X-Git-Url: http://git.rot13.org/?p=Biblio-Isis;a=blobdiff_plain;f=lib%2FBiblio%2FIsis.pm;fp=lib%2FBiblio%2FIsis.pm;h=2690020a3388e0d18d9e8d721a577dc9a0500808;hp=0000000000000000000000000000000000000000;hb=93653871b2f53e6f93524bc5ee4f761bfd6f678f;hpb=07932c16ad44896d07f77d3e20b9df7dac7bc0ac diff --git a/lib/Biblio/Isis.pm b/lib/Biblio/Isis.pm new file mode 100644 index 0000000..2690020 --- /dev/null +++ b/lib/Biblio/Isis.pm @@ -0,0 +1,621 @@ +package Biblio::Isis; +use strict; + +use Carp; +use File::Glob qw(:globally :nocase); + +use Data::Dumper; + +BEGIN { + use Exporter (); + use vars qw ($VERSION @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS); + $VERSION = 0.11; + @ISA = qw (Exporter); + #Give a hoot don't pollute, do not export more than needed by default + @EXPORT = qw (); + @EXPORT_OK = qw (); + %EXPORT_TAGS = (); + +} + +=head1 NAME + +Biblio::Isis - Read CDS/ISIS, WinISIS and IsisMarc database + +=head1 SYNOPSIS + + use Biblio::Isis; + + my $isis = new Biblio::Isis( + isisdb => './cds/cds', + ); + + for(my $mfn = 1; $mfn <= $isis->count; $mfn++) { + print $isis->to_ascii($mfn),"\n"; + } + +=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 which +seems to depriciate it's old C bindings for perl. + +It can create hash values from data in ISIS database (using C), +ASCII dump (using C) or just hash with field names and packed +values (like C<^asomething^belse>). + +Unique feature of this module is ability to C records. +It will also skip zero sized fields (OpenIsis has a bug in XS bindings, so +fields which are zero sized will be filled with random junk from memory). + +It also has support for identifiers (only if ISIS database is created by +IsisMarc), see 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 +OpenIsis, so reduced time in other parts of the code should compensate for +slower performance of this module (speed of reading ISIS database is +rarely an issue). + +=head1 METHODS + +=cut + +# my $ORDN; # Nodes Order +# my $ORDF; # Leafs Order +# my $N; # Number of Memory buffers for nodes +# my $K; # Number of buffers for first level index +# my $LIV; # Current number of Index Levels +# my $POSRX; # Pointer to Root Record in N0x +# my $NMAXPOS; # Next Available position in N0x +# my $FMAXPOS; # Next available position in L0x +# my $ABNORMAL; # Formal BTree normality indicator + +# +# some binary reads +# + +=head2 new + +Open ISIS database + + my $isis = new Biblio::Isis( + isisdb => './cds/cds', + read_fdt => 1, + include_deleted => 1, + hash_filter => sub { + my $v = shift; + $v =~ s#foo#bar#g; + }, + debug => 1, + ); + +Options are described below: + +=over 5 + +=item isisdb + +This is full or relative path to ISIS database files which include +common prefix of C<.MST>, and C<.XRF> and optionally C<.FDT> (if using +C option) files. + +In this example it uses C<./cds/cds.MST> and related files. + +=item read_fdt + +Boolean flag to specify if field definition table should be read. It's off +by default. + +=item include_deleted + +Don't skip logically deleted records in ISIS. + +=item hash_filter + +Filter code ref which will be used before data is converted to hash. + +=item debug + +Dump a B of debugging output. + +=back + +=cut + +sub new { + my $class = shift; + my $self = {}; + bless($self, $class); + + croak "new needs database name (isisdb) as argument!" unless ({@_}->{isisdb}); + + foreach my $v (qw{isisdb debug include_deleted hash_filter}) { + $self->{$v} = {@_}->{$v}; + } + + my @isis_files = grep(/\.(FDT|MST|XRF|CNT)$/i,glob($self->{isisdb}."*")); + + foreach my $f (@isis_files) { + my $ext = $1 if ($f =~ m/\.(\w\w\w)$/); + $self->{lc($ext)."_file"} = $f; + } + + my @must_exist = qw(mst xrf); + push @must_exist, "fdt" if ($self->{read_fdt}); + + foreach my $ext (@must_exist) { + croak "missing ",uc($ext)," file in ",$self->{isisdb} unless ($self->{$ext."_file"}); + } + + print STDERR "## using files: ",join(" ",@isis_files),"\n" if ($self->{debug}); + + # if you want to read .FDT file use read_fdt argument when creating class! + if ($self->{read_fdt} && -e $self->{fdt_file}) { + + # read the $db.FDT file for tags + my $fieldzone=0; + + open(my $fileFDT, $self->{fdt_file}) || croak "can't read '$self->{fdt_file}': $!"; + binmode($fileFDT); + + while (<$fileFDT>) { + chomp; + if ($fieldzone) { + my $name=substr($_,0,30); + my $tag=substr($_,50,3); + + $name =~ s/\s+$//; + $tag =~ s/\s+$//; + + $self->{'TagName'}->{$tag}=$name; + } + + if (/^\*\*\*/) { + $fieldzone=1; + } + } + + close($fileFDT); + } + + # Get the Maximum MFN from $db.MST + + open($self->{'fileMST'}, $self->{mst_file}) || croak "can't open '$self->{mst_file}': $!"; + binmode($self->{'fileMST'}); + + # MST format: (* = 32 bit signed) + # CTLMFN* always 0 + # NXTMFN* MFN to be assigned to the next record created + # NXTMFB* last block allocated to master file + # NXTMFP offset to next available position in last block + # MFTYPE always 0 for user db file (1 for system) + seek($self->{'fileMST'},4,0) || croak "can't seek to offset 0 in MST: $!"; + + my $buff; + + read($self->{'fileMST'}, $buff, 4) || croak "can't read NXTMFN from MST: $!"; + $self->{'NXTMFN'}=unpack("V",$buff) || croak "NXTNFN is zero"; + + print STDERR Dumper($self),"\n" if ($self->{debug}); + + # open files for later + open($self->{'fileXRF'}, $self->{xrf_file}) || croak "can't open '$self->{xrf_file}': $!"; + binmode($self->{'fileXRF'}); + + $self ? return $self : return undef; +} + +=head2 count + +Return number of records in database + + print $isis->count; + +=cut + +sub count { + my $self = shift; + return $self->{'NXTMFN'} - 1; +} + +=head2 fetch + +Read record with selected MFN + + my $rec = $isis->fetch(55); + +Returns hash with keys which are field names and values are unpacked values +for that field like this: + + $rec = { + '210' => [ '^aNew York^cNew York University press^dcop. 1988' ], + '990' => [ '2140', '88', 'HAY' ], + }; + +=cut + +sub fetch { + my $self = shift; + + my $mfn = shift || croak "fetch needs MFN as argument!"; + + # is mfn allready in memory? + my $old_mfn = $self->{'current_mfn'} || -1; + return $self->{record} if ($mfn == $old_mfn); + + print STDERR "## fetch: $mfn\n" if ($self->{debug}); + + # XXX check this? + my $mfnpos=($mfn+int(($mfn-1)/127))*4; + + print STDERR "## seeking to $mfnpos in file '$self->{xrf_file}'\n" if ($self->{debug}); + seek($self->{'fileXRF'},$mfnpos,0); + + my $buff; + + # delete old record + delete $self->{record}; + + # read XRFMFB abd XRFMFP + read($self->{'fileXRF'}, $buff, 4); + my $pointer=unpack("V",$buff) || croak "pointer is null"; + + # check for logically deleted record + if ($pointer & 0x80000000) { + print STDERR "## record $mfn is logically deleted\n" if ($self->{debug}); + $self->{deleted} = $mfn; + + return unless $self->{include_deleted}; + + # abs + $pointer = ($pointer ^ 0xffffffff) + 1; + } + + 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 % 512); + + print STDERR "## pointer: $pointer XRFMFB: $XRFMFB XRFMFP: $XRFMFP offset: $blk_off\n" if ($self->{'debug'}); + + # Get Record Information + + seek($self->{'fileMST'},$blk_off,0) || croak "can't seek to $blk_off: $!"; + + read($self->{'fileMST'}, $buff, 4) || croak "can't read 4 bytes at offset $blk_off from MST file: $!"; + my $value=unpack("V",$buff); + + print STDERR "## offset for rowid $value is $blk_off (blk $XRFMFB off $XRFMFP)\n" if ($self->{debug}); + + if ($value!=$mfn) { + if ($value == 0) { + print STDERR "## record $mfn is physically deleted\n" if ($self->{debug}); + $self->{deleted} = $mfn; + return; + } + + carp "Error: MFN ".$mfn." not found in MST file, found $value"; + return; + } + + read($self->{'fileMST'}, $buff, 14); + + my ($MFRL,$MFBWB,$MFBWP,$BASE,$NVF,$STATUS) = unpack("vVvvvv", $buff); + + print STDERR "## MFRL: $MFRL MFBWB: $MFBWB MFBWP: $MFBWP BASE: $BASE NVF: $NVF STATUS: $STATUS\n" if ($self->{debug}); + + warn "MFRL $MFRL is not even number" unless ($MFRL % 2 == 0); + + warn "BASE is not 18+6*NVF" unless ($BASE == 18 + 6 * $NVF); + + # Get Directory Format + + my @FieldPOS; + my @FieldLEN; + my @FieldTAG; + + read($self->{'fileMST'}, $buff, 6 * $NVF); + + my $rec_len = 0; + + for (my $i = 0 ; $i < $NVF ; $i++) { + + my ($TAG,$POS,$LEN) = unpack("vvv", substr($buff,$i * 6, 6)); + + print STDERR "## TAG: $TAG POS: $POS LEN: $LEN\n" if ($self->{debug}); + + # The TAG does not exists in .FDT so we set it to 0. + # + # XXX This is removed from perl version; .FDT file is updated manually, so + # you will often have fields in .MST file which aren't in .FDT. On the other + # hand, IsisMarc doesn't use .FDT files at all! + + #if (! $self->{TagName}->{$TAG}) { + # $TAG=0; + #} + + push @FieldTAG,$TAG; + push @FieldPOS,$POS; + push @FieldLEN,$LEN; + + $rec_len += $LEN; + } + + # Get Variable Fields + + read($self->{'fileMST'},$buff,$rec_len); + + print STDERR "## rec_len: $rec_len poc: ",tell($self->{'fileMST'})."\n" if ($self->{debug}); + + for (my $i = 0 ; $i < $NVF ; $i++) { + # skip zero-sized fields + next if ($FieldLEN[$i] == 0); + + push @{$self->{record}->{$FieldTAG[$i]}}, substr($buff,$FieldPOS[$i],$FieldLEN[$i]); + } + + $self->{'current_mfn'} = $mfn; + + print STDERR Dumper($self),"\n" if ($self->{debug}); + + return $self->{'record'}; +} + +=head2 to_ascii + +Returns ASCII output of record with specified MFN + + print $isis->to_ascii(42); + +This outputs something like this: + + 210 ^aNew York^cNew York University press^dcop. 1988 + 990 2140 + 990 88 + 990 HAY + +If C is specified when calling C it will display field names +from C<.FDT> file instead of numeric tags. + +=cut + +sub to_ascii { + my $self = shift; + + my $mfn = shift || croak "need MFN"; + + my $rec = $self->fetch($mfn); + + my $out = "0\t$mfn"; + + foreach my $f (sort keys %{$rec}) { + my $fn = $self->tag_name($f); + $out .= "\n$fn\t".join("\n$fn\t",@{$self->{record}->{$f}}); + } + + $out .= "\n"; + + return $out; +} + +=head2 to_hash + +Read record with specified MFN and convert it to hash + + my $hash = $isis->to_hash($mfn); + +It has ability to convert characters (using C) from ISIS +database before creating structures enabling character re-mapping or quick +fix-up of data. + +This function returns hash which is like this: + + $hash = { + '210' => [ + { + 'c' => 'New York University press', + 'a' => 'New York', + 'd' => 'cop. 1988' + } + ], + '990' => [ + '2140', + '88', + 'HAY' + ], + }; + +You can later use that hash to produce any output from ISIS data. + +If database is created using IsisMarc, it will also have to special fields +which will be used for identifiers, C and C like this: + + '200' => [ + { + 'i1' => '1', + 'i2' => ' ' + 'a' => 'Goa', + 'f' => 'Valdo D\'Arienzo', + 'e' => 'tipografie e tipografi nel XVI secolo', + } + ], + +This method will also create additional field C<000> with MFN. + +=cut + +sub to_hash { + my $self = shift; + + my $mfn = shift || confess "need mfn!"; + + # init record to include MFN as field 000 + my $rec = { '000' => [ $mfn ] }; + + my $row = $self->fetch($mfn); + + foreach my $k (keys %{$row}) { + foreach my $l (@{$row->{$k}}) { + + # filter output + $l = $self->{'hash_filter'}->($l) if ($self->{'hash_filter'}); + + my $val; + + # has identifiers? + ($val->{'i1'},$val->{'i2'}) = ($1,$2) if ($l =~ s/^([01 #])([01 #])\^/\^/); + + # has subfields? + if ($l =~ m/\^/) { + foreach my $t (split(/\^/,$l)) { + next if (! $t); + $val->{substr($t,0,1)} = substr($t,1); + } + } else { + $val = $l; + } + + push @{$rec->{$k}}, $val; + } + } + + return $rec; +} + +=head2 tag_name + +Return name of selected tag + + print $isis->tag_name('200'); + +=cut + +sub tag_name { + my $self = shift; + my $tag = shift || return; + return $self->{'TagName'}->{$tag} || $tag; +} + + +=head2 read_cnt + +Read content of C<.CNT> file and return hash containing it. + + print Dumper($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 { + my $self = shift; + + croak "missing CNT file in ",$self->{isisdb} unless ($self->{cnt_file}); + + # Get the index information from $db.CNT + + open(my $fileCNT, $self->{cnt_file}) || croak "can't read '$self->{cnt_file}': $!"; + binmode($fileCNT); + + my $buff; + + read($fileCNT, $buff, 26) || croak "can't read first table from CNT: $!"; + $self->unpack_cnt($buff); + + read($fileCNT, $buff, 26) || croak "can't read second table from CNT: $!"; + $self->unpack_cnt($buff); + + close($fileCNT); + + return $self->{cnt}; +} + +=head2 unpack_cnt + +Unpack one of two 26 bytes fixed length record in C<.CNT> file. + +Here is definition of record: + + off key description size + 0: IDTYPE BTree type s + 2: ORDN Nodes Order s + 4: ORDF Leafs Order s + 6: N Number of Memory buffers for nodes s + 8: K Number of buffers for first level index s + 10: LIV Current number of Index Levels s + 12: POSRX Pointer to Root Record in N0x l + 16: NMAXPOS Next Available position in N0x l + 20: FMAXPOS Next available position in L0x l + 24: ABNORMAL Formal BTree normality indicator s + length: 26 bytes + +This will fill C<$self> object under C with hash. It's used by C. + +=cut + +sub unpack_cnt { + my $self = shift; + + my @flds = qw(ORDN ORDF N K LIV POSRX NMAXPOS FMAXPOS ABNORMAL); + + my $buff = shift || return; + my @arr = unpack("vvvvvvVVVv", $buff); + + print STDERR "unpack_cnt: ",join(" ",@arr),"\n" if ($self->{'debug'}); + + my $IDTYPE = shift @arr; + foreach (@flds) { + $self->{cnt}->{$IDTYPE}->{$_} = abs(shift @arr); + } +} + +1; + +=head1 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-based application, but I don't +know any details about it's version. + +=head1 AUTHOR + + Dobrica Pavlinusic + CPAN ID: DPAVLIN + dpavlin@rot13.org + http://www.rot13.org/~dpavlin/ + +This module is based heavily on code from C library to read ISIS files V0.1.1 +written in php and (c) 2000 Franck Martin and released under LGPL. + +=head1 COPYRIGHT + +This program is free software; you can redistribute +it and/or modify it under the same terms as Perl itself. + +The full text of the license can be found in the +LICENSE file included with this module. + + +=head1 SEE ALSO + +OpenIsis web site L + +perl4lib site L +