# 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->{index_size} = (2**8) * $self->{long_size};
- $self->{bucket_size} = $self->{hash_size} + $self->{long_size} * 3;
+ $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;
}
};
}
+sub find_keyloc {
+ my $self = shift;
+ my ($tag, $transaction_id) = @_;
+ $transaction_id = $self->_fileobj->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} ),
+ );
+
+ if ( $loc == 0 ) {
+ return ( $loc, $is_deleted, $i * $self->{key_size} );
+ }
+
+ next if $transaction_id != $trans_id;
+
+ return ( $loc, $is_deleted, $i * $self->{key_size} );
+ }
+
+ return;
+}
+
sub add_bucket {
##
# Adds one key/value pair to bucket list, given offset, MD5 digest of key,
##
my $self = shift;
my ($tag, $md5, $plain_key, $value, $deleted, $orig_key) = @_;
- $deleted ||= 0;
# This verifies that only supported values will be stored.
{
my $fileobj = $self->_fileobj;
- my $actual_length = $self->_length_needed( $value, $plain_key );
-
#ACID - This is a mutation. Must only find the exact transaction
- my ($subloc, $offset, $size,$is_deleted) = $self->_find_in_buckets( $tag, $md5, 1 );
+ my ($keyloc, $offset) = $self->_find_in_buckets( $tag, $md5, 1 );
my @transactions;
if ( $fileobj->transaction_id == 0 ) {
}
# $self->_release_space( $size, $subloc );
- # Updating a known md5
#XXX This needs updating to use _release_space
+
my $location;
- if ( $subloc ) {
- if ($actual_length <= $size) {
- $location = $subloc;
- }
- else {
- $location = $fileobj->request_space( $actual_length );
+ my $size = $self->_length_needed( $value, $plain_key );
- $fileobj->print_at( $tag->{offset} + $offset + $self->{hash_size},
- pack($self->{long_pack}, $location ),
- pack($self->{long_pack}, $actual_length ),
- pack('n n', $fileobj->transaction_id, $deleted ),
- );
+ # Updating a known md5
+ if ( $keyloc ) {
+ my $keytag = $self->load_tag( $keyloc );
+ my ($subloc, $is_deleted, $offset) = $self->find_keyloc( $keytag );
+
+ if ( @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 = $fileobj->request_space( $old_size );
+ $fileobj->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 $old_value = $self->read_from_loc( $subloc, $orig_key );
- for ( @transactions ) {
- my $tag2 = $self->load_tag( $tag->{offset} - SIG_SIZE - $self->{data_size} );
- $fileobj->{transaction_id} = $_;
- $self->add_bucket( $tag2, $md5, $orig_key, $old_value, undef, $orig_key );
- $fileobj->{transaction_id} = 0;
- }
- $tag = $self->load_tag( $tag->{offset} - SIG_SIZE - $self->{data_size} );
+ $location = $self->_fileobj->request_space( $size );
+ #XXX This needs to be transactionally-aware in terms of which keytag->{offset} to use
+ $fileobj->print_at( $keytag->{offset} + $offset,
+ pack($self->{long_pack}, $location ),
+ pack( 'C C', $fileobj->transaction_id, 0 ),
+ );
}
# Adding a new md5
- elsif ( defined $offset ) {
- $location = $fileobj->request_space( $actual_length );
+ else {
+ my $keyloc = $fileobj->request_space( $self->tag_size( $self->{keyloc_size} ) );
- $fileobj->print_at( $tag->{offset} + $offset,
- $md5,
- pack($self->{long_pack}, $location ),
- pack($self->{long_pack}, $actual_length ),
- pack('n n', $fileobj->transaction_id, $deleted ),
+ # The bucket fit into list
+ if ( defined $offset ) {
+ $fileobj->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 );
+ }
+
+ my $keytag = $self->write_tag(
+ $keyloc, SIG_KEYS, chr(0)x$self->{keyloc_size},
);
- for ( @transactions ) {
- my $tag2 = $self->load_tag( $tag->{offset} - SIG_SIZE - $self->{data_size} );
- $fileobj->{transaction_id} = $_;
- $self->add_bucket( $tag2, $md5, '', '', 1, $orig_key );
- $fileobj->{transaction_id} = 0;
+ $location = $self->_fileobj->request_space( $size );
+ $fileobj->print_at( $keytag->{offset},
+ pack( $self->{long_pack}, $location ),
+ pack( 'C C', $fileobj->transaction_id, 0 ),
+ );
+
+ my $offset = 1;
+ for my $trans_id ( @transactions ) {
+ $fileobj->print_at( $keytag->{offset} + $self->{key_size} * $offset++,
+ pack( $self->{long_pack}, -1 ),
+ pack( 'C C', $trans_id, 1 ),
+ );
}
- $tag = $self->load_tag( $tag->{offset} - SIG_SIZE - $self->{data_size} );
- }
- # If bucket didn't fit into list, split into a new index level
- # split_index() will do the $self->_fileobj->request_space() call
- #XXX It also needs to be transactionally aware
- else {
- $location = $self->split_index( $md5, $tag );
}
$self->write_value( $location, $plain_key, $value, $orig_key );
sub split_index {
my $self = shift;
- my ($md5, $tag) = @_;
+ my ($tag, $md5, $keyloc) = @_;
my $fileobj = $self->_fileobj;
chr(0)x$self->{index_size},
);
- my $newtag_loc = $fileobj->request_space(
- $self->tag_size( $self->{bucket_list_size} ),
- );
-
my $keys = $tag->{content}
- . $md5 . pack($self->{long_pack}, $newtag_loc)
- . pack($self->{long_pack}, 0) # size
- . pack($self->{long_pack}, 0); # transaction ID
+ . $md5 . pack($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, $size) = $self->_get_key_subloc( $keys, $i );
+ my ($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 $subkeys = $fileobj->read_at( $newloc[$num], $self->{bucket_list_size} );
# This is looking for the first empty spot
- my ($subloc, $offset, $size) = $self->_find_in_buckets(
+ my ($subloc, $offset) = $self->_find_in_buckets(
{ content => $subkeys }, '',
);
$tag->{offset} - SIG_SIZE - $self->{data_size},
);
- return $newtag_loc;
+ return 1;
}
sub read_from_loc {
my ($tag, $md5, $orig_key) = @_;
#ACID - This is a read. Can find exact or HEAD
- my ($subloc, $offset, $size, $is_deleted) = $self->_find_in_buckets( $tag, $md5 );
+ my ($keyloc, $offset) = $self->_find_in_buckets( $tag, $md5 );
- if ( !$subloc ) {
+ if ( !$keyloc ) {
#XXX Need to use real key
-# $self->add_bucket( $tag, $md5, $orig_key, undef, undef, $orig_key );
+# $self->add_bucket( $tag, $md5, $orig_key, undef, $orig_key );
# return;
}
- elsif ( !$is_deleted ) {
- return $self->read_from_loc( $subloc, $orig_key );
+# elsif ( !$is_deleted ) {
+ else {
+ my $keytag = $self->load_tag( $keyloc );
+ my ($subloc, $is_deleted) = $self->find_keyloc( $keytag );
+ if (!$subloc) {
+ ($subloc, $is_deleted) = $self->find_keyloc( $keytag, 0 );
+ }
+ if ( $subloc && !$is_deleted ) {
+ return $self->read_from_loc( $subloc, $orig_key );
+ }
}
return;
#ACID - Although this is a mutation, we must find any transaction.
# This is because we need to mark something as deleted that is in the HEAD.
- my ($subloc, $offset, $size,$is_deleted) = $self->_find_in_buckets( $tag, $md5 );
+ my ($keyloc, $offset) = $self->_find_in_buckets( $tag, $md5 );
- return if !$subloc;
+ return if !$keyloc;
my $fileobj = $self->_fileobj;
}
if ( $fileobj->transaction_id == 0 ) {
+ my $keytag = $self->load_tag( $keyloc );
+ my ($subloc, $is_deleted, $offset) = $self->find_keyloc( $keytag );
my $value = $self->read_from_loc( $subloc, $orig_key );
- for (@transactions) {
- $fileobj->{transaction_id} = $_;
- #XXX Need to use real key
- $self->add_bucket( $tag, $md5, $orig_key, $value, undef, $orig_key );
- $fileobj->{transaction_id} = 0;
+ 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 = $fileobj->request_space( $size );
+ $fileobj->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 );
+ }
}
- $tag = $self->load_tag( $tag->{offset} - SIG_SIZE - $self->{data_size} );
- #XXX This needs _release_space() for the value and anything below
- $fileobj->print_at(
- $tag->{offset} + $offset,
- substr( $tag->{content}, $offset + $self->{bucket_size} ),
- chr(0) x $self->{bucket_size},
+ $keytag = $self->load_tag( $keyloc );
+ ($subloc, $is_deleted, $offset) = $self->find_keyloc( $keytag );
+ $fileobj->print_at( $keytag->{offset} + $offset,
+ substr( $keytag->{content}, $offset + $self->{key_size} ),
+ chr(0) x $self->{key_size},
);
}
else {
- $self->add_bucket( $tag, $md5, '', '', 1, $orig_key );
+ my $keytag = $self->load_tag( $keyloc );
+ my ($subloc, $is_deleted, $offset) = $self->find_keyloc( $keytag );
+ $fileobj->print_at( $keytag->{offset} + $offset,
+ pack($self->{long_pack}, -1 ),
+ pack( 'C C', $fileobj->transaction_id, 1 ),
+ );
}
return 1;
my ($tag, $md5) = @_;
#ACID - This is a read. Can find exact or HEAD
- my ($subloc, $offset, $size, $is_deleted) = $self->_find_in_buckets( $tag, $md5 );
+ my ($keyloc) = $self->_find_in_buckets( $tag, $md5 );
+ my $keytag = $self->load_tag( $keyloc );
+ my ($subloc, $is_deleted, $offset) = $self->find_keyloc( $keytag );
+ if ( !$subloc ) {
+ ($subloc, $is_deleted, $offset) = $self->find_keyloc( $keytag, 0 );
+ }
return ($subloc && !$is_deleted) && 1;
}
# Scan index and recursively step into deeper levels, looking for next key.
##
my $self = shift;
- my ($obj, $offset, $ch, $force_return_next) = @_;
+ my ($xxxx, $offset, $ch, $force_return_next) = @_;
my $tag = $self->load_tag( $offset );
if ($tag->{signature} ne SIG_BLIST) {
- my $content = $tag->{content};
- my $start = $obj->{return_next} ? 0 : ord(substr($obj->{prev_md5}, $ch, 1));
+ my $start = $xxxx->{return_next} ? 0 : ord(substr($xxxx->{prev_md5}, $ch, 1));
- for (my $idx = $start; $idx < (2**8); $idx++) {
+ for (my $idx = $start; $idx < $self->{hash_chars_used}; $idx++) {
my $subloc = unpack(
$self->{long_pack},
substr(
- $content,
+ $tag->{content},
$idx * $self->{long_size},
$self->{long_size},
),
if ($subloc) {
my $result = $self->traverse_index(
- $obj, $subloc, $ch + 1, $force_return_next,
+ $xxxx, $subloc, $ch + 1, $force_return_next,
);
- if (defined($result)) { return $result; }
+ if (defined $result) { return $result; }
}
} # index loop
- $obj->{return_next} = 1;
+ $xxxx->{return_next} = 1;
}
# This is the bucket list
else {
my $keys = $tag->{content};
- if ($force_return_next) { $obj->{return_next} = 1; }
+ if ($force_return_next) { $xxxx->{return_next} = 1; }
##
# Iterate through buckets, looking for a key match
##
my $transaction_id = $self->_fileobj->transaction_id;
for (my $i = 0; $i < $self->{max_buckets}; $i++) {
- my ($key, $subloc, $size, $trans_id, $is_deleted) = $self->_get_key_subloc( $keys, $i );
-
- next if $is_deleted;
-#XXX Need to find all the copies of this key to find out if $transaction_id has it
-#XXX marked as deleted, in use, or what.
- next if $trans_id && $trans_id != $transaction_id;
+ my ($key, $keyloc) = $self->_get_key_subloc( $keys, $i );
# End of bucket list -- return to outer loop
- if (!$subloc) {
- $obj->{return_next} = 1;
+ if (!$keyloc) {
+ $xxxx->{return_next} = 1;
last;
}
# Located previous key -- return next one found
- elsif ($key eq $obj->{prev_md5}) {
- $obj->{return_next} = 1;
+ elsif ($key eq $xxxx->{prev_md5}) {
+ $xxxx->{return_next} = 1;
next;
}
# Seek to bucket location and skip over signature
- elsif ($obj->{return_next}) {
+ elsif ($xxxx->{return_next}) {
my $fileobj = $self->_fileobj;
+ my $keytag = $self->load_tag( $keyloc );
+ my ($subloc, $is_deleted) = $self->find_keyloc( $keytag );
+ if ( $subloc == 0 ) {
+ ($subloc, $is_deleted) = $self->find_keyloc( $keytag, 0 );
+ }
+ next if $is_deleted;
+
# Skip over value to get to plain key
my $sig = $fileobj->read_at( $subloc, SIG_SIZE );
}
}
- $obj->{return_next} = 1;
+ $xxxx->{return_next} = 1;
}
return;
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 $self->{hash_size};
- $obj->{return_next} = 1;
+ my $temp;
+ if ( @_ > 1 ) {
+ $temp = {
+ prev_md5 => $_[1],
+ return_next => 0,
+ };
+ }
+ else {
+ $temp = {
+ prev_md5 => chr(0) x $self->{hash_size},
+ return_next => 1,
+ };
}
- return $self->traverse_index( $obj, $obj->_base_offset, 0 );
+ return $self->traverse_index( $temp, $obj->_base_offset, 0 );
}
# Utilities
my $self = shift;
my ($keys, $idx) = @_;
- my ($key, $subloc, $size, $transaction_id, $is_deleted) = unpack(
+ return unpack(
# This is 'a', not 'A'. Please read the pack() documentation for the
# difference between the two and why it's important.
- "a$self->{hash_size} $self->{long_pack}2 n2",
+ "a$self->{hash_size} $self->{long_pack}",
substr(
$keys,
($idx * $self->{bucket_size}),
$self->{bucket_size},
),
);
-
- return ($key, $subloc, $size, $transaction_id, $is_deleted);
}
sub _find_in_buckets {
my $self = shift;
- my ($tag, $md5, $exact) = @_;
- $exact ||= 0;
-
- my $trans_id = $self->_fileobj->transaction_id;
-
- my @zero;
+ my ($tag, $md5) = @_;
BUCKET:
for ( my $i = 0; $i < $self->{max_buckets}; $i++ ) {
- my ($key, $subloc, $size, $transaction_id, $is_deleted) = $self->_get_key_subloc(
+ my ($key, $subloc) = $self->_get_key_subloc(
$tag->{content}, $i,
);
- my @rv = ($subloc, $i * $self->{bucket_size}, $size, $is_deleted);
+ my @rv = ($subloc, $i * $self->{bucket_size});
unless ( $subloc ) {
- if ( !$exact && @zero && $trans_id ) {
- @rv = ($zero[2], $zero[0] * $self->{bucket_size},$zero[3],$is_deleted);
- }
return @rv;
}
next BUCKET if $key ne $md5;
- # Save off the HEAD in case we need it.
- @zero = ($i,$key,$subloc,$size,$transaction_id,$is_deleted) if $transaction_id == 0;
-
- next BUCKET if $transaction_id != $trans_id;
-
return @rv;
}
projects / dbsrgits/DBM-Deep.git / blobdiff