package Number::Phone::UK::DBM::Deep::Array;
use strict;
# This is to allow Number::Phone::UK::DBM::Deep::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.
use vars qw( $NEGATIVE_INDICES );
$NEGATIVE_INDICES = 1;
use base 'Number::Phone::UK::DBM::Deep';
use Scalar::Util ();
sub _get_self {
eval { local $SIG{'__DIE__'}; tied( @{$_[0]} ) } || $_[0]
}
sub TIEARRAY {
##
# Tied array constructor method, called by Perl's tie() function.
##
my $class = shift;
my $args = $class->_get_args( @_ );
$args->{type} = $class->TYPE_ARRAY;
return $class->_init($args);
}
sub FETCH {
my $self = $_[0]->_get_self;
my $key = $_[1];
$self->lock( $self->LOCK_SH );
if ( $key =~ /^-?\d+$/ ) {
if ( $key < 0 ) {
$key += $self->FETCHSIZE;
unless ( $key >= 0 ) {
$self->unlock;
return;
}
}
$key = pack($Number::Phone::UK::DBM::Deep::LONG_PACK, $key);
}
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 $orig = $key;
my $size;
my $numeric_idx;
if ( $key =~ /^\-?\d+$/ ) {
$numeric_idx = 1;
if ( $key < 0 ) {
$size = $self->FETCHSIZE;
$key += $size;
if ( $key < 0 ) {
die( "Modification of non-creatable array value attempted, subscript $orig" );
}
}
$key = pack($Number::Phone::UK::DBM::Deep::LONG_PACK, $key);
}
my $rv = $self->SUPER::STORE( $key, $value );
if ( $numeric_idx && $rv == 2 ) {
$size = $self->FETCHSIZE unless defined $size;
if ( $orig >= $size ) {
$self->STORESIZE( $orig + 1 );
}
}
$self->unlock;
return $rv;
}
sub EXISTS {
my $self = $_[0]->_get_self;
my $key = $_[1];
$self->lock( $self->LOCK_SH );
if ( $key =~ /^\-?\d+$/ ) {
if ( $key < 0 ) {
$key += $self->FETCHSIZE;
unless ( $key >= 0 ) {
$self->unlock;
return;
}
}
$key = pack($Number::Phone::UK::DBM::Deep::LONG_PACK, $key);
}
my $rv = $self->SUPER::EXISTS( $key );
$self->unlock;
return $rv;
}
sub DELETE {
my $self = $_[0]->_get_self;
my $key = $_[1];
my $unpacked_key = $key;
$self->lock( $self->LOCK_EX );
my $size = $self->FETCHSIZE;
if ( $key =~ /^-?\d+$/ ) {
if ( $key < 0 ) {
$key += $size;
unless ( $key >= 0 ) {
$self->unlock;
return;
}
}
$key = pack($Number::Phone::UK::DBM::Deep::LONG_PACK, $key);
}
my $rv = $self->SUPER::DELETE( $key );
if ($rv && $unpacked_key == $size - 1) {
$self->STORESIZE( $unpacked_key );
}
$self->unlock;
return $rv;
}
sub FETCHSIZE {
##
# Return the length of the array
##
my $self = shift->_get_self;
$self->lock( $self->LOCK_SH );
my $SAVE_FILTER = $self->_root->{filter_fetch_value};
$self->_root->{filter_fetch_value} = undef;
my $packed_size = $self->FETCH('length');
$self->_root->{filter_fetch_value} = $SAVE_FILTER;
$self->unlock;
if ($packed_size) {
return int(unpack($Number::Phone::UK::DBM::Deep::LONG_PACK, $packed_size));
}
return 0;
}
sub STORESIZE {
##
# Set the length of the array
##
my $self = $_[0]->_get_self;
my $new_length = $_[1];
$self->lock( $self->LOCK_EX );
my $SAVE_FILTER = $self->_root->{filter_store_value};
$self->_root->{filter_store_value} = undef;
my $result = $self->STORE('length', pack($Number::Phone::UK::DBM::Deep::LONG_PACK, $new_length));
$self->_root->{filter_store_value} = $SAVE_FILTER;
$self->unlock;
return $result;
}
sub POP {
##
# Remove and return the last element on the array
##
my $self = $_[0]->_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 {
##
# Add new element(s) to the end of the array
##
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;
}
sub SHIFT {
##
# Remove and return first element on the array.
# Shift over remaining elements to take up space.
##
my $self = $_[0]->_get_self;
$self->lock( $self->LOCK_EX );
my $length = $self->FETCHSIZE();
if ($length) {
my $content = $self->FETCH( 0 );
##
# Shift elements over and remove last one.
##
for (my $i = 0; $i < $length - 1; $i++) {
$self->STORE( $i, $self->FETCH($i + 1) );
}
$self->DELETE( $length - 1 );
$self->unlock;
return $content;
}
else {
$self->unlock;
return;
}
}
sub UNSHIFT {
##
# Insert new element(s) at beginning of array.
# Shift over other elements to make space.
##
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->STORE( $i + $new_size, $self->FETCH($i) );
}
}
for (my $i = 0; $i < $new_size; $i++) {
$self->STORE( $i, $new_elements[$i] );
}
$self->unlock;
return $length + $new_size;
}
sub SPLICE {
##
# Splices section of array with optional new section.
# Returns deleted section, or last element deleted in scalar context.
##
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->STORE( $i + ($new_size - $splice_length), $self->FETCH($i) );
}
}
else {
for (my $i = $offset + $splice_length; $i < $length; $i++) {
$self->STORE( $i + ($new_size - $splice_length), $self->FETCH($i) );
}
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];
}
sub EXTEND {
##
# Perl will call EXTEND() when the array is likely to grow.
# We don't care, but include it for compatibility.
##
}
##
# Public method aliases
##
*length = *FETCHSIZE;
*pop = *POP;
*push = *PUSH;
*shift = *SHIFT;
*unshift = *UNSHIFT;
*splice = *SPLICE;
1;
__END__