use warnings;
use Fcntl qw( :DEFAULT :flock :seek );
+use Scalar::Util ();
+
+# File-wide notes:
+# * All the local($/,$\); are to protect read() and print() from -l.
+# * To add to bucket_size, make sure you modify the following:
+# - calculate_sizes()
+# - _get_key_subloc()
+# - add_bucket() - where the buckets are printed
##
# Setup file and tag signatures. These should never change.
max_buckets => 16,
fileobj => undef,
+ obj => undef,
}, $class;
if ( defined $args->{pack_size} ) {
if ( lc $args->{pack_size} eq 'small' ) {
$args->{long_size} = 2;
- $args->{long_pack} = 'S';
+ $args->{long_pack} = 'n';
}
elsif ( lc $args->{pack_size} eq 'medium' ) {
$args->{long_size} = 4;
next unless exists $args->{$param};
$self->{$param} = $args->{$param};
}
+ Scalar::Util::weaken( $self->{obj} ) if $self->{obj};
if ( $self->{max_buckets} < 16 ) {
warn "Floor of max_buckets is 16. Setting it to 16 from '$self->{max_buckets}'\n";
sub calculate_sizes {
my $self = shift;
+ #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} * 2;
+ $self->{bucket_size} = $self->{hash_size} + $self->{long_size} * 3;
$self->{bucket_list_size} = $self->{max_buckets} * $self->{bucket_size};
return;
sub write_file_header {
my $self = shift;
-# my ($obj) = @_;
+
+ local($/,$\);
my $fh = $self->_fh;
- my $loc = $self->_request_space(
- undef, length( SIG_FILE ) + 21,
- );
+ my $loc = $self->_request_space( length( SIG_FILE ) + 21 );
seek($fh, $loc + $self->_fileobj->{file_offset}, SEEK_SET);
print( $fh
SIG_FILE,
SIG_HEADER,
pack('N', 1), # header version
pack('N', 12), # header size
- pack('N', 0), # file version
- pack('S', $self->{long_size}),
+ pack('N', 0), # currently running transaction IDs
+ pack('n', $self->{long_size}),
pack('A', $self->{long_pack}),
- pack('S', $self->{data_size}),
+ pack('n', $self->{data_size}),
pack('A', $self->{data_pack}),
- pack('S', $self->{max_buckets}),
+ pack('n', $self->{max_buckets}),
);
+ $self->_fileobj->set_transaction_offset( 13 );
+
return;
}
sub read_file_header {
my $self = shift;
- my ($obj) = @_;
- my $fh = $obj->_fh;
+ local($/,$\);
+
+ my $fh = $self->_fh;
- seek($fh, 0 + $obj->_fileobj->{file_offset}, SEEK_SET);
+ seek($fh, 0 + $self->_fileobj->{file_offset}, SEEK_SET);
my $buffer;
my $bytes_read = read( $fh, $buffer, length(SIG_FILE) + 9 );
);
unless ( $file_signature eq SIG_FILE ) {
- $self->{fileobj}->close;
- $obj->_throw_error( "Signature not found -- file is not a Deep DB" );
+ $self->_fileobj->close;
+ $self->_throw_error( "Signature not found -- file is not a Deep DB" );
}
unless ( $sig_header eq SIG_HEADER ) {
- $self->{fileobj}->close;
- $obj->_throw_error( "Old file version found." );
+ $self->_fileobj->close;
+ $self->_throw_error( "Old file version found." );
}
my $buffer2;
$bytes_read += read( $fh, $buffer2, $size );
- my ($file_version, @values) = unpack( 'N S A S A S', $buffer2 );
+ my ($running_transactions, @values) = unpack( 'N n A n A n', $buffer2 );
+
+ $self->_fileobj->set_transaction_offset( 13 );
+
if ( @values < 5 || grep { !defined } @values ) {
- $self->{fileobj}->close;
- $obj->_throw_error("Corrupted file - bad header");
+ $self->_fileobj->close;
+ $self->_throw_error("Corrupted file - bad header");
}
#XXX Add warnings if values weren't set right
return $bytes_read;
}
-sub get_file_version {
- my $self = shift;
- my ($obj) = @_;
-
- my $fh = $obj->_fh;
-
- seek( $fh, 13 + $obj->_fileobj->{file_offset}, SEEK_SET );
- my $buffer;
- my $bytes_read = read( $fh, $buffer, 4 );
- unless ( $bytes_read == 4 ) {
- $obj->_throw_error( "Cannot read file version" );
- }
-
- return unpack( 'N', $buffer );
-}
-
-sub write_file_version {
- my $self = shift;
- my ($obj, $new_version) = @_;
-
- my $fh = $obj->_fh;
-
- seek( $fh, 13 + $obj->_fileobj->{file_offset}, SEEK_SET );
- print( $fh pack( 'N', $new_version ) );
-
- return;
-}
-
sub setup_fh {
my $self = shift;
my ($obj) = @_;
- my $fh = $obj->_fh;
+ local($/,$\);
+
+ my $fh = $self->_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( $obj );
+ my $bytes_read = $self->read_file_header;
$self->calculate_sizes;
# File is empty -- write header and master index
##
if (!$bytes_read) {
- $self->write_file_header( $obj );
+ $self->_fileobj->audit( "# Database created on" );
- $obj->{base_offset} = $self->_request_space(
- $obj, $self->tag_size( $self->{index_size} ),
- );
+ $self->write_file_header;
+
+ $obj->{base_offset} = $self->_request_space( $self->tag_size( $self->{index_size} ) );
$self->write_tag(
- $obj, $obj->_base_offset, $obj->_type,
+ $obj->_base_offset, $obj->_type,
chr(0)x$self->{index_size},
);
##
# Get our type from master index header
##
- my $tag = $self->load_tag($obj, $obj->_base_offset)
- or $obj->_throw_error("Corrupted file, no master index record");
+ 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}) {
- $obj->_throw_error("File type mismatch");
+ unless ($obj->_type eq $tag->{signature}) {
+ flock $fh, LOCK_UN;
+ $self->_throw_error("File type mismatch");
}
}
}
}
#XXX We have to make sure we don't mess up when autoflush isn't turned on
- unless ( $obj->_fileobj->{inode} ) {
- my @stats = stat($obj->_fh);
- $obj->_fileobj->{inode} = $stats[1];
- $obj->_fileobj->{end} = $stats[7];
+ unless ( $self->_fileobj->{inode} ) {
+ my @stats = stat($fh);
+ $self->_fileobj->{inode} = $stats[1];
+ $self->_fileobj->{end} = $stats[7];
}
flock $fh, LOCK_UN;
# Given offset, signature and content, create tag and write to disk
##
my $self = shift;
- my ($obj, $offset, $sig, $content) = @_;
+ my ($offset, $sig, $content) = @_;
my $size = length( $content );
- my $fh = $obj->_fh;
+ local($/,$\);
+
+ my $fh = $self->_fh;
if ( defined $offset ) {
- seek($fh, $offset + $obj->_fileobj->{file_offset}, SEEK_SET);
+ seek($fh, $offset + $self->_fileobj->{file_offset}, SEEK_SET);
}
print( $fh $sig . pack($self->{data_pack}, $size) . $content );
# Given offset, load single tag and return signature, size and data
##
my $self = shift;
- my ($obj, $offset) = @_;
+ my ($offset) = @_;
+
+ local($/,$\);
# print join(':',map{$_||''}caller(1)), $/;
- my $fh = $obj->_fh;
+ my $fh = $self->_fh;
- seek($fh, $offset + $obj->_fileobj->{file_offset}, SEEK_SET);
+ seek($fh, $offset + $self->_fileobj->{file_offset}, SEEK_SET);
#XXX I'm not sure this check will work if autoflush isn't enabled ...
return if eof $fh;
sub _length_needed {
my $self = shift;
- my ($obj, $value, $key) = @_;
+ my ($value, $key) = @_;
my $is_dbm_deep = eval {
local $SIG{'__DIE__'};
my $len = SIG_SIZE + $self->{data_size}
+ $self->{data_size} + length( $key );
- if ( $is_dbm_deep && $value->_fileobj eq $obj->_fileobj ) {
+ if ( $is_dbm_deep && $value->_fileobj eq $self->_fileobj ) {
return $len + $self->{long_size};
}
my $r = Scalar::Util::reftype( $value ) || '';
- if ( $obj->_fileobj->{autobless} ) {
+ if ( $self->_fileobj->{autobless} ) {
# This is for the bit saying whether or not this thing is blessed.
$len += 1;
}
# if autobless is enabled, must also take into consideration
# the class name as it is stored after the key.
- if ( $obj->_fileobj->{autobless} ) {
+ if ( $self->_fileobj->{autobless} ) {
my $c = Scalar::Util::blessed($value);
if ( defined $c && !$is_dbm_deep ) {
$len += $self->{data_size} + length($c);
# plain (undigested) key and value.
##
my $self = shift;
- my ($obj, $tag, $md5, $plain_key, $value) = @_;
+ my ($tag, $md5, $plain_key, $value, $deleted, $orig_key) = @_;
+ $deleted ||= 0;
+
+ local($/,$\);
# This verifies that only supported values will be stored.
{
last if $r eq 'HASH';
last if $r eq 'ARRAY';
- $obj->_throw_error(
+ $self->_throw_error(
"Storage of variables of type '$r' is not supported."
);
}
my $location = 0;
my $result = 2;
- my $root = $obj->_fileobj;
- my $fh = $obj->_fh;
+ my $root = $self->_fileobj;
+ my $fh = $self->_fh;
+
+ my $actual_length = $self->_length_needed( $value, $plain_key );
- my $actual_length = $self->_length_needed( $obj, $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, $md5, 1 );
- my ($subloc, $offset, $size) = $self->_find_in_buckets( $tag, $md5 );
+ my @transactions;
+ if ( $self->_fileobj->transaction_id == 0 ) {
+ @transactions = $self->_fileobj->current_transactions;
+ }
-# $self->_release_space( $obj, $size, $subloc );
+# $self->_release_space( $size, $subloc );
# Updating a known md5
#XXX This needs updating to use _release_space
if ( $subloc ) {
$location = $subloc;
}
else {
- $location = $self->_request_space( $obj, $actual_length );
+ $location = $self->_request_space( $actual_length );
seek(
$fh,
$tag->{offset} + $offset
);
print( $fh pack($self->{long_pack}, $location ) );
print( $fh pack($self->{long_pack}, $actual_length ) );
+ print( $fh pack('n n', $root->transaction_id, $deleted ) );
}
}
# Adding a new md5
elsif ( defined $offset ) {
- $location = $self->_request_space( $obj, $actual_length );
+ $location = $self->_request_space( $actual_length );
seek( $fh, $tag->{offset} + $offset + $root->{file_offset}, SEEK_SET );
print( $fh $md5 . pack($self->{long_pack}, $location ) );
print( $fh pack($self->{long_pack}, $actual_length ) );
+ print( $fh pack('n n', $root->transaction_id, $deleted ) );
+
+ for ( @transactions ) {
+ my $tag2 = $self->load_tag( $tag->{offset} - SIG_SIZE - $self->{data_size} );
+ $self->_fileobj->{transaction_id} = $_;
+ $self->add_bucket( $tag2, $md5, '', '', 1, $orig_key );
+ $self->_fileobj->{transaction_id} = 0;
+ }
}
# If bucket didn't fit into list, split into a new index level
# split_index() will do the _request_space() call
else {
- $location = $self->split_index( $obj, $md5, $tag );
+ $location = $self->split_index( $md5, $tag );
}
- $self->write_value( $obj, $location, $plain_key, $value );
+ $self->write_value( $location, $plain_key, $value, $orig_key );
return $result;
}
sub write_value {
my $self = shift;
- my ($obj, $location, $key, $value) = @_;
+ my ($location, $key, $value, $orig_key) = @_;
+
+ local($/,$\);
- my $fh = $obj->_fh;
- my $root = $obj->_fileobj;
+ my $fh = $self->_fh;
+ my $root = $self->_fileobj;
my $dbm_deep_obj = _get_dbm_object( $value );
- if ( $dbm_deep_obj && $dbm_deep_obj->_fileobj ne $obj->_fileobj ) {
- $obj->_throw_error( "Cannot cross-reference. Use export() instead" );
+ if ( $dbm_deep_obj && $dbm_deep_obj->_fileobj ne $self->_fileobj ) {
+ $self->_throw_error( "Cannot cross-reference. Use export() instead" );
}
seek($fh, $location + $root->{file_offset}, SEEK_SET);
##
my $r = Scalar::Util::reftype( $value ) || '';
if ( $dbm_deep_obj ) {
- $self->write_tag( $obj, undef, SIG_INTERNAL,pack($self->{long_pack}, $dbm_deep_obj->_base_offset) );
+ $self->write_tag( undef, SIG_INTERNAL,pack($self->{long_pack}, $dbm_deep_obj->_base_offset) );
}
elsif ($r eq 'HASH') {
if ( !$dbm_deep_obj && tied %{$value} ) {
- $obj->_throw_error( "Cannot store something that is tied" );
+ $self->_throw_error( "Cannot store something that is tied" );
}
- $self->write_tag( $obj, undef, SIG_HASH, chr(0)x$self->{index_size} );
+ $self->write_tag( undef, SIG_HASH, chr(0)x$self->{index_size} );
}
elsif ($r eq 'ARRAY') {
if ( !$dbm_deep_obj && tied @{$value} ) {
- $obj->_throw_error( "Cannot store something that is tied" );
+ $self->_throw_error( "Cannot store something that is tied" );
}
- $self->write_tag( $obj, undef, SIG_ARRAY, chr(0)x$self->{index_size} );
+ $self->write_tag( undef, SIG_ARRAY, chr(0)x$self->{index_size} );
}
elsif (!defined($value)) {
- $self->write_tag( $obj, undef, SIG_NULL, '' );
+ $self->write_tag( undef, SIG_NULL, '' );
}
else {
- $self->write_tag( $obj, undef, SIG_DATA, $value );
+ $self->write_tag( undef, SIG_DATA, $value );
}
##
tie %$value, 'DBM::Deep', {
base_offset => $location,
fileobj => $root,
+ parent => $self->{obj},
+ parent_key => $orig_key,
};
%$value = %x;
}
tie @$value, 'DBM::Deep', {
base_offset => $location,
fileobj => $root,
+ parent => $self->{obj},
+ parent_key => $orig_key,
};
@$value = @x;
}
sub split_index {
my $self = shift;
- my ($obj, $md5, $tag) = @_;
+ my ($md5, $tag) = @_;
- my $fh = $obj->_fh;
- my $root = $obj->_fileobj;
+ local($/,$\);
+
+ my $fh = $self->_fh;
+ my $root = $self->_fileobj;
my $loc = $self->_request_space(
- $obj, $self->tag_size( $self->{index_size} ),
+ $self->tag_size( $self->{index_size} ),
);
seek($fh, $tag->{ref_loc} + $root->{file_offset}, SEEK_SET);
print( $fh pack($self->{long_pack}, $loc) );
my $index_tag = $self->write_tag(
- $obj, $loc, SIG_INDEX,
+ $loc, SIG_INDEX,
chr(0)x$self->{index_size},
);
my $newtag_loc = $self->_request_space(
- $obj, $self->tag_size( $self->{bucket_list_size} ),
+ $self->tag_size( $self->{bucket_list_size} ),
);
my $keys = $tag->{content}
. $md5 . pack($self->{long_pack}, $newtag_loc)
- . pack($self->{long_pack}, 0);
+ . pack($self->{long_pack}, 0) # size
+ . pack($self->{long_pack}, 0); # transaction ID
my @newloc = ();
BUCKET:
seek($fh, $index_tag->{offset} + ($num * $self->{long_size}) + $root->{file_offset}, SEEK_SET);
my $loc = $self->_request_space(
- $obj, $self->tag_size( $self->{bucket_list_size} ),
+ $self->tag_size( $self->{bucket_list_size} ),
);
print( $fh pack($self->{long_pack}, $loc) );
my $blist_tag = $self->write_tag(
- $obj, $loc, SIG_BLIST,
+ $loc, SIG_BLIST,
chr(0)x$self->{bucket_list_size},
);
}
$self->_release_space(
- $obj, $self->tag_size( $self->{bucket_list_size} ),
+ $self->tag_size( $self->{bucket_list_size} ),
$tag->{offset} - SIG_SIZE - $self->{data_size},
);
sub read_from_loc {
my $self = shift;
- my ($obj, $subloc) = @_;
+ my ($subloc, $orig_key) = @_;
+
+ local($/,$\);
- my $fh = $obj->_fh;
+ my $fh = $self->_fh;
##
# Found match -- seek to offset and read signature
##
my $signature;
- seek($fh, $subloc + $obj->_fileobj->{file_offset}, SEEK_SET);
+ seek($fh, $subloc + $self->_fileobj->{file_offset}, SEEK_SET);
read( $fh, $signature, SIG_SIZE);
##
##
if (($signature eq SIG_HASH) || ($signature eq SIG_ARRAY)) {
my $new_obj = DBM::Deep->new({
- type => $signature,
+ type => $signature,
base_offset => $subloc,
- fileobj => $obj->_fileobj,
+ fileobj => $self->_fileobj,
+ parent => $self->{obj},
+ parent_key => $orig_key,
});
if ($new_obj->_fileobj->{autobless}) {
read( $fh, $new_loc, $size );
$new_loc = unpack( $self->{long_pack}, $new_loc );
- return $self->read_from_loc( $obj, $new_loc );
+ return $self->read_from_loc( $new_loc, $orig_key );
}
else {
return;
# Fetch single value given tag and MD5 digested key.
##
my $self = shift;
- my ($obj, $tag, $md5) = @_;
+ my ($tag, $md5, $orig_key) = @_;
- my ($subloc, $offset, $size) = $self->_find_in_buckets( $tag, $md5 );
- if ( $subloc ) {
- return $self->read_from_loc( $obj, $subloc );
+ #ACID - This is a read. Can find exact or HEAD
+ my ($subloc, $offset, $size,$is_deleted) = $self->_find_in_buckets( $tag, $md5 );
+ if ( $subloc && !$is_deleted ) {
+ return $self->read_from_loc( $subloc, $orig_key );
}
return;
}
# Delete single key/value pair given tag and MD5 digested key.
##
my $self = shift;
- my ($obj, $tag, $md5) = @_;
+ my ($tag, $md5, $orig_key) = @_;
+
+ local($/,$\);
- my ($subloc, $offset, $size) = $self->_find_in_buckets( $tag, $md5 );
+ #ACID - This is a mutation. Must only find the exact transaction
+ my ($subloc, $offset, $size) = $self->_find_in_buckets( $tag, $md5, 1 );
#XXX This needs _release_space()
if ( $subloc ) {
- my $fh = $obj->_fh;
- seek($fh, $tag->{offset} + $offset + $obj->_fileobj->{file_offset}, SEEK_SET);
+ my $fh = $self->_fh;
+ seek($fh, $tag->{offset} + $offset + $self->_fileobj->{file_offset}, SEEK_SET);
print( $fh substr($tag->{content}, $offset + $self->{bucket_size} ) );
print( $fh chr(0) x $self->{bucket_size} );
# Check existence of single key given tag and MD5 digested key.
##
my $self = shift;
- my ($obj, $tag, $md5) = @_;
+ my ($tag, $md5) = @_;
- my ($subloc, $offset, $size) = $self->_find_in_buckets( $tag, $md5 );
- return $subloc && 1;
+ #ACID - This is a read. Can find exact or HEAD
+ my ($subloc, $offset, $size, $is_deleted) = $self->_find_in_buckets( $tag, $md5 );
+ return ($subloc && !$is_deleted) && 1;
}
sub find_bucket_list {
# Locate offset for bucket list, given digested key
##
my $self = shift;
- my ($obj, $md5, $args) = @_;
+ my ($offset, $md5, $args) = @_;
$args = {} unless $args;
+ local($/,$\);
+
##
# Locate offset for bucket list using digest index system
##
- my $tag = $self->load_tag($obj, $obj->_base_offset)
- or $obj->_throw_error( "INTERNAL ERROR - Cannot find tag" );
+ my $tag = $self->load_tag( $offset )
+ or $self->_throw_error( "INTERNAL ERROR - Cannot find tag" );
my $ch = 0;
while ($tag->{signature} ne SIG_BLIST) {
my $num = ord substr($md5, $ch, 1);
my $ref_loc = $tag->{offset} + ($num * $self->{long_size});
- $tag = $self->index_lookup( $obj, $tag, $num );
+ $tag = $self->index_lookup( $tag, $num );
if (!$tag) {
return if !$args->{create};
my $loc = $self->_request_space(
- $obj, $self->tag_size( $self->{bucket_list_size} ),
+ $self->tag_size( $self->{bucket_list_size} ),
);
- my $fh = $obj->_fh;
- seek($fh, $ref_loc + $obj->_fileobj->{file_offset}, SEEK_SET);
+ my $fh = $self->_fh;
+ seek($fh, $ref_loc + $self->_fileobj->{file_offset}, SEEK_SET);
print( $fh pack($self->{long_pack}, $loc) );
$tag = $self->write_tag(
- $obj, $loc, SIG_BLIST,
+ $loc, SIG_BLIST,
chr(0)x$self->{bucket_list_size},
);
# Given index tag, lookup single entry in index and return .
##
my $self = shift;
- my ($obj, $tag, $index) = @_;
+ my ($tag, $index) = @_;
my $location = unpack(
$self->{long_pack},
if (!$location) { return; }
- return $self->load_tag( $obj, $location );
+ return $self->load_tag( $location );
}
sub traverse_index {
my $self = shift;
my ($obj, $offset, $ch, $force_return_next) = @_;
- my $tag = $self->load_tag($obj, $offset );
+ local($/,$\);
- my $fh = $obj->_fh;
+ my $tag = $self->load_tag( $offset );
+
+ my $fh = $self->_fh;
if ($tag->{signature} ne SIG_BLIST) {
my $content = $tag->{content};
}
# Seek to bucket location and skip over signature
elsif ($obj->{return_next}) {
- seek($fh, $subloc + $obj->_fileobj->{file_offset}, SEEK_SET);
+ seek($fh, $subloc + $self->_fileobj->{file_offset}, SEEK_SET);
# Skip over value to get to plain key
my $sig;
my $self = shift;
my ($keys, $idx) = @_;
- my ($key, $subloc, $size) = unpack(
- "a$self->{hash_size} $self->{long_pack} $self->{long_pack}",
+ my ($key, $subloc, $size, $transaction_id, $is_deleted) = unpack(
+ # This is 'a', not 'A'. Please read the pack() documentation for the
+ # difference between the two and why it's important.
+ "a$self->{hash_size} $self->{long_pack}2 n2",
substr(
$keys,
($idx * $self->{bucket_size}),
),
);
- return ($key, $subloc, $size);
+ return ($key, $subloc, $size, $transaction_id, $is_deleted);
}
sub _find_in_buckets {
my $self = shift;
- my ($tag, $md5) = @_;
+ my ($tag, $md5, $exact) = @_;
+
+ my $trans_id = $self->_fileobj->transaction_id;
+
+ my @zero;
BUCKET:
for ( my $i = 0; $i < $self->{max_buckets}; $i++ ) {
- my ($key, $subloc, $size) = $self->_get_key_subloc(
+ my ($key, $subloc, $size, $transaction_id, $is_deleted) = $self->_get_key_subloc(
$tag->{content}, $i,
);
- return ($subloc, $i * $self->{bucket_size}, $size) unless $subloc;
+ my @rv = ($subloc, $i * $self->{bucket_size}, $size, $is_deleted);
+
+ unless ( $subloc ) {
+ if ( !$exact && @zero and $trans_id ) {
+ @rv = ($zero[2], $zero[0] * $self->{bucket_size},$zero[3],$is_deleted);
+ }
+ return @rv;
+ }
next BUCKET if $key ne $md5;
- return ($subloc, $i * $self->{bucket_size}, $size);
+ # Save off the HEAD in case we need it.
+ @zero = ($i,$key,$subloc,$size,$transaction_id,$is_deleted) if $transaction_id == 0;
+
+ next BUCKET if $transaction_id != $trans_id;
+
+ return @rv;
}
return;
}
-#sub _print_at {
-# my $self = shift;
-# my ($obj, $spot, $data) = @_;
-#
-# my $fh = $obj->_fh;
-# seek( $fh, $spot, SEEK_SET );
-# print( $fh $data );
-#
-# return;
-#}
-
sub _request_space {
my $self = shift;
- my ($obj, $size) = @_;
+ my ($size) = @_;
my $loc = $self->_fileobj->{end};
$self->_fileobj->{end} += $size;
sub _release_space {
my $self = shift;
- my ($obj, $size, $loc) = @_;
+ my ($size, $loc) = @_;
+
+ local($/,$\);
my $next_loc = 0;
- my $fh = $obj->_fh;
- seek( $fh, $loc + $obj->_fileobj->{file_offset}, SEEK_SET );
+ my $fh = $self->_fh;
+ seek( $fh, $loc + $self->_fileobj->{file_offset}, SEEK_SET );
print( $fh SIG_FREE
. pack($self->{long_pack}, $size )
. pack($self->{long_pack}, $next_loc )
return;
}
+sub _throw_error {
+ die "DBM::Deep: $_[1]\n";
+}
+
1;
__END__
# attempt at refactoring on the physical level instead of the virtual level.
sub _read_at {
my $self = shift;
- my ($obj, $spot, $amount, $unpack) = @_;
+ my ($spot, $amount, $unpack) = @_;
- my $fh = $obj->_fh;
- seek( $fh, $spot + $obj->_fileobj->{file_offset}, SEEK_SET );
+ local($/,$\);
+
+ my $fh = $self->_fh;
+ seek( $fh, $spot + $self->_fileobj->{file_offset}, SEEK_SET );
my $buffer;
my $bytes_read = read( $fh, $buffer, $amount );
return $buffer;
}
}
+
+sub _print_at {
+ my $self = shift;
+ my ($spot, $data) = @_;
+
+ local($/,$\);
+
+ my $fh = $self->_fh;
+ seek( $fh, $spot, SEEK_SET );
+ print( $fh $data );
+
+ return;
+}
+
+sub get_file_version {
+ my $self = shift;
+
+ local($/,$\);
+
+ my $fh = $self->_fh;
+
+ seek( $fh, 13 + $self->_fileobj->{file_offset}, SEEK_SET );
+ my $buffer;
+ my $bytes_read = read( $fh, $buffer, 4 );
+ unless ( $bytes_read == 4 ) {
+ $self->_throw_error( "Cannot read file version" );
+ }
+
+ return unpack( 'N', $buffer );
+}
+
+sub write_file_version {
+ my $self = shift;
+ my ($new_version) = @_;
+
+ local($/,$\);
+
+ my $fh = $self->_fh;
+
+ seek( $fh, 13 + $self->_fileobj->{file_offset}, SEEK_SET );
+ print( $fh pack( 'N', $new_version ) );
+
+ return;
+}
+
projects / dbsrgits/DBM-Deep.git / blobdiff