1 |
package IsisDB; |
package Biblio::Isis; |
2 |
use strict; |
use strict; |
3 |
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4 |
use Carp; |
use Carp; |
5 |
use File::Glob qw(:globally :nocase); |
use File::Glob qw(:globally :nocase); |
6 |
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use Data::Dumper; |
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7 |
BEGIN { |
BEGIN { |
8 |
use Exporter (); |
use Exporter (); |
9 |
use vars qw ($VERSION @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS); |
use vars qw ($VERSION @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS); |
10 |
$VERSION = 0.07; |
$VERSION = 0.20; |
11 |
@ISA = qw (Exporter); |
@ISA = qw (Exporter); |
12 |
#Give a hoot don't pollute, do not export more than needed by default |
#Give a hoot don't pollute, do not export more than needed by default |
13 |
@EXPORT = qw (); |
@EXPORT = qw (); |
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19 |
=head1 NAME |
=head1 NAME |
20 |
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|
21 |
IsisDB - Read CDS/ISIS, WinISIS and IsisMarc database |
Biblio::Isis - Read CDS/ISIS, WinISIS and IsisMarc database |
22 |
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23 |
=head1 SYNOPSIS |
=head1 SYNOPSIS |
24 |
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|
25 |
use IsisDB; |
use Biblio::Isis; |
26 |
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|
27 |
my $isis = new IsisDB( |
my $isis = new Biblio::Isis( |
28 |
isisdb => './cds/cds', |
isisdb => './cds/cds', |
29 |
); |
); |
30 |
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|
31 |
for(my $mfn = 1; $mfn <= $isis->{'maxmfn'}; $mfn++) { |
for(my $mfn = 1; $mfn <= $isis->count; $mfn++) { |
32 |
print $isis->to_ascii($mfn),"\n"; |
print $isis->to_ascii($mfn),"\n"; |
33 |
} |
} |
34 |
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|
35 |
=head1 DESCRIPTION |
=head1 DESCRIPTION |
36 |
|
|
37 |
This module will read ISIS databases created by DOS CDS/ISIS, WinIsis or |
This module will read ISIS databases created by DOS CDS/ISIS, WinIsis or |
38 |
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 |
39 |
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seems to depriciate it's old C<XS> bindings for perl. |
40 |
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|
41 |
It can create hash values from data in ISIS database (using C<to_hash>), |
It can create hash values from data in ISIS database (using C<to_hash>), |
42 |
ASCII dump (using C<to_ascii>) or just hash with field names and packed |
ASCII dump (using C<to_ascii>) or just hash with field names and packed |
49 |
It also has support for identifiers (only if ISIS database is created by |
It also has support for identifiers (only if ISIS database is created by |
50 |
IsisMarc), see C<to_hash>. |
IsisMarc), see C<to_hash>. |
51 |
|
|
52 |
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 |
53 |
library. However, since it's written in perl, it's platform independent (so |
library. However, since it's written in perl, it's platform independent (so |
54 |
you don't need C compiler), and can be easily modified. I hope that it |
you don't need C compiler), and can be easily modified. I hope that it |
55 |
creates data structures which are easier to use than ones created by |
creates data structures which are easier to use than ones created by |
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|
80 |
Open ISIS database |
Open ISIS database |
81 |
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|
82 |
my $isis = new IsisDB( |
my $isis = new Biblio::Isis( |
83 |
isisdb => './cds/cds', |
isisdb => './cds/cds', |
84 |
read_fdt => 1, |
read_fdt => 1, |
85 |
include_deleted => 1, |
include_deleted => 1, |
117 |
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|
118 |
=item debug |
=item debug |
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|
120 |
Dump a B<lot> of debugging output. |
Dump a B<lot> of debugging output even at level 1. For even more increase level. |
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=back |
=back |
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It will also set C<$isis-E<gt>{'maxmfn'}> which is maximum MFN stored in database. |
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124 |
=cut |
=cut |
125 |
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126 |
sub new { |
sub new { |
145 |
push @must_exist, "fdt" if ($self->{read_fdt}); |
push @must_exist, "fdt" if ($self->{read_fdt}); |
146 |
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|
147 |
foreach my $ext (@must_exist) { |
foreach my $ext (@must_exist) { |
148 |
confess "missing ",uc($ext)," file in ",$self->{isisdb} unless ($self->{$ext."_file"}); |
unless ($self->{$ext."_file"}) { |
149 |
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carp "missing ",uc($ext)," file in ",$self->{isisdb}; |
150 |
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return; |
151 |
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} |
152 |
} |
} |
153 |
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154 |
print STDERR "## using files: ",join(" ",@isis_files),"\n" if ($self->{debug}); |
if ($self->{debug}) { |
155 |
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print STDERR "## using files: ",join(" ",@isis_files),"\n"; |
156 |
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eval "use Data::Dump"; |
157 |
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158 |
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if (! $@) { |
159 |
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*Dumper = *Data::Dump::dump; |
160 |
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} else { |
161 |
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use Data::Dumper; |
162 |
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} |
163 |
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} |
164 |
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# if you want to read .FDT file use read_fdt argument when creating class! |
# if you want to read .FDT file use read_fdt argument when creating class! |
166 |
if ($self->{read_fdt} && -e $self->{fdt_file}) { |
if ($self->{read_fdt} && -e $self->{fdt_file}) { |
168 |
# read the $db.FDT file for tags |
# read the $db.FDT file for tags |
169 |
my $fieldzone=0; |
my $fieldzone=0; |
170 |
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171 |
open(fileFDT, $self->{fdt_file}) || croak "can't read '$self->{fdt_file}': $!"; |
open(my $fileFDT, $self->{fdt_file}) || croak "can't read '$self->{fdt_file}': $!"; |
172 |
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binmode($fileFDT); |
173 |
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|
174 |
while (<fileFDT>) { |
while (<$fileFDT>) { |
175 |
chomp; |
chomp; |
176 |
if ($fieldzone) { |
if ($fieldzone) { |
177 |
my $name=substr($_,0,30); |
my $name=substr($_,0,30); |
188 |
} |
} |
189 |
} |
} |
190 |
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|
191 |
close(fileFDT); |
close($fileFDT); |
192 |
} |
} |
193 |
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|
194 |
# Get the Maximum MFN from $db.MST |
# Get the Maximum MFN from $db.MST |
195 |
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|
196 |
open($self->{'fileMST'}, $self->{mst_file}) || croak "can't open '$self->{mst_file}': $!"; |
open($self->{'fileMST'}, $self->{mst_file}) || croak "can't open '$self->{mst_file}': $!"; |
197 |
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binmode($self->{'fileMST'}); |
198 |
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199 |
# MST format: (* = 32 bit signed) |
# MST format: (* = 32 bit signed) |
200 |
# CTLMFN* always 0 |
# CTLMFN* always 0 |
202 |
# NXTMFB* last block allocated to master file |
# NXTMFB* last block allocated to master file |
203 |
# NXTMFP offset to next available position in last block |
# NXTMFP offset to next available position in last block |
204 |
# MFTYPE always 0 for user db file (1 for system) |
# MFTYPE always 0 for user db file (1 for system) |
205 |
seek($self->{'fileMST'},4,0); |
seek($self->{'fileMST'},4,0) || croak "can't seek to offset 0 in MST: $!"; |
206 |
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207 |
my $buff; |
my $buff; |
208 |
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209 |
read($self->{'fileMST'}, $buff, 4); |
read($self->{'fileMST'}, $buff, 4) || croak "can't read NXTMFN from MST: $!"; |
210 |
$self->{'NXTMFN'}=unpack("l",$buff) || carp "NXTNFN is zero"; |
$self->{'NXTMFN'}=unpack("V",$buff) || croak "NXTNFN is zero"; |
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# save maximum MFN |
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$self->{'maxmfn'} = $self->{'NXTMFN'} - 1; |
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211 |
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212 |
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print STDERR "## self ",Dumper($self),"\n" if ($self->{debug}); |
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print STDERR Dumper($self),"\n" if ($self->{debug}); |
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214 |
# open files for later |
# open files for later |
215 |
open($self->{'fileXRF'}, $self->{xrf_file}) || croak "can't open '$self->{xrf_file}': $!"; |
open($self->{'fileXRF'}, $self->{xrf_file}) || croak "can't open '$self->{xrf_file}': $!"; |
216 |
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binmode($self->{'fileXRF'}); |
217 |
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|
218 |
$self ? return $self : return undef; |
$self ? return $self : return undef; |
219 |
} |
} |
220 |
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=head2 read_cnt |
=head2 count |
222 |
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223 |
This function is not really used by module, but can be useful to find info |
Return number of records in database |
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about your index (if debugging it for example). |
|
224 |
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|
225 |
print Dumper($isis->read_cnt); |
print $isis->count; |
226 |
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227 |
=cut |
=cut |
228 |
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229 |
sub read_cnt { |
sub count { |
230 |
my $self = shift; |
my $self = shift; |
231 |
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return $self->{'NXTMFN'} - 1; |
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confess "missing CNT file in ",$self->{isisdb} unless ($self->{cnt_file}); |
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# Get the index information from $db.CNT |
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open(fileCNT, $self->{cnt_file}) || croak "can't read '$self->{cnt_file}': $!"; |
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# There is two 26 Bytes fixed lenght records |
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# 0: IDTYPE BTree type 16 |
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# 2: ORDN Nodes Order 16 |
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# 4: ORDF Leafs Order 16 |
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# 6: N Number of Memory buffers for nodes 16 |
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# 8: K Number of buffers for first level index 16 |
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# 10: LIV Current number of Index Levels 16 |
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# 12: POSRX* Pointer to Root Record in N0x 32 |
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# 16: NMAXPOS* Next Available position in N0x 32 |
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# 20: FMAXPOS* Next available position in L0x 32 |
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# 24: ABNORMAL Formal BTree normality indicator 16 |
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# length: 26 bytes |
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sub unpack_cnt { |
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my $self = shift; |
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my @flds = qw(ORDN ORDF N K LIV POSRX NMAXPOS FMAXPOS ABNORMAL); |
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my $buff = shift || return; |
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my @arr = unpack("ssssssllls", $buff); |
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print STDERR "unpack_cnt: ",join(" ",@arr),"\n" if ($self->{'debug'}); |
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my $IDTYPE = shift @arr; |
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foreach (@flds) { |
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$self->{cnt}->{$IDTYPE}->{$_} = abs(shift @arr); |
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} |
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} |
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my $buff; |
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read(fileCNT, $buff, 26); |
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$self->unpack_cnt($buff); |
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read(fileCNT, $buff, 26); |
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$self->unpack_cnt($buff); |
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close(fileCNT); |
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return $self->{cnt}; |
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232 |
} |
} |
233 |
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234 |
=head2 fetch |
=head2 fetch |
254 |
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|
255 |
# is mfn allready in memory? |
# is mfn allready in memory? |
256 |
my $old_mfn = $self->{'current_mfn'} || -1; |
my $old_mfn = $self->{'current_mfn'} || -1; |
257 |
return if ($mfn == $old_mfn); |
return $self->{record} if ($mfn == $old_mfn); |
258 |
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259 |
print STDERR "## fetch: $mfn\n" if ($self->{debug}); |
print STDERR "## fetch: $mfn\n" if ($self->{debug}); |
260 |
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266 |
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267 |
my $buff; |
my $buff; |
268 |
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269 |
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# delete old record |
270 |
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delete $self->{record}; |
271 |
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|
272 |
# read XRFMFB abd XRFMFP |
# read XRFMFB abd XRFMFP |
273 |
read($self->{'fileXRF'}, $buff, 4); |
read($self->{'fileXRF'}, $buff, 4); |
274 |
my $pointer=unpack("l",$buff) || carp "pointer is null"; |
my $pointer=unpack("V",$buff); |
275 |
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if (! $pointer) { |
276 |
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if ($self->{include_deleted}) { |
277 |
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return; |
278 |
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} else { |
279 |
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warn "pointer for MFN $mfn is null\n"; |
280 |
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return; |
281 |
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} |
282 |
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} |
283 |
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284 |
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# check for logically deleted record |
285 |
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if ($pointer & 0x80000000) { |
286 |
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print STDERR "## record $mfn is logically deleted\n" if ($self->{debug}); |
287 |
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$self->{deleted} = $mfn; |
288 |
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289 |
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return unless $self->{include_deleted}; |
290 |
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291 |
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# abs |
292 |
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$pointer = ($pointer ^ 0xffffffff) + 1; |
293 |
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} |
294 |
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295 |
my $XRFMFB = int($pointer/2048); |
my $XRFMFB = int($pointer/2048); |
296 |
my $XRFMFP = $pointer - ($XRFMFB*2048); |
my $XRFMFP = $pointer - ($XRFMFB*2048); |
297 |
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|
298 |
# (XRFMFB - 1) * 512 + XRFMFP |
# (XRFMFB - 1) * 512 + XRFMFP |
299 |
# why do i have to do XRFMFP % 1024 ? |
# why do i have to do XRFMFP % 1024 ? |
300 |
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|
301 |
my $blk_off = (($XRFMFB - 1) * 512) + ($XRFMFP % 1024); |
my $blk_off = (($XRFMFB - 1) * 512) + ($XRFMFP % 512); |
302 |
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|
303 |
print STDERR "## pointer: $pointer XRFMFB: $XRFMFB XRFMFP: $XRFMFP offset: $blk_off\n" if ($self->{'debug'}); |
print STDERR "## pointer: $pointer XRFMFB: $XRFMFB XRFMFP: $XRFMFP offset: $blk_off\n" if ($self->{'debug'}); |
304 |
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|
305 |
# Get Record Information |
# Get Record Information |
306 |
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|
307 |
seek($self->{'fileMST'},$blk_off,0); |
seek($self->{'fileMST'},$blk_off,0) || croak "can't seek to $blk_off: $!"; |
308 |
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|
309 |
read($self->{'fileMST'}, $buff, 4); |
read($self->{'fileMST'}, $buff, 4) || croak "can't read 4 bytes at offset $blk_off from MST file: $!"; |
310 |
my $value=unpack("l",$buff); |
my $value=unpack("V",$buff); |
311 |
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|
312 |
print STDERR "## offset for rowid $value is $blk_off (blk $XRFMFB off $XRFMFP)\n" if ($self->{debug}); |
print STDERR "## offset for rowid $value is $blk_off (blk $XRFMFB off $XRFMFP)\n" if ($self->{debug}); |
313 |
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|
314 |
if ($value!=$mfn) { |
if ($value!=$mfn) { |
315 |
carp "Error: MFN ".$mfn." not found in MST(".$value.")"; |
if ($value == 0) { |
316 |
#return; # XXX deleted record? |
print STDERR "## record $mfn is physically deleted\n" if ($self->{debug}); |
317 |
} |
$self->{deleted} = $mfn; |
318 |
|
return; |
319 |
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} |
320 |
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|
321 |
# $MFRL=$self->Read16($fileMST); |
carp "Error: MFN ".$mfn." not found in MST file, found $value"; |
322 |
# $MFBWB=$self->Read32($fileMST); |
return; |
323 |
# $MFBWP=$self->Read16($fileMST); |
} |
|
# $BASE=$self->Read16($fileMST); |
|
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# $NVF=$self->Read16($fileMST); |
|
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# $STATUS=$self->Read16($fileMST); |
|
324 |
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325 |
read($self->{'fileMST'}, $buff, 14); |
read($self->{'fileMST'}, $buff, 14); |
326 |
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327 |
my ($MFRL,$MFBWB,$MFBWP,$BASE,$NVF,$STATUS) = unpack("slssss", $buff); |
my ($MFRL,$MFBWB,$MFBWP,$BASE,$NVF,$STATUS) = unpack("vVvvvv", $buff); |
328 |
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|
329 |
print STDERR "## MFRL: $MFRL MFBWB: $MFBWB MFBWP: $MFBWP BASE: $BASE NVF: $NVF STATUS: $STATUS\n" if ($self->{debug}); |
print STDERR "## MFRL: $MFRL MFBWB: $MFBWB MFBWP: $MFBWP BASE: $BASE NVF: $NVF STATUS: $STATUS\n" if ($self->{debug}); |
330 |
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331 |
# delete old record |
warn "MFRL $MFRL is not even number" unless ($MFRL % 2 == 0); |
|
delete $self->{record}; |
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## FIXME this is a bug |
|
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if (! $self->{'include_deleted'} && $MFRL < 0) { |
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print "## logically deleted record $mfn, skipping...\n" if ($self->{debug}); |
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return; |
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} |
|
332 |
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|
333 |
warn "BASE is not 18+6*NVF" unless ($BASE == 18 + 6 * $NVF); |
warn "BASE is not 18+6*NVF" unless ($BASE == 18 + 6 * $NVF); |
334 |
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|
344 |
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|
345 |
for (my $i = 0 ; $i < $NVF ; $i++) { |
for (my $i = 0 ; $i < $NVF ; $i++) { |
346 |
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|
347 |
# $TAG=$self->Read16($fileMST); |
my ($TAG,$POS,$LEN) = unpack("vvv", substr($buff,$i * 6, 6)); |
|
# $POS=$self->Read16($fileMST); |
|
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# $LEN=$self->Read16($fileMST); |
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my ($TAG,$POS,$LEN) = unpack("sss", substr($buff,$i * 6, 6)); |
|
348 |
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|
349 |
print STDERR "## TAG: $TAG POS: $POS LEN: $LEN\n" if ($self->{debug}); |
print STDERR "## TAG: $TAG POS: $POS LEN: $LEN\n" if ($self->{debug}); |
350 |
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380 |
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|
381 |
$self->{'current_mfn'} = $mfn; |
$self->{'current_mfn'} = $mfn; |
382 |
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|
383 |
print Dumper($self),"\n" if ($self->{debug}); |
print STDERR Dumper($self),"\n" if ($self->{debug}); |
384 |
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|
385 |
return $self->{'record'}; |
return $self->{'record'}; |
386 |
} |
} |
387 |
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388 |
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=head2 mfn |
389 |
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|
390 |
|
Returns current MFN position |
391 |
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392 |
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my $mfn = $isis->mfn; |
393 |
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394 |
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=cut |
395 |
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396 |
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# This function should be simple return $self->{current_mfn}, |
397 |
|
# but if new is called with _hack_mfn it becomes setter. |
398 |
|
# It's useful in tests when setting $isis->{record} directly |
399 |
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|
400 |
|
sub mfn { |
401 |
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my $self = shift; |
402 |
|
return $self->{current_mfn}; |
403 |
|
}; |
404 |
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|
405 |
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|
406 |
=head2 to_ascii |
=head2 to_ascii |
407 |
|
|
408 |
Dump ASCII output of record with specified MFN |
Returns ASCII output of record with specified MFN |
409 |
|
|
410 |
print $isis->to_ascii(42); |
print $isis->to_ascii(42); |
411 |
|
|
412 |
It outputs something like this: |
This outputs something like this: |
413 |
|
|
414 |
210 ^aNew York^cNew York University press^dcop. 1988 |
210 ^aNew York^cNew York University press^dcop. 1988 |
415 |
990 2140 |
990 2140 |
426 |
|
|
427 |
my $mfn = shift || croak "need MFN"; |
my $mfn = shift || croak "need MFN"; |
428 |
|
|
429 |
my $rec = $self->fetch($mfn); |
my $rec = $self->fetch($mfn) || return; |
430 |
|
|
431 |
my $out = "0\t$mfn"; |
my $out = "0\t$mfn"; |
432 |
|
|
446 |
|
|
447 |
my $hash = $isis->to_hash($mfn); |
my $hash = $isis->to_hash($mfn); |
448 |
|
|
449 |
It has ability to convert characters (using C<hash_filter> from ISIS |
It has ability to convert characters (using C<hash_filter>) from ISIS |
450 |
database before creating structures enabling character re-mapping or quick |
database before creating structures enabling character re-mapping or quick |
451 |
fix-up of data. |
fix-up of data. |
452 |
|
|
482 |
} |
} |
483 |
], |
], |
484 |
|
|
485 |
|
In case there are repeatable subfields in record, this will create |
486 |
|
following structure: |
487 |
|
|
488 |
|
'900' => [ { |
489 |
|
'a' => [ 'foo', 'bar', 'baz' ], |
490 |
|
}] |
491 |
|
|
492 |
This method will also create additional field C<000> with MFN. |
This method will also create additional field C<000> with MFN. |
493 |
|
|
494 |
=cut |
=cut |
501 |
# init record to include MFN as field 000 |
# init record to include MFN as field 000 |
502 |
my $rec = { '000' => [ $mfn ] }; |
my $rec = { '000' => [ $mfn ] }; |
503 |
|
|
504 |
my $row = $self->fetch($mfn); |
my $row = $self->fetch($mfn) || return; |
505 |
|
|
506 |
foreach my $k (keys %{$row}) { |
foreach my $k (keys %{$row}) { |
507 |
foreach my $l (@{$row->{$k}}) { |
foreach my $l (@{$row->{$k}}) { |
508 |
|
|
509 |
# filter output |
# filter output |
510 |
$l = $self->{'hash_filter'}->($l) if ($self->{'hash_filter'}); |
if ($self->{'hash_filter'}) { |
511 |
|
$l = $self->{'hash_filter'}->($l); |
512 |
|
next unless defined($l); |
513 |
|
} |
514 |
|
|
515 |
my $val; |
my $val; |
516 |
|
|
517 |
# has identifiers? |
# has identifiers? |
518 |
($val->{'i1'},$val->{'i2'}) = ($1,$2) if ($l =~ s/^([01 #])([01 #])//); |
($val->{'i1'},$val->{'i2'}) = ($1,$2) if ($l =~ s/^([01 #])([01 #])\^/\^/); |
519 |
|
|
520 |
# has subfields? |
# has subfields? |
521 |
if ($l =~ m/\^/) { |
if ($l =~ m/\^/) { |
522 |
foreach my $t (split(/\^/,$l)) { |
foreach my $t (split(/\^/,$l)) { |
523 |
next if (! $t); |
next if (! $t); |
524 |
$val->{substr($t,0,1)} = substr($t,1); |
my ($sf,$v) = (substr($t,0,1), substr($t,1)); |
525 |
|
# FIXME make this option ! |
526 |
|
next unless ($v); |
527 |
|
# warn "### $k^$sf:$v",$/ if ($self->{debug} > 1); |
528 |
|
|
529 |
|
# FIXME array return optional, by default unroll to ' ; ' |
530 |
|
if (ref( $val->{$sf} ) eq 'ARRAY') { |
531 |
|
|
532 |
|
push @{ $val->{$sf} }, $v; |
533 |
|
} elsif (defined( $val->{$sf} )) { |
534 |
|
# convert scalar field to array |
535 |
|
$val->{$sf} = [ $val->{$sf}, $v ]; |
536 |
|
} else { |
537 |
|
$val->{$sf} = $v; |
538 |
|
} |
539 |
} |
} |
540 |
} else { |
} else { |
541 |
$val = $l; |
$val = $l; |
562 |
return $self->{'TagName'}->{$tag} || $tag; |
return $self->{'TagName'}->{$tag} || $tag; |
563 |
} |
} |
564 |
|
|
565 |
|
|
566 |
|
=head2 read_cnt |
567 |
|
|
568 |
|
Read content of C<.CNT> file and return hash containing it. |
569 |
|
|
570 |
|
print Dumper($isis->read_cnt); |
571 |
|
|
572 |
|
This function is not used by module (C<.CNT> files are not required for this |
573 |
|
module to work), but it can be useful to examine your index (while debugging |
574 |
|
for example). |
575 |
|
|
576 |
|
=cut |
577 |
|
|
578 |
|
sub read_cnt { |
579 |
|
my $self = shift; |
580 |
|
|
581 |
|
croak "missing CNT file in ",$self->{isisdb} unless ($self->{cnt_file}); |
582 |
|
|
583 |
|
# Get the index information from $db.CNT |
584 |
|
|
585 |
|
open(my $fileCNT, $self->{cnt_file}) || croak "can't read '$self->{cnt_file}': $!"; |
586 |
|
binmode($fileCNT); |
587 |
|
|
588 |
|
my $buff; |
589 |
|
|
590 |
|
read($fileCNT, $buff, 26) || croak "can't read first table from CNT: $!"; |
591 |
|
$self->unpack_cnt($buff); |
592 |
|
|
593 |
|
read($fileCNT, $buff, 26) || croak "can't read second table from CNT: $!"; |
594 |
|
$self->unpack_cnt($buff); |
595 |
|
|
596 |
|
close($fileCNT); |
597 |
|
|
598 |
|
return $self->{cnt}; |
599 |
|
} |
600 |
|
|
601 |
|
=head2 unpack_cnt |
602 |
|
|
603 |
|
Unpack one of two 26 bytes fixed length record in C<.CNT> file. |
604 |
|
|
605 |
|
Here is definition of record: |
606 |
|
|
607 |
|
off key description size |
608 |
|
0: IDTYPE BTree type s |
609 |
|
2: ORDN Nodes Order s |
610 |
|
4: ORDF Leafs Order s |
611 |
|
6: N Number of Memory buffers for nodes s |
612 |
|
8: K Number of buffers for first level index s |
613 |
|
10: LIV Current number of Index Levels s |
614 |
|
12: POSRX Pointer to Root Record in N0x l |
615 |
|
16: NMAXPOS Next Available position in N0x l |
616 |
|
20: FMAXPOS Next available position in L0x l |
617 |
|
24: ABNORMAL Formal BTree normality indicator s |
618 |
|
length: 26 bytes |
619 |
|
|
620 |
|
This will fill C<$self> object under C<cnt> with hash. It's used by C<read_cnt>. |
621 |
|
|
622 |
|
=cut |
623 |
|
|
624 |
|
sub unpack_cnt { |
625 |
|
my $self = shift; |
626 |
|
|
627 |
|
my @flds = qw(ORDN ORDF N K LIV POSRX NMAXPOS FMAXPOS ABNORMAL); |
628 |
|
|
629 |
|
my $buff = shift || return; |
630 |
|
my @arr = unpack("vvvvvvVVVv", $buff); |
631 |
|
|
632 |
|
print STDERR "unpack_cnt: ",join(" ",@arr),"\n" if ($self->{'debug'}); |
633 |
|
|
634 |
|
my $IDTYPE = shift @arr; |
635 |
|
foreach (@flds) { |
636 |
|
$self->{cnt}->{$IDTYPE}->{$_} = abs(shift @arr); |
637 |
|
} |
638 |
|
} |
639 |
|
|
640 |
1; |
1; |
641 |
|
|
642 |
=head1 BUGS |
=head1 BUGS |
643 |
|
|
644 |
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 |
645 |
|
some variations in input databases which has been tested with this module. |
646 |
|
When I was in doubt, I assumed that OpenIsis's implementation was right |
647 |
|
(except for obvious bugs). |
648 |
|
|
649 |
|
However, every effort has been made to test this module with as much |
650 |
|
databases (and programs that create them) as possible. |
651 |
|
|
652 |
|
I would be very greatful for success or failure reports about usage of this |
653 |
|
module with databases from programs other than WinIsis and IsisMarc. I had |
654 |
|
tested this against ouput of one C<isis.dll>-based application, but I don't |
655 |
|
know any details about it's version. |
656 |
|
|
657 |
|
=head1 VERSIONS |
658 |
|
|
659 |
|
You can find version dependencies documented here |
660 |
|
|
661 |
|
=over 8 |
662 |
|
|
663 |
|
=item 0.20 |
664 |
|
|
665 |
|
Added C<< $isis->mfn >> and support for repeatable subfields |
666 |
|
|
667 |
|
=back |
668 |
|
|
669 |
=head1 AUTHOR |
=head1 AUTHOR |
670 |
|
|