BEGIN {
use Exporter ();
use vars qw ($VERSION @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS);
- $VERSION = 0.07;
+ $VERSION = 0.08;
@ISA = qw (Exporter);
#Give a hoot don't pollute, do not export more than needed by default
@EXPORT = qw ();
=head1 DESCRIPTION
This module will read ISIS databases created by DOS CDS/ISIS, WinIsis or
-IsisMarc. It can be used as perl-only alternative to OpenIsis module.
+IsisMarc. It can be used as perl-only alternative to OpenIsis module which
+seems to depriciate it's old C<XS> bindings for perl.
It can create hash values from data in ISIS database (using C<to_hash>),
ASCII dump (using C<to_ascii>) or just hash with field names and packed
It also has support for identifiers (only if ISIS database is created by
IsisMarc), see C<to_hash>.
-This will module will always be slower than OpenIsis module which use C
+This module will always be slower than OpenIsis module which use C
library. However, since it's written in perl, it's platform independent (so
you don't need C compiler), and can be easily modified. I hope that it
creates data structures which are easier to use than ones created by
=head2 read_cnt
-This function is not really used by module, but can be useful to find info
-about your index (if debugging it for example).
+Read content of C<.CNT> file and return hash containing it.
print Dumper($isis->read_cnt);
+This function is not used by module (C<.CNT> files are not required for this
+module to work), but it can be useful to examine your index (while debugging
+for example).
+
=cut
sub read_cnt {
# is mfn allready in memory?
my $old_mfn = $self->{'current_mfn'} || -1;
- return if ($mfn == $old_mfn);
+ return $self->{record} if ($mfn == $old_mfn);
print STDERR "## fetch: $mfn\n" if ($self->{debug});
my $buff;
+ # delete old record
+ delete $self->{record};
+
# read XRFMFB abd XRFMFP
read($self->{'fileXRF'}, $buff, 4);
my $pointer=unpack("l",$buff) || carp "pointer is null";
+ # check for logically deleted record
+ if ($pointer < 0) {
+ print STDERR "## record $mfn is logically deleted\n" if ($self->{debug});
+ $self->{deleted} = $mfn;
+
+ return unless $self->{include_deleted};
+
+ $pointer = abs($pointer);
+ }
+
my $XRFMFB = int($pointer/2048);
my $XRFMFP = $pointer - ($XRFMFB*2048);
-
# (XRFMFB - 1) * 512 + XRFMFP
# why do i have to do XRFMFP % 1024 ?
- my $blk_off = (($XRFMFB - 1) * 512) + ($XRFMFP % 1024);
+ my $blk_off = (($XRFMFB - 1) * 512) + ($XRFMFP % 512);
print STDERR "## pointer: $pointer XRFMFB: $XRFMFB XRFMFP: $XRFMFP offset: $blk_off\n" if ($self->{'debug'});
print STDERR "## offset for rowid $value is $blk_off (blk $XRFMFB off $XRFMFP)\n" if ($self->{debug});
if ($value!=$mfn) {
- carp "Error: MFN ".$mfn." not found in MST(".$value.")";
- #return; # XXX deleted record?
- }
+ if ($value == 0) {
+ print STDERR "## record $mfn is physically deleted\n" if ($self->{debug});
+ $self->{deleted} = $mfn;
+ return;
+ }
-# $MFRL=$self->Read16($fileMST);
-# $MFBWB=$self->Read32($fileMST);
-# $MFBWP=$self->Read16($fileMST);
-# $BASE=$self->Read16($fileMST);
-# $NVF=$self->Read16($fileMST);
-# $STATUS=$self->Read16($fileMST);
+ carp "Error: MFN ".$mfn." not found in MST file, found $value";
+ return;
+ }
read($self->{'fileMST'}, $buff, 14);
print STDERR "## MFRL: $MFRL MFBWB: $MFBWB MFBWP: $MFBWP BASE: $BASE NVF: $NVF STATUS: $STATUS\n" if ($self->{debug});
- # delete old record
- delete $self->{record};
-
- ## FIXME this is a bug
- if (! $self->{'include_deleted'} && $MFRL < 0) {
- print "## logically deleted record $mfn, skipping...\n" if ($self->{debug});
- return;
- }
+ warn "MFRL $MFRL is not even number" unless ($MFRL % 2 == 0);
warn "BASE is not 18+6*NVF" unless ($BASE == 18 + 6 * $NVF);
for (my $i = 0 ; $i < $NVF ; $i++) {
-# $TAG=$self->Read16($fileMST);
-# $POS=$self->Read16($fileMST);
-# $LEN=$self->Read16($fileMST);
-
my ($TAG,$POS,$LEN) = unpack("sss", substr($buff,$i * 6, 6));
print STDERR "## TAG: $TAG POS: $POS LEN: $LEN\n" if ($self->{debug});
$self->{'current_mfn'} = $mfn;
- print Dumper($self),"\n" if ($self->{debug});
+ print STDERR Dumper($self),"\n" if ($self->{debug});
return $self->{'record'};
}
=head2 to_ascii
-Dump ASCII output of record with specified MFN
+Returns ASCII output of record with specified MFN
print $isis->to_ascii(42);
-It outputs something like this:
+This outputs something like this:
210 ^aNew York^cNew York University press^dcop. 1988
990 2140
my $hash = $isis->to_hash($mfn);
-It has ability to convert characters (using C<hash_filter> from ISIS
+It has ability to convert characters (using C<hash_filter>) from ISIS
database before creating structures enabling character re-mapping or quick
fix-up of data.
my $val;
# has identifiers?
- ($val->{'i1'},$val->{'i2'}) = ($1,$2) if ($l =~ s/^([01 #])([01 #])//);
+ ($val->{'i1'},$val->{'i2'}) = ($1,$2) if ($l =~ s/^([01 #])([01 #])\^/\^/);
# has subfields?
if ($l =~ m/\^/) {
=head1 BUGS
-This module has been very lightly tested. Use with caution and report bugs.
+Some parts of CDS/ISIS documentation are not detailed enough to exmplain
+some variations in input databases which has been tested with this module.
+When I was in doubt, I assumed that OpenIsis's implementation was right
+(except for obvious bugs).
+
+However, every effort has been made to test this module with as much
+databases (and programs that create them) as possible.
+
+I would be very greatful for success or failure reports about usage of this
+module with databases from programs other than WinIsis and IsisMarc. I had
+tested this against ouput of one C<isis.dll>-based application, but I don't
+know any details about it's version.
=head1 AUTHOR
projects / Biblio-Isis / blobdiff