Commit | Line | Data |
---|---|---|
642e522c RGS |
1 | |
2 | package IO::Uncompress::Gunzip ; | |
3 | ||
4 | require 5.004 ; | |
5 | ||
6 | # for RFC1952 | |
7 | ||
8 | use strict ; | |
9 | use warnings; | |
a02d0f6f | 10 | use bytes; |
642e522c | 11 | |
1a6a8453 PM |
12 | use IO::Uncompress::RawInflate ; |
13 | ||
a02d0f6f RGS |
14 | use Compress::Raw::Zlib qw( crc32 ) ; |
15 | use IO::Compress::Base::Common qw(:Status createSelfTiedObject); | |
16 | use IO::Compress::Gzip::Constants; | |
1a6a8453 | 17 | |
642e522c RGS |
18 | require Exporter ; |
19 | ||
20 | our ($VERSION, @ISA, @EXPORT_OK, %EXPORT_TAGS, $GunzipError); | |
21 | ||
1a6a8453 | 22 | @ISA = qw( Exporter IO::Uncompress::RawInflate ); |
642e522c | 23 | @EXPORT_OK = qw( $GunzipError gunzip ); |
1a6a8453 | 24 | %EXPORT_TAGS = %IO::Uncompress::RawInflate::DEFLATE_CONSTANTS ; |
642e522c RGS |
25 | push @{ $EXPORT_TAGS{all} }, @EXPORT_OK ; |
26 | Exporter::export_ok_tags('all'); | |
27 | ||
642e522c RGS |
28 | $GunzipError = ''; |
29 | ||
a02d0f6f | 30 | $VERSION = '2.000_08'; |
642e522c | 31 | |
1a6a8453 | 32 | sub new |
642e522c | 33 | { |
1a6a8453 PM |
34 | my $class = shift ; |
35 | $GunzipError = ''; | |
36 | my $obj = createSelfTiedObject($class, \$GunzipError); | |
642e522c | 37 | |
1a6a8453 | 38 | $obj->_create(undef, 0, @_); |
642e522c RGS |
39 | } |
40 | ||
1a6a8453 | 41 | sub gunzip |
642e522c | 42 | { |
1a6a8453 PM |
43 | my $obj = createSelfTiedObject(undef, \$GunzipError); |
44 | return $obj->_inf(@_) ; | |
642e522c RGS |
45 | } |
46 | ||
1a6a8453 | 47 | sub getExtraParams |
642e522c | 48 | { |
a02d0f6f | 49 | use IO::Compress::Base::Common qw(:Parse); |
1a6a8453 | 50 | return ( 'ParseExtra' => [1, 1, Parse_boolean, 0] ) ; |
642e522c RGS |
51 | } |
52 | ||
1a6a8453 | 53 | sub ckParams |
642e522c | 54 | { |
1a6a8453 PM |
55 | my $self = shift ; |
56 | my $got = shift ; | |
642e522c | 57 | |
1a6a8453 PM |
58 | # gunzip always needs crc32 |
59 | $got->value('CRC32' => 1); | |
642e522c | 60 | |
1a6a8453 | 61 | return 1; |
642e522c RGS |
62 | } |
63 | ||
1a6a8453 | 64 | sub ckMagic |
642e522c | 65 | { |
1a6a8453 | 66 | my $self = shift; |
642e522c | 67 | |
1a6a8453 PM |
68 | my $magic ; |
69 | $self->smartReadExact(\$magic, GZIP_ID_SIZE); | |
642e522c | 70 | |
1a6a8453 | 71 | *$self->{HeaderPending} = $magic ; |
642e522c | 72 | |
1a6a8453 PM |
73 | return $self->HeaderError("Minimum header size is " . |
74 | GZIP_MIN_HEADER_SIZE . " bytes") | |
75 | if length $magic != GZIP_ID_SIZE ; | |
642e522c | 76 | |
1a6a8453 PM |
77 | return $self->HeaderError("Bad Magic") |
78 | if ! isGzipMagic($magic) ; | |
642e522c | 79 | |
1a6a8453 | 80 | *$self->{Type} = 'rfc1952'; |
642e522c | 81 | |
1a6a8453 | 82 | return $magic ; |
642e522c RGS |
83 | } |
84 | ||
1a6a8453 | 85 | sub readHeader |
642e522c | 86 | { |
1a6a8453 PM |
87 | my $self = shift; |
88 | my $magic = shift; | |
642e522c | 89 | |
1a6a8453 | 90 | return $self->_readGzipHeader($magic); |
642e522c RGS |
91 | } |
92 | ||
1a6a8453 | 93 | sub chkTrailer |
642e522c | 94 | { |
1a6a8453 PM |
95 | my $self = shift; |
96 | my $trailer = shift; | |
642e522c | 97 | |
1a6a8453 PM |
98 | # Check CRC & ISIZE |
99 | my ($CRC32, $ISIZE) = unpack("V V", $trailer) ; | |
100 | *$self->{Info}{CRC32} = $CRC32; | |
101 | *$self->{Info}{ISIZE} = $ISIZE; | |
102 | ||
103 | if (*$self->{Strict}) { | |
104 | return $self->TrailerError("CRC mismatch") | |
105 | if $CRC32 != *$self->{Uncomp}->crc32() ; | |
106 | ||
107 | my $exp_isize = *$self->{Uncomp}->uncompressedBytes(); | |
108 | return $self->TrailerError("ISIZE mismatch. Got $ISIZE" | |
109 | . ", expected $exp_isize") | |
110 | if $ISIZE != $exp_isize ; | |
642e522c RGS |
111 | } |
112 | ||
a02d0f6f | 113 | return STATUS_OK; |
1a6a8453 | 114 | } |
642e522c | 115 | |
1a6a8453 PM |
116 | sub isGzipMagic |
117 | { | |
118 | my $buffer = shift ; | |
119 | return 0 if length $buffer < GZIP_ID_SIZE ; | |
120 | my ($id1, $id2) = unpack("C C", $buffer) ; | |
121 | return $id1 == GZIP_ID1 && $id2 == GZIP_ID2 ; | |
642e522c RGS |
122 | } |
123 | ||
1a6a8453 | 124 | sub _readFullGzipHeader($) |
642e522c | 125 | { |
1a6a8453 PM |
126 | my ($self) = @_ ; |
127 | my $magic = '' ; | |
642e522c | 128 | |
1a6a8453 | 129 | $self->smartReadExact(\$magic, GZIP_ID_SIZE); |
642e522c | 130 | |
1a6a8453 | 131 | *$self->{HeaderPending} = $magic ; |
642e522c | 132 | |
1a6a8453 PM |
133 | return $self->HeaderError("Minimum header size is " . |
134 | GZIP_MIN_HEADER_SIZE . " bytes") | |
135 | if length $magic != GZIP_ID_SIZE ; | |
642e522c | 136 | |
642e522c | 137 | |
1a6a8453 PM |
138 | return $self->HeaderError("Bad Magic") |
139 | if ! isGzipMagic($magic) ; | |
642e522c | 140 | |
1a6a8453 PM |
141 | my $status = $self->_readGzipHeader($magic); |
142 | delete *$self->{Transparent} if ! defined $status ; | |
143 | return $status ; | |
642e522c RGS |
144 | } |
145 | ||
1a6a8453 | 146 | sub _readGzipHeader($) |
642e522c | 147 | { |
1a6a8453 PM |
148 | my ($self, $magic) = @_ ; |
149 | my ($HeaderCRC) ; | |
150 | my ($buffer) = '' ; | |
642e522c | 151 | |
1a6a8453 PM |
152 | $self->smartReadExact(\$buffer, GZIP_MIN_HEADER_SIZE - GZIP_ID_SIZE) |
153 | or return $self->HeaderError("Minimum header size is " . | |
154 | GZIP_MIN_HEADER_SIZE . " bytes") ; | |
642e522c | 155 | |
1a6a8453 PM |
156 | my $keep = $magic . $buffer ; |
157 | *$self->{HeaderPending} = $keep ; | |
642e522c | 158 | |
1a6a8453 PM |
159 | # now split out the various parts |
160 | my ($cm, $flag, $mtime, $xfl, $os) = unpack("C C V C C", $buffer) ; | |
642e522c | 161 | |
1a6a8453 PM |
162 | $cm == GZIP_CM_DEFLATED |
163 | or return $self->HeaderError("Not Deflate (CM is $cm)") ; | |
642e522c | 164 | |
1a6a8453 PM |
165 | # check for use of reserved bits |
166 | return $self->HeaderError("Use of Reserved Bits in FLG field.") | |
167 | if $flag & GZIP_FLG_RESERVED ; | |
642e522c | 168 | |
1a6a8453 PM |
169 | my $EXTRA ; |
170 | my @EXTRA = () ; | |
171 | if ($flag & GZIP_FLG_FEXTRA) { | |
172 | $EXTRA = "" ; | |
173 | $self->smartReadExact(\$buffer, GZIP_FEXTRA_HEADER_SIZE) | |
174 | or return $self->TruncatedHeader("FEXTRA Length") ; | |
642e522c | 175 | |
1a6a8453 PM |
176 | my ($XLEN) = unpack("v", $buffer) ; |
177 | $self->smartReadExact(\$EXTRA, $XLEN) | |
178 | or return $self->TruncatedHeader("FEXTRA Body"); | |
179 | $keep .= $buffer . $EXTRA ; | |
642e522c | 180 | |
1a6a8453 PM |
181 | if ($XLEN && *$self->{'ParseExtra'}) { |
182 | my $offset = 0 ; | |
183 | while ($offset < $XLEN) { | |
642e522c | 184 | |
1a6a8453 PM |
185 | return $self->TruncatedHeader("FEXTRA Body") |
186 | if $offset + GZIP_FEXTRA_SUBFIELD_HEADER_SIZE > $XLEN ; | |
642e522c | 187 | |
1a6a8453 PM |
188 | my $id = substr($EXTRA, $offset, GZIP_FEXTRA_SUBFIELD_ID_SIZE); |
189 | $offset += GZIP_FEXTRA_SUBFIELD_ID_SIZE ; | |
642e522c | 190 | |
1a6a8453 PM |
191 | return $self->HeaderError("SubField ID 2nd byte is 0x00") |
192 | if *$self->{Strict} && substr($id, 1, 1) eq "\x00" ; | |
642e522c | 193 | |
1a6a8453 PM |
194 | my ($subLen) = unpack("v", substr($EXTRA, $offset, |
195 | GZIP_FEXTRA_SUBFIELD_LEN_SIZE)) ; | |
196 | $offset += GZIP_FEXTRA_SUBFIELD_LEN_SIZE ; | |
642e522c | 197 | |
1a6a8453 PM |
198 | return $self->TruncatedHeader("FEXTRA Body") |
199 | if $offset + $subLen > $XLEN ; | |
642e522c | 200 | |
1a6a8453 PM |
201 | push @EXTRA, [$id => substr($EXTRA, $offset, $subLen)]; |
202 | $offset += $subLen ; | |
203 | } | |
204 | } | |
205 | } | |
642e522c | 206 | |
1a6a8453 PM |
207 | my $origname ; |
208 | if ($flag & GZIP_FLG_FNAME) { | |
209 | $origname = "" ; | |
210 | while (1) { | |
211 | $self->smartReadExact(\$buffer, 1) | |
212 | or return $self->TruncatedHeader("FNAME"); | |
213 | last if $buffer eq GZIP_NULL_BYTE ; | |
214 | $origname .= $buffer | |
215 | } | |
216 | $keep .= $origname . GZIP_NULL_BYTE ; | |
642e522c | 217 | |
1a6a8453 PM |
218 | return $self->HeaderError("Non ISO 8859-1 Character found in Name") |
219 | if *$self->{Strict} && $origname =~ /$GZIP_FNAME_INVALID_CHAR_RE/o ; | |
220 | } | |
642e522c | 221 | |
1a6a8453 PM |
222 | my $comment ; |
223 | if ($flag & GZIP_FLG_FCOMMENT) { | |
224 | $comment = ""; | |
225 | while (1) { | |
226 | $self->smartReadExact(\$buffer, 1) | |
227 | or return $self->TruncatedHeader("FCOMMENT"); | |
228 | last if $buffer eq GZIP_NULL_BYTE ; | |
229 | $comment .= $buffer | |
230 | } | |
231 | $keep .= $comment . GZIP_NULL_BYTE ; | |
642e522c | 232 | |
1a6a8453 PM |
233 | return $self->HeaderError("Non ISO 8859-1 Character found in Comment") |
234 | if *$self->{Strict} && $comment =~ /$GZIP_FCOMMENT_INVALID_CHAR_RE/o ; | |
235 | } | |
642e522c | 236 | |
1a6a8453 PM |
237 | if ($flag & GZIP_FLG_FHCRC) { |
238 | $self->smartReadExact(\$buffer, GZIP_FHCRC_SIZE) | |
239 | or return $self->TruncatedHeader("FHCRC"); | |
642e522c | 240 | |
1a6a8453 PM |
241 | $HeaderCRC = unpack("v", $buffer) ; |
242 | my $crc16 = crc32($keep) & 0xFF ; | |
642e522c | 243 | |
1a6a8453 PM |
244 | return $self->HeaderError("CRC16 mismatch.") |
245 | if *$self->{Strict} && $crc16 != $HeaderCRC; | |
642e522c | 246 | |
1a6a8453 PM |
247 | $keep .= $buffer ; |
248 | } | |
642e522c | 249 | |
1a6a8453 PM |
250 | # Assume compression method is deflated for xfl tests |
251 | #if ($xfl) { | |
252 | #} | |
642e522c | 253 | |
1a6a8453 | 254 | *$self->{Type} = 'rfc1952'; |
642e522c | 255 | |
1a6a8453 PM |
256 | return { |
257 | 'Type' => 'rfc1952', | |
258 | 'FingerprintLength' => 2, | |
259 | 'HeaderLength' => length $keep, | |
260 | 'TrailerLength' => GZIP_TRAILER_SIZE, | |
261 | 'Header' => $keep, | |
262 | 'isMinimalHeader' => $keep eq GZIP_MINIMUM_HEADER ? 1 : 0, | |
642e522c | 263 | |
1a6a8453 PM |
264 | 'MethodID' => $cm, |
265 | 'MethodName' => $cm == GZIP_CM_DEFLATED ? "Deflated" : "Unknown" , | |
266 | 'TextFlag' => $flag & GZIP_FLG_FTEXT ? 1 : 0, | |
267 | 'HeaderCRCFlag' => $flag & GZIP_FLG_FHCRC ? 1 : 0, | |
268 | 'NameFlag' => $flag & GZIP_FLG_FNAME ? 1 : 0, | |
269 | 'CommentFlag' => $flag & GZIP_FLG_FCOMMENT ? 1 : 0, | |
270 | 'ExtraFlag' => $flag & GZIP_FLG_FEXTRA ? 1 : 0, | |
271 | 'Name' => $origname, | |
272 | 'Comment' => $comment, | |
273 | 'Time' => $mtime, | |
274 | 'OsID' => $os, | |
275 | 'OsName' => defined $GZIP_OS_Names{$os} | |
276 | ? $GZIP_OS_Names{$os} : "Unknown", | |
277 | 'HeaderCRC' => $HeaderCRC, | |
278 | 'Flags' => $flag, | |
279 | 'ExtraFlags' => $xfl, | |
280 | 'ExtraFieldRaw' => $EXTRA, | |
281 | 'ExtraField' => [ @EXTRA ], | |
642e522c | 282 | |
642e522c | 283 | |
1a6a8453 PM |
284 | #'CompSize'=> $compsize, |
285 | #'CRC32'=> $CRC32, | |
286 | #'OrigSize'=> $ISIZE, | |
287 | } | |
642e522c RGS |
288 | } |
289 | ||
290 | ||
1a6a8453 | 291 | 1; |
642e522c | 292 | |
642e522c RGS |
293 | __END__ |
294 | ||
295 | ||
296 | =head1 NAME | |
297 | ||
a02d0f6f | 298 | |
642e522c RGS |
299 | IO::Uncompress::Gunzip - Perl interface to read RFC 1952 files/buffers |
300 | ||
a02d0f6f | 301 | |
642e522c RGS |
302 | =head1 SYNOPSIS |
303 | ||
304 | use IO::Uncompress::Gunzip qw(gunzip $GunzipError) ; | |
305 | ||
306 | my $status = gunzip $input => $output [,OPTS] | |
307 | or die "gunzip failed: $GunzipError\n"; | |
308 | ||
309 | my $z = new IO::Uncompress::Gunzip $input [OPTS] | |
310 | or die "gunzip failed: $GunzipError\n"; | |
311 | ||
312 | $status = $z->read($buffer) | |
313 | $status = $z->read($buffer, $length) | |
314 | $status = $z->read($buffer, $length, $offset) | |
315 | $line = $z->getline() | |
316 | $char = $z->getc() | |
317 | $char = $z->ungetc() | |
a02d0f6f RGS |
318 | $char = $z->opened() |
319 | ||
642e522c | 320 | $status = $z->inflateSync() |
a02d0f6f | 321 | |
642e522c RGS |
322 | $z->trailingData() |
323 | $data = $z->getHeaderInfo() | |
324 | $z->tell() | |
325 | $z->seek($position, $whence) | |
326 | $z->binmode() | |
327 | $z->fileno() | |
328 | $z->eof() | |
329 | $z->close() | |
330 | ||
331 | $GunzipError ; | |
332 | ||
333 | # IO::File mode | |
334 | ||
335 | <$z> | |
336 | read($z, $buffer); | |
337 | read($z, $buffer, $length); | |
338 | read($z, $buffer, $length, $offset); | |
339 | tell($z) | |
340 | seek($z, $position, $whence) | |
341 | binmode($z) | |
342 | fileno($z) | |
343 | eof($z) | |
344 | close($z) | |
345 | ||
346 | ||
347 | =head1 DESCRIPTION | |
348 | ||
349 | ||
350 | ||
351 | B<WARNING -- This is a Beta release>. | |
352 | ||
353 | =over 5 | |
354 | ||
355 | =item * DO NOT use in production code. | |
356 | ||
357 | =item * The documentation is incomplete in places. | |
358 | ||
359 | =item * Parts of the interface defined here are tentative. | |
360 | ||
361 | =item * Please report any problems you find. | |
362 | ||
363 | =back | |
364 | ||
365 | ||
366 | ||
367 | ||
368 | ||
1a6a8453 | 369 | This module provides a Perl interface that allows the reading of |
642e522c RGS |
370 | files/buffers that conform to RFC 1952. |
371 | ||
1a6a8453 | 372 | For writing RFC 1952 files/buffers, see the companion module IO::Compress::Gzip. |
642e522c RGS |
373 | |
374 | ||
375 | ||
376 | =head1 Functional Interface | |
377 | ||
1a6a8453 PM |
378 | A top-level function, C<gunzip>, is provided to carry out |
379 | "one-shot" uncompression between buffers and/or files. For finer | |
380 | control over the uncompression process, see the L</"OO Interface"> | |
381 | section. | |
642e522c RGS |
382 | |
383 | use IO::Uncompress::Gunzip qw(gunzip $GunzipError) ; | |
384 | ||
385 | gunzip $input => $output [,OPTS] | |
386 | or die "gunzip failed: $GunzipError\n"; | |
387 | ||
1a6a8453 | 388 | |
642e522c RGS |
389 | |
390 | The functional interface needs Perl5.005 or better. | |
391 | ||
392 | ||
393 | =head2 gunzip $input => $output [, OPTS] | |
394 | ||
1a6a8453 PM |
395 | |
396 | C<gunzip> expects at least two parameters, C<$input> and C<$output>. | |
642e522c RGS |
397 | |
398 | =head3 The C<$input> parameter | |
399 | ||
400 | The parameter, C<$input>, is used to define the source of | |
401 | the compressed data. | |
402 | ||
403 | It can take one of the following forms: | |
404 | ||
405 | =over 5 | |
406 | ||
407 | =item A filename | |
408 | ||
409 | If the C<$input> parameter is a simple scalar, it is assumed to be a | |
410 | filename. This file will be opened for reading and the input data | |
411 | will be read from it. | |
412 | ||
413 | =item A filehandle | |
414 | ||
415 | If the C<$input> parameter is a filehandle, the input data will be | |
416 | read from it. | |
417 | The string '-' can be used as an alias for standard input. | |
418 | ||
419 | =item A scalar reference | |
420 | ||
421 | If C<$input> is a scalar reference, the input data will be read | |
422 | from C<$$input>. | |
423 | ||
424 | =item An array reference | |
425 | ||
1a6a8453 PM |
426 | If C<$input> is an array reference, each element in the array must be a |
427 | filename. | |
428 | ||
429 | The input data will be read from each file in turn. | |
430 | ||
642e522c | 431 | The complete array will be walked to ensure that it only |
1a6a8453 PM |
432 | contains valid filenames before any data is uncompressed. |
433 | ||
434 | ||
642e522c RGS |
435 | |
436 | =item An Input FileGlob string | |
437 | ||
438 | If C<$input> is a string that is delimited by the characters "<" and ">" | |
439 | C<gunzip> will assume that it is an I<input fileglob string>. The | |
440 | input is the list of files that match the fileglob. | |
441 | ||
442 | If the fileglob does not match any files ... | |
443 | ||
444 | See L<File::GlobMapper|File::GlobMapper> for more details. | |
445 | ||
446 | ||
447 | =back | |
448 | ||
449 | If the C<$input> parameter is any other type, C<undef> will be returned. | |
450 | ||
451 | ||
452 | ||
453 | =head3 The C<$output> parameter | |
454 | ||
455 | The parameter C<$output> is used to control the destination of the | |
456 | uncompressed data. This parameter can take one of these forms. | |
457 | ||
458 | =over 5 | |
459 | ||
460 | =item A filename | |
461 | ||
1a6a8453 PM |
462 | If the C<$output> parameter is a simple scalar, it is assumed to be a |
463 | filename. This file will be opened for writing and the uncompressed | |
464 | data will be written to it. | |
642e522c RGS |
465 | |
466 | =item A filehandle | |
467 | ||
1a6a8453 PM |
468 | If the C<$output> parameter is a filehandle, the uncompressed data |
469 | will be written to it. | |
642e522c RGS |
470 | The string '-' can be used as an alias for standard output. |
471 | ||
472 | ||
473 | =item A scalar reference | |
474 | ||
1a6a8453 PM |
475 | If C<$output> is a scalar reference, the uncompressed data will be |
476 | stored in C<$$output>. | |
642e522c RGS |
477 | |
478 | ||
642e522c RGS |
479 | |
480 | =item An Array Reference | |
481 | ||
1a6a8453 PM |
482 | If C<$output> is an array reference, the uncompressed data will be |
483 | pushed onto the array. | |
642e522c RGS |
484 | |
485 | =item An Output FileGlob | |
486 | ||
487 | If C<$output> is a string that is delimited by the characters "<" and ">" | |
488 | C<gunzip> will assume that it is an I<output fileglob string>. The | |
489 | output is the list of files that match the fileglob. | |
490 | ||
491 | When C<$output> is an fileglob string, C<$input> must also be a fileglob | |
492 | string. Anything else is an error. | |
493 | ||
494 | =back | |
495 | ||
496 | If the C<$output> parameter is any other type, C<undef> will be returned. | |
497 | ||
642e522c | 498 | |
642e522c RGS |
499 | |
500 | =head2 Notes | |
501 | ||
502 | When C<$input> maps to multiple files/buffers and C<$output> is a single | |
1a6a8453 PM |
503 | file/buffer the uncompressed input files/buffers will all be stored |
504 | in C<$output> as a single uncompressed stream. | |
642e522c RGS |
505 | |
506 | ||
507 | ||
508 | =head2 Optional Parameters | |
509 | ||
510 | Unless specified below, the optional parameters for C<gunzip>, | |
511 | C<OPTS>, are the same as those used with the OO interface defined in the | |
512 | L</"Constructor Options"> section below. | |
513 | ||
514 | =over 5 | |
515 | ||
516 | =item AutoClose =E<gt> 0|1 | |
517 | ||
1a6a8453 PM |
518 | This option applies to any input or output data streams to |
519 | C<gunzip> that are filehandles. | |
642e522c RGS |
520 | |
521 | If C<AutoClose> is specified, and the value is true, it will result in all | |
522 | input and/or output filehandles being closed once C<gunzip> has | |
523 | completed. | |
524 | ||
525 | This parameter defaults to 0. | |
526 | ||
527 | ||
528 | ||
1a6a8453 PM |
529 | =item BinModeOut =E<gt> 0|1 |
530 | ||
531 | When writing to a file or filehandle, set C<binmode> before writing to the | |
532 | file. | |
533 | ||
534 | Defaults to 0. | |
535 | ||
536 | ||
537 | ||
538 | ||
539 | ||
642e522c RGS |
540 | =item -Append =E<gt> 0|1 |
541 | ||
542 | TODO | |
543 | ||
1a6a8453 PM |
544 | =item -MultiStream =E<gt> 0|1 |
545 | ||
546 | Creates a new stream after each file. | |
547 | ||
548 | Defaults to 1. | |
549 | ||
642e522c RGS |
550 | |
551 | ||
552 | =back | |
553 | ||
554 | ||
555 | ||
556 | ||
557 | =head2 Examples | |
558 | ||
559 | To read the contents of the file C<file1.txt.gz> and write the | |
560 | compressed data to the file C<file1.txt>. | |
561 | ||
562 | use strict ; | |
563 | use warnings ; | |
564 | use IO::Uncompress::Gunzip qw(gunzip $GunzipError) ; | |
565 | ||
566 | my $input = "file1.txt.gz"; | |
567 | my $output = "file1.txt"; | |
568 | gunzip $input => $output | |
569 | or die "gunzip failed: $GunzipError\n"; | |
570 | ||
571 | ||
572 | To read from an existing Perl filehandle, C<$input>, and write the | |
573 | uncompressed data to a buffer, C<$buffer>. | |
574 | ||
575 | use strict ; | |
576 | use warnings ; | |
577 | use IO::Uncompress::Gunzip qw(gunzip $GunzipError) ; | |
578 | use IO::File ; | |
579 | ||
580 | my $input = new IO::File "<file1.txt.gz" | |
581 | or die "Cannot open 'file1.txt.gz': $!\n" ; | |
582 | my $buffer ; | |
583 | gunzip $input => \$buffer | |
584 | or die "gunzip failed: $GunzipError\n"; | |
585 | ||
586 | To uncompress all files in the directory "/my/home" that match "*.txt.gz" and store the compressed data in the same directory | |
587 | ||
588 | use strict ; | |
589 | use warnings ; | |
590 | use IO::Uncompress::Gunzip qw(gunzip $GunzipError) ; | |
591 | ||
592 | gunzip '</my/home/*.txt.gz>' => '</my/home/#1.txt>' | |
593 | or die "gunzip failed: $GunzipError\n"; | |
594 | ||
595 | and if you want to compress each file one at a time, this will do the trick | |
596 | ||
597 | use strict ; | |
598 | use warnings ; | |
599 | use IO::Uncompress::Gunzip qw(gunzip $GunzipError) ; | |
600 | ||
601 | for my $input ( glob "/my/home/*.txt.gz" ) | |
602 | { | |
603 | my $output = $input; | |
604 | $output =~ s/.gz// ; | |
605 | gunzip $input => $output | |
606 | or die "Error compressing '$input': $GunzipError\n"; | |
607 | } | |
608 | ||
609 | =head1 OO Interface | |
610 | ||
611 | =head2 Constructor | |
612 | ||
613 | The format of the constructor for IO::Uncompress::Gunzip is shown below | |
614 | ||
615 | ||
616 | my $z = new IO::Uncompress::Gunzip $input [OPTS] | |
617 | or die "IO::Uncompress::Gunzip failed: $GunzipError\n"; | |
618 | ||
619 | Returns an C<IO::Uncompress::Gunzip> object on success and undef on failure. | |
620 | The variable C<$GunzipError> will contain an error message on failure. | |
621 | ||
1a6a8453 PM |
622 | If you are running Perl 5.005 or better the object, C<$z>, returned from |
623 | IO::Uncompress::Gunzip can be used exactly like an L<IO::File|IO::File> filehandle. | |
624 | This means that all normal input file operations can be carried out with | |
625 | C<$z>. For example, to read a line from a compressed file/buffer you can | |
626 | use either of these forms | |
642e522c RGS |
627 | |
628 | $line = $z->getline(); | |
629 | $line = <$z>; | |
630 | ||
631 | The mandatory parameter C<$input> is used to determine the source of the | |
632 | compressed data. This parameter can take one of three forms. | |
633 | ||
634 | =over 5 | |
635 | ||
636 | =item A filename | |
637 | ||
638 | If the C<$input> parameter is a scalar, it is assumed to be a filename. This | |
639 | file will be opened for reading and the compressed data will be read from it. | |
640 | ||
641 | =item A filehandle | |
642 | ||
643 | If the C<$input> parameter is a filehandle, the compressed data will be | |
644 | read from it. | |
645 | The string '-' can be used as an alias for standard input. | |
646 | ||
647 | ||
648 | =item A scalar reference | |
649 | ||
650 | If C<$input> is a scalar reference, the compressed data will be read from | |
651 | C<$$output>. | |
652 | ||
653 | =back | |
654 | ||
655 | =head2 Constructor Options | |
656 | ||
657 | ||
658 | The option names defined below are case insensitive and can be optionally | |
659 | prefixed by a '-'. So all of the following are valid | |
660 | ||
661 | -AutoClose | |
662 | -autoclose | |
663 | AUTOCLOSE | |
664 | autoclose | |
665 | ||
666 | OPTS is a combination of the following options: | |
667 | ||
668 | =over 5 | |
669 | ||
670 | =item -AutoClose =E<gt> 0|1 | |
671 | ||
672 | This option is only valid when the C<$input> parameter is a filehandle. If | |
673 | specified, and the value is true, it will result in the file being closed once | |
674 | either the C<close> method is called or the IO::Uncompress::Gunzip object is | |
675 | destroyed. | |
676 | ||
677 | This parameter defaults to 0. | |
678 | ||
679 | =item -MultiStream =E<gt> 0|1 | |
680 | ||
681 | ||
682 | ||
683 | Allows multiple concatenated compressed streams to be treated as a single | |
684 | compressed stream. Decompression will stop once either the end of the | |
685 | file/buffer is reached, an error is encountered (premature eof, corrupt | |
686 | compressed data) or the end of a stream is not immediately followed by the | |
687 | start of another stream. | |
688 | ||
689 | This parameter defaults to 0. | |
690 | ||
691 | ||
692 | ||
693 | =item -Prime =E<gt> $string | |
694 | ||
695 | This option will uncompress the contents of C<$string> before processing the | |
696 | input file/buffer. | |
697 | ||
698 | This option can be useful when the compressed data is embedded in another | |
699 | file/data structure and it is not possible to work out where the compressed | |
1a6a8453 PM |
700 | data begins without having to read the first few bytes. If this is the |
701 | case, the uncompression can be I<primed> with these bytes using this | |
702 | option. | |
642e522c RGS |
703 | |
704 | =item -Transparent =E<gt> 0|1 | |
705 | ||
706 | If this option is set and the input file or buffer is not compressed data, | |
707 | the module will allow reading of it anyway. | |
708 | ||
709 | This option defaults to 1. | |
710 | ||
711 | =item -BlockSize =E<gt> $num | |
712 | ||
1a6a8453 PM |
713 | When reading the compressed input data, IO::Uncompress::Gunzip will read it in |
714 | blocks of C<$num> bytes. | |
642e522c RGS |
715 | |
716 | This option defaults to 4096. | |
717 | ||
718 | =item -InputLength =E<gt> $size | |
719 | ||
1a6a8453 PM |
720 | When present this option will limit the number of compressed bytes read |
721 | from the input file/buffer to C<$size>. This option can be used in the | |
722 | situation where there is useful data directly after the compressed data | |
723 | stream and you know beforehand the exact length of the compressed data | |
724 | stream. | |
642e522c | 725 | |
1a6a8453 PM |
726 | This option is mostly used when reading from a filehandle, in which case |
727 | the file pointer will be left pointing to the first byte directly after the | |
642e522c RGS |
728 | compressed data stream. |
729 | ||
730 | ||
731 | ||
732 | This option defaults to off. | |
733 | ||
734 | =item -Append =E<gt> 0|1 | |
735 | ||
736 | This option controls what the C<read> method does with uncompressed data. | |
737 | ||
1a6a8453 PM |
738 | If set to 1, all uncompressed data will be appended to the output parameter |
739 | of the C<read> method. | |
642e522c | 740 | |
1a6a8453 PM |
741 | If set to 0, the contents of the output parameter of the C<read> method |
742 | will be overwritten by the uncompressed data. | |
642e522c RGS |
743 | |
744 | Defaults to 0. | |
745 | ||
746 | =item -Strict =E<gt> 0|1 | |
747 | ||
748 | ||
749 | ||
750 | This option controls whether the extra checks defined below are used when | |
1a6a8453 PM |
751 | carrying out the decompression. When Strict is on, the extra tests are |
752 | carried out, when Strict is off they are not. | |
642e522c RGS |
753 | |
754 | The default for this option is off. | |
755 | ||
756 | ||
757 | ||
758 | ||
759 | ||
760 | ||
761 | ||
762 | ||
763 | ||
764 | =over 5 | |
765 | ||
766 | =item 1 | |
767 | ||
768 | If the FHCRC bit is set in the gzip FLG header byte, the CRC16 bytes in the | |
769 | header must match the crc16 value of the gzip header actually read. | |
770 | ||
771 | =item 2 | |
772 | ||
773 | If the gzip header contains a name field (FNAME) it consists solely of ISO | |
774 | 8859-1 characters. | |
775 | ||
776 | =item 3 | |
777 | ||
1a6a8453 PM |
778 | If the gzip header contains a comment field (FCOMMENT) it consists solely |
779 | of ISO 8859-1 characters plus line-feed. | |
642e522c RGS |
780 | |
781 | =item 4 | |
782 | ||
783 | If the gzip FEXTRA header field is present it must conform to the sub-field | |
a02d0f6f | 784 | structure as defined in RFC 1952. |
642e522c RGS |
785 | |
786 | =item 5 | |
787 | ||
788 | The CRC32 and ISIZE trailer fields must be present. | |
789 | ||
790 | =item 6 | |
791 | ||
792 | The value of the CRC32 field read must match the crc32 value of the | |
793 | uncompressed data actually contained in the gzip file. | |
794 | ||
795 | =item 7 | |
796 | ||
1a6a8453 PM |
797 | The value of the ISIZE fields read must match the length of the |
798 | uncompressed data actually read from the file. | |
642e522c RGS |
799 | |
800 | =back | |
801 | ||
802 | ||
803 | ||
804 | ||
805 | ||
806 | ||
807 | =item -ParseExtra =E<gt> 0|1 | |
808 | ||
809 | If the gzip FEXTRA header field is present and this option is set, it will | |
810 | force the module to check that it conforms to the sub-field structure as | |
a02d0f6f | 811 | defined in RFC 1952. |
642e522c RGS |
812 | |
813 | If the C<Strict> is on it will automatically enable this option. | |
814 | ||
815 | Defaults to 0. | |
816 | ||
817 | ||
818 | ||
a02d0f6f RGS |
819 | |
820 | ||
642e522c RGS |
821 | =back |
822 | ||
823 | =head2 Examples | |
824 | ||
825 | TODO | |
826 | ||
827 | =head1 Methods | |
828 | ||
829 | =head2 read | |
830 | ||
831 | Usage is | |
832 | ||
833 | $status = $z->read($buffer) | |
834 | ||
835 | Reads a block of compressed data (the size the the compressed block is | |
836 | determined by the C<Buffer> option in the constructor), uncompresses it and | |
1a6a8453 PM |
837 | writes any uncompressed data into C<$buffer>. If the C<Append> parameter is |
838 | set in the constructor, the uncompressed data will be appended to the | |
839 | C<$buffer> parameter. Otherwise C<$buffer> will be overwritten. | |
642e522c | 840 | |
1a6a8453 PM |
841 | Returns the number of uncompressed bytes written to C<$buffer>, zero if eof |
842 | or a negative number on error. | |
642e522c RGS |
843 | |
844 | =head2 read | |
845 | ||
846 | Usage is | |
847 | ||
848 | $status = $z->read($buffer, $length) | |
849 | $status = $z->read($buffer, $length, $offset) | |
850 | ||
851 | $status = read($z, $buffer, $length) | |
852 | $status = read($z, $buffer, $length, $offset) | |
853 | ||
854 | Attempt to read C<$length> bytes of uncompressed data into C<$buffer>. | |
855 | ||
1a6a8453 PM |
856 | The main difference between this form of the C<read> method and the |
857 | previous one, is that this one will attempt to return I<exactly> C<$length> | |
858 | bytes. The only circumstances that this function will not is if end-of-file | |
859 | or an IO error is encountered. | |
642e522c | 860 | |
1a6a8453 PM |
861 | Returns the number of uncompressed bytes written to C<$buffer>, zero if eof |
862 | or a negative number on error. | |
642e522c RGS |
863 | |
864 | ||
865 | =head2 getline | |
866 | ||
867 | Usage is | |
868 | ||
869 | $line = $z->getline() | |
870 | $line = <$z> | |
871 | ||
872 | Reads a single line. | |
873 | ||
874 | This method fully supports the use of of the variable C<$/> | |
875 | (or C<$INPUT_RECORD_SEPARATOR> or C<$RS> when C<English> is in use) to | |
876 | determine what constitutes an end of line. Both paragraph mode and file | |
877 | slurp mode are supported. | |
878 | ||
879 | ||
880 | =head2 getc | |
881 | ||
882 | Usage is | |
883 | ||
884 | $char = $z->getc() | |
885 | ||
886 | Read a single character. | |
887 | ||
888 | =head2 ungetc | |
889 | ||
890 | Usage is | |
891 | ||
892 | $char = $z->ungetc($string) | |
893 | ||
894 | ||
a02d0f6f | 895 | |
642e522c RGS |
896 | =head2 inflateSync |
897 | ||
898 | Usage is | |
899 | ||
900 | $status = $z->inflateSync() | |
901 | ||
902 | TODO | |
903 | ||
a02d0f6f | 904 | |
642e522c RGS |
905 | =head2 getHeaderInfo |
906 | ||
907 | Usage is | |
908 | ||
1a6a8453 PM |
909 | $hdr = $z->getHeaderInfo(); |
910 | @hdrs = $z->getHeaderInfo(); | |
642e522c | 911 | |
1a6a8453 PM |
912 | This method returns either a hash reference (in scalar context) or a list |
913 | or hash references (in array context) that contains information about each | |
914 | of the header fields in the compressed data stream(s). | |
642e522c RGS |
915 | |
916 | ||
917 | ||
1a6a8453 | 918 | =over 5 |
642e522c | 919 | |
1a6a8453 | 920 | =item Name |
642e522c | 921 | |
1a6a8453 PM |
922 | The contents of the Name header field, if present. If no name is |
923 | present, the value will be undef. Note this is different from a zero length | |
924 | name, which will return an empty string. | |
642e522c RGS |
925 | |
926 | =item Comment | |
927 | ||
1a6a8453 PM |
928 | The contents of the Comment header field, if present. If no comment is |
929 | present, the value will be undef. Note this is different from a zero length | |
930 | comment, which will return an empty string. | |
642e522c RGS |
931 | |
932 | =back | |
933 | ||
934 | ||
935 | ||
936 | ||
937 | =head2 tell | |
938 | ||
939 | Usage is | |
940 | ||
941 | $z->tell() | |
942 | tell $z | |
943 | ||
944 | Returns the uncompressed file offset. | |
945 | ||
946 | =head2 eof | |
947 | ||
948 | Usage is | |
949 | ||
950 | $z->eof(); | |
951 | eof($z); | |
952 | ||
953 | ||
954 | ||
955 | Returns true if the end of the compressed input stream has been reached. | |
956 | ||
957 | ||
958 | ||
959 | =head2 seek | |
960 | ||
961 | $z->seek($position, $whence); | |
962 | seek($z, $position, $whence); | |
963 | ||
964 | ||
965 | ||
966 | ||
967 | Provides a sub-set of the C<seek> functionality, with the restriction | |
968 | that it is only legal to seek forward in the input file/buffer. | |
969 | It is a fatal error to attempt to seek backward. | |
970 | ||
971 | ||
972 | ||
973 | The C<$whence> parameter takes one the usual values, namely SEEK_SET, | |
974 | SEEK_CUR or SEEK_END. | |
975 | ||
976 | Returns 1 on success, 0 on failure. | |
977 | ||
978 | =head2 binmode | |
979 | ||
980 | Usage is | |
981 | ||
982 | $z->binmode | |
983 | binmode $z ; | |
984 | ||
985 | This is a noop provided for completeness. | |
986 | ||
a02d0f6f RGS |
987 | =head2 opened |
988 | ||
989 | $z->opened() | |
990 | ||
991 | Returns true if the object currently refers to a opened file/buffer. | |
992 | ||
993 | =head2 autoflush | |
994 | ||
995 | my $prev = $z->autoflush() | |
996 | my $prev = $z->autoflush(EXPR) | |
997 | ||
998 | If the C<$z> object is associated with a file or a filehandle, this method | |
999 | returns the current autoflush setting for the underlying filehandle. If | |
1000 | C<EXPR> is present, and is non-zero, it will enable flushing after every | |
1001 | write/print operation. | |
1002 | ||
1003 | If C<$z> is associated with a buffer, this method has no effect and always | |
1004 | returns C<undef>. | |
1005 | ||
1006 | B<Note> that the special variable C<$|> B<cannot> be used to set or | |
1007 | retrieve the autoflush setting. | |
1008 | ||
1009 | =head2 input_line_number | |
1010 | ||
1011 | $z->input_line_number() | |
1012 | $z->input_line_number(EXPR) | |
1013 | ||
1014 | ||
1015 | ||
1016 | Returns the current uncompressed line number. If C<EXPR> is present it has | |
1017 | the effect of setting the line number. Note that setting the line number | |
1018 | does not change the current position within the file/buffer being read. | |
1019 | ||
1020 | The contents of C<$/> are used to to determine what constitutes a line | |
1021 | terminator. | |
1022 | ||
1023 | ||
1024 | ||
642e522c RGS |
1025 | =head2 fileno |
1026 | ||
1027 | $z->fileno() | |
1028 | fileno($z) | |
1029 | ||
a02d0f6f RGS |
1030 | If the C<$z> object is associated with a file or a filehandle, this method |
1031 | will return the underlying file descriptor. | |
642e522c RGS |
1032 | |
1033 | If the C<$z> object is is associated with a buffer, this method will | |
1034 | return undef. | |
1035 | ||
1036 | =head2 close | |
1037 | ||
1038 | $z->close() ; | |
1039 | close $z ; | |
1040 | ||
1041 | ||
1042 | ||
1043 | Closes the output file/buffer. | |
1044 | ||
1045 | ||
1046 | ||
1047 | For most versions of Perl this method will be automatically invoked if | |
1048 | the IO::Uncompress::Gunzip object is destroyed (either explicitly or by the | |
1049 | variable with the reference to the object going out of scope). The | |
1050 | exceptions are Perl versions 5.005 through 5.00504 and 5.8.0. In | |
1051 | these cases, the C<close> method will be called automatically, but | |
1052 | not until global destruction of all live objects when the program is | |
1053 | terminating. | |
1054 | ||
1055 | Therefore, if you want your scripts to be able to run on all versions | |
1056 | of Perl, you should call C<close> explicitly and not rely on automatic | |
1057 | closing. | |
1058 | ||
1059 | Returns true on success, otherwise 0. | |
1060 | ||
1061 | If the C<AutoClose> option has been enabled when the IO::Uncompress::Gunzip | |
1062 | object was created, and the object is associated with a file, the | |
1063 | underlying file will also be closed. | |
1064 | ||
1065 | ||
1066 | ||
1067 | ||
1068 | =head1 Importing | |
1069 | ||
1070 | No symbolic constants are required by this IO::Uncompress::Gunzip at present. | |
1071 | ||
1072 | =over 5 | |
1073 | ||
1074 | =item :all | |
1075 | ||
1076 | Imports C<gunzip> and C<$GunzipError>. | |
1077 | Same as doing this | |
1078 | ||
1079 | use IO::Uncompress::Gunzip qw(gunzip $GunzipError) ; | |
1080 | ||
1081 | =back | |
1082 | ||
1083 | =head1 EXAMPLES | |
1084 | ||
1085 | ||
1086 | ||
1087 | ||
1088 | =head1 SEE ALSO | |
1089 | ||
a02d0f6f | 1090 | L<Compress::Zlib>, L<IO::Compress::Gzip>, L<IO::Compress::Deflate>, L<IO::Uncompress::Inflate>, L<IO::Compress::RawDeflate>, L<IO::Uncompress::RawInflate>, L<IO::Compress::Bzip2>, L<IO::Uncompress::Bunzip2>, L<IO::Compress::Lzop>, L<IO::Uncompress::UnLzop>, L<IO::Uncompress::AnyInflate>, L<IO::Uncompress::AnyUncompress> |
642e522c RGS |
1091 | |
1092 | L<Compress::Zlib::FAQ|Compress::Zlib::FAQ> | |
1093 | ||
a02d0f6f RGS |
1094 | L<File::GlobMapper|File::GlobMapper>, L<Archive::Zip|Archive::Zip>, |
1095 | L<Archive::Tar|Archive::Tar>, | |
642e522c RGS |
1096 | L<IO::Zlib|IO::Zlib> |
1097 | ||
a02d0f6f | 1098 | |
642e522c RGS |
1099 | For RFC 1950, 1951 and 1952 see |
1100 | F<http://www.faqs.org/rfcs/rfc1950.html>, | |
1101 | F<http://www.faqs.org/rfcs/rfc1951.html> and | |
1102 | F<http://www.faqs.org/rfcs/rfc1952.html> | |
1103 | ||
a02d0f6f RGS |
1104 | The I<zlib> compression library was written by Jean-loup Gailly |
1105 | F<gzip@prep.ai.mit.edu> and Mark Adler F<madler@alumni.caltech.edu>. | |
1106 | ||
1107 | The primary site for the I<zlib> compression library is | |
1108 | F<http://www.zlib.org>. | |
1109 | ||
1110 | The primary site for gzip is F<http://www.gzip.org>. | |
1111 | ||
1112 | ||
1113 | ||
1114 | ||
1115 | ||
1116 | ||
642e522c RGS |
1117 | |
1118 | =head1 AUTHOR | |
1119 | ||
1120 | The I<IO::Uncompress::Gunzip> module was written by Paul Marquess, | |
a02d0f6f | 1121 | F<pmqs@cpan.org>. |
642e522c | 1122 | |
642e522c | 1123 | |
642e522c RGS |
1124 | |
1125 | =head1 MODIFICATION HISTORY | |
1126 | ||
1127 | See the Changes file. | |
1128 | ||
1129 | =head1 COPYRIGHT AND LICENSE | |
1130 | ||
1131 | ||
1a6a8453 | 1132 | Copyright (c) 2005-2006 Paul Marquess. All rights reserved. |
a02d0f6f | 1133 | |
642e522c RGS |
1134 | This program is free software; you can redistribute it and/or |
1135 | modify it under the same terms as Perl itself. | |
1136 |