Edit File: Bzip2.pm
package IO::Compress::Bzip2 ; use strict ; use warnings; use bytes; require Exporter ; use IO::Compress::Base 2.061 ; use IO::Compress::Base::Common 2.061 qw(); use IO::Compress::Adapter::Bzip2 2.061 ; our ($VERSION, @ISA, @EXPORT_OK, %EXPORT_TAGS, $Bzip2Error); $VERSION = '2.061'; $Bzip2Error = ''; @ISA = qw(Exporter IO::Compress::Base); @EXPORT_OK = qw( $Bzip2Error bzip2 ) ; %EXPORT_TAGS = %IO::Compress::Base::EXPORT_TAGS ; push @{ $EXPORT_TAGS{all} }, @EXPORT_OK ; Exporter::export_ok_tags('all'); sub new { my $class = shift ; my $obj = IO::Compress::Base::Common::createSelfTiedObject($class, \$Bzip2Error); return $obj->_create(undef, @_); } sub bzip2 { my $obj = IO::Compress::Base::Common::createSelfTiedObject(undef, \$Bzip2Error); $obj->_def(@_); } sub mkHeader { my $self = shift ; return ''; } sub getExtraParams { my $self = shift ; use IO::Compress::Base::Common 2.061 qw(:Parse); return ( 'blocksize100k' => [IO::Compress::Base::Common::Parse_unsigned, 1], 'workfactor' => [IO::Compress::Base::Common::Parse_unsigned, 0], 'verbosity' => [IO::Compress::Base::Common::Parse_boolean, 0], ); } sub ckParams { my $self = shift ; my $got = shift; # check that BlockSize100K is a number between 1 & 9 if ($got->parsed('blocksize100k')) { my $value = $got->getValue('blocksize100k'); return $self->saveErrorString(undef, "Parameter 'BlockSize100K' not between 1 and 9, got $value") unless defined $value && $value >= 1 && $value <= 9; } # check that WorkFactor between 0 & 250 if ($got->parsed('workfactor')) { my $value = $got->getValue('workfactor'); return $self->saveErrorString(undef, "Parameter 'WorkFactor' not between 0 and 250, got $value") unless $value >= 0 && $value <= 250; } return 1 ; } sub mkComp { my $self = shift ; my $got = shift ; my $BlockSize100K = $got->getValue('blocksize100k'); my $WorkFactor = $got->getValue('workfactor'); my $Verbosity = $got->getValue('verbosity'); my ($obj, $errstr, $errno) = IO::Compress::Adapter::Bzip2::mkCompObject( $BlockSize100K, $WorkFactor, $Verbosity); return $self->saveErrorString(undef, $errstr, $errno) if ! defined $obj; return $obj; } sub mkTrailer { my $self = shift ; return ''; } sub mkFinalTrailer { return ''; } #sub newHeader #{ # my $self = shift ; # return ''; #} sub getInverseClass { return ('IO::Uncompress::Bunzip2'); } sub getFileInfo { my $self = shift ; my $params = shift; my $file = shift ; } 1; __END__ =head1 NAME IO::Compress::Bzip2 - Write bzip2 files/buffers =head1 SYNOPSIS use IO::Compress::Bzip2 qw(bzip2 $Bzip2Error) ; my $status = bzip2 $input => $output [,OPTS] or die "bzip2 failed: $Bzip2Error\n"; my $z = new IO::Compress::Bzip2 $output [,OPTS] or die "bzip2 failed: $Bzip2Error\n"; $z->print($string); $z->printf($format, $string); $z->write($string); $z->syswrite($string [, $length, $offset]); $z->flush(); $z->tell(); $z->eof(); $z->seek($position, $whence); $z->binmode(); $z->fileno(); $z->opened(); $z->autoflush(); $z->input_line_number(); $z->newStream( [OPTS] ); $z->close() ; $Bzip2Error ; # IO::File mode print $z $string; printf $z $format, $string; tell $z eof $z seek $z, $position, $whence binmode $z fileno $z close $z ; =head1 DESCRIPTION This module provides a Perl interface that allows writing bzip2 compressed data to files or buffer. For reading bzip2 files/buffers, see the companion module L<IO::Uncompress::Bunzip2|IO::Uncompress::Bunzip2>. =head1 Functional Interface A top-level function, C<bzip2>, is provided to carry out "one-shot" compression between buffers and/or files. For finer control over the compression process, see the L</"OO Interface"> section. use IO::Compress::Bzip2 qw(bzip2 $Bzip2Error) ; bzip2 $input => $output [,OPTS] or die "bzip2 failed: $Bzip2Error\n"; The functional interface needs Perl5.005 or better. =head2 bzip2 $input => $output [, OPTS] C<bzip2> expects at least two parameters, C<$input> and C<$output>. =head3 The C<$input> parameter The parameter, C<$input>, is used to define the source of the uncompressed data. It can take one of the following forms: =over 5 =item A filename If the C<$input> parameter is a simple scalar, it is assumed to be a filename. This file will be opened for reading and the input data will be read from it. =item A filehandle If the C<$input> parameter is a filehandle, the input data will be read from it. The string '-' can be used as an alias for standard input. =item A scalar reference If C<$input> is a scalar reference, the input data will be read from C<$$input>. =item An array reference If C<$input> is an array reference, each element in the array must be a filename. The input data will be read from each file in turn. The complete array will be walked to ensure that it only contains valid filenames before any data is compressed. =item An Input FileGlob string If C<$input> is a string that is delimited by the characters "<" and ">" C<bzip2> will assume that it is an I<input fileglob string>. The input is the list of files that match the fileglob. If the fileglob does not match any files ... See L<File::GlobMapper|File::GlobMapper> for more details. =back If the C<$input> parameter is any other type, C<undef> will be returned. =head3 The C<$output> parameter The parameter C<$output> is used to control the destination of the compressed data. This parameter can take one of these forms. =over 5 =item A filename If the C<$output> parameter is a simple scalar, it is assumed to be a filename. This file will be opened for writing and the compressed data will be written to it. =item A filehandle If the C<$output> parameter is a filehandle, the compressed data will be written to it. The string '-' can be used as an alias for standard output. =item A scalar reference If C<$output> is a scalar reference, the compressed data will be stored in C<$$output>. =item An Array Reference If C<$output> is an array reference, the compressed data will be pushed onto the array. =item An Output FileGlob If C<$output> is a string that is delimited by the characters "<" and ">" C<bzip2> will assume that it is an I<output fileglob string>. The output is the list of files that match the fileglob. When C<$output> is an fileglob string, C<$input> must also be a fileglob string. Anything else is an error. =back If the C<$output> parameter is any other type, C<undef> will be returned. =head2 Notes When C<$input> maps to multiple files/buffers and C<$output> is a single file/buffer the input files/buffers will be stored in C<$output> as a concatenated series of compressed data streams. =head2 Optional Parameters Unless specified below, the optional parameters for C<bzip2>, C<OPTS>, are the same as those used with the OO interface defined in the L</"Constructor Options"> section below. =over 5 =item C<< AutoClose => 0|1 >> This option applies to any input or output data streams to C<bzip2> that are filehandles. If C<AutoClose> is specified, and the value is true, it will result in all input and/or output filehandles being closed once C<bzip2> has completed. This parameter defaults to 0. =item C<< BinModeIn => 0|1 >> When reading from a file or filehandle, set C<binmode> before reading. Defaults to 0. =item C<< Append => 0|1 >> TODO =back =head2 Examples To read the contents of the file C<file1.txt> and write the compressed data to the file C<file1.txt.bz2>. use strict ; use warnings ; use IO::Compress::Bzip2 qw(bzip2 $Bzip2Error) ; my $input = "file1.txt"; bzip2 $input => "$input.bz2" or die "bzip2 failed: $Bzip2Error\n"; To read from an existing Perl filehandle, C<$input>, and write the compressed data to a buffer, C<$buffer>. use strict ; use warnings ; use IO::Compress::Bzip2 qw(bzip2 $Bzip2Error) ; use IO::File ; my $input = new IO::File "<file1.txt" or die "Cannot open 'file1.txt': $!\n" ; my $buffer ; bzip2 $input => \$buffer or die "bzip2 failed: $Bzip2Error\n"; To compress all files in the directory "/my/home" that match "*.txt" and store the compressed data in the same directory use strict ; use warnings ; use IO::Compress::Bzip2 qw(bzip2 $Bzip2Error) ; bzip2 '</my/home/*.txt>' => '<*.bz2>' or die "bzip2 failed: $Bzip2Error\n"; and if you want to compress each file one at a time, this will do the trick use strict ; use warnings ; use IO::Compress::Bzip2 qw(bzip2 $Bzip2Error) ; for my $input ( glob "/my/home/*.txt" ) { my $output = "$input.bz2" ; bzip2 $input => $output or die "Error compressing '$input': $Bzip2Error\n"; } =head1 OO Interface =head2 Constructor The format of the constructor for C<IO::Compress::Bzip2> is shown below my $z = new IO::Compress::Bzip2 $output [,OPTS] or die "IO::Compress::Bzip2 failed: $Bzip2Error\n"; It returns an C<IO::Compress::Bzip2> object on success and undef on failure. The variable C<$Bzip2Error> will contain an error message on failure. If you are running Perl 5.005 or better the object, C<$z>, returned from IO::Compress::Bzip2 can be used exactly like an L<IO::File|IO::File> filehandle. This means that all normal output file operations can be carried out with C<$z>. For example, to write to a compressed file/buffer you can use either of these forms $z->print("hello world\n"); print $z "hello world\n"; The mandatory parameter C<$output> is used to control the destination of the compressed data. This parameter can take one of these forms. =over 5 =item A filename If the C<$output> parameter is a simple scalar, it is assumed to be a filename. This file will be opened for writing and the compressed data will be written to it. =item A filehandle If the C<$output> parameter is a filehandle, the compressed data will be written to it. The string '-' can be used as an alias for standard output. =item A scalar reference If C<$output> is a scalar reference, the compressed data will be stored in C<$$output>. =back If the C<$output> parameter is any other type, C<IO::Compress::Bzip2>::new will return undef. =head2 Constructor Options C<OPTS> is any combination of the following options: =over 5 =item C<< AutoClose => 0|1 >> This option is only valid when the C<$output> parameter is a filehandle. If specified, and the value is true, it will result in the C<$output> being closed once either the C<close> method is called or the C<IO::Compress::Bzip2> object is destroyed. This parameter defaults to 0. =item C<< Append => 0|1 >> Opens C<$output> in append mode. The behaviour of this option is dependent on the type of C<$output>. =over 5 =item * A Buffer If C<$output> is a buffer and C<Append> is enabled, all compressed data will be append to the end if C<$output>. Otherwise C<$output> will be cleared before any data is written to it. =item * A Filename If C<$output> is a filename and C<Append> is enabled, the file will be opened in append mode. Otherwise the contents of the file, if any, will be truncated before any compressed data is written to it. =item * A Filehandle If C<$output> is a filehandle, the file pointer will be positioned to the end of the file via a call to C<seek> before any compressed data is written to it. Otherwise the file pointer will not be moved. =back This parameter defaults to 0. =item C<< BlockSize100K => number >> Specify the number of 100K blocks bzip2 uses during compression. Valid values are from 1 to 9, where 9 is best compression. The default is 1. =item C<< WorkFactor => number >> Specifies how much effort bzip2 should take before resorting to a slower fallback compression algorithm. Valid values range from 0 to 250, where 0 means use the default value 30. The default is 0. =item C<< Strict => 0|1 >> This is a placeholder option. =back =head2 Examples TODO =head1 Methods =head2 print Usage is $z->print($data) print $z $data Compresses and outputs the contents of the C<$data> parameter. This has the same behaviour as the C<print> built-in. Returns true if successful. =head2 printf Usage is $z->printf($format, $data) printf $z $format, $data Compresses and outputs the contents of the C<$data> parameter. Returns true if successful. =head2 syswrite Usage is $z->syswrite $data $z->syswrite $data, $length $z->syswrite $data, $length, $offset Compresses and outputs the contents of the C<$data> parameter. Returns the number of uncompressed bytes written, or C<undef> if unsuccessful. =head2 write Usage is $z->write $data $z->write $data, $length $z->write $data, $length, $offset Compresses and outputs the contents of the C<$data> parameter. Returns the number of uncompressed bytes written, or C<undef> if unsuccessful. =head2 flush Usage is $z->flush; Flushes any pending compressed data to the output file/buffer. TODO Returns true on success. =head2 tell Usage is $z->tell() tell $z Returns the uncompressed file offset. =head2 eof Usage is $z->eof(); eof($z); Returns true if the C<close> method has been called. =head2 seek $z->seek($position, $whence); seek($z, $position, $whence); Provides a sub-set of the C<seek> functionality, with the restriction that it is only legal to seek forward in the output file/buffer. It is a fatal error to attempt to seek backward. Empty parts of the file/buffer will have NULL (0x00) bytes written to them. The C<$whence> parameter takes one the usual values, namely SEEK_SET, SEEK_CUR or SEEK_END. Returns 1 on success, 0 on failure. =head2 binmode Usage is $z->binmode binmode $z ; This is a noop provided for completeness. =head2 opened $z->opened() Returns true if the object currently refers to a opened file/buffer. =head2 autoflush my $prev = $z->autoflush() my $prev = $z->autoflush(EXPR) If the C<$z> object is associated with a file or a filehandle, this method returns the current autoflush setting for the underlying filehandle. If C<EXPR> is present, and is non-zero, it will enable flushing after every write/print operation. If C<$z> is associated with a buffer, this method has no effect and always returns C<undef>. B<Note> that the special variable C<$|> B<cannot> be used to set or retrieve the autoflush setting. =head2 input_line_number $z->input_line_number() $z->input_line_number(EXPR) This method always returns C<undef> when compressing. =head2 fileno $z->fileno() fileno($z) If the C<$z> object is associated with a file or a filehandle, C<fileno> will return the underlying file descriptor. Once the C<close> method is called C<fileno> will return C<undef>. If the C<$z> object is is associated with a buffer, this method will return C<undef>. =head2 close $z->close() ; close $z ; Flushes any pending compressed data and then closes the output file/buffer. For most versions of Perl this method will be automatically invoked if the IO::Compress::Bzip2 object is destroyed (either explicitly or by the variable with the reference to the object going out of scope). The exceptions are Perl versions 5.005 through 5.00504 and 5.8.0. In these cases, the C<close> method will be called automatically, but not until global destruction of all live objects when the program is terminating. Therefore, if you want your scripts to be able to run on all versions of Perl, you should call C<close> explicitly and not rely on automatic closing. Returns true on success, otherwise 0. If the C<AutoClose> option has been enabled when the IO::Compress::Bzip2 object was created, and the object is associated with a file, the underlying file will also be closed. =head2 newStream([OPTS]) Usage is $z->newStream( [OPTS] ) Closes the current compressed data stream and starts a new one. OPTS consists of any of the the options that are available when creating the C<$z> object. See the L</"Constructor Options"> section for more details. =head1 Importing No symbolic constants are required by this IO::Compress::Bzip2 at present. =over 5 =item :all Imports C<bzip2> and C<$Bzip2Error>. Same as doing this use IO::Compress::Bzip2 qw(bzip2 $Bzip2Error) ; =back =head1 EXAMPLES =head2 Apache::GZip Revisited See L<IO::Compress::Bzip2::FAQ|IO::Compress::Bzip2::FAQ/"Apache::GZip Revisited"> =head2 Working with Net::FTP See L<IO::Compress::Bzip2::FAQ|IO::Compress::Bzip2::FAQ/"Compressed files and Net::FTP"> =head1 SEE ALSO L<Compress::Zlib>, L<IO::Compress::Gzip>, L<IO::Uncompress::Gunzip>, L<IO::Compress::Deflate>, L<IO::Uncompress::Inflate>, L<IO::Compress::RawDeflate>, L<IO::Uncompress::RawInflate>, L<IO::Uncompress::Bunzip2>, L<IO::Compress::Lzop>, L<IO::Uncompress::UnLzop>, L<IO::Compress::Lzf>, L<IO::Uncompress::UnLzf>, L<IO::Uncompress::AnyInflate>, L<IO::Uncompress::AnyUncompress> L<Compress::Zlib::FAQ|Compress::Zlib::FAQ> L<File::GlobMapper|File::GlobMapper>, L<Archive::Zip|Archive::Zip>, L<Archive::Tar|Archive::Tar>, L<IO::Zlib|IO::Zlib> The primary site for the bzip2 program is F<http://www.bzip.org>. See the module L<Compress::Bzip2|Compress::Bzip2> =head1 AUTHOR This module was written by Paul Marquess, F<pmqs@cpan.org>. =head1 MODIFICATION HISTORY See the Changes file. =head1 COPYRIGHT AND LICENSE Copyright (c) 2005-2008 Paul Marquess. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.