--- /dev/null
+package DBM::Deep::10002;
+
+use 5.006_000;
+
+use strict;
+use warnings;
+
+our $VERSION = q(1.0002);
+
+use Fcntl qw( :flock );
+
+use Clone ();
+use Digest::MD5 ();
+use FileHandle::Fmode ();
+use Scalar::Util ();
+
+#use DBM::Deep::10002::Engine;
+#use DBM::Deep::10002::File;
+
+##
+# Setup constants for users to pass to new()
+##
+sub TYPE_HASH () { DBM::Deep::10002::Engine->SIG_HASH }
+sub TYPE_ARRAY () { DBM::Deep::10002::Engine->SIG_ARRAY }
+
+# This is used in all the children of this class in their TIE<type> methods.
+sub _get_args {
+ my $proto = shift;
+
+ my $args;
+ if (scalar(@_) > 1) {
+ if ( @_ % 2 ) {
+ $proto->_throw_error( "Odd number of parameters to " . (caller(1))[2] );
+ }
+ $args = {@_};
+ }
+ elsif ( ref $_[0] ) {
+ unless ( eval { local $SIG{'__DIE__'}; %{$_[0]} || 1 } ) {
+ $proto->_throw_error( "Not a hashref in args to " . (caller(1))[2] );
+ }
+ $args = $_[0];
+ }
+ else {
+ $args = { file => shift };
+ }
+
+ return $args;
+}
+
+sub new {
+ ##
+ # Class constructor method for Perl OO interface.
+ # Calls tie() and returns blessed reference to tied hash or array,
+ # providing a hybrid OO/tie interface.
+ ##
+ my $class = shift;
+ my $args = $class->_get_args( @_ );
+
+ ##
+ # Check if we want a tied hash or array.
+ ##
+ my $self;
+ if (defined($args->{type}) && $args->{type} eq TYPE_ARRAY) {
+ $class = 'DBM::Deep::10002::Array';
+ #require DBM::Deep::10002::Array;
+ tie @$self, $class, %$args;
+ }
+ else {
+ $class = 'DBM::Deep::10002::Hash';
+ #require DBM::Deep::10002::Hash;
+ tie %$self, $class, %$args;
+ }
+
+ return bless $self, $class;
+}
+
+# This initializer is called from the various TIE* methods. new() calls tie(),
+# which allows for a single point of entry.
+sub _init {
+ my $class = shift;
+ my ($args) = @_;
+
+ $args->{storage} = DBM::Deep::10002::File->new( $args )
+ unless exists $args->{storage};
+
+ # locking implicitly enables autoflush
+ if ($args->{locking}) { $args->{autoflush} = 1; }
+
+ # These are the defaults to be optionally overridden below
+ my $self = bless {
+ type => TYPE_HASH,
+ base_offset => undef,
+ staleness => undef,
+
+ storage => undef,
+ engine => undef,
+ }, $class;
+
+ $args->{engine} = DBM::Deep::10002::Engine->new( { %{$args}, obj => $self } )
+ unless exists $args->{engine};
+
+ # Grab the parameters we want to use
+ foreach my $param ( keys %$self ) {
+ next unless exists $args->{$param};
+ $self->{$param} = $args->{$param};
+ }
+
+ eval {
+ local $SIG{'__DIE__'};
+
+ $self->lock;
+ $self->_engine->setup_fh( $self );
+ $self->_storage->set_inode;
+ $self->unlock;
+ }; if ( $@ ) {
+ my $e = $@;
+ eval { local $SIG{'__DIE__'}; $self->unlock; };
+ die $e;
+ }
+
+ return $self;
+}
+
+sub TIEHASH {
+ shift;
+ #require DBM::Deep::10002::Hash;
+ return DBM::Deep::10002::Hash->TIEHASH( @_ );
+}
+
+sub TIEARRAY {
+ shift;
+ #require DBM::Deep::10002::Array;
+ return DBM::Deep::10002::Array->TIEARRAY( @_ );
+}
+
+sub lock {
+ my $self = shift->_get_self;
+ return $self->_storage->lock( $self, @_ );
+}
+
+sub unlock {
+ my $self = shift->_get_self;
+ return $self->_storage->unlock( $self, @_ );
+}
+
+sub _copy_value {
+ my $self = shift->_get_self;
+ my ($spot, $value) = @_;
+
+ if ( !ref $value ) {
+ ${$spot} = $value;
+ }
+ elsif ( eval { local $SIG{__DIE__}; $value->isa( 'DBM::Deep::10002' ) } ) {
+ ${$spot} = $value->_repr;
+ $value->_copy_node( ${$spot} );
+ }
+ else {
+ my $r = Scalar::Util::reftype( $value );
+ my $c = Scalar::Util::blessed( $value );
+ if ( $r eq 'ARRAY' ) {
+ ${$spot} = [ @{$value} ];
+ }
+ else {
+ ${$spot} = { %{$value} };
+ }
+ ${$spot} = bless ${$spot}, $c
+ if defined $c;
+ }
+
+ return 1;
+}
+
+#sub _copy_node {
+# die "Must be implemented in a child class\n";
+#}
+#
+#sub _repr {
+# die "Must be implemented in a child class\n";
+#}
+
+sub export {
+ ##
+ # Recursively export into standard Perl hashes and arrays.
+ ##
+ my $self = shift->_get_self;
+
+ my $temp = $self->_repr;
+
+ $self->lock();
+ $self->_copy_node( $temp );
+ $self->unlock();
+
+ my $classname = $self->_engine->get_classname( $self );
+ if ( defined $classname ) {
+ bless $temp, $classname;
+ }
+
+ return $temp;
+}
+
+sub import {
+ ##
+ # Recursively import Perl hash/array structure
+ ##
+ if (!ref($_[0])) { return; } # Perl calls import() on use -- ignore
+
+ my $self = shift->_get_self;
+ my ($struct) = @_;
+
+ # struct is not a reference, so just import based on our type
+ if (!ref($struct)) {
+ $struct = $self->_repr( @_ );
+ }
+
+ #XXX This isn't the best solution. Better would be to use Data::Walker,
+ #XXX but that's a lot more thinking than I want to do right now.
+ eval {
+ local $SIG{'__DIE__'};
+ $self->_import( Clone::clone( $struct ) );
+ }; if ( my $e = $@ ) {
+ die $e;
+ }
+
+ return 1;
+}
+
+#XXX Need to keep track of who has a fh to this file in order to
+#XXX close them all prior to optimize on Win32/cygwin
+sub optimize {
+ ##
+ # Rebuild entire database into new file, then move
+ # it back on top of original.
+ ##
+ my $self = shift->_get_self;
+
+#XXX Need to create a new test for this
+# if ($self->_storage->{links} > 1) {
+# $self->_throw_error("Cannot optimize: reference count is greater than 1");
+# }
+
+ #XXX Do we have to lock the tempfile?
+
+ my $db_temp = DBM::Deep::10002->new(
+ file => $self->_storage->{file} . '.tmp',
+ type => $self->_type,
+
+ # Bring over all the parameters that we need to bring over
+ num_txns => $self->_engine->num_txns,
+ byte_size => $self->_engine->byte_size,
+ max_buckets => $self->_engine->max_buckets,
+ );
+
+ $self->lock();
+ $self->_copy_node( $db_temp );
+ undef $db_temp;
+
+ ##
+ # Attempt to copy user, group and permissions over to new file
+ ##
+ my @stats = stat($self->_fh);
+ my $perms = $stats[2] & 07777;
+ my $uid = $stats[4];
+ my $gid = $stats[5];
+ chown( $uid, $gid, $self->_storage->{file} . '.tmp' );
+ chmod( $perms, $self->_storage->{file} . '.tmp' );
+
+ # q.v. perlport for more information on this variable
+ if ( $^O eq 'MSWin32' || $^O eq 'cygwin' ) {
+ ##
+ # Potential race condition when optmizing on Win32 with locking.
+ # The Windows filesystem requires that the filehandle be closed
+ # before it is overwritten with rename(). This could be redone
+ # with a soft copy.
+ ##
+ $self->unlock();
+ $self->_storage->close;
+ }
+
+ if (!rename $self->_storage->{file} . '.tmp', $self->_storage->{file}) {
+ unlink $self->_storage->{file} . '.tmp';
+ $self->unlock();
+ $self->_throw_error("Optimize failed: Cannot copy temp file over original: $!");
+ }
+
+ $self->unlock();
+ $self->_storage->close;
+
+ $self->_storage->open;
+ $self->lock();
+ $self->_engine->setup_fh( $self );
+ $self->unlock();
+
+ return 1;
+}
+
+sub clone {
+ ##
+ # Make copy of object and return
+ ##
+ my $self = shift->_get_self;
+
+ return DBM::Deep::10002->new(
+ type => $self->_type,
+ base_offset => $self->_base_offset,
+ staleness => $self->_staleness,
+ storage => $self->_storage,
+ engine => $self->_engine,
+ );
+}
+
+#XXX Migrate this to the engine, where it really belongs and go through some
+# API - stop poking in the innards of someone else..
+{
+ my %is_legal_filter = map {
+ $_ => ~~1,
+ } qw(
+ store_key store_value
+ fetch_key fetch_value
+ );
+
+ sub set_filter {
+ ##
+ # Setup filter function for storing or fetching the key or value
+ ##
+ my $self = shift->_get_self;
+ my $type = lc shift;
+ my $func = shift;
+
+ if ( $is_legal_filter{$type} ) {
+ $self->_storage->{"filter_$type"} = $func;
+ return 1;
+ }
+
+ return;
+ }
+}
+
+sub begin_work {
+ my $self = shift->_get_self;
+ return $self->_engine->begin_work( $self, @_ );
+}
+
+sub rollback {
+ my $self = shift->_get_self;
+ return $self->_engine->rollback( $self, @_ );
+}
+
+sub commit {
+ my $self = shift->_get_self;
+ return $self->_engine->commit( $self, @_ );
+}
+
+##
+# Accessor methods
+##
+
+sub _engine {
+ my $self = $_[0]->_get_self;
+ return $self->{engine};
+}
+
+sub _storage {
+ my $self = $_[0]->_get_self;
+ return $self->{storage};
+}
+
+sub _type {
+ my $self = $_[0]->_get_self;
+ return $self->{type};
+}
+
+sub _base_offset {
+ my $self = $_[0]->_get_self;
+ return $self->{base_offset};
+}
+
+sub _staleness {
+ my $self = $_[0]->_get_self;
+ return $self->{staleness};
+}
+
+sub _fh {
+ my $self = $_[0]->_get_self;
+ return $self->_storage->{fh};
+}
+
+##
+# Utility methods
+##
+
+sub _throw_error {
+ die "DBM::Deep::10002: $_[1]\n";
+ my $n = 0;
+ while( 1 ) {
+ my @caller = caller( ++$n );
+ next if $caller[0] =~ m/^DBM::Deep::10002/;
+
+ die "DBM::Deep::10002: $_[1] at $0 line $caller[2]\n";
+ last;
+ }
+}
+
+sub STORE {
+ ##
+ # Store single hash key/value or array element in database.
+ ##
+ my $self = shift->_get_self;
+ my ($key, $value) = @_;
+
+ if ( !FileHandle::Fmode::is_W( $self->_fh ) ) {
+ $self->_throw_error( 'Cannot write to a readonly filehandle' );
+ }
+
+ ##
+ # Request exclusive lock for writing
+ ##
+ $self->lock( LOCK_EX );
+
+ # User may be storing a complex value, in which case we do not want it run
+ # through the filtering system.
+ if ( !ref($value) && $self->_storage->{filter_store_value} ) {
+ $value = $self->_storage->{filter_store_value}->( $value );
+ }
+
+ $self->_engine->write_value( $self, $key, $value);
+
+ $self->unlock();
+
+ return 1;
+}
+
+sub FETCH {
+ ##
+ # Fetch single value or element given plain key or array index
+ ##
+ my $self = shift->_get_self;
+ my ($key) = @_;
+
+ ##
+ # Request shared lock for reading
+ ##
+ $self->lock( LOCK_SH );
+
+ my $result = $self->_engine->read_value( $self, $key);
+
+ $self->unlock();
+
+ # Filters only apply to scalar values, so the ref check is making
+ # sure the fetched bucket is a scalar, not a child hash or array.
+ return ($result && !ref($result) && $self->_storage->{filter_fetch_value})
+ ? $self->_storage->{filter_fetch_value}->($result)
+ : $result;
+}
+
+sub DELETE {
+ ##
+ # Delete single key/value pair or element given plain key or array index
+ ##
+ my $self = shift->_get_self;
+ my ($key) = @_;
+
+ if ( !FileHandle::Fmode::is_W( $self->_fh ) ) {
+ $self->_throw_error( 'Cannot write to a readonly filehandle' );
+ }
+
+ ##
+ # Request exclusive lock for writing
+ ##
+ $self->lock( LOCK_EX );
+
+ ##
+ # Delete bucket
+ ##
+ my $value = $self->_engine->delete_key( $self, $key);
+
+ if (defined $value && !ref($value) && $self->_storage->{filter_fetch_value}) {
+ $value = $self->_storage->{filter_fetch_value}->($value);
+ }
+
+ $self->unlock();
+
+ return $value;
+}
+
+sub EXISTS {
+ ##
+ # Check if a single key or element exists given plain key or array index
+ ##
+ my $self = shift->_get_self;
+ my ($key) = @_;
+
+ ##
+ # Request shared lock for reading
+ ##
+ $self->lock( LOCK_SH );
+
+ my $result = $self->_engine->key_exists( $self, $key );
+
+ $self->unlock();
+
+ return $result;
+}
+
+sub CLEAR {
+ ##
+ # Clear all keys from hash, or all elements from array.
+ ##
+ my $self = shift->_get_self;
+
+ if ( !FileHandle::Fmode::is_W( $self->_fh ) ) {
+ $self->_throw_error( 'Cannot write to a readonly filehandle' );
+ }
+
+ ##
+ # Request exclusive lock for writing
+ ##
+ $self->lock( LOCK_EX );
+
+ #XXX Rewrite this dreck to do it in the engine as a tight loop vs.
+ # iterating over keys - such a WASTE - is this required for transactional
+ # clearning?! Surely that can be detected in the engine ...
+ if ( $self->_type eq TYPE_HASH ) {
+ my $key = $self->first_key;
+ while ( $key ) {
+ # Retrieve the key before deleting because we depend on next_key
+ my $next_key = $self->next_key( $key );
+ $self->_engine->delete_key( $self, $key, $key );
+ $key = $next_key;
+ }
+ }
+ else {
+ my $size = $self->FETCHSIZE;
+ for my $key ( 0 .. $size - 1 ) {
+ $self->_engine->delete_key( $self, $key, $key );
+ }
+ $self->STORESIZE( 0 );
+ }
+
+ $self->unlock();
+
+ return 1;
+}
+
+##
+# Public method aliases
+##
+sub put { (shift)->STORE( @_ ) }
+sub store { (shift)->STORE( @_ ) }
+sub get { (shift)->FETCH( @_ ) }
+sub fetch { (shift)->FETCH( @_ ) }
+sub delete { (shift)->DELETE( @_ ) }
+sub exists { (shift)->EXISTS( @_ ) }
+sub clear { (shift)->CLEAR( @_ ) }
+
+package DBM::Deep::10002::Array;
+
+use 5.006_000;
+
+use strict;
+use warnings;
+
+our $VERSION = q(1.0002);
+
+# This is to allow DBM::Deep::10002::Array to handle negative indices on
+# its own. Otherwise, Perl would intercept the call to negative
+# indices for us. This was causing bugs for negative index handling.
+our $NEGATIVE_INDICES = 1;
+
+use base 'DBM::Deep::10002';
+
+use Scalar::Util ();
+
+sub _get_self {
+ eval { local $SIG{'__DIE__'}; tied( @{$_[0]} ) } || $_[0]
+}
+
+sub _repr { shift;[ @_ ] }
+
+sub _import {
+ my $self = shift;
+ my ($struct) = @_;
+
+ $self->push( @$struct );
+
+ return 1;
+}
+
+sub TIEARRAY {
+ my $class = shift;
+ my $args = $class->_get_args( @_ );
+
+ $args->{type} = $class->TYPE_ARRAY;
+
+ return $class->_init($args);
+}
+
+sub FETCH {
+ my $self = shift->_get_self;
+ my ($key) = @_;
+
+ $self->lock( $self->LOCK_SH );
+
+ if ( !defined $key ) {
+ DBM::Deep::10002->_throw_error( "Cannot use an undefined array index." );
+ }
+ elsif ( $key =~ /^-?\d+$/ ) {
+ if ( $key < 0 ) {
+ $key += $self->FETCHSIZE;
+ unless ( $key >= 0 ) {
+ $self->unlock;
+ return;
+ }
+ }
+ }
+ elsif ( $key ne 'length' ) {
+ $self->unlock;
+ DBM::Deep::10002->_throw_error( "Cannot use '$key' as an array index." );
+ }
+
+ my $rv = $self->SUPER::FETCH( $key );
+
+ $self->unlock;
+
+ return $rv;
+}
+
+sub STORE {
+ my $self = shift->_get_self;
+ my ($key, $value) = @_;
+
+ $self->lock( $self->LOCK_EX );
+
+ my $size;
+ my $idx_is_numeric;
+ if ( !defined $key ) {
+ DBM::Deep::10002->_throw_error( "Cannot use an undefined array index." );
+ }
+ elsif ( $key =~ /^-?\d+$/ ) {
+ $idx_is_numeric = 1;
+ if ( $key < 0 ) {
+ $size = $self->FETCHSIZE;
+ if ( $key + $size < 0 ) {
+ die( "Modification of non-creatable array value attempted, subscript $key" );
+ }
+ $key += $size
+ }
+ }
+ elsif ( $key ne 'length' ) {
+ $self->unlock;
+ DBM::Deep::10002->_throw_error( "Cannot use '$key' as an array index." );
+ }
+
+ my $rv = $self->SUPER::STORE( $key, $value );
+
+ if ( $idx_is_numeric ) {
+ $size = $self->FETCHSIZE unless defined $size;
+ if ( $key >= $size ) {
+ $self->STORESIZE( $key + 1 );
+ }
+ }
+
+ $self->unlock;
+
+ return $rv;
+}
+
+sub EXISTS {
+ my $self = shift->_get_self;
+ my ($key) = @_;
+
+ $self->lock( $self->LOCK_SH );
+
+ if ( !defined $key ) {
+ DBM::Deep::10002->_throw_error( "Cannot use an undefined array index." );
+ }
+ elsif ( $key =~ /^-?\d+$/ ) {
+ if ( $key < 0 ) {
+ $key += $self->FETCHSIZE;
+ unless ( $key >= 0 ) {
+ $self->unlock;
+ return;
+ }
+ }
+ }
+ elsif ( $key ne 'length' ) {
+ $self->unlock;
+ DBM::Deep::10002->_throw_error( "Cannot use '$key' as an array index." );
+ }
+
+ my $rv = $self->SUPER::EXISTS( $key );
+
+ $self->unlock;
+
+ return $rv;
+}
+
+sub DELETE {
+ my $self = shift->_get_self;
+ my ($key) = @_;
+
+ $self->lock( $self->LOCK_EX );
+
+ my $size = $self->FETCHSIZE;
+ if ( !defined $key ) {
+ DBM::Deep::10002->_throw_error( "Cannot use an undefined array index." );
+ }
+ elsif ( $key =~ /^-?\d+$/ ) {
+ if ( $key < 0 ) {
+ $key += $size;
+ unless ( $key >= 0 ) {
+ $self->unlock;
+ return;
+ }
+ }
+ }
+ elsif ( $key ne 'length' ) {
+ $self->unlock;
+ DBM::Deep::10002->_throw_error( "Cannot use '$key' as an array index." );
+ }
+
+ my $rv = $self->SUPER::DELETE( $key );
+
+ if ($rv && $key == $size - 1) {
+ $self->STORESIZE( $key );
+ }
+
+ $self->unlock;
+
+ return $rv;
+}
+
+# Now that we have a real Reference sector, we should store arrayzize there. However,
+# arraysize needs to be transactionally-aware, so a simple location to store it isn't
+# going to work.
+sub FETCHSIZE {
+ my $self = shift->_get_self;
+
+ $self->lock( $self->LOCK_SH );
+
+ my $SAVE_FILTER = $self->_storage->{filter_fetch_value};
+ $self->_storage->{filter_fetch_value} = undef;
+
+ my $size = $self->FETCH('length') || 0;
+
+ $self->_storage->{filter_fetch_value} = $SAVE_FILTER;
+
+ $self->unlock;
+
+ return $size;
+}
+
+sub STORESIZE {
+ my $self = shift->_get_self;
+ my ($new_length) = @_;
+
+ $self->lock( $self->LOCK_EX );
+
+ my $SAVE_FILTER = $self->_storage->{filter_store_value};
+ $self->_storage->{filter_store_value} = undef;
+
+ my $result = $self->STORE('length', $new_length, 'length');
+
+ $self->_storage->{filter_store_value} = $SAVE_FILTER;
+
+ $self->unlock;
+
+ return $result;
+}
+
+sub POP {
+ my $self = shift->_get_self;
+
+ $self->lock( $self->LOCK_EX );
+
+ my $length = $self->FETCHSIZE();
+
+ if ($length) {
+ my $content = $self->FETCH( $length - 1 );
+ $self->DELETE( $length - 1 );
+
+ $self->unlock;
+
+ return $content;
+ }
+ else {
+ $self->unlock;
+ return;
+ }
+}
+
+sub PUSH {
+ my $self = shift->_get_self;
+
+ $self->lock( $self->LOCK_EX );
+
+ my $length = $self->FETCHSIZE();
+
+ while (my $content = shift @_) {
+ $self->STORE( $length, $content );
+ $length++;
+ }
+
+ $self->unlock;
+
+ return $length;
+}
+
+# XXX This really needs to be something more direct within the file, not a
+# fetch and re-store. -RobK, 2007-09-20
+sub _move_value {
+ my $self = shift;
+ my ($old_key, $new_key) = @_;
+
+ my $val = $self->FETCH( $old_key );
+ if ( eval { local $SIG{'__DIE__'}; $val->isa( 'DBM::Deep::10002::Hash' ) } ) {
+ $self->STORE( $new_key, { %$val } );
+ }
+ elsif ( eval { local $SIG{'__DIE__'}; $val->isa( 'DBM::Deep::10002::Array' ) } ) {
+ $self->STORE( $new_key, [ @$val ] );
+ }
+ else {
+ $self->STORE( $new_key, $val );
+ }
+}
+
+sub SHIFT {
+ my $self = shift->_get_self;
+
+ $self->lock( $self->LOCK_EX );
+
+ my $length = $self->FETCHSIZE();
+
+ if ($length) {
+ my $content = $self->FETCH( 0 );
+
+ for (my $i = 0; $i < $length - 1; $i++) {
+ $self->_move_value( $i+1, $i );
+ }
+ $self->DELETE( $length - 1 );
+
+ $self->unlock;
+
+ return $content;
+ }
+ else {
+ $self->unlock;
+ return;
+ }
+}
+
+sub UNSHIFT {
+ my $self = shift->_get_self;
+ my @new_elements = @_;
+
+ $self->lock( $self->LOCK_EX );
+
+ my $length = $self->FETCHSIZE();
+ my $new_size = scalar @new_elements;
+
+ if ($length) {
+ for (my $i = $length - 1; $i >= 0; $i--) {
+ $self->_move_value( $i, $i+$new_size );
+ }
+ }
+
+ for (my $i = 0; $i < $new_size; $i++) {
+ $self->STORE( $i, $new_elements[$i] );
+ }
+
+ $self->unlock;
+
+ return $length + $new_size;
+}
+
+sub SPLICE {
+ my $self = shift->_get_self;
+
+ $self->lock( $self->LOCK_EX );
+
+ my $length = $self->FETCHSIZE();
+
+ ##
+ # Calculate offset and length of splice
+ ##
+ my $offset = shift;
+ $offset = 0 unless defined $offset;
+ if ($offset < 0) { $offset += $length; }
+
+ my $splice_length;
+ if (scalar @_) { $splice_length = shift; }
+ else { $splice_length = $length - $offset; }
+ if ($splice_length < 0) { $splice_length += ($length - $offset); }
+
+ ##
+ # Setup array with new elements, and copy out old elements for return
+ ##
+ my @new_elements = @_;
+ my $new_size = scalar @new_elements;
+
+ my @old_elements = map {
+ $self->FETCH( $_ )
+ } $offset .. ($offset + $splice_length - 1);
+
+ ##
+ # Adjust array length, and shift elements to accomodate new section.
+ ##
+ if ( $new_size != $splice_length ) {
+ if ($new_size > $splice_length) {
+ for (my $i = $length - 1; $i >= $offset + $splice_length; $i--) {
+ $self->_move_value( $i, $i + ($new_size - $splice_length) );
+ }
+ }
+ else {
+ for (my $i = $offset + $splice_length; $i < $length; $i++) {
+ $self->_move_value( $i, $i + ($new_size - $splice_length) );
+ }
+ for (my $i = 0; $i < $splice_length - $new_size; $i++) {
+ $self->DELETE( $length - 1 );
+ $length--;
+ }
+ }
+ }
+
+ ##
+ # Insert new elements into array
+ ##
+ for (my $i = $offset; $i < $offset + $new_size; $i++) {
+ $self->STORE( $i, shift @new_elements );
+ }
+
+ $self->unlock;
+
+ ##
+ # Return deleted section, or last element in scalar context.
+ ##
+ return wantarray ? @old_elements : $old_elements[-1];
+}
+
+# We don't need to populate it, yet.
+# It will be useful, though, when we split out HASH and ARRAY
+sub EXTEND {
+ ##
+ # Perl will call EXTEND() when the array is likely to grow.
+ # We don't care, but include it because it gets called at times.
+ ##
+}
+
+sub _copy_node {
+ my $self = shift;
+ my ($db_temp) = @_;
+
+ my $length = $self->length();
+ for (my $index = 0; $index < $length; $index++) {
+ my $value = $self->get($index);
+ $self->_copy_value( \$db_temp->[$index], $value );
+ }
+
+ return 1;
+}
+
+##
+# Public method aliases
+##
+sub length { (shift)->FETCHSIZE(@_) }
+sub pop { (shift)->POP(@_) }
+sub push { (shift)->PUSH(@_) }
+sub unshift { (shift)->UNSHIFT(@_) }
+sub splice { (shift)->SPLICE(@_) }
+
+# This must be last otherwise we have to qualify all other calls to shift
+# as calls to CORE::shift
+sub shift { (CORE::shift)->SHIFT(@_) }
+
+package DBM::Deep::10002::Hash;
+
+use 5.006_000;
+
+use strict;
+use warnings;
+
+our $VERSION = q(1.0002);
+
+use base 'DBM::Deep::10002';
+
+sub _get_self {
+ eval { local $SIG{'__DIE__'}; tied( %{$_[0]} ) } || $_[0]
+}
+
+#XXX Need to add a check here for @_ % 2
+sub _repr { shift;return { @_ } }
+
+sub _import {
+ my $self = shift;
+ my ($struct) = @_;
+
+ foreach my $key (keys %$struct) {
+ $self->put($key, $struct->{$key});
+ }
+
+ return 1;
+}
+
+sub TIEHASH {
+ ##
+ # Tied hash constructor method, called by Perl's tie() function.
+ ##
+ my $class = shift;
+ my $args = $class->_get_args( @_ );
+
+ $args->{type} = $class->TYPE_HASH;
+
+ return $class->_init($args);
+}
+
+sub FETCH {
+ my $self = shift->_get_self;
+ DBM::Deep::10002->_throw_error( "Cannot use an undefined hash key." ) unless defined $_[0];
+ my $key = ($self->_storage->{filter_store_key})
+ ? $self->_storage->{filter_store_key}->($_[0])
+ : $_[0];
+
+ return $self->SUPER::FETCH( $key, $_[0] );
+}
+
+sub STORE {
+ my $self = shift->_get_self;
+ DBM::Deep::10002->_throw_error( "Cannot use an undefined hash key." ) unless defined $_[0];
+ my $key = ($self->_storage->{filter_store_key})
+ ? $self->_storage->{filter_store_key}->($_[0])
+ : $_[0];
+ my $value = $_[1];
+
+ return $self->SUPER::STORE( $key, $value, $_[0] );
+}
+
+sub EXISTS {
+ my $self = shift->_get_self;
+ DBM::Deep::10002->_throw_error( "Cannot use an undefined hash key." ) unless defined $_[0];
+ my $key = ($self->_storage->{filter_store_key})
+ ? $self->_storage->{filter_store_key}->($_[0])
+ : $_[0];
+
+ return $self->SUPER::EXISTS( $key );
+}
+
+sub DELETE {
+ my $self = shift->_get_self;
+ DBM::Deep::10002->_throw_error( "Cannot use an undefined hash key." ) unless defined $_[0];
+ my $key = ($self->_storage->{filter_store_key})
+ ? $self->_storage->{filter_store_key}->($_[0])
+ : $_[0];
+
+ return $self->SUPER::DELETE( $key, $_[0] );
+}
+
+sub FIRSTKEY {
+ ##
+ # Locate and return first key (in no particular order)
+ ##
+ my $self = shift->_get_self;
+
+ ##
+ # Request shared lock for reading
+ ##
+ $self->lock( $self->LOCK_SH );
+
+ my $result = $self->_engine->get_next_key( $self );
+
+ $self->unlock();
+
+ return ($result && $self->_storage->{filter_fetch_key})
+ ? $self->_storage->{filter_fetch_key}->($result)
+ : $result;
+}
+
+sub NEXTKEY {
+ ##
+ # Return next key (in no particular order), given previous one
+ ##
+ my $self = shift->_get_self;
+
+ my $prev_key = ($self->_storage->{filter_store_key})
+ ? $self->_storage->{filter_store_key}->($_[0])
+ : $_[0];
+
+ ##
+ # Request shared lock for reading
+ ##
+ $self->lock( $self->LOCK_SH );
+
+ my $result = $self->_engine->get_next_key( $self, $prev_key );
+
+ $self->unlock();
+
+ return ($result && $self->_storage->{filter_fetch_key})
+ ? $self->_storage->{filter_fetch_key}->($result)
+ : $result;
+}
+
+##
+# Public method aliases
+##
+sub first_key { (shift)->FIRSTKEY(@_) }
+sub next_key { (shift)->NEXTKEY(@_) }
+
+sub _copy_node {
+ my $self = shift;
+ my ($db_temp) = @_;
+
+ my $key = $self->first_key();
+ while ($key) {
+ my $value = $self->get($key);
+ $self->_copy_value( \$db_temp->{$key}, $value );
+ $key = $self->next_key($key);
+ }
+
+ return 1;
+}
+
+package DBM::Deep::10002::File;
+
+use 5.006_000;
+
+use strict;
+use warnings;
+
+our $VERSION = q(1.0002);
+
+use Fcntl qw( :DEFAULT :flock :seek );
+
+sub new {
+ my $class = shift;
+ my ($args) = @_;
+
+ my $self = bless {
+ autobless => 1,
+ autoflush => 1,
+ end => 0,
+ fh => undef,
+ file => undef,
+ file_offset => 0,
+ locking => 1,
+ locked => 0,
+#XXX Migrate this to the engine, where it really belongs.
+ filter_store_key => undef,
+ filter_store_value => undef,
+ filter_fetch_key => undef,
+ filter_fetch_value => undef,
+ }, $class;
+
+ # Grab the parameters we want to use
+ foreach my $param ( keys %$self ) {
+ next unless exists $args->{$param};
+ $self->{$param} = $args->{$param};
+ }
+
+ if ( $self->{fh} && !$self->{file_offset} ) {
+ $self->{file_offset} = tell( $self->{fh} );
+ }
+
+ $self->open unless $self->{fh};
+
+ return $self;
+}
+
+sub open {
+ my $self = shift;
+
+ # Adding O_BINARY should remove the need for the binmode below. However,
+ # I'm not going to remove it because I don't have the Win32 chops to be
+ # absolutely certain everything will be ok.
+ my $flags = O_CREAT | O_BINARY;
+
+ if ( !-e $self->{file} || -w _ ) {
+ $flags |= O_RDWR;
+ }
+ else {
+ $flags |= O_RDONLY;
+ }
+
+ my $fh;
+ sysopen( $fh, $self->{file}, $flags )
+ or die "DBM::Deep::10002: Cannot sysopen file '$self->{file}': $!\n";
+ $self->{fh} = $fh;
+
+ # Even though we use O_BINARY, better be safe than sorry.
+ binmode $fh;
+
+ if ($self->{autoflush}) {
+ my $old = select $fh;
+ $|=1;
+ select $old;
+ }
+
+ return 1;
+}
+
+sub close {
+ my $self = shift;
+
+ if ( $self->{fh} ) {
+ close $self->{fh};
+ $self->{fh} = undef;
+ }
+
+ return 1;
+}
+
+sub set_inode {
+ my $self = shift;
+
+ unless ( defined $self->{inode} ) {
+ my @stats = stat($self->{fh});
+ $self->{inode} = $stats[1];
+ $self->{end} = $stats[7];
+ }
+
+ return 1;
+}
+
+sub print_at {
+ my $self = shift;
+ my $loc = shift;
+
+ local ($/,$\);
+
+ my $fh = $self->{fh};
+ if ( defined $loc ) {
+ seek( $fh, $loc + $self->{file_offset}, SEEK_SET );
+ }
+
+ print( $fh @_ );
+
+ return 1;
+}
+
+sub read_at {
+ my $self = shift;
+ my ($loc, $size) = @_;
+
+ local ($/,$\);
+
+ my $fh = $self->{fh};
+ if ( defined $loc ) {
+ seek( $fh, $loc + $self->{file_offset}, SEEK_SET );
+ }
+
+ my $buffer;
+ read( $fh, $buffer, $size);
+
+ return $buffer;
+}
+
+sub DESTROY {
+ my $self = shift;
+ return unless $self;
+
+ $self->close;
+
+ return;
+}
+
+sub request_space {
+ my $self = shift;
+ my ($size) = @_;
+
+ #XXX Do I need to reset $self->{end} here? I need a testcase
+ my $loc = $self->{end};
+ $self->{end} += $size;
+
+ return $loc;
+}
+
+##
+# If db locking is set, flock() the db file. If called multiple
+# times before unlock(), then the same number of unlocks() must
+# be called before the lock is released.
+##
+sub lock {
+ my $self = shift;
+ my ($obj, $type) = @_;
+
+ $type = LOCK_EX unless defined $type;
+
+ if (!defined($self->{fh})) { return; }
+
+ if ($self->{locking}) {
+ if (!$self->{locked}) {
+ flock($self->{fh}, $type);
+
+ # refresh end counter in case file has changed size
+ my @stats = stat($self->{fh});
+ $self->{end} = $stats[7];
+
+ # double-check file inode, in case another process
+ # has optimize()d our file while we were waiting.
+ if (defined($self->{inode}) && $stats[1] != $self->{inode}) {
+ $self->close;
+ $self->open;
+
+ #XXX This needs work
+ $obj->{engine}->setup_fh( $obj );
+
+ flock($self->{fh}, $type); # re-lock
+
+ # This may not be necessary after re-opening
+ $self->{end} = (stat($self->{fh}))[7]; # re-end
+ }
+ }
+ $self->{locked}++;
+
+ return 1;
+ }
+
+ return;
+}
+
+##
+# If db locking is set, unlock the db file. See note in lock()
+# regarding calling lock() multiple times.
+##
+sub unlock {
+ my $self = shift;
+
+ if (!defined($self->{fh})) { return; }
+
+ if ($self->{locking} && $self->{locked} > 0) {
+ $self->{locked}--;
+ if (!$self->{locked}) { flock($self->{fh}, LOCK_UN); }
+
+ return 1;
+ }
+
+ return;
+}
+
+sub flush {
+ my $self = shift;
+
+ # Flush the filehandle
+ my $old_fh = select $self->{fh};
+ my $old_af = $|; $| = 1; $| = $old_af;
+ select $old_fh;
+
+ return 1;
+}
+
+package DBM::Deep::10002::Engine;
+
+use 5.006_000;
+
+use strict;
+use warnings;
+
+our $VERSION = q(1.0002);
+
+use Scalar::Util ();
+
+# File-wide notes:
+# * Every method in here assumes that the storage has been appropriately
+# safeguarded. This can be anything from flock() to some sort of manual
+# mutex. But, it's the caller's responsability to make sure that this has
+# been done.
+
+# Setup file and tag signatures. These should never change.
+sub SIG_FILE () { 'DPDB' }
+sub SIG_HEADER () { 'h' }
+sub SIG_HASH () { 'H' }
+sub SIG_ARRAY () { 'A' }
+sub SIG_NULL () { 'N' }
+sub SIG_DATA () { 'D' }
+sub SIG_INDEX () { 'I' }
+sub SIG_BLIST () { 'B' }
+sub SIG_FREE () { 'F' }
+sub SIG_SIZE () { 1 }
+
+my $STALE_SIZE = 2;
+
+# Please refer to the pack() documentation for further information
+my %StP = (
+ 1 => 'C', # Unsigned char value (no order needed as it's just one byte)
+ 2 => 'n', # Unsigned short in "network" (big-endian) order
+ 4 => 'N', # Unsigned long in "network" (big-endian) order
+ 8 => 'Q', # Usigned quad (no order specified, presumably machine-dependent)
+);
+
+################################################################################
+
+sub new {
+ my $class = shift;
+ my ($args) = @_;
+
+ my $self = bless {
+ byte_size => 4,
+
+ digest => undef,
+ hash_size => 16, # In bytes
+ hash_chars => 256, # Number of chars the algorithm uses per byte
+ max_buckets => 16,
+ num_txns => 1, # The HEAD
+ trans_id => 0, # Default to the HEAD
+
+ data_sector_size => 64, # Size in bytes of each data sector
+
+ entries => {}, # This is the list of entries for transactions
+ storage => undef,
+ }, $class;
+
+ # Never allow byte_size to be set directly.
+ delete $args->{byte_size};
+ if ( defined $args->{pack_size} ) {
+ if ( lc $args->{pack_size} eq 'small' ) {
+ $args->{byte_size} = 2;
+ }
+ elsif ( lc $args->{pack_size} eq 'medium' ) {
+ $args->{byte_size} = 4;
+ }
+ elsif ( lc $args->{pack_size} eq 'large' ) {
+ $args->{byte_size} = 8;
+ }
+ else {
+ DBM::Deep::10002->_throw_error( "Unknown pack_size value: '$args->{pack_size}'" );
+ }
+ }
+
+ # Grab the parameters we want to use
+ foreach my $param ( keys %$self ) {
+ next unless exists $args->{$param};
+ $self->{$param} = $args->{$param};
+ }
+
+ my %validations = (
+ max_buckets => { floor => 16, ceil => 256 },
+ num_txns => { floor => 1, ceil => 255 },
+ data_sector_size => { floor => 32, ceil => 256 },
+ );
+
+ while ( my ($attr, $c) = each %validations ) {
+ if ( !defined $self->{$attr}
+ || !length $self->{$attr}
+ || $self->{$attr} =~ /\D/
+ || $self->{$attr} < $c->{floor}
+ ) {
+ $self->{$attr} = '(undef)' if !defined $self->{$attr};
+ warn "Floor of $attr is $c->{floor}. Setting it to $c->{floor} from '$self->{$attr}'\n";
+ $self->{$attr} = $c->{floor};
+ }
+ elsif ( $self->{$attr} > $c->{ceil} ) {
+ warn "Ceiling of $attr is $c->{ceil}. Setting it to $c->{ceil} from '$self->{$attr}'\n";
+ $self->{$attr} = $c->{ceil};
+ }
+ }
+
+ if ( !$self->{digest} ) {
+ require Digest::MD5;
+ $self->{digest} = \&Digest::MD5::md5;
+ }
+
+ return $self;
+}
+
+################################################################################
+
+sub read_value {
+ my $self = shift;
+ my ($obj, $key) = @_;
+
+ # This will be a Reference sector
+ my $sector = $self->_load_sector( $obj->_base_offset )
+ or return;
+
+ if ( $sector->staleness != $obj->_staleness ) {
+ return;
+ }
+
+ my $key_md5 = $self->_apply_digest( $key );
+
+ my $value_sector = $sector->get_data_for({
+ key_md5 => $key_md5,
+ allow_head => 1,
+ });
+
+ unless ( $value_sector ) {
+ $value_sector = DBM::Deep::10002::Engine::Sector::Null->new({
+ engine => $self,
+ data => undef,
+ });
+
+ $sector->write_data({
+ key_md5 => $key_md5,
+ key => $key,
+ value => $value_sector,
+ });
+ }
+
+ return $value_sector->data;
+}
+
+sub get_classname {
+ my $self = shift;
+ my ($obj) = @_;
+
+ # This will be a Reference sector
+ my $sector = $self->_load_sector( $obj->_base_offset )
+ or DBM::Deep::10002->_throw_error( "How did get_classname fail (no sector for '$obj')?!" );
+
+ if ( $sector->staleness != $obj->_staleness ) {
+ return;
+ }
+
+ return $sector->get_classname;
+}
+
+sub key_exists {
+ my $self = shift;
+ my ($obj, $key) = @_;
+
+ # This will be a Reference sector
+ my $sector = $self->_load_sector( $obj->_base_offset )
+ or return '';
+
+ if ( $sector->staleness != $obj->_staleness ) {
+ return '';
+ }
+
+ my $data = $sector->get_data_for({
+ key_md5 => $self->_apply_digest( $key ),
+ allow_head => 1,
+ });
+
+ # exists() returns 1 or '' for true/false.
+ return $data ? 1 : '';
+}
+
+sub delete_key {
+ my $self = shift;
+ my ($obj, $key) = @_;
+
+ my $sector = $self->_load_sector( $obj->_base_offset )
+ or return;
+
+ if ( $sector->staleness != $obj->_staleness ) {
+ return;
+ }
+
+ return $sector->delete_key({
+ key_md5 => $self->_apply_digest( $key ),
+ allow_head => 0,
+ });
+}
+
+sub write_value {
+ my $self = shift;
+ my ($obj, $key, $value) = @_;
+
+ my $r = Scalar::Util::reftype( $value ) || '';
+ {
+ last if $r eq '';
+ last if $r eq 'HASH';
+ last if $r eq 'ARRAY';
+
+ DBM::Deep::10002->_throw_error(
+ "Storage of references of type '$r' is not supported."
+ );
+ }
+
+ my ($class, $type);
+ if ( !defined $value ) {
+ $class = 'DBM::Deep::10002::Engine::Sector::Null';
+ }
+ elsif ( $r eq 'ARRAY' || $r eq 'HASH' ) {
+ if ( $r eq 'ARRAY' && tied(@$value) ) {
+ DBM::Deep::10002->_throw_error( "Cannot store something that is tied." );
+ }
+ if ( $r eq 'HASH' && tied(%$value) ) {
+ DBM::Deep::10002->_throw_error( "Cannot store something that is tied." );
+ }
+ $class = 'DBM::Deep::10002::Engine::Sector::Reference';
+ $type = substr( $r, 0, 1 );
+ }
+ else {
+ $class = 'DBM::Deep::10002::Engine::Sector::Scalar';
+ }
+
+ # This will be a Reference sector
+ my $sector = $self->_load_sector( $obj->_base_offset )
+ or DBM::Deep::10002->_throw_error( "Cannot write to a deleted spot in DBM::Deep::10002." );
+
+ if ( $sector->staleness != $obj->_staleness ) {
+ DBM::Deep::10002->_throw_error( "Cannot write to a deleted spot in DBM::Deep::10002.n" );
+ }
+
+ # Create this after loading the reference sector in case something bad happens.
+ # This way, we won't allocate value sector(s) needlessly.
+ my $value_sector = $class->new({
+ engine => $self,
+ data => $value,
+ type => $type,
+ });
+
+ $sector->write_data({
+ key => $key,
+ key_md5 => $self->_apply_digest( $key ),
+ value => $value_sector,
+ });
+
+ # This code is to make sure we write all the values in the $value to the disk
+ # and to make sure all changes to $value after the assignment are reflected
+ # on disk. This may be counter-intuitive at first, but it is correct dwimmery.
+ # NOTE - simply tying $value won't perform a STORE on each value. Hence, the
+ # copy to a temp value.
+ if ( $r eq 'ARRAY' ) {
+ my @temp = @$value;
+ tie @$value, 'DBM::Deep::10002', {
+ base_offset => $value_sector->offset,
+ staleness => $value_sector->staleness,
+ storage => $self->storage,
+ engine => $self,
+ };
+ @$value = @temp;
+ bless $value, 'DBM::Deep::10002::Array' unless Scalar::Util::blessed( $value );
+ }
+ elsif ( $r eq 'HASH' ) {
+ my %temp = %$value;
+ tie %$value, 'DBM::Deep::10002', {
+ base_offset => $value_sector->offset,
+ staleness => $value_sector->staleness,
+ storage => $self->storage,
+ engine => $self,
+ };
+
+ %$value = %temp;
+ bless $value, 'DBM::Deep::10002::Hash' unless Scalar::Util::blessed( $value );
+ }
+
+ return 1;
+}
+
+# XXX Add staleness here
+sub get_next_key {
+ my $self = shift;
+ my ($obj, $prev_key) = @_;
+
+ # XXX Need to add logic about resetting the iterator if any key in the reference has changed
+ unless ( $prev_key ) {
+ $obj->{iterator} = DBM::Deep::10002::Iterator->new({
+ base_offset => $obj->_base_offset,
+ engine => $self,
+ });
+ }
+
+ return $obj->{iterator}->get_next_key( $obj );
+}
+
+################################################################################
+
+sub setup_fh {
+ my $self = shift;
+ my ($obj) = @_;
+
+ # We're opening the file.
+ unless ( $obj->_base_offset ) {
+ my $bytes_read = $self->_read_file_header;
+
+ # Creating a new file
+ unless ( $bytes_read ) {
+ $self->_write_file_header;
+
+ # 1) Create Array/Hash entry
+ my $initial_reference = DBM::Deep::10002::Engine::Sector::Reference->new({
+ engine => $self,
+ type => $obj->_type,
+ });
+ $obj->{base_offset} = $initial_reference->offset;
+ $obj->{staleness} = $initial_reference->staleness;
+
+ $self->storage->flush;
+ }
+ # Reading from an existing file
+ else {
+ $obj->{base_offset} = $bytes_read;
+ my $initial_reference = DBM::Deep::10002::Engine::Sector::Reference->new({
+ engine => $self,
+ offset => $obj->_base_offset,
+ });
+ unless ( $initial_reference ) {
+ DBM::Deep::10002->_throw_error("Corrupted file, no master index record");
+ }
+
+ unless ($obj->_type eq $initial_reference->type) {
+ DBM::Deep::10002->_throw_error("File type mismatch");
+ }
+
+ $obj->{staleness} = $initial_reference->staleness;
+ }
+ }
+
+ return 1;
+}
+
+sub begin_work {
+ my $self = shift;
+ my ($obj) = @_;
+
+ if ( $self->trans_id ) {
+ DBM::Deep::10002->_throw_error( "Cannot begin_work within an active transaction" );
+ }
+
+ my @slots = $self->read_txn_slots;
+ my $found;
+ for my $i ( 0 .. $#slots ) {
+ next if $slots[$i];
+
+ $slots[$i] = 1;
+ $self->set_trans_id( $i + 1 );
+ $found = 1;
+ last;
+ }
+ unless ( $found ) {
+ DBM::Deep::10002->_throw_error( "Cannot allocate transaction ID" );
+ }
+ $self->write_txn_slots( @slots );
+
+ if ( !$self->trans_id ) {
+ DBM::Deep::10002->_throw_error( "Cannot begin_work - no available transactions" );
+ }
+
+ return;
+}
+
+sub rollback {
+ my $self = shift;
+ my ($obj) = @_;
+
+ if ( !$self->trans_id ) {
+ DBM::Deep::10002->_throw_error( "Cannot rollback without an active transaction" );
+ }
+
+ # Each entry is the file location for a bucket that has a modification for
+ # this transaction. The entries need to be expunged.
+ foreach my $entry (@{ $self->get_entries } ) {
+ # Remove the entry here
+ my $read_loc = $entry
+ + $self->hash_size
+ + $self->byte_size
+ + $self->byte_size
+ + ($self->trans_id - 1) * ( $self->byte_size + $STALE_SIZE );
+
+ my $data_loc = $self->storage->read_at( $read_loc, $self->byte_size );
+ $data_loc = unpack( $StP{$self->byte_size}, $data_loc );
+ $self->storage->print_at( $read_loc, pack( $StP{$self->byte_size}, 0 ) );
+
+ if ( $data_loc > 1 ) {
+ $self->_load_sector( $data_loc )->free;
+ }
+ }
+
+ $self->clear_entries;
+
+ my @slots = $self->read_txn_slots;
+ $slots[$self->trans_id-1] = 0;
+ $self->write_txn_slots( @slots );
+ $self->inc_txn_staleness_counter( $self->trans_id );
+ $self->set_trans_id( 0 );
+
+ return 1;
+}
+
+sub commit {
+ my $self = shift;
+ my ($obj) = @_;
+
+ if ( !$self->trans_id ) {
+ DBM::Deep::10002->_throw_error( "Cannot commit without an active transaction" );
+ }
+
+ foreach my $entry (@{ $self->get_entries } ) {
+ # Overwrite the entry in head with the entry in trans_id
+ my $base = $entry
+ + $self->hash_size
+ + $self->byte_size;
+
+ my $head_loc = $self->storage->read_at( $base, $self->byte_size );
+ $head_loc = unpack( $StP{$self->byte_size}, $head_loc );
+
+ my $spot = $base + $self->byte_size + ($self->trans_id - 1) * ( $self->byte_size + $STALE_SIZE );
+ my $trans_loc = $self->storage->read_at(
+ $spot, $self->byte_size,
+ );
+
+ $self->storage->print_at( $base, $trans_loc );
+ $self->storage->print_at(
+ $spot,
+ pack( $StP{$self->byte_size} . ' ' . $StP{$STALE_SIZE}, (0) x 2 ),
+ );
+
+ if ( $head_loc > 1 ) {
+ $self->_load_sector( $head_loc )->free;
+ }
+ }
+
+ $self->clear_entries;
+
+ my @slots = $self->read_txn_slots;
+ $slots[$self->trans_id-1] = 0;
+ $self->write_txn_slots( @slots );
+ $self->inc_txn_staleness_counter( $self->trans_id );
+ $self->set_trans_id( 0 );
+
+ return 1;
+}
+
+sub read_txn_slots {
+ my $self = shift;
+ my $bl = $self->txn_bitfield_len;
+ my $num_bits = $bl * 8;
+ return split '', unpack( 'b'.$num_bits,
+ $self->storage->read_at(
+ $self->trans_loc, $bl,
+ )
+ );
+}
+
+sub write_txn_slots {
+ my $self = shift;
+ my $num_bits = $self->txn_bitfield_len * 8;
+ $self->storage->print_at( $self->trans_loc,
+ pack( 'b'.$num_bits, join('', @_) ),
+ );
+}
+
+sub get_running_txn_ids {
+ my $self = shift;
+ my @transactions = $self->read_txn_slots;
+ my @trans_ids = map { $_+1} grep { $transactions[$_] } 0 .. $#transactions;
+}
+
+sub get_txn_staleness_counter {
+ my $self = shift;
+ my ($trans_id) = @_;
+
+ # Hardcode staleness of 0 for the HEAD
+ return 0 unless $trans_id;
+
+ return unpack( $StP{$STALE_SIZE},
+ $self->storage->read_at(
+ $self->trans_loc + 4 + $STALE_SIZE * ($trans_id - 1),
+ 4,
+ )
+ );
+}
+
+sub inc_txn_staleness_counter {
+ my $self = shift;
+ my ($trans_id) = @_;
+
+ # Hardcode staleness of 0 for the HEAD
+ return unless $trans_id;
+
+ $self->storage->print_at(
+ $self->trans_loc + 4 + $STALE_SIZE * ($trans_id - 1),
+ pack( $StP{$STALE_SIZE}, $self->get_txn_staleness_counter( $trans_id ) + 1 ),
+ );
+}
+
+sub get_entries {
+ my $self = shift;
+ return [ keys %{ $self->{entries}{$self->trans_id} ||= {} } ];
+}
+
+sub add_entry {
+ my $self = shift;
+ my ($trans_id, $loc) = @_;
+
+ $self->{entries}{$trans_id} ||= {};
+ $self->{entries}{$trans_id}{$loc} = undef;
+}
+
+# If the buckets are being relocated because of a reindexing, the entries
+# mechanism needs to be made aware of it.
+sub reindex_entry {
+ my $self = shift;
+ my ($old_loc, $new_loc) = @_;
+
+ TRANS:
+ while ( my ($trans_id, $locs) = each %{ $self->{entries} } ) {
+ foreach my $orig_loc ( keys %{ $locs } ) {
+ if ( $orig_loc == $old_loc ) {
+ delete $locs->{orig_loc};
+ $locs->{$new_loc} = undef;
+ next TRANS;
+ }
+ }
+ }
+}
+
+sub clear_entries {
+ my $self = shift;
+ delete $self->{entries}{$self->trans_id};
+}
+
+################################################################################
+
+{
+ my $header_fixed = length( SIG_FILE ) + 1 + 4 + 4;
+ my $this_file_version = 2;
+
+ sub _write_file_header {
+ my $self = shift;
+
+ my $nt = $self->num_txns;
+ my $bl = $self->txn_bitfield_len;
+
+ my $header_var = 1 + 1 + 1 + 1 + $bl + $STALE_SIZE * ($nt - 1) + 3 * $self->byte_size;
+
+ my $loc = $self->storage->request_space( $header_fixed + $header_var );
+
+ $self->storage->print_at( $loc,
+ SIG_FILE,
+ SIG_HEADER,
+ pack('N', $this_file_version), # At this point, we're at 9 bytes
+ pack('N', $header_var), # header size
+ # --- Above is $header_fixed. Below is $header_var
+ pack('C', $self->byte_size),
+
+ # These shenanigans are to allow a 256 within a C
+ pack('C', $self->max_buckets - 1),
+ pack('C', $self->data_sector_size - 1),
+
+ pack('C', $nt),
+ pack('C' . $bl, 0 ), # Transaction activeness bitfield
+ pack($StP{$STALE_SIZE}.($nt-1), 0 x ($nt-1) ), # Transaction staleness counters
+ pack($StP{$self->byte_size}, 0), # Start of free chain (blist size)
+ pack($StP{$self->byte_size}, 0), # Start of free chain (data size)
+ pack($StP{$self->byte_size}, 0), # Start of free chain (index size)
+ );
+
+ #XXX Set these less fragilely
+ $self->set_trans_loc( $header_fixed + 4 );
+ $self->set_chains_loc( $header_fixed + 4 + $bl + $STALE_SIZE * ($nt-1) );
+
+ return;
+ }
+
+ sub _read_file_header {
+ my $self = shift;
+
+ my $buffer = $self->storage->read_at( 0, $header_fixed );
+ return unless length($buffer);
+
+ my ($file_signature, $sig_header, $file_version, $size) = unpack(
+ 'A4 A N N', $buffer
+ );
+
+ unless ( $file_signature eq SIG_FILE ) {
+ $self->storage->close;
+ DBM::Deep::10002->_throw_error( "Signature not found -- file is not a Deep DB" );
+ }
+
+ unless ( $sig_header eq SIG_HEADER ) {
+ $self->storage->close;
+ DBM::Deep::10002->_throw_error( "Pre-1.00 file version found" );
+ }
+
+ unless ( $file_version == $this_file_version ) {
+ $self->storage->close;
+ DBM::Deep::10002->_throw_error(
+ "Wrong file version found - " . $file_version .
+ " - expected " . $this_file_version
+ );
+ }
+
+ my $buffer2 = $self->storage->read_at( undef, $size );
+ my @values = unpack( 'C C C C', $buffer2 );
+
+ if ( @values != 4 || grep { !defined } @values ) {
+ $self->storage->close;
+ DBM::Deep::10002->_throw_error("Corrupted file - bad header");
+ }
+
+ #XXX Add warnings if values weren't set right
+ @{$self}{qw(byte_size max_buckets data_sector_size num_txns)} = @values;
+
+ # These shenangians are to allow a 256 within a C
+ $self->{max_buckets} += 1;
+ $self->{data_sector_size} += 1;
+
+ my $bl = $self->txn_bitfield_len;
+
+ my $header_var = scalar(@values) + $bl + $STALE_SIZE * ($self->num_txns - 1) + 3 * $self->byte_size;
+ unless ( $size == $header_var ) {
+ $self->storage->close;
+ DBM::Deep::10002->_throw_error( "Unexpected size found ($size <-> $header_var)." );
+ }
+
+ $self->set_trans_loc( $header_fixed + scalar(@values) );
+ $self->set_chains_loc( $header_fixed + scalar(@values) + $bl + $STALE_SIZE * ($self->num_txns - 1) );
+
+ return length($buffer) + length($buffer2);
+ }
+}
+
+sub _load_sector {
+ my $self = shift;
+ my ($offset) = @_;
+
+ # Add a catch for offset of 0 or 1
+ return if $offset <= 1;
+
+ my $type = $self->storage->read_at( $offset, 1 );
+ return if $type eq chr(0);
+
+ if ( $type eq $self->SIG_ARRAY || $type eq $self->SIG_HASH ) {
+ return DBM::Deep::10002::Engine::Sector::Reference->new({
+ engine => $self,
+ type => $type,
+ offset => $offset,
+ });
+ }
+ # XXX Don't we need key_md5 here?
+ elsif ( $type eq $self->SIG_BLIST ) {
+ return DBM::Deep::10002::Engine::Sector::BucketList->new({
+ engine => $self,
+ type => $type,
+ offset => $offset,
+ });
+ }
+ elsif ( $type eq $self->SIG_INDEX ) {
+ return DBM::Deep::10002::Engine::Sector::Index->new({
+ engine => $self,
+ type => $type,
+ offset => $offset,
+ });
+ }
+ elsif ( $type eq $self->SIG_NULL ) {
+ return DBM::Deep::10002::Engine::Sector::Null->new({
+ engine => $self,
+ type => $type,
+ offset => $offset,
+ });
+ }
+ elsif ( $type eq $self->SIG_DATA ) {
+ return DBM::Deep::10002::Engine::Sector::Scalar->new({
+ engine => $self,
+ type => $type,
+ offset => $offset,
+ });
+ }
+ # This was deleted from under us, so just return and let the caller figure it out.
+ elsif ( $type eq $self->SIG_FREE ) {
+ return;
+ }
+
+ DBM::Deep::10002->_throw_error( "'$offset': Don't know what to do with type '$type'" );
+}
+
+sub _apply_digest {
+ my $self = shift;
+ return $self->{digest}->(@_);
+}
+
+sub _add_free_blist_sector { shift->_add_free_sector( 0, @_ ) }
+sub _add_free_data_sector { shift->_add_free_sector( 1, @_ ) }
+sub _add_free_index_sector { shift->_add_free_sector( 2, @_ ) }
+
+sub _add_free_sector {
+ my $self = shift;
+ my ($multiple, $offset, $size) = @_;
+
+ my $chains_offset = $multiple * $self->byte_size;
+
+ my $storage = $self->storage;
+
+ # Increment staleness.
+ # XXX Can this increment+modulo be done by "&= 0x1" ?
+ my $staleness = unpack( $StP{$STALE_SIZE}, $storage->read_at( $offset + SIG_SIZE, $STALE_SIZE ) );
+ $staleness = ($staleness + 1 ) % ( 2 ** ( 8 * $STALE_SIZE ) );
+ $storage->print_at( $offset + SIG_SIZE, pack( $StP{$STALE_SIZE}, $staleness ) );
+
+ my $old_head = $storage->read_at( $self->chains_loc + $chains_offset, $self->byte_size );
+
+ $storage->print_at( $self->chains_loc + $chains_offset,
+ pack( $StP{$self->byte_size}, $offset ),
+ );
+
+ # Record the old head in the new sector after the signature and staleness counter
+ $storage->print_at( $offset + SIG_SIZE + $STALE_SIZE, $old_head );
+}
+
+sub _request_blist_sector { shift->_request_sector( 0, @_ ) }
+sub _request_data_sector { shift->_request_sector( 1, @_ ) }
+sub _request_index_sector { shift->_request_sector( 2, @_ ) }
+
+sub _request_sector {
+ my $self = shift;
+ my ($multiple, $size) = @_;
+
+ my $chains_offset = $multiple * $self->byte_size;
+
+ my $old_head = $self->storage->read_at( $self->chains_loc + $chains_offset, $self->byte_size );
+ my $loc = unpack( $StP{$self->byte_size}, $old_head );
+
+ # We don't have any free sectors of the right size, so allocate a new one.
+ unless ( $loc ) {
+ my $offset = $self->storage->request_space( $size );
+
+ # Zero out the new sector. This also guarantees correct increases
+ # in the filesize.
+ $self->storage->print_at( $offset, chr(0) x $size );
+
+ return $offset;
+ }
+
+ # Read the new head after the signature and the staleness counter
+ my $new_head = $self->storage->read_at( $loc + SIG_SIZE + $STALE_SIZE, $self->byte_size );
+ $self->storage->print_at( $self->chains_loc + $chains_offset, $new_head );
+ $self->storage->print_at(
+ $loc + SIG_SIZE + $STALE_SIZE,
+ pack( $StP{$self->byte_size}, 0 ),
+ );
+
+ return $loc;
+}
+
+################################################################################
+
+sub storage { $_[0]{storage} }
+sub byte_size { $_[0]{byte_size} }
+sub hash_size { $_[0]{hash_size} }
+sub hash_chars { $_[0]{hash_chars} }
+sub num_txns { $_[0]{num_txns} }
+sub max_buckets { $_[0]{max_buckets} }
+sub blank_md5 { chr(0) x $_[0]->hash_size }
+sub data_sector_size { $_[0]{data_sector_size} }
+
+# This is a calculated value
+sub txn_bitfield_len {
+ my $self = shift;
+ unless ( exists $self->{txn_bitfield_len} ) {
+ my $temp = ($self->num_txns) / 8;
+ if ( $temp > int( $temp ) ) {
+ $temp = int( $temp ) + 1;
+ }
+ $self->{txn_bitfield_len} = $temp;
+ }
+ return $self->{txn_bitfield_len};
+}
+
+sub trans_id { $_[0]{trans_id} }
+sub set_trans_id { $_[0]{trans_id} = $_[1] }
+
+sub trans_loc { $_[0]{trans_loc} }
+sub set_trans_loc { $_[0]{trans_loc} = $_[1] }
+
+sub chains_loc { $_[0]{chains_loc} }
+sub set_chains_loc { $_[0]{chains_loc} = $_[1] }
+
+################################################################################
+
+package DBM::Deep::10002::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::10002::Engine::Sector::Index' ) ) {
+ return DBM::Deep::10002::Iterator::Index->new({
+ iterator => $self,
+ sector => $sector,
+ });
+ }
+ elsif ( $sector->isa( 'DBM::Deep::10002::Engine::Sector::BucketList' ) ) {
+ return DBM::Deep::10002::Iterator::BucketList->new({
+ iterator => $self,
+ sector => $sector,
+ });
+ }
+
+ DBM::Deep::10002->_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::10002::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::10002::Iterator::BucketList' ) ) {
+ DBM::Deep::10002->_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::10002->_throw_error( "get_next_key(): How did we get here?" );
+}
+
+package DBM::Deep::10002::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::10002::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::10002::Engine::Sector;
+
+sub new {
+ my $self = bless $_[1], $_[0];
+ Scalar::Util::weaken( $self->{engine} );
+ $self->_init;
+ return $self;
+}
+
+#sub _init {}
+#sub clone { DBM::Deep::10002->_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::10002::Engine::Sector::Data;
+
+our @ISA = qw( DBM::Deep::10002::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::10002::Engine::Sector::Scalar;
+
+our @ISA = qw( DBM::Deep::10002::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 $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::10002::Engine::Sector::Null;
+
+our @ISA = qw( DBM::Deep::10002::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::10002::Engine::Sector::Reference;
+
+our @ISA = qw( DBM::Deep::10002::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 - 2 * $e->byte_size;
+
+ my $class_offset = 0;
+ if ( defined $classname ) {
+ my $class_sector = DBM::Deep::10002::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
+ 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 free {
+ my $self = shift;
+
+ 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 staleness { $_[0]{staleness} }
+
+sub get_data_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 $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::10002->_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::10002->_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 ( $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;
+ $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::10002::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::10002->_throw_error( "Cannot read sector at $blist_loc in get_bucket_list()" );
+ my $i = 0;
+ my $last_sector = undef;
+ while ( $sector->isa( 'DBM::Deep::10002::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::10002->_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::10002->_throw_error( "No last_sector when attempting to build a new entry" )
+ unless $last_sector;
+
+ my $blist = DBM::Deep::10002::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( $args->{key_md5} );
+
+ # See whether or not we need to reindex the bucketlist
+ if ( !$sector->has_md5 && $args->{create} && $sector->{idx} == -1 ) {
+ my $new_index = DBM::Deep::10002::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::10002::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 ) );
+ my $blist = $blist_cache{$idx}
+ ||= DBM::Deep::10002::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::10002::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->free;
+
+ $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;
+}
+
+#XXX Add singleton handling here
+sub data {
+ my $self = shift;
+
+ my $new_obj = DBM::Deep::10002->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 $new_obj, $classname;
+ }
+ }
+
+ return $new_obj;
+}
+
+package DBM::Deep::10002::Engine::Sector::BucketList;
+
+our @ISA = qw( DBM::Deep::10002::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 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 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::10002->_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::10002->_throw_error( "write_md5: no key" ) unless exists $args->{key};
+ DBM::Deep::10002->_throw_error( "write_md5: no key_md5" ) unless exists $args->{key_md5};
+ DBM::Deep::10002->_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::10002::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;
+ $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 );
+
+ 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::10002->_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::10002->_throw_error( "get_key_for: No location?" ) unless $location;
+
+ return $self->engine->_load_sector( $location );
+}
+
+package DBM::Deep::10002::Engine::Sector::Index;
+
+our @ISA = qw( DBM::Deep::10002::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 = $self->engine;
+
+ DBM::Deep::10002->_throw_error( "get_entry: Out of range ($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 = $self->engine;
+
+ DBM::Deep::10002->_throw_error( "set_entry: Out of range ($idx)" )
+ if $idx < 0 || $idx >= $e->hash_chars;
+
+ $self->engine->storage->print_at(
+ $self->_loc_for( $idx ),
+ pack( $StP{$e->byte_size}, $loc ),
+ );
+}
+
+1;
+__END__