package DBM::Deep::Engine;
+use 5.6.0;
+
use strict;
+use warnings;
+
+our $VERSION = q(0.99_03);
+
+use Fcntl qw( :DEFAULT :flock );
+use Scalar::Util ();
+
+# File-wide notes:
+# * To add to bucket_size, make sure you modify the following:
+# - calculate_sizes()
+# - _get_key_subloc()
+# - add_bucket() - where the buckets are printed
+#
+# * 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_INTERNAL () { 'i' }
+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_KEYS () { 'K' }
+sub SIG_SIZE () { 1 }
+
+# This is the transaction ID for the HEAD
+sub HEAD () { 0 }
+
+################################################################################
+#
+# This is new code. It is a complete rewrite of the engine based on a new API
+#
+################################################################################
+
+sub read_value {
+ my $self = shift;
+ my ($offset, $key, $orig_key) = @_;
-use Fcntl qw( :DEFAULT :flock :seek );
+ my $dig_key = $self->apply_digest( $key );
+ my $tag = $self->find_blist( $offset, $dig_key ) or return;
+ return $self->get_bucket_value( $tag, $dig_key, $orig_key );
+}
-sub open {
- ##
- # Open a fh to the database, create if nonexistent.
- # Make sure file signature matches DBM::Deep spec.
- ##
+sub key_exists {
my $self = shift;
- my $obj = shift;
-
- if (defined($obj->_fh)) { $self->close( $obj ); }
+ my ($offset, $key) = @_;
- eval {
- local $SIG{'__DIE__'};
- # Theoretically, adding O_BINARY should remove the need for the binmode
- # Of course, testing it is going to be ... interesting.
- my $flags = O_RDWR | O_CREAT | O_BINARY;
+ my $dig_key = $self->apply_digest( $key );
+ # exists() returns the empty string, not undef
+ my $tag = $self->find_blist( $offset, $dig_key ) or return '';
+ return $self->bucket_exists( $tag, $dig_key, $key );
+}
- my $fh;
- sysopen( $fh, $obj->_root->{file}, $flags )
- or $fh = undef;
- $obj->_root->{fh} = $fh;
- }; if ($@ ) { $obj->_throw_error( "Received error: $@\n" ); }
- if (! defined($obj->_fh)) {
- return $obj->_throw_error("Cannot sysopen file: " . $obj->_root->{file} . ": $!");
+sub get_next_key {
+ my $self = shift;
+ my ($offset) = @_;
+
+ # If the previous key was not specifed, start at the top and
+ # return the first one found.
+ my $temp;
+ if ( @_ > 1 ) {
+ $temp = {
+ prev_md5 => $self->apply_digest($_[1]),
+ return_next => 0,
+ };
+ }
+ else {
+ $temp = {
+ prev_md5 => chr(0) x $self->{hash_size},
+ return_next => 1,
+ };
}
- my $fh = $obj->_fh;
+ return $self->traverse_index( $temp, $offset, 0 );
+}
- #XXX Can we remove this by using the right sysopen() flags?
- # Maybe ... q.v. above
- binmode $fh; # for win32
+sub delete_key {
+ my $self = shift;
+ my ($offset, $key, $orig_key) = @_;
- if ($obj->_root->{autoflush}) {
- my $old = select $fh;
- $|=1;
- select $old;
- }
+ my $dig_key = $self->apply_digest( $key );
+ my $tag = $self->find_blist( $offset, $dig_key ) or return;
+ my $value = $self->get_bucket_value( $tag, $dig_key, $orig_key );
+ $self->delete_bucket( $tag, $dig_key, $orig_key );
+ return $value;
+}
- seek($fh, 0 + $obj->_root->{file_offset}, SEEK_SET);
+sub write_value {
+ my $self = shift;
+ my ($offset, $key, $value, $orig_key) = @_;
- my $signature;
- my $bytes_read = read( $fh, $signature, length(DBM::Deep->SIG_FILE));
+ my $dig_key = $self->apply_digest( $key );
+ my $tag = $self->find_blist( $offset, $dig_key, { create => 1 } );
+ return $self->add_bucket( $tag, $dig_key, $key, $value, undef, $orig_key );
+}
- ##
- # File is empty -- write signature and master index
- ##
- if (!$bytes_read) {
- seek($fh, 0 + $obj->_root->{file_offset}, SEEK_SET);
- print( $fh DBM::Deep->SIG_FILE);
- $self->create_tag($obj, $obj->_base_offset, $obj->_type, chr(0) x $DBM::Deep::INDEX_SIZE);
+################################################################################
+#
+# Below here is the old code. It will be folded into the code above as it can.
+#
+################################################################################
+
+sub new {
+ my $class = shift;
+ my ($args) = @_;
+
+ my $self = bless {
+ long_size => 4,
+ long_pack => 'N',
+ data_size => 4,
+ data_pack => 'N',
- my $plain_key = "[base]";
- print( $fh pack($DBM::Deep::DATA_LENGTH_PACK, length($plain_key)) . $plain_key );
+ digest => \&Digest::MD5::md5,
+ hash_size => 16, # In bytes
- # Flush the filehandle
- my $old_fh = select $fh;
- my $old_af = $|; $| = 1; $| = $old_af;
- select $old_fh;
+ ##
+ # Number of buckets per blist before another level of indexing is
+ # done. Increase this value for slightly greater speed, but larger database
+ # files. DO NOT decrease this value below 16, due to risk of recursive
+ # reindex overrun.
+ ##
+ max_buckets => 16,
- my @stats = stat($fh);
- $obj->_root->{inode} = $stats[1];
- $obj->_root->{end} = $stats[7];
+ storage => undef,
+ obj => undef,
+ }, $class;
- return 1;
+ if ( defined $args->{pack_size} ) {
+ if ( lc $args->{pack_size} eq 'small' ) {
+ $args->{long_size} = 2;
+ $args->{long_pack} = 'n';
+ }
+ elsif ( lc $args->{pack_size} eq 'medium' ) {
+ $args->{long_size} = 4;
+ $args->{long_pack} = 'N';
+ }
+ elsif ( lc $args->{pack_size} eq 'large' ) {
+ $args->{long_size} = 8;
+ $args->{long_pack} = 'Q';
+ }
+ else {
+ die "Unknown pack_size value: '$args->{pack_size}'\n";
+ }
}
- ##
- # Check signature was valid
- ##
- unless ($signature eq DBM::Deep->SIG_FILE) {
- $self->close( $obj );
- return $obj->_throw_error("Signature not found -- file is not a Deep DB");
+ # Grab the parameters we want to use
+ foreach my $param ( keys %$self ) {
+ next unless exists $args->{$param};
+ $self->{$param} = $args->{$param};
}
+ Scalar::Util::weaken( $self->{obj} ) if $self->{obj};
- my @stats = stat($fh);
- $obj->_root->{inode} = $stats[1];
- $obj->_root->{end} = $stats[7];
+ if ( $self->{max_buckets} < 16 ) {
+ warn "Floor of max_buckets is 16. Setting it to 16 from '$self->{max_buckets}'\n";
+ $self->{max_buckets} = 16;
+ }
- ##
- # Get our type from master index signature
- ##
- my $tag = $self->load_tag($obj, $obj->_base_offset);
+ return $self;
+}
+
+sub _storage { return $_[0]{storage} }
+
+sub apply_digest {
+ my $self = shift;
+ return $self->{digest}->(@_);
+}
+
+sub calculate_sizes {
+ my $self = shift;
+
+ # The 2**8 here indicates the number of different characters in the
+ # current hashing algorithm
+ #XXX Does this need to be updated with different hashing algorithms?
+ $self->{hash_chars_used} = (2**8);
+ $self->{index_size} = $self->{hash_chars_used} * $self->{long_size};
+
+ $self->{bucket_size} = $self->{hash_size} + $self->{long_size} * 2;
+ $self->{bucket_list_size} = $self->{max_buckets} * $self->{bucket_size};
+
+ $self->{key_size} = $self->{long_size} * 2;
+ $self->{keyloc_size} = $self->{max_buckets} * $self->{key_size};
+
+ return;
+}
-#XXX We probably also want to store the hash algorithm name and not assume anything
-#XXX The cool thing would be to allow a different hashing algorithm at every level
+sub write_file_header {
+ my $self = shift;
+
+ my $loc = $self->_storage->request_space( length( SIG_FILE ) + 33 );
+
+ $self->_storage->print_at( $loc,
+ SIG_FILE,
+ SIG_HEADER,
+ pack('N', 1), # header version
+ pack('N', 24), # header size
+ pack('N4', 0, 0, 0, 0), # currently running transaction IDs
+ pack('n', $self->{long_size}),
+ pack('A', $self->{long_pack}),
+ pack('n', $self->{data_size}),
+ pack('A', $self->{data_pack}),
+ pack('n', $self->{max_buckets}),
+ );
+
+ $self->_storage->set_transaction_offset( 13 );
+
+ return;
+}
- if (!$tag) {
- return $obj->_throw_error("Corrupted file, no master index record");
+sub read_file_header {
+ my $self = shift;
+
+ my $buffer = $self->_storage->read_at( 0, length(SIG_FILE) + 9 );
+ return unless length($buffer);
+
+ my ($file_signature, $sig_header, $header_version, $size) = unpack(
+ 'A4 A N N', $buffer
+ );
+
+ unless ( $file_signature eq SIG_FILE ) {
+ $self->_storage->close;
+ $self->_throw_error( "Signature not found -- file is not a Deep DB" );
}
- if ($obj->{type} ne $tag->{signature}) {
- return $obj->_throw_error("File type mismatch");
+
+ unless ( $sig_header eq SIG_HEADER ) {
+ $self->_storage->close;
+ $self->_throw_error( "Old file version found." );
}
- return 1;
+ my $buffer2 = $self->_storage->read_at( undef, $size );
+ my ($a1, $a2, $a3, $a4, @values) = unpack( 'N4 n A n A n', $buffer2 );
+
+ $self->_storage->set_transaction_offset( 13 );
+
+ if ( @values < 5 || grep { !defined } @values ) {
+ $self->_storage->close;
+ $self->_throw_error("Corrupted file - bad header");
+ }
+
+ #XXX Add warnings if values weren't set right
+ @{$self}{qw(long_size long_pack data_size data_pack max_buckets)} = @values;
+
+ return length($buffer) + length($buffer2);
}
-sub close {
+sub setup_fh {
my $self = shift;
- my $obj = shift;
+ my ($obj) = @_;
- if ( my $fh = $obj->_root->{fh} ) {
- close $fh;
+ # Need to remove use of $fh here
+ my $fh = $self->_storage->{fh};
+ flock $fh, LOCK_EX;
+
+ #XXX The duplication of calculate_sizes needs to go away
+ unless ( $obj->{base_offset} ) {
+ my $bytes_read = $self->read_file_header;
+
+ $self->calculate_sizes;
+
+ ##
+ # File is empty -- write header and master index
+ ##
+ if (!$bytes_read) {
+ $self->_storage->audit( "# Database created on" );
+
+ $self->write_file_header;
+
+ $obj->{base_offset} = $self->_storage->request_space(
+ $self->tag_size( $self->{index_size} ),
+ );
+
+ $self->write_tag(
+ $obj->_base_offset, $obj->_type,
+ chr(0)x$self->{index_size},
+ );
+
+ # Flush the filehandle
+ my $old_fh = select $fh;
+ my $old_af = $|; $| = 1; $| = $old_af;
+ select $old_fh;
+ }
+ else {
+ $obj->{base_offset} = $bytes_read;
+
+ ##
+ # Get our type from master index header
+ ##
+ my $tag = $self->load_tag($obj->_base_offset);
+ unless ( $tag ) {
+ flock $fh, LOCK_UN;
+ $self->_throw_error("Corrupted file, no master index record");
+ }
+
+ unless ($obj->_type eq $tag->{signature}) {
+ flock $fh, LOCK_UN;
+ $self->_throw_error("File type mismatch");
+ }
+ }
+ }
+ else {
+ $self->calculate_sizes;
}
- $obj->_root->{fh} = undef;
+
+ #XXX We have to make sure we don't mess up when autoflush isn't turned on
+ $self->_storage->set_inode;
+
+ flock $fh, LOCK_UN;
return 1;
}
-sub create_tag {
+sub tag_size {
+ my $self = shift;
+ my ($size) = @_;
+ return SIG_SIZE + $self->{data_size} + $size;
+}
+
+sub write_tag {
##
# Given offset, signature and content, create tag and write to disk
##
my $self = shift;
- my ($obj, $offset, $sig, $content) = @_;
- my $size = length($content);
+ my ($offset, $sig, $content) = @_;
+ my $size = length( $content );
- my $fh = $obj->_fh;
+ $self->_storage->print_at(
+ $offset,
+ $sig, pack($self->{data_pack}, $size), $content,
+ );
- seek($fh, $offset + $obj->_root->{file_offset}, SEEK_SET);
- print( $fh $sig . pack($DBM::Deep::DATA_LENGTH_PACK, $size) . $content );
-
- if ($offset == $obj->_root->{end}) {
- $obj->_root->{end} += DBM::Deep->SIG_SIZE + $DBM::Deep::DATA_LENGTH_SIZE + $size;
- }
+ return unless defined $offset;
return {
signature => $sig,
- size => $size,
- offset => $offset + DBM::Deep->SIG_SIZE + $DBM::Deep::DATA_LENGTH_SIZE,
- content => $content
+ #XXX Is this even used?
+ size => $size,
+ offset => $offset + SIG_SIZE + $self->{data_size},
+ content => $content
};
}
# Given offset, load single tag and return signature, size and data
##
my $self = shift;
- my ($obj, $offset) = @_;
-
- my $fh = $obj->_fh;
-
- seek($fh, $offset + $obj->_root->{file_offset}, SEEK_SET);
- if (eof $fh) { return undef; }
+ my ($offset) = @_;
- my $b;
- read( $fh, $b, DBM::Deep->SIG_SIZE + $DBM::Deep::DATA_LENGTH_SIZE );
- my ($sig, $size) = unpack( "A $DBM::Deep::DATA_LENGTH_PACK", $b );
+ my $storage = $self->_storage;
- my $buffer;
- read( $fh, $buffer, $size);
+ my ($sig, $size) = unpack(
+ "A $self->{data_pack}",
+ $storage->read_at( $offset, SIG_SIZE + $self->{data_size} ),
+ );
return {
signature => $sig,
- size => $size,
- offset => $offset + DBM::Deep->SIG_SIZE + $DBM::Deep::DATA_LENGTH_SIZE,
- content => $buffer
+ size => $size, #XXX Is this even used?
+ start => $offset,
+ offset => $offset + SIG_SIZE + $self->{data_size},
+ content => $storage->read_at( undef, $size ),
};
}
-sub index_lookup {
- ##
- # Given index tag, lookup single entry in index and return .
- ##
+sub find_keyloc {
my $self = shift;
- my ($obj, $tag, $index) = @_;
-
- my $location = unpack($DBM::Deep::LONG_PACK, substr($tag->{content}, $index * $DBM::Deep::LONG_SIZE, $DBM::Deep::LONG_SIZE) );
- if (!$location) { return; }
+ my ($tag, $transaction_id) = @_;
+ $transaction_id = $self->_storage->transaction_id
+ unless defined $transaction_id;
+
+ for ( my $i = 0; $i < $self->{max_buckets}; $i++ ) {
+ my ($loc, $trans_id, $is_deleted) = unpack(
+ "$self->{long_pack} C C",
+ substr( $tag->{content}, $i * $self->{key_size}, $self->{key_size} ),
+ );
+
+ next if $loc != HEAD && $transaction_id != $trans_id;
+ return( $loc, $is_deleted, $i * $self->{key_size} );
+ }
- return $self->load_tag( $obj, $location );
+ return;
}
sub add_bucket {
# plain (undigested) key and value.
##
my $self = shift;
- my ($obj, $tag, $md5, $plain_key, $value) = @_;
- my $keys = $tag->{content};
- my $location = 0;
- my $result = 2;
+ my ($tag, $md5, $plain_key, $value, $deleted, $orig_key) = @_;
- my $root = $obj->_root;
+ # This verifies that only supported values will be stored.
+ {
+ my $r = Scalar::Util::reftype( $value );
- my $is_dbm_deep = eval { local $SIG{'__DIE__'}; $value->isa( 'DBM::Deep' ) };
- my $internal_ref = $is_dbm_deep && ($value->_root eq $root);
+ last if !defined $r;
+ last if $r eq 'HASH';
+ last if $r eq 'ARRAY';
- my $fh = $obj->_fh;
+ $self->_throw_error(
+ "Storage of references of type '$r' is not supported."
+ );
+ }
- ##
- # Iterate through buckets, seeing if this is a new entry or a replace.
- ##
- for (my $i=0; $i<$DBM::Deep::MAX_BUCKETS; $i++) {
- my $subloc = unpack($DBM::Deep::LONG_PACK, substr($keys, ($i * $DBM::Deep::BUCKET_SIZE) + $DBM::Deep::HASH_SIZE, $DBM::Deep::LONG_SIZE));
- if (!$subloc) {
- ##
- # Found empty bucket (end of list). Populate and exit loop.
- ##
- $result = 2;
+ my $storage = $self->_storage;
- $location = $internal_ref
- ? $value->_base_offset
- : $root->{end};
+ #ACID - This is a mutation. Must only find the exact transaction
+ my ($keyloc, $offset) = $self->_find_in_buckets( $tag, $md5, 1 );
- seek($fh, $tag->{offset} + ($i * $DBM::Deep::BUCKET_SIZE) + $root->{file_offset}, SEEK_SET);
- print( $fh $md5 . pack($DBM::Deep::LONG_PACK, $location) );
- last;
+ my @transactions;
+ if ( $storage->transaction_id == 0 ) {
+ @transactions = $storage->current_transactions;
+ }
+
+# $self->_release_space( $size, $subloc );
+#XXX This needs updating to use _release_space
+
+ my $location;
+ my $size = $self->_length_needed( $value, $plain_key );
+
+ # Updating a known md5
+ if ( $keyloc ) {
+ my $keytag = $self->load_tag( $keyloc );
+ my ($subloc, $is_deleted, $offset) = $self->find_keyloc( $keytag );
+
+ if ( $subloc && !$is_deleted && @transactions ) {
+ my $old_value = $self->read_from_loc( $subloc, $orig_key );
+ my $old_size = $self->_length_needed( $old_value, $plain_key );
+
+ for my $trans_id ( @transactions ) {
+ my ($loc, $is_deleted, $offset2) = $self->find_keyloc( $keytag, $trans_id );
+ unless ($loc) {
+ my $location2 = $storage->request_space( $old_size );
+ $storage->print_at( $keytag->{offset} + $offset2,
+ pack($self->{long_pack}, $location2 ),
+ pack( 'C C', $trans_id, 0 ),
+ );
+ $self->_write_value( $location2, $plain_key, $old_value, $orig_key );
+ }
+ }
}
- my $key = substr($keys, $i * $DBM::Deep::BUCKET_SIZE, $DBM::Deep::HASH_SIZE);
- if ($md5 eq $key) {
- ##
- # Found existing bucket with same key. Replace with new value.
- ##
- $result = 1;
+ $location = $self->_storage->request_space( $size );
+ #XXX This needs to be transactionally-aware in terms of which keytag->{offset} to use
+ $storage->print_at( $keytag->{offset} + $offset,
+ pack($self->{long_pack}, $location ),
+ pack( 'C C', $storage->transaction_id, 0 ),
+ );
+ }
+ # Adding a new md5
+ else {
+ my $keyloc = $storage->request_space( $self->tag_size( $self->{keyloc_size} ) );
+
+ # The bucket fit into list
+ if ( defined $offset ) {
+ $storage->print_at( $tag->{offset} + $offset,
+ $md5, pack( $self->{long_pack}, $keyloc ),
+ );
+ }
+ # If bucket didn't fit into list, split into a new index level
+ else {
+ $self->split_index( $tag, $md5, $keyloc );
+ }
- if ($internal_ref) {
- $location = $value->_base_offset;
- seek($fh, $tag->{offset} + ($i * $DBM::Deep::BUCKET_SIZE) + $root->{file_offset}, SEEK_SET);
- print( $fh $md5 . pack($DBM::Deep::LONG_PACK, $location) );
- return $result;
- }
+ my $keytag = $self->write_tag(
+ $keyloc, SIG_KEYS, chr(0)x$self->{keyloc_size},
+ );
+
+ $location = $self->_storage->request_space( $size );
+ $storage->print_at( $keytag->{offset},
+ pack( $self->{long_pack}, $location ),
+ pack( 'C C', $storage->transaction_id, 0 ),
+ );
+
+ my $offset = 1;
+ for my $trans_id ( @transactions ) {
+ $storage->print_at( $keytag->{offset} + $self->{key_size} * $offset++,
+ pack( $self->{long_pack}, 0 ),
+ pack( 'C C', $trans_id, 1 ),
+ );
+ }
+ }
- seek($fh, $subloc + DBM::Deep->SIG_SIZE + $root->{file_offset}, SEEK_SET);
- my $size;
- read( $fh, $size, $DBM::Deep::DATA_LENGTH_SIZE); $size = unpack($DBM::Deep::DATA_LENGTH_PACK, $size);
+ $self->_write_value( $location, $plain_key, $value, $orig_key );
- ##
- # If value is a hash, array, or raw value with equal or less size, we can
- # reuse the same content area of the database. Otherwise, we have to create
- # a new content area at the EOF.
- ##
- my $actual_length;
- my $r = Scalar::Util::reftype( $value ) || '';
- if ( $r eq 'HASH' || $r eq 'ARRAY' ) {
- $actual_length = $DBM::Deep::INDEX_SIZE;
-
- # if autobless is enabled, must also take into consideration
- # the class name, as it is stored along with key/value.
- if ( $root->{autobless} ) {
- my $value_class = Scalar::Util::blessed($value);
- if ( defined $value_class && !$value->isa('DBM::Deep') ) {
- $actual_length += length($value_class);
- }
- }
- }
- else { $actual_length = length($value); }
+ return 1;
+}
- if ($actual_length <= $size) {
- $location = $subloc;
- }
- else {
- $location = $root->{end};
- seek($fh, $tag->{offset} + ($i * $DBM::Deep::BUCKET_SIZE) + $DBM::Deep::HASH_SIZE + $root->{file_offset}, SEEK_SET);
- print( $fh pack($DBM::Deep::LONG_PACK, $location) );
- }
+sub _write_value {
+ my $self = shift;
+ my ($location, $key, $value, $orig_key) = @_;
- last;
+ my $storage = $self->_storage;
+
+ my $dbm_deep_obj = _get_dbm_object( $value );
+ if ( $dbm_deep_obj && $dbm_deep_obj->_storage ne $storage ) {
+ $self->_throw_error( "Cannot cross-reference. Use export() instead" );
+ }
+
+ ##
+ # Write signature based on content type, set content length and write
+ # actual value.
+ ##
+ my $r = Scalar::Util::reftype( $value ) || '';
+ if ( $dbm_deep_obj ) {
+ $self->write_tag( $location, SIG_INTERNAL,pack($self->{long_pack}, $dbm_deep_obj->_base_offset) );
+ }
+ elsif ($r eq 'HASH') {
+ if ( !$dbm_deep_obj && tied %{$value} ) {
+ $self->_throw_error( "Cannot store something that is tied" );
+ }
+ $self->write_tag( $location, SIG_HASH, chr(0)x$self->{index_size} );
+ }
+ elsif ($r eq 'ARRAY') {
+ if ( !$dbm_deep_obj && tied @{$value} ) {
+ $self->_throw_error( "Cannot store something that is tied" );
}
+ $self->write_tag( $location, SIG_ARRAY, chr(0)x$self->{index_size} );
+ }
+ elsif (!defined($value)) {
+ $self->write_tag( $location, SIG_NULL, '' );
+ }
+ else {
+ $self->write_tag( $location, SIG_DATA, $value );
}
##
- # If this is an internal reference, return now.
- # No need to write value or plain key
+ # Plain key is stored AFTER value, as keys are typically fetched less often.
##
- if ($internal_ref) {
- return $result;
+ $storage->print_at( undef, pack($self->{data_pack}, length($key)) . $key );
+
+ # Internal references don't care about autobless
+ return 1 if $dbm_deep_obj;
+
+ ##
+ # If value is blessed, preserve class name
+ ##
+ if ( $storage->{autobless} ) {
+ if ( defined( my $c = Scalar::Util::blessed($value) ) ) {
+ $storage->print_at( undef, chr(1), pack($self->{data_pack}, length($c)) . $c );
+ }
+ else {
+ $storage->print_at( undef, chr(0) );
+ }
}
##
- # If bucket didn't fit into list, split into a new index level
+ # Tie the passed in reference so that changes to it are reflected in the
+ # datafile. The use of $location as the base_offset will act as the
+ # the linkage between parent and child.
+ #
+ # The overall assignment is a hack around the fact that just tying doesn't
+ # store the values. This may not be the wrong thing to do.
##
- if (!$location) {
- seek($fh, $tag->{ref_loc} + $root->{file_offset}, SEEK_SET);
- print( $fh pack($DBM::Deep::LONG_PACK, $root->{end}) );
+ if ($r eq 'HASH') {
+ my %x = %$value;
+ tie %$value, 'DBM::Deep', {
+ base_offset => $location,
+ storage => $storage,
+ parent => $self->{obj},
+ parent_key => $orig_key,
+ };
+ %$value = %x;
+ bless $value, 'DBM::Deep::Hash' unless Scalar::Util::blessed( $value );
+ }
+ elsif ($r eq 'ARRAY') {
+ my @x = @$value;
+ tie @$value, 'DBM::Deep', {
+ base_offset => $location,
+ storage => $storage,
+ parent => $self->{obj},
+ parent_key => $orig_key,
+ };
+ @$value = @x;
+ bless $value, 'DBM::Deep::Array' unless Scalar::Util::blessed( $value );
+ }
- my $index_tag = $self->create_tag($obj, $root->{end}, DBM::Deep->SIG_INDEX, chr(0) x $DBM::Deep::INDEX_SIZE);
- my @offsets = ();
+ return 1;
+}
- $keys .= $md5 . pack($DBM::Deep::LONG_PACK, 0);
+sub split_index {
+ my $self = shift;
+ my ($tag, $md5, $keyloc) = @_;
- for (my $i=0; $i<=$DBM::Deep::MAX_BUCKETS; $i++) {
- my $key = substr($keys, $i * $DBM::Deep::BUCKET_SIZE, $DBM::Deep::HASH_SIZE);
- if ($key) {
- my $old_subloc = unpack($DBM::Deep::LONG_PACK, substr($keys, ($i * $DBM::Deep::BUCKET_SIZE) +
- $DBM::Deep::HASH_SIZE, $DBM::Deep::LONG_SIZE));
- my $num = ord(substr($key, $tag->{ch} + 1, 1));
+ my $storage = $self->_storage;
- if ($offsets[$num]) {
- my $offset = $offsets[$num] + DBM::Deep->SIG_SIZE + $DBM::Deep::DATA_LENGTH_SIZE;
- seek($fh, $offset + $root->{file_offset}, SEEK_SET);
- my $subkeys;
- read( $fh, $subkeys, $DBM::Deep::BUCKET_LIST_SIZE);
+ my $loc = $storage->request_space(
+ $self->tag_size( $self->{index_size} ),
+ );
- for (my $k=0; $k<$DBM::Deep::MAX_BUCKETS; $k++) {
- my $subloc = unpack($DBM::Deep::LONG_PACK, substr($subkeys, ($k * $DBM::Deep::BUCKET_SIZE) +
- $DBM::Deep::HASH_SIZE, $DBM::Deep::LONG_SIZE));
- if (!$subloc) {
- seek($fh, $offset + ($k * $DBM::Deep::BUCKET_SIZE) + $root->{file_offset}, SEEK_SET);
- print( $fh $key . pack($DBM::Deep::LONG_PACK, $old_subloc || $root->{end}) );
- last;
- }
- } # k loop
- }
- else {
- $offsets[$num] = $root->{end};
- seek($fh, $index_tag->{offset} + ($num * $DBM::Deep::LONG_SIZE) + $root->{file_offset}, SEEK_SET);
- print( $fh pack($DBM::Deep::LONG_PACK, $root->{end}) );
+ $storage->print_at( $tag->{ref_loc}, pack($self->{long_pack}, $loc) );
- my $blist_tag = $self->create_tag($obj, $root->{end}, DBM::Deep->SIG_BLIST, chr(0) x $DBM::Deep::BUCKET_LIST_SIZE);
+ my $index_tag = $self->write_tag(
+ $loc, SIG_INDEX,
+ chr(0)x$self->{index_size},
+ );
- seek($fh, $blist_tag->{offset} + $root->{file_offset}, SEEK_SET);
- print( $fh $key . pack($DBM::Deep::LONG_PACK, $old_subloc || $root->{end}) );
- }
- } # key is real
- } # i loop
+ my $keys = $tag->{content}
+ . $md5 . pack($self->{long_pack}, $keyloc);
+
+ my @newloc = ();
+ BUCKET:
+ # The <= here is deliberate - we have max_buckets+1 keys to iterate
+ # through, unlike every other loop that uses max_buckets as a stop.
+ for (my $i = 0; $i <= $self->{max_buckets}; $i++) {
+ my ($key, $old_subloc) = $self->_get_key_subloc( $keys, $i );
+
+ die "[INTERNAL ERROR]: No key in split_index()\n" unless $key;
+ die "[INTERNAL ERROR]: No subloc in split_index()\n" unless $old_subloc;
+
+ my $num = ord(substr($key, $tag->{ch} + 1, 1));
+
+ if ($newloc[$num]) {
+ my $subkeys = $storage->read_at( $newloc[$num], $self->{bucket_list_size} );
+
+ # This is looking for the first empty spot
+ my ($subloc, $offset) = $self->_find_in_buckets(
+ { content => $subkeys }, '',
+ );
+
+ $storage->print_at(
+ $newloc[$num] + $offset,
+ $key, pack($self->{long_pack}, $old_subloc),
+ );
+
+ next;
+ }
+
+ my $loc = $storage->request_space(
+ $self->tag_size( $self->{bucket_list_size} ),
+ );
+
+ $storage->print_at(
+ $index_tag->{offset} + ($num * $self->{long_size}),
+ pack($self->{long_pack}, $loc),
+ );
+
+ my $blist_tag = $self->write_tag(
+ $loc, SIG_BLIST,
+ chr(0)x$self->{bucket_list_size},
+ );
+
+ $storage->print_at( $blist_tag->{offset}, $key . pack($self->{long_pack}, $old_subloc) );
+
+ $newloc[$num] = $blist_tag->{offset};
+ }
+
+ $self->_release_space(
+ $self->tag_size( $self->{bucket_list_size} ),
+ $tag->{start},
+ );
+
+ return 1;
+}
+
+sub read_from_loc {
+ my $self = shift;
+ my ($subloc, $orig_key) = @_;
+
+ my $storage = $self->_storage;
- $location ||= $root->{end};
- } # re-index bucket list
+ my $signature = $storage->read_at( $subloc, SIG_SIZE );
##
- # Seek to content area and store signature, value and plaintext key
+ # If value is a hash or array, return new DBM::Deep object with correct offset
##
- if ($location) {
- my $content_length;
- seek($fh, $location + $root->{file_offset}, SEEK_SET);
+ if (($signature eq SIG_HASH) || ($signature eq SIG_ARRAY)) {
+ #XXX This needs to be a singleton
+# my $new_obj;
+# my $is_autobless;
+# if ( $signature eq SIG_HASH ) {
+# $new_obj = {};
+# tie %$new_obj, 'DBM::Deep', {
+# base_offset => $subloc,
+# storage => $self->_storage,
+# parent => $self->{obj},
+# parent_key => $orig_key,
+# };
+# $is_autobless = tied(%$new_obj)->_storage->{autobless};
+# }
+# else {
+# $new_obj = [];
+# tie @$new_obj, 'DBM::Deep', {
+# base_offset => $subloc,
+# storage => $self->_storage,
+# parent => $self->{obj},
+# parent_key => $orig_key,
+# };
+# $is_autobless = tied(@$new_obj)->_storage->{autobless};
+# }
+#
+# if ($is_autobless) {
+
+ my $new_obj = DBM::Deep->new({
+ type => $signature,
+ base_offset => $subloc,
+ storage => $self->_storage,
+ parent => $self->{obj},
+ parent_key => $orig_key,
+ });
+
+ if ($new_obj->_storage->{autobless}) {
+ ##
+ # Skip over value and plain key to see if object needs
+ # to be re-blessed
+ ##
+ $storage->increment_pointer( $self->{data_size} + $self->{index_size} );
- ##
- # Write signature based on content type, set content length and write actual value.
- ##
- my $r = Scalar::Util::reftype($value) || '';
- if ($r eq 'HASH') {
- print( $fh DBM::Deep->TYPE_HASH );
- print( $fh pack($DBM::Deep::DATA_LENGTH_PACK, $DBM::Deep::INDEX_SIZE) . chr(0) x $DBM::Deep::INDEX_SIZE );
- $content_length = $DBM::Deep::INDEX_SIZE;
- }
- elsif ($r eq 'ARRAY') {
- print( $fh DBM::Deep->TYPE_ARRAY );
- print( $fh pack($DBM::Deep::DATA_LENGTH_PACK, $DBM::Deep::INDEX_SIZE) . chr(0) x $DBM::Deep::INDEX_SIZE );
- $content_length = $DBM::Deep::INDEX_SIZE;
+ my $size = $storage->read_at( undef, $self->{data_size} );
+ $size = unpack($self->{data_pack}, $size);
+ if ($size) { $storage->increment_pointer( $size ); }
+
+ my $bless_bit = $storage->read_at( undef, 1 );
+ if ( ord($bless_bit) ) {
+ my $size = unpack(
+ $self->{data_pack},
+ $storage->read_at( undef, $self->{data_size} ),
+ );
+
+ if ( $size ) {
+ $new_obj = bless $new_obj, $storage->read_at( undef, $size );
+ }
+ }
}
- elsif (!defined($value)) {
- print( $fh DBM::Deep->SIG_NULL );
- print( $fh pack($DBM::Deep::DATA_LENGTH_PACK, 0) );
- $content_length = 0;
+
+ return $new_obj;
+ }
+ elsif ( $signature eq SIG_INTERNAL ) {
+ my $size = $storage->read_at( undef, $self->{data_size} );
+ $size = unpack($self->{data_pack}, $size);
+
+ if ( $size ) {
+ my $new_loc = $storage->read_at( undef, $size );
+ $new_loc = unpack( $self->{long_pack}, $new_loc );
+ return $self->read_from_loc( $new_loc, $orig_key );
}
else {
- print( $fh DBM::Deep->SIG_DATA );
- print( $fh pack($DBM::Deep::DATA_LENGTH_PACK, length($value)) . $value );
- $content_length = length($value);
+ return;
}
+ }
+ ##
+ # Otherwise return actual value
+ ##
+ elsif ( $signature eq SIG_DATA ) {
+ my $size = $storage->read_at( undef, $self->{data_size} );
+ $size = unpack($self->{data_pack}, $size);
- ##
- # Plain key is stored AFTER value, as keys are typically fetched less often.
- ##
- print( $fh pack($DBM::Deep::DATA_LENGTH_PACK, length($plain_key)) . $plain_key );
+ my $value = $size ? $storage->read_at( undef, $size ) : '';
+ return $value;
+ }
- ##
- # If value is blessed, preserve class name
- ##
- if ( $root->{autobless} ) {
- my $value_class = Scalar::Util::blessed($value);
- if ( defined $value_class && $value_class ne 'DBM::Deep' ) {
- ##
- # Blessed ref -- will restore later
- ##
- print( $fh chr(1) );
- print( $fh pack($DBM::Deep::DATA_LENGTH_PACK, length($value_class)) . $value_class );
- $content_length += 1;
- $content_length += $DBM::Deep::DATA_LENGTH_SIZE + length($value_class);
- }
- else {
- print( $fh chr(0) );
- $content_length += 1;
- }
- }
+ ##
+ # Key exists, but content is null
+ ##
+ return;
+}
- ##
- # If this is a new content area, advance EOF counter
- ##
- if ($location == $root->{end}) {
- $root->{end} += DBM::Deep->SIG_SIZE;
- $root->{end} += $DBM::Deep::DATA_LENGTH_SIZE + $content_length;
- $root->{end} += $DBM::Deep::DATA_LENGTH_SIZE + length($plain_key);
+sub get_bucket_value {
+ ##
+ # Fetch single value given tag and MD5 digested key.
+ ##
+ my $self = shift;
+ my ($tag, $md5, $orig_key) = @_;
+
+ #ACID - This is a read. Can find exact or HEAD
+ my ($keyloc, $offset) = $self->_find_in_buckets( $tag, $md5 );
+
+ if ( !$keyloc ) {
+ #XXX Need to use real key
+# $self->add_bucket( $tag, $md5, $orig_key, undef, $orig_key );
+# return;
+ }
+# elsif ( !$is_deleted ) {
+ else {
+ my $keytag = $self->load_tag( $keyloc );
+ my ($subloc, $is_deleted) = $self->find_keyloc( $keytag );
+ if (!$subloc && !$is_deleted) {
+ ($subloc, $is_deleted) = $self->find_keyloc( $keytag, 0 );
}
+ if ( $subloc && !$is_deleted ) {
+ return $self->read_from_loc( $subloc, $orig_key );
+ }
+ }
- ##
- # If content is a hash or array, create new child DBM::Deep object and
- # pass each key or element to it.
- ##
- if ($r eq 'HASH') {
- my $branch = DBM::Deep->new(
- type => DBM::Deep->TYPE_HASH,
- base_offset => $location,
- root => $root,
- );
- foreach my $key (keys %{$value}) {
- $branch->STORE( $key, $value->{$key} );
+ return;
+}
+
+sub delete_bucket {
+ ##
+ # Delete single key/value pair given tag and MD5 digested key.
+ ##
+ my $self = shift;
+ my ($tag, $md5, $orig_key) = @_;
+
+ #ACID - Although this is a mutation, we must find any transaction.
+ # This is because we need to mark something as deleted that is in the HEAD.
+ my ($keyloc, $offset) = $self->_find_in_buckets( $tag, $md5 );
+
+ return if !$keyloc;
+
+ my $storage = $self->_storage;
+
+ my @transactions;
+ if ( $storage->transaction_id == 0 ) {
+ @transactions = $storage->current_transactions;
+ }
+
+ if ( $storage->transaction_id == 0 ) {
+ my $keytag = $self->load_tag( $keyloc );
+
+ my ($subloc, $is_deleted, $offset) = $self->find_keyloc( $keytag );
+ return if !$subloc || $is_deleted;
+
+ my $value = $self->read_from_loc( $subloc, $orig_key );
+
+ my $size = $self->_length_needed( $value, $orig_key );
+
+ for my $trans_id ( @transactions ) {
+ my ($loc, $is_deleted, $offset2) = $self->find_keyloc( $keytag, $trans_id );
+ unless ($loc) {
+ my $location2 = $storage->request_space( $size );
+ $storage->print_at( $keytag->{offset} + $offset2,
+ pack($self->{long_pack}, $location2 ),
+ pack( 'C C', $trans_id, 0 ),
+ );
+ $self->_write_value( $location2, $orig_key, $value, $orig_key );
}
}
- elsif ($r eq 'ARRAY') {
- my $branch = DBM::Deep->new(
- type => DBM::Deep->TYPE_ARRAY,
- base_offset => $location,
- root => $root,
+
+ $keytag = $self->load_tag( $keyloc );
+ ($subloc, $is_deleted, $offset) = $self->find_keyloc( $keytag );
+ $storage->print_at( $keytag->{offset} + $offset,
+ substr( $keytag->{content}, $offset + $self->{key_size} ),
+ chr(0) x $self->{key_size},
+ );
+ }
+ else {
+ my $keytag = $self->load_tag( $keyloc );
+
+ my ($subloc, $is_deleted, $offset) = $self->find_keyloc( $keytag );
+
+ $storage->print_at( $keytag->{offset} + $offset,
+ pack($self->{long_pack}, 0 ),
+ pack( 'C C', $storage->transaction_id, 1 ),
+ );
+ }
+
+ return 1;
+}
+
+sub bucket_exists {
+ ##
+ # Check existence of single key given tag and MD5 digested key.
+ ##
+ my $self = shift;
+ my ($tag, $md5) = @_;
+
+ #ACID - This is a read. Can find exact or HEAD
+ my ($keyloc) = $self->_find_in_buckets( $tag, $md5 );
+ my $keytag = $self->load_tag( $keyloc );
+ my ($subloc, $is_deleted, $offset) = $self->find_keyloc( $keytag );
+ if ( !$subloc && !$is_deleted ) {
+ ($subloc, $is_deleted, $offset) = $self->find_keyloc( $keytag, 0 );
+ }
+ return ($subloc && !$is_deleted) && 1;
+}
+
+sub find_blist {
+ ##
+ # Locate offset for bucket list, given digested key
+ ##
+ my $self = shift;
+ my ($offset, $md5, $args) = @_;
+ $args = {} unless $args;
+
+ ##
+ # Locate offset for bucket list using digest index system
+ ##
+ my $tag = $self->load_tag( $offset )
+ or $self->_throw_error( "INTERNAL ERROR - Cannot find tag" );
+
+ #XXX What happens when $ch >= $self->{hash_size} ??
+ for (my $ch = 0; $tag->{signature} ne SIG_BLIST; $ch++) {
+ my $num = ord substr($md5, $ch, 1);
+
+ my $ref_loc = $tag->{offset} + ($num * $self->{long_size});
+ $tag = $self->index_lookup( $tag, $num );
+
+ if (!$tag) {
+ return if !$args->{create};
+
+ my $loc = $self->_storage->request_space(
+ $self->tag_size( $self->{bucket_list_size} ),
);
- my $index = 0;
- foreach my $element (@{$value}) {
- $branch->STORE( $index, $element );
- $index++;
- }
+
+ $self->_storage->print_at( $ref_loc, pack($self->{long_pack}, $loc) );
+
+ $tag = $self->write_tag(
+ $loc, SIG_BLIST,
+ chr(0)x$self->{bucket_list_size},
+ );
+
+ $tag->{ref_loc} = $ref_loc;
+ $tag->{ch} = $ch;
+
+ last;
}
- return $result;
+ $tag->{ch} = $ch;
+ $tag->{ref_loc} = $ref_loc;
}
- return $obj->_throw_error("Fatal error: indexing failed -- possibly due to corruption in file");
+ return $tag;
}
-sub get_bucket_value {
- ##
- # Fetch single value given tag and MD5 digested key.
- ##
- my $self = shift;
- my ($obj, $tag, $md5) = @_;
- my $keys = $tag->{content};
-
- my $fh = $obj->_fh;
-
- ##
- # Iterate through buckets, looking for a key match
- ##
- BUCKET:
- for (my $i=0; $i<$DBM::Deep::MAX_BUCKETS; $i++) {
- my $key = substr($keys, $i * $DBM::Deep::BUCKET_SIZE, $DBM::Deep::HASH_SIZE);
- my $subloc = unpack($DBM::Deep::LONG_PACK, substr($keys, ($i * $DBM::Deep::BUCKET_SIZE) + $DBM::Deep::HASH_SIZE, $DBM::Deep::LONG_SIZE));
-
- if (!$subloc) {
- ##
- # Hit end of list, no match
- ##
- return;
- }
-
- if ( $md5 ne $key ) {
- next BUCKET;
- }
+sub index_lookup {
+ ##
+ # Given index tag, lookup single entry in index and return .
+ ##
+ my $self = shift;
+ my ($tag, $index) = @_;
- ##
- # Found match -- seek to offset and read signature
- ##
- my $signature;
- seek($fh, $subloc + $obj->_root->{file_offset}, SEEK_SET);
- read( $fh, $signature, DBM::Deep->SIG_SIZE);
-
- ##
- # If value is a hash or array, return new DBM::Deep object with correct offset
- ##
- if (($signature eq DBM::Deep->TYPE_HASH) || ($signature eq DBM::Deep->TYPE_ARRAY)) {
- my $obj = DBM::Deep->new(
- type => $signature,
- base_offset => $subloc,
- root => $obj->_root,
+ my $location = unpack(
+ $self->{long_pack},
+ substr(
+ $tag->{content},
+ $index * $self->{long_size},
+ $self->{long_size},
+ ),
+ );
+
+ if (!$location) { return; }
+
+ return $self->load_tag( $location );
+}
+
+sub traverse_index {
+ ##
+ # Scan index and recursively step into deeper levels, looking for next key.
+ ##
+ my $self = shift;
+ my ($xxxx, $offset, $ch, $force_return_next) = @_;
+
+ my $tag = $self->load_tag( $offset );
+
+ if ($tag->{signature} ne SIG_BLIST) {
+ my $start = $xxxx->{return_next} ? 0 : ord(substr($xxxx->{prev_md5}, $ch, 1));
+
+ for (my $idx = $start; $idx < $self->{hash_chars_used}; $idx++) {
+ my $subloc = unpack(
+ $self->{long_pack},
+ substr(
+ $tag->{content},
+ $idx * $self->{long_size},
+ $self->{long_size},
+ ),
);
-
- if ($obj->_root->{autobless}) {
- ##
- # Skip over value and plain key to see if object needs
- # to be re-blessed
- ##
- seek($fh, $DBM::Deep::DATA_LENGTH_SIZE + $DBM::Deep::INDEX_SIZE, SEEK_CUR);
-
- my $size;
- read( $fh, $size, $DBM::Deep::DATA_LENGTH_SIZE); $size = unpack($DBM::Deep::DATA_LENGTH_PACK, $size);
- if ($size) { seek($fh, $size, SEEK_CUR); }
-
- my $bless_bit;
- read( $fh, $bless_bit, 1);
- if (ord($bless_bit)) {
- ##
- # Yes, object needs to be re-blessed
- ##
- my $class_name;
- read( $fh, $size, $DBM::Deep::DATA_LENGTH_SIZE); $size = unpack($DBM::Deep::DATA_LENGTH_PACK, $size);
- if ($size) { read( $fh, $class_name, $size); }
- if ($class_name) { $obj = bless( $obj, $class_name ); }
- }
+
+ if ($subloc) {
+ my $result = $self->traverse_index(
+ $xxxx, $subloc, $ch + 1, $force_return_next,
+ );
+
+ if (defined $result) { return $result; }
}
-
- return $obj;
- }
-
+ } # index loop
+
+ $xxxx->{return_next} = 1;
+ }
+ # This is the bucket list
+ else {
+ my $keys = $tag->{content};
+ if ($force_return_next) { $xxxx->{return_next} = 1; }
+
##
- # Otherwise return actual value
+ # Iterate through buckets, looking for a key match
##
- elsif ($signature eq DBM::Deep->SIG_DATA) {
- my $size;
- my $value = '';
- read( $fh, $size, $DBM::Deep::DATA_LENGTH_SIZE); $size = unpack($DBM::Deep::DATA_LENGTH_PACK, $size);
- if ($size) { read( $fh, $value, $size); }
- return $value;
+ my $transaction_id = $self->_storage->transaction_id;
+ for (my $i = 0; $i < $self->{max_buckets}; $i++) {
+ my ($key, $keyloc) = $self->_get_key_subloc( $keys, $i );
+
+ # End of bucket list -- return to outer loop
+ if (!$keyloc) {
+ $xxxx->{return_next} = 1;
+ last;
+ }
+ # Located previous key -- return next one found
+ elsif ($key eq $xxxx->{prev_md5}) {
+ $xxxx->{return_next} = 1;
+ next;
+ }
+ # Seek to bucket location and skip over signature
+ elsif ($xxxx->{return_next}) {
+ my $storage = $self->_storage;
+
+ my $keytag = $self->load_tag( $keyloc );
+ my ($subloc, $is_deleted) = $self->find_keyloc( $keytag );
+ if ( $subloc == 0 && !$is_deleted ) {
+ ($subloc, $is_deleted) = $self->find_keyloc( $keytag, 0 );
+ }
+ next if $is_deleted;
+
+ # Skip over value to get to plain key
+ my $sig = $storage->read_at( $subloc, SIG_SIZE );
+
+ my $size = $storage->read_at( undef, $self->{data_size} );
+ $size = unpack($self->{data_pack}, $size);
+ if ($size) { $storage->increment_pointer( $size ); }
+
+ # Read in plain key and return as scalar
+ $size = $storage->read_at( undef, $self->{data_size} );
+ $size = unpack($self->{data_pack}, $size);
+
+ my $plain_key;
+ if ($size) { $plain_key = $storage->read_at( undef, $size); }
+ return $plain_key;
+ }
}
-
- ##
- # Key exists, but content is null
- ##
- else { return; }
- } # i loop
- return;
+ $xxxx->{return_next} = 1;
+ }
+
+ return;
}
-sub delete_bucket {
- ##
- # Delete single key/value pair given tag and MD5 digested key.
- ##
- my $self = shift;
- my ($obj, $tag, $md5) = @_;
- my $keys = $tag->{content};
-
- my $fh = $obj->_fh;
-
- ##
- # Iterate through buckets, looking for a key match
- ##
- BUCKET:
- for (my $i=0; $i<$DBM::Deep::MAX_BUCKETS; $i++) {
- my $key = substr($keys, $i * $DBM::Deep::BUCKET_SIZE, $DBM::Deep::HASH_SIZE);
- my $subloc = unpack($DBM::Deep::LONG_PACK, substr($keys, ($i * $DBM::Deep::BUCKET_SIZE) + $DBM::Deep::HASH_SIZE, $DBM::Deep::LONG_SIZE));
-
- if (!$subloc) {
- ##
- # Hit end of list, no match
- ##
- return;
- }
-
- if ( $md5 ne $key ) {
- next BUCKET;
- }
+# Utilities
- ##
- # Matched key -- delete bucket and return
- ##
- seek($fh, $tag->{offset} + ($i * $DBM::Deep::BUCKET_SIZE) + $obj->_root->{file_offset}, SEEK_SET);
- print( $fh substr($keys, ($i+1) * $DBM::Deep::BUCKET_SIZE ) );
- print( $fh chr(0) x $DBM::Deep::BUCKET_SIZE );
-
- return 1;
- } # i loop
-
- return;
+sub _get_key_subloc {
+ my $self = shift;
+ my ($keys, $idx) = @_;
+
+ return unpack(
+ # This is 'a', not 'A'. Please read the pack() documentation for the
+ # difference between the two and why it's important.
+ "a$self->{hash_size} $self->{long_pack}",
+ substr(
+ $keys,
+ ($idx * $self->{bucket_size}),
+ $self->{bucket_size},
+ ),
+ );
}
-sub bucket_exists {
- ##
- # Check existence of single key given tag and MD5 digested key.
- ##
- my $self = shift;
- my ($obj, $tag, $md5) = @_;
- my $keys = $tag->{content};
-
- ##
- # Iterate through buckets, looking for a key match
- ##
+sub _find_in_buckets {
+ my $self = shift;
+ my ($tag, $md5) = @_;
+
BUCKET:
- for (my $i=0; $i<$DBM::Deep::MAX_BUCKETS; $i++) {
- my $key = substr($keys, $i * $DBM::Deep::BUCKET_SIZE, $DBM::Deep::HASH_SIZE);
- my $subloc = unpack($DBM::Deep::LONG_PACK, substr($keys, ($i * $DBM::Deep::BUCKET_SIZE) + $DBM::Deep::HASH_SIZE, $DBM::Deep::LONG_SIZE));
-
- if (!$subloc) {
- ##
- # Hit end of list, no match
- ##
- return;
- }
-
- if ( $md5 ne $key ) {
- next BUCKET;
- }
+ for ( my $i = 0; $i < $self->{max_buckets}; $i++ ) {
+ my ($key, $subloc) = $self->_get_key_subloc(
+ $tag->{content}, $i,
+ );
- ##
- # Matched key -- return true
- ##
- return 1;
- } # i loop
+ next BUCKET if $subloc && $key ne $md5;
+ return( $subloc, $i * $self->{bucket_size} );
+ }
- return;
+ return;
}
-sub find_bucket_list {
- ##
- # Locate offset for bucket list, given digested key
- ##
- my $self = shift;
- my ($obj, $md5) = @_;
-
- ##
- # Locate offset for bucket list using digest index system
- ##
- my $ch = 0;
- my $tag = $self->load_tag($obj, $obj->_base_offset);
- if (!$tag) { return; }
-
- while ($tag->{signature} ne DBM::Deep->SIG_BLIST) {
- $tag = $self->index_lookup($obj, $tag, ord(substr($md5, $ch, 1)));
- if (!$tag) { return; }
- $ch++;
- }
-
- return $tag;
+sub _release_space {
+ my $self = shift;
+ my ($size, $loc) = @_;
+
+ my $next_loc = 0;
+
+ $self->_storage->print_at( $loc,
+ SIG_FREE,
+ pack($self->{long_pack}, $size ),
+ pack($self->{long_pack}, $next_loc ),
+ );
+
+ return;
}
-sub traverse_index {
- ##
- # Scan index and recursively step into deeper levels, looking for next key.
- ##
- my $self = shift;
- my ($obj, $offset, $ch, $force_return_next) = @_;
- $force_return_next = undef unless $force_return_next;
-
- my $tag = $self->load_tag($obj, $offset );
-
- my $fh = $obj->_fh;
-
- if ($tag->{signature} ne DBM::Deep->SIG_BLIST) {
- my $content = $tag->{content};
- my $start;
- if ($obj->{return_next}) { $start = 0; }
- else { $start = ord(substr($obj->{prev_md5}, $ch, 1)); }
-
- for (my $index = $start; $index < 256; $index++) {
- my $subloc = unpack($DBM::Deep::LONG_PACK, substr($content, $index * $DBM::Deep::LONG_SIZE, $DBM::Deep::LONG_SIZE) );
- if ($subloc) {
- my $result = $self->traverse_index( $obj, $subloc, $ch + 1, $force_return_next );
- if (defined($result)) { return $result; }
- }
- } # index loop
-
- $obj->{return_next} = 1;
- } # tag is an index
-
- elsif ($tag->{signature} eq DBM::Deep->SIG_BLIST) {
- my $keys = $tag->{content};
- if ($force_return_next) { $obj->{return_next} = 1; }
-
- ##
- # Iterate through buckets, looking for a key match
- ##
- for (my $i=0; $i<$DBM::Deep::MAX_BUCKETS; $i++) {
- my $key = substr($keys, $i * $DBM::Deep::BUCKET_SIZE, $DBM::Deep::HASH_SIZE);
- my $subloc = unpack($DBM::Deep::LONG_PACK, substr($keys, ($i * $DBM::Deep::BUCKET_SIZE) + $DBM::Deep::HASH_SIZE, $DBM::Deep::LONG_SIZE));
-
- if (!$subloc) {
- ##
- # End of bucket list -- return to outer loop
- ##
- $obj->{return_next} = 1;
- last;
- }
- elsif ($key eq $obj->{prev_md5}) {
- ##
- # Located previous key -- return next one found
- ##
- $obj->{return_next} = 1;
- next;
- }
- elsif ($obj->{return_next}) {
- ##
- # Seek to bucket location and skip over signature
- ##
- seek($fh, $subloc + DBM::Deep->SIG_SIZE + $obj->_root->{file_offset}, SEEK_SET);
-
- ##
- # Skip over value to get to plain key
- ##
- my $size;
- read( $fh, $size, $DBM::Deep::DATA_LENGTH_SIZE); $size = unpack($DBM::Deep::DATA_LENGTH_PACK, $size);
- if ($size) { seek($fh, $size, SEEK_CUR); }
-
- ##
- # Read in plain key and return as scalar
- ##
- my $plain_key;
- read( $fh, $size, $DBM::Deep::DATA_LENGTH_SIZE); $size = unpack($DBM::Deep::DATA_LENGTH_PACK, $size);
- if ($size) { read( $fh, $plain_key, $size); }
-
- return $plain_key;
- }
- } # bucket loop
-
- $obj->{return_next} = 1;
- } # tag is a bucket list
-
- return;
+sub _throw_error {
+ die "DBM::Deep: $_[1]\n";
}
-sub get_next_key {
- ##
- # Locate next key, given digested previous one
- ##
+sub _get_dbm_object {
+ my $item = shift;
+
+ my $obj = eval {
+ local $SIG{__DIE__};
+ if ($item->isa( 'DBM::Deep' )) {
+ return $item;
+ }
+ return;
+ };
+ return $obj if $obj;
+
+ my $r = Scalar::Util::reftype( $item ) || '';
+ if ( $r eq 'HASH' ) {
+ my $obj = eval {
+ local $SIG{__DIE__};
+ my $obj = tied(%$item);
+ if ($obj->isa( 'DBM::Deep' )) {
+ return $obj;
+ }
+ return;
+ };
+ return $obj if $obj;
+ }
+ elsif ( $r eq 'ARRAY' ) {
+ my $obj = eval {
+ local $SIG{__DIE__};
+ my $obj = tied(@$item);
+ if ($obj->isa( 'DBM::Deep' )) {
+ return $obj;
+ }
+ return;
+ };
+ return $obj if $obj;
+ }
+
+ return;
+}
+
+sub _length_needed {
my $self = shift;
- my ($obj) = @_;
-
- $obj->{prev_md5} = $_[1] ? $_[1] : undef;
- $obj->{return_next} = 0;
-
- ##
- # If the previous key was not specifed, start at the top and
- # return the first one found.
- ##
- if (!$obj->{prev_md5}) {
- $obj->{prev_md5} = chr(0) x $DBM::Deep::HASH_SIZE;
- $obj->{return_next} = 1;
- }
-
- return $self->traverse_index( $obj, $obj->_base_offset, 0 );
+ my ($value, $key) = @_;
+
+ my $is_dbm_deep = eval {
+ local $SIG{'__DIE__'};
+ $value->isa( 'DBM::Deep' );
+ };
+
+ my $len = SIG_SIZE
+ + $self->{data_size} # size for value
+ + $self->{data_size} # size for key
+ + length( $key ); # length of key
+
+ if ( $is_dbm_deep && $value->_storage eq $self->_storage ) {
+ # long_size is for the internal reference
+ return $len + $self->{long_size};
+ }
+
+ if ( $self->_storage->{autobless} ) {
+ # This is for the bit saying whether or not this thing is blessed.
+ $len += 1;
+ }
+
+ my $r = Scalar::Util::reftype( $value ) || '';
+ unless ( $r eq 'HASH' || $r eq 'ARRAY' ) {
+ if ( defined $value ) {
+ $len += length( $value );
+ }
+ return $len;
+ }
+
+ $len += $self->{index_size};
+
+ # if autobless is enabled, must also take into consideration
+ # the class name as it is stored after the key.
+ if ( $self->_storage->{autobless} ) {
+ my $c = Scalar::Util::blessed($value);
+ if ( defined $c && !$is_dbm_deep ) {
+ $len += $self->{data_size} + length($c);
+ }
+ }
+
+ return $len;
}
1;
projects / dbsrgits/DBM-Deep.git / blobdiff