Commit | Line | Data |
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1 | package IO::Uncompress::Inflate ; |
2 | # for RFC1950 |
3 | |
4 | use strict ; |
5 | use warnings; |
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6 | use bytes; |
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7 | |
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8 | use IO::Compress::Base::Common qw(:Status createSelfTiedObject); |
9 | use IO::Compress::Zlib::Constants; |
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10 | |
11 | use IO::Uncompress::RawInflate ; |
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12 | |
13 | require Exporter ; |
14 | our ($VERSION, @ISA, @EXPORT_OK, %EXPORT_TAGS, $InflateError); |
15 | |
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16 | $VERSION = '2.000_08'; |
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17 | $InflateError = ''; |
18 | |
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19 | @ISA = qw( Exporter IO::Uncompress::RawInflate ); |
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20 | @EXPORT_OK = qw( $InflateError inflate ) ; |
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21 | %EXPORT_TAGS = %IO::Uncompress::RawInflate::DEFLATE_CONSTANTS ; |
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22 | push @{ $EXPORT_TAGS{all} }, @EXPORT_OK ; |
23 | Exporter::export_ok_tags('all'); |
24 | |
25 | |
26 | sub new |
27 | { |
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28 | my $class = shift ; |
29 | my $obj = createSelfTiedObject($class, \$InflateError); |
30 | |
31 | $obj->_create(undef, 0, @_); |
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32 | } |
33 | |
34 | sub inflate |
35 | { |
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36 | my $obj = createSelfTiedObject(undef, \$InflateError); |
37 | return $obj->_inf(@_); |
38 | } |
39 | |
40 | sub getExtraParams |
41 | { |
42 | return (); |
43 | } |
44 | |
45 | sub ckParams |
46 | { |
47 | my $self = shift ; |
48 | my $got = shift ; |
49 | |
50 | # gunzip always needs adler32 |
51 | $got->value('ADLER32' => 1); |
52 | |
53 | return 1; |
54 | } |
55 | |
56 | sub ckMagic |
57 | { |
58 | my $self = shift; |
59 | |
60 | my $magic ; |
61 | $self->smartReadExact(\$magic, ZLIB_HEADER_SIZE); |
62 | |
63 | *$self->{HeaderPending} = $magic ; |
64 | |
65 | return $self->HeaderError("Header size is " . |
66 | ZLIB_HEADER_SIZE . " bytes") |
67 | if length $magic != ZLIB_HEADER_SIZE; |
68 | |
69 | return $self->HeaderError("CRC mismatch.") |
70 | if ! isZlibMagic($magic) ; |
71 | |
72 | *$self->{Type} = 'rfc1950'; |
73 | return $magic; |
74 | } |
75 | |
76 | sub readHeader |
77 | { |
78 | my $self = shift; |
79 | my $magic = shift ; |
80 | |
81 | return $self->_readDeflateHeader($magic) ; |
82 | } |
83 | |
84 | sub chkTrailer |
85 | { |
86 | my $self = shift; |
87 | my $trailer = shift; |
88 | |
89 | my $ADLER32 = unpack("N", $trailer) ; |
90 | *$self->{Info}{ADLER32} = $ADLER32; |
91 | return $self->TrailerError("CRC mismatch") |
92 | if *$self->{Strict} && $ADLER32 != *$self->{Uncomp}->adler32() ; |
93 | |
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94 | return STATUS_OK; |
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95 | } |
96 | |
97 | |
98 | |
99 | sub isZlibMagic |
100 | { |
101 | my $buffer = shift ; |
102 | return 0 if length $buffer < ZLIB_HEADER_SIZE ; |
103 | my $hdr = unpack("n", $buffer) ; |
104 | return $hdr % 31 == 0 ; |
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105 | } |
106 | |
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107 | sub bits |
108 | { |
109 | my $data = shift ; |
110 | my $offset = shift ; |
111 | my $mask = shift ; |
112 | |
113 | ($data >> $offset ) & $mask & 0xFF ; |
114 | } |
115 | |
116 | |
117 | sub _readDeflateHeader |
118 | { |
119 | my ($self, $buffer) = @_ ; |
120 | |
121 | # if (! $buffer) { |
122 | # $self->smartReadExact(\$buffer, ZLIB_HEADER_SIZE); |
123 | # |
124 | # *$self->{HeaderPending} = $buffer ; |
125 | # |
126 | # return $self->HeaderError("Header size is " . |
127 | # ZLIB_HEADER_SIZE . " bytes") |
128 | # if length $buffer != ZLIB_HEADER_SIZE; |
129 | # |
130 | # return $self->HeaderError("CRC mismatch.") |
131 | # if ! isZlibMagic($buffer) ; |
132 | # } |
133 | |
134 | my ($CMF, $FLG) = unpack "C C", $buffer; |
135 | my $FDICT = bits($FLG, ZLIB_FLG_FDICT_OFFSET, ZLIB_FLG_FDICT_BITS ), |
136 | |
137 | my $cm = bits($CMF, ZLIB_CMF_CM_OFFSET, ZLIB_CMF_CM_BITS) ; |
138 | $cm == ZLIB_CMF_CM_DEFLATED |
139 | or return $self->HeaderError("Not Deflate (CM is $cm)") ; |
140 | |
141 | my $DICTID; |
142 | if ($FDICT) { |
143 | $self->smartReadExact(\$buffer, ZLIB_FDICT_SIZE) |
144 | or return $self->TruncatedHeader("FDICT"); |
145 | |
146 | $DICTID = unpack("N", $buffer) ; |
147 | } |
148 | |
149 | *$self->{Type} = 'rfc1950'; |
150 | |
151 | return { |
152 | 'Type' => 'rfc1950', |
153 | 'FingerprintLength' => ZLIB_HEADER_SIZE, |
154 | 'HeaderLength' => ZLIB_HEADER_SIZE, |
155 | 'TrailerLength' => ZLIB_TRAILER_SIZE, |
156 | 'Header' => $buffer, |
157 | |
158 | CMF => $CMF , |
159 | CM => bits($CMF, ZLIB_CMF_CM_OFFSET, ZLIB_CMF_CM_BITS ), |
160 | CINFO => bits($CMF, ZLIB_CMF_CINFO_OFFSET, ZLIB_CMF_CINFO_BITS ), |
161 | FLG => $FLG , |
162 | FCHECK => bits($FLG, ZLIB_FLG_FCHECK_OFFSET, ZLIB_FLG_FCHECK_BITS), |
163 | FDICT => bits($FLG, ZLIB_FLG_FDICT_OFFSET, ZLIB_FLG_FDICT_BITS ), |
164 | FLEVEL => bits($FLG, ZLIB_FLG_LEVEL_OFFSET, ZLIB_FLG_LEVEL_BITS ), |
165 | DICTID => $DICTID , |
166 | |
167 | }; |
168 | } |
169 | |
170 | |
171 | |
172 | |
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173 | 1 ; |
174 | |
175 | __END__ |
176 | |
177 | |
178 | =head1 NAME |
179 | |
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180 | |
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181 | IO::Uncompress::Inflate - Perl interface to read RFC 1950 files/buffers |
182 | |
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183 | |
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184 | =head1 SYNOPSIS |
185 | |
186 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
187 | |
188 | my $status = inflate $input => $output [,OPTS] |
189 | or die "inflate failed: $InflateError\n"; |
190 | |
191 | my $z = new IO::Uncompress::Inflate $input [OPTS] |
192 | or die "inflate failed: $InflateError\n"; |
193 | |
194 | $status = $z->read($buffer) |
195 | $status = $z->read($buffer, $length) |
196 | $status = $z->read($buffer, $length, $offset) |
197 | $line = $z->getline() |
198 | $char = $z->getc() |
199 | $char = $z->ungetc() |
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200 | $char = $z->opened() |
201 | |
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202 | $status = $z->inflateSync() |
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203 | |
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204 | $z->trailingData() |
205 | $data = $z->getHeaderInfo() |
206 | $z->tell() |
207 | $z->seek($position, $whence) |
208 | $z->binmode() |
209 | $z->fileno() |
210 | $z->eof() |
211 | $z->close() |
212 | |
213 | $InflateError ; |
214 | |
215 | # IO::File mode |
216 | |
217 | <$z> |
218 | read($z, $buffer); |
219 | read($z, $buffer, $length); |
220 | read($z, $buffer, $length, $offset); |
221 | tell($z) |
222 | seek($z, $position, $whence) |
223 | binmode($z) |
224 | fileno($z) |
225 | eof($z) |
226 | close($z) |
227 | |
228 | |
229 | =head1 DESCRIPTION |
230 | |
231 | |
232 | |
233 | B<WARNING -- This is a Beta release>. |
234 | |
235 | =over 5 |
236 | |
237 | =item * DO NOT use in production code. |
238 | |
239 | =item * The documentation is incomplete in places. |
240 | |
241 | =item * Parts of the interface defined here are tentative. |
242 | |
243 | =item * Please report any problems you find. |
244 | |
245 | =back |
246 | |
247 | |
248 | |
249 | |
250 | |
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251 | This module provides a Perl interface that allows the reading of |
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252 | files/buffers that conform to RFC 1950. |
253 | |
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254 | For writing RFC 1950 files/buffers, see the companion module IO::Compress::Deflate. |
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255 | |
256 | |
257 | |
258 | =head1 Functional Interface |
259 | |
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260 | A top-level function, C<inflate>, is provided to carry out |
261 | "one-shot" uncompression between buffers and/or files. For finer |
262 | control over the uncompression process, see the L</"OO Interface"> |
263 | section. |
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264 | |
265 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
266 | |
267 | inflate $input => $output [,OPTS] |
268 | or die "inflate failed: $InflateError\n"; |
269 | |
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270 | |
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271 | |
272 | The functional interface needs Perl5.005 or better. |
273 | |
274 | |
275 | =head2 inflate $input => $output [, OPTS] |
276 | |
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277 | |
278 | C<inflate> expects at least two parameters, C<$input> and C<$output>. |
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279 | |
280 | =head3 The C<$input> parameter |
281 | |
282 | The parameter, C<$input>, is used to define the source of |
283 | the compressed data. |
284 | |
285 | It can take one of the following forms: |
286 | |
287 | =over 5 |
288 | |
289 | =item A filename |
290 | |
291 | If the C<$input> parameter is a simple scalar, it is assumed to be a |
292 | filename. This file will be opened for reading and the input data |
293 | will be read from it. |
294 | |
295 | =item A filehandle |
296 | |
297 | If the C<$input> parameter is a filehandle, the input data will be |
298 | read from it. |
299 | The string '-' can be used as an alias for standard input. |
300 | |
301 | =item A scalar reference |
302 | |
303 | If C<$input> is a scalar reference, the input data will be read |
304 | from C<$$input>. |
305 | |
306 | =item An array reference |
307 | |
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308 | If C<$input> is an array reference, each element in the array must be a |
309 | filename. |
310 | |
311 | The input data will be read from each file in turn. |
312 | |
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313 | The complete array will be walked to ensure that it only |
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314 | contains valid filenames before any data is uncompressed. |
315 | |
316 | |
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317 | |
318 | =item An Input FileGlob string |
319 | |
320 | If C<$input> is a string that is delimited by the characters "<" and ">" |
321 | C<inflate> will assume that it is an I<input fileglob string>. The |
322 | input is the list of files that match the fileglob. |
323 | |
324 | If the fileglob does not match any files ... |
325 | |
326 | See L<File::GlobMapper|File::GlobMapper> for more details. |
327 | |
328 | |
329 | =back |
330 | |
331 | If the C<$input> parameter is any other type, C<undef> will be returned. |
332 | |
333 | |
334 | |
335 | =head3 The C<$output> parameter |
336 | |
337 | The parameter C<$output> is used to control the destination of the |
338 | uncompressed data. This parameter can take one of these forms. |
339 | |
340 | =over 5 |
341 | |
342 | =item A filename |
343 | |
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344 | If the C<$output> parameter is a simple scalar, it is assumed to be a |
345 | filename. This file will be opened for writing and the uncompressed |
346 | data will be written to it. |
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347 | |
348 | =item A filehandle |
349 | |
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350 | If the C<$output> parameter is a filehandle, the uncompressed data |
351 | will be written to it. |
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352 | The string '-' can be used as an alias for standard output. |
353 | |
354 | |
355 | =item A scalar reference |
356 | |
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357 | If C<$output> is a scalar reference, the uncompressed data will be |
358 | stored in C<$$output>. |
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359 | |
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360 | |
361 | |
362 | =item An Array Reference |
363 | |
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364 | If C<$output> is an array reference, the uncompressed data will be |
365 | pushed onto the array. |
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366 | |
367 | =item An Output FileGlob |
368 | |
369 | If C<$output> is a string that is delimited by the characters "<" and ">" |
370 | C<inflate> will assume that it is an I<output fileglob string>. The |
371 | output is the list of files that match the fileglob. |
372 | |
373 | When C<$output> is an fileglob string, C<$input> must also be a fileglob |
374 | string. Anything else is an error. |
375 | |
376 | =back |
377 | |
378 | If the C<$output> parameter is any other type, C<undef> will be returned. |
379 | |
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380 | |
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381 | |
382 | =head2 Notes |
383 | |
384 | When C<$input> maps to multiple files/buffers and C<$output> is a single |
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385 | file/buffer the uncompressed input files/buffers will all be stored |
386 | in C<$output> as a single uncompressed stream. |
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387 | |
388 | |
389 | |
390 | =head2 Optional Parameters |
391 | |
392 | Unless specified below, the optional parameters for C<inflate>, |
393 | C<OPTS>, are the same as those used with the OO interface defined in the |
394 | L</"Constructor Options"> section below. |
395 | |
396 | =over 5 |
397 | |
398 | =item AutoClose =E<gt> 0|1 |
399 | |
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400 | This option applies to any input or output data streams to |
401 | C<inflate> that are filehandles. |
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402 | |
403 | If C<AutoClose> is specified, and the value is true, it will result in all |
404 | input and/or output filehandles being closed once C<inflate> has |
405 | completed. |
406 | |
407 | This parameter defaults to 0. |
408 | |
409 | |
410 | |
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411 | =item BinModeOut =E<gt> 0|1 |
412 | |
413 | When writing to a file or filehandle, set C<binmode> before writing to the |
414 | file. |
415 | |
416 | Defaults to 0. |
417 | |
418 | |
419 | |
420 | |
421 | |
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422 | =item -Append =E<gt> 0|1 |
423 | |
424 | TODO |
425 | |
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426 | =item -MultiStream =E<gt> 0|1 |
427 | |
428 | Creates a new stream after each file. |
429 | |
430 | Defaults to 1. |
431 | |
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432 | |
433 | |
434 | =back |
435 | |
436 | |
437 | |
438 | |
439 | =head2 Examples |
440 | |
441 | To read the contents of the file C<file1.txt.1950> and write the |
442 | compressed data to the file C<file1.txt>. |
443 | |
444 | use strict ; |
445 | use warnings ; |
446 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
447 | |
448 | my $input = "file1.txt.1950"; |
449 | my $output = "file1.txt"; |
450 | inflate $input => $output |
451 | or die "inflate failed: $InflateError\n"; |
452 | |
453 | |
454 | To read from an existing Perl filehandle, C<$input>, and write the |
455 | uncompressed data to a buffer, C<$buffer>. |
456 | |
457 | use strict ; |
458 | use warnings ; |
459 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
460 | use IO::File ; |
461 | |
462 | my $input = new IO::File "<file1.txt.1950" |
463 | or die "Cannot open 'file1.txt.1950': $!\n" ; |
464 | my $buffer ; |
465 | inflate $input => \$buffer |
466 | or die "inflate failed: $InflateError\n"; |
467 | |
468 | To uncompress all files in the directory "/my/home" that match "*.txt.1950" and store the compressed data in the same directory |
469 | |
470 | use strict ; |
471 | use warnings ; |
472 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
473 | |
474 | inflate '</my/home/*.txt.1950>' => '</my/home/#1.txt>' |
475 | or die "inflate failed: $InflateError\n"; |
476 | |
477 | and if you want to compress each file one at a time, this will do the trick |
478 | |
479 | use strict ; |
480 | use warnings ; |
481 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
482 | |
483 | for my $input ( glob "/my/home/*.txt.1950" ) |
484 | { |
485 | my $output = $input; |
486 | $output =~ s/.1950// ; |
487 | inflate $input => $output |
488 | or die "Error compressing '$input': $InflateError\n"; |
489 | } |
490 | |
491 | =head1 OO Interface |
492 | |
493 | =head2 Constructor |
494 | |
495 | The format of the constructor for IO::Uncompress::Inflate is shown below |
496 | |
497 | |
498 | my $z = new IO::Uncompress::Inflate $input [OPTS] |
499 | or die "IO::Uncompress::Inflate failed: $InflateError\n"; |
500 | |
501 | Returns an C<IO::Uncompress::Inflate> object on success and undef on failure. |
502 | The variable C<$InflateError> will contain an error message on failure. |
503 | |
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504 | If you are running Perl 5.005 or better the object, C<$z>, returned from |
505 | IO::Uncompress::Inflate can be used exactly like an L<IO::File|IO::File> filehandle. |
506 | This means that all normal input file operations can be carried out with |
507 | C<$z>. For example, to read a line from a compressed file/buffer you can |
508 | use either of these forms |
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509 | |
510 | $line = $z->getline(); |
511 | $line = <$z>; |
512 | |
513 | The mandatory parameter C<$input> is used to determine the source of the |
514 | compressed data. This parameter can take one of three forms. |
515 | |
516 | =over 5 |
517 | |
518 | =item A filename |
519 | |
520 | If the C<$input> parameter is a scalar, it is assumed to be a filename. This |
521 | file will be opened for reading and the compressed data will be read from it. |
522 | |
523 | =item A filehandle |
524 | |
525 | If the C<$input> parameter is a filehandle, the compressed data will be |
526 | read from it. |
527 | The string '-' can be used as an alias for standard input. |
528 | |
529 | |
530 | =item A scalar reference |
531 | |
532 | If C<$input> is a scalar reference, the compressed data will be read from |
533 | C<$$output>. |
534 | |
535 | =back |
536 | |
537 | =head2 Constructor Options |
538 | |
539 | |
540 | The option names defined below are case insensitive and can be optionally |
541 | prefixed by a '-'. So all of the following are valid |
542 | |
543 | -AutoClose |
544 | -autoclose |
545 | AUTOCLOSE |
546 | autoclose |
547 | |
548 | OPTS is a combination of the following options: |
549 | |
550 | =over 5 |
551 | |
552 | =item -AutoClose =E<gt> 0|1 |
553 | |
554 | This option is only valid when the C<$input> parameter is a filehandle. If |
555 | specified, and the value is true, it will result in the file being closed once |
556 | either the C<close> method is called or the IO::Uncompress::Inflate object is |
557 | destroyed. |
558 | |
559 | This parameter defaults to 0. |
560 | |
561 | =item -MultiStream =E<gt> 0|1 |
562 | |
563 | |
564 | |
565 | Allows multiple concatenated compressed streams to be treated as a single |
566 | compressed stream. Decompression will stop once either the end of the |
567 | file/buffer is reached, an error is encountered (premature eof, corrupt |
568 | compressed data) or the end of a stream is not immediately followed by the |
569 | start of another stream. |
570 | |
571 | This parameter defaults to 0. |
572 | |
573 | |
574 | |
575 | =item -Prime =E<gt> $string |
576 | |
577 | This option will uncompress the contents of C<$string> before processing the |
578 | input file/buffer. |
579 | |
580 | This option can be useful when the compressed data is embedded in another |
581 | file/data structure and it is not possible to work out where the compressed |
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582 | data begins without having to read the first few bytes. If this is the |
583 | case, the uncompression can be I<primed> with these bytes using this |
584 | option. |
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585 | |
586 | =item -Transparent =E<gt> 0|1 |
587 | |
588 | If this option is set and the input file or buffer is not compressed data, |
589 | the module will allow reading of it anyway. |
590 | |
591 | This option defaults to 1. |
592 | |
593 | =item -BlockSize =E<gt> $num |
594 | |
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595 | When reading the compressed input data, IO::Uncompress::Inflate will read it in |
596 | blocks of C<$num> bytes. |
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597 | |
598 | This option defaults to 4096. |
599 | |
600 | =item -InputLength =E<gt> $size |
601 | |
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602 | When present this option will limit the number of compressed bytes read |
603 | from the input file/buffer to C<$size>. This option can be used in the |
604 | situation where there is useful data directly after the compressed data |
605 | stream and you know beforehand the exact length of the compressed data |
606 | stream. |
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607 | |
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608 | This option is mostly used when reading from a filehandle, in which case |
609 | the file pointer will be left pointing to the first byte directly after the |
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610 | compressed data stream. |
611 | |
612 | |
613 | |
614 | This option defaults to off. |
615 | |
616 | =item -Append =E<gt> 0|1 |
617 | |
618 | This option controls what the C<read> method does with uncompressed data. |
619 | |
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620 | If set to 1, all uncompressed data will be appended to the output parameter |
621 | of the C<read> method. |
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622 | |
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623 | If set to 0, the contents of the output parameter of the C<read> method |
624 | will be overwritten by the uncompressed data. |
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625 | |
626 | Defaults to 0. |
627 | |
628 | =item -Strict =E<gt> 0|1 |
629 | |
630 | |
631 | |
632 | This option controls whether the extra checks defined below are used when |
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633 | carrying out the decompression. When Strict is on, the extra tests are |
634 | carried out, when Strict is off they are not. |
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635 | |
636 | The default for this option is off. |
637 | |
638 | |
639 | |
640 | |
641 | |
642 | =over 5 |
643 | |
644 | =item 1 |
645 | |
646 | The ADLER32 checksum field must be present. |
647 | |
648 | =item 2 |
649 | |
650 | The value of the ADLER32 field read must match the adler32 value of the |
651 | uncompressed data actually contained in the file. |
652 | |
653 | =back |
654 | |
655 | |
656 | |
657 | |
658 | |
659 | |
660 | |
661 | |
662 | |
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663 | |
664 | |
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665 | =back |
666 | |
667 | =head2 Examples |
668 | |
669 | TODO |
670 | |
671 | =head1 Methods |
672 | |
673 | =head2 read |
674 | |
675 | Usage is |
676 | |
677 | $status = $z->read($buffer) |
678 | |
679 | Reads a block of compressed data (the size the the compressed block is |
680 | determined by the C<Buffer> option in the constructor), uncompresses it and |
1a6a8453 |
681 | writes any uncompressed data into C<$buffer>. If the C<Append> parameter is |
682 | set in the constructor, the uncompressed data will be appended to the |
683 | C<$buffer> parameter. Otherwise C<$buffer> will be overwritten. |
642e522c |
684 | |
1a6a8453 |
685 | Returns the number of uncompressed bytes written to C<$buffer>, zero if eof |
686 | or a negative number on error. |
642e522c |
687 | |
688 | =head2 read |
689 | |
690 | Usage is |
691 | |
692 | $status = $z->read($buffer, $length) |
693 | $status = $z->read($buffer, $length, $offset) |
694 | |
695 | $status = read($z, $buffer, $length) |
696 | $status = read($z, $buffer, $length, $offset) |
697 | |
698 | Attempt to read C<$length> bytes of uncompressed data into C<$buffer>. |
699 | |
1a6a8453 |
700 | The main difference between this form of the C<read> method and the |
701 | previous one, is that this one will attempt to return I<exactly> C<$length> |
702 | bytes. The only circumstances that this function will not is if end-of-file |
703 | or an IO error is encountered. |
642e522c |
704 | |
1a6a8453 |
705 | Returns the number of uncompressed bytes written to C<$buffer>, zero if eof |
706 | or a negative number on error. |
642e522c |
707 | |
708 | |
709 | =head2 getline |
710 | |
711 | Usage is |
712 | |
713 | $line = $z->getline() |
714 | $line = <$z> |
715 | |
716 | Reads a single line. |
717 | |
718 | This method fully supports the use of of the variable C<$/> |
719 | (or C<$INPUT_RECORD_SEPARATOR> or C<$RS> when C<English> is in use) to |
720 | determine what constitutes an end of line. Both paragraph mode and file |
721 | slurp mode are supported. |
722 | |
723 | |
724 | =head2 getc |
725 | |
726 | Usage is |
727 | |
728 | $char = $z->getc() |
729 | |
730 | Read a single character. |
731 | |
732 | =head2 ungetc |
733 | |
734 | Usage is |
735 | |
736 | $char = $z->ungetc($string) |
737 | |
738 | |
a02d0f6f |
739 | |
642e522c |
740 | =head2 inflateSync |
741 | |
742 | Usage is |
743 | |
744 | $status = $z->inflateSync() |
745 | |
746 | TODO |
747 | |
a02d0f6f |
748 | |
642e522c |
749 | =head2 getHeaderInfo |
750 | |
751 | Usage is |
752 | |
1a6a8453 |
753 | $hdr = $z->getHeaderInfo(); |
754 | @hdrs = $z->getHeaderInfo(); |
642e522c |
755 | |
1a6a8453 |
756 | This method returns either a hash reference (in scalar context) or a list |
757 | or hash references (in array context) that contains information about each |
758 | of the header fields in the compressed data stream(s). |
642e522c |
759 | |
760 | |
761 | |
762 | |
763 | =head2 tell |
764 | |
765 | Usage is |
766 | |
767 | $z->tell() |
768 | tell $z |
769 | |
770 | Returns the uncompressed file offset. |
771 | |
772 | =head2 eof |
773 | |
774 | Usage is |
775 | |
776 | $z->eof(); |
777 | eof($z); |
778 | |
779 | |
780 | |
781 | Returns true if the end of the compressed input stream has been reached. |
782 | |
783 | |
784 | |
785 | =head2 seek |
786 | |
787 | $z->seek($position, $whence); |
788 | seek($z, $position, $whence); |
789 | |
790 | |
791 | |
792 | |
793 | Provides a sub-set of the C<seek> functionality, with the restriction |
794 | that it is only legal to seek forward in the input file/buffer. |
795 | It is a fatal error to attempt to seek backward. |
796 | |
797 | |
798 | |
799 | The C<$whence> parameter takes one the usual values, namely SEEK_SET, |
800 | SEEK_CUR or SEEK_END. |
801 | |
802 | Returns 1 on success, 0 on failure. |
803 | |
804 | =head2 binmode |
805 | |
806 | Usage is |
807 | |
808 | $z->binmode |
809 | binmode $z ; |
810 | |
811 | This is a noop provided for completeness. |
812 | |
a02d0f6f |
813 | =head2 opened |
814 | |
815 | $z->opened() |
816 | |
817 | Returns true if the object currently refers to a opened file/buffer. |
818 | |
819 | =head2 autoflush |
820 | |
821 | my $prev = $z->autoflush() |
822 | my $prev = $z->autoflush(EXPR) |
823 | |
824 | If the C<$z> object is associated with a file or a filehandle, this method |
825 | returns the current autoflush setting for the underlying filehandle. If |
826 | C<EXPR> is present, and is non-zero, it will enable flushing after every |
827 | write/print operation. |
828 | |
829 | If C<$z> is associated with a buffer, this method has no effect and always |
830 | returns C<undef>. |
831 | |
832 | B<Note> that the special variable C<$|> B<cannot> be used to set or |
833 | retrieve the autoflush setting. |
834 | |
835 | =head2 input_line_number |
836 | |
837 | $z->input_line_number() |
838 | $z->input_line_number(EXPR) |
839 | |
840 | |
841 | |
842 | Returns the current uncompressed line number. If C<EXPR> is present it has |
843 | the effect of setting the line number. Note that setting the line number |
844 | does not change the current position within the file/buffer being read. |
845 | |
846 | The contents of C<$/> are used to to determine what constitutes a line |
847 | terminator. |
848 | |
849 | |
850 | |
642e522c |
851 | =head2 fileno |
852 | |
853 | $z->fileno() |
854 | fileno($z) |
855 | |
a02d0f6f |
856 | If the C<$z> object is associated with a file or a filehandle, this method |
857 | will return the underlying file descriptor. |
642e522c |
858 | |
859 | If the C<$z> object is is associated with a buffer, this method will |
860 | return undef. |
861 | |
862 | =head2 close |
863 | |
864 | $z->close() ; |
865 | close $z ; |
866 | |
867 | |
868 | |
869 | Closes the output file/buffer. |
870 | |
871 | |
872 | |
873 | For most versions of Perl this method will be automatically invoked if |
874 | the IO::Uncompress::Inflate object is destroyed (either explicitly or by the |
875 | variable with the reference to the object going out of scope). The |
876 | exceptions are Perl versions 5.005 through 5.00504 and 5.8.0. In |
877 | these cases, the C<close> method will be called automatically, but |
878 | not until global destruction of all live objects when the program is |
879 | terminating. |
880 | |
881 | Therefore, if you want your scripts to be able to run on all versions |
882 | of Perl, you should call C<close> explicitly and not rely on automatic |
883 | closing. |
884 | |
885 | Returns true on success, otherwise 0. |
886 | |
887 | If the C<AutoClose> option has been enabled when the IO::Uncompress::Inflate |
888 | object was created, and the object is associated with a file, the |
889 | underlying file will also be closed. |
890 | |
891 | |
892 | |
893 | |
894 | =head1 Importing |
895 | |
896 | No symbolic constants are required by this IO::Uncompress::Inflate at present. |
897 | |
898 | =over 5 |
899 | |
900 | =item :all |
901 | |
902 | Imports C<inflate> and C<$InflateError>. |
903 | Same as doing this |
904 | |
905 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
906 | |
907 | =back |
908 | |
909 | =head1 EXAMPLES |
910 | |
911 | |
912 | |
913 | |
914 | =head1 SEE ALSO |
915 | |
a02d0f6f |
916 | L<Compress::Zlib>, L<IO::Compress::Gzip>, L<IO::Uncompress::Gunzip>, L<IO::Compress::Deflate>, L<IO::Compress::RawDeflate>, L<IO::Uncompress::RawInflate>, L<IO::Compress::Bzip2>, L<IO::Uncompress::Bunzip2>, L<IO::Compress::Lzop>, L<IO::Uncompress::UnLzop>, L<IO::Uncompress::AnyInflate>, L<IO::Uncompress::AnyUncompress> |
642e522c |
917 | |
918 | L<Compress::Zlib::FAQ|Compress::Zlib::FAQ> |
919 | |
a02d0f6f |
920 | L<File::GlobMapper|File::GlobMapper>, L<Archive::Zip|Archive::Zip>, |
921 | L<Archive::Tar|Archive::Tar>, |
642e522c |
922 | L<IO::Zlib|IO::Zlib> |
923 | |
a02d0f6f |
924 | |
642e522c |
925 | For RFC 1950, 1951 and 1952 see |
926 | F<http://www.faqs.org/rfcs/rfc1950.html>, |
927 | F<http://www.faqs.org/rfcs/rfc1951.html> and |
928 | F<http://www.faqs.org/rfcs/rfc1952.html> |
929 | |
a02d0f6f |
930 | The I<zlib> compression library was written by Jean-loup Gailly |
931 | F<gzip@prep.ai.mit.edu> and Mark Adler F<madler@alumni.caltech.edu>. |
932 | |
933 | The primary site for the I<zlib> compression library is |
934 | F<http://www.zlib.org>. |
935 | |
936 | The primary site for gzip is F<http://www.gzip.org>. |
937 | |
938 | |
939 | |
940 | |
941 | |
942 | |
642e522c |
943 | |
944 | =head1 AUTHOR |
945 | |
946 | The I<IO::Uncompress::Inflate> module was written by Paul Marquess, |
a02d0f6f |
947 | F<pmqs@cpan.org>. |
642e522c |
948 | |
642e522c |
949 | |
642e522c |
950 | |
951 | =head1 MODIFICATION HISTORY |
952 | |
953 | See the Changes file. |
954 | |
955 | =head1 COPYRIGHT AND LICENSE |
956 | |
957 | |
1a6a8453 |
958 | Copyright (c) 2005-2006 Paul Marquess. All rights reserved. |
a02d0f6f |
959 | |
642e522c |
960 | This program is free software; you can redistribute it and/or |
961 | modify it under the same terms as Perl itself. |
962 | |