File: Lzma.pm

package info (click to toggle)
libio-compress-lzma-perl 2.101-1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye
  • size: 832 kB
  • sloc: perl: 7,348; makefile: 13
file content (777 lines) | stat: -rw-r--r-- 19,656 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
package IO::Compress::Lzma ;

use strict ;
use warnings;
use bytes;
require Exporter ;

use IO::Compress::Base 2.101 ;

use IO::Compress::Base::Common  2.101 qw(createSelfTiedObject);
use IO::Compress::Adapter::Lzma 2.101 ;



our ($VERSION, @ISA, @EXPORT_OK, %EXPORT_TAGS, $LzmaError);

$VERSION = '2.101';
$LzmaError = '';

@ISA    = qw(IO::Compress::Base Exporter);
@EXPORT_OK = qw( $LzmaError lzma ) ;
%EXPORT_TAGS = %IO::Compress::Base::EXPORT_TAGS ;
push @{ $EXPORT_TAGS{all} }, @EXPORT_OK ;
Exporter::export_ok_tags('all');



sub new
{
    my $class = shift ;

    my $obj = createSelfTiedObject($class, \$LzmaError);
    return $obj->_create(undef, @_);
}

sub lzma
{
    my $obj = createSelfTiedObject(undef, \$LzmaError);
    $obj->_def(@_);
}


sub mkHeader
{
    my $self = shift ;
    return '';

}

our %PARAMS = ('filter' => [IO::Compress::Base::Common::Parse_any, [] ],
              );
sub getExtraParams
{
    return %PARAMS ;
}



sub ckParams
{
    my $self = shift ;
    my $got = shift;

    # TODO - test that Filter ISA Lzma::Filter::Lzma1

    return 1 ;
}


sub mkComp
{
    my $self = shift ;
    my $got = shift ;

    my ($obj, $errstr, $errno) =
        IO::Compress::Adapter::Lzma::mkCompObject($got->getValue('filter'));

    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::UnLzma');
}

sub getFileInfo
{
    my $self = shift ;
    my $params = shift;
    my $file = shift ;

}

1;

__END__

=head1 NAME

IO::Compress::Lzma - Write lzma files/buffers

=head1 SYNOPSIS

    use IO::Compress::Lzma qw(lzma $LzmaError) ;

    my $status = lzma $input => $output [,OPTS]
        or die "lzma failed: $LzmaError\n";

    my $z = IO::Compress::Lzma->new( $output [,OPTS] )
        or die "lzma failed: $LzmaError\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() ;

    $LzmaError ;

    # 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 lzma
compressed data to files or buffer.

For reading lzma files/buffers, see the companion module
L<IO::Uncompress::UnLzma|IO::Uncompress::UnLzma>.

=head1 Functional Interface

A top-level function, C<lzma>, 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::Lzma qw(lzma $LzmaError) ;

    lzma $input_filename_or_reference => $output_filename_or_reference [,OPTS]
        or die "lzma failed: $LzmaError\n";

The functional interface needs Perl5.005 or better.

=head2 lzma $input_filename_or_reference => $output_filename_or_reference [, OPTS]

C<lzma> expects at least two parameters,
C<$input_filename_or_reference> and C<$output_filename_or_reference>
and zero or more optional parameters (see L</Optional Parameters>)

=head3 The C<$input_filename_or_reference> parameter

The parameter, C<$input_filename_or_reference>, 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_filename_or_reference> 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_filename_or_reference> 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_filename_or_reference> is a scalar reference, the input data
will be read from C<$$input_filename_or_reference>.

=item An array reference

If C<$input_filename_or_reference> 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_filename_or_reference> is a string that is delimited by the
characters "<" and ">" C<lzma> will assume that it is an
I<input fileglob string>. The input is the list of files that match the
fileglob.

See L<File::GlobMapper|File::GlobMapper> for more details.

=back

If the C<$input_filename_or_reference> parameter is any other type,
C<undef> will be returned.

=head3 The C<$output_filename_or_reference> parameter

The parameter C<$output_filename_or_reference> 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_filename_or_reference> 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_filename_or_reference> 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_filename_or_reference> is a scalar reference, the
compressed data will be stored in C<$$output_filename_or_reference>.

=item An Array Reference

If C<$output_filename_or_reference> is an array reference,
the compressed data will be pushed onto the array.

=item An Output FileGlob

If C<$output_filename_or_reference> is a string that is delimited by the
characters "<" and ">" C<lzma> will assume that it is an
I<output fileglob string>. The output is the list of files that match the
fileglob.

When C<$output_filename_or_reference> is an fileglob string,
C<$input_filename_or_reference> must also be a fileglob string. Anything
else is an error.

See L<File::GlobMapper|File::GlobMapper> for more details.

=back

If the C<$output_filename_or_reference> parameter is any other type,
C<undef> will be returned.

=head2 Notes

When C<$input_filename_or_reference> maps to multiple files/buffers and
C<$output_filename_or_reference> is a single
file/buffer the input files/buffers will be stored
in C<$output_filename_or_reference> as a concatenated series of compressed data streams.

=head2 Optional Parameters

The optional parameters for the one-shot function C<lzma>
are (for the most part) identical to those used with the OO interface defined in the
L</"Constructor Options"> section. The exceptions are listed below

=over 5

=item C<< AutoClose => 0|1 >>

This option applies to any input or output data streams to
C<lzma> 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<lzma> has
completed.

This parameter defaults to 0.

=item C<< BinModeIn => 0|1 >>

This option is now a no-op. All files will be read in binmode.

=item C<< Append => 0|1 >>

The behaviour of this option is dependent on the type of output data
stream.

=over 5

=item * A Buffer

If C<Append> is enabled, all compressed data will be append to the end of
the output buffer. Otherwise the output buffer will be cleared before any
compressed data is written to it.

=item * A Filename

If 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<Append> is enabled, the filehandle 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

When C<Append> is specified, and set to true, it will I<append> all compressed
data to the output data stream.

So when the output is a filehandle it will carry out a seek to the eof
before writing any compressed data. If the output is a filename, it will be opened for
appending. If the output is a buffer, all compressed data will be
appended to the existing buffer.

Conversely when C<Append> is not specified, or it is present and is set to
false, it will operate as follows.

When the output is a filename, it will truncate the contents of the file
before writing any compressed data. If the output is a filehandle
its position will not be changed. If the output is a buffer, it will be
wiped before any compressed data is output.

Defaults to 0.

=back

=head2 Examples

Here are a few example that show the capabilities of the module.

=head3 Streaming

This very simple command line example demonstrates the streaming capabilities of the module.
The code reads data from STDIN, compresses it, and writes the compressed data to STDOUT.

    $ echo hello world | perl -MIO::Compress::Lzma=lzma -e 'lzma \*STDIN => \*STDOUT' >output.lzma

The special filename "-" can be used as a standin for both C<\*STDIN> and C<\*STDOUT>,
so the above can be rewritten as

    $ echo hello world | perl -MIO::Compress::Lzma=lzma -e 'lzma "-" => "-"' >output.lzma

=head3 Compressing a file from the filesystem

To read the contents of the file C<file1.txt> and write the compressed
data to the file C<file1.txt.lzma>.

    use strict ;
    use warnings ;
    use IO::Compress::Lzma qw(lzma $LzmaError) ;

    my $input = "file1.txt";
    lzma $input => "$input.lzma"
        or die "lzma failed: $LzmaError\n";

=head3 Reading from a Filehandle and writing to an in-memory buffer

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::Lzma qw(lzma $LzmaError) ;
    use IO::File ;

    my $input = IO::File->new( "<file1.txt" )
        or die "Cannot open 'file1.txt': $!\n" ;
    my $buffer ;
    lzma $input => \$buffer
        or die "lzma failed: $LzmaError\n";

=head3 Compressing multiple files

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::Lzma qw(lzma $LzmaError) ;

    lzma '</my/home/*.txt>' => '<*.lzma>'
        or die "lzma failed: $LzmaError\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::Lzma qw(lzma $LzmaError) ;

    for my $input ( glob "/my/home/*.txt" )
    {
        my $output = "$input.lzma" ;
        lzma $input => $output
            or die "Error compressing '$input': $LzmaError\n";
    }

=head1 OO Interface

=head2 Constructor

The format of the constructor for C<IO::Compress::Lzma> is shown below

    my $z = IO::Compress::Lzma->new( $output [,OPTS] )
        or die "IO::Compress::Lzma failed: $LzmaError\n";

It returns an C<IO::Compress::Lzma> object on success and undef on failure.
The variable C<$LzmaError> will contain an error message on failure.

If you are running Perl 5.005 or better the object, C<$z>, returned from
IO::Compress::Lzma can be used exactly like an L<IO::File|IO::File> filehandle.
This means that all normal output file operations can be carried out
with C<$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::Lzma>::new will
return undef.

=head2 Constructor Options

C<OPTS> is any combination of zero or more 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::Lzma>
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<$output> is a buffer and C<Append> is enabled, all compressed data
will be append to the end of C<$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<< Filter => $filter >>

When present C< $filter > option must be an object of type C<Lzma::Filter::Lzma1>.
See L</Lzma::Filter::Lzma> for a definition of C<Lzma::Filter::Lzma1>.

If this option is not present an C<Lzma::Filter::Lzma1> object with default
values will be used.

=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.

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 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::Lzma 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::Lzma
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 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 IO::Compress::Lzma at present.

=over 5

=item :all

Imports C<lzma> and C<$LzmaError>.
Same as doing this

    use IO::Compress::Lzma qw(lzma $LzmaError) ;

=back

=head1 EXAMPLES

=head1 SUPPORT

General feedback/questions/bug reports should be sent to
L<https://github.com/pmqs/IO-Compress-Lzma/issues> (preferred) or
L<https://rt.cpan.org/Public/Dist/Display.html?Name=IO-Compress-Lzma>.

=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::Compress::Bzip2>, L<IO::Uncompress::Bunzip2>, L<IO::Uncompress::UnLzma>, L<IO::Compress::Xz>, L<IO::Uncompress::UnXz>, L<IO::Compress::Lzip>, L<IO::Uncompress::UnLzip>, L<IO::Compress::Lzop>, L<IO::Uncompress::UnLzop>, L<IO::Compress::Lzf>, L<IO::Uncompress::UnLzf>, L<IO::Compress::Zstd>, L<IO::Uncompress::UnZstd>, L<IO::Uncompress::AnyInflate>, L<IO::Uncompress::AnyUncompress>

L<IO::Compress::FAQ|IO::Compress::FAQ>

L<File::GlobMapper|File::GlobMapper>, L<Archive::Zip|Archive::Zip>,
L<Archive::Tar|Archive::Tar>,
L<IO::Zlib|IO::Zlib>

=head1 AUTHOR

This module was written by Paul Marquess, C<pmqs@cpan.org>.

=head1 MODIFICATION HISTORY

See the Changes file.

=head1 COPYRIGHT AND LICENSE

Copyright (c) 2005-2021 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.