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_13'; |
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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 | |
182 | IO::Uncompress::Inflate - Read RFC 1950 files/buffers |
183 | |
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184 | |
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185 | |
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186 | =head1 SYNOPSIS |
187 | |
188 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
189 | |
190 | my $status = inflate $input => $output [,OPTS] |
191 | or die "inflate failed: $InflateError\n"; |
192 | |
193 | my $z = new IO::Uncompress::Inflate $input [OPTS] |
194 | or die "inflate failed: $InflateError\n"; |
195 | |
196 | $status = $z->read($buffer) |
197 | $status = $z->read($buffer, $length) |
198 | $status = $z->read($buffer, $length, $offset) |
199 | $line = $z->getline() |
200 | $char = $z->getc() |
201 | $char = $z->ungetc() |
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202 | $char = $z->opened() |
203 | |
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204 | $status = $z->inflateSync() |
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205 | |
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206 | $data = $z->trailingData() |
207 | $status = $z->nextStream() |
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208 | $data = $z->getHeaderInfo() |
209 | $z->tell() |
210 | $z->seek($position, $whence) |
211 | $z->binmode() |
212 | $z->fileno() |
213 | $z->eof() |
214 | $z->close() |
215 | |
216 | $InflateError ; |
217 | |
218 | # IO::File mode |
219 | |
220 | <$z> |
221 | read($z, $buffer); |
222 | read($z, $buffer, $length); |
223 | read($z, $buffer, $length, $offset); |
224 | tell($z) |
225 | seek($z, $position, $whence) |
226 | binmode($z) |
227 | fileno($z) |
228 | eof($z) |
229 | close($z) |
230 | |
231 | |
232 | =head1 DESCRIPTION |
233 | |
234 | |
235 | |
236 | B<WARNING -- This is a Beta release>. |
237 | |
238 | =over 5 |
239 | |
240 | =item * DO NOT use in production code. |
241 | |
242 | =item * The documentation is incomplete in places. |
243 | |
244 | =item * Parts of the interface defined here are tentative. |
245 | |
246 | =item * Please report any problems you find. |
247 | |
248 | =back |
249 | |
250 | |
251 | |
252 | |
253 | |
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254 | This module provides a Perl interface that allows the reading of |
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255 | files/buffers that conform to RFC 1950. |
256 | |
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257 | For writing RFC 1950 files/buffers, see the companion module IO::Compress::Deflate. |
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258 | |
259 | |
260 | |
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261 | |
262 | |
263 | |
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264 | =head1 Functional Interface |
265 | |
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266 | A top-level function, C<inflate>, is provided to carry out |
267 | "one-shot" uncompression between buffers and/or files. For finer |
268 | control over the uncompression process, see the L</"OO Interface"> |
269 | section. |
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270 | |
271 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
272 | |
273 | inflate $input => $output [,OPTS] |
274 | or die "inflate failed: $InflateError\n"; |
275 | |
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276 | |
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277 | |
278 | The functional interface needs Perl5.005 or better. |
279 | |
280 | |
281 | =head2 inflate $input => $output [, OPTS] |
282 | |
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283 | |
284 | C<inflate> expects at least two parameters, C<$input> and C<$output>. |
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285 | |
286 | =head3 The C<$input> parameter |
287 | |
288 | The parameter, C<$input>, is used to define the source of |
289 | the compressed data. |
290 | |
291 | It can take one of the following forms: |
292 | |
293 | =over 5 |
294 | |
295 | =item A filename |
296 | |
297 | If the C<$input> parameter is a simple scalar, it is assumed to be a |
298 | filename. This file will be opened for reading and the input data |
299 | will be read from it. |
300 | |
301 | =item A filehandle |
302 | |
303 | If the C<$input> parameter is a filehandle, the input data will be |
304 | read from it. |
305 | The string '-' can be used as an alias for standard input. |
306 | |
307 | =item A scalar reference |
308 | |
309 | If C<$input> is a scalar reference, the input data will be read |
310 | from C<$$input>. |
311 | |
312 | =item An array reference |
313 | |
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314 | If C<$input> is an array reference, each element in the array must be a |
315 | filename. |
316 | |
317 | The input data will be read from each file in turn. |
318 | |
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319 | The complete array will be walked to ensure that it only |
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320 | contains valid filenames before any data is uncompressed. |
321 | |
322 | |
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323 | |
324 | =item An Input FileGlob string |
325 | |
326 | If C<$input> is a string that is delimited by the characters "<" and ">" |
327 | C<inflate> will assume that it is an I<input fileglob string>. The |
328 | input is the list of files that match the fileglob. |
329 | |
330 | If the fileglob does not match any files ... |
331 | |
332 | See L<File::GlobMapper|File::GlobMapper> for more details. |
333 | |
334 | |
335 | =back |
336 | |
337 | If the C<$input> parameter is any other type, C<undef> will be returned. |
338 | |
339 | |
340 | |
341 | =head3 The C<$output> parameter |
342 | |
343 | The parameter C<$output> is used to control the destination of the |
344 | uncompressed data. This parameter can take one of these forms. |
345 | |
346 | =over 5 |
347 | |
348 | =item A filename |
349 | |
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350 | If the C<$output> parameter is a simple scalar, it is assumed to be a |
351 | filename. This file will be opened for writing and the uncompressed |
352 | data will be written to it. |
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353 | |
354 | =item A filehandle |
355 | |
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356 | If the C<$output> parameter is a filehandle, the uncompressed data |
357 | will be written to it. |
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358 | The string '-' can be used as an alias for standard output. |
359 | |
360 | |
361 | =item A scalar reference |
362 | |
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363 | If C<$output> is a scalar reference, the uncompressed data will be |
364 | stored in C<$$output>. |
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365 | |
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366 | |
367 | |
368 | =item An Array Reference |
369 | |
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370 | If C<$output> is an array reference, the uncompressed data will be |
371 | pushed onto the array. |
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372 | |
373 | =item An Output FileGlob |
374 | |
375 | If C<$output> is a string that is delimited by the characters "<" and ">" |
376 | C<inflate> will assume that it is an I<output fileglob string>. The |
377 | output is the list of files that match the fileglob. |
378 | |
379 | When C<$output> is an fileglob string, C<$input> must also be a fileglob |
380 | string. Anything else is an error. |
381 | |
382 | =back |
383 | |
384 | If the C<$output> parameter is any other type, C<undef> will be returned. |
385 | |
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386 | |
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387 | |
388 | =head2 Notes |
389 | |
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390 | |
391 | When C<$input> maps to multiple compressed files/buffers and C<$output> is |
392 | a single file/buffer, after uncompression C<$output> will contain a |
393 | concatenation of all the uncompressed data from each of the input |
394 | files/buffers. |
395 | |
396 | |
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397 | |
398 | |
399 | |
400 | =head2 Optional Parameters |
401 | |
402 | Unless specified below, the optional parameters for C<inflate>, |
403 | C<OPTS>, are the same as those used with the OO interface defined in the |
404 | L</"Constructor Options"> section below. |
405 | |
406 | =over 5 |
407 | |
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408 | =item C<< AutoClose => 0|1 >> |
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409 | |
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410 | This option applies to any input or output data streams to |
411 | C<inflate> that are filehandles. |
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412 | |
413 | If C<AutoClose> is specified, and the value is true, it will result in all |
414 | input and/or output filehandles being closed once C<inflate> has |
415 | completed. |
416 | |
417 | This parameter defaults to 0. |
418 | |
419 | |
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420 | =item C<< BinModeOut => 0|1 >> |
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421 | |
422 | When writing to a file or filehandle, set C<binmode> before writing to the |
423 | file. |
424 | |
425 | Defaults to 0. |
426 | |
427 | |
428 | |
429 | |
430 | |
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431 | =item C<< Append => 0|1 >> |
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432 | |
433 | TODO |
434 | |
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435 | =item C<< MultiStream => 0|1 >> |
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436 | |
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437 | If the input file/buffer contains multiple compressed data streams, this |
438 | option will uncompress the whole lot as a single data stream. |
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439 | |
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440 | Defaults to 0. |
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441 | |
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442 | |
443 | |
444 | =back |
445 | |
446 | |
447 | |
448 | |
449 | =head2 Examples |
450 | |
451 | To read the contents of the file C<file1.txt.1950> and write the |
452 | compressed data to the file C<file1.txt>. |
453 | |
454 | use strict ; |
455 | use warnings ; |
456 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
457 | |
458 | my $input = "file1.txt.1950"; |
459 | my $output = "file1.txt"; |
460 | inflate $input => $output |
461 | or die "inflate failed: $InflateError\n"; |
462 | |
463 | |
464 | To read from an existing Perl filehandle, C<$input>, and write the |
465 | uncompressed data to a buffer, C<$buffer>. |
466 | |
467 | use strict ; |
468 | use warnings ; |
469 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
470 | use IO::File ; |
471 | |
472 | my $input = new IO::File "<file1.txt.1950" |
473 | or die "Cannot open 'file1.txt.1950': $!\n" ; |
474 | my $buffer ; |
475 | inflate $input => \$buffer |
476 | or die "inflate failed: $InflateError\n"; |
477 | |
478 | To uncompress all files in the directory "/my/home" that match "*.txt.1950" and store the compressed data in the same directory |
479 | |
480 | use strict ; |
481 | use warnings ; |
482 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
483 | |
484 | inflate '</my/home/*.txt.1950>' => '</my/home/#1.txt>' |
485 | or die "inflate failed: $InflateError\n"; |
486 | |
487 | and if you want to compress each file one at a time, this will do the trick |
488 | |
489 | use strict ; |
490 | use warnings ; |
491 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
492 | |
493 | for my $input ( glob "/my/home/*.txt.1950" ) |
494 | { |
495 | my $output = $input; |
496 | $output =~ s/.1950// ; |
497 | inflate $input => $output |
498 | or die "Error compressing '$input': $InflateError\n"; |
499 | } |
500 | |
501 | =head1 OO Interface |
502 | |
503 | =head2 Constructor |
504 | |
505 | The format of the constructor for IO::Uncompress::Inflate is shown below |
506 | |
507 | |
508 | my $z = new IO::Uncompress::Inflate $input [OPTS] |
509 | or die "IO::Uncompress::Inflate failed: $InflateError\n"; |
510 | |
511 | Returns an C<IO::Uncompress::Inflate> object on success and undef on failure. |
512 | The variable C<$InflateError> will contain an error message on failure. |
513 | |
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514 | If you are running Perl 5.005 or better the object, C<$z>, returned from |
515 | IO::Uncompress::Inflate can be used exactly like an L<IO::File|IO::File> filehandle. |
516 | This means that all normal input file operations can be carried out with |
517 | C<$z>. For example, to read a line from a compressed file/buffer you can |
518 | use either of these forms |
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519 | |
520 | $line = $z->getline(); |
521 | $line = <$z>; |
522 | |
523 | The mandatory parameter C<$input> is used to determine the source of the |
524 | compressed data. This parameter can take one of three forms. |
525 | |
526 | =over 5 |
527 | |
528 | =item A filename |
529 | |
530 | If the C<$input> parameter is a scalar, it is assumed to be a filename. This |
531 | file will be opened for reading and the compressed data will be read from it. |
532 | |
533 | =item A filehandle |
534 | |
535 | If the C<$input> parameter is a filehandle, the compressed data will be |
536 | read from it. |
537 | The string '-' can be used as an alias for standard input. |
538 | |
539 | |
540 | =item A scalar reference |
541 | |
542 | If C<$input> is a scalar reference, the compressed data will be read from |
543 | C<$$output>. |
544 | |
545 | =back |
546 | |
547 | =head2 Constructor Options |
548 | |
549 | |
550 | The option names defined below are case insensitive and can be optionally |
551 | prefixed by a '-'. So all of the following are valid |
552 | |
553 | -AutoClose |
554 | -autoclose |
555 | AUTOCLOSE |
556 | autoclose |
557 | |
558 | OPTS is a combination of the following options: |
559 | |
560 | =over 5 |
561 | |
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562 | =item C<< AutoClose => 0|1 >> |
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563 | |
564 | This option is only valid when the C<$input> parameter is a filehandle. If |
565 | specified, and the value is true, it will result in the file being closed once |
566 | either the C<close> method is called or the IO::Uncompress::Inflate object is |
567 | destroyed. |
568 | |
569 | This parameter defaults to 0. |
570 | |
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571 | =item C<< MultiStream => 0|1 >> |
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572 | |
573 | |
574 | |
575 | Allows multiple concatenated compressed streams to be treated as a single |
576 | compressed stream. Decompression will stop once either the end of the |
577 | file/buffer is reached, an error is encountered (premature eof, corrupt |
578 | compressed data) or the end of a stream is not immediately followed by the |
579 | start of another stream. |
580 | |
581 | This parameter defaults to 0. |
582 | |
583 | |
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584 | =item C<< Prime => $string >> |
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585 | |
586 | This option will uncompress the contents of C<$string> before processing the |
587 | input file/buffer. |
588 | |
589 | This option can be useful when the compressed data is embedded in another |
590 | file/data structure and it is not possible to work out where the compressed |
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591 | data begins without having to read the first few bytes. If this is the |
592 | case, the uncompression can be I<primed> with these bytes using this |
593 | option. |
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594 | |
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595 | =item C<< Transparent => 0|1 >> |
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596 | |
597 | If this option is set and the input file or buffer is not compressed data, |
598 | the module will allow reading of it anyway. |
599 | |
600 | This option defaults to 1. |
601 | |
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602 | =item C<< BlockSize => $num >> |
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603 | |
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604 | When reading the compressed input data, IO::Uncompress::Inflate will read it in |
605 | blocks of C<$num> bytes. |
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606 | |
607 | This option defaults to 4096. |
608 | |
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609 | =item C<< InputLength => $size >> |
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610 | |
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611 | When present this option will limit the number of compressed bytes read |
612 | from the input file/buffer to C<$size>. This option can be used in the |
613 | situation where there is useful data directly after the compressed data |
614 | stream and you know beforehand the exact length of the compressed data |
615 | stream. |
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616 | |
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617 | This option is mostly used when reading from a filehandle, in which case |
618 | the file pointer will be left pointing to the first byte directly after the |
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619 | compressed data stream. |
620 | |
621 | |
622 | |
623 | This option defaults to off. |
624 | |
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625 | =item C<< Append => 0|1 >> |
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626 | |
627 | This option controls what the C<read> method does with uncompressed data. |
628 | |
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629 | If set to 1, all uncompressed data will be appended to the output parameter |
630 | of the C<read> method. |
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631 | |
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632 | If set to 0, the contents of the output parameter of the C<read> method |
633 | will be overwritten by the uncompressed data. |
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634 | |
635 | Defaults to 0. |
636 | |
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637 | =item C<< Strict => 0|1 >> |
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638 | |
639 | |
640 | |
641 | This option controls whether the extra checks defined below are used when |
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642 | carrying out the decompression. When Strict is on, the extra tests are |
643 | carried out, when Strict is off they are not. |
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644 | |
645 | The default for this option is off. |
646 | |
647 | |
648 | |
649 | |
650 | |
651 | =over 5 |
652 | |
653 | =item 1 |
654 | |
655 | The ADLER32 checksum field must be present. |
656 | |
657 | =item 2 |
658 | |
659 | The value of the ADLER32 field read must match the adler32 value of the |
660 | uncompressed data actually contained in the file. |
661 | |
662 | =back |
663 | |
664 | |
665 | |
666 | |
667 | |
668 | |
669 | |
670 | |
671 | |
a02d0f6f |
672 | |
673 | |
642e522c |
674 | =back |
675 | |
676 | =head2 Examples |
677 | |
678 | TODO |
679 | |
680 | =head1 Methods |
681 | |
682 | =head2 read |
683 | |
684 | Usage is |
685 | |
686 | $status = $z->read($buffer) |
687 | |
688 | Reads a block of compressed data (the size the the compressed block is |
689 | determined by the C<Buffer> option in the constructor), uncompresses it and |
1a6a8453 |
690 | writes any uncompressed data into C<$buffer>. If the C<Append> parameter is |
691 | set in the constructor, the uncompressed data will be appended to the |
692 | C<$buffer> parameter. Otherwise C<$buffer> will be overwritten. |
642e522c |
693 | |
1a6a8453 |
694 | Returns the number of uncompressed bytes written to C<$buffer>, zero if eof |
695 | or a negative number on error. |
642e522c |
696 | |
697 | =head2 read |
698 | |
699 | Usage is |
700 | |
701 | $status = $z->read($buffer, $length) |
702 | $status = $z->read($buffer, $length, $offset) |
703 | |
704 | $status = read($z, $buffer, $length) |
705 | $status = read($z, $buffer, $length, $offset) |
706 | |
707 | Attempt to read C<$length> bytes of uncompressed data into C<$buffer>. |
708 | |
1a6a8453 |
709 | The main difference between this form of the C<read> method and the |
710 | previous one, is that this one will attempt to return I<exactly> C<$length> |
711 | bytes. The only circumstances that this function will not is if end-of-file |
712 | or an IO error is encountered. |
642e522c |
713 | |
1a6a8453 |
714 | Returns the number of uncompressed bytes written to C<$buffer>, zero if eof |
715 | or a negative number on error. |
642e522c |
716 | |
717 | |
718 | =head2 getline |
719 | |
720 | Usage is |
721 | |
722 | $line = $z->getline() |
723 | $line = <$z> |
724 | |
725 | Reads a single line. |
726 | |
727 | This method fully supports the use of of the variable C<$/> |
728 | (or C<$INPUT_RECORD_SEPARATOR> or C<$RS> when C<English> is in use) to |
729 | determine what constitutes an end of line. Both paragraph mode and file |
730 | slurp mode are supported. |
731 | |
732 | |
733 | =head2 getc |
734 | |
735 | Usage is |
736 | |
737 | $char = $z->getc() |
738 | |
739 | Read a single character. |
740 | |
741 | =head2 ungetc |
742 | |
743 | Usage is |
744 | |
745 | $char = $z->ungetc($string) |
746 | |
747 | |
a02d0f6f |
748 | |
642e522c |
749 | =head2 inflateSync |
750 | |
751 | Usage is |
752 | |
753 | $status = $z->inflateSync() |
754 | |
755 | TODO |
756 | |
a02d0f6f |
757 | |
642e522c |
758 | =head2 getHeaderInfo |
759 | |
760 | Usage is |
761 | |
1a6a8453 |
762 | $hdr = $z->getHeaderInfo(); |
763 | @hdrs = $z->getHeaderInfo(); |
642e522c |
764 | |
1a6a8453 |
765 | This method returns either a hash reference (in scalar context) or a list |
766 | or hash references (in array context) that contains information about each |
767 | of the header fields in the compressed data stream(s). |
642e522c |
768 | |
769 | |
770 | |
771 | |
772 | =head2 tell |
773 | |
774 | Usage is |
775 | |
776 | $z->tell() |
777 | tell $z |
778 | |
779 | Returns the uncompressed file offset. |
780 | |
781 | =head2 eof |
782 | |
783 | Usage is |
784 | |
785 | $z->eof(); |
786 | eof($z); |
787 | |
788 | |
789 | |
790 | Returns true if the end of the compressed input stream has been reached. |
791 | |
792 | |
793 | |
794 | =head2 seek |
795 | |
796 | $z->seek($position, $whence); |
797 | seek($z, $position, $whence); |
798 | |
799 | |
800 | |
801 | |
802 | Provides a sub-set of the C<seek> functionality, with the restriction |
803 | that it is only legal to seek forward in the input file/buffer. |
804 | It is a fatal error to attempt to seek backward. |
805 | |
806 | |
807 | |
808 | The C<$whence> parameter takes one the usual values, namely SEEK_SET, |
809 | SEEK_CUR or SEEK_END. |
810 | |
811 | Returns 1 on success, 0 on failure. |
812 | |
813 | =head2 binmode |
814 | |
815 | Usage is |
816 | |
817 | $z->binmode |
818 | binmode $z ; |
819 | |
820 | This is a noop provided for completeness. |
821 | |
a02d0f6f |
822 | =head2 opened |
823 | |
824 | $z->opened() |
825 | |
826 | Returns true if the object currently refers to a opened file/buffer. |
827 | |
828 | =head2 autoflush |
829 | |
830 | my $prev = $z->autoflush() |
831 | my $prev = $z->autoflush(EXPR) |
832 | |
833 | If the C<$z> object is associated with a file or a filehandle, this method |
834 | returns the current autoflush setting for the underlying filehandle. If |
835 | C<EXPR> is present, and is non-zero, it will enable flushing after every |
836 | write/print operation. |
837 | |
838 | If C<$z> is associated with a buffer, this method has no effect and always |
839 | returns C<undef>. |
840 | |
841 | B<Note> that the special variable C<$|> B<cannot> be used to set or |
842 | retrieve the autoflush setting. |
843 | |
844 | =head2 input_line_number |
845 | |
846 | $z->input_line_number() |
847 | $z->input_line_number(EXPR) |
848 | |
849 | |
850 | |
851 | Returns the current uncompressed line number. If C<EXPR> is present it has |
852 | the effect of setting the line number. Note that setting the line number |
853 | does not change the current position within the file/buffer being read. |
854 | |
855 | The contents of C<$/> are used to to determine what constitutes a line |
856 | terminator. |
857 | |
858 | |
859 | |
642e522c |
860 | =head2 fileno |
861 | |
862 | $z->fileno() |
863 | fileno($z) |
864 | |
a02d0f6f |
865 | If the C<$z> object is associated with a file or a filehandle, this method |
866 | will return the underlying file descriptor. |
642e522c |
867 | |
868 | If the C<$z> object is is associated with a buffer, this method will |
869 | return undef. |
870 | |
871 | =head2 close |
872 | |
873 | $z->close() ; |
874 | close $z ; |
875 | |
876 | |
877 | |
878 | Closes the output file/buffer. |
879 | |
880 | |
881 | |
882 | For most versions of Perl this method will be automatically invoked if |
883 | the IO::Uncompress::Inflate object is destroyed (either explicitly or by the |
884 | variable with the reference to the object going out of scope). The |
885 | exceptions are Perl versions 5.005 through 5.00504 and 5.8.0. In |
886 | these cases, the C<close> method will be called automatically, but |
887 | not until global destruction of all live objects when the program is |
888 | terminating. |
889 | |
890 | Therefore, if you want your scripts to be able to run on all versions |
891 | of Perl, you should call C<close> explicitly and not rely on automatic |
892 | closing. |
893 | |
894 | Returns true on success, otherwise 0. |
895 | |
896 | If the C<AutoClose> option has been enabled when the IO::Uncompress::Inflate |
897 | object was created, and the object is associated with a file, the |
898 | underlying file will also be closed. |
899 | |
900 | |
901 | |
902 | |
e7d45986 |
903 | =head2 nextStream |
904 | |
905 | Usage is |
906 | |
907 | my $status = $z->nextStream(); |
908 | |
909 | Skips to the next compressed data stream in the input file/buffer. If a new |
910 | compressed data stream is found, the eof marker will be cleared, C<$.> will |
911 | be reset to 0. |
912 | |
913 | Returns 1 if a new stream was found, 0 if none was found, and -1 if an |
914 | error was encountered. |
915 | |
916 | =head2 trailingData |
917 | |
918 | Usage is |
919 | |
920 | my $data = $z->trailingData(); |
921 | |
922 | Returns any data that |
923 | |
642e522c |
924 | =head1 Importing |
925 | |
926 | No symbolic constants are required by this IO::Uncompress::Inflate at present. |
927 | |
928 | =over 5 |
929 | |
930 | =item :all |
931 | |
932 | Imports C<inflate> and C<$InflateError>. |
933 | Same as doing this |
934 | |
935 | use IO::Uncompress::Inflate qw(inflate $InflateError) ; |
936 | |
937 | =back |
938 | |
939 | =head1 EXAMPLES |
940 | |
941 | |
942 | |
943 | |
944 | =head1 SEE ALSO |
945 | |
a02d0f6f |
946 | 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 |
947 | |
948 | L<Compress::Zlib::FAQ|Compress::Zlib::FAQ> |
949 | |
a02d0f6f |
950 | L<File::GlobMapper|File::GlobMapper>, L<Archive::Zip|Archive::Zip>, |
951 | L<Archive::Tar|Archive::Tar>, |
642e522c |
952 | L<IO::Zlib|IO::Zlib> |
953 | |
a02d0f6f |
954 | |
642e522c |
955 | For RFC 1950, 1951 and 1952 see |
956 | F<http://www.faqs.org/rfcs/rfc1950.html>, |
957 | F<http://www.faqs.org/rfcs/rfc1951.html> and |
958 | F<http://www.faqs.org/rfcs/rfc1952.html> |
959 | |
a02d0f6f |
960 | The I<zlib> compression library was written by Jean-loup Gailly |
961 | F<gzip@prep.ai.mit.edu> and Mark Adler F<madler@alumni.caltech.edu>. |
962 | |
963 | The primary site for the I<zlib> compression library is |
964 | F<http://www.zlib.org>. |
965 | |
966 | The primary site for gzip is F<http://www.gzip.org>. |
967 | |
968 | |
969 | |
970 | |
642e522c |
971 | =head1 AUTHOR |
972 | |
cb7abd7f |
973 | This module was written by Paul Marquess, F<pmqs@cpan.org>. |
642e522c |
974 | |
642e522c |
975 | |
642e522c |
976 | |
977 | =head1 MODIFICATION HISTORY |
978 | |
979 | See the Changes file. |
980 | |
981 | =head1 COPYRIGHT AND LICENSE |
642e522c |
982 | |
1a6a8453 |
983 | Copyright (c) 2005-2006 Paul Marquess. All rights reserved. |
a02d0f6f |
984 | |
642e522c |
985 | This program is free software; you can redistribute it and/or |
986 | modify it under the same terms as Perl itself. |
987 | |