults to 942$a.
66 =cut
68 sub default_auth_type_location {
69 return ('942', 'a');
72 =head2 fix_marc21_auth_type_location
74 fix_marc21_auth_type_location($auth_marc, $auth_type_tag, $auth_type_subfield);
76 If the incoming C<MARC::Record> object has a 152$b, remove it. If no
77 field already exists that contains the specified C<$auth_type_tag>
78 and C<$auth_type_subfield>, create a new field whose contents
79 are the original contents of the 152$b.
81 This routine exists to deal with a historical problem: MARC21
82 authority records in previous versions of Koha kept the
83 authority type in the 152$b. While the 152 may be OK for UNIMARC,
84 a 9XX should have been used for MARC21.
86 This function is meant to be called from GetAuthority, GetAuthorityXML,
87 and AddAuthority.
89 FIXME: This function should be removed once it's determined
90 that no MARC21 users of Koha are using the 152$b
91 to store the authority type.
93 =cut
95 sub fix_marc21_auth_type_location {
96 my ($auth_marc, $auth_type_tag, $auth_type_subfield) = @_;
98 my $auth_type_code;
99 return unless $auth_type_code = $auth_marc->subfield('152', 'b');
100 $auth_marc->delete_field($auth_marc->field('152'));
101 unless ($auth_marc->field($auth_type_tag) && $auth_marc->subfield($auth_type_tag, $auth_type_subfield)) {
102 $auth_marc->add_fields($auth_type_tag,'','', $auth_type_subfield=>$auth_type_code);
107 =head1 AUTHOR
109 Koha Development Team <http://koha-community.org/>
111 Galen Charlton <galen.charlton@liblime.com>
113 =cut