1 package DBM::Deep::Engine;
6 use warnings FATAL => 'all';
8 use DBM::Deep::Engine::Sector::BucketList;
9 use DBM::Deep::Engine::Sector::Index;
10 use DBM::Deep::Engine::Sector::Null;
11 use DBM::Deep::Engine::Sector::Reference;
12 use DBM::Deep::Engine::Sector::Scalar;
13 use DBM::Deep::Iterator;
15 # Never import symbols into our namespace. We are a class, not a library.
22 # * Every method in here assumes that the storage has been appropriately
23 # safeguarded. This can be anything from flock() to some sort of manual
24 # mutex. But, it's the caller's responsability to make sure that this has
27 # Setup file and tag signatures. These should never change.
28 sub SIG_FILE () { 'DPDB' }
29 sub SIG_HEADER () { 'h' }
30 sub SIG_HASH () { 'H' }
31 sub SIG_ARRAY () { 'A' }
32 sub SIG_NULL () { 'N' }
33 sub SIG_DATA () { 'D' }
34 sub SIG_INDEX () { 'I' }
35 sub SIG_BLIST () { 'B' }
36 sub SIG_FREE () { 'F' }
41 # Please refer to the pack() documentation for further information
43 1 => 'C', # Unsigned char value (no order needed as it's just one byte)
44 2 => 'n', # Unsigned short in "network" (big-endian) order
45 4 => 'N', # Unsigned long in "network" (big-endian) order
46 8 => 'Q', # Usigned quad (no order specified, presumably machine-dependent)
48 sub StP { $StP{$_[1]} }
50 ################################################################################
60 hash_size => 16, # In bytes
61 hash_chars => 256, # Number of chars the algorithm uses per byte
63 num_txns => 1, # The HEAD
64 trans_id => 0, # Default to the HEAD
66 data_sector_size => 64, # Size in bytes of each data sector
68 entries => {}, # This is the list of entries for transactions
72 # Never allow byte_size to be set directly.
73 delete $args->{byte_size};
74 if ( defined $args->{pack_size} ) {
75 if ( lc $args->{pack_size} eq 'small' ) {
76 $args->{byte_size} = 2;
78 elsif ( lc $args->{pack_size} eq 'medium' ) {
79 $args->{byte_size} = 4;
81 elsif ( lc $args->{pack_size} eq 'large' ) {
82 $args->{byte_size} = 8;
85 DBM::Deep->_throw_error( "Unknown pack_size value: '$args->{pack_size}'" );
89 # Grab the parameters we want to use
90 foreach my $param ( keys %$self ) {
91 next unless exists $args->{$param};
92 $self->{$param} = $args->{$param};
96 max_buckets => { floor => 16, ceil => 256 },
97 num_txns => { floor => 1, ceil => 255 },
98 data_sector_size => { floor => 32, ceil => 256 },
101 while ( my ($attr, $c) = each %validations ) {
102 if ( !defined $self->{$attr}
103 || !length $self->{$attr}
104 || $self->{$attr} =~ /\D/
105 || $self->{$attr} < $c->{floor}
107 $self->{$attr} = '(undef)' if !defined $self->{$attr};
108 warn "Floor of $attr is $c->{floor}. Setting it to $c->{floor} from '$self->{$attr}'\n";
109 $self->{$attr} = $c->{floor};
111 elsif ( $self->{$attr} > $c->{ceil} ) {
112 warn "Ceiling of $attr is $c->{ceil}. Setting it to $c->{ceil} from '$self->{$attr}'\n";
113 $self->{$attr} = $c->{ceil};
117 if ( !$self->{digest} ) {
119 $self->{digest} = \&Digest::MD5::md5;
125 ################################################################################
129 my ($obj, $key) = @_;
131 # This will be a Reference sector
132 my $sector = $self->_load_sector( $obj->_base_offset )
135 if ( $sector->staleness != $obj->_staleness ) {
139 my $key_md5 = $self->_apply_digest( $key );
141 my $value_sector = $sector->get_data_for({
146 unless ( $value_sector ) {
147 $value_sector = DBM::Deep::Engine::Sector::Null->new({
152 $sector->write_data({
155 value => $value_sector,
159 return $value_sector->data;
166 # This will be a Reference sector
167 my $sector = $self->_load_sector( $obj->_base_offset )
168 or DBM::Deep->_throw_error( "How did get_classname fail (no sector for '$obj')?!" );
170 if ( $sector->staleness != $obj->_staleness ) {
174 return $sector->get_classname;
179 my ($obj, $old_key, $new_key) = @_;
181 # This will be a Reference sector
182 my $sector = $self->_load_sector( $obj->_base_offset )
183 or DBM::Deep->_throw_error( "How did get_classname fail (no sector for '$obj')?!" );
185 if ( $sector->staleness != $obj->_staleness ) {
189 my $old_md5 = $self->_apply_digest( $old_key );
191 my $value_sector = $sector->get_data_for({
196 unless ( $value_sector ) {
197 $value_sector = DBM::Deep::Engine::Sector::Null->new({
202 $sector->write_data({
205 value => $value_sector,
209 if ( $value_sector->isa( 'DBM::Deep::Engine::Sector::Reference' ) ) {
210 $sector->write_data({
212 key_md5 => $self->_apply_digest( $new_key ),
213 value => $value_sector,
215 $value_sector->increment_refcount;
218 $sector->write_data({
220 key_md5 => $self->_apply_digest( $new_key ),
221 value => $value_sector->clone,
228 my ($obj, $key) = @_;
230 # This will be a Reference sector
231 my $sector = $self->_load_sector( $obj->_base_offset )
234 if ( $sector->staleness != $obj->_staleness ) {
238 my $data = $sector->get_data_for({
239 key_md5 => $self->_apply_digest( $key ),
243 # exists() returns 1 or '' for true/false.
244 return $data ? 1 : '';
249 my ($obj, $key) = @_;
251 my $sector = $self->_load_sector( $obj->_base_offset )
254 if ( $sector->staleness != $obj->_staleness ) {
258 return $sector->delete_key({
259 key_md5 => $self->_apply_digest( $key ),
266 my ($obj, $key, $value) = @_;
268 my $r = Scalar::Util::reftype( $value ) || '';
271 last if $r eq 'HASH';
272 last if $r eq 'ARRAY';
274 DBM::Deep->_throw_error(
275 "Storage of references of type '$r' is not supported."
279 # This will be a Reference sector
280 my $sector = $self->_load_sector( $obj->_base_offset )
281 or DBM::Deep->_throw_error( "Cannot write to a deleted spot in DBM::Deep." );
283 if ( $sector->staleness != $obj->_staleness ) {
284 DBM::Deep->_throw_error( "Cannot write to a deleted spot in DBM::Deep." );
288 if ( !defined $value ) {
289 $class = 'DBM::Deep::Engine::Sector::Null';
291 elsif ( $r eq 'ARRAY' || $r eq 'HASH' ) {
293 if ( $r eq 'ARRAY' ) {
294 $tmpvar = tied @$value;
295 } elsif ( $r eq 'HASH' ) {
296 $tmpvar = tied %$value;
300 my $is_dbm_deep = eval { local $SIG{'__DIE__'}; $tmpvar->isa( 'DBM::Deep' ); };
302 unless ( $is_dbm_deep ) {
303 DBM::Deep->_throw_error( "Cannot store something that is tied." );
306 unless ( $tmpvar->_engine->storage == $self->storage ) {
307 DBM::Deep->_throw_error( "Cannot store values across DBM::Deep files. Please use export() instead." );
310 # First, verify if we're storing the same thing to this spot. If we are, then
311 # this should be a no-op. -EJS, 2008-05-19
312 my $loc = $sector->get_data_location_for({
313 key_md5 => $self->_apply_digest( $key ),
317 if ( defined($loc) && $loc == $tmpvar->_base_offset ) {
321 #XXX Can this use $loc?
322 my $value_sector = $self->_load_sector( $tmpvar->_base_offset );
323 $sector->write_data({
325 key_md5 => $self->_apply_digest( $key ),
326 value => $value_sector,
328 $value_sector->increment_refcount;
333 $class = 'DBM::Deep::Engine::Sector::Reference';
334 $type = substr( $r, 0, 1 );
337 if ( tied($value) ) {
338 DBM::Deep->_throw_error( "Cannot store something that is tied." );
340 $class = 'DBM::Deep::Engine::Sector::Scalar';
343 # Create this after loading the reference sector in case something bad happens.
344 # This way, we won't allocate value sector(s) needlessly.
345 my $value_sector = $class->new({
351 $sector->write_data({
353 key_md5 => $self->_apply_digest( $key ),
354 value => $value_sector,
357 # This code is to make sure we write all the values in the $value to the disk
358 # and to make sure all changes to $value after the assignment are reflected
359 # on disk. This may be counter-intuitive at first, but it is correct dwimmery.
360 # NOTE - simply tying $value won't perform a STORE on each value. Hence, the
361 # copy to a temp value.
362 if ( $r eq 'ARRAY' ) {
364 tie @$value, 'DBM::Deep', {
365 base_offset => $value_sector->offset,
366 staleness => $value_sector->staleness,
367 storage => $self->storage,
371 bless $value, 'DBM::Deep::Array' unless Scalar::Util::blessed( $value );
373 elsif ( $r eq 'HASH' ) {
375 tie %$value, 'DBM::Deep', {
376 base_offset => $value_sector->offset,
377 staleness => $value_sector->staleness,
378 storage => $self->storage,
383 bless $value, 'DBM::Deep::Hash' unless Scalar::Util::blessed( $value );
389 # XXX Add staleness here
392 my ($obj, $prev_key) = @_;
394 # XXX Need to add logic about resetting the iterator if any key in the reference has changed
395 unless ( $prev_key ) {
396 $obj->{iterator} = DBM::Deep::Iterator->new({
397 base_offset => $obj->_base_offset,
402 return $obj->{iterator}->get_next_key( $obj );
405 ################################################################################
411 # We're opening the file.
412 unless ( $obj->_base_offset ) {
413 my $bytes_read = $self->_read_file_header;
415 # Creating a new file
416 unless ( $bytes_read ) {
417 $self->_write_file_header;
419 # 1) Create Array/Hash entry
420 my $initial_reference = DBM::Deep::Engine::Sector::Reference->new({
424 $obj->{base_offset} = $initial_reference->offset;
425 $obj->{staleness} = $initial_reference->staleness;
427 $self->storage->flush;
429 # Reading from an existing file
431 $obj->{base_offset} = $bytes_read;
432 my $initial_reference = DBM::Deep::Engine::Sector::Reference->new({
434 offset => $obj->_base_offset,
436 unless ( $initial_reference ) {
437 DBM::Deep->_throw_error("Corrupted file, no master index record");
440 unless ($obj->_type eq $initial_reference->type) {
441 DBM::Deep->_throw_error("File type mismatch");
444 $obj->{staleness} = $initial_reference->staleness;
455 if ( $self->trans_id ) {
456 DBM::Deep->_throw_error( "Cannot begin_work within an active transaction" );
459 my @slots = $self->read_txn_slots;
461 for my $i ( 0 .. $#slots ) {
465 $self->set_trans_id( $i + 1 );
470 DBM::Deep->_throw_error( "Cannot allocate transaction ID" );
472 $self->write_txn_slots( @slots );
474 if ( !$self->trans_id ) {
475 DBM::Deep->_throw_error( "Cannot begin_work - no available transactions" );
485 if ( !$self->trans_id ) {
486 DBM::Deep->_throw_error( "Cannot rollback without an active transaction" );
489 # Each entry is the file location for a bucket that has a modification for
490 # this transaction. The entries need to be expunged.
491 foreach my $entry (@{ $self->get_entries } ) {
492 # Remove the entry here
493 my $read_loc = $entry
497 + ($self->trans_id - 1) * ( $self->byte_size + $STALE_SIZE );
499 my $data_loc = $self->storage->read_at( $read_loc, $self->byte_size );
500 $data_loc = unpack( $StP{$self->byte_size}, $data_loc );
501 $self->storage->print_at( $read_loc, pack( $StP{$self->byte_size}, 0 ) );
503 if ( $data_loc > 1 ) {
504 $self->_load_sector( $data_loc )->free;
508 $self->clear_entries;
510 my @slots = $self->read_txn_slots;
511 $slots[$self->trans_id-1] = 0;
512 $self->write_txn_slots( @slots );
513 $self->inc_txn_staleness_counter( $self->trans_id );
514 $self->set_trans_id( 0 );
523 if ( !$self->trans_id ) {
524 DBM::Deep->_throw_error( "Cannot commit without an active transaction" );
527 foreach my $entry (@{ $self->get_entries } ) {
528 # Overwrite the entry in head with the entry in trans_id
533 my $head_loc = $self->storage->read_at( $base, $self->byte_size );
534 $head_loc = unpack( $StP{$self->byte_size}, $head_loc );
536 my $spot = $base + $self->byte_size + ($self->trans_id - 1) * ( $self->byte_size + $STALE_SIZE );
537 my $trans_loc = $self->storage->read_at(
538 $spot, $self->byte_size,
541 $self->storage->print_at( $base, $trans_loc );
542 $self->storage->print_at(
544 pack( $StP{$self->byte_size} . ' ' . $StP{$STALE_SIZE}, (0) x 2 ),
547 if ( $head_loc > 1 ) {
548 $self->_load_sector( $head_loc )->free;
552 $self->clear_entries;
554 my @slots = $self->read_txn_slots;
555 $slots[$self->trans_id-1] = 0;
556 $self->write_txn_slots( @slots );
557 $self->inc_txn_staleness_counter( $self->trans_id );
558 $self->set_trans_id( 0 );
565 my $bl = $self->txn_bitfield_len;
566 my $num_bits = $bl * 8;
567 return split '', unpack( 'b'.$num_bits,
568 $self->storage->read_at(
569 $self->trans_loc, $bl,
574 sub write_txn_slots {
576 my $num_bits = $self->txn_bitfield_len * 8;
577 $self->storage->print_at( $self->trans_loc,
578 pack( 'b'.$num_bits, join('', @_) ),
582 sub get_running_txn_ids {
584 my @transactions = $self->read_txn_slots;
585 my @trans_ids = map { $_+1} grep { $transactions[$_] } 0 .. $#transactions;
588 sub get_txn_staleness_counter {
592 # Hardcode staleness of 0 for the HEAD
593 return 0 unless $trans_id;
595 return unpack( $StP{$STALE_SIZE},
596 $self->storage->read_at(
597 $self->trans_loc + $self->txn_bitfield_len + $STALE_SIZE * ($trans_id - 1),
603 sub inc_txn_staleness_counter {
607 # Hardcode staleness of 0 for the HEAD
608 return 0 unless $trans_id;
610 $self->storage->print_at(
611 $self->trans_loc + $self->txn_bitfield_len + $STALE_SIZE * ($trans_id - 1),
612 pack( $StP{$STALE_SIZE}, $self->get_txn_staleness_counter( $trans_id ) + 1 ),
618 return [ keys %{ $self->{entries}{$self->trans_id} ||= {} } ];
623 my ($trans_id, $loc) = @_;
625 $self->{entries}{$trans_id} ||= {};
626 $self->{entries}{$trans_id}{$loc} = undef;
629 # If the buckets are being relocated because of a reindexing, the entries
630 # mechanism needs to be made aware of it.
633 my ($old_loc, $new_loc) = @_;
636 while ( my ($trans_id, $locs) = each %{ $self->{entries} } ) {
637 if ( exists $locs->{$old_loc} ) {
638 delete $locs->{$old_loc};
639 $locs->{$new_loc} = undef;
647 delete $self->{entries}{$self->trans_id};
650 ################################################################################
653 my $header_fixed = length( SIG_FILE ) + 1 + 4 + 4;
654 my $this_file_version = 3;
656 sub _write_file_header {
659 my $nt = $self->num_txns;
660 my $bl = $self->txn_bitfield_len;
662 my $header_var = 1 + 1 + 1 + 1 + $bl + $STALE_SIZE * ($nt - 1) + 3 * $self->byte_size;
664 my $loc = $self->storage->request_space( $header_fixed + $header_var );
666 $self->storage->print_at( $loc,
669 pack('N', $this_file_version), # At this point, we're at 9 bytes
670 pack('N', $header_var), # header size
671 # --- Above is $header_fixed. Below is $header_var
672 pack('C', $self->byte_size),
674 # These shenanigans are to allow a 256 within a C
675 pack('C', $self->max_buckets - 1),
676 pack('C', $self->data_sector_size - 1),
679 pack('C' . $bl, 0 ), # Transaction activeness bitfield
680 pack($StP{$STALE_SIZE}.($nt-1), 0 x ($nt-1) ), # Transaction staleness counters
681 pack($StP{$self->byte_size}, 0), # Start of free chain (blist size)
682 pack($StP{$self->byte_size}, 0), # Start of free chain (data size)
683 pack($StP{$self->byte_size}, 0), # Start of free chain (index size)
686 #XXX Set these less fragilely
687 $self->set_trans_loc( $header_fixed + 4 );
688 $self->set_chains_loc( $header_fixed + 4 + $bl + $STALE_SIZE * ($nt-1) );
693 sub _read_file_header {
696 my $buffer = $self->storage->read_at( 0, $header_fixed );
697 return unless length($buffer);
699 my ($file_signature, $sig_header, $file_version, $size) = unpack(
703 unless ( $file_signature eq SIG_FILE ) {
704 $self->storage->close;
705 DBM::Deep->_throw_error( "Signature not found -- file is not a Deep DB" );
708 unless ( $sig_header eq SIG_HEADER ) {
709 $self->storage->close;
710 DBM::Deep->_throw_error( "Pre-1.00 file version found" );
713 unless ( $file_version == $this_file_version ) {
714 $self->storage->close;
715 DBM::Deep->_throw_error(
716 "Wrong file version found - " . $file_version .
717 " - expected " . $this_file_version
721 my $buffer2 = $self->storage->read_at( undef, $size );
722 my @values = unpack( 'C C C C', $buffer2 );
724 if ( @values != 4 || grep { !defined } @values ) {
725 $self->storage->close;
726 DBM::Deep->_throw_error("Corrupted file - bad header");
729 #XXX Add warnings if values weren't set right
730 @{$self}{qw(byte_size max_buckets data_sector_size num_txns)} = @values;
732 # These shenangians are to allow a 256 within a C
733 $self->{max_buckets} += 1;
734 $self->{data_sector_size} += 1;
736 my $bl = $self->txn_bitfield_len;
738 my $header_var = scalar(@values) + $bl + $STALE_SIZE * ($self->num_txns - 1) + 3 * $self->byte_size;
739 unless ( $size == $header_var ) {
740 $self->storage->close;
741 DBM::Deep->_throw_error( "Unexpected size found ($size <-> $header_var)." );
744 $self->set_trans_loc( $header_fixed + scalar(@values) );
745 $self->set_chains_loc( $header_fixed + scalar(@values) + $bl + $STALE_SIZE * ($self->num_txns - 1) );
747 return length($buffer) + length($buffer2);
755 # Add a catch for offset of 0 or 1
756 return if !$offset || $offset <= 1;
758 my $type = $self->storage->read_at( $offset, 1 );
759 return if $type eq chr(0);
761 if ( $type eq $self->SIG_ARRAY || $type eq $self->SIG_HASH ) {
762 return DBM::Deep::Engine::Sector::Reference->new({
768 # XXX Don't we need key_md5 here?
769 elsif ( $type eq $self->SIG_BLIST ) {
770 return DBM::Deep::Engine::Sector::BucketList->new({
776 elsif ( $type eq $self->SIG_INDEX ) {
777 return DBM::Deep::Engine::Sector::Index->new({
783 elsif ( $type eq $self->SIG_NULL ) {
784 return DBM::Deep::Engine::Sector::Null->new({
790 elsif ( $type eq $self->SIG_DATA ) {
791 return DBM::Deep::Engine::Sector::Scalar->new({
797 # This was deleted from under us, so just return and let the caller figure it out.
798 elsif ( $type eq $self->SIG_FREE ) {
802 DBM::Deep->_throw_error( "'$offset': Don't know what to do with type '$type'" );
807 return $self->{digest}->(@_);
810 sub _add_free_blist_sector { shift->_add_free_sector( 0, @_ ) }
811 sub _add_free_data_sector { shift->_add_free_sector( 1, @_ ) }
812 sub _add_free_index_sector { shift->_add_free_sector( 2, @_ ) }
814 sub _add_free_sector {
816 my ($multiple, $offset, $size) = @_;
818 my $chains_offset = $multiple * $self->byte_size;
820 my $storage = $self->storage;
822 # Increment staleness.
823 # XXX Can this increment+modulo be done by "&= 0x1" ?
824 my $staleness = unpack( $StP{$STALE_SIZE}, $storage->read_at( $offset + SIG_SIZE, $STALE_SIZE ) );
825 $staleness = ($staleness + 1 ) % ( 2 ** ( 8 * $STALE_SIZE ) );
826 $storage->print_at( $offset + SIG_SIZE, pack( $StP{$STALE_SIZE}, $staleness ) );
828 my $old_head = $storage->read_at( $self->chains_loc + $chains_offset, $self->byte_size );
830 $storage->print_at( $self->chains_loc + $chains_offset,
831 pack( $StP{$self->byte_size}, $offset ),
834 # Record the old head in the new sector after the signature and staleness counter
835 $storage->print_at( $offset + SIG_SIZE + $STALE_SIZE, $old_head );
838 sub _request_blist_sector { shift->_request_sector( 0, @_ ) }
839 sub _request_data_sector { shift->_request_sector( 1, @_ ) }
840 sub _request_index_sector { shift->_request_sector( 2, @_ ) }
842 sub _request_sector {
844 my ($multiple, $size) = @_;
846 my $chains_offset = $multiple * $self->byte_size;
848 my $old_head = $self->storage->read_at( $self->chains_loc + $chains_offset, $self->byte_size );
849 my $loc = unpack( $StP{$self->byte_size}, $old_head );
851 # We don't have any free sectors of the right size, so allocate a new one.
853 my $offset = $self->storage->request_space( $size );
855 # Zero out the new sector. This also guarantees correct increases
857 $self->storage->print_at( $offset, chr(0) x $size );
862 # Read the new head after the signature and the staleness counter
863 my $new_head = $self->storage->read_at( $loc + SIG_SIZE + $STALE_SIZE, $self->byte_size );
864 $self->storage->print_at( $self->chains_loc + $chains_offset, $new_head );
865 $self->storage->print_at(
866 $loc + SIG_SIZE + $STALE_SIZE,
867 pack( $StP{$self->byte_size}, 0 ),
873 ################################################################################
875 sub storage { $_[0]{storage} }
876 sub byte_size { $_[0]{byte_size} }
877 sub hash_size { $_[0]{hash_size} }
878 sub hash_chars { $_[0]{hash_chars} }
879 sub num_txns { $_[0]{num_txns} }
880 sub max_buckets { $_[0]{max_buckets} }
881 sub blank_md5 { chr(0) x $_[0]->hash_size }
882 sub data_sector_size { $_[0]{data_sector_size} }
884 # This is a calculated value
885 sub txn_bitfield_len {
887 unless ( exists $self->{txn_bitfield_len} ) {
888 my $temp = ($self->num_txns) / 8;
889 if ( $temp > int( $temp ) ) {
890 $temp = int( $temp ) + 1;
892 $self->{txn_bitfield_len} = $temp;
894 return $self->{txn_bitfield_len};
897 sub trans_id { $_[0]{trans_id} }
898 sub set_trans_id { $_[0]{trans_id} = $_[1] }
900 sub trans_loc { $_[0]{trans_loc} }
901 sub set_trans_loc { $_[0]{trans_loc} = $_[1] }
903 sub chains_loc { $_[0]{chains_loc} }
904 sub set_chains_loc { $_[0]{chains_loc} = $_[1] }
906 sub cache { $_[0]{cache} ||= {} }
907 sub clear_cache { %{$_[0]->cache} = () }
913 my $spot = $self->_read_file_header();
922 'D' => $self->data_sector_size,
923 'B' => DBM::Deep::Engine::Sector::BucketList->new({engine=>$self,offset=>1})->size,
924 'I' => DBM::Deep::Engine::Sector::Index->new({engine=>$self,offset=>1})->size,
930 $return .= "NumTxns: " . $self->num_txns . $/;
932 # Read the free sector chains
934 foreach my $multiple ( 0 .. 2 ) {
935 $return .= "Chains($types{$multiple}):";
936 my $old_loc = $self->chains_loc + $multiple * $self->byte_size;
939 $StP{$self->byte_size},
940 $self->storage->read_at( $old_loc, $self->byte_size ),
943 # We're now out of free sectors of this kind.
948 $sectors{ $types{$multiple} }{ $loc } = undef;
949 $old_loc = $loc + SIG_SIZE + $STALE_SIZE;
956 while ( $spot < $self->storage->{end} ) {
957 # Read each sector in order.
958 my $sector = $self->_load_sector( $spot );
960 # Find it in the free-sectors that were found already
961 foreach my $type ( keys %sectors ) {
962 if ( exists $sectors{$type}{$spot} ) {
963 my $size = $sizes{$type};
964 $return .= sprintf "%08d: %s %04d\n", $spot, 'F' . $type, $size;
970 die "********\n$return\nDidn't find free sector for $spot in chains\n********\n";
973 $return .= sprintf "%08d: %s %04d", $spot, $sector->type, $sector->size;
974 if ( $sector->type eq 'D' ) {
975 $return .= ' ' . $sector->data;
977 elsif ( $sector->type eq 'A' || $sector->type eq 'H' ) {
978 $return .= ' REF: ' . $sector->get_refcount;
980 elsif ( $sector->type eq 'B' ) {
981 foreach my $bucket ( $sector->chopped_up ) {
983 $return .= sprintf "%08d", unpack($StP{$self->byte_size},
984 substr( $bucket->[-1], $self->hash_size, $self->byte_size),
986 my $l = unpack( $StP{$self->byte_size},
987 substr( $bucket->[-1],
988 $self->hash_size + $self->byte_size,
992 $return .= sprintf " %08d", $l;
993 foreach my $txn ( 0 .. $self->num_txns - 2 ) {
994 my $l = unpack( $StP{$self->byte_size},
995 substr( $bucket->[-1],
996 $self->hash_size + 2 * $self->byte_size + $txn * ($self->byte_size + $STALE_SIZE),
1000 $return .= sprintf " %08d", $l;
1006 $spot += $sector->size;