1IO::Uncompress::RawInflUasteer(3C)ontributed Perl DocumeInOt:a:tUinocnompress::RawInflate(3)
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6 IO::Uncompress::RawInflate - Read RFC 1951 files/buffers
7
9 use IO::Uncompress::RawInflate qw(rawinflate $RawInflateError) ;
10
11 my $status = rawinflate $input => $output [,OPTS]
12 or die "rawinflate failed: $RawInflateError\n";
13
14 my $z = IO::Uncompress::RawInflate->new( $input [OPTS] )
15 or die "rawinflate failed: $RawInflateError\n";
16
17 $status = $z->read($buffer)
18 $status = $z->read($buffer, $length)
19 $status = $z->read($buffer, $length, $offset)
20 $line = $z->getline()
21 $char = $z->getc()
22 $char = $z->ungetc()
23 $char = $z->opened()
24
25 $status = $z->inflateSync()
26
27 $data = $z->trailingData()
28 $status = $z->nextStream()
29 $data = $z->getHeaderInfo()
30 $z->tell()
31 $z->seek($position, $whence)
32 $z->binmode()
33 $z->fileno()
34 $z->eof()
35 $z->close()
36
37 $RawInflateError ;
38
39 # IO::File mode
40
41 <$z>
42 read($z, $buffer);
43 read($z, $buffer, $length);
44 read($z, $buffer, $length, $offset);
45 tell($z)
46 seek($z, $position, $whence)
47 binmode($z)
48 fileno($z)
49 eof($z)
50 close($z)
51
53 This module provides a Perl interface that allows the reading of
54 files/buffers that conform to RFC 1951.
55
56 For writing RFC 1951 files/buffers, see the companion module
57 IO::Compress::RawDeflate.
58
60 A top-level function, "rawinflate", is provided to carry out "one-shot"
61 uncompression between buffers and/or files. For finer control over the
62 uncompression process, see the "OO Interface" section.
63
64 use IO::Uncompress::RawInflate qw(rawinflate $RawInflateError) ;
65
66 rawinflate $input_filename_or_reference => $output_filename_or_reference [,OPTS]
67 or die "rawinflate failed: $RawInflateError\n";
68
69 The functional interface needs Perl5.005 or better.
70
71 rawinflate $input_filename_or_reference => $output_filename_or_reference [,
72 OPTS]
73 "rawinflate" expects at least two parameters,
74 $input_filename_or_reference and $output_filename_or_reference and zero
75 or more optional parameters (see "Optional Parameters")
76
77 The $input_filename_or_reference parameter
78
79 The parameter, $input_filename_or_reference, is used to define the
80 source of the compressed data.
81
82 It can take one of the following forms:
83
84 A filename
85 If the $input_filename_or_reference parameter is a simple scalar,
86 it is assumed to be a filename. This file will be opened for
87 reading and the input data will be read from it.
88
89 A filehandle
90 If the $input_filename_or_reference parameter is a filehandle, the
91 input data will be read from it. The string '-' can be used as an
92 alias for standard input.
93
94 A scalar reference
95 If $input_filename_or_reference is a scalar reference, the input
96 data will be read from $$input_filename_or_reference.
97
98 An array reference
99 If $input_filename_or_reference is an array reference, each
100 element in the array must be a filename.
101
102 The input data will be read from each file in turn.
103
104 The complete array will be walked to ensure that it only contains
105 valid filenames before any data is uncompressed.
106
107 An Input FileGlob string
108 If $input_filename_or_reference is a string that is delimited by
109 the characters "<" and ">" "rawinflate" will assume that it is an
110 input fileglob string. The input is the list of files that match
111 the fileglob.
112
113 See File::GlobMapper for more details.
114
115 If the $input_filename_or_reference parameter is any other type,
116 "undef" will be returned.
117
118 The $output_filename_or_reference parameter
119
120 The parameter $output_filename_or_reference is used to control the
121 destination of the uncompressed data. This parameter can take one of
122 these forms.
123
124 A filename
125 If the $output_filename_or_reference parameter is a simple scalar,
126 it is assumed to be a filename. This file will be opened for
127 writing and the uncompressed data will be written to it.
128
129 A filehandle
130 If the $output_filename_or_reference parameter is a filehandle,
131 the uncompressed data will be written to it. The string '-' can
132 be used as an alias for standard output.
133
134 A scalar reference
135 If $output_filename_or_reference is a scalar reference, the
136 uncompressed data will be stored in
137 $$output_filename_or_reference.
138
139 An Array Reference
140 If $output_filename_or_reference is an array reference, the
141 uncompressed data will be pushed onto the array.
142
143 An Output FileGlob
144 If $output_filename_or_reference is a string that is delimited by
145 the characters "<" and ">" "rawinflate" will assume that it is an
146 output fileglob string. The output is the list of files that match
147 the fileglob.
148
149 When $output_filename_or_reference is an fileglob string,
150 $input_filename_or_reference must also be a fileglob string.
151 Anything else is an error.
152
153 See File::GlobMapper for more details.
154
155 If the $output_filename_or_reference parameter is any other type,
156 "undef" will be returned.
157
158 Notes
159 When $input_filename_or_reference maps to multiple compressed
160 files/buffers and $output_filename_or_reference is a single
161 file/buffer, after uncompression $output_filename_or_reference will
162 contain a concatenation of all the uncompressed data from each of the
163 input files/buffers.
164
165 Optional Parameters
166 The optional parameters for the one-shot function "rawinflate" are (for
167 the most part) identical to those used with the OO interface defined in
168 the "Constructor Options" section. The exceptions are listed below
169
170 "AutoClose => 0|1"
171 This option applies to any input or output data streams to
172 "rawinflate" that are filehandles.
173
174 If "AutoClose" is specified, and the value is true, it will result
175 in all input and/or output filehandles being closed once
176 "rawinflate" has completed.
177
178 This parameter defaults to 0.
179
180 "BinModeOut => 0|1"
181 This option is now a no-op. All files will be written in binmode.
182
183 "Append => 0|1"
184 The behaviour of this option is dependent on the type of output
185 data stream.
186
187 • A Buffer
188
189 If "Append" is enabled, all uncompressed data will be append
190 to the end of the output buffer. Otherwise the output buffer
191 will be cleared before any uncompressed data is written to
192 it.
193
194 • A Filename
195
196 If "Append" is enabled, the file will be opened in append
197 mode. Otherwise the contents of the file, if any, will be
198 truncated before any uncompressed data is written to it.
199
200 • A Filehandle
201
202 If "Append" is enabled, the filehandle will be positioned to
203 the end of the file via a call to "seek" before any
204 uncompressed data is written to it. Otherwise the file
205 pointer will not be moved.
206
207 When "Append" is specified, and set to true, it will append all
208 uncompressed data to the output data stream.
209
210 So when the output is a filehandle it will carry out a seek to the
211 eof before writing any uncompressed data. If the output is a
212 filename, it will be opened for appending. If the output is a
213 buffer, all uncompressed data will be appended to the existing
214 buffer.
215
216 Conversely when "Append" is not specified, or it is present and is
217 set to false, it will operate as follows.
218
219 When the output is a filename, it will truncate the contents of
220 the file before writing any uncompressed data. If the output is a
221 filehandle its position will not be changed. If the output is a
222 buffer, it will be wiped before any uncompressed data is output.
223
224 Defaults to 0.
225
226 "MultiStream => 0|1"
227 This option is a no-op.
228
229 "TrailingData => $scalar"
230 Returns the data, if any, that is present immediately after the
231 compressed data stream once uncompression is complete.
232
233 This option can be used when there is useful information
234 immediately following the compressed data stream, and you don't
235 know the length of the compressed data stream.
236
237 If the input is a buffer, "trailingData" will return everything
238 from the end of the compressed data stream to the end of the
239 buffer.
240
241 If the input is a filehandle, "trailingData" will return the data
242 that is left in the filehandle input buffer once the end of the
243 compressed data stream has been reached. You can then use the
244 filehandle to read the rest of the input file.
245
246 Don't bother using "trailingData" if the input is a filename.
247
248 If you know the length of the compressed data stream before you
249 start uncompressing, you can avoid having to use "trailingData" by
250 setting the "InputLength" option.
251
252 OneShot Examples
253 To read the contents of the file "file1.txt.1951" and write the
254 uncompressed data to the file "file1.txt".
255
256 use strict ;
257 use warnings ;
258 use IO::Uncompress::RawInflate qw(rawinflate $RawInflateError) ;
259
260 my $input = "file1.txt.1951";
261 my $output = "file1.txt";
262 rawinflate $input => $output
263 or die "rawinflate failed: $RawInflateError\n";
264
265 To read from an existing Perl filehandle, $input, and write the
266 uncompressed data to a buffer, $buffer.
267
268 use strict ;
269 use warnings ;
270 use IO::Uncompress::RawInflate qw(rawinflate $RawInflateError) ;
271 use IO::File ;
272
273 my $input = IO::File->new( "<file1.txt.1951" )
274 or die "Cannot open 'file1.txt.1951': $!\n" ;
275 my $buffer ;
276 rawinflate $input => \$buffer
277 or die "rawinflate failed: $RawInflateError\n";
278
279 To uncompress all files in the directory "/my/home" that match
280 "*.txt.1951" and store the compressed data in the same directory
281
282 use strict ;
283 use warnings ;
284 use IO::Uncompress::RawInflate qw(rawinflate $RawInflateError) ;
285
286 rawinflate '</my/home/*.txt.1951>' => '</my/home/#1.txt>'
287 or die "rawinflate failed: $RawInflateError\n";
288
289 and if you want to compress each file one at a time, this will do the
290 trick
291
292 use strict ;
293 use warnings ;
294 use IO::Uncompress::RawInflate qw(rawinflate $RawInflateError) ;
295
296 for my $input ( glob "/my/home/*.txt.1951" )
297 {
298 my $output = $input;
299 $output =~ s/.1951// ;
300 rawinflate $input => $output
301 or die "Error compressing '$input': $RawInflateError\n";
302 }
303
305 Constructor
306 The format of the constructor for IO::Uncompress::RawInflate is shown
307 below
308
309 my $z = IO::Uncompress::RawInflate->new( $input [OPTS] )
310 or die "IO::Uncompress::RawInflate failed: $RawInflateError\n";
311
312 The constructor takes one mandatory parameter, $input, defined below,
313 and zero or more "OPTS", defined in "Constructor Options".
314
315 Returns an "IO::Uncompress::RawInflate" object on success and undef on
316 failure. The variable $RawInflateError will contain an error message
317 on failure.
318
319 If you are running Perl 5.005 or better the object, $z, returned from
320 IO::Uncompress::RawInflate can be used exactly like an IO::File
321 filehandle. This means that all normal input file operations can be
322 carried out with $z. For example, to read a line from a compressed
323 file/buffer you can use either of these forms
324
325 $line = $z->getline();
326 $line = <$z>;
327
328 Below is a simple exaple of using the OO interface to read the
329 compressed file "myfile.1951" and write its contents to stdout.
330
331 my $filename = "myfile.1951";
332 my $z = IO::Uncompress::RawInflate->new($filename)
333 or die "IO::Uncompress::RawInflate failed: $RawInflateError\n";
334
335 while (<$z>) {
336 print $_;
337 }
338 $z->close();
339
340 See "EXAMPLES" for further examples
341
342 The mandatory parameter $input is used to determine the source of the
343 compressed data. This parameter can take one of three forms.
344
345 A filename
346 If the $input parameter is a scalar, it is assumed to be a
347 filename. This file will be opened for reading and the compressed
348 data will be read from it.
349
350 A filehandle
351 If the $input parameter is a filehandle, the compressed data will
352 be read from it. The string '-' can be used as an alias for
353 standard input.
354
355 A scalar reference
356 If $input is a scalar reference, the compressed data will be read
357 from $$input.
358
359 Constructor Options
360 The option names defined below are case insensitive and can be
361 optionally prefixed by a '-'. So all of the following are valid
362
363 -AutoClose
364 -autoclose
365 AUTOCLOSE
366 autoclose
367
368 OPTS is a combination of the following options:
369
370 "AutoClose => 0|1"
371 This option is only valid when the $input parameter is a
372 filehandle. If specified, and the value is true, it will result in
373 the file being closed once either the "close" method is called or
374 the IO::Uncompress::RawInflate object is destroyed.
375
376 This parameter defaults to 0.
377
378 "MultiStream => 0|1"
379 Allows multiple concatenated compressed streams to be treated as a
380 single compressed stream. Decompression will stop once either the
381 end of the file/buffer is reached, an error is encountered
382 (premature eof, corrupt compressed data) or the end of a stream is
383 not immediately followed by the start of another stream.
384
385 This parameter defaults to 0.
386
387 "Prime => $string"
388 This option will uncompress the contents of $string before
389 processing the input file/buffer.
390
391 This option can be useful when the compressed data is embedded in
392 another file/data structure and it is not possible to work out
393 where the compressed data begins without having to read the first
394 few bytes. If this is the case, the uncompression can be primed
395 with these bytes using this option.
396
397 "Transparent => 0|1"
398 If this option is set and the input file/buffer is not compressed
399 data, the module will allow reading of it anyway.
400
401 In addition, if the input file/buffer does contain compressed data
402 and there is non-compressed data immediately following it, setting
403 this option will make this module treat the whole file/buffer as a
404 single data stream.
405
406 This option defaults to 1.
407
408 "BlockSize => $num"
409 When reading the compressed input data, IO::Uncompress::RawInflate
410 will read it in blocks of $num bytes.
411
412 This option defaults to 4096.
413
414 "InputLength => $size"
415 When present this option will limit the number of compressed bytes
416 read from the input file/buffer to $size. This option can be used
417 in the situation where there is useful data directly after the
418 compressed data stream and you know beforehand the exact length of
419 the compressed data stream.
420
421 This option is mostly used when reading from a filehandle, in
422 which case the file pointer will be left pointing to the first
423 byte directly after the compressed data stream.
424
425 This option defaults to off.
426
427 "Append => 0|1"
428 This option controls what the "read" method does with uncompressed
429 data.
430
431 If set to 1, all uncompressed data will be appended to the output
432 parameter of the "read" method.
433
434 If set to 0, the contents of the output parameter of the "read"
435 method will be overwritten by the uncompressed data.
436
437 Defaults to 0.
438
439 "Strict => 0|1"
440 This option is a no-op.
441
443 read
444 Usage is
445
446 $status = $z->read($buffer)
447
448 Reads a block of compressed data (the size of the compressed block is
449 determined by the "Buffer" option in the constructor), uncompresses it
450 and writes any uncompressed data into $buffer. If the "Append"
451 parameter is set in the constructor, the uncompressed data will be
452 appended to the $buffer parameter. Otherwise $buffer will be
453 overwritten.
454
455 Returns the number of uncompressed bytes written to $buffer, zero if
456 eof or a negative number on error.
457
458 read
459 Usage is
460
461 $status = $z->read($buffer, $length)
462 $status = $z->read($buffer, $length, $offset)
463
464 $status = read($z, $buffer, $length)
465 $status = read($z, $buffer, $length, $offset)
466
467 Attempt to read $length bytes of uncompressed data into $buffer.
468
469 The main difference between this form of the "read" method and the
470 previous one, is that this one will attempt to return exactly $length
471 bytes. The only circumstances that this function will not is if end-of-
472 file or an IO error is encountered.
473
474 Returns the number of uncompressed bytes written to $buffer, zero if
475 eof or a negative number on error.
476
477 getline
478 Usage is
479
480 $line = $z->getline()
481 $line = <$z>
482
483 Reads a single line.
484
485 This method fully supports the use of the variable $/ (or
486 $INPUT_RECORD_SEPARATOR or $RS when "English" is in use) to determine
487 what constitutes an end of line. Paragraph mode, record mode and file
488 slurp mode are all supported.
489
490 getc
491 Usage is
492
493 $char = $z->getc()
494
495 Read a single character.
496
497 ungetc
498 Usage is
499
500 $char = $z->ungetc($string)
501
502 inflateSync
503 Usage is
504
505 $status = $z->inflateSync()
506
507 TODO
508
509 getHeaderInfo
510 Usage is
511
512 $hdr = $z->getHeaderInfo();
513 @hdrs = $z->getHeaderInfo();
514
515 This method returns either a hash reference (in scalar context) or a
516 list or hash references (in array context) that contains information
517 about each of the header fields in the compressed data stream(s).
518
519 tell
520 Usage is
521
522 $z->tell()
523 tell $z
524
525 Returns the uncompressed file offset.
526
527 eof
528 Usage is
529
530 $z->eof();
531 eof($z);
532
533 Returns true if the end of the compressed input stream has been
534 reached.
535
536 seek
537 $z->seek($position, $whence);
538 seek($z, $position, $whence);
539
540 Provides a sub-set of the "seek" functionality, with the restriction
541 that it is only legal to seek forward in the input file/buffer. It is
542 a fatal error to attempt to seek backward.
543
544 Note that the implementation of "seek" in this module does not provide
545 true random access to a compressed file/buffer. It works by
546 uncompressing data from the current offset in the file/buffer until it
547 reaches the uncompressed offset specified in the parameters to "seek".
548 For very small files this may be acceptable behaviour. For large files
549 it may cause an unacceptable delay.
550
551 The $whence parameter takes one the usual values, namely SEEK_SET,
552 SEEK_CUR or SEEK_END.
553
554 Returns 1 on success, 0 on failure.
555
556 binmode
557 Usage is
558
559 $z->binmode
560 binmode $z ;
561
562 This is a noop provided for completeness.
563
564 opened
565 $z->opened()
566
567 Returns true if the object currently refers to a opened file/buffer.
568
569 autoflush
570 my $prev = $z->autoflush()
571 my $prev = $z->autoflush(EXPR)
572
573 If the $z object is associated with a file or a filehandle, this method
574 returns the current autoflush setting for the underlying filehandle. If
575 "EXPR" is present, and is non-zero, it will enable flushing after every
576 write/print operation.
577
578 If $z is associated with a buffer, this method has no effect and always
579 returns "undef".
580
581 Note that the special variable $| cannot be used to set or retrieve the
582 autoflush setting.
583
584 input_line_number
585 $z->input_line_number()
586 $z->input_line_number(EXPR)
587
588 Returns the current uncompressed line number. If "EXPR" is present it
589 has the effect of setting the line number. Note that setting the line
590 number does not change the current position within the file/buffer
591 being read.
592
593 The contents of $/ are used to determine what constitutes a line
594 terminator.
595
596 fileno
597 $z->fileno()
598 fileno($z)
599
600 If the $z object is associated with a file or a filehandle, "fileno"
601 will return the underlying file descriptor. Once the "close" method is
602 called "fileno" will return "undef".
603
604 If the $z object is associated with a buffer, this method will return
605 "undef".
606
607 close
608 $z->close() ;
609 close $z ;
610
611 Closes the output file/buffer.
612
613 For most versions of Perl this method will be automatically invoked if
614 the IO::Uncompress::RawInflate object is destroyed (either explicitly
615 or by the variable with the reference to the object going out of
616 scope). The exceptions are Perl versions 5.005 through 5.00504 and
617 5.8.0. In these cases, the "close" method will be called automatically,
618 but not until global destruction of all live objects when the program
619 is terminating.
620
621 Therefore, if you want your scripts to be able to run on all versions
622 of Perl, you should call "close" explicitly and not rely on automatic
623 closing.
624
625 Returns true on success, otherwise 0.
626
627 If the "AutoClose" option has been enabled when the
628 IO::Uncompress::RawInflate object was created, and the object is
629 associated with a file, the underlying file will also be closed.
630
631 nextStream
632 Usage is
633
634 my $status = $z->nextStream();
635
636 Skips to the next compressed data stream in the input file/buffer. If a
637 new compressed data stream is found, the eof marker will be cleared and
638 $. will be reset to 0.
639
640 Returns 1 if a new stream was found, 0 if none was found, and -1 if an
641 error was encountered.
642
643 trailingData
644 Usage is
645
646 my $data = $z->trailingData();
647
648 Returns the data, if any, that is present immediately after the
649 compressed data stream once uncompression is complete. It only makes
650 sense to call this method once the end of the compressed data stream
651 has been encountered.
652
653 This option can be used when there is useful information immediately
654 following the compressed data stream, and you don't know the length of
655 the compressed data stream.
656
657 If the input is a buffer, "trailingData" will return everything from
658 the end of the compressed data stream to the end of the buffer.
659
660 If the input is a filehandle, "trailingData" will return the data that
661 is left in the filehandle input buffer once the end of the compressed
662 data stream has been reached. You can then use the filehandle to read
663 the rest of the input file.
664
665 Don't bother using "trailingData" if the input is a filename.
666
667 If you know the length of the compressed data stream before you start
668 uncompressing, you can avoid having to use "trailingData" by setting
669 the "InputLength" option in the constructor.
670
672 No symbolic constants are required by IO::Uncompress::RawInflate at
673 present.
674
675 :all Imports "rawinflate" and $RawInflateError. Same as doing this
676
677 use IO::Uncompress::RawInflate qw(rawinflate $RawInflateError) ;
678
680 Working with Net::FTP
681 See IO::Compress::FAQ
682
684 General feedback/questions/bug reports should be sent to
685 <https://github.com/pmqs/IO-Compress/issues> (preferred) or
686 <https://rt.cpan.org/Public/Dist/Display.html?Name=IO-Compress>.
687
689 Compress::Zlib, IO::Compress::Gzip, IO::Uncompress::Gunzip,
690 IO::Compress::Deflate, IO::Uncompress::Inflate,
691 IO::Compress::RawDeflate, IO::Compress::Bzip2, IO::Uncompress::Bunzip2,
692 IO::Compress::Lzma, IO::Uncompress::UnLzma, IO::Compress::Xz,
693 IO::Uncompress::UnXz, IO::Compress::Lzip, IO::Uncompress::UnLzip,
694 IO::Compress::Lzop, IO::Uncompress::UnLzop, IO::Compress::Lzf,
695 IO::Uncompress::UnLzf, IO::Compress::Zstd, IO::Uncompress::UnZstd,
696 IO::Uncompress::AnyInflate, IO::Uncompress::AnyUncompress
697
698 IO::Compress::FAQ
699
700 File::GlobMapper, Archive::Zip, Archive::Tar, IO::Zlib
701
702 For RFC 1950, 1951 and 1952 see
703 <https://datatracker.ietf.org/doc/html/rfc1950>,
704 <https://datatracker.ietf.org/doc/html/rfc1951> and
705 <https://datatracker.ietf.org/doc/html/rfc1952>
706
707 The zlib compression library was written by Jean-loup Gailly
708 "gzip@prep.ai.mit.edu" and Mark Adler "madler@alumni.caltech.edu".
709
710 The primary site for the zlib compression library is
711 <http://www.zlib.org>.
712
713 The primary site for the zlib-ng compression library is
714 <https://github.com/zlib-ng/zlib-ng>.
715
716 The primary site for gzip is <http://www.gzip.org>.
717
719 This module was written by Paul Marquess, "pmqs@cpan.org".
720
722 See the Changes file.
723
725 Copyright (c) 2005-2023 Paul Marquess. All rights reserved.
726
727 This program is free software; you can redistribute it and/or modify it
728 under the same terms as Perl itself.
729
730
731
732perl v5.38.0 2023-07-26 IO::Uncompress::RawInflate(3)