1 package IO::Compress::RawDeflate ;
10 use IO::Compress::Base 2.010 ;
11 use IO::Compress::Base::Common 2.010 qw(:Status createSelfTiedObject);
12 use IO::Compress::Adapter::Deflate 2.010 ;
17 our ($VERSION, @ISA, @EXPORT_OK, %DEFLATE_CONSTANTS, %EXPORT_TAGS, $RawDeflateError);
20 $RawDeflateError = '';
22 @ISA = qw(Exporter IO::Compress::Base);
23 @EXPORT_OK = qw( $RawDeflateError rawdeflate ) ;
25 %EXPORT_TAGS = ( flush => [qw{
51 foreach (keys %EXPORT_TAGS )
53 push @{$EXPORT_TAGS{constants}},
57 $EXPORT_TAGS{all} = $EXPORT_TAGS{constants} ;
61 %DEFLATE_CONSTANTS = %EXPORT_TAGS;
63 push @{ $EXPORT_TAGS{all} }, @EXPORT_OK ;
65 Exporter::export_ok_tags('all');
73 my $obj = createSelfTiedObject($class, \$RawDeflateError);
75 return $obj->_create(undef, @_);
80 my $obj = createSelfTiedObject(undef, \$RawDeflateError);
81 return $obj->_def(@_);
98 my ($obj, $errstr, $errno) = IO::Compress::Adapter::Deflate::mkCompObject(
100 $got->value('Adler32'),
101 $got->value('Level'),
102 $got->value('Strategy')
105 return $self->saveErrorString(undef, $errstr, $errno)
139 return $self->getZlibParams();
146 use IO::Compress::Base::Common 2.010 qw(:Parse);
147 use Compress::Raw::Zlib 2.010 qw(Z_DEFLATED Z_DEFAULT_COMPRESSION Z_DEFAULT_STRATEGY);
153 #'Method' => [0, 1, Parse_unsigned, Z_DEFLATED],
154 'Level' => [0, 1, Parse_signed, Z_DEFAULT_COMPRESSION],
155 'Strategy' => [0, 1, Parse_signed, Z_DEFAULT_STRATEGY],
157 'CRC32' => [0, 1, Parse_boolean, 0],
158 'ADLER32' => [0, 1, Parse_boolean, 0],
159 'Merge' => [1, 1, Parse_boolean, 0],
167 return ('IO::Uncompress::RawInflate',
168 \$IO::Uncompress::RawInflate::RawInflateError);
179 use IO::Seekable qw(SEEK_SET);
184 my $outValue = shift ;
185 my $outType = shift ;
187 my ($invClass, $error_ref) = $self->getInverseClass();
188 eval "require $invClass"
191 my $inf = $invClass->new( $outValue,
196 or return $self->saveErrorString(undef, "Cannot create InflateScan object: $$error_ref" ) ;
200 or return $self->saveErrorString(undef, "Error Scanning: $$error_ref", $inf->errorNo) ;
201 $inf->zap($end_offset)
202 or return $self->saveErrorString(undef, "Error Zapping: $$error_ref", $inf->errorNo) ;
204 my $def = *$self->{Compress} = $inf->createDeflate();
206 *$self->{Header} = *$inf->{Info}{Header};
207 *$self->{UnCompSize} = *$inf->{UnCompSize}->clone();
208 *$self->{CompSize} = *$inf->{CompSize}->clone();
210 #*$self->{CompSize} = new U64(0, *$self->{UnCompSize_32bit});
213 if ( $outType eq 'buffer')
214 { substr( ${ *$self->{Buffer} }, $end_offset) = '' }
215 elsif ($outType eq 'handle' || $outType eq 'filename') {
216 *$self->{FH} = *$inf->{FH} ;
218 *$self->{FH}->flush() ;
219 *$self->{Handle} = 1 if $outType eq 'handle';
221 #seek(*$self->{FH}, $end_offset, SEEK_SET)
222 *$self->{FH}->seek($end_offset, SEEK_SET)
223 or return $self->saveErrorString(undef, $!, $!) ;
229 #### zlib specific methods
236 my $strategy = shift ;
238 my $status = *$self->{Compress}->deflateParams(Level => $level, Strategy => $strategy) ;
239 return $self->saveErrorString(0, *$self->{Compress}{Error}, *$self->{Compress}{ErrorNo})
240 if $status == STATUS_ERROR;
254 IO::Compress::RawDeflate - Write RFC 1951 files/buffers
260 use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ;
262 my $status = rawdeflate $input => $output [,OPTS]
263 or die "rawdeflate failed: $RawDeflateError\n";
265 my $z = new IO::Compress::RawDeflate $output [,OPTS]
266 or die "rawdeflate failed: $RawDeflateError\n";
269 $z->printf($format, $string);
271 $z->syswrite($string [, $length, $offset]);
275 $z->seek($position, $whence);
280 $z->input_line_number();
281 $z->newStream( [OPTS] );
292 printf $z $format, $string;
295 seek $z, $position, $whence
303 This module provides a Perl interface that allows writing compressed
304 data to files or buffer as defined in RFC 1951.
306 Note that RFC 1951 data is not a good choice of compression format
307 to use in isolation, especially if you want to auto-detect it.
309 For reading RFC 1951 files/buffers, see the companion module
310 L<IO::Uncompress::RawInflate|IO::Uncompress::RawInflate>.
312 =head1 Functional Interface
314 A top-level function, C<rawdeflate>, is provided to carry out
315 "one-shot" compression between buffers and/or files. For finer
316 control over the compression process, see the L</"OO Interface">
319 use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ;
321 rawdeflate $input => $output [,OPTS]
322 or die "rawdeflate failed: $RawDeflateError\n";
324 The functional interface needs Perl5.005 or better.
326 =head2 rawdeflate $input => $output [, OPTS]
328 C<rawdeflate> expects at least two parameters, C<$input> and C<$output>.
330 =head3 The C<$input> parameter
332 The parameter, C<$input>, is used to define the source of
333 the uncompressed data.
335 It can take one of the following forms:
341 If the C<$input> parameter is a simple scalar, it is assumed to be a
342 filename. This file will be opened for reading and the input data
343 will be read from it.
347 If the C<$input> parameter is a filehandle, the input data will be
349 The string '-' can be used as an alias for standard input.
351 =item A scalar reference
353 If C<$input> is a scalar reference, the input data will be read
356 =item An array reference
358 If C<$input> is an array reference, each element in the array must be a
361 The input data will be read from each file in turn.
363 The complete array will be walked to ensure that it only
364 contains valid filenames before any data is compressed.
366 =item An Input FileGlob string
368 If C<$input> is a string that is delimited by the characters "<" and ">"
369 C<rawdeflate> will assume that it is an I<input fileglob string>. The
370 input is the list of files that match the fileglob.
372 If the fileglob does not match any files ...
374 See L<File::GlobMapper|File::GlobMapper> for more details.
378 If the C<$input> parameter is any other type, C<undef> will be returned.
380 =head3 The C<$output> parameter
382 The parameter C<$output> is used to control the destination of the
383 compressed data. This parameter can take one of these forms.
389 If the C<$output> parameter is a simple scalar, it is assumed to be a
390 filename. This file will be opened for writing and the compressed
391 data will be written to it.
395 If the C<$output> parameter is a filehandle, the compressed data
396 will be written to it.
397 The string '-' can be used as an alias for standard output.
399 =item A scalar reference
401 If C<$output> is a scalar reference, the compressed data will be
402 stored in C<$$output>.
404 =item An Array Reference
406 If C<$output> is an array reference, the compressed data will be
407 pushed onto the array.
409 =item An Output FileGlob
411 If C<$output> is a string that is delimited by the characters "<" and ">"
412 C<rawdeflate> will assume that it is an I<output fileglob string>. The
413 output is the list of files that match the fileglob.
415 When C<$output> is an fileglob string, C<$input> must also be a fileglob
416 string. Anything else is an error.
420 If the C<$output> parameter is any other type, C<undef> will be returned.
424 When C<$input> maps to multiple files/buffers and C<$output> is a single
425 file/buffer the input files/buffers will be stored
426 in C<$output> as a concatenated series of compressed data streams.
428 =head2 Optional Parameters
430 Unless specified below, the optional parameters for C<rawdeflate>,
431 C<OPTS>, are the same as those used with the OO interface defined in the
432 L</"Constructor Options"> section below.
436 =item C<< AutoClose => 0|1 >>
438 This option applies to any input or output data streams to
439 C<rawdeflate> that are filehandles.
441 If C<AutoClose> is specified, and the value is true, it will result in all
442 input and/or output filehandles being closed once C<rawdeflate> has
445 This parameter defaults to 0.
447 =item C<< BinModeIn => 0|1 >>
449 When reading from a file or filehandle, set C<binmode> before reading.
453 =item C<< Append => 0|1 >>
461 To read the contents of the file C<file1.txt> and write the compressed
462 data to the file C<file1.txt.1951>.
466 use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ;
468 my $input = "file1.txt";
469 rawdeflate $input => "$input.1951"
470 or die "rawdeflate failed: $RawDeflateError\n";
472 To read from an existing Perl filehandle, C<$input>, and write the
473 compressed data to a buffer, C<$buffer>.
477 use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ;
480 my $input = new IO::File "<file1.txt"
481 or die "Cannot open 'file1.txt': $!\n" ;
483 rawdeflate $input => \$buffer
484 or die "rawdeflate failed: $RawDeflateError\n";
486 To compress all files in the directory "/my/home" that match "*.txt"
487 and store the compressed data in the same directory
491 use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ;
493 rawdeflate '</my/home/*.txt>' => '<*.1951>'
494 or die "rawdeflate failed: $RawDeflateError\n";
496 and if you want to compress each file one at a time, this will do the trick
500 use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ;
502 for my $input ( glob "/my/home/*.txt" )
504 my $output = "$input.1951" ;
505 rawdeflate $input => $output
506 or die "Error compressing '$input': $RawDeflateError\n";
513 The format of the constructor for C<IO::Compress::RawDeflate> is shown below
515 my $z = new IO::Compress::RawDeflate $output [,OPTS]
516 or die "IO::Compress::RawDeflate failed: $RawDeflateError\n";
518 It returns an C<IO::Compress::RawDeflate> object on success and undef on failure.
519 The variable C<$RawDeflateError> will contain an error message on failure.
521 If you are running Perl 5.005 or better the object, C<$z>, returned from
522 IO::Compress::RawDeflate can be used exactly like an L<IO::File|IO::File> filehandle.
523 This means that all normal output file operations can be carried out
525 For example, to write to a compressed file/buffer you can use either of
528 $z->print("hello world\n");
529 print $z "hello world\n";
531 The mandatory parameter C<$output> is used to control the destination
532 of the compressed data. This parameter can take one of these forms.
538 If the C<$output> parameter is a simple scalar, it is assumed to be a
539 filename. This file will be opened for writing and the compressed data
540 will be written to it.
544 If the C<$output> parameter is a filehandle, the compressed data will be
546 The string '-' can be used as an alias for standard output.
548 =item A scalar reference
550 If C<$output> is a scalar reference, the compressed data will be stored
555 If the C<$output> parameter is any other type, C<IO::Compress::RawDeflate>::new will
558 =head2 Constructor Options
560 C<OPTS> is any combination of the following options:
564 =item C<< AutoClose => 0|1 >>
566 This option is only valid when the C<$output> parameter is a filehandle. If
567 specified, and the value is true, it will result in the C<$output> being
568 closed once either the C<close> method is called or the C<IO::Compress::RawDeflate>
571 This parameter defaults to 0.
573 =item C<< Append => 0|1 >>
575 Opens C<$output> in append mode.
577 The behaviour of this option is dependent on the type of C<$output>.
583 If C<$output> is a buffer and C<Append> is enabled, all compressed data
584 will be append to the end if C<$output>. Otherwise C<$output> will be
585 cleared before any data is written to it.
589 If C<$output> is a filename and C<Append> is enabled, the file will be
590 opened in append mode. Otherwise the contents of the file, if any, will be
591 truncated before any compressed data is written to it.
595 If C<$output> is a filehandle, the file pointer will be positioned to the
596 end of the file via a call to C<seek> before any compressed data is written
597 to it. Otherwise the file pointer will not be moved.
601 This parameter defaults to 0.
603 =item C<< Merge => 0|1 >>
605 This option is used to compress input data and append it to an existing
606 compressed data stream in C<$output>. The end result is a single compressed
607 data stream stored in C<$output>.
609 It is a fatal error to attempt to use this option when C<$output> is not an
610 RFC 1951 data stream.
612 There are a number of other limitations with the C<Merge> option:
618 This module needs to have been built with zlib 1.2.1 or better to work. A
619 fatal error will be thrown if C<Merge> is used with an older version of
624 If C<$output> is a file or a filehandle, it must be seekable.
628 This parameter defaults to 0.
632 Defines the compression level used by zlib. The value should either be
633 a number between 0 and 9 (0 means no compression and 9 is maximum
634 compression), or one of the symbolic constants defined below.
639 Z_DEFAULT_COMPRESSION
641 The default is Z_DEFAULT_COMPRESSION.
643 Note, these constants are not imported by C<IO::Compress::RawDeflate> by default.
645 use IO::Compress::RawDeflate qw(:strategy);
646 use IO::Compress::RawDeflate qw(:constants);
647 use IO::Compress::RawDeflate qw(:all);
651 Defines the strategy used to tune the compression. Use one of the symbolic
652 constants defined below.
660 The default is Z_DEFAULT_STRATEGY.
662 =item C<< Strict => 0|1 >>
664 This is a placeholder option.
681 Compresses and outputs the contents of the C<$data> parameter. This
682 has the same behaviour as the C<print> built-in.
684 Returns true if successful.
690 $z->printf($format, $data)
691 printf $z $format, $data
693 Compresses and outputs the contents of the C<$data> parameter.
695 Returns true if successful.
702 $z->syswrite $data, $length
703 $z->syswrite $data, $length, $offset
705 Compresses and outputs the contents of the C<$data> parameter.
707 Returns the number of uncompressed bytes written, or C<undef> if
715 $z->write $data, $length
716 $z->write $data, $length, $offset
718 Compresses and outputs the contents of the C<$data> parameter.
720 Returns the number of uncompressed bytes written, or C<undef> if
728 $z->flush($flush_type);
730 Flushes any pending compressed data to the output file/buffer.
732 This method takes an optional parameter, C<$flush_type>, that controls
733 how the flushing will be carried out. By default the C<$flush_type>
734 used is C<Z_FINISH>. Other valid values for C<$flush_type> are
735 C<Z_NO_FLUSH>, C<Z_SYNC_FLUSH>, C<Z_FULL_FLUSH> and C<Z_BLOCK>. It is
736 strongly recommended that you only set the C<flush_type> parameter if
737 you fully understand the implications of what it does - overuse of C<flush>
738 can seriously degrade the level of compression achieved. See the C<zlib>
739 documentation for details.
741 Returns true on success.
750 Returns the uncompressed file offset.
759 Returns true if the C<close> method has been called.
763 $z->seek($position, $whence);
764 seek($z, $position, $whence);
766 Provides a sub-set of the C<seek> functionality, with the restriction
767 that it is only legal to seek forward in the output file/buffer.
768 It is a fatal error to attempt to seek backward.
770 Empty parts of the file/buffer will have NULL (0x00) bytes written to them.
772 The C<$whence> parameter takes one the usual values, namely SEEK_SET,
773 SEEK_CUR or SEEK_END.
775 Returns 1 on success, 0 on failure.
784 This is a noop provided for completeness.
790 Returns true if the object currently refers to a opened file/buffer.
794 my $prev = $z->autoflush()
795 my $prev = $z->autoflush(EXPR)
797 If the C<$z> object is associated with a file or a filehandle, this method
798 returns the current autoflush setting for the underlying filehandle. If
799 C<EXPR> is present, and is non-zero, it will enable flushing after every
800 write/print operation.
802 If C<$z> is associated with a buffer, this method has no effect and always
805 B<Note> that the special variable C<$|> B<cannot> be used to set or
806 retrieve the autoflush setting.
808 =head2 input_line_number
810 $z->input_line_number()
811 $z->input_line_number(EXPR)
813 This method always returns C<undef> when compressing.
820 If the C<$z> object is associated with a file or a filehandle, C<fileno>
821 will return the underlying file descriptor. Once the C<close> method is
822 called C<fileno> will return C<undef>.
824 If the C<$z> object is is associated with a buffer, this method will return
832 Flushes any pending compressed data and then closes the output file/buffer.
834 For most versions of Perl this method will be automatically invoked if
835 the IO::Compress::RawDeflate object is destroyed (either explicitly or by the
836 variable with the reference to the object going out of scope). The
837 exceptions are Perl versions 5.005 through 5.00504 and 5.8.0. In
838 these cases, the C<close> method will be called automatically, but
839 not until global destruction of all live objects when the program is
842 Therefore, if you want your scripts to be able to run on all versions
843 of Perl, you should call C<close> explicitly and not rely on automatic
846 Returns true on success, otherwise 0.
848 If the C<AutoClose> option has been enabled when the IO::Compress::RawDeflate
849 object was created, and the object is associated with a file, the
850 underlying file will also be closed.
852 =head2 newStream([OPTS])
856 $z->newStream( [OPTS] )
858 Closes the current compressed data stream and starts a new one.
860 OPTS consists of any of the the options that are available when creating
863 See the L</"Constructor Options"> section for more details.
875 A number of symbolic constants are required by some methods in
876 C<IO::Compress::RawDeflate>. None are imported by default.
882 Imports C<rawdeflate>, C<$RawDeflateError> and all symbolic
883 constants that can be used by C<IO::Compress::RawDeflate>. Same as doing this
885 use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError :constants) ;
889 Import all symbolic constants. Same as doing this
891 use IO::Compress::RawDeflate qw(:flush :level :strategy) ;
895 These symbolic constants are used by the C<flush> method.
906 These symbolic constants are used by the C<Level> option in the constructor.
911 Z_DEFAULT_COMPRESSION
915 These symbolic constants are used by the C<Strategy> option in the constructor.
930 =head2 Apache::GZip Revisited
932 See L<IO::Compress::Zlib::FAQ|IO::Compress::Zlib::FAQ/"Apache::GZip Revisited">
936 =head2 Working with Net::FTP
938 See L<IO::Compress::Zlib::FAQ|IO::Compress::Zlib::FAQ/"Compressed files and Net::FTP">
942 L<Compress::Zlib>, L<IO::Compress::Gzip>, L<IO::Uncompress::Gunzip>, L<IO::Compress::Deflate>, L<IO::Uncompress::Inflate>, L<IO::Uncompress::RawInflate>, L<IO::Compress::Bzip2>, 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>
944 L<Compress::Zlib::FAQ|Compress::Zlib::FAQ>
946 L<File::GlobMapper|File::GlobMapper>, L<Archive::Zip|Archive::Zip>,
947 L<Archive::Tar|Archive::Tar>,
950 For RFC 1950, 1951 and 1952 see
951 F<http://www.faqs.org/rfcs/rfc1950.html>,
952 F<http://www.faqs.org/rfcs/rfc1951.html> and
953 F<http://www.faqs.org/rfcs/rfc1952.html>
955 The I<zlib> compression library was written by Jean-loup Gailly
956 F<gzip@prep.ai.mit.edu> and Mark Adler F<madler@alumni.caltech.edu>.
958 The primary site for the I<zlib> compression library is
959 F<http://www.zlib.org>.
961 The primary site for gzip is F<http://www.gzip.org>.
965 This module was written by Paul Marquess, F<pmqs@cpan.org>.
967 =head1 MODIFICATION HISTORY
969 See the Changes file.
971 =head1 COPYRIGHT AND LICENSE
973 Copyright (c) 2005-2008 Paul Marquess. All rights reserved.
975 This program is free software; you can redistribute it and/or
976 modify it under the same terms as Perl itself.