Commit | Line | Data |
51e9eee3 |
1 | package DBM::Deep::Engine::File; |
a20d9a3f |
2 | |
2120a181 |
3 | use 5.006_000; |
460b1067 |
4 | |
a20d9a3f |
5 | use strict; |
065b45be |
6 | use warnings FATAL => 'all'; |
e73f12ce |
7 | no warnings 'recursion'; |
a20d9a3f |
8 | |
51e9eee3 |
9 | use base qw( DBM::Deep::Engine ); |
10 | |
75a6a379 |
11 | use Scalar::Util (); |
d6d8e27e |
12 | |
f0276afb |
13 | use DBM::Deep::Null (); |
2c70efe1 |
14 | use DBM::Deep::Sector::File (); |
15 | use DBM::Deep::Storage::File (); |
f0276afb |
16 | |
d6ecf579 |
17 | sub sector_type { 'DBM::Deep::Sector::File' } |
19b913ce |
18 | sub iterator_class { 'DBM::Deep::Iterator::File' } |
d6ecf579 |
19 | |
9c87a079 |
20 | my $STALE_SIZE = 2; |
8db25060 |
21 | |
18bc2fa6 |
22 | # Setup file and tag signatures. These should never change. |
23 | sub SIG_FILE () { 'DPDB' } |
24 | sub SIG_HEADER () { 'h' } |
18bc2fa6 |
25 | sub SIG_NULL () { 'N' } |
26 | sub SIG_DATA () { 'D' } |
27 | sub SIG_INDEX () { 'I' } |
28 | sub SIG_BLIST () { 'B' } |
29 | sub SIG_FREE () { 'F' } |
30 | sub SIG_SIZE () { 1 } |
a4d36ff6 |
31 | # SIG_HASH and SIG_ARRAY are defined in DBM::Deep::Engine |
18bc2fa6 |
32 | |
2120a181 |
33 | # Please refer to the pack() documentation for further information |
34 | my %StP = ( |
e9b0b5f0 |
35 | 1 => 'C', # Unsigned char value (no order needed as it's just one byte) |
2120a181 |
36 | 2 => 'n', # Unsigned short in "network" (big-endian) order |
37 | 4 => 'N', # Unsigned long in "network" (big-endian) order |
38 | 8 => 'Q', # Usigned quad (no order specified, presumably machine-dependent) |
39 | ); |
00d9bd0b |
40 | |
ae6c15b8 |
41 | =head1 NAME |
42 | |
64a531e5 |
43 | DBM::Deep::Engine::File |
ae6c15b8 |
44 | |
45 | =head1 PURPOSE |
46 | |
1c62d370 |
47 | This is the engine for use with L<DBM::Deep::Storage::File>. |
ae6c15b8 |
48 | |
49 | =head1 EXTERNAL METHODS |
50 | |
ae6c15b8 |
51 | =head2 new() |
52 | |
53 | This takes a set of args. These args are described in the documentation for |
54 | L<DBM::Deep/new>. |
55 | |
56 | =cut |
57 | |
612969fb |
58 | sub new { |
59 | my $class = shift; |
60 | my ($args) = @_; |
61 | |
d426259c |
62 | $args->{storage} = DBM::Deep::Storage::File->new( $args ) |
f1879fdc |
63 | unless exists $args->{storage}; |
64 | |
612969fb |
65 | my $self = bless { |
2120a181 |
66 | byte_size => 4, |
67 | |
68 | digest => undef, |
69 | hash_size => 16, # In bytes |
70 | hash_chars => 256, # Number of chars the algorithm uses per byte |
612969fb |
71 | max_buckets => 16, |
e9b0b5f0 |
72 | num_txns => 1, # The HEAD |
2120a181 |
73 | trans_id => 0, # Default to the HEAD |
460b1067 |
74 | |
e9b0b5f0 |
75 | data_sector_size => 64, # Size in bytes of each data sector |
76 | |
2120a181 |
77 | entries => {}, # This is the list of entries for transactions |
83371fe3 |
78 | storage => undef, |
612969fb |
79 | }, $class; |
80 | |
e9b0b5f0 |
81 | # Never allow byte_size to be set directly. |
82 | delete $args->{byte_size}; |
e0098e7f |
83 | if ( defined $args->{pack_size} ) { |
84 | if ( lc $args->{pack_size} eq 'small' ) { |
2120a181 |
85 | $args->{byte_size} = 2; |
e0098e7f |
86 | } |
87 | elsif ( lc $args->{pack_size} eq 'medium' ) { |
2120a181 |
88 | $args->{byte_size} = 4; |
e0098e7f |
89 | } |
90 | elsif ( lc $args->{pack_size} eq 'large' ) { |
2120a181 |
91 | $args->{byte_size} = 8; |
e0098e7f |
92 | } |
93 | else { |
2120a181 |
94 | DBM::Deep->_throw_error( "Unknown pack_size value: '$args->{pack_size}'" ); |
e0098e7f |
95 | } |
96 | } |
97 | |
fde3db1a |
98 | # Grab the parameters we want to use |
99 | foreach my $param ( keys %$self ) { |
100 | next unless exists $args->{$param}; |
3e9498a1 |
101 | $self->{$param} = $args->{$param}; |
fde3db1a |
102 | } |
103 | |
e9b0b5f0 |
104 | my %validations = ( |
105 | max_buckets => { floor => 16, ceil => 256 }, |
106 | num_txns => { floor => 1, ceil => 255 }, |
107 | data_sector_size => { floor => 32, ceil => 256 }, |
108 | ); |
109 | |
110 | while ( my ($attr, $c) = each %validations ) { |
111 | if ( !defined $self->{$attr} |
112 | || !length $self->{$attr} |
113 | || $self->{$attr} =~ /\D/ |
114 | || $self->{$attr} < $c->{floor} |
115 | ) { |
116 | $self->{$attr} = '(undef)' if !defined $self->{$attr}; |
117 | warn "Floor of $attr is $c->{floor}. Setting it to $c->{floor} from '$self->{$attr}'\n"; |
118 | $self->{$attr} = $c->{floor}; |
119 | } |
120 | elsif ( $self->{$attr} > $c->{ceil} ) { |
121 | warn "Ceiling of $attr is $c->{ceil}. Setting it to $c->{ceil} from '$self->{$attr}'\n"; |
122 | $self->{$attr} = $c->{ceil}; |
123 | } |
e0098e7f |
124 | } |
125 | |
2120a181 |
126 | if ( !$self->{digest} ) { |
127 | require Digest::MD5; |
128 | $self->{digest} = \&Digest::MD5::md5; |
129 | } |
130 | |
260a80b4 |
131 | return $self; |
132 | } |
133 | |
2120a181 |
134 | sub read_value { |
c3aafc14 |
135 | my $self = shift; |
2120a181 |
136 | my ($obj, $key) = @_; |
137 | |
138 | # This will be a Reference sector |
d6ecf579 |
139 | my $sector = $self->load_sector( $obj->_base_offset ) |
2120a181 |
140 | or return; |
141 | |
142 | if ( $sector->staleness != $obj->_staleness ) { |
143 | return; |
144 | } |
145 | |
146 | my $key_md5 = $self->_apply_digest( $key ); |
147 | |
148 | my $value_sector = $sector->get_data_for({ |
149 | key_md5 => $key_md5, |
150 | allow_head => 1, |
151 | }); |
152 | |
153 | unless ( $value_sector ) { |
2c70efe1 |
154 | $value_sector = DBM::Deep::Sector::File::Null->new({ |
2120a181 |
155 | engine => $self, |
156 | data => undef, |
157 | }); |
158 | |
159 | $sector->write_data({ |
160 | key_md5 => $key_md5, |
161 | key => $key, |
162 | value => $value_sector, |
163 | }); |
164 | } |
165 | |
166 | return $value_sector->data; |
c3aafc14 |
167 | } |
168 | |
2120a181 |
169 | sub get_classname { |
260a80b4 |
170 | my $self = shift; |
2120a181 |
171 | my ($obj) = @_; |
260a80b4 |
172 | |
2120a181 |
173 | # This will be a Reference sector |
d6ecf579 |
174 | my $sector = $self->load_sector( $obj->_base_offset ) |
2120a181 |
175 | or DBM::Deep->_throw_error( "How did get_classname fail (no sector for '$obj')?!" ); |
612969fb |
176 | |
2120a181 |
177 | if ( $sector->staleness != $obj->_staleness ) { |
178 | return; |
179 | } |
ea2f6d67 |
180 | |
2120a181 |
181 | return $sector->get_classname; |
1bf65be7 |
182 | } |
183 | |
1cff45d7 |
184 | sub make_reference { |
185 | my $self = shift; |
186 | my ($obj, $old_key, $new_key) = @_; |
187 | |
188 | # This will be a Reference sector |
d6ecf579 |
189 | my $sector = $self->load_sector( $obj->_base_offset ) |
ae6c15b8 |
190 | or DBM::Deep->_throw_error( "How did make_reference fail (no sector for '$obj')?!" ); |
1cff45d7 |
191 | |
192 | if ( $sector->staleness != $obj->_staleness ) { |
193 | return; |
194 | } |
195 | |
196 | my $old_md5 = $self->_apply_digest( $old_key ); |
197 | |
198 | my $value_sector = $sector->get_data_for({ |
199 | key_md5 => $old_md5, |
200 | allow_head => 1, |
201 | }); |
202 | |
203 | unless ( $value_sector ) { |
2c70efe1 |
204 | $value_sector = DBM::Deep::Sector::File::Null->new({ |
1cff45d7 |
205 | engine => $self, |
206 | data => undef, |
207 | }); |
208 | |
209 | $sector->write_data({ |
210 | key_md5 => $old_md5, |
211 | key => $old_key, |
212 | value => $value_sector, |
213 | }); |
214 | } |
215 | |
2c70efe1 |
216 | if ( $value_sector->isa( 'DBM::Deep::Sector::File::Reference' ) ) { |
1cff45d7 |
217 | $sector->write_data({ |
218 | key => $new_key, |
219 | key_md5 => $self->_apply_digest( $new_key ), |
220 | value => $value_sector, |
221 | }); |
222 | $value_sector->increment_refcount; |
223 | } |
224 | else { |
225 | $sector->write_data({ |
226 | key => $new_key, |
227 | key_md5 => $self->_apply_digest( $new_key ), |
228 | value => $value_sector->clone, |
229 | }); |
230 | } |
ae6c15b8 |
231 | |
232 | return; |
1cff45d7 |
233 | } |
234 | |
a4d36ff6 |
235 | # exists returns '', not undefined. |
2120a181 |
236 | sub key_exists { |
0d0f3d5d |
237 | my $self = shift; |
2120a181 |
238 | my ($obj, $key) = @_; |
0d0f3d5d |
239 | |
2120a181 |
240 | # This will be a Reference sector |
d6ecf579 |
241 | my $sector = $self->load_sector( $obj->_base_offset ) |
2120a181 |
242 | or return ''; |
0d0f3d5d |
243 | |
2120a181 |
244 | if ( $sector->staleness != $obj->_staleness ) { |
245 | return ''; |
246 | } |
0d0f3d5d |
247 | |
2120a181 |
248 | my $data = $sector->get_data_for({ |
249 | key_md5 => $self->_apply_digest( $key ), |
250 | allow_head => 1, |
251 | }); |
20b7f047 |
252 | |
2120a181 |
253 | # exists() returns 1 or '' for true/false. |
254 | return $data ? 1 : ''; |
0d0f3d5d |
255 | } |
256 | |
2120a181 |
257 | sub delete_key { |
e064ccd1 |
258 | my $self = shift; |
2120a181 |
259 | my ($obj, $key) = @_; |
e064ccd1 |
260 | |
d6ecf579 |
261 | my $sector = $self->load_sector( $obj->_base_offset ) |
2120a181 |
262 | or return; |
460b1067 |
263 | |
2120a181 |
264 | if ( $sector->staleness != $obj->_staleness ) { |
265 | return; |
266 | } |
267 | |
268 | return $sector->delete_key({ |
269 | key_md5 => $self->_apply_digest( $key ), |
270 | allow_head => 0, |
271 | }); |
272 | } |
273 | |
274 | sub write_value { |
275 | my $self = shift; |
276 | my ($obj, $key, $value) = @_; |
277 | |
278 | my $r = Scalar::Util::reftype( $value ) || ''; |
279 | { |
280 | last if $r eq ''; |
281 | last if $r eq 'HASH'; |
282 | last if $r eq 'ARRAY'; |
e064ccd1 |
283 | |
2120a181 |
284 | DBM::Deep->_throw_error( |
285 | "Storage of references of type '$r' is not supported." |
286 | ); |
460b1067 |
287 | } |
260a80b4 |
288 | |
1cff45d7 |
289 | # This will be a Reference sector |
d6ecf579 |
290 | my $sector = $self->load_sector( $obj->_base_offset ) |
9c87a079 |
291 | or DBM::Deep->_throw_error( "Cannot write to a deleted spot in DBM::Deep." ); |
1cff45d7 |
292 | |
293 | if ( $sector->staleness != $obj->_staleness ) { |
9c87a079 |
294 | DBM::Deep->_throw_error( "Cannot write to a deleted spot in DBM::Deep." ); |
1cff45d7 |
295 | } |
296 | |
2120a181 |
297 | my ($class, $type); |
298 | if ( !defined $value ) { |
2c70efe1 |
299 | $class = 'DBM::Deep::Sector::File::Null'; |
2120a181 |
300 | } |
301 | elsif ( $r eq 'ARRAY' || $r eq 'HASH' ) { |
75a6a379 |
302 | my $tmpvar; |
303 | if ( $r eq 'ARRAY' ) { |
304 | $tmpvar = tied @$value; |
305 | } elsif ( $r eq 'HASH' ) { |
306 | $tmpvar = tied %$value; |
307 | } |
5ef7542f |
308 | |
edd45134 |
309 | if ( $tmpvar ) { |
310 | my $is_dbm_deep = eval { local $SIG{'__DIE__'}; $tmpvar->isa( 'DBM::Deep' ); }; |
311 | |
312 | unless ( $is_dbm_deep ) { |
313 | DBM::Deep->_throw_error( "Cannot store something that is tied." ); |
314 | } |
315 | |
d6d8e27e |
316 | unless ( $tmpvar->_engine->storage == $self->storage ) { |
75a6a379 |
317 | DBM::Deep->_throw_error( "Cannot store values across DBM::Deep files. Please use export() instead." ); |
5ef7542f |
318 | } |
5ef7542f |
319 | |
2c70efe1 |
320 | # First, verify if we're storing the same thing to this spot. If we |
321 | # are, then this should be a no-op. -EJS, 2008-05-19 |
d6d8e27e |
322 | my $loc = $sector->get_data_location_for({ |
323 | key_md5 => $self->_apply_digest( $key ), |
324 | allow_head => 1, |
325 | }); |
326 | |
327 | if ( defined($loc) && $loc == $tmpvar->_base_offset ) { |
1cff45d7 |
328 | return 1; |
329 | } |
330 | |
edd45134 |
331 | #XXX Can this use $loc? |
d6ecf579 |
332 | my $value_sector = $self->load_sector( $tmpvar->_base_offset ); |
d6d8e27e |
333 | $sector->write_data({ |
334 | key => $key, |
335 | key_md5 => $self->_apply_digest( $key ), |
336 | value => $value_sector, |
337 | }); |
338 | $value_sector->increment_refcount; |
339 | |
340 | return 1; |
1cff45d7 |
341 | } |
edd45134 |
342 | |
2c70efe1 |
343 | $class = 'DBM::Deep::Sector::File::Reference'; |
2120a181 |
344 | $type = substr( $r, 0, 1 ); |
345 | } |
346 | else { |
1cff45d7 |
347 | if ( tied($value) ) { |
348 | DBM::Deep->_throw_error( "Cannot store something that is tied." ); |
349 | } |
2c70efe1 |
350 | $class = 'DBM::Deep::Sector::File::Scalar'; |
460b1067 |
351 | } |
9b2370e0 |
352 | |
2c70efe1 |
353 | # Create this after loading the reference sector in case something bad |
354 | # happens. This way, we won't allocate value sector(s) needlessly. |
2120a181 |
355 | my $value_sector = $class->new({ |
356 | engine => $self, |
357 | data => $value, |
358 | type => $type, |
359 | }); |
75a6a379 |
360 | |
2120a181 |
361 | $sector->write_data({ |
362 | key => $key, |
363 | key_md5 => $self->_apply_digest( $key ), |
364 | value => $value_sector, |
365 | }); |
366 | |
c2472ede |
367 | $self->_descend( $value, $value_sector ); |
460b1067 |
368 | |
2120a181 |
369 | return 1; |
e064ccd1 |
370 | } |
371 | |
f4d0ac97 |
372 | sub setup { |
2120a181 |
373 | my $self = shift; |
374 | my ($obj) = @_; |
359a01ac |
375 | |
9c87a079 |
376 | # We're opening the file. |
377 | unless ( $obj->_base_offset ) { |
378 | my $bytes_read = $self->_read_file_header; |
118ba343 |
379 | |
9c87a079 |
380 | # Creating a new file |
381 | unless ( $bytes_read ) { |
382 | $self->_write_file_header; |
118ba343 |
383 | |
9c87a079 |
384 | # 1) Create Array/Hash entry |
2c70efe1 |
385 | my $initial_reference = DBM::Deep::Sector::File::Reference->new({ |
9c87a079 |
386 | engine => $self, |
387 | type => $obj->_type, |
388 | }); |
389 | $obj->{base_offset} = $initial_reference->offset; |
390 | $obj->{staleness} = $initial_reference->staleness; |
118ba343 |
391 | |
9c87a079 |
392 | $self->storage->flush; |
118ba343 |
393 | } |
9c87a079 |
394 | # Reading from an existing file |
395 | else { |
396 | $obj->{base_offset} = $bytes_read; |
2c70efe1 |
397 | my $initial_reference = DBM::Deep::Sector::File::Reference->new({ |
9c87a079 |
398 | engine => $self, |
399 | offset => $obj->_base_offset, |
400 | }); |
401 | unless ( $initial_reference ) { |
402 | DBM::Deep->_throw_error("Corrupted file, no master index record"); |
403 | } |
2120a181 |
404 | |
9c87a079 |
405 | unless ($obj->_type eq $initial_reference->type) { |
406 | DBM::Deep->_throw_error("File type mismatch"); |
407 | } |
f1879fdc |
408 | |
9c87a079 |
409 | $obj->{staleness} = $initial_reference->staleness; |
410 | } |
118ba343 |
411 | } |
2120a181 |
412 | |
a5bdb1ac |
413 | $self->storage->set_inode; |
414 | |
2120a181 |
415 | return 1; |
416 | } |
417 | |
418 | sub begin_work { |
419 | my $self = shift; |
420 | my ($obj) = @_; |
421 | |
422 | if ( $self->trans_id ) { |
423 | DBM::Deep->_throw_error( "Cannot begin_work within an active transaction" ); |
424 | } |
425 | |
426 | my @slots = $self->read_txn_slots; |
e9b0b5f0 |
427 | my $found; |
428 | for my $i ( 0 .. $#slots ) { |
2120a181 |
429 | next if $slots[$i]; |
e9b0b5f0 |
430 | |
2120a181 |
431 | $slots[$i] = 1; |
e9b0b5f0 |
432 | $self->set_trans_id( $i + 1 ); |
433 | $found = 1; |
2120a181 |
434 | last; |
435 | } |
e9b0b5f0 |
436 | unless ( $found ) { |
437 | DBM::Deep->_throw_error( "Cannot allocate transaction ID" ); |
438 | } |
2120a181 |
439 | $self->write_txn_slots( @slots ); |
440 | |
441 | if ( !$self->trans_id ) { |
442 | DBM::Deep->_throw_error( "Cannot begin_work - no available transactions" ); |
443 | } |
444 | |
445 | return; |
446 | } |
447 | |
448 | sub rollback { |
449 | my $self = shift; |
450 | my ($obj) = @_; |
451 | |
452 | if ( !$self->trans_id ) { |
453 | DBM::Deep->_throw_error( "Cannot rollback without an active transaction" ); |
454 | } |
455 | |
9c87a079 |
456 | # Each entry is the file location for a bucket that has a modification for |
457 | # this transaction. The entries need to be expunged. |
458 | foreach my $entry (@{ $self->get_entries } ) { |
459 | # Remove the entry here |
460 | my $read_loc = $entry |
461 | + $self->hash_size |
462 | + $self->byte_size |
463 | + $self->byte_size |
464 | + ($self->trans_id - 1) * ( $self->byte_size + $STALE_SIZE ); |
465 | |
466 | my $data_loc = $self->storage->read_at( $read_loc, $self->byte_size ); |
467 | $data_loc = unpack( $StP{$self->byte_size}, $data_loc ); |
468 | $self->storage->print_at( $read_loc, pack( $StP{$self->byte_size}, 0 ) ); |
469 | |
470 | if ( $data_loc > 1 ) { |
d6ecf579 |
471 | $self->load_sector( $data_loc )->free; |
9c87a079 |
472 | } |
db2eb673 |
473 | } |
474 | |
2120a181 |
475 | $self->clear_entries; |
70b55428 |
476 | |
2120a181 |
477 | my @slots = $self->read_txn_slots; |
e9b0b5f0 |
478 | $slots[$self->trans_id-1] = 0; |
2120a181 |
479 | $self->write_txn_slots( @slots ); |
480 | $self->inc_txn_staleness_counter( $self->trans_id ); |
481 | $self->set_trans_id( 0 ); |
6fde4ed2 |
482 | |
70b55428 |
483 | return 1; |
484 | } |
485 | |
2120a181 |
486 | sub commit { |
16d1ad9b |
487 | my $self = shift; |
2120a181 |
488 | my ($obj) = @_; |
489 | |
490 | if ( !$self->trans_id ) { |
491 | DBM::Deep->_throw_error( "Cannot commit without an active transaction" ); |
492 | } |
493 | |
9c87a079 |
494 | foreach my $entry (@{ $self->get_entries } ) { |
495 | # Overwrite the entry in head with the entry in trans_id |
496 | my $base = $entry |
497 | + $self->hash_size |
498 | + $self->byte_size; |
499 | |
500 | my $head_loc = $self->storage->read_at( $base, $self->byte_size ); |
501 | $head_loc = unpack( $StP{$self->byte_size}, $head_loc ); |
502 | |
503 | my $spot = $base + $self->byte_size + ($self->trans_id - 1) * ( $self->byte_size + $STALE_SIZE ); |
504 | my $trans_loc = $self->storage->read_at( |
505 | $spot, $self->byte_size, |
506 | ); |
507 | |
508 | $self->storage->print_at( $base, $trans_loc ); |
509 | $self->storage->print_at( |
510 | $spot, |
511 | pack( $StP{$self->byte_size} . ' ' . $StP{$STALE_SIZE}, (0) x 2 ), |
512 | ); |
513 | |
514 | if ( $head_loc > 1 ) { |
d6ecf579 |
515 | $self->load_sector( $head_loc )->free; |
9c87a079 |
516 | } |
db2eb673 |
517 | } |
518 | |
2120a181 |
519 | $self->clear_entries; |
520 | |
521 | my @slots = $self->read_txn_slots; |
e9b0b5f0 |
522 | $slots[$self->trans_id-1] = 0; |
2120a181 |
523 | $self->write_txn_slots( @slots ); |
524 | $self->inc_txn_staleness_counter( $self->trans_id ); |
525 | $self->set_trans_id( 0 ); |
526 | |
527 | return 1; |
16d1ad9b |
528 | } |
529 | |
ae6c15b8 |
530 | =head1 INTERNAL METHODS |
531 | |
51e9eee3 |
532 | The following methods are internal-use-only to DBM::Deep::Engine::File. |
ae6c15b8 |
533 | |
534 | =cut |
535 | |
536 | =head2 read_txn_slots() |
537 | |
538 | This takes no arguments. |
539 | |
540 | This will return an array with a 1 or 0 in each slot. Each spot represents one |
541 | available transaction. If the slot is 1, that transaction is taken. If it is 0, |
542 | the transaction is available. |
543 | |
544 | =cut |
545 | |
2120a181 |
546 | sub read_txn_slots { |
d4b1166e |
547 | my $self = shift; |
9c87a079 |
548 | my $bl = $self->txn_bitfield_len; |
549 | my $num_bits = $bl * 8; |
550 | return split '', unpack( 'b'.$num_bits, |
551 | $self->storage->read_at( |
552 | $self->trans_loc, $bl, |
553 | ) |
554 | ); |
2120a181 |
555 | } |
20f7b20c |
556 | |
ae6c15b8 |
557 | =head2 write_txn_slots( @slots ) |
558 | |
559 | This takes an array of 1's and 0's. This array represents the transaction slots |
560 | returned by L</read_txn_slots()>. In other words, the following is true: |
561 | |
562 | @x = read_txn_slots( write_txn_slots( @x ) ); |
563 | |
564 | (With the obviously missing object referents added back in.) |
565 | |
566 | =cut |
567 | |
2120a181 |
568 | sub write_txn_slots { |
569 | my $self = shift; |
9c87a079 |
570 | my $num_bits = $self->txn_bitfield_len * 8; |
571 | $self->storage->print_at( $self->trans_loc, |
572 | pack( 'b'.$num_bits, join('', @_) ), |
573 | ); |
2120a181 |
574 | } |
575 | |
ae6c15b8 |
576 | =head2 get_running_txn_ids() |
577 | |
578 | This takes no arguments. |
579 | |
580 | This will return an array of taken transaction IDs. This wraps L</read_txn_slots()>. |
581 | |
582 | =cut |
583 | |
2120a181 |
584 | sub get_running_txn_ids { |
585 | my $self = shift; |
586 | my @transactions = $self->read_txn_slots; |
ae6c15b8 |
587 | my @trans_ids = map { $_+1 } grep { $transactions[$_] } 0 .. $#transactions; |
2120a181 |
588 | } |
589 | |
ae6c15b8 |
590 | =head2 get_txn_staleness_counter( $trans_id ) |
591 | |
592 | This will return the staleness counter for the given transaction ID. Please see |
593 | L</TRANSACTION STALENESS> for more information. |
594 | |
595 | =cut |
596 | |
2120a181 |
597 | sub get_txn_staleness_counter { |
598 | my $self = shift; |
9c87a079 |
599 | my ($trans_id) = @_; |
600 | |
601 | # Hardcode staleness of 0 for the HEAD |
602 | return 0 unless $trans_id; |
603 | |
604 | return unpack( $StP{$STALE_SIZE}, |
605 | $self->storage->read_at( |
606 | $self->trans_loc + $self->txn_bitfield_len + $STALE_SIZE * ($trans_id - 1), |
607 | $STALE_SIZE, |
608 | ) |
609 | ); |
d4b1166e |
610 | } |
611 | |
ae6c15b8 |
612 | =head2 inc_txn_staleness_counter( $trans_id ) |
613 | |
614 | This will increment the staleness counter for the given transaction ID. Please see |
615 | L</TRANSACTION STALENESS> for more information. |
616 | |
617 | =cut |
618 | |
2120a181 |
619 | sub inc_txn_staleness_counter { |
d4b1166e |
620 | my $self = shift; |
9c87a079 |
621 | my ($trans_id) = @_; |
622 | |
623 | # Hardcode staleness of 0 for the HEAD |
624 | return 0 unless $trans_id; |
625 | |
626 | $self->storage->print_at( |
627 | $self->trans_loc + $self->txn_bitfield_len + $STALE_SIZE * ($trans_id - 1), |
628 | pack( $StP{$STALE_SIZE}, $self->get_txn_staleness_counter( $trans_id ) + 1 ), |
629 | ); |
2120a181 |
630 | } |
20f7b20c |
631 | |
ae6c15b8 |
632 | =head2 get_entries() |
633 | |
634 | This takes no arguments. |
635 | |
636 | This returns a list of all the sectors that have been modified by this transaction. |
637 | |
638 | =cut |
639 | |
2120a181 |
640 | sub get_entries { |
641 | my $self = shift; |
642 | return [ keys %{ $self->{entries}{$self->trans_id} ||= {} } ]; |
d4b1166e |
643 | } |
644 | |
ae6c15b8 |
645 | =head2 add_entry( $trans_id, $location ) |
646 | |
3b90cc56 |
647 | This takes a transaction ID and a file location and marks the sector at that |
648 | location as having been modified by the transaction identified by $trans_id. |
ae6c15b8 |
649 | |
650 | This returns nothing. |
651 | |
652 | B<NOTE>: Unlike all the other _entries() methods, there are several cases where |
653 | C<< $trans_id != $self->trans_id >> for this method. |
654 | |
655 | =cut |
656 | |
2120a181 |
657 | sub add_entry { |
ea2f6d67 |
658 | my $self = shift; |
9c87a079 |
659 | my ($trans_id, $loc) = @_; |
97d40a0a |
660 | |
2120a181 |
661 | $self->{entries}{$trans_id} ||= {}; |
9c87a079 |
662 | $self->{entries}{$trans_id}{$loc} = undef; |
2120a181 |
663 | } |
ea2f6d67 |
664 | |
ae6c15b8 |
665 | =head2 reindex_entry( $old_loc, $new_loc ) |
666 | |
3b90cc56 |
667 | This takes two locations (old and new, respectively). If a location that has |
668 | been modified by this transaction is subsequently reindexed due to a bucketlist |
ae6c15b8 |
669 | overflowing, then the entries hash needs to be made aware of this change. |
670 | |
671 | This returns nothing. |
672 | |
673 | =cut |
674 | |
2120a181 |
675 | sub reindex_entry { |
676 | my $self = shift; |
9c87a079 |
677 | my ($old_loc, $new_loc) = @_; |
2120a181 |
678 | |
679 | TRANS: |
680 | while ( my ($trans_id, $locs) = each %{ $self->{entries} } ) { |
9c87a079 |
681 | if ( exists $locs->{$old_loc} ) { |
682 | delete $locs->{$old_loc}; |
683 | $locs->{$new_loc} = undef; |
695c88b1 |
684 | next TRANS; |
2120a181 |
685 | } |
ea2f6d67 |
686 | } |
ea2f6d67 |
687 | } |
688 | |
ae6c15b8 |
689 | =head2 clear_entries() |
690 | |
3b90cc56 |
691 | This takes no arguments. It will clear the entries list for the running |
692 | transaction. |
ae6c15b8 |
693 | |
694 | This returns nothing. |
695 | |
696 | =cut |
697 | |
2120a181 |
698 | sub clear_entries { |
d4b1166e |
699 | my $self = shift; |
2120a181 |
700 | delete $self->{entries}{$self->trans_id}; |
701 | } |
eea0d863 |
702 | |
ae6c15b8 |
703 | =head2 _write_file_header() |
704 | |
705 | This writes the file header for a new file. This will write the various settings |
706 | that set how the file is interpreted. |
707 | |
708 | =head2 _read_file_header() |
709 | |
710 | This reads the file header from an existing file. This will read the various |
711 | settings that set how the file is interpreted. |
712 | |
713 | =cut |
714 | |
9c87a079 |
715 | { |
51e9eee3 |
716 | my $header_fixed = length( __PACKAGE__->SIG_FILE ) + 1 + 4 + 4; |
9c87a079 |
717 | my $this_file_version = 3; |
16d1ad9b |
718 | |
9c87a079 |
719 | sub _write_file_header { |
720 | my $self = shift; |
75be6413 |
721 | |
9c87a079 |
722 | my $nt = $self->num_txns; |
723 | my $bl = $self->txn_bitfield_len; |
75be6413 |
724 | |
9c87a079 |
725 | my $header_var = 1 + 1 + 1 + 1 + $bl + $STALE_SIZE * ($nt - 1) + 3 * $self->byte_size; |
75be6413 |
726 | |
9c87a079 |
727 | my $loc = $self->storage->request_space( $header_fixed + $header_var ); |
75be6413 |
728 | |
9c87a079 |
729 | $self->storage->print_at( $loc, |
51e9eee3 |
730 | $self->SIG_FILE, |
731 | $self->SIG_HEADER, |
9c87a079 |
732 | pack('N', $this_file_version), # At this point, we're at 9 bytes |
733 | pack('N', $header_var), # header size |
734 | # --- Above is $header_fixed. Below is $header_var |
735 | pack('C', $self->byte_size), |
75be6413 |
736 | |
9c87a079 |
737 | # These shenanigans are to allow a 256 within a C |
738 | pack('C', $self->max_buckets - 1), |
739 | pack('C', $self->data_sector_size - 1), |
75be6413 |
740 | |
9c87a079 |
741 | pack('C', $nt), |
742 | pack('C' . $bl, 0 ), # Transaction activeness bitfield |
743 | pack($StP{$STALE_SIZE}.($nt-1), 0 x ($nt-1) ), # Transaction staleness counters |
744 | pack($StP{$self->byte_size}, 0), # Start of free chain (blist size) |
745 | pack($StP{$self->byte_size}, 0), # Start of free chain (data size) |
746 | pack($StP{$self->byte_size}, 0), # Start of free chain (index size) |
747 | ); |
75be6413 |
748 | |
9c87a079 |
749 | #XXX Set these less fragilely |
750 | $self->set_trans_loc( $header_fixed + 4 ); |
751 | $self->set_chains_loc( $header_fixed + 4 + $bl + $STALE_SIZE * ($nt-1) ); |
75be6413 |
752 | |
9c87a079 |
753 | return; |
badf847c |
754 | } |
7b1e1aa1 |
755 | |
9c87a079 |
756 | sub _read_file_header { |
badf847c |
757 | my $self = shift; |
75be6413 |
758 | |
9c87a079 |
759 | my $buffer = $self->storage->read_at( 0, $header_fixed ); |
760 | return unless length($buffer); |
2603d86e |
761 | |
9c87a079 |
762 | my ($file_signature, $sig_header, $file_version, $size) = unpack( |
763 | 'A4 A N N', $buffer |
764 | ); |
75be6413 |
765 | |
51e9eee3 |
766 | unless ( $file_signature eq $self->SIG_FILE ) { |
9c87a079 |
767 | $self->storage->close; |
768 | DBM::Deep->_throw_error( "Signature not found -- file is not a Deep DB" ); |
769 | } |
7b1e1aa1 |
770 | |
51e9eee3 |
771 | unless ( $sig_header eq $self->SIG_HEADER ) { |
9c87a079 |
772 | $self->storage->close; |
773 | DBM::Deep->_throw_error( "Pre-1.00 file version found" ); |
774 | } |
775 | |
776 | unless ( $file_version == $this_file_version ) { |
777 | $self->storage->close; |
778 | DBM::Deep->_throw_error( |
779 | "Wrong file version found - " . $file_version . |
780 | " - expected " . $this_file_version |
781 | ); |
782 | } |
783 | |
784 | my $buffer2 = $self->storage->read_at( undef, $size ); |
785 | my @values = unpack( 'C C C C', $buffer2 ); |
786 | |
787 | if ( @values != 4 || grep { !defined } @values ) { |
788 | $self->storage->close; |
789 | DBM::Deep->_throw_error("Corrupted file - bad header"); |
790 | } |
791 | |
792 | #XXX Add warnings if values weren't set right |
793 | @{$self}{qw(byte_size max_buckets data_sector_size num_txns)} = @values; |
794 | |
795 | # These shenangians are to allow a 256 within a C |
796 | $self->{max_buckets} += 1; |
797 | $self->{data_sector_size} += 1; |
798 | |
799 | my $bl = $self->txn_bitfield_len; |
800 | |
801 | my $header_var = scalar(@values) + $bl + $STALE_SIZE * ($self->num_txns - 1) + 3 * $self->byte_size; |
802 | unless ( $size == $header_var ) { |
803 | $self->storage->close; |
804 | DBM::Deep->_throw_error( "Unexpected size found ($size <-> $header_var)." ); |
badf847c |
805 | } |
7b1e1aa1 |
806 | |
9c87a079 |
807 | $self->set_trans_loc( $header_fixed + scalar(@values) ); |
808 | $self->set_chains_loc( $header_fixed + scalar(@values) + $bl + $STALE_SIZE * ($self->num_txns - 1) ); |
809 | |
810 | return length($buffer) + length($buffer2); |
7b1e1aa1 |
811 | } |
75be6413 |
812 | } |
813 | |
ae6c15b8 |
814 | =head2 _apply_digest( @stuff ) |
815 | |
816 | This will apply the digest methd (default to Digest::MD5::md5) to the arguments |
817 | passed in and return the result. |
818 | |
819 | =cut |
820 | |
9c87a079 |
821 | sub _apply_digest { |
a8d2331c |
822 | my $self = shift; |
9c87a079 |
823 | return $self->{digest}->(@_); |
a8d2331c |
824 | } |
825 | |
ae6c15b8 |
826 | =head2 _add_free_blist_sector( $offset, $size ) |
827 | |
828 | =head2 _add_free_data_sector( $offset, $size ) |
829 | |
830 | =head2 _add_free_index_sector( $offset, $size ) |
831 | |
832 | These methods are all wrappers around _add_free_sector(), providing the proper |
833 | chain offset ($multiple) for the sector type. |
834 | |
835 | =cut |
836 | |
9c87a079 |
837 | sub _add_free_blist_sector { shift->_add_free_sector( 0, @_ ) } |
838 | sub _add_free_data_sector { shift->_add_free_sector( 1, @_ ) } |
839 | sub _add_free_index_sector { shift->_add_free_sector( 2, @_ ) } |
840 | |
ae6c15b8 |
841 | =head2 _add_free_sector( $multiple, $offset, $size ) |
842 | |
843 | _add_free_sector() takes the offset into the chains location, the offset of the |
844 | sector, and the size of that sector. It will mark the sector as a free sector |
845 | and put it into the list of sectors that are free of this type for use later. |
846 | |
847 | This returns nothing. |
848 | |
849 | B<NOTE>: $size is unused? |
850 | |
851 | =cut |
852 | |
9c87a079 |
853 | sub _add_free_sector { |
00d9bd0b |
854 | my $self = shift; |
9c87a079 |
855 | my ($multiple, $offset, $size) = @_; |
856 | |
857 | my $chains_offset = $multiple * $self->byte_size; |
858 | |
859 | my $storage = $self->storage; |
860 | |
861 | # Increment staleness. |
862 | # XXX Can this increment+modulo be done by "&= 0x1" ? |
51e9eee3 |
863 | my $staleness = unpack( $StP{$STALE_SIZE}, $storage->read_at( $offset + $self->SIG_SIZE, $STALE_SIZE ) ); |
9c87a079 |
864 | $staleness = ($staleness + 1 ) % ( 2 ** ( 8 * $STALE_SIZE ) ); |
51e9eee3 |
865 | $storage->print_at( $offset + $self->SIG_SIZE, pack( $StP{$STALE_SIZE}, $staleness ) ); |
9c87a079 |
866 | |
867 | my $old_head = $storage->read_at( $self->chains_loc + $chains_offset, $self->byte_size ); |
868 | |
869 | $storage->print_at( $self->chains_loc + $chains_offset, |
870 | pack( $StP{$self->byte_size}, $offset ), |
871 | ); |
872 | |
873 | # Record the old head in the new sector after the signature and staleness counter |
51e9eee3 |
874 | $storage->print_at( $offset + $self->SIG_SIZE + $STALE_SIZE, $old_head ); |
00d9bd0b |
875 | } |
876 | |
ae6c15b8 |
877 | =head2 _request_blist_sector( $size ) |
878 | |
879 | =head2 _request_data_sector( $size ) |
880 | |
881 | =head2 _request_index_sector( $size ) |
882 | |
883 | These methods are all wrappers around _request_sector(), providing the proper |
884 | chain offset ($multiple) for the sector type. |
885 | |
886 | =cut |
887 | |
9c87a079 |
888 | sub _request_blist_sector { shift->_request_sector( 0, @_ ) } |
889 | sub _request_data_sector { shift->_request_sector( 1, @_ ) } |
890 | sub _request_index_sector { shift->_request_sector( 2, @_ ) } |
891 | |
ae6c15b8 |
892 | =head2 _request_sector( $multiple $size ) |
893 | |
894 | This takes the offset into the chains location and the size of that sector. |
895 | |
896 | This returns the object with the sector. If there is an available free sector of |
897 | that type, then it will be reused. If there isn't one, then a new one will be |
898 | allocated. |
899 | |
900 | =cut |
901 | |
9c87a079 |
902 | sub _request_sector { |
a8d2331c |
903 | my $self = shift; |
9c87a079 |
904 | my ($multiple, $size) = @_; |
905 | |
906 | my $chains_offset = $multiple * $self->byte_size; |
907 | |
908 | my $old_head = $self->storage->read_at( $self->chains_loc + $chains_offset, $self->byte_size ); |
909 | my $loc = unpack( $StP{$self->byte_size}, $old_head ); |
910 | |
911 | # We don't have any free sectors of the right size, so allocate a new one. |
912 | unless ( $loc ) { |
913 | my $offset = $self->storage->request_space( $size ); |
914 | |
915 | # Zero out the new sector. This also guarantees correct increases |
916 | # in the filesize. |
917 | $self->storage->print_at( $offset, chr(0) x $size ); |
a8d2331c |
918 | |
9c87a079 |
919 | return $offset; |
920 | } |
921 | |
922 | # Read the new head after the signature and the staleness counter |
51e9eee3 |
923 | my $new_head = $self->storage->read_at( $loc + $self->SIG_SIZE + $STALE_SIZE, $self->byte_size ); |
9c87a079 |
924 | $self->storage->print_at( $self->chains_loc + $chains_offset, $new_head ); |
925 | $self->storage->print_at( |
51e9eee3 |
926 | $loc + $self->SIG_SIZE + $STALE_SIZE, |
9c87a079 |
927 | pack( $StP{$self->byte_size}, 0 ), |
928 | ); |
929 | |
930 | return $loc; |
a8d2331c |
931 | } |
932 | |
f0276afb |
933 | =head2 ACCESSORS |
934 | |
935 | The following are readonly attributes. |
936 | |
937 | =over 4 |
938 | |
f0276afb |
939 | =item * byte_size |
940 | |
941 | =item * hash_size |
942 | |
943 | =item * hash_chars |
944 | |
945 | =item * num_txns |
946 | |
947 | =item * max_buckets |
948 | |
949 | =item * blank_md5 |
950 | |
951 | =item * data_sector_size |
952 | |
953 | =item * txn_bitfield_len |
954 | |
955 | =back |
956 | |
957 | =cut |
f1879fdc |
958 | |
2120a181 |
959 | sub byte_size { $_[0]{byte_size} } |
960 | sub hash_size { $_[0]{hash_size} } |
961 | sub hash_chars { $_[0]{hash_chars} } |
962 | sub num_txns { $_[0]{num_txns} } |
963 | sub max_buckets { $_[0]{max_buckets} } |
964 | sub blank_md5 { chr(0) x $_[0]->hash_size } |
e9b0b5f0 |
965 | sub data_sector_size { $_[0]{data_sector_size} } |
966 | |
967 | # This is a calculated value |
968 | sub txn_bitfield_len { |
969 | my $self = shift; |
970 | unless ( exists $self->{txn_bitfield_len} ) { |
971 | my $temp = ($self->num_txns) / 8; |
972 | if ( $temp > int( $temp ) ) { |
973 | $temp = int( $temp ) + 1; |
974 | } |
975 | $self->{txn_bitfield_len} = $temp; |
976 | } |
977 | return $self->{txn_bitfield_len}; |
978 | } |
8db25060 |
979 | |
f0276afb |
980 | =pod |
981 | |
982 | The following are read/write attributes. |
983 | |
984 | =over 4 |
985 | |
986 | =item * trans_id / set_trans_id( $new_id ) |
987 | |
988 | =item * trans_loc / set_trans_loc( $new_loc ) |
989 | |
990 | =item * chains_loc / set_chains_loc( $new_loc ) |
991 | |
992 | =back |
993 | |
994 | =cut |
995 | |
2120a181 |
996 | sub trans_id { $_[0]{trans_id} } |
997 | sub set_trans_id { $_[0]{trans_id} = $_[1] } |
8db25060 |
998 | |
2120a181 |
999 | sub trans_loc { $_[0]{trans_loc} } |
1000 | sub set_trans_loc { $_[0]{trans_loc} = $_[1] } |
1001 | |
1002 | sub chains_loc { $_[0]{chains_loc} } |
1003 | sub set_chains_loc { $_[0]{chains_loc} = $_[1] } |
1004 | |
580e5ee2 |
1005 | sub supports { |
1006 | shift; |
1007 | my ($feature) = @_; |
1008 | |
1009 | return 1 if $feature eq 'transactions'; |
1010 | return; |
1011 | } |
1012 | |
e73f12ce |
1013 | sub clear { |
1014 | my $self = shift; |
1015 | my $obj = shift; |
1016 | |
1017 | my $sector = $self->load_sector( $obj->_base_offset ) |
1018 | or return; |
1019 | |
1020 | return unless $sector->staleness == $obj->_staleness; |
1021 | |
1022 | $sector->clear; |
1023 | |
1024 | return; |
1025 | } |
1026 | |
f0276afb |
1027 | =head2 _dump_file() |
1028 | |
3b90cc56 |
1029 | This method takes no arguments. It's used to print out a textual representation |
1030 | of the DBM::Deep DB file. It assumes the file is not-corrupted. |
f0276afb |
1031 | |
1032 | =cut |
1033 | |
888453b9 |
1034 | sub _dump_file { |
1035 | my $self = shift; |
1036 | |
1037 | # Read the header |
9c87a079 |
1038 | my $spot = $self->_read_file_header(); |
888453b9 |
1039 | |
1040 | my %types = ( |
1041 | 0 => 'B', |
1042 | 1 => 'D', |
1043 | 2 => 'I', |
1044 | ); |
1045 | |
1046 | my %sizes = ( |
1047 | 'D' => $self->data_sector_size, |
2c70efe1 |
1048 | 'B' => DBM::Deep::Sector::File::BucketList->new({engine=>$self,offset=>1})->size, |
1049 | 'I' => DBM::Deep::Sector::File::Index->new({engine=>$self,offset=>1})->size, |
888453b9 |
1050 | ); |
1051 | |
1052 | my $return = ""; |
c57b19c6 |
1053 | |
1054 | # Header values |
1055 | $return .= "NumTxns: " . $self->num_txns . $/; |
1056 | |
888453b9 |
1057 | # Read the free sector chains |
1058 | my %sectors; |
1059 | foreach my $multiple ( 0 .. 2 ) { |
1060 | $return .= "Chains($types{$multiple}):"; |
1061 | my $old_loc = $self->chains_loc + $multiple * $self->byte_size; |
1062 | while ( 1 ) { |
1063 | my $loc = unpack( |
1064 | $StP{$self->byte_size}, |
1065 | $self->storage->read_at( $old_loc, $self->byte_size ), |
1066 | ); |
1067 | |
1068 | # We're now out of free sectors of this kind. |
1069 | unless ( $loc ) { |
1070 | last; |
1071 | } |
1072 | |
1073 | $sectors{ $types{$multiple} }{ $loc } = undef; |
51e9eee3 |
1074 | $old_loc = $loc + $self->SIG_SIZE + $STALE_SIZE; |
888453b9 |
1075 | $return .= " $loc"; |
1076 | } |
1077 | $return .= $/; |
1078 | } |
1079 | |
1080 | SECTOR: |
1081 | while ( $spot < $self->storage->{end} ) { |
1082 | # Read each sector in order. |
d6ecf579 |
1083 | my $sector = $self->load_sector( $spot ); |
888453b9 |
1084 | if ( !$sector ) { |
1085 | # Find it in the free-sectors that were found already |
1086 | foreach my $type ( keys %sectors ) { |
1087 | if ( exists $sectors{$type}{$spot} ) { |
1088 | my $size = $sizes{$type}; |
1089 | $return .= sprintf "%08d: %s %04d\n", $spot, 'F' . $type, $size; |
1090 | $spot += $size; |
1091 | next SECTOR; |
1092 | } |
1093 | } |
1094 | |
1095 | die "********\n$return\nDidn't find free sector for $spot in chains\n********\n"; |
1096 | } |
1097 | else { |
1098 | $return .= sprintf "%08d: %s %04d", $spot, $sector->type, $sector->size; |
1099 | if ( $sector->type eq 'D' ) { |
1100 | $return .= ' ' . $sector->data; |
1101 | } |
1102 | elsif ( $sector->type eq 'A' || $sector->type eq 'H' ) { |
1103 | $return .= ' REF: ' . $sector->get_refcount; |
1104 | } |
1105 | elsif ( $sector->type eq 'B' ) { |
1106 | foreach my $bucket ( $sector->chopped_up ) { |
1107 | $return .= "\n "; |
1108 | $return .= sprintf "%08d", unpack($StP{$self->byte_size}, |
1109 | substr( $bucket->[-1], $self->hash_size, $self->byte_size), |
1110 | ); |
c57b19c6 |
1111 | my $l = unpack( $StP{$self->byte_size}, |
1112 | substr( $bucket->[-1], |
1113 | $self->hash_size + $self->byte_size, |
1114 | $self->byte_size, |
1115 | ), |
1116 | ); |
1117 | $return .= sprintf " %08d", $l; |
1118 | foreach my $txn ( 0 .. $self->num_txns - 2 ) { |
888453b9 |
1119 | my $l = unpack( $StP{$self->byte_size}, |
1120 | substr( $bucket->[-1], |
c57b19c6 |
1121 | $self->hash_size + 2 * $self->byte_size + $txn * ($self->byte_size + $STALE_SIZE), |
888453b9 |
1122 | $self->byte_size, |
1123 | ), |
1124 | ); |
1125 | $return .= sprintf " %08d", $l; |
1126 | } |
1127 | } |
1128 | } |
1129 | $return .= $/; |
1130 | |
1131 | $spot += $sector->size; |
1132 | } |
1133 | } |
1134 | |
1135 | return $return; |
1136 | } |
1137 | |
a20d9a3f |
1138 | 1; |
1139 | __END__ |