NAME Bitmask::Data - Handle bitmasks in an easy and flexible way SYNOPSIS # Create a simple bitmask class packacke MyBitmask; use base qw(Bitmask::Data); __PACKAGE__->bitmask_length(18); __PACKAGE__->bitmask_default(0b000000000000000011); __PACKAGE__->init( 'value1' => 0b000000000000000001, 'value2' => 0b000000000000000010, 'value2' => 0b000000000000000100, 'value4' => 0b000000000000001000, 'value5' => 0b000000000000010000, ... ); ## Somewhere else in your code use MyBitmask; my $bm = MyBitmask->new('value1','value3'); $bm->mask; DESCRIPTION This package helps you dealing with bitmasks. First you need to subclass Bitmask::Data and set the bitmask values and length. (If you are only working with a single bitmask in a simple application you might also initialize the bitmask directly in the Bitmask::Data module). After the initialization you can create an arbitrary number of bitmask objects which can be accessed and manipulated with convenient methods. METHODS Class Methods bitmask_length Set/Get the length of the bitmask. Changing this value after the initialization is not recommended. Default: 16 bitmask_default Set/Get the default bitmask for empty Bitmask::Data objects. Default: undef bitmask_complex Boolean value that enables/disables checks for composed bitmasks. If false init will only accept bitmask bit values that are powers of 2. Default: 0 Complex bitmask also allow the creation of overlapping bitmask values: packacke LocaleBitmask; use base qw(Bitmask::Data); __PACKAGE__->bitmask_length(8); # 8 bits __PACKAGE__->bitmask_complex(1); # enable overlapping bitmasks __PACKAGE__->init( AT => 0b000_00001, # Austria CH => 0b000_00010, # Switzerland DE => 0b000_00100, # Germany FR => 0b000_01000, # France IT => 0b000_10000, # Italy de => 0b001_00000, # German fr => 0b010_00000, # French it => 0b100_00000, # Italian de_AT => 0b001_00001, # German / Austria de_CH => 0b001_00010, # German / Switzerland de_DE => 0b001_00100, # German / Germany fr_CH => 0b010_00010, # French / Germany fr_FR => 0b010_01000, # French / France it_CH => 0b100_00010, # Italian / Germany it_IT => 0b100_10000, # Italian / Italy ); # Somewhere else LocaleBitmask->new('de')->hasany('de'); # true LocaleBitmask->new('de')->hasany('de_DE'); # true LocaleBitmask->new('de')->hasall('de_DE'); # false LocaleBitmask->new('de_DE','de_AT','de_CH')->hasexact('de','AT','DE','CH'); # true LocaleBitmask->new('de_DE','de_AT','de_CH')->list # de,DE,de_DE,de_AT,AT,de_CH,CH bitmask_lazyinit Boolean value that enables/disables warnings for lazy initialization. ( Lazy initialization = call of init without bitmask bit values) Default: 0 bitmask_items HASHREF of all bitmask items. Don't mess around here unless you know what you are doing. init CLASS->init(LIST of VALUES); Initializes the bitmask class. You can supply a list of possible values. Optionally you can also specify the bits for the mask by adding bit values after the value. CLASS->init( 'value1' => 0b000001, 'value2' => 0b000010, 'value3' => 0b001000, 'value4' => 0b010000, ); With "bitmask_lazyinit" enabled you can also skip the bitmask bit values CLASS->bitmask_lazyinit(1); CLASS->init( 'value1', 'value2', 'value3', 'value4', ); data2bit CLASS->data2bit(VALUE); Returns the corresponding bit for the given value. bit2data CLASS->bit2data(BIT); Returns the corresponding value for the given bit. bm2data CLASS->bm2data(BITMASK); Returns all the value for the given bitmask. any2data CLASS->any2data(124); # Bitmask CLASS->any2data('de_DE'); # Value CLASS->any2data(0b110001001); # Bitmask in bit notation CLASS->any2data('0B110001001'); # Bitmask string CLASS->any2data('0b111000001'); # Bitmask string Turns a single value (bit, bitmask,value, bitmask string) into a value. _parse_params CLASS->_parse_params(LIST) Helper method for parsing params passed to various methods. Public Methods new my $bm = MyBitmask->new(); my $bm = MyBitmask->new('value1'); my $bm = MyBitmask->new('value2', 'value3'); my $bm = MyBitmask->new('0b00010000010000'); my $bm = MyBitmask->new(124); my $bm = MyBitmask->new(0b00010000010000); my $bm = MyBitmask->new(0x2); my $bm = MyBitmask->new([32, 'value1', 0b00010000010000]); Create a new bitmask object. You can supply almost any combination of bits, bitmasks and values, even mix different types. * LIST or ARRAYREF of values * LIST or ARRAYREF of strings representing bits or bitmasks (starting with '0b') * LIST or ARRAYREF of bitmasks * Any combination of the above clone $bm2 = $bm->clone(); Clones a bitmask object set $bm->set(ITEMS); This method takes the same arguments as "new". It resets the current bitmask and sets the supplied arguments. Returns the object. list $bm->list() In list context, this returns a list of the set values in scalar context, this returns an array reference to the list of values. length $bm->length() Number of set bitmask values. first $bm->first() Returns the first set value (the order of the values is determied by the sequence of the addition) remove $bm->remove(ITEMS); This method takes the same arguments as "new". The values supplied in the arguments will be unset. Returns the object. reset $bm->reset(); Unsets all values, leaving an empty list. Returns the object. setall $bm->setall(); Sets all values. Returns the object. add $bm->add(ITEMS); This method takes the same arguments as "new". The specified values will be set. Returns the object. mask $bm->mask(); Returns the integer representing the bitmask of all the set values. string $bm->string(); Retuns the string representing the bitmask. sqlfilter_all $bm->sqlfilter_all($field); This method can be used for database searches in conjunction with SQL::Abstract an POSTGRESQL (SQL::Abstract is used by "DBIx::Class" for generating searches). The search will find all database rows with bitmask that have at least the given values set. (use the "sql" method for an exact match) Example how to use sqlfilter with SQL::Abstract: my($stmt, @bind) = $sql->select( 'mytable', \@fields, { $bm->sqlfilter_all('mytable.bitmaskfield'), } ); Example how to use sqlfilter with DBIx::Class: my $list = $resultset->search( { $bm->sqlfilter_all('me.bitmaskfield'), }, ); sqlfilter Shortcut for "sqlfilter_all" sqlfilter_any $bm->sqlfilter_any($field); Works like "sqlfilter_all" but checks for any bit matching hasall $bm->hasall(ITEMS); This method takes the same arguments as "new". Checks if all requestes items are set and returns true or false. hasexact $bm->hasexact(ITEMS); This method takes the same arguments as "new". Checks if the requestes items exactly match the set values. hasany $bm->hasany(ITEMS); This method takes the same arguments as "new". Checks if at least one set value matches the supplied value list and returns true or false CAVEATS Since Bitmask::Data is very liberal with input data you cannot use numbers as bitmask values. Bitmask::Data also adds a considerable processing overhead (especially when the bitmask_complex option is enabled) to bitmask manipulations. SUBCLASSING Bitmask::Data was designed to be subclassed. package MyBitmask; use base qw(Bitmask::Data); __PACKAGE__->bitmask_length(20); # Default length is 16 __PACKAGE__->init( 'value1' => 0b000000000000000001, 'value2' => 0x2, 'value2' => 4, 'value4', # lazy initlialization 'value5', # lazy initlialization ); WORKING WITH DATABASES This module comes with support for POSTGRESQL databases (patches for other database vendors are welcome). First you need to create the correct column types: CREATE TABLE bitmaskexample ( id integer DEFAULT nextval('pkey_seq'::regclass) NOT NULL, bitmask bit(14), otherfields character varying ); The length of the bitmask field must match "CLASS->bitmask_length". This module provides three convenient methods to work with databases: * sqlfilter_all: Search for matching bitmasks * sqlfilter_any: Search for bitmasks with matching bits * string: Print the bitmask string as used by postgres database If you are working with DBIx::Class you might also install de- and inflators for Bitmask objects: __PACKAGE__->inflate_column('fieldname',{ inflate => sub { my $value = shift; return MyBitmask->new($value); }, deflate => sub { my $value = shift; undef $value unless ref($value) && $value->isa('MyBitmask'); $value //= MyBitmask->new(); return $value->string; }, }); SUPPORT Please report any bugs or feature requests to "bug-bitmask-data@rt.cpan.org", or through the web interface at . I will be notified and then you'll automatically be notified of the progress on your report as I make changes. AUTHOR Klaus Ita koki [at] worstofall.com Maroš Kollár CPAN ID: MAROS maros [at] k-1.com L ACKNOWLEDGEMENTS This module was originally written by Klaus Ita (Koki) for Revdev , a nice litte software company I (Maros) run with Koki and Domm (). COPYRIGHT Bitmask::Data is Copyright (c) 2008 Klaus Ita, Maroš Kollár - This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. The full text of the license can be found in the LICENSE file included with this module.