use 5.006_000;
use strict;
-use warnings;
+use warnings FATAL => 'all';
our $VERSION = q(1.0013);
use 5.006_000;
use strict;
-use warnings;
-
-our $VERSION = q(1.0013);
+use warnings FATAL => 'all';
# This is to allow DBM::Deep::Array to handle negative indices on
# its own. Otherwise, Perl would intercept the call to negative
use 5.006_000;
use strict;
-use warnings;
+use warnings FATAL => 'all';
-our $VERSION = q(1.0013);
+use DBM::Deep::Engine::Sector::BucketList;
+use DBM::Deep::Engine::Sector::Index;
+use DBM::Deep::Engine::Sector::Null;
+use DBM::Deep::Engine::Sector::Reference;
+use DBM::Deep::Engine::Sector::Scalar;
+use DBM::Deep::Iterator;
# Never import symbols into our namespace. We are a class, not a library.
# -RobK, 2008-05-27
sub SIG_FREE () { 'F' }
sub SIG_SIZE () { 1 }
-my $STALE_SIZE = 2;
+our $STALE_SIZE = 2;
# Please refer to the pack() documentation for further information
my %StP = (
4 => 'N', # Unsigned long in "network" (big-endian) order
8 => 'Q', # Usigned quad (no order specified, presumably machine-dependent)
);
+sub StP { $StP{$_[1]} }
################################################################################
return $return;
}
-################################################################################
-
-package DBM::Deep::Iterator;
-
-sub new {
- my $class = shift;
- my ($args) = @_;
-
- my $self = bless {
- breadcrumbs => [],
- engine => $args->{engine},
- base_offset => $args->{base_offset},
- }, $class;
-
- Scalar::Util::weaken( $self->{engine} );
-
- return $self;
-}
-
-sub reset { $_[0]{breadcrumbs} = [] }
-
-sub get_sector_iterator {
- my $self = shift;
- my ($loc) = @_;
-
- my $sector = $self->{engine}->_load_sector( $loc )
- or return;
-
- if ( $sector->isa( 'DBM::Deep::Engine::Sector::Index' ) ) {
- return DBM::Deep::Iterator::Index->new({
- iterator => $self,
- sector => $sector,
- });
- }
- elsif ( $sector->isa( 'DBM::Deep::Engine::Sector::BucketList' ) ) {
- return DBM::Deep::Iterator::BucketList->new({
- iterator => $self,
- sector => $sector,
- });
- }
-
- DBM::Deep->_throw_error( "get_sector_iterator(): Why did $loc make a $sector?" );
-}
-
-sub get_next_key {
- my $self = shift;
- my ($obj) = @_;
-
- my $crumbs = $self->{breadcrumbs};
- my $e = $self->{engine};
-
- unless ( @$crumbs ) {
- # This will be a Reference sector
- my $sector = $e->_load_sector( $self->{base_offset} )
- # If no sector is found, thist must have been deleted from under us.
- or return;
-
- if ( $sector->staleness != $obj->_staleness ) {
- return;
- }
-
- my $loc = $sector->get_blist_loc
- or return;
-
- push @$crumbs, $self->get_sector_iterator( $loc );
- }
-
- FIND_NEXT_KEY: {
- # We're at the end.
- unless ( @$crumbs ) {
- $self->reset;
- return;
- }
-
- my $iterator = $crumbs->[-1];
-
- # This level is done.
- if ( $iterator->at_end ) {
- pop @$crumbs;
- redo FIND_NEXT_KEY;
- }
-
- if ( $iterator->isa( 'DBM::Deep::Iterator::Index' ) ) {
- # If we don't have any more, it will be caught at the
- # prior check.
- if ( my $next = $iterator->get_next_iterator ) {
- push @$crumbs, $next;
- }
- redo FIND_NEXT_KEY;
- }
-
- unless ( $iterator->isa( 'DBM::Deep::Iterator::BucketList' ) ) {
- DBM::Deep->_throw_error(
- "Should have a bucketlist iterator here - instead have $iterator"
- );
- }
-
- # At this point, we have a BucketList iterator
- my $key = $iterator->get_next_key;
- if ( defined $key ) {
- return $key;
- }
- #XXX else { $iterator->set_to_end() } ?
-
- # We hit the end of the bucketlist iterator, so redo
- redo FIND_NEXT_KEY;
- }
-
- DBM::Deep->_throw_error( "get_next_key(): How did we get here?" );
-}
-
-package DBM::Deep::Iterator::Index;
-
-sub new {
- my $self = bless $_[1] => $_[0];
- $self->{curr_index} = 0;
- return $self;
-}
-
-sub at_end {
- my $self = shift;
- return $self->{curr_index} >= $self->{iterator}{engine}->hash_chars;
-}
-
-sub get_next_iterator {
- my $self = shift;
-
- my $loc;
- while ( !$loc ) {
- return if $self->at_end;
- $loc = $self->{sector}->get_entry( $self->{curr_index}++ );
- }
-
- return $self->{iterator}->get_sector_iterator( $loc );
-}
-
-package DBM::Deep::Iterator::BucketList;
-
-sub new {
- my $self = bless $_[1] => $_[0];
- $self->{curr_index} = 0;
- return $self;
-}
-
-sub at_end {
- my $self = shift;
- return $self->{curr_index} >= $self->{iterator}{engine}->max_buckets;
-}
-
-sub get_next_key {
- my $self = shift;
-
- return if $self->at_end;
-
- my $idx = $self->{curr_index}++;
-
- my $data_loc = $self->{sector}->get_data_location_for({
- allow_head => 1,
- idx => $idx,
- }) or return;
-
- #XXX Do we want to add corruption checks here?
- return $self->{sector}->get_key_for( $idx )->data;
-}
-
-package DBM::Deep::Engine::Sector;
-
-sub new {
- my $self = bless $_[1], $_[0];
- Scalar::Util::weaken( $self->{engine} );
- $self->_init;
- return $self;
-}
-
-#sub _init {}
-#sub clone { DBM::Deep->_throw_error( "Must be implemented in the child class" ); }
-
-sub engine { $_[0]{engine} }
-sub offset { $_[0]{offset} }
-sub type { $_[0]{type} }
-
-sub base_size {
- my $self = shift;
- return $self->engine->SIG_SIZE + $STALE_SIZE;
-}
-
-sub free {
- my $self = shift;
-
- my $e = $self->engine;
-
- $e->storage->print_at( $self->offset, $e->SIG_FREE );
- # Skip staleness counter
- $e->storage->print_at( $self->offset + $self->base_size,
- chr(0) x ($self->size - $self->base_size),
- );
-
- my $free_meth = $self->free_meth;
- $e->$free_meth( $self->offset, $self->size );
-
- return;
-}
-
-package DBM::Deep::Engine::Sector::Data;
-
-our @ISA = qw( DBM::Deep::Engine::Sector );
-
-# This is in bytes
-sub size { $_[0]{engine}->data_sector_size }
-sub free_meth { return '_add_free_data_sector' }
-
-sub clone {
- my $self = shift;
- return ref($self)->new({
- engine => $self->engine,
- type => $self->type,
- data => $self->data,
- });
-}
-
-package DBM::Deep::Engine::Sector::Scalar;
-
-our @ISA = qw( DBM::Deep::Engine::Sector::Data );
-
-sub free {
- my $self = shift;
-
- my $chain_loc = $self->chain_loc;
-
- $self->SUPER::free();
-
- if ( $chain_loc ) {
- $self->engine->_load_sector( $chain_loc )->free;
- }
-
- return;
-}
-
-sub type { $_[0]{engine}->SIG_DATA }
-sub _init {
- my $self = shift;
-
- my $engine = $self->engine;
-
- unless ( $self->offset ) {
- my $data_section = $self->size - $self->base_size - $engine->byte_size - 1;
-
- $self->{offset} = $engine->_request_data_sector( $self->size );
-
- my $data = delete $self->{data};
- my $dlen = length $data;
- my $continue = 1;
- my $curr_offset = $self->offset;
- while ( $continue ) {
-
- my $next_offset = 0;
-
- my ($leftover, $this_len, $chunk);
- if ( $dlen > $data_section ) {
- $leftover = 0;
- $this_len = $data_section;
- $chunk = substr( $data, 0, $this_len );
-
- $dlen -= $data_section;
- $next_offset = $engine->_request_data_sector( $self->size );
- $data = substr( $data, $this_len );
- }
- else {
- $leftover = $data_section - $dlen;
- $this_len = $dlen;
- $chunk = $data;
-
- $continue = 0;
- }
-
- $engine->storage->print_at( $curr_offset, $self->type ); # Sector type
- # Skip staleness
- $engine->storage->print_at( $curr_offset + $self->base_size,
- pack( $StP{$engine->byte_size}, $next_offset ), # Chain loc
- pack( $StP{1}, $this_len ), # Data length
- $chunk, # Data to be stored in this sector
- chr(0) x $leftover, # Zero-fill the rest
- );
-
- $curr_offset = $next_offset;
- }
-
- return;
- }
-}
-
-sub data_length {
- my $self = shift;
-
- my $buffer = $self->engine->storage->read_at(
- $self->offset + $self->base_size + $self->engine->byte_size, 1
- );
-
- return unpack( $StP{1}, $buffer );
-}
-
-sub chain_loc {
- my $self = shift;
- return unpack(
- $StP{$self->engine->byte_size},
- $self->engine->storage->read_at(
- $self->offset + $self->base_size,
- $self->engine->byte_size,
- ),
- );
-}
-
-sub data {
- my $self = shift;
-# my ($args) = @_;
-# $args ||= {};
-
- my $data;
- while ( 1 ) {
- my $chain_loc = $self->chain_loc;
-
- $data .= $self->engine->storage->read_at(
- $self->offset + $self->base_size + $self->engine->byte_size + 1, $self->data_length,
- );
-
- last unless $chain_loc;
-
- $self = $self->engine->_load_sector( $chain_loc );
- }
-
- return $data;
-}
-
-package DBM::Deep::Engine::Sector::Null;
-
-our @ISA = qw( DBM::Deep::Engine::Sector::Data );
-
-sub type { $_[0]{engine}->SIG_NULL }
-sub data_length { 0 }
-sub data { return }
-
-sub _init {
- my $self = shift;
-
- my $engine = $self->engine;
-
- unless ( $self->offset ) {
- my $leftover = $self->size - $self->base_size - 1 * $engine->byte_size - 1;
-
- $self->{offset} = $engine->_request_data_sector( $self->size );
- $engine->storage->print_at( $self->offset, $self->type ); # Sector type
- # Skip staleness counter
- $engine->storage->print_at( $self->offset + $self->base_size,
- pack( $StP{$engine->byte_size}, 0 ), # Chain loc
- pack( $StP{1}, $self->data_length ), # Data length
- chr(0) x $leftover, # Zero-fill the rest
- );
-
- return;
- }
-}
-
-package DBM::Deep::Engine::Sector::Reference;
-
-our @ISA = qw( DBM::Deep::Engine::Sector::Data );
-
-sub _init {
- my $self = shift;
-
- my $e = $self->engine;
-
- unless ( $self->offset ) {
- my $classname = Scalar::Util::blessed( delete $self->{data} );
- my $leftover = $self->size - $self->base_size - 3 * $e->byte_size;
-
- my $class_offset = 0;
- if ( defined $classname ) {
- my $class_sector = DBM::Deep::Engine::Sector::Scalar->new({
- engine => $e,
- data => $classname,
- });
- $class_offset = $class_sector->offset;
- }
-
- $self->{offset} = $e->_request_data_sector( $self->size );
- $e->storage->print_at( $self->offset, $self->type ); # Sector type
- # Skip staleness counter
- $e->storage->print_at( $self->offset + $self->base_size,
- pack( $StP{$e->byte_size}, 0 ), # Index/BList loc
- pack( $StP{$e->byte_size}, $class_offset ), # Classname loc
- pack( $StP{$e->byte_size}, 1 ), # Initial refcount
- chr(0) x $leftover, # Zero-fill the rest
- );
- }
- else {
- $self->{type} = $e->storage->read_at( $self->offset, 1 );
- }
-
- $self->{staleness} = unpack(
- $StP{$STALE_SIZE},
- $e->storage->read_at( $self->offset + $e->SIG_SIZE, $STALE_SIZE ),
- );
-
- return;
-}
-
-sub staleness { $_[0]{staleness} }
-
-sub get_data_location_for {
- my $self = shift;
- my ($args) = @_;
-
- # Assume that the head is not allowed unless otherwise specified.
- $args->{allow_head} = 0 unless exists $args->{allow_head};
-
- # Assume we don't create a new blist location unless otherwise specified.
- $args->{create} = 0 unless exists $args->{create};
-
- my $blist = $self->get_bucket_list({
- key_md5 => $args->{key_md5},
- key => $args->{key},
- create => $args->{create},
- });
- return unless $blist && $blist->{found};
-
- # At this point, $blist knows where the md5 is. What it -doesn't- know yet
- # is whether or not this transaction has this key. That's part of the next
- # function call.
- my $location = $blist->get_data_location_for({
- allow_head => $args->{allow_head},
- }) or return;
-
- return $location;
-}
-
-sub get_data_for {
- my $self = shift;
- my ($args) = @_;
-
- my $location = $self->get_data_location_for( $args )
- or return;
-
- return $self->engine->_load_sector( $location );
-}
-
-sub write_data {
- my $self = shift;
- my ($args) = @_;
-
- my $blist = $self->get_bucket_list({
- key_md5 => $args->{key_md5},
- key => $args->{key},
- create => 1,
- }) or DBM::Deep->_throw_error( "How did write_data fail (no blist)?!" );
-
- # Handle any transactional bookkeeping.
- if ( $self->engine->trans_id ) {
- if ( ! $blist->has_md5 ) {
- $blist->mark_deleted({
- trans_id => 0,
- });
- }
- }
- else {
- my @trans_ids = $self->engine->get_running_txn_ids;
- if ( $blist->has_md5 ) {
- if ( @trans_ids ) {
- my $old_value = $blist->get_data_for;
- foreach my $other_trans_id ( @trans_ids ) {
- next if $blist->get_data_location_for({
- trans_id => $other_trans_id,
- allow_head => 0,
- });
- $blist->write_md5({
- trans_id => $other_trans_id,
- key => $args->{key},
- key_md5 => $args->{key_md5},
- value => $old_value->clone,
- });
- }
- }
- }
- else {
- if ( @trans_ids ) {
- foreach my $other_trans_id ( @trans_ids ) {
- #XXX This doesn't seem to possible to ever happen . . .
- next if $blist->get_data_location_for({ trans_id => $other_trans_id, allow_head => 0 });
- $blist->mark_deleted({
- trans_id => $other_trans_id,
- });
- }
- }
- }
- }
-
- #XXX Is this safe to do transactionally?
- # Free the place we're about to write to.
- if ( $blist->get_data_location_for({ allow_head => 0 }) ) {
- $blist->get_data_for({ allow_head => 0 })->free;
- }
-
- $blist->write_md5({
- key => $args->{key},
- key_md5 => $args->{key_md5},
- value => $args->{value},
- });
-}
-
-sub delete_key {
- my $self = shift;
- my ($args) = @_;
-
- # XXX What should happen if this fails?
- my $blist = $self->get_bucket_list({
- key_md5 => $args->{key_md5},
- }) or DBM::Deep->_throw_error( "How did delete_key fail (no blist)?!" );
-
- # Save the location so that we can free the data
- my $location = $blist->get_data_location_for({
- allow_head => 0,
- });
- my $old_value = $location && $self->engine->_load_sector( $location );
-
- my @trans_ids = $self->engine->get_running_txn_ids;
-
- # If we're the HEAD and there are running txns, then we need to clone this value to the other
- # transactions to preserve Isolation.
- if ( $self->engine->trans_id == 0 ) {
- if ( @trans_ids ) {
- foreach my $other_trans_id ( @trans_ids ) {
- next if $blist->get_data_location_for({ trans_id => $other_trans_id, allow_head => 0 });
- $blist->write_md5({
- trans_id => $other_trans_id,
- key => $args->{key},
- key_md5 => $args->{key_md5},
- value => $old_value->clone,
- });
- }
- }
- }
-
- my $data;
- if ( @trans_ids ) {
- $blist->mark_deleted( $args );
-
- if ( $old_value ) {
- $data = $old_value->data({ export => 1 });
- $old_value->free;
- }
- }
- else {
- $data = $blist->delete_md5( $args );
- }
-
- return $data;
-}
-
-sub get_blist_loc {
- my $self = shift;
-
- my $e = $self->engine;
- my $blist_loc = $e->storage->read_at( $self->offset + $self->base_size, $e->byte_size );
- return unpack( $StP{$e->byte_size}, $blist_loc );
-}
-
-sub get_bucket_list {
- my $self = shift;
- my ($args) = @_;
- $args ||= {};
-
- # XXX Add in check here for recycling?
-
- my $engine = $self->engine;
-
- my $blist_loc = $self->get_blist_loc;
-
- # There's no index or blist yet
- unless ( $blist_loc ) {
- return unless $args->{create};
-
- my $blist = DBM::Deep::Engine::Sector::BucketList->new({
- engine => $engine,
- key_md5 => $args->{key_md5},
- });
-
- $engine->storage->print_at( $self->offset + $self->base_size,
- pack( $StP{$engine->byte_size}, $blist->offset ),
- );
-
- return $blist;
- }
-
- my $sector = $engine->_load_sector( $blist_loc )
- or DBM::Deep->_throw_error( "Cannot read sector at $blist_loc in get_bucket_list()" );
- my $i = 0;
- my $last_sector = undef;
- while ( $sector->isa( 'DBM::Deep::Engine::Sector::Index' ) ) {
- $blist_loc = $sector->get_entry( ord( substr( $args->{key_md5}, $i++, 1 ) ) );
- $last_sector = $sector;
- if ( $blist_loc ) {
- $sector = $engine->_load_sector( $blist_loc )
- or DBM::Deep->_throw_error( "Cannot read sector at $blist_loc in get_bucket_list()" );
- }
- else {
- $sector = undef;
- last;
- }
- }
-
- # This means we went through the Index sector(s) and found an empty slot
- unless ( $sector ) {
- return unless $args->{create};
-
- DBM::Deep->_throw_error( "No last_sector when attempting to build a new entry" )
- unless $last_sector;
-
- my $blist = DBM::Deep::Engine::Sector::BucketList->new({
- engine => $engine,
- key_md5 => $args->{key_md5},
- });
-
- $last_sector->set_entry( ord( substr( $args->{key_md5}, $i - 1, 1 ) ) => $blist->offset );
-
- return $blist;
- }
-
- $sector->find_md5( $args->{key_md5} );
-
- # See whether or not we need to reindex the bucketlist
- # Yes, the double-braces are there for a reason. if() doesn't create a redo-able block,
- # so we have to create a bare block within the if() for redo-purposes. Patch and idea
- # submitted by sprout@cpan.org. -RobK, 2008-01-09
- if ( !$sector->has_md5 && $args->{create} && $sector->{idx} == -1 ) {{
- my $redo;
-
- my $new_index = DBM::Deep::Engine::Sector::Index->new({
- engine => $engine,
- });
-
- my %blist_cache;
- #XXX q.v. the comments for this function.
- foreach my $entry ( $sector->chopped_up ) {
- my ($spot, $md5) = @{$entry};
- my $idx = ord( substr( $md5, $i, 1 ) );
-
- # XXX This is inefficient
- my $blist = $blist_cache{$idx}
- ||= DBM::Deep::Engine::Sector::BucketList->new({
- engine => $engine,
- });
-
- $new_index->set_entry( $idx => $blist->offset );
-
- my $new_spot = $blist->write_at_next_open( $md5 );
- $engine->reindex_entry( $spot => $new_spot );
- }
-
- # Handle the new item separately.
- {
- my $idx = ord( substr( $args->{key_md5}, $i, 1 ) );
-
- # If all the previous blist's items have been thrown into one
- # blist and the new item belongs in there too, we need
- # another index.
- if ( keys %blist_cache == 1 and each %blist_cache == $idx ) {
- ++$i, ++$redo;
- } else {
- my $blist = $blist_cache{$idx}
- ||= DBM::Deep::Engine::Sector::BucketList->new({
- engine => $engine,
- });
-
- $new_index->set_entry( $idx => $blist->offset );
-
- #XXX THIS IS HACKY!
- $blist->find_md5( $args->{key_md5} );
- $blist->write_md5({
- key => $args->{key},
- key_md5 => $args->{key_md5},
- value => DBM::Deep::Engine::Sector::Null->new({
- engine => $engine,
- data => undef,
- }),
- });
- }
-# my $blist = $blist_cache{$idx}
-# ||= DBM::Deep::Engine::Sector::BucketList->new({
-# engine => $engine,
-# });
-#
-# $new_index->set_entry( $idx => $blist->offset );
-#
-# #XXX THIS IS HACKY!
-# $blist->find_md5( $args->{key_md5} );
-# $blist->write_md5({
-# key => $args->{key},
-# key_md5 => $args->{key_md5},
-# value => DBM::Deep::Engine::Sector::Null->new({
-# engine => $engine,
-# data => undef,
-# }),
-# });
- }
-
- if ( $last_sector ) {
- $last_sector->set_entry(
- ord( substr( $args->{key_md5}, $i - 1, 1 ) ),
- $new_index->offset,
- );
- } else {
- $engine->storage->print_at( $self->offset + $self->base_size,
- pack( $StP{$engine->byte_size}, $new_index->offset ),
- );
- }
-
- $sector->clear;
- $sector->free;
-
- if ( $redo ) {
- (undef, $sector) = %blist_cache;
- $last_sector = $new_index;
- redo;
- }
-
- $sector = $blist_cache{ ord( substr( $args->{key_md5}, $i, 1 ) ) };
- $sector->find_md5( $args->{key_md5} );
- }}
-
- return $sector;
-}
-
-sub get_class_offset {
- my $self = shift;
-
- my $e = $self->engine;
- return unpack(
- $StP{$e->byte_size},
- $e->storage->read_at(
- $self->offset + $self->base_size + 1 * $e->byte_size, $e->byte_size,
- ),
- );
-}
-
-sub get_classname {
- my $self = shift;
-
- my $class_offset = $self->get_class_offset;
-
- return unless $class_offset;
-
- return $self->engine->_load_sector( $class_offset )->data;
-}
-
-sub data {
- my $self = shift;
- my ($args) = @_;
- $args ||= {};
-
- my $obj;
- unless ( $obj = $self->engine->cache->{ $self->offset } ) {
- $obj = DBM::Deep->new({
- type => $self->type,
- base_offset => $self->offset,
- staleness => $self->staleness,
- storage => $self->engine->storage,
- engine => $self->engine,
- });
-
- if ( $self->engine->storage->{autobless} ) {
- my $classname = $self->get_classname;
- if ( defined $classname ) {
- bless $obj, $classname;
- }
- }
-
- $self->engine->cache->{$self->offset} = $obj;
- }
-
- # We're not exporting, so just return.
- unless ( $args->{export} ) {
- return $obj;
- }
-
- # We shouldn't export if this is still referred to.
- if ( $self->get_refcount > 1 ) {
- return $obj;
- }
-
- return $obj->export;
-}
-
-sub free {
- my $self = shift;
-
- # We're not ready to be removed yet.
- if ( $self->decrement_refcount > 0 ) {
- return;
- }
-
- # Rebless the object into DBM::Deep::Null.
- eval { %{ $self->engine->cache->{ $self->offset } } = (); };
- eval { @{ $self->engine->cache->{ $self->offset } } = (); };
- bless $self->engine->cache->{ $self->offset }, 'DBM::Deep::Null';
- delete $self->engine->cache->{ $self->offset };
-
- my $blist_loc = $self->get_blist_loc;
- $self->engine->_load_sector( $blist_loc )->free if $blist_loc;
-
- my $class_loc = $self->get_class_offset;
- $self->engine->_load_sector( $class_loc )->free if $class_loc;
-
- $self->SUPER::free();
-}
-
-sub increment_refcount {
- my $self = shift;
-
- my $refcount = $self->get_refcount;
-
- $refcount++;
-
- $self->write_refcount( $refcount );
-
- return $refcount;
-}
-
-sub decrement_refcount {
- my $self = shift;
-
- my $refcount = $self->get_refcount;
-
- $refcount--;
-
- $self->write_refcount( $refcount );
-
- return $refcount;
-}
-
-sub get_refcount {
- my $self = shift;
-
- my $e = $self->engine;
- return unpack(
- $StP{$e->byte_size},
- $e->storage->read_at(
- $self->offset + $self->base_size + 2 * $e->byte_size, $e->byte_size,
- ),
- );
-}
-
-sub write_refcount {
- my $self = shift;
- my ($num) = @_;
-
- my $e = $self->engine;
- $e->storage->print_at(
- $self->offset + $self->base_size + 2 * $e->byte_size,
- pack( $StP{$e->byte_size}, $num ),
- );
-}
-
-package DBM::Deep::Engine::Sector::BucketList;
-
-our @ISA = qw( DBM::Deep::Engine::Sector );
-
-sub _init {
- my $self = shift;
-
- my $engine = $self->engine;
-
- unless ( $self->offset ) {
- my $leftover = $self->size - $self->base_size;
-
- $self->{offset} = $engine->_request_blist_sector( $self->size );
- $engine->storage->print_at( $self->offset, $engine->SIG_BLIST ); # Sector type
- # Skip staleness counter
- $engine->storage->print_at( $self->offset + $self->base_size,
- chr(0) x $leftover, # Zero-fill the data
- );
- }
-
- if ( $self->{key_md5} ) {
- $self->find_md5;
- }
-
- return $self;
-}
-
-sub clear {
- my $self = shift;
- $self->engine->storage->print_at( $self->offset + $self->base_size,
- chr(0) x ($self->size - $self->base_size), # Zero-fill the data
- );
-}
-
-sub size {
- my $self = shift;
- unless ( $self->{size} ) {
- my $e = $self->engine;
- # Base + numbuckets * bucketsize
- $self->{size} = $self->base_size + $e->max_buckets * $self->bucket_size;
- }
- return $self->{size};
-}
-
-sub free_meth { return '_add_free_blist_sector' }
-
-sub free {
- my $self = shift;
-
- my $e = $self->engine;
- foreach my $bucket ( $self->chopped_up ) {
- my $rest = $bucket->[-1];
-
- # Delete the keysector
- my $l = unpack( $StP{$e->byte_size}, substr( $rest, $e->hash_size, $e->byte_size ) );
- my $s = $e->_load_sector( $l ); $s->free if $s;
-
- # Delete the HEAD sector
- $l = unpack( $StP{$e->byte_size},
- substr( $rest,
- $e->hash_size + $e->byte_size,
- $e->byte_size,
- ),
- );
- $s = $e->_load_sector( $l ); $s->free if $s;
-
- foreach my $txn ( 0 .. $e->num_txns - 2 ) {
- my $l = unpack( $StP{$e->byte_size},
- substr( $rest,
- $e->hash_size + 2 * $e->byte_size + $txn * ($e->byte_size + $STALE_SIZE),
- $e->byte_size,
- ),
- );
- my $s = $e->_load_sector( $l ); $s->free if $s;
- }
- }
-
- $self->SUPER::free();
-}
-
-sub bucket_size {
- my $self = shift;
- unless ( $self->{bucket_size} ) {
- my $e = $self->engine;
- # Key + head (location) + transactions (location + staleness-counter)
- my $location_size = $e->byte_size + $e->byte_size + ($e->num_txns - 1) * ($e->byte_size + $STALE_SIZE);
- $self->{bucket_size} = $e->hash_size + $location_size;
- }
- return $self->{bucket_size};
-}
-
-# XXX This is such a poor hack. I need to rethink this code.
-sub chopped_up {
- my $self = shift;
-
- my $e = $self->engine;
-
- my @buckets;
- foreach my $idx ( 0 .. $e->max_buckets - 1 ) {
- my $spot = $self->offset + $self->base_size + $idx * $self->bucket_size;
- my $md5 = $e->storage->read_at( $spot, $e->hash_size );
-
- #XXX If we're chopping, why would we ever have the blank_md5?
- last if $md5 eq $e->blank_md5;
-
- my $rest = $e->storage->read_at( undef, $self->bucket_size - $e->hash_size );
- push @buckets, [ $spot, $md5 . $rest ];
- }
-
- return @buckets;
-}
-
-sub write_at_next_open {
- my $self = shift;
- my ($entry) = @_;
-
- #XXX This is such a hack!
- $self->{_next_open} = 0 unless exists $self->{_next_open};
-
- my $spot = $self->offset + $self->base_size + $self->{_next_open}++ * $self->bucket_size;
- $self->engine->storage->print_at( $spot, $entry );
-
- return $spot;
-}
-
-sub has_md5 {
- my $self = shift;
- unless ( exists $self->{found} ) {
- $self->find_md5;
- }
- return $self->{found};
-}
-
-sub find_md5 {
- my $self = shift;
-
- $self->{found} = undef;
- $self->{idx} = -1;
-
- if ( @_ ) {
- $self->{key_md5} = shift;
- }
-
- # If we don't have an MD5, then what are we supposed to do?
- unless ( exists $self->{key_md5} ) {
- DBM::Deep->_throw_error( "Cannot find_md5 without a key_md5 set" );
- }
-
- my $e = $self->engine;
- foreach my $idx ( 0 .. $e->max_buckets - 1 ) {
- my $potential = $e->storage->read_at(
- $self->offset + $self->base_size + $idx * $self->bucket_size, $e->hash_size,
- );
-
- if ( $potential eq $e->blank_md5 ) {
- $self->{idx} = $idx;
- return;
- }
-
- if ( $potential eq $self->{key_md5} ) {
- $self->{found} = 1;
- $self->{idx} = $idx;
- return;
- }
- }
-
- return;
-}
-
-sub write_md5 {
- my $self = shift;
- my ($args) = @_;
-
- DBM::Deep->_throw_error( "write_md5: no key" ) unless exists $args->{key};
- DBM::Deep->_throw_error( "write_md5: no key_md5" ) unless exists $args->{key_md5};
- DBM::Deep->_throw_error( "write_md5: no value" ) unless exists $args->{value};
-
- my $engine = $self->engine;
-
- $args->{trans_id} = $engine->trans_id unless exists $args->{trans_id};
-
- my $spot = $self->offset + $self->base_size + $self->{idx} * $self->bucket_size;
- $engine->add_entry( $args->{trans_id}, $spot );
-
- unless ($self->{found}) {
- my $key_sector = DBM::Deep::Engine::Sector::Scalar->new({
- engine => $engine,
- data => $args->{key},
- });
-
- $engine->storage->print_at( $spot,
- $args->{key_md5},
- pack( $StP{$engine->byte_size}, $key_sector->offset ),
- );
- }
-
- my $loc = $spot
- + $engine->hash_size
- + $engine->byte_size;
-
- if ( $args->{trans_id} ) {
- $loc += $engine->byte_size + ($args->{trans_id} - 1) * ( $engine->byte_size + $STALE_SIZE );
-
- $engine->storage->print_at( $loc,
- pack( $StP{$engine->byte_size}, $args->{value}->offset ),
- pack( $StP{$STALE_SIZE}, $engine->get_txn_staleness_counter( $args->{trans_id} ) ),
- );
- }
- else {
- $engine->storage->print_at( $loc,
- pack( $StP{$engine->byte_size}, $args->{value}->offset ),
- );
- }
-}
-
-sub mark_deleted {
- my $self = shift;
- my ($args) = @_;
- $args ||= {};
-
- my $engine = $self->engine;
-
- $args->{trans_id} = $engine->trans_id unless exists $args->{trans_id};
-
- my $spot = $self->offset + $self->base_size + $self->{idx} * $self->bucket_size;
- $engine->add_entry( $args->{trans_id}, $spot );
-
- my $loc = $spot
- + $engine->hash_size
- + $engine->byte_size;
-
- if ( $args->{trans_id} ) {
- $loc += $engine->byte_size + ($args->{trans_id} - 1) * ( $engine->byte_size + $STALE_SIZE );
-
- $engine->storage->print_at( $loc,
- pack( $StP{$engine->byte_size}, 1 ), # 1 is the marker for deleted
- pack( $StP{$STALE_SIZE}, $engine->get_txn_staleness_counter( $args->{trans_id} ) ),
- );
- }
- else {
- $engine->storage->print_at( $loc,
- pack( $StP{$engine->byte_size}, 1 ), # 1 is the marker for deleted
- );
- }
-
-}
-
-sub delete_md5 {
- my $self = shift;
- my ($args) = @_;
-
- my $engine = $self->engine;
- return undef unless $self->{found};
-
- # Save the location so that we can free the data
- my $location = $self->get_data_location_for({
- allow_head => 0,
- });
- my $key_sector = $self->get_key_for;
-
- my $spot = $self->offset + $self->base_size + $self->{idx} * $self->bucket_size;
- $engine->storage->print_at( $spot,
- $engine->storage->read_at(
- $spot + $self->bucket_size,
- $self->bucket_size * ( $engine->max_buckets - $self->{idx} - 1 ),
- ),
- chr(0) x $self->bucket_size,
- );
-
- $key_sector->free;
-
- my $data_sector = $self->engine->_load_sector( $location );
- my $data = $data_sector->data({ export => 1 });
- $data_sector->free;
-
- return $data;
-}
-
-sub get_data_location_for {
- my $self = shift;
- my ($args) = @_;
- $args ||= {};
-
- $args->{allow_head} = 0 unless exists $args->{allow_head};
- $args->{trans_id} = $self->engine->trans_id unless exists $args->{trans_id};
- $args->{idx} = $self->{idx} unless exists $args->{idx};
-
- my $e = $self->engine;
-
- my $spot = $self->offset + $self->base_size
- + $args->{idx} * $self->bucket_size
- + $e->hash_size
- + $e->byte_size;
-
- if ( $args->{trans_id} ) {
- $spot += $e->byte_size + ($args->{trans_id} - 1) * ( $e->byte_size + $STALE_SIZE );
- }
-
- my $buffer = $e->storage->read_at(
- $spot,
- $e->byte_size + $STALE_SIZE,
- );
- my ($loc, $staleness) = unpack( $StP{$e->byte_size} . ' ' . $StP{$STALE_SIZE}, $buffer );
-
- # XXX Merge the two if-clauses below
- if ( $args->{trans_id} ) {
- # We have found an entry that is old, so get rid of it
- if ( $staleness != (my $s = $e->get_txn_staleness_counter( $args->{trans_id} ) ) ) {
- $e->storage->print_at(
- $spot,
- pack( $StP{$e->byte_size} . ' ' . $StP{$STALE_SIZE}, (0) x 2 ),
- );
- $loc = 0;
- }
- }
-
- # If we're in a transaction and we never wrote to this location, try the
- # HEAD instead.
- if ( $args->{trans_id} && !$loc && $args->{allow_head} ) {
- return $self->get_data_location_for({
- trans_id => 0,
- allow_head => 1,
- idx => $args->{idx},
- });
- }
-
- return $loc <= 1 ? 0 : $loc;
-}
-
-sub get_data_for {
- my $self = shift;
- my ($args) = @_;
- $args ||= {};
-
- return unless $self->{found};
- my $location = $self->get_data_location_for({
- allow_head => $args->{allow_head},
- });
- return $self->engine->_load_sector( $location );
-}
-
-sub get_key_for {
- my $self = shift;
- my ($idx) = @_;
- $idx = $self->{idx} unless defined $idx;
-
- if ( $idx >= $self->engine->max_buckets ) {
- DBM::Deep->_throw_error( "get_key_for(): Attempting to retrieve $idx" );
- }
-
- my $location = $self->engine->storage->read_at(
- $self->offset + $self->base_size + $idx * $self->bucket_size + $self->engine->hash_size,
- $self->engine->byte_size,
- );
- $location = unpack( $StP{$self->engine->byte_size}, $location );
- DBM::Deep->_throw_error( "get_key_for: No location?" ) unless $location;
-
- return $self->engine->_load_sector( $location );
-}
-
-package DBM::Deep::Engine::Sector::Index;
-
-our @ISA = qw( DBM::Deep::Engine::Sector );
-
-sub _init {
- my $self = shift;
-
- my $engine = $self->engine;
-
- unless ( $self->offset ) {
- my $leftover = $self->size - $self->base_size;
-
- $self->{offset} = $engine->_request_index_sector( $self->size );
- $engine->storage->print_at( $self->offset, $engine->SIG_INDEX ); # Sector type
- # Skip staleness counter
- $engine->storage->print_at( $self->offset + $self->base_size,
- chr(0) x $leftover, # Zero-fill the rest
- );
- }
-
- return $self;
-}
-
-#XXX Change here
-sub size {
- my $self = shift;
- unless ( $self->{size} ) {
- my $e = $self->engine;
- $self->{size} = $self->base_size + $e->byte_size * $e->hash_chars;
- }
- return $self->{size};
-}
-
-sub free_meth { return '_add_free_index_sector' }
-
-sub free {
- my $self = shift;
- my $e = $self->engine;
-
- for my $i ( 0 .. $e->hash_chars - 1 ) {
- my $l = $self->get_entry( $i ) or next;
- $e->_load_sector( $l )->free;
- }
-
- $self->SUPER::free();
-}
-
-sub _loc_for {
- my $self = shift;
- my ($idx) = @_;
- return $self->offset + $self->base_size + $idx * $self->engine->byte_size;
-}
-
-sub get_entry {
- my $self = shift;
- my ($idx) = @_;
-
- my $e = $self->engine;
-
- DBM::Deep->_throw_error( "get_entry: Out of range ($idx)" )
- if $idx < 0 || $idx >= $e->hash_chars;
-
- return unpack(
- $StP{$e->byte_size},
- $e->storage->read_at( $self->_loc_for( $idx ), $e->byte_size ),
- );
-}
-
-sub set_entry {
- my $self = shift;
- my ($idx, $loc) = @_;
-
- my $e = $self->engine;
-
- DBM::Deep->_throw_error( "set_entry: Out of range ($idx)" )
- if $idx < 0 || $idx >= $e->hash_chars;
-
- $self->engine->storage->print_at(
- $self->_loc_for( $idx ),
- pack( $StP{$e->byte_size}, $loc ),
- );
-}
-
-# This was copied from MARCEL's Class::Null. However, I couldn't use it because
-# I need an undef value, not an implementation of the Null Class pattern.
-package DBM::Deep::Null;
-
-use overload
- 'bool' => sub { undef },
- '""' => sub { undef },
- '0+' => sub { undef },
- fallback => 1,
- nomethod => 'AUTOLOAD';
-
-sub AUTOLOAD { return; }
-
1;
__END__
--- /dev/null
+package DBM::Deep::Engine::Sector;
+
+use 5.006;
+
+use strict;
+use warnings FATAL => 'all';
+
+use Scalar::Util ();
+
+sub new {
+ my $self = bless $_[1], $_[0];
+ Scalar::Util::weaken( $self->{engine} );
+ $self->_init;
+ return $self;
+}
+
+#sub _init {}
+#sub clone { DBM::Deep->_throw_error( "Must be implemented in the child class" ); }
+
+sub engine { $_[0]{engine} }
+sub offset { $_[0]{offset} }
+sub type { $_[0]{type} }
+
+sub base_size {
+ my $self = shift;
+ no warnings 'once';
+ return $self->engine->SIG_SIZE + $DBM::Deep::Engine::STALE_SIZE;
+}
+
+sub free {
+ my $self = shift;
+
+ my $e = $self->engine;
+
+ $e->storage->print_at( $self->offset, $e->SIG_FREE );
+ # Skip staleness counter
+ $e->storage->print_at( $self->offset + $self->base_size,
+ chr(0) x ($self->size - $self->base_size),
+ );
+
+ my $free_meth = $self->free_meth;
+ $e->$free_meth( $self->offset, $self->size );
+
+ return;
+}
+
+1;
+__END__
--- /dev/null
+#TODO: Convert this to a string
+package DBM::Deep::Engine::Sector::BucketList;
+
+use 5.006;
+
+use strict;
+use warnings FATAL => 'all';
+
+use DBM::Deep::Engine::Sector;
+our @ISA = qw( DBM::Deep::Engine::Sector );
+
+sub _init {
+ my $self = shift;
+
+ my $engine = $self->engine;
+
+ unless ( $self->offset ) {
+ my $leftover = $self->size - $self->base_size;
+
+ $self->{offset} = $engine->_request_blist_sector( $self->size );
+ $engine->storage->print_at( $self->offset, $engine->SIG_BLIST ); # Sector type
+ # Skip staleness counter
+ $engine->storage->print_at( $self->offset + $self->base_size,
+ chr(0) x $leftover, # Zero-fill the data
+ );
+ }
+
+ if ( $self->{key_md5} ) {
+ $self->find_md5;
+ }
+
+ return $self;
+}
+
+sub clear {
+ my $self = shift;
+ $self->engine->storage->print_at( $self->offset + $self->base_size,
+ chr(0) x ($self->size - $self->base_size), # Zero-fill the data
+ );
+}
+
+sub size {
+ my $self = shift;
+ unless ( $self->{size} ) {
+ my $e = $self->engine;
+ # Base + numbuckets * bucketsize
+ $self->{size} = $self->base_size + $e->max_buckets * $self->bucket_size;
+ }
+ return $self->{size};
+}
+
+sub free_meth { return '_add_free_blist_sector' }
+
+sub free {
+ my $self = shift;
+
+ my $e = $self->engine;
+ foreach my $bucket ( $self->chopped_up ) {
+ my $rest = $bucket->[-1];
+
+ # Delete the keysector
+ my $l = unpack( $e->StP($e->byte_size), substr( $rest, $e->hash_size, $e->byte_size ) );
+ my $s = $e->_load_sector( $l ); $s->free if $s;
+
+ # Delete the HEAD sector
+ $l = unpack( $e->StP($e->byte_size),
+ substr( $rest,
+ $e->hash_size + $e->byte_size,
+ $e->byte_size,
+ ),
+ );
+ $s = $e->_load_sector( $l ); $s->free if $s;
+
+ foreach my $txn ( 0 .. $e->num_txns - 2 ) {
+ my $l = unpack( $e->StP($e->byte_size),
+ substr( $rest,
+ $e->hash_size + 2 * $e->byte_size + $txn * ($e->byte_size + $DBM::Deep::Engine::STALE_SIZE),
+ $e->byte_size,
+ ),
+ );
+ my $s = $e->_load_sector( $l ); $s->free if $s;
+ }
+ }
+
+ $self->SUPER::free();
+}
+
+sub bucket_size {
+ my $self = shift;
+ unless ( $self->{bucket_size} ) {
+ my $e = $self->engine;
+ # Key + head (location) + transactions (location + staleness-counter)
+ my $location_size = $e->byte_size + $e->byte_size + ($e->num_txns - 1) * ($e->byte_size + $DBM::Deep::Engine::STALE_SIZE);
+ $self->{bucket_size} = $e->hash_size + $location_size;
+ }
+ return $self->{bucket_size};
+}
+
+# XXX This is such a poor hack. I need to rethink this code.
+sub chopped_up {
+ my $self = shift;
+
+ my $e = $self->engine;
+
+ my @buckets;
+ foreach my $idx ( 0 .. $e->max_buckets - 1 ) {
+ my $spot = $self->offset + $self->base_size + $idx * $self->bucket_size;
+ my $md5 = $e->storage->read_at( $spot, $e->hash_size );
+
+ #XXX If we're chopping, why would we ever have the blank_md5?
+ last if $md5 eq $e->blank_md5;
+
+ my $rest = $e->storage->read_at( undef, $self->bucket_size - $e->hash_size );
+ push @buckets, [ $spot, $md5 . $rest ];
+ }
+
+ return @buckets;
+}
+
+sub write_at_next_open {
+ my $self = shift;
+ my ($entry) = @_;
+
+ #XXX This is such a hack!
+ $self->{_next_open} = 0 unless exists $self->{_next_open};
+
+ my $spot = $self->offset + $self->base_size + $self->{_next_open}++ * $self->bucket_size;
+ $self->engine->storage->print_at( $spot, $entry );
+
+ return $spot;
+}
+
+sub has_md5 {
+ my $self = shift;
+ unless ( exists $self->{found} ) {
+ $self->find_md5;
+ }
+ return $self->{found};
+}
+
+sub find_md5 {
+ my $self = shift;
+
+ $self->{found} = undef;
+ $self->{idx} = -1;
+
+ if ( @_ ) {
+ $self->{key_md5} = shift;
+ }
+
+ # If we don't have an MD5, then what are we supposed to do?
+ unless ( exists $self->{key_md5} ) {
+ DBM::Deep->_throw_error( "Cannot find_md5 without a key_md5 set" );
+ }
+
+ my $e = $self->engine;
+ foreach my $idx ( 0 .. $e->max_buckets - 1 ) {
+ my $potential = $e->storage->read_at(
+ $self->offset + $self->base_size + $idx * $self->bucket_size, $e->hash_size,
+ );
+
+ if ( $potential eq $e->blank_md5 ) {
+ $self->{idx} = $idx;
+ return;
+ }
+
+ if ( $potential eq $self->{key_md5} ) {
+ $self->{found} = 1;
+ $self->{idx} = $idx;
+ return;
+ }
+ }
+
+ return;
+}
+
+sub write_md5 {
+ my $self = shift;
+ my ($args) = @_;
+
+ DBM::Deep->_throw_error( "write_md5: no key" ) unless exists $args->{key};
+ DBM::Deep->_throw_error( "write_md5: no key_md5" ) unless exists $args->{key_md5};
+ DBM::Deep->_throw_error( "write_md5: no value" ) unless exists $args->{value};
+
+ my $engine = $self->engine;
+
+ $args->{trans_id} = $engine->trans_id unless exists $args->{trans_id};
+
+ my $spot = $self->offset + $self->base_size + $self->{idx} * $self->bucket_size;
+ $engine->add_entry( $args->{trans_id}, $spot );
+
+ unless ($self->{found}) {
+ my $key_sector = DBM::Deep::Engine::Sector::Scalar->new({
+ engine => $engine,
+ data => $args->{key},
+ });
+
+ $engine->storage->print_at( $spot,
+ $args->{key_md5},
+ pack( $engine->StP($engine->byte_size), $key_sector->offset ),
+ );
+ }
+
+ my $loc = $spot
+ + $engine->hash_size
+ + $engine->byte_size;
+
+ if ( $args->{trans_id} ) {
+ $loc += $engine->byte_size + ($args->{trans_id} - 1) * ( $engine->byte_size + $DBM::Deep::Engine::STALE_SIZE );
+
+ $engine->storage->print_at( $loc,
+ pack( $engine->StP($engine->byte_size), $args->{value}->offset ),
+ pack( $engine->StP($DBM::Deep::Engine::STALE_SIZE), $engine->get_txn_staleness_counter( $args->{trans_id} ) ),
+ );
+ }
+ else {
+ $engine->storage->print_at( $loc,
+ pack( $engine->StP($engine->byte_size), $args->{value}->offset ),
+ );
+ }
+}
+
+sub mark_deleted {
+ my $self = shift;
+ my ($args) = @_;
+ $args ||= {};
+
+ my $engine = $self->engine;
+
+ $args->{trans_id} = $engine->trans_id unless exists $args->{trans_id};
+
+ my $spot = $self->offset + $self->base_size + $self->{idx} * $self->bucket_size;
+ $engine->add_entry( $args->{trans_id}, $spot );
+
+ my $loc = $spot
+ + $engine->hash_size
+ + $engine->byte_size;
+
+ if ( $args->{trans_id} ) {
+ $loc += $engine->byte_size + ($args->{trans_id} - 1) * ( $engine->byte_size + $DBM::Deep::Engine::STALE_SIZE );
+
+ $engine->storage->print_at( $loc,
+ pack( $engine->StP($engine->byte_size), 1 ), # 1 is the marker for deleted
+ pack( $engine->StP($DBM::Deep::Engine::STALE_SIZE), $engine->get_txn_staleness_counter( $args->{trans_id} ) ),
+ );
+ }
+ else {
+ $engine->storage->print_at( $loc,
+ pack( $engine->StP($engine->byte_size), 1 ), # 1 is the marker for deleted
+ );
+ }
+
+}
+
+sub delete_md5 {
+ my $self = shift;
+ my ($args) = @_;
+
+ my $engine = $self->engine;
+ return undef unless $self->{found};
+
+ # Save the location so that we can free the data
+ my $location = $self->get_data_location_for({
+ allow_head => 0,
+ });
+ my $key_sector = $self->get_key_for;
+
+ my $spot = $self->offset + $self->base_size + $self->{idx} * $self->bucket_size;
+ $engine->storage->print_at( $spot,
+ $engine->storage->read_at(
+ $spot + $self->bucket_size,
+ $self->bucket_size * ( $engine->max_buckets - $self->{idx} - 1 ),
+ ),
+ chr(0) x $self->bucket_size,
+ );
+
+ $key_sector->free;
+
+ my $data_sector = $self->engine->_load_sector( $location );
+ my $data = $data_sector->data({ export => 1 });
+ $data_sector->free;
+
+ return $data;
+}
+
+sub get_data_location_for {
+ my $self = shift;
+ my ($args) = @_;
+ $args ||= {};
+
+ $args->{allow_head} = 0 unless exists $args->{allow_head};
+ $args->{trans_id} = $self->engine->trans_id unless exists $args->{trans_id};
+ $args->{idx} = $self->{idx} unless exists $args->{idx};
+
+ my $e = $self->engine;
+
+ my $spot = $self->offset + $self->base_size
+ + $args->{idx} * $self->bucket_size
+ + $e->hash_size
+ + $e->byte_size;
+
+ if ( $args->{trans_id} ) {
+ $spot += $e->byte_size + ($args->{trans_id} - 1) * ( $e->byte_size + $DBM::Deep::Engine::STALE_SIZE );
+ }
+
+ my $buffer = $e->storage->read_at(
+ $spot,
+ $e->byte_size + $DBM::Deep::Engine::STALE_SIZE,
+ );
+ my ($loc, $staleness) = unpack( $e->StP($e->byte_size) . ' ' . $e->StP($DBM::Deep::Engine::STALE_SIZE), $buffer );
+
+ # XXX Merge the two if-clauses below
+ if ( $args->{trans_id} ) {
+ # We have found an entry that is old, so get rid of it
+ if ( $staleness != (my $s = $e->get_txn_staleness_counter( $args->{trans_id} ) ) ) {
+ $e->storage->print_at(
+ $spot,
+ pack( $e->StP($e->byte_size) . ' ' . $e->StP($DBM::Deep::Engine::STALE_SIZE), (0) x 2 ),
+ );
+ $loc = 0;
+ }
+ }
+
+ # If we're in a transaction and we never wrote to this location, try the
+ # HEAD instead.
+ if ( $args->{trans_id} && !$loc && $args->{allow_head} ) {
+ return $self->get_data_location_for({
+ trans_id => 0,
+ allow_head => 1,
+ idx => $args->{idx},
+ });
+ }
+
+ return $loc <= 1 ? 0 : $loc;
+}
+
+sub get_data_for {
+ my $self = shift;
+ my ($args) = @_;
+ $args ||= {};
+
+ return unless $self->{found};
+ my $location = $self->get_data_location_for({
+ allow_head => $args->{allow_head},
+ });
+ return $self->engine->_load_sector( $location );
+}
+
+sub get_key_for {
+ my $self = shift;
+ my ($idx) = @_;
+ $idx = $self->{idx} unless defined $idx;
+
+ if ( $idx >= $self->engine->max_buckets ) {
+ DBM::Deep->_throw_error( "get_key_for(): Attempting to retrieve $idx" );
+ }
+
+ my $location = $self->engine->storage->read_at(
+ $self->offset + $self->base_size + $idx * $self->bucket_size + $self->engine->hash_size,
+ $self->engine->byte_size,
+ );
+ $location = unpack( $self->engine->StP($self->engine->byte_size), $location );
+ DBM::Deep->_throw_error( "get_key_for: No location?" ) unless $location;
+
+ return $self->engine->_load_sector( $location );
+}
+
+1;
+__END__
--- /dev/null
+package DBM::Deep::Engine::Sector::Data;
+
+use 5.006;
+
+use strict;
+use warnings FATAL => 'all';
+
+our $VERSION = '0.01';
+
+use DBM::Deep::Engine::Sector;
+our @ISA = qw( DBM::Deep::Engine::Sector );
+
+# This is in bytes
+sub size { $_[0]{engine}->data_sector_size }
+sub free_meth { return '_add_free_data_sector' }
+
+sub clone {
+ my $self = shift;
+ return ref($self)->new({
+ engine => $self->engine,
+ type => $self->type,
+ data => $self->data,
+ });
+}
+
+1;
+__END__
--- /dev/null
+#TODO: Convert this to a string
+package DBM::Deep::Engine::Sector::Index;
+
+use 5.006;
+
+use strict;
+use warnings FATAL => 'all';
+
+use DBM::Deep::Engine::Sector;
+our @ISA = qw( DBM::Deep::Engine::Sector );
+
+sub _init {
+ my $self = shift;
+
+ my $engine = $self->engine;
+
+ unless ( $self->offset ) {
+ my $leftover = $self->size - $self->base_size;
+
+ $self->{offset} = $engine->_request_index_sector( $self->size );
+ $engine->storage->print_at( $self->offset, $engine->SIG_INDEX ); # Sector type
+ # Skip staleness counter
+ $engine->storage->print_at( $self->offset + $self->base_size,
+ chr(0) x $leftover, # Zero-fill the rest
+ );
+ }
+
+ return $self;
+}
+
+#XXX Change here
+sub size {
+ my $self = shift;
+ unless ( $self->{size} ) {
+ my $e = $self->engine;
+ $self->{size} = $self->base_size + $e->byte_size * $e->hash_chars;
+ }
+ return $self->{size};
+}
+
+sub free_meth { return '_add_free_index_sector' }
+
+sub free {
+ my $self = shift;
+ my $e = $self->engine;
+
+ for my $i ( 0 .. $e->hash_chars - 1 ) {
+ my $l = $self->get_entry( $i ) or next;
+ $e->_load_sector( $l )->free;
+ }
+
+ $self->SUPER::free();
+}
+
+sub _loc_for {
+ my $self = shift;
+ my ($idx) = @_;
+ return $self->offset + $self->base_size + $idx * $self->engine->byte_size;
+}
+
+sub get_entry {
+ my $self = shift;
+ my ($idx) = @_;
+
+ my $e = $self->engine;
+
+ DBM::Deep->_throw_error( "get_entry: Out of range ($idx)" )
+ if $idx < 0 || $idx >= $e->hash_chars;
+
+ return unpack(
+ $e->StP($e->byte_size),
+ $e->storage->read_at( $self->_loc_for( $idx ), $e->byte_size ),
+ );
+}
+
+sub set_entry {
+ my $self = shift;
+ my ($idx, $loc) = @_;
+
+ my $e = $self->engine;
+
+ DBM::Deep->_throw_error( "set_entry: Out of range ($idx)" )
+ if $idx < 0 || $idx >= $e->hash_chars;
+
+ $self->engine->storage->print_at(
+ $self->_loc_for( $idx ),
+ pack( $e->StP($e->byte_size), $loc ),
+ );
+}
+
+1;
+__END__
--- /dev/null
+package DBM::Deep::Engine::Sector::Null;
+
+use 5.006;
+
+use strict;
+use warnings FATAL => 'all';
+
+use DBM::Deep::Engine::Sector::Data;
+our @ISA = qw( DBM::Deep::Engine::Sector::Data );
+
+sub type { $_[0]{engine}->SIG_NULL }
+sub data_length { 0 }
+sub data { return }
+
+sub _init {
+ my $self = shift;
+
+ my $engine = $self->engine;
+
+ unless ( $self->offset ) {
+ $self->{offset} = $engine->_request_data_sector( $self->size );
+
+ my $string = chr(0) x $self->size;
+
+ substr( $string, 0, 1, $self->type );
+ substr( $string, $self->base_size, $engine->byte_size + 1,
+ pack( $engine->StP($engine->byte_size), 0 ) # Chain loc
+ . pack( $engine->StP(1), $self->data_length ), # Data length
+ );
+
+ $engine->storage->print_at( $self->offset, $string );
+
+ return;
+ }
+}
+
+1;
+__END__
--- /dev/null
+#TODO: Convert this to a string
+package DBM::Deep::Engine::Sector::Reference;
+
+use 5.006;
+
+use strict;
+use warnings FATAL => 'all';
+
+use Scalar::Util ();
+
+use DBM::Deep::Null;
+
+use DBM::Deep::Engine::Sector::Data;
+our @ISA = qw( DBM::Deep::Engine::Sector::Data );
+
+sub _init {
+ my $self = shift;
+
+ my $e = $self->engine;
+
+ unless ( $self->offset ) {
+ my $classname = Scalar::Util::blessed( delete $self->{data} );
+ my $leftover = $self->size - $self->base_size - 3 * $e->byte_size;
+
+ my $class_offset = 0;
+ if ( defined $classname ) {
+ my $class_sector = DBM::Deep::Engine::Sector::Scalar->new({
+ engine => $e,
+ data => $classname,
+ });
+ $class_offset = $class_sector->offset;
+ }
+
+ $self->{offset} = $e->_request_data_sector( $self->size );
+ $e->storage->print_at( $self->offset, $self->type ); # Sector type
+ # Skip staleness counter
+ $e->storage->print_at( $self->offset + $self->base_size,
+ pack( $e->StP($e->byte_size), 0 ), # Index/BList loc
+ pack( $e->StP($e->byte_size), $class_offset ), # Classname loc
+ pack( $e->StP($e->byte_size), 1 ), # Initial refcount
+ chr(0) x $leftover, # Zero-fill the rest
+ );
+ }
+ else {
+ $self->{type} = $e->storage->read_at( $self->offset, 1 );
+ }
+
+ $self->{staleness} = unpack(
+ $e->StP($DBM::Deep::Engine::STALE_SIZE),
+ $e->storage->read_at( $self->offset + $e->SIG_SIZE, $DBM::Deep::Engine::STALE_SIZE ),
+ );
+
+ return;
+}
+
+sub staleness { $_[0]{staleness} }
+
+sub get_data_location_for {
+ my $self = shift;
+ my ($args) = @_;
+
+ # Assume that the head is not allowed unless otherwise specified.
+ $args->{allow_head} = 0 unless exists $args->{allow_head};
+
+ # Assume we don't create a new blist location unless otherwise specified.
+ $args->{create} = 0 unless exists $args->{create};
+
+ my $blist = $self->get_bucket_list({
+ key_md5 => $args->{key_md5},
+ key => $args->{key},
+ create => $args->{create},
+ });
+ return unless $blist && $blist->{found};
+
+ # At this point, $blist knows where the md5 is. What it -doesn't- know yet
+ # is whether or not this transaction has this key. That's part of the next
+ # function call.
+ my $location = $blist->get_data_location_for({
+ allow_head => $args->{allow_head},
+ }) or return;
+
+ return $location;
+}
+
+sub get_data_for {
+ my $self = shift;
+ my ($args) = @_;
+
+ my $location = $self->get_data_location_for( $args )
+ or return;
+
+ return $self->engine->_load_sector( $location );
+}
+
+sub write_data {
+ my $self = shift;
+ my ($args) = @_;
+
+ my $blist = $self->get_bucket_list({
+ key_md5 => $args->{key_md5},
+ key => $args->{key},
+ create => 1,
+ }) or DBM::Deep->_throw_error( "How did write_data fail (no blist)?!" );
+
+ # Handle any transactional bookkeeping.
+ if ( $self->engine->trans_id ) {
+ if ( ! $blist->has_md5 ) {
+ $blist->mark_deleted({
+ trans_id => 0,
+ });
+ }
+ }
+ else {
+ my @trans_ids = $self->engine->get_running_txn_ids;
+ if ( $blist->has_md5 ) {
+ if ( @trans_ids ) {
+ my $old_value = $blist->get_data_for;
+ foreach my $other_trans_id ( @trans_ids ) {
+ next if $blist->get_data_location_for({
+ trans_id => $other_trans_id,
+ allow_head => 0,
+ });
+ $blist->write_md5({
+ trans_id => $other_trans_id,
+ key => $args->{key},
+ key_md5 => $args->{key_md5},
+ value => $old_value->clone,
+ });
+ }
+ }
+ }
+ else {
+ if ( @trans_ids ) {
+ foreach my $other_trans_id ( @trans_ids ) {
+ #XXX This doesn't seem to possible to ever happen . . .
+ next if $blist->get_data_location_for({ trans_id => $other_trans_id, allow_head => 0 });
+ $blist->mark_deleted({
+ trans_id => $other_trans_id,
+ });
+ }
+ }
+ }
+ }
+
+ #XXX Is this safe to do transactionally?
+ # Free the place we're about to write to.
+ if ( $blist->get_data_location_for({ allow_head => 0 }) ) {
+ $blist->get_data_for({ allow_head => 0 })->free;
+ }
+
+ $blist->write_md5({
+ key => $args->{key},
+ key_md5 => $args->{key_md5},
+ value => $args->{value},
+ });
+}
+
+sub delete_key {
+ my $self = shift;
+ my ($args) = @_;
+
+ # XXX What should happen if this fails?
+ my $blist = $self->get_bucket_list({
+ key_md5 => $args->{key_md5},
+ }) or DBM::Deep->_throw_error( "How did delete_key fail (no blist)?!" );
+
+ # Save the location so that we can free the data
+ my $location = $blist->get_data_location_for({
+ allow_head => 0,
+ });
+ my $old_value = $location && $self->engine->_load_sector( $location );
+
+ my @trans_ids = $self->engine->get_running_txn_ids;
+
+ # If we're the HEAD and there are running txns, then we need to clone this value to the other
+ # transactions to preserve Isolation.
+ if ( $self->engine->trans_id == 0 ) {
+ if ( @trans_ids ) {
+ foreach my $other_trans_id ( @trans_ids ) {
+ next if $blist->get_data_location_for({ trans_id => $other_trans_id, allow_head => 0 });
+ $blist->write_md5({
+ trans_id => $other_trans_id,
+ key => $args->{key},
+ key_md5 => $args->{key_md5},
+ value => $old_value->clone,
+ });
+ }
+ }
+ }
+
+ my $data;
+ if ( @trans_ids ) {
+ $blist->mark_deleted( $args );
+
+ if ( $old_value ) {
+ $data = $old_value->data({ export => 1 });
+ $old_value->free;
+ }
+ }
+ else {
+ $data = $blist->delete_md5( $args );
+ }
+
+ return $data;
+}
+
+sub get_blist_loc {
+ my $self = shift;
+
+ my $e = $self->engine;
+ my $blist_loc = $e->storage->read_at( $self->offset + $self->base_size, $e->byte_size );
+ return unpack( $e->StP($e->byte_size), $blist_loc );
+}
+
+sub get_bucket_list {
+ my $self = shift;
+ my ($args) = @_;
+ $args ||= {};
+
+ # XXX Add in check here for recycling?
+
+ my $engine = $self->engine;
+
+ my $blist_loc = $self->get_blist_loc;
+
+ # There's no index or blist yet
+ unless ( $blist_loc ) {
+ return unless $args->{create};
+
+ my $blist = DBM::Deep::Engine::Sector::BucketList->new({
+ engine => $engine,
+ key_md5 => $args->{key_md5},
+ });
+
+ $engine->storage->print_at( $self->offset + $self->base_size,
+ pack( $engine->StP($engine->byte_size), $blist->offset ),
+ );
+
+ return $blist;
+ }
+
+ my $sector = $engine->_load_sector( $blist_loc )
+ or DBM::Deep->_throw_error( "Cannot read sector at $blist_loc in get_bucket_list()" );
+ my $i = 0;
+ my $last_sector = undef;
+ while ( $sector->isa( 'DBM::Deep::Engine::Sector::Index' ) ) {
+ $blist_loc = $sector->get_entry( ord( substr( $args->{key_md5}, $i++, 1 ) ) );
+ $last_sector = $sector;
+ if ( $blist_loc ) {
+ $sector = $engine->_load_sector( $blist_loc )
+ or DBM::Deep->_throw_error( "Cannot read sector at $blist_loc in get_bucket_list()" );
+ }
+ else {
+ $sector = undef;
+ last;
+ }
+ }
+
+ # This means we went through the Index sector(s) and found an empty slot
+ unless ( $sector ) {
+ return unless $args->{create};
+
+ DBM::Deep->_throw_error( "No last_sector when attempting to build a new entry" )
+ unless $last_sector;
+
+ my $blist = DBM::Deep::Engine::Sector::BucketList->new({
+ engine => $engine,
+ key_md5 => $args->{key_md5},
+ });
+
+ $last_sector->set_entry( ord( substr( $args->{key_md5}, $i - 1, 1 ) ) => $blist->offset );
+
+ return $blist;
+ }
+
+ $sector->find_md5( $args->{key_md5} );
+
+ # See whether or not we need to reindex the bucketlist
+ # Yes, the double-braces are there for a reason. if() doesn't create a redo-able block,
+ # so we have to create a bare block within the if() for redo-purposes. Patch and idea
+ # submitted by sprout@cpan.org. -RobK, 2008-01-09
+ if ( !$sector->has_md5 && $args->{create} && $sector->{idx} == -1 ) {{
+ my $redo;
+
+ my $new_index = DBM::Deep::Engine::Sector::Index->new({
+ engine => $engine,
+ });
+
+ my %blist_cache;
+ #XXX q.v. the comments for this function.
+ foreach my $entry ( $sector->chopped_up ) {
+ my ($spot, $md5) = @{$entry};
+ my $idx = ord( substr( $md5, $i, 1 ) );
+
+ # XXX This is inefficient
+ my $blist = $blist_cache{$idx}
+ ||= DBM::Deep::Engine::Sector::BucketList->new({
+ engine => $engine,
+ });
+
+ $new_index->set_entry( $idx => $blist->offset );
+
+ my $new_spot = $blist->write_at_next_open( $md5 );
+ $engine->reindex_entry( $spot => $new_spot );
+ }
+
+ # Handle the new item separately.
+ {
+ my $idx = ord( substr( $args->{key_md5}, $i, 1 ) );
+
+ # If all the previous blist's items have been thrown into one
+ # blist and the new item belongs in there too, we need
+ # another index.
+ if ( keys %blist_cache == 1 and each %blist_cache == $idx ) {
+ ++$i, ++$redo;
+ } else {
+ my $blist = $blist_cache{$idx}
+ ||= DBM::Deep::Engine::Sector::BucketList->new({
+ engine => $engine,
+ });
+
+ $new_index->set_entry( $idx => $blist->offset );
+
+ #XXX THIS IS HACKY!
+ $blist->find_md5( $args->{key_md5} );
+ $blist->write_md5({
+ key => $args->{key},
+ key_md5 => $args->{key_md5},
+ value => DBM::Deep::Engine::Sector::Null->new({
+ engine => $engine,
+ data => undef,
+ }),
+ });
+ }
+# my $blist = $blist_cache{$idx}
+# ||= DBM::Deep::Engine::Sector::BucketList->new({
+# engine => $engine,
+# });
+#
+# $new_index->set_entry( $idx => $blist->offset );
+#
+# #XXX THIS IS HACKY!
+# $blist->find_md5( $args->{key_md5} );
+# $blist->write_md5({
+# key => $args->{key},
+# key_md5 => $args->{key_md5},
+# value => DBM::Deep::Engine::Sector::Null->new({
+# engine => $engine,
+# data => undef,
+# }),
+# });
+ }
+
+ if ( $last_sector ) {
+ $last_sector->set_entry(
+ ord( substr( $args->{key_md5}, $i - 1, 1 ) ),
+ $new_index->offset,
+ );
+ } else {
+ $engine->storage->print_at( $self->offset + $self->base_size,
+ pack( $engine->StP($engine->byte_size), $new_index->offset ),
+ );
+ }
+
+ $sector->clear;
+ $sector->free;
+
+ if ( $redo ) {
+ (undef, $sector) = %blist_cache;
+ $last_sector = $new_index;
+ redo;
+ }
+
+ $sector = $blist_cache{ ord( substr( $args->{key_md5}, $i, 1 ) ) };
+ $sector->find_md5( $args->{key_md5} );
+ }}
+
+ return $sector;
+}
+
+sub get_class_offset {
+ my $self = shift;
+
+ my $e = $self->engine;
+ return unpack(
+ $e->StP($e->byte_size),
+ $e->storage->read_at(
+ $self->offset + $self->base_size + 1 * $e->byte_size, $e->byte_size,
+ ),
+ );
+}
+
+sub get_classname {
+ my $self = shift;
+
+ my $class_offset = $self->get_class_offset;
+
+ return unless $class_offset;
+
+ return $self->engine->_load_sector( $class_offset )->data;
+}
+
+sub data {
+ my $self = shift;
+ my ($args) = @_;
+ $args ||= {};
+
+ my $obj;
+ unless ( $obj = $self->engine->cache->{ $self->offset } ) {
+ $obj = DBM::Deep->new({
+ type => $self->type,
+ base_offset => $self->offset,
+ staleness => $self->staleness,
+ storage => $self->engine->storage,
+ engine => $self->engine,
+ });
+
+ if ( $self->engine->storage->{autobless} ) {
+ my $classname = $self->get_classname;
+ if ( defined $classname ) {
+ bless $obj, $classname;
+ }
+ }
+
+ $self->engine->cache->{$self->offset} = $obj;
+ }
+
+ # We're not exporting, so just return.
+ unless ( $args->{export} ) {
+ return $obj;
+ }
+
+ # We shouldn't export if this is still referred to.
+ if ( $self->get_refcount > 1 ) {
+ return $obj;
+ }
+
+ return $obj->export;
+}
+
+sub free {
+ my $self = shift;
+
+ # We're not ready to be removed yet.
+ if ( $self->decrement_refcount > 0 ) {
+ return;
+ }
+
+ # Rebless the object into DBM::Deep::Null.
+ eval { %{ $self->engine->cache->{ $self->offset } } = (); };
+ eval { @{ $self->engine->cache->{ $self->offset } } = (); };
+ bless $self->engine->cache->{ $self->offset }, 'DBM::Deep::Null';
+ delete $self->engine->cache->{ $self->offset };
+
+ my $blist_loc = $self->get_blist_loc;
+ $self->engine->_load_sector( $blist_loc )->free if $blist_loc;
+
+ my $class_loc = $self->get_class_offset;
+ $self->engine->_load_sector( $class_loc )->free if $class_loc;
+
+ $self->SUPER::free();
+}
+
+sub increment_refcount {
+ my $self = shift;
+
+ my $refcount = $self->get_refcount;
+
+ $refcount++;
+
+ $self->write_refcount( $refcount );
+
+ return $refcount;
+}
+
+sub decrement_refcount {
+ my $self = shift;
+
+ my $refcount = $self->get_refcount;
+
+ $refcount--;
+
+ $self->write_refcount( $refcount );
+
+ return $refcount;
+}
+
+sub get_refcount {
+ my $self = shift;
+
+ my $e = $self->engine;
+ return unpack(
+ $e->StP($e->byte_size),
+ $e->storage->read_at(
+ $self->offset + $self->base_size + 2 * $e->byte_size, $e->byte_size,
+ ),
+ );
+}
+
+sub write_refcount {
+ my $self = shift;
+ my ($num) = @_;
+
+ my $e = $self->engine;
+ $e->storage->print_at(
+ $self->offset + $self->base_size + 2 * $e->byte_size,
+ pack( $e->StP($e->byte_size), $num ),
+ );
+}
+
+
+1;
+__END__
+
--- /dev/null
+#TODO: Convert this to a string
+package DBM::Deep::Engine::Sector::Scalar;
+
+use 5.006;
+
+use strict;
+use warnings FATAL => 'all';
+
+our $VERSION = '0.01';
+
+use DBM::Deep::Engine::Sector::Data;
+our @ISA = qw( DBM::Deep::Engine::Sector::Data );
+
+sub free {
+ my $self = shift;
+
+ my $chain_loc = $self->chain_loc;
+
+ $self->SUPER::free();
+
+ if ( $chain_loc ) {
+ $self->engine->_load_sector( $chain_loc )->free;
+ }
+
+ return;
+}
+
+sub type { $_[0]{engine}->SIG_DATA }
+sub _init {
+ my $self = shift;
+
+ my $engine = $self->engine;
+
+ unless ( $self->offset ) {
+ my $data_section = $self->size - $self->base_size - $engine->byte_size - 1;
+
+ $self->{offset} = $engine->_request_data_sector( $self->size );
+
+ my $data = delete $self->{data};
+ my $dlen = length $data;
+ my $continue = 1;
+ my $curr_offset = $self->offset;
+ while ( $continue ) {
+
+ my $next_offset = 0;
+
+ my ($leftover, $this_len, $chunk);
+ if ( $dlen > $data_section ) {
+ $leftover = 0;
+ $this_len = $data_section;
+ $chunk = substr( $data, 0, $this_len );
+
+ $dlen -= $data_section;
+ $next_offset = $engine->_request_data_sector( $self->size );
+ $data = substr( $data, $this_len );
+ }
+ else {
+ $leftover = $data_section - $dlen;
+ $this_len = $dlen;
+ $chunk = $data;
+
+ $continue = 0;
+ }
+
+ $engine->storage->print_at( $curr_offset, $self->type ); # Sector type
+ # Skip staleness
+ $engine->storage->print_at( $curr_offset + $self->base_size,
+ pack( $engine->StP($engine->byte_size), $next_offset ), # Chain loc
+ pack( $engine->StP(1), $this_len ), # Data length
+ $chunk, # Data to be stored in this sector
+ chr(0) x $leftover, # Zero-fill the rest
+ );
+
+ $curr_offset = $next_offset;
+ }
+
+ return;
+ }
+}
+
+sub data_length {
+ my $self = shift;
+
+ my $buffer = $self->engine->storage->read_at(
+ $self->offset + $self->base_size + $self->engine->byte_size, 1
+ );
+
+ return unpack( $self->engine->StP(1), $buffer );
+}
+
+sub chain_loc {
+ my $self = shift;
+ return unpack(
+ $self->engine->StP($self->engine->byte_size),
+ $self->engine->storage->read_at(
+ $self->offset + $self->base_size,
+ $self->engine->byte_size,
+ ),
+ );
+}
+
+sub data {
+ my $self = shift;
+# my ($args) = @_;
+# $args ||= {};
+
+ my $data;
+ while ( 1 ) {
+ my $chain_loc = $self->chain_loc;
+
+ $data .= $self->engine->storage->read_at(
+ $self->offset + $self->base_size + $self->engine->byte_size + 1, $self->data_length,
+ );
+
+ last unless $chain_loc;
+
+ $self = $self->engine->_load_sector( $chain_loc );
+ }
+
+ return $data;
+}
+
+1;
+__END__
use 5.006_000;
use strict;
-use warnings;
-
-our $VERSION = q(1.0013);
+use warnings FATAL => 'all';
use Fcntl qw( :DEFAULT :flock :seek );
use 5.006_000;
use strict;
-use warnings;
-
-our $VERSION = q(1.0013);
+use warnings FATAL => 'all';
use base 'DBM::Deep';
--- /dev/null
+package DBM::Deep::Iterator;
+
+use 5.006;
+
+use strict;
+use warnings FATAL => 'all';
+
+use Scalar::Util ();
+
+use DBM::Deep::Iterator::Index;
+use DBM::Deep::Iterator::BucketList;
+
+sub new {
+ my $class = shift;
+ my ($args) = @_;
+
+ my $self = bless {
+ breadcrumbs => [],
+ engine => $args->{engine},
+ base_offset => $args->{base_offset},
+ }, $class;
+
+ Scalar::Util::weaken( $self->{engine} );
+
+ return $self;
+}
+
+sub reset { $_[0]{breadcrumbs} = [] }
+
+sub get_sector_iterator {
+ my $self = shift;
+ my ($loc) = @_;
+
+ my $sector = $self->{engine}->_load_sector( $loc )
+ or return;
+
+ if ( $sector->isa( 'DBM::Deep::Engine::Sector::Index' ) ) {
+ return DBM::Deep::Iterator::Index->new({
+ iterator => $self,
+ sector => $sector,
+ });
+ }
+ elsif ( $sector->isa( 'DBM::Deep::Engine::Sector::BucketList' ) ) {
+ return DBM::Deep::Iterator::BucketList->new({
+ iterator => $self,
+ sector => $sector,
+ });
+ }
+
+ DBM::Deep->_throw_error( "get_sector_iterator(): Why did $loc make a $sector?" );
+}
+
+sub get_next_key {
+ my $self = shift;
+ my ($obj) = @_;
+
+ my $crumbs = $self->{breadcrumbs};
+ my $e = $self->{engine};
+
+ unless ( @$crumbs ) {
+ # This will be a Reference sector
+ my $sector = $e->_load_sector( $self->{base_offset} )
+ # If no sector is found, thist must have been deleted from under us.
+ or return;
+
+ if ( $sector->staleness != $obj->_staleness ) {
+ return;
+ }
+
+ my $loc = $sector->get_blist_loc
+ or return;
+
+ push @$crumbs, $self->get_sector_iterator( $loc );
+ }
+
+ FIND_NEXT_KEY: {
+ # We're at the end.
+ unless ( @$crumbs ) {
+ $self->reset;
+ return;
+ }
+
+ my $iterator = $crumbs->[-1];
+
+ # This level is done.
+ if ( $iterator->at_end ) {
+ pop @$crumbs;
+ redo FIND_NEXT_KEY;
+ }
+
+ if ( $iterator->isa( 'DBM::Deep::Iterator::Index' ) ) {
+ # If we don't have any more, it will be caught at the
+ # prior check.
+ if ( my $next = $iterator->get_next_iterator ) {
+ push @$crumbs, $next;
+ }
+ redo FIND_NEXT_KEY;
+ }
+
+ unless ( $iterator->isa( 'DBM::Deep::Iterator::BucketList' ) ) {
+ DBM::Deep->_throw_error(
+ "Should have a bucketlist iterator here - instead have $iterator"
+ );
+ }
+
+ # At this point, we have a BucketList iterator
+ my $key = $iterator->get_next_key;
+ if ( defined $key ) {
+ return $key;
+ }
+ #XXX else { $iterator->set_to_end() } ?
+
+ # We hit the end of the bucketlist iterator, so redo
+ redo FIND_NEXT_KEY;
+ }
+
+ DBM::Deep->_throw_error( "get_next_key(): How did we get here?" );
+}
+
+1;
+__END__
--- /dev/null
+package DBM::Deep::Iterator::BucketList;
+
+use 5.006;
+
+use strict;
+use warnings FATAL => 'all';
+
+sub new {
+ my $self = bless $_[1] => $_[0];
+ $self->{curr_index} = 0;
+ return $self;
+}
+
+sub at_end {
+ my $self = shift;
+ return $self->{curr_index} >= $self->{iterator}{engine}->max_buckets;
+}
+
+sub get_next_key {
+ my $self = shift;
+
+ return if $self->at_end;
+
+ my $idx = $self->{curr_index}++;
+
+ my $data_loc = $self->{sector}->get_data_location_for({
+ allow_head => 1,
+ idx => $idx,
+ }) or return;
+
+ #XXX Do we want to add corruption checks here?
+ return $self->{sector}->get_key_for( $idx )->data;
+}
+
+1;
+__END__
--- /dev/null
+package DBM::Deep::Iterator::Index;
+
+use 5.006;
+
+use strict;
+use warnings FATAL => 'all';
+
+sub new {
+ my $self = bless $_[1] => $_[0];
+ $self->{curr_index} = 0;
+ return $self;
+}
+
+sub at_end {
+ my $self = shift;
+ return $self->{curr_index} >= $self->{iterator}{engine}->hash_chars;
+}
+
+sub get_next_iterator {
+ my $self = shift;
+
+ my $loc;
+ while ( !$loc ) {
+ return if $self->at_end;
+ $loc = $self->{sector}->get_entry( $self->{curr_index}++ );
+ }
+
+ return $self->{iterator}->get_sector_iterator( $loc );
+}
+
+1;
+__END__
--- /dev/null
+# This was copied from MARCEL's Class::Null. However, I couldn't use it because
+# I need an undef value, not an implementation of the Null Class pattern.
+package DBM::Deep::Null;
+
+use 5.006;
+
+use strict;
+use warnings FATAL => 'all';
+
+use overload
+ 'bool' => sub { undef },
+ '""' => sub { undef },
+ '0+' => sub { undef },
+ fallback => 1,
+ nomethod => 'AUTOLOAD';
+
+sub AUTOLOAD { return; }
+
+1;
+__END__
projects / dbsrgits/DBM-Deep.git / commitdiff