Commit | Line | Data |
25f0751f |
1 | |
2 | package IO::Compress::Gzip ; |
3 | |
4 | require 5.004 ; |
5 | |
6 | use strict ; |
7 | use warnings; |
8 | use bytes; |
9 | |
10 | |
11 | use IO::Compress::RawDeflate; |
12 | |
13 | use Compress::Raw::Zlib ; |
14 | use IO::Compress::Base::Common qw(:Status :Parse createSelfTiedObject); |
15 | use IO::Compress::Gzip::Constants; |
16 | |
17 | BEGIN |
18 | { |
19 | if (defined &utf8::downgrade ) |
20 | { *noUTF8 = \&utf8::downgrade } |
21 | else |
22 | { *noUTF8 = sub {} } |
23 | } |
24 | |
25 | require Exporter ; |
26 | |
27 | our ($VERSION, @ISA, @EXPORT_OK, %EXPORT_TAGS, $GzipError); |
28 | |
29 | $VERSION = '2.000_08'; |
30 | $GzipError = '' ; |
31 | |
32 | @ISA = qw(Exporter IO::Compress::RawDeflate); |
33 | @EXPORT_OK = qw( $GzipError gzip ) ; |
34 | %EXPORT_TAGS = %IO::Compress::RawDeflate::DEFLATE_CONSTANTS ; |
35 | push @{ $EXPORT_TAGS{all} }, @EXPORT_OK ; |
36 | Exporter::export_ok_tags('all'); |
37 | |
38 | sub new |
39 | { |
40 | my $class = shift ; |
41 | |
42 | my $obj = createSelfTiedObject($class, \$GzipError); |
43 | |
44 | $obj->_create(undef, @_); |
45 | } |
46 | |
47 | |
48 | sub gzip |
49 | { |
50 | my $obj = createSelfTiedObject(undef, \$GzipError); |
51 | return $obj->_def(@_); |
52 | } |
53 | |
54 | #sub newHeader |
55 | #{ |
56 | # my $self = shift ; |
57 | # #return GZIP_MINIMUM_HEADER ; |
58 | # return $self->mkHeader(*$self->{Got}); |
59 | #} |
60 | |
61 | sub getExtraParams |
62 | { |
63 | my $self = shift ; |
64 | |
65 | return ( |
66 | # zlib behaviour |
67 | $self->getZlibParams(), |
68 | |
69 | # Gzip header fields |
70 | 'Minimal' => [0, 1, Parse_boolean, 0], |
71 | 'Comment' => [0, 1, Parse_any, undef], |
72 | 'Name' => [0, 1, Parse_any, undef], |
73 | 'Time' => [0, 1, Parse_any, undef], |
74 | 'TextFlag' => [0, 1, Parse_boolean, 0], |
75 | 'HeaderCRC' => [0, 1, Parse_boolean, 0], |
76 | 'OS_Code' => [0, 1, Parse_unsigned, $Compress::Raw::Zlib::gzip_os_code], |
77 | 'ExtraField'=> [0, 1, Parse_string, undef], |
78 | 'ExtraFlags'=> [0, 1, Parse_any, undef], |
79 | |
80 | ); |
81 | } |
82 | |
83 | |
84 | sub ckParams |
85 | { |
86 | my $self = shift ; |
87 | my $got = shift ; |
88 | |
89 | # gzip always needs crc32 |
90 | $got->value('CRC32' => 1); |
91 | |
92 | return 1 |
93 | if $got->value('Merge') ; |
94 | |
95 | my $lax = ! $got->value('Strict') ; |
96 | |
97 | |
98 | { |
99 | if (! $got->parsed('Time') ) { |
100 | # Modification time defaults to now. |
101 | $got->value('Time' => time) ; |
102 | } |
103 | |
104 | # Check that the Name & Comment don't have embedded NULLs |
105 | # Also check that they only contain ISO 8859-1 chars. |
106 | if ($got->parsed('Name') && defined $got->value('Name')) { |
107 | my $name = $got->value('Name'); |
108 | |
109 | return $self->saveErrorString(undef, "Null Character found in Name", |
110 | Z_DATA_ERROR) |
111 | if ! $lax && $name =~ /\x00/ ; |
112 | |
113 | return $self->saveErrorString(undef, "Non ISO 8859-1 Character found in Name", |
114 | Z_DATA_ERROR) |
115 | if ! $lax && $name =~ /$GZIP_FNAME_INVALID_CHAR_RE/o ; |
116 | } |
117 | |
118 | if ($got->parsed('Comment') && defined $got->value('Comment')) { |
119 | my $comment = $got->value('Comment'); |
120 | |
121 | return $self->saveErrorString(undef, "Null Character found in Comment", |
122 | Z_DATA_ERROR) |
123 | if ! $lax && $comment =~ /\x00/ ; |
124 | |
125 | return $self->saveErrorString(undef, "Non ISO 8859-1 Character found in Comment", |
126 | Z_DATA_ERROR) |
127 | if ! $lax && $comment =~ /$GZIP_FCOMMENT_INVALID_CHAR_RE/o; |
128 | } |
129 | |
130 | if ($got->parsed('OS_Code') ) { |
131 | my $value = $got->value('OS_Code'); |
132 | |
133 | return $self->saveErrorString(undef, "OS_Code must be between 0 and 255, got '$value'") |
134 | if $value < 0 || $value > 255 ; |
135 | |
136 | } |
137 | |
138 | # gzip only supports Deflate at present |
139 | $got->value('Method' => Z_DEFLATED) ; |
140 | |
141 | if ( ! $got->parsed('ExtraFlags')) { |
142 | $got->value('ExtraFlags' => 2) |
143 | if $got->value('Level') == Z_BEST_SPEED ; |
144 | $got->value('ExtraFlags' => 4) |
145 | if $got->value('Level') == Z_BEST_COMPRESSION ; |
146 | } |
147 | |
148 | if ($got->parsed('ExtraField')) { |
149 | |
150 | my $bad = $self->parseExtraField($got, $lax) ; |
151 | return $self->saveErrorString(undef, $bad, Z_DATA_ERROR) |
152 | if $bad ; |
153 | |
154 | my $len = length $got->value('ExtraField') ; |
155 | return $self->saveErrorString(undef, ExtraFieldError("Too Large"), |
156 | Z_DATA_ERROR) |
157 | if $len > GZIP_FEXTRA_MAX_SIZE; |
158 | } |
159 | } |
160 | |
161 | return 1; |
162 | } |
163 | |
164 | sub mkTrailer |
165 | { |
166 | my $self = shift ; |
167 | return pack("V V", *$self->{Compress}->crc32(), |
168 | *$self->{UnCompSize_32bit}); |
169 | } |
170 | |
171 | sub getInverseClass |
172 | { |
173 | return ('IO::Uncompress::Gunzip', |
174 | \$IO::Uncompress::Gunzip::GunzipError); |
175 | } |
176 | |
177 | sub getFileInfo |
178 | { |
179 | my $self = shift ; |
180 | my $params = shift; |
181 | my $filename = shift ; |
182 | |
183 | my $defaultTime = (stat($filename))[9] ; |
184 | |
185 | $params->value('Name' => $filename) |
186 | if ! $params->parsed('Name') ; |
187 | |
188 | $params->value('Time' => $defaultTime) |
189 | if ! $params->parsed('Time') ; |
190 | } |
191 | |
192 | |
193 | sub mkHeader |
194 | { |
195 | my $self = shift ; |
196 | my $param = shift ; |
197 | |
198 | # stort-circuit if a minimal header is requested. |
199 | return GZIP_MINIMUM_HEADER if $param->value('Minimal') ; |
200 | |
201 | # METHOD |
202 | my $method = $param->valueOrDefault('Method', GZIP_CM_DEFLATED) ; |
203 | |
204 | # FLAGS |
205 | my $flags = GZIP_FLG_DEFAULT ; |
206 | $flags |= GZIP_FLG_FTEXT if $param->value('TextFlag') ; |
207 | $flags |= GZIP_FLG_FHCRC if $param->value('HeaderCRC') ; |
208 | $flags |= GZIP_FLG_FEXTRA if $param->wantValue('ExtraField') ; |
209 | $flags |= GZIP_FLG_FNAME if $param->wantValue('Name') ; |
210 | $flags |= GZIP_FLG_FCOMMENT if $param->wantValue('Comment') ; |
211 | |
212 | # MTIME |
213 | my $time = $param->valueOrDefault('Time', GZIP_MTIME_DEFAULT) ; |
214 | |
215 | # EXTRA FLAGS |
216 | my $extra_flags = $param->valueOrDefault('ExtraFlags', GZIP_XFL_DEFAULT); |
217 | |
218 | # OS CODE |
219 | my $os_code = $param->valueOrDefault('OS_Code', GZIP_OS_DEFAULT) ; |
220 | |
221 | |
222 | my $out = pack("C4 V C C", |
223 | GZIP_ID1, # ID1 |
224 | GZIP_ID2, # ID2 |
225 | $method, # Compression Method |
226 | $flags, # Flags |
227 | $time, # Modification Time |
228 | $extra_flags, # Extra Flags |
229 | $os_code, # Operating System Code |
230 | ) ; |
231 | |
232 | # EXTRA |
233 | if ($flags & GZIP_FLG_FEXTRA) { |
234 | my $extra = $param->value('ExtraField') ; |
235 | $out .= pack("v", length $extra) . $extra ; |
236 | } |
237 | |
238 | # NAME |
239 | if ($flags & GZIP_FLG_FNAME) { |
240 | my $name .= $param->value('Name') ; |
241 | $name =~ s/\x00.*$//; |
242 | $out .= $name ; |
243 | # Terminate the filename with NULL unless it already is |
244 | $out .= GZIP_NULL_BYTE |
245 | if !length $name or |
246 | substr($name, 1, -1) ne GZIP_NULL_BYTE ; |
247 | } |
248 | |
249 | # COMMENT |
250 | if ($flags & GZIP_FLG_FCOMMENT) { |
251 | my $comment .= $param->value('Comment') ; |
252 | $comment =~ s/\x00.*$//; |
253 | $out .= $comment ; |
254 | # Terminate the comment with NULL unless it already is |
255 | $out .= GZIP_NULL_BYTE |
256 | if ! length $comment or |
257 | substr($comment, 1, -1) ne GZIP_NULL_BYTE; |
258 | } |
259 | |
260 | # HEADER CRC |
261 | $out .= pack("v", crc32($out) & 0x00FF ) if $param->value('HeaderCRC') ; |
262 | |
263 | noUTF8($out); |
264 | |
265 | return $out ; |
266 | } |
267 | |
268 | sub ExtraFieldError |
269 | { |
270 | return "Error with ExtraField Parameter: $_[0]" ; |
271 | } |
272 | |
273 | sub validateExtraFieldPair |
274 | { |
275 | my $pair = shift ; |
276 | my $lax = shift ; |
277 | |
278 | return ExtraFieldError("Not an array ref") |
279 | unless ref $pair && ref $pair eq 'ARRAY'; |
280 | |
281 | return ExtraFieldError("SubField must have two parts") |
282 | unless @$pair == 2 ; |
283 | |
284 | return ExtraFieldError("SubField ID is a reference") |
285 | if ref $pair->[0] ; |
286 | |
287 | return ExtraFieldError("SubField Data is a reference") |
288 | if ref $pair->[1] ; |
289 | |
290 | # ID is exactly two chars |
291 | return ExtraFieldError("SubField ID not two chars long") |
292 | unless length $pair->[0] == GZIP_FEXTRA_SUBFIELD_ID_SIZE ; |
293 | |
294 | # Check that the 2nd byte of the ID isn't 0 |
295 | return ExtraFieldError("SubField ID 2nd byte is 0x00") |
296 | if ! $lax && substr($pair->[0], 1, 1) eq "\x00" ; |
297 | |
298 | return ExtraFieldError("SubField Data too long") |
299 | if length $pair->[1] > GZIP_FEXTRA_SUBFIELD_MAX_SIZE ; |
300 | |
301 | |
302 | return undef ; |
303 | } |
304 | |
305 | sub parseExtra |
306 | { |
307 | my $data = shift ; |
308 | my $lax = shift ; |
309 | |
310 | return undef |
311 | if $lax ; |
312 | |
313 | my $XLEN = length $data ; |
314 | |
315 | return ExtraFieldError("Too Large") |
316 | if $XLEN > GZIP_FEXTRA_MAX_SIZE; |
317 | |
318 | my $offset = 0 ; |
319 | while ($offset < $XLEN) { |
320 | |
321 | return ExtraFieldError("FEXTRA Body") |
322 | if $offset + GZIP_FEXTRA_SUBFIELD_HEADER_SIZE > $XLEN ; |
323 | |
324 | my $id = substr($data, $offset, GZIP_FEXTRA_SUBFIELD_ID_SIZE); |
325 | $offset += GZIP_FEXTRA_SUBFIELD_ID_SIZE; |
326 | |
327 | my $subLen = unpack("v", substr($data, $offset, |
328 | GZIP_FEXTRA_SUBFIELD_LEN_SIZE)); |
329 | $offset += GZIP_FEXTRA_SUBFIELD_LEN_SIZE ; |
330 | |
331 | return ExtraFieldError("FEXTRA Body") |
332 | if $offset + $subLen > $XLEN ; |
333 | |
334 | my $bad = validateExtraFieldPair( [$id, |
335 | substr($data, $offset, $subLen)], $lax ); |
336 | return $bad if $bad ; |
337 | |
338 | $offset += $subLen ; |
339 | } |
340 | |
341 | return undef ; |
342 | } |
343 | |
344 | sub parseExtraField |
345 | { |
346 | my $self = shift ; |
347 | my $got = shift ; |
348 | my $lax = shift ; |
349 | |
350 | # ExtraField can be any of |
351 | # |
352 | # -ExtraField => $data |
353 | # -ExtraField => [$id1, $data1, |
354 | # $id2, $data2] |
355 | # ... |
356 | # ] |
357 | # -ExtraField => [ [$id1 => $data1], |
358 | # [$id2 => $data2], |
359 | # ... |
360 | # ] |
361 | # -ExtraField => { $id1 => $data1, |
362 | # $id2 => $data2, |
363 | # ... |
364 | # } |
365 | |
366 | |
367 | return undef |
368 | unless $got->parsed('ExtraField') ; |
369 | |
370 | return parseExtra($got->value('ExtraField'), $lax) |
371 | unless ref $got->value('ExtraField') ; |
372 | |
373 | my $data = $got->value('ExtraField'); |
374 | my $out = '' ; |
375 | |
376 | if (ref $data eq 'ARRAY') { |
377 | if (ref $data->[0]) { |
378 | |
379 | foreach my $pair (@$data) { |
380 | return ExtraFieldError("Not list of lists") |
381 | unless ref $pair eq 'ARRAY' ; |
382 | |
383 | my $bad = validateExtraFieldPair($pair, $lax) ; |
384 | return $bad if $bad ; |
385 | |
386 | $out .= $pair->[0] . pack("v", length $pair->[1]) . |
387 | $pair->[1] ; |
388 | } |
389 | } |
390 | else { |
391 | return ExtraFieldError("Not even number of elements") |
392 | unless @$data % 2 == 0; |
393 | |
394 | for (my $ix = 0; $ix <= length(@$data) -1 ; $ix += 2) { |
395 | my $bad = validateExtraFieldPair([$data->[$ix], $data->[$ix+1]], $lax) ; |
396 | return $bad if $bad ; |
397 | |
398 | $out .= $data->[$ix] . pack("v", length $data->[$ix+1]) . |
399 | $data->[$ix+1] ; |
400 | } |
401 | } |
402 | } |
403 | elsif (ref $data eq 'HASH') { |
404 | while (my ($id, $info) = each %$data) { |
405 | my $bad = validateExtraFieldPair([$id, $info], $lax); |
406 | return $bad if $bad ; |
407 | |
408 | $out .= $id . pack("v", length $info) . $info ; |
409 | } |
410 | } |
411 | else { |
412 | return ExtraFieldError("Not a scalar, array ref or hash ref") ; |
413 | } |
414 | |
415 | $got->value('ExtraField' => $out); |
416 | |
417 | return undef; |
418 | } |
419 | |
420 | sub mkFinalTrailer |
421 | { |
422 | return ''; |
423 | } |
424 | |
425 | 1; |
426 | |
427 | __END__ |
428 | |
429 | =head1 NAME |
430 | |
431 | |
432 | IO::Compress::Gzip - Perl interface to write RFC 1952 files/buffers |
433 | |
434 | |
435 | =head1 SYNOPSIS |
436 | |
437 | use IO::Compress::Gzip qw(gzip $GzipError) ; |
438 | |
439 | |
440 | my $status = gzip $input => $output [,OPTS] |
441 | or die "gzip failed: $GzipError\n"; |
442 | |
443 | my $z = new IO::Compress::Gzip $output [,OPTS] |
444 | or die "gzip failed: $GzipError\n"; |
445 | |
446 | $z->print($string); |
447 | $z->printf($format, $string); |
448 | $z->write($string); |
449 | $z->syswrite($string [, $length, $offset]); |
450 | $z->flush(); |
451 | $z->tell(); |
452 | $z->eof(); |
453 | $z->seek($position, $whence); |
454 | $z->binmode(); |
455 | $z->fileno(); |
456 | $z->opened(); |
457 | $z->autoflush(); |
458 | $z->input_line_number(); |
459 | $z->newStream( [OPTS] ); |
460 | |
461 | $z->deflateParams(); |
462 | |
463 | $z->close() ; |
464 | |
465 | $GzipError ; |
466 | |
467 | # IO::File mode |
468 | |
469 | print $z $string; |
470 | printf $z $format, $string; |
471 | tell $z |
472 | eof $z |
473 | seek $z, $position, $whence |
474 | binmode $z |
475 | fileno $z |
476 | close $z ; |
477 | |
478 | |
479 | =head1 DESCRIPTION |
480 | |
481 | |
482 | |
483 | B<WARNING -- This is a Beta release>. |
484 | |
485 | =over 5 |
486 | |
487 | =item * DO NOT use in production code. |
488 | |
489 | =item * The documentation is incomplete in places. |
490 | |
491 | =item * Parts of the interface defined here are tentative. |
492 | |
493 | =item * Please report any problems you find. |
494 | |
495 | =back |
496 | |
497 | |
498 | |
499 | |
500 | This module provides a Perl interface that allows writing compressed |
501 | data to files or buffer as defined in RFC 1952. |
502 | |
503 | |
504 | |
505 | All the gzip headers defined in RFC 1952 can be created using |
506 | this module. |
507 | |
508 | |
509 | |
510 | |
511 | |
512 | |
513 | |
514 | For reading RFC 1952 files/buffers, see the companion module |
515 | L<IO::Uncompress::Gunzip|IO::Uncompress::Gunzip>. |
516 | |
517 | |
518 | =head1 Functional Interface |
519 | |
520 | A top-level function, C<gzip>, is provided to carry out |
521 | "one-shot" compression between buffers and/or files. For finer |
522 | control over the compression process, see the L</"OO Interface"> |
523 | section. |
524 | |
525 | use IO::Compress::Gzip qw(gzip $GzipError) ; |
526 | |
527 | gzip $input => $output [,OPTS] |
528 | or die "gzip failed: $GzipError\n"; |
529 | |
530 | |
531 | |
532 | The functional interface needs Perl5.005 or better. |
533 | |
534 | |
535 | =head2 gzip $input => $output [, OPTS] |
536 | |
537 | |
538 | C<gzip> expects at least two parameters, C<$input> and C<$output>. |
539 | |
540 | =head3 The C<$input> parameter |
541 | |
542 | The parameter, C<$input>, is used to define the source of |
543 | the uncompressed data. |
544 | |
545 | It can take one of the following forms: |
546 | |
547 | =over 5 |
548 | |
549 | =item A filename |
550 | |
551 | If the C<$input> parameter is a simple scalar, it is assumed to be a |
552 | filename. This file will be opened for reading and the input data |
553 | will be read from it. |
554 | |
555 | =item A filehandle |
556 | |
557 | If the C<$input> parameter is a filehandle, the input data will be |
558 | read from it. |
559 | The string '-' can be used as an alias for standard input. |
560 | |
561 | =item A scalar reference |
562 | |
563 | If C<$input> is a scalar reference, the input data will be read |
564 | from C<$$input>. |
565 | |
566 | =item An array reference |
567 | |
568 | If C<$input> is an array reference, each element in the array must be a |
569 | filename. |
570 | |
571 | The input data will be read from each file in turn. |
572 | |
573 | The complete array will be walked to ensure that it only |
574 | contains valid filenames before any data is compressed. |
575 | |
576 | |
577 | |
578 | =item An Input FileGlob string |
579 | |
580 | If C<$input> is a string that is delimited by the characters "<" and ">" |
581 | C<gzip> will assume that it is an I<input fileglob string>. The |
582 | input is the list of files that match the fileglob. |
583 | |
584 | If the fileglob does not match any files ... |
585 | |
586 | See L<File::GlobMapper|File::GlobMapper> for more details. |
587 | |
588 | |
589 | =back |
590 | |
591 | If the C<$input> parameter is any other type, C<undef> will be returned. |
592 | |
593 | |
594 | |
595 | In addition, if C<$input> is a simple filename, the default values for |
596 | a number of the gzip header fields created by this function will |
597 | be sourced from that file -- |
598 | |
599 | the NAME gzip header field will be populated with |
600 | the filename itself, and the MTIME header field will be set to the |
601 | modification time of the file. |
602 | The intention here is to mirror part of the behaviour of the gzip |
603 | executable. |
604 | |
605 | If you do not want to use these defaults they can be overridden by |
606 | explicitly setting the C<Name> and C<Time> options or by setting the |
607 | C<Minimal> parameter. |
608 | |
609 | |
610 | |
611 | =head3 The C<$output> parameter |
612 | |
613 | The parameter C<$output> is used to control the destination of the |
614 | compressed data. This parameter can take one of these forms. |
615 | |
616 | =over 5 |
617 | |
618 | =item A filename |
619 | |
620 | If the C<$output> parameter is a simple scalar, it is assumed to be a |
621 | filename. This file will be opened for writing and the compressed |
622 | data will be written to it. |
623 | |
624 | =item A filehandle |
625 | |
626 | If the C<$output> parameter is a filehandle, the compressed data |
627 | will be written to it. |
628 | The string '-' can be used as an alias for standard output. |
629 | |
630 | |
631 | =item A scalar reference |
632 | |
633 | If C<$output> is a scalar reference, the compressed data will be |
634 | stored in C<$$output>. |
635 | |
636 | |
637 | |
638 | =item An Array Reference |
639 | |
640 | If C<$output> is an array reference, the compressed data will be |
641 | pushed onto the array. |
642 | |
643 | =item An Output FileGlob |
644 | |
645 | If C<$output> is a string that is delimited by the characters "<" and ">" |
646 | C<gzip> will assume that it is an I<output fileglob string>. The |
647 | output is the list of files that match the fileglob. |
648 | |
649 | When C<$output> is an fileglob string, C<$input> must also be a fileglob |
650 | string. Anything else is an error. |
651 | |
652 | =back |
653 | |
654 | If the C<$output> parameter is any other type, C<undef> will be returned. |
655 | |
656 | |
657 | |
658 | =head2 Notes |
659 | |
660 | When C<$input> maps to multiple files/buffers and C<$output> is a single |
661 | file/buffer the compressed input files/buffers will all be stored |
662 | in C<$output> as a single compressed stream. |
663 | |
664 | |
665 | |
666 | =head2 Optional Parameters |
667 | |
668 | Unless specified below, the optional parameters for C<gzip>, |
669 | C<OPTS>, are the same as those used with the OO interface defined in the |
670 | L</"Constructor Options"> section below. |
671 | |
672 | =over 5 |
673 | |
674 | =item AutoClose =E<gt> 0|1 |
675 | |
676 | This option applies to any input or output data streams to |
677 | C<gzip> that are filehandles. |
678 | |
679 | If C<AutoClose> is specified, and the value is true, it will result in all |
680 | input and/or output filehandles being closed once C<gzip> has |
681 | completed. |
682 | |
683 | This parameter defaults to 0. |
684 | |
685 | |
686 | |
687 | =item BinModeIn =E<gt> 0|1 |
688 | |
689 | When reading from a file or filehandle, set C<binmode> before reading. |
690 | |
691 | Defaults to 0. |
692 | |
693 | |
694 | |
695 | |
696 | |
697 | =item -Append =E<gt> 0|1 |
698 | |
699 | TODO |
700 | |
701 | |
702 | =back |
703 | |
704 | |
705 | |
706 | =head2 Examples |
707 | |
708 | To read the contents of the file C<file1.txt> and write the compressed |
709 | data to the file C<file1.txt.gz>. |
710 | |
711 | use strict ; |
712 | use warnings ; |
713 | use IO::Compress::Gzip qw(gzip $GzipError) ; |
714 | |
715 | my $input = "file1.txt"; |
716 | gzip $input => "$input.gz" |
717 | or die "gzip failed: $GzipError\n"; |
718 | |
719 | |
720 | To read from an existing Perl filehandle, C<$input>, and write the |
721 | compressed data to a buffer, C<$buffer>. |
722 | |
723 | use strict ; |
724 | use warnings ; |
725 | use IO::Compress::Gzip qw(gzip $GzipError) ; |
726 | use IO::File ; |
727 | |
728 | my $input = new IO::File "<file1.txt" |
729 | or die "Cannot open 'file1.txt': $!\n" ; |
730 | my $buffer ; |
731 | gzip $input => \$buffer |
732 | or die "gzip failed: $GzipError\n"; |
733 | |
734 | To compress all files in the directory "/my/home" that match "*.txt" |
735 | and store the compressed data in the same directory |
736 | |
737 | use strict ; |
738 | use warnings ; |
739 | use IO::Compress::Gzip qw(gzip $GzipError) ; |
740 | |
741 | gzip '</my/home/*.txt>' => '<*.gz>' |
742 | or die "gzip failed: $GzipError\n"; |
743 | |
744 | and if you want to compress each file one at a time, this will do the trick |
745 | |
746 | use strict ; |
747 | use warnings ; |
748 | use IO::Compress::Gzip qw(gzip $GzipError) ; |
749 | |
750 | for my $input ( glob "/my/home/*.txt" ) |
751 | { |
752 | my $output = "$input.gz" ; |
753 | gzip $input => $output |
754 | or die "Error compressing '$input': $GzipError\n"; |
755 | } |
756 | |
757 | |
758 | =head1 OO Interface |
759 | |
760 | =head2 Constructor |
761 | |
762 | The format of the constructor for C<IO::Compress::Gzip> is shown below |
763 | |
764 | my $z = new IO::Compress::Gzip $output [,OPTS] |
765 | or die "IO::Compress::Gzip failed: $GzipError\n"; |
766 | |
767 | It returns an C<IO::Compress::Gzip> object on success and undef on failure. |
768 | The variable C<$GzipError> will contain an error message on failure. |
769 | |
770 | If you are running Perl 5.005 or better the object, C<$z>, returned from |
771 | IO::Compress::Gzip can be used exactly like an L<IO::File|IO::File> filehandle. |
772 | This means that all normal output file operations can be carried out |
773 | with C<$z>. |
774 | For example, to write to a compressed file/buffer you can use either of |
775 | these forms |
776 | |
777 | $z->print("hello world\n"); |
778 | print $z "hello world\n"; |
779 | |
780 | The mandatory parameter C<$output> is used to control the destination |
781 | of the compressed data. This parameter can take one of these forms. |
782 | |
783 | =over 5 |
784 | |
785 | =item A filename |
786 | |
787 | If the C<$output> parameter is a simple scalar, it is assumed to be a |
788 | filename. This file will be opened for writing and the compressed data |
789 | will be written to it. |
790 | |
791 | =item A filehandle |
792 | |
793 | If the C<$output> parameter is a filehandle, the compressed data will be |
794 | written to it. |
795 | The string '-' can be used as an alias for standard output. |
796 | |
797 | |
798 | =item A scalar reference |
799 | |
800 | If C<$output> is a scalar reference, the compressed data will be stored |
801 | in C<$$output>. |
802 | |
803 | =back |
804 | |
805 | If the C<$output> parameter is any other type, C<IO::Compress::Gzip>::new will |
806 | return undef. |
807 | |
808 | =head2 Constructor Options |
809 | |
810 | C<OPTS> is any combination of the following options: |
811 | |
812 | =over 5 |
813 | |
814 | =item AutoClose =E<gt> 0|1 |
815 | |
816 | This option is only valid when the C<$output> parameter is a filehandle. If |
817 | specified, and the value is true, it will result in the C<$output> being |
818 | closed once either the C<close> method is called or the C<IO::Compress::Gzip> |
819 | object is destroyed. |
820 | |
821 | This parameter defaults to 0. |
822 | |
823 | =item Append =E<gt> 0|1 |
824 | |
825 | Opens C<$output> in append mode. |
826 | |
827 | The behaviour of this option is dependent on the type of C<$output>. |
828 | |
829 | =over 5 |
830 | |
831 | =item * A Buffer |
832 | |
833 | If C<$output> is a buffer and C<Append> is enabled, all compressed data |
834 | will be append to the end if C<$output>. Otherwise C<$output> will be |
835 | cleared before any data is written to it. |
836 | |
837 | =item * A Filename |
838 | |
839 | If C<$output> is a filename and C<Append> is enabled, the file will be |
840 | opened in append mode. Otherwise the contents of the file, if any, will be |
841 | truncated before any compressed data is written to it. |
842 | |
843 | =item * A Filehandle |
844 | |
845 | If C<$output> is a filehandle, the file pointer will be positioned to the |
846 | end of the file via a call to C<seek> before any compressed data is written |
847 | to it. Otherwise the file pointer will not be moved. |
848 | |
849 | =back |
850 | |
851 | This parameter defaults to 0. |
852 | |
853 | |
854 | |
855 | |
856 | |
857 | =item -Merge =E<gt> 0|1 |
858 | |
859 | This option is used to compress input data and append it to an existing |
860 | compressed data stream in C<$output>. The end result is a single compressed |
861 | data stream stored in C<$output>. |
862 | |
863 | |
864 | |
865 | It is a fatal error to attempt to use this option when C<$output> is not an |
866 | RFC 1952 data stream. |
867 | |
868 | |
869 | |
870 | There are a number of other limitations with the C<Merge> option: |
871 | |
872 | =over 5 |
873 | |
874 | =item 1 |
875 | |
876 | This module needs to have been built with zlib 1.2.1 or better to work. A |
877 | fatal error will be thrown if C<Merge> is used with an older version of |
878 | zlib. |
879 | |
880 | =item 2 |
881 | |
882 | If C<$output> is a file or a filehandle, it must be seekable. |
883 | |
884 | =back |
885 | |
886 | |
887 | This parameter defaults to 0. |
888 | |
889 | |
890 | |
891 | =item -Level |
892 | |
893 | Defines the compression level used by zlib. The value should either be |
894 | a number between 0 and 9 (0 means no compression and 9 is maximum |
895 | compression), or one of the symbolic constants defined below. |
896 | |
897 | Z_NO_COMPRESSION |
898 | Z_BEST_SPEED |
899 | Z_BEST_COMPRESSION |
900 | Z_DEFAULT_COMPRESSION |
901 | |
902 | The default is Z_DEFAULT_COMPRESSION. |
903 | |
904 | Note, these constants are not imported by C<IO::Compress::Gzip> by default. |
905 | |
906 | use IO::Compress::Gzip qw(:strategy); |
907 | use IO::Compress::Gzip qw(:constants); |
908 | use IO::Compress::Gzip qw(:all); |
909 | |
910 | =item -Strategy |
911 | |
912 | Defines the strategy used to tune the compression. Use one of the symbolic |
913 | constants defined below. |
914 | |
915 | Z_FILTERED |
916 | Z_HUFFMAN_ONLY |
917 | Z_RLE |
918 | Z_FIXED |
919 | Z_DEFAULT_STRATEGY |
920 | |
921 | The default is Z_DEFAULT_STRATEGY. |
922 | |
923 | |
924 | |
925 | |
926 | |
927 | |
928 | =item -Minimal =E<gt> 0|1 |
929 | |
930 | If specified, this option will force the creation of the smallest possible |
931 | compliant gzip header (which is exactly 10 bytes long) as defined in |
932 | RFC 1952. |
933 | |
934 | See the section titled "Compliance" in RFC 1952 for a definition |
935 | of the values used for the fields in the gzip header. |
936 | |
937 | All other parameters that control the content of the gzip header will |
938 | be ignored if this parameter is set to 1. |
939 | |
940 | This parameter defaults to 0. |
941 | |
942 | =item -Comment =E<gt> $comment |
943 | |
944 | Stores the contents of C<$comment> in the COMMENT field in |
945 | the gzip header. |
946 | By default, no comment field is written to the gzip file. |
947 | |
948 | If the C<-Strict> option is enabled, the comment can only consist of ISO |
949 | 8859-1 characters plus line feed. |
950 | |
951 | If the C<-Strict> option is disabled, the comment field can contain any |
952 | character except NULL. If any null characters are present, the field |
953 | will be truncated at the first NULL. |
954 | |
955 | =item -Name =E<gt> $string |
956 | |
957 | Stores the contents of C<$string> in the gzip NAME header field. If |
958 | C<Name> is not specified, no gzip NAME field will be created. |
959 | |
960 | If the C<-Strict> option is enabled, C<$string> can only consist of ISO |
961 | 8859-1 characters. |
962 | |
963 | If C<-Strict> is disabled, then C<$string> can contain any character |
964 | except NULL. If any null characters are present, the field will be |
965 | truncated at the first NULL. |
966 | |
967 | =item -Time =E<gt> $number |
968 | |
969 | Sets the MTIME field in the gzip header to $number. |
970 | |
971 | This field defaults to the time the C<IO::Compress::Gzip> object was created |
972 | if this option is not specified. |
973 | |
974 | =item -TextFlag =E<gt> 0|1 |
975 | |
976 | This parameter controls the setting of the FLG.FTEXT bit in the gzip |
977 | header. It is used to signal that the data stored in the gzip file/buffer |
978 | is probably text. |
979 | |
980 | The default is 0. |
981 | |
982 | =item -HeaderCRC =E<gt> 0|1 |
983 | |
984 | When true this parameter will set the FLG.FHCRC bit to 1 in the gzip header |
985 | and set the CRC16 header field to the CRC of the complete gzip header |
986 | except the CRC16 field itself. |
987 | |
988 | B<Note> that gzip files created with the C<HeaderCRC> flag set to 1 cannot |
989 | be read by most, if not all, of the the standard gunzip utilities, most |
990 | notably gzip version 1.2.4. You should therefore avoid using this option if |
991 | you want to maximize the portability of your gzip files. |
992 | |
993 | This parameter defaults to 0. |
994 | |
995 | =item -OS_Code =E<gt> $value |
996 | |
997 | Stores C<$value> in the gzip OS header field. A number between 0 and 255 is |
998 | valid. |
999 | |
1000 | If not specified, this parameter defaults to the OS code of the Operating |
1001 | System this module was built on. The value 3 is used as a catch-all for all |
1002 | Unix variants and unknown Operating Systems. |
1003 | |
1004 | =item -ExtraField =E<gt> $data |
1005 | |
1006 | This parameter allows additional metadata to be stored in the ExtraField in |
1007 | the gzip header. An RFC 1952 compliant ExtraField consists of zero or more |
1008 | subfields. Each subfield consists of a two byte header followed by the |
1009 | subfield data. |
1010 | |
1011 | The list of subfields can be supplied in any of the following formats |
1012 | |
1013 | -ExtraField => [$id1, $data1, |
1014 | $id2, $data2, |
1015 | ... |
1016 | ] |
1017 | -ExtraField => [ [$id1 => $data1], |
1018 | [$id2 => $data2], |
1019 | ... |
1020 | ] |
1021 | -ExtraField => { $id1 => $data1, |
1022 | $id2 => $data2, |
1023 | ... |
1024 | } |
1025 | |
1026 | Where C<$id1>, C<$id2> are two byte subfield ID's. The second byte of |
1027 | the ID cannot be 0, unless the C<Strict> option has been disabled. |
1028 | |
1029 | If you use the hash syntax, you have no control over the order in which |
1030 | the ExtraSubFields are stored, plus you cannot have SubFields with |
1031 | duplicate ID. |
1032 | |
1033 | Alternatively the list of subfields can by supplied as a scalar, thus |
1034 | |
1035 | -ExtraField => $rawdata |
1036 | |
1037 | If you use the raw format, and the C<Strict> option is enabled, |
1038 | C<IO::Compress::Gzip> will check that C<$rawdata> consists of zero or more |
1039 | conformant sub-fields. When C<Strict> is disabled, C<$rawdata> can |
1040 | consist of any arbitrary byte stream. |
1041 | |
1042 | The maximum size of the Extra Field 65535 bytes. |
1043 | |
1044 | =item -ExtraFlags =E<gt> $value |
1045 | |
1046 | Sets the XFL byte in the gzip header to C<$value>. |
1047 | |
1048 | If this option is not present, the value stored in XFL field will be |
1049 | determined by the setting of the C<Level> option. |
1050 | |
1051 | If C<Level =E<gt> Z_BEST_SPEED> has been specified then XFL is set to 2. |
1052 | If C<Level =E<gt> Z_BEST_COMPRESSION> has been specified then XFL is set to 4. |
1053 | Otherwise XFL is set to 0. |
1054 | |
1055 | |
1056 | |
1057 | =item -Strict =E<gt> 0|1 |
1058 | |
1059 | |
1060 | |
1061 | C<Strict> will optionally police the values supplied with other options |
1062 | to ensure they are compliant with RFC1952. |
1063 | |
1064 | This option is enabled by default. |
1065 | |
1066 | If C<Strict> is enabled the following behaviour will be policed: |
1067 | |
1068 | =over 5 |
1069 | |
1070 | =item * |
1071 | |
1072 | The value supplied with the C<Name> option can only contain ISO 8859-1 |
1073 | characters. |
1074 | |
1075 | =item * |
1076 | |
1077 | The value supplied with the C<Comment> option can only contain ISO 8859-1 |
1078 | characters plus line-feed. |
1079 | |
1080 | =item * |
1081 | |
1082 | The values supplied with the C<-Name> and C<-Comment> options cannot |
1083 | contain multiple embedded nulls. |
1084 | |
1085 | =item * |
1086 | |
1087 | If an C<ExtraField> option is specified and it is a simple scalar, |
1088 | it must conform to the sub-field structure as defined in RFC 1952. |
1089 | |
1090 | =item * |
1091 | |
1092 | If an C<ExtraField> option is specified the second byte of the ID will be |
1093 | checked in each subfield to ensure that it does not contain the reserved |
1094 | value 0x00. |
1095 | |
1096 | =back |
1097 | |
1098 | When C<Strict> is disabled the following behaviour will be policed: |
1099 | |
1100 | =over 5 |
1101 | |
1102 | =item * |
1103 | |
1104 | The value supplied with C<-Name> option can contain |
1105 | any character except NULL. |
1106 | |
1107 | =item * |
1108 | |
1109 | The value supplied with C<-Comment> option can contain any character |
1110 | except NULL. |
1111 | |
1112 | =item * |
1113 | |
1114 | The values supplied with the C<-Name> and C<-Comment> options can contain |
1115 | multiple embedded nulls. The string written to the gzip header will |
1116 | consist of the characters up to, but not including, the first embedded |
1117 | NULL. |
1118 | |
1119 | =item * |
1120 | |
1121 | If an C<ExtraField> option is specified and it is a simple scalar, the |
1122 | structure will not be checked. The only error is if the length is too big. |
1123 | |
1124 | =item * |
1125 | |
1126 | The ID header in an C<ExtraField> sub-field can consist of any two bytes. |
1127 | |
1128 | =back |
1129 | |
1130 | |
1131 | |
1132 | =back |
1133 | |
1134 | =head2 Examples |
1135 | |
1136 | TODO |
1137 | |
1138 | =head1 Methods |
1139 | |
1140 | =head2 print |
1141 | |
1142 | Usage is |
1143 | |
1144 | $z->print($data) |
1145 | print $z $data |
1146 | |
1147 | Compresses and outputs the contents of the C<$data> parameter. This |
1148 | has the same behaviour as the C<print> built-in. |
1149 | |
1150 | Returns true if successful. |
1151 | |
1152 | =head2 printf |
1153 | |
1154 | Usage is |
1155 | |
1156 | $z->printf($format, $data) |
1157 | printf $z $format, $data |
1158 | |
1159 | Compresses and outputs the contents of the C<$data> parameter. |
1160 | |
1161 | Returns true if successful. |
1162 | |
1163 | =head2 syswrite |
1164 | |
1165 | Usage is |
1166 | |
1167 | $z->syswrite $data |
1168 | $z->syswrite $data, $length |
1169 | $z->syswrite $data, $length, $offset |
1170 | |
1171 | Compresses and outputs the contents of the C<$data> parameter. |
1172 | |
1173 | Returns the number of uncompressed bytes written, or C<undef> if |
1174 | unsuccessful. |
1175 | |
1176 | =head2 write |
1177 | |
1178 | Usage is |
1179 | |
1180 | $z->write $data |
1181 | $z->write $data, $length |
1182 | $z->write $data, $length, $offset |
1183 | |
1184 | Compresses and outputs the contents of the C<$data> parameter. |
1185 | |
1186 | Returns the number of uncompressed bytes written, or C<undef> if |
1187 | unsuccessful. |
1188 | |
1189 | =head2 flush |
1190 | |
1191 | Usage is |
1192 | |
1193 | |
1194 | $z->flush; |
1195 | $z->flush($flush_type); |
1196 | |
1197 | |
1198 | Flushes any pending compressed data to the output file/buffer. |
1199 | |
1200 | |
1201 | This method takes an optional parameter, C<$flush_type>, that controls |
1202 | how the flushing will be carried out. By default the C<$flush_type> |
1203 | used is C<Z_FINISH>. Other valid values for C<$flush_type> are |
1204 | C<Z_NO_FLUSH>, C<Z_SYNC_FLUSH>, C<Z_FULL_FLUSH> and C<Z_BLOCK>. It is |
1205 | strongly recommended that you only set the C<flush_type> parameter if |
1206 | you fully understand the implications of what it does - overuse of C<flush> |
1207 | can seriously degrade the level of compression achieved. See the C<zlib> |
1208 | documentation for details. |
1209 | |
1210 | |
1211 | Returns true on success. |
1212 | |
1213 | |
1214 | =head2 tell |
1215 | |
1216 | Usage is |
1217 | |
1218 | $z->tell() |
1219 | tell $z |
1220 | |
1221 | Returns the uncompressed file offset. |
1222 | |
1223 | =head2 eof |
1224 | |
1225 | Usage is |
1226 | |
1227 | $z->eof(); |
1228 | eof($z); |
1229 | |
1230 | |
1231 | |
1232 | Returns true if the C<close> method has been called. |
1233 | |
1234 | |
1235 | |
1236 | =head2 seek |
1237 | |
1238 | $z->seek($position, $whence); |
1239 | seek($z, $position, $whence); |
1240 | |
1241 | |
1242 | |
1243 | |
1244 | Provides a sub-set of the C<seek> functionality, with the restriction |
1245 | that it is only legal to seek forward in the output file/buffer. |
1246 | It is a fatal error to attempt to seek backward. |
1247 | |
1248 | Empty parts of the file/buffer will have NULL (0x00) bytes written to them. |
1249 | |
1250 | |
1251 | |
1252 | The C<$whence> parameter takes one the usual values, namely SEEK_SET, |
1253 | SEEK_CUR or SEEK_END. |
1254 | |
1255 | Returns 1 on success, 0 on failure. |
1256 | |
1257 | =head2 binmode |
1258 | |
1259 | Usage is |
1260 | |
1261 | $z->binmode |
1262 | binmode $z ; |
1263 | |
1264 | This is a noop provided for completeness. |
1265 | |
1266 | =head2 opened |
1267 | |
1268 | $z->opened() |
1269 | |
1270 | Returns true if the object currently refers to a opened file/buffer. |
1271 | |
1272 | =head2 autoflush |
1273 | |
1274 | my $prev = $z->autoflush() |
1275 | my $prev = $z->autoflush(EXPR) |
1276 | |
1277 | If the C<$z> object is associated with a file or a filehandle, this method |
1278 | returns the current autoflush setting for the underlying filehandle. If |
1279 | C<EXPR> is present, and is non-zero, it will enable flushing after every |
1280 | write/print operation. |
1281 | |
1282 | If C<$z> is associated with a buffer, this method has no effect and always |
1283 | returns C<undef>. |
1284 | |
1285 | B<Note> that the special variable C<$|> B<cannot> be used to set or |
1286 | retrieve the autoflush setting. |
1287 | |
1288 | =head2 input_line_number |
1289 | |
1290 | $z->input_line_number() |
1291 | $z->input_line_number(EXPR) |
1292 | |
1293 | |
1294 | This method always returns C<undef> when compressing. |
1295 | |
1296 | |
1297 | |
1298 | =head2 fileno |
1299 | |
1300 | $z->fileno() |
1301 | fileno($z) |
1302 | |
1303 | If the C<$z> object is associated with a file or a filehandle, this method |
1304 | will return the underlying file descriptor. |
1305 | |
1306 | If the C<$z> object is is associated with a buffer, this method will |
1307 | return undef. |
1308 | |
1309 | =head2 close |
1310 | |
1311 | $z->close() ; |
1312 | close $z ; |
1313 | |
1314 | |
1315 | |
1316 | Flushes any pending compressed data and then closes the output file/buffer. |
1317 | |
1318 | |
1319 | |
1320 | For most versions of Perl this method will be automatically invoked if |
1321 | the IO::Compress::Gzip object is destroyed (either explicitly or by the |
1322 | variable with the reference to the object going out of scope). The |
1323 | exceptions are Perl versions 5.005 through 5.00504 and 5.8.0. In |
1324 | these cases, the C<close> method will be called automatically, but |
1325 | not until global destruction of all live objects when the program is |
1326 | terminating. |
1327 | |
1328 | Therefore, if you want your scripts to be able to run on all versions |
1329 | of Perl, you should call C<close> explicitly and not rely on automatic |
1330 | closing. |
1331 | |
1332 | Returns true on success, otherwise 0. |
1333 | |
1334 | If the C<AutoClose> option has been enabled when the IO::Compress::Gzip |
1335 | object was created, and the object is associated with a file, the |
1336 | underlying file will also be closed. |
1337 | |
1338 | |
1339 | |
1340 | |
1341 | =head2 newStream([OPTS]) |
1342 | |
1343 | Usage is |
1344 | |
1345 | $z->newStream( [OPTS] ) |
1346 | |
1347 | Closes the current compressed data stream and starts a new one. |
1348 | |
1349 | OPTS consists of the following sub-set of the the options that are |
1350 | available when creating the C<$z> object, |
1351 | |
1352 | =over 5 |
1353 | |
1354 | |
1355 | |
1356 | =item * Level |
1357 | |
1358 | |
1359 | |
1360 | =back |
1361 | |
1362 | |
1363 | =head2 deflateParams |
1364 | |
1365 | Usage is |
1366 | |
1367 | $z->deflateParams |
1368 | |
1369 | TODO |
1370 | |
1371 | |
1372 | =head1 Importing |
1373 | |
1374 | |
1375 | A number of symbolic constants are required by some methods in |
1376 | C<IO::Compress::Gzip>. None are imported by default. |
1377 | |
1378 | |
1379 | |
1380 | =over 5 |
1381 | |
1382 | =item :all |
1383 | |
1384 | |
1385 | Imports C<gzip>, C<$GzipError> and all symbolic |
1386 | constants that can be used by C<IO::Compress::Gzip>. Same as doing this |
1387 | |
1388 | use IO::Compress::Gzip qw(gzip $GzipError :constants) ; |
1389 | |
1390 | =item :constants |
1391 | |
1392 | Import all symbolic constants. Same as doing this |
1393 | |
1394 | use IO::Compress::Gzip qw(:flush :level :strategy) ; |
1395 | |
1396 | =item :flush |
1397 | |
1398 | These symbolic constants are used by the C<flush> method. |
1399 | |
1400 | Z_NO_FLUSH |
1401 | Z_PARTIAL_FLUSH |
1402 | Z_SYNC_FLUSH |
1403 | Z_FULL_FLUSH |
1404 | Z_FINISH |
1405 | Z_BLOCK |
1406 | |
1407 | =item :level |
1408 | |
1409 | These symbolic constants are used by the C<Level> option in the constructor. |
1410 | |
1411 | Z_NO_COMPRESSION |
1412 | Z_BEST_SPEED |
1413 | Z_BEST_COMPRESSION |
1414 | Z_DEFAULT_COMPRESSION |
1415 | |
1416 | |
1417 | =item :strategy |
1418 | |
1419 | These symbolic constants are used by the C<Strategy> option in the constructor. |
1420 | |
1421 | Z_FILTERED |
1422 | Z_HUFFMAN_ONLY |
1423 | Z_RLE |
1424 | Z_FIXED |
1425 | Z_DEFAULT_STRATEGY |
1426 | |
1427 | |
1428 | =back |
1429 | |
1430 | For |
1431 | |
1432 | =head1 EXAMPLES |
1433 | |
1434 | TODO |
1435 | |
1436 | |
1437 | |
1438 | |
1439 | |
1440 | |
1441 | =head1 SEE ALSO |
1442 | |
1443 | L<Compress::Zlib>, L<IO::Uncompress::Gunzip>, L<IO::Compress::Deflate>, L<IO::Uncompress::Inflate>, L<IO::Compress::RawDeflate>, L<IO::Uncompress::RawInflate>, L<IO::Compress::Bzip2>, L<IO::Uncompress::Bunzip2>, L<IO::Compress::Lzop>, L<IO::Uncompress::UnLzop>, L<IO::Uncompress::AnyInflate>, L<IO::Uncompress::AnyUncompress> |
1444 | |
1445 | L<Compress::Zlib::FAQ|Compress::Zlib::FAQ> |
1446 | |
1447 | L<File::GlobMapper|File::GlobMapper>, L<Archive::Zip|Archive::Zip>, |
1448 | L<Archive::Tar|Archive::Tar>, |
1449 | L<IO::Zlib|IO::Zlib> |
1450 | |
1451 | |
1452 | For RFC 1950, 1951 and 1952 see |
1453 | F<http://www.faqs.org/rfcs/rfc1950.html>, |
1454 | F<http://www.faqs.org/rfcs/rfc1951.html> and |
1455 | F<http://www.faqs.org/rfcs/rfc1952.html> |
1456 | |
1457 | The I<zlib> compression library was written by Jean-loup Gailly |
1458 | F<gzip@prep.ai.mit.edu> and Mark Adler F<madler@alumni.caltech.edu>. |
1459 | |
1460 | The primary site for the I<zlib> compression library is |
1461 | F<http://www.zlib.org>. |
1462 | |
1463 | The primary site for gzip is F<http://www.gzip.org>. |
1464 | |
1465 | |
1466 | |
1467 | |
1468 | |
1469 | |
1470 | |
1471 | =head1 AUTHOR |
1472 | |
1473 | The I<IO::Compress::Gzip> module was written by Paul Marquess, |
1474 | F<pmqs@cpan.org>. |
1475 | |
1476 | |
1477 | |
1478 | =head1 MODIFICATION HISTORY |
1479 | |
1480 | See the Changes file. |
1481 | |
1482 | =head1 COPYRIGHT AND LICENSE |
1483 | |
1484 | |
1485 | Copyright (c) 2005-2006 Paul Marquess. All rights reserved. |
1486 | |
1487 | This program is free software; you can redistribute it and/or |
1488 | modify it under the same terms as Perl itself. |
1489 | |
1490 | |