Commit | Line | Data |
642e522c |
1 | package IO::Compress::RawDeflate ; |
2 | |
3 | # create RFC1951 |
4 | # |
5 | use strict ; |
6 | use warnings; |
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7 | |
8 | |
9 | use IO::Compress::Base; |
10 | use CompressPlugin::Deflate ; |
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11 | |
12 | require Exporter ; |
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13 | use Compress::Zlib::Common qw(:Status createSelfTiedObject); |
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14 | |
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15 | |
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16 | our ($VERSION, @ISA, @EXPORT_OK, %DEFLATE_CONSTANTS, %EXPORT_TAGS, $RawDeflateError); |
17 | |
18 | $VERSION = '2.000_07'; |
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19 | $RawDeflateError = ''; |
20 | |
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21 | @ISA = qw(Exporter IO::Compress::Base); |
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22 | @EXPORT_OK = qw( $RawDeflateError rawdeflate ) ; |
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23 | push @{ $EXPORT_TAGS{all} }, @EXPORT_OK ; |
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24 | |
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25 | %EXPORT_TAGS = ( flush => [qw{ |
26 | Z_NO_FLUSH |
27 | Z_PARTIAL_FLUSH |
28 | Z_SYNC_FLUSH |
29 | Z_FULL_FLUSH |
30 | Z_FINISH |
31 | Z_BLOCK |
32 | }], |
33 | level => [qw{ |
34 | Z_NO_COMPRESSION |
35 | Z_BEST_SPEED |
36 | Z_BEST_COMPRESSION |
37 | Z_DEFAULT_COMPRESSION |
38 | }], |
39 | strategy => [qw{ |
40 | Z_FILTERED |
41 | Z_HUFFMAN_ONLY |
42 | Z_RLE |
43 | Z_FIXED |
44 | Z_DEFAULT_STRATEGY |
45 | }], |
46 | |
47 | ); |
48 | |
49 | { |
50 | my %seen; |
51 | foreach (keys %EXPORT_TAGS ) |
52 | { |
53 | push @{$EXPORT_TAGS{constants}}, |
54 | grep { !$seen{$_}++ } |
55 | @{ $EXPORT_TAGS{$_} } |
56 | } |
57 | $EXPORT_TAGS{all} = $EXPORT_TAGS{constants} ; |
58 | } |
59 | |
60 | %DEFLATE_CONSTANTS = %EXPORT_TAGS; |
61 | |
62 | Exporter::export_ok_tags('all'); |
63 | |
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64 | |
65 | |
66 | sub new |
67 | { |
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68 | my $class = shift ; |
69 | |
70 | my $obj = createSelfTiedObject($class, \$RawDeflateError); |
71 | |
72 | return $obj->_create(undef, @_); |
642e522c |
73 | } |
74 | |
75 | sub rawdeflate |
76 | { |
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77 | my $obj = createSelfTiedObject(undef, \$RawDeflateError); |
78 | return $obj->_def(@_); |
79 | } |
80 | |
81 | sub ckParams |
82 | { |
83 | my $self = shift ; |
84 | my $got = shift; |
85 | |
86 | return 1 ; |
87 | } |
88 | |
89 | sub mkComp |
90 | { |
91 | my $self = shift ; |
92 | my $class = shift ; |
93 | my $got = shift ; |
94 | |
95 | #return CompressPlugin::Deflate::mkCompObject($self, $class, $got) |
96 | my ($obj, $errstr, $errno) = CompressPlugin::Deflate::mkCompObject( |
97 | $got->value('CRC32'), |
98 | $got->value('Adler32'), |
99 | $got->value('Level'), |
100 | $got->value('Strategy') |
101 | ); |
102 | |
103 | return $self->saveErrorString(undef, $errstr, $errno) |
104 | if ! defined $obj; |
105 | |
106 | return $obj; |
107 | } |
108 | |
109 | |
110 | sub mkHeader |
111 | { |
112 | my $self = shift ; |
113 | return ''; |
114 | } |
115 | |
116 | sub mkTrailer |
117 | { |
118 | my $self = shift ; |
119 | return ''; |
120 | } |
121 | |
122 | sub mkFinalTrailer |
123 | { |
124 | return ''; |
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125 | } |
126 | |
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127 | |
128 | #sub newHeader |
129 | #{ |
130 | # my $self = shift ; |
131 | # return ''; |
132 | #} |
133 | |
134 | sub getExtraParams |
135 | { |
136 | my $self = shift ; |
137 | return $self->getZlibParams(); |
138 | } |
139 | |
140 | sub getZlibParams |
141 | { |
142 | my $self = shift ; |
143 | |
144 | use Compress::Zlib::ParseParameters; |
145 | use Compress::Zlib qw(Z_DEFLATED Z_DEFAULT_COMPRESSION Z_DEFAULT_STRATEGY); |
146 | |
147 | |
148 | return ( |
149 | |
150 | # zlib behaviour |
151 | #'Method' => [0, 1, Parse_unsigned, Z_DEFLATED], |
152 | 'Level' => [0, 1, Parse_signed, Z_DEFAULT_COMPRESSION], |
153 | 'Strategy' => [0, 1, Parse_signed, Z_DEFAULT_STRATEGY], |
154 | |
155 | 'CRC32' => [0, 1, Parse_boolean, 0], |
156 | 'ADLER32' => [0, 1, Parse_boolean, 0], |
157 | 'Merge' => [1, 1, Parse_boolean, 0], |
158 | ); |
159 | |
160 | |
161 | } |
162 | |
163 | sub getInverseClass |
164 | { |
165 | return ('IO::Uncompress::RawInflate', |
166 | \$IO::Uncompress::RawInflate::RawInflateError); |
167 | } |
168 | |
169 | sub getFileInfo |
170 | { |
171 | my $self = shift ; |
172 | my $params = shift; |
173 | my $file = shift ; |
174 | |
175 | } |
176 | |
177 | use IO::Seekable qw(SEEK_SET); |
178 | |
179 | sub createMerge |
180 | { |
181 | my $self = shift ; |
182 | my $outValue = shift ; |
183 | my $outType = shift ; |
184 | |
185 | my ($invClass, $error_ref) = $self->getInverseClass(); |
186 | eval "require $invClass" |
187 | or die "aaaahhhh" ; |
188 | |
189 | my $inf = $invClass->new( $outValue, |
190 | Transparent => 0, |
191 | #Strict => 1, |
192 | AutoClose => 0, |
193 | Scan => 1) |
194 | or return $self->saveErrorString(undef, "Cannot create InflateScan object: $$error_ref" ) ; |
195 | |
196 | my $end_offset = 0; |
197 | $inf->scan() |
198 | or return $self->saveErrorString(undef, "Error Scanning: $$error_ref", $inf->errorNo) ; |
199 | $inf->zap($end_offset) |
200 | or return $self->saveErrorString(undef, "Error Zapping: $$error_ref", $inf->errorNo) ; |
201 | |
202 | my $def = *$self->{Compress} = $inf->createDeflate(); |
203 | |
204 | *$self->{Header} = *$inf->{Info}{Header}; |
205 | *$self->{UnCompSize_32bit} = |
206 | *$self->{BytesWritten} = *$inf->{UnCompSize_32bit} ; |
207 | |
208 | |
209 | if ( $outType eq 'buffer') |
210 | { substr( ${ *$self->{Buffer} }, $end_offset) = '' } |
211 | elsif ($outType eq 'handle' || $outType eq 'filename') { |
212 | *$self->{FH} = *$inf->{FH} ; |
213 | delete *$inf->{FH}; |
214 | *$self->{FH}->flush() ; |
215 | *$self->{Handle} = 1 if $outType eq 'handle'; |
216 | |
217 | #seek(*$self->{FH}, $end_offset, SEEK_SET) |
218 | *$self->{FH}->seek($end_offset, SEEK_SET) |
219 | or return $self->saveErrorString(undef, $!, $!) ; |
220 | } |
221 | |
222 | return $def ; |
223 | } |
224 | |
225 | #### zlib specific methods |
226 | |
227 | sub deflateParams |
228 | { |
229 | my $self = shift ; |
230 | |
231 | my $level = shift ; |
232 | my $strategy = shift ; |
233 | |
234 | my $status = *$self->{Compress}->deflateParams(Level => $level, Strategy => $strategy) ; |
235 | return $self->saveErrorString(0, *$self->{Compress}{Error}, *$self->{Compress}{ErrorNo}) |
236 | if $status == STATUS_ERROR; |
237 | |
238 | return 1; |
239 | } |
240 | |
241 | |
242 | |
243 | |
642e522c |
244 | 1; |
245 | |
246 | __END__ |
247 | |
248 | =head1 NAME |
249 | |
250 | IO::Compress::RawDeflate - Perl interface to write RFC 1951 files/buffers |
251 | |
252 | =head1 SYNOPSIS |
253 | |
254 | use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ; |
255 | |
256 | |
257 | my $status = rawdeflate $input => $output [,OPTS] |
258 | or die "rawdeflate failed: $RawDeflateError\n"; |
259 | |
260 | my $z = new IO::Compress::RawDeflate $output [,OPTS] |
261 | or die "rawdeflate failed: $RawDeflateError\n"; |
262 | |
263 | $z->print($string); |
264 | $z->printf($format, $string); |
265 | $z->write($string); |
266 | $z->syswrite($string [, $length, $offset]); |
267 | $z->flush(); |
268 | $z->tell(); |
269 | $z->eof(); |
270 | $z->seek($position, $whence); |
271 | $z->binmode(); |
272 | $z->fileno(); |
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273 | $z->newStream( [OPTS] ); |
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274 | $z->deflateParams(); |
275 | $z->close() ; |
276 | |
277 | $RawDeflateError ; |
278 | |
279 | # IO::File mode |
280 | |
281 | print $z $string; |
282 | printf $z $format, $string; |
283 | syswrite $z, $string [, $length, $offset]; |
284 | flush $z, ; |
285 | tell $z |
286 | eof $z |
287 | seek $z, $position, $whence |
288 | binmode $z |
289 | fileno $z |
290 | close $z ; |
291 | |
292 | |
293 | =head1 DESCRIPTION |
294 | |
295 | |
296 | |
297 | B<WARNING -- This is a Beta release>. |
298 | |
299 | =over 5 |
300 | |
301 | =item * DO NOT use in production code. |
302 | |
303 | =item * The documentation is incomplete in places. |
304 | |
305 | =item * Parts of the interface defined here are tentative. |
306 | |
307 | =item * Please report any problems you find. |
308 | |
309 | =back |
310 | |
311 | |
312 | |
313 | This module provides a Perl interface that allows writing compressed |
314 | data to files or buffer as defined in RFC 1951. |
315 | |
316 | |
317 | |
318 | |
319 | Note that RFC1951 data is not a good choice of compression format |
320 | to use in isolation, especially if you want to auto-detect it. |
321 | |
322 | |
323 | For reading RFC 1951 files/buffers, see the companion module |
324 | L<IO::Uncompress::RawInflate|IO::Uncompress::RawInflate>. |
325 | |
326 | |
327 | =head1 Functional Interface |
328 | |
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329 | A top-level function, C<rawdeflate>, is provided to carry out |
330 | "one-shot" compression between buffers and/or files. For finer |
331 | control over the compression process, see the L</"OO Interface"> |
332 | section. |
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333 | |
334 | use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ; |
335 | |
336 | rawdeflate $input => $output [,OPTS] |
337 | or die "rawdeflate failed: $RawDeflateError\n"; |
338 | |
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339 | |
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340 | |
341 | The functional interface needs Perl5.005 or better. |
342 | |
343 | |
344 | =head2 rawdeflate $input => $output [, OPTS] |
345 | |
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346 | |
347 | C<rawdeflate> expects at least two parameters, C<$input> and C<$output>. |
642e522c |
348 | |
349 | =head3 The C<$input> parameter |
350 | |
351 | The parameter, C<$input>, is used to define the source of |
352 | the uncompressed data. |
353 | |
354 | It can take one of the following forms: |
355 | |
356 | =over 5 |
357 | |
358 | =item A filename |
359 | |
360 | If the C<$input> parameter is a simple scalar, it is assumed to be a |
361 | filename. This file will be opened for reading and the input data |
362 | will be read from it. |
363 | |
364 | =item A filehandle |
365 | |
366 | If the C<$input> parameter is a filehandle, the input data will be |
367 | read from it. |
368 | The string '-' can be used as an alias for standard input. |
369 | |
370 | =item A scalar reference |
371 | |
372 | If C<$input> is a scalar reference, the input data will be read |
373 | from C<$$input>. |
374 | |
375 | =item An array reference |
376 | |
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377 | If C<$input> is an array reference, each element in the array must be a |
378 | filename. |
379 | |
380 | The input data will be read from each file in turn. |
381 | |
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382 | The complete array will be walked to ensure that it only |
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383 | contains valid filenames before any data is compressed. |
384 | |
385 | |
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386 | |
387 | =item An Input FileGlob string |
388 | |
389 | If C<$input> is a string that is delimited by the characters "<" and ">" |
390 | C<rawdeflate> will assume that it is an I<input fileglob string>. The |
391 | input is the list of files that match the fileglob. |
392 | |
393 | If the fileglob does not match any files ... |
394 | |
395 | See L<File::GlobMapper|File::GlobMapper> for more details. |
396 | |
397 | |
398 | =back |
399 | |
400 | If the C<$input> parameter is any other type, C<undef> will be returned. |
401 | |
402 | |
403 | |
404 | =head3 The C<$output> parameter |
405 | |
406 | The parameter C<$output> is used to control the destination of the |
407 | compressed data. This parameter can take one of these forms. |
408 | |
409 | =over 5 |
410 | |
411 | =item A filename |
412 | |
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413 | If the C<$output> parameter is a simple scalar, it is assumed to be a |
414 | filename. This file will be opened for writing and the compressed |
415 | data will be written to it. |
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416 | |
417 | =item A filehandle |
418 | |
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419 | If the C<$output> parameter is a filehandle, the compressed data |
420 | will be written to it. |
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421 | The string '-' can be used as an alias for standard output. |
422 | |
423 | |
424 | =item A scalar reference |
425 | |
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426 | If C<$output> is a scalar reference, the compressed data will be |
427 | stored in C<$$output>. |
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428 | |
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429 | |
430 | |
431 | =item An Array Reference |
432 | |
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433 | If C<$output> is an array reference, the compressed data will be |
434 | pushed onto the array. |
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435 | |
436 | =item An Output FileGlob |
437 | |
438 | If C<$output> is a string that is delimited by the characters "<" and ">" |
439 | C<rawdeflate> will assume that it is an I<output fileglob string>. The |
440 | output is the list of files that match the fileglob. |
441 | |
442 | When C<$output> is an fileglob string, C<$input> must also be a fileglob |
443 | string. Anything else is an error. |
444 | |
445 | =back |
446 | |
447 | If the C<$output> parameter is any other type, C<undef> will be returned. |
448 | |
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449 | |
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450 | |
451 | =head2 Notes |
452 | |
453 | When C<$input> maps to multiple files/buffers and C<$output> is a single |
1a6a8453 |
454 | file/buffer the compressed input files/buffers will all be stored |
455 | in C<$output> as a single compressed stream. |
642e522c |
456 | |
457 | |
458 | |
459 | =head2 Optional Parameters |
460 | |
461 | Unless specified below, the optional parameters for C<rawdeflate>, |
462 | C<OPTS>, are the same as those used with the OO interface defined in the |
463 | L</"Constructor Options"> section below. |
464 | |
465 | =over 5 |
466 | |
467 | =item AutoClose =E<gt> 0|1 |
468 | |
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469 | This option applies to any input or output data streams to |
470 | C<rawdeflate> that are filehandles. |
642e522c |
471 | |
472 | If C<AutoClose> is specified, and the value is true, it will result in all |
473 | input and/or output filehandles being closed once C<rawdeflate> has |
474 | completed. |
475 | |
476 | This parameter defaults to 0. |
477 | |
478 | |
479 | |
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480 | =item BinModeIn =E<gt> 0|1 |
481 | |
482 | When reading from a file or filehandle, set C<binmode> before reading. |
483 | |
484 | Defaults to 0. |
485 | |
486 | |
487 | |
488 | |
489 | |
642e522c |
490 | =item -Append =E<gt> 0|1 |
491 | |
492 | TODO |
493 | |
494 | |
495 | =back |
496 | |
497 | |
498 | |
499 | =head2 Examples |
500 | |
501 | To read the contents of the file C<file1.txt> and write the compressed |
502 | data to the file C<file1.txt.1951>. |
503 | |
504 | use strict ; |
505 | use warnings ; |
506 | use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ; |
507 | |
508 | my $input = "file1.txt"; |
509 | rawdeflate $input => "$input.1951" |
510 | or die "rawdeflate failed: $RawDeflateError\n"; |
511 | |
512 | |
513 | To read from an existing Perl filehandle, C<$input>, and write the |
514 | compressed data to a buffer, C<$buffer>. |
515 | |
516 | use strict ; |
517 | use warnings ; |
518 | use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ; |
519 | use IO::File ; |
520 | |
521 | my $input = new IO::File "<file1.txt" |
522 | or die "Cannot open 'file1.txt': $!\n" ; |
523 | my $buffer ; |
524 | rawdeflate $input => \$buffer |
525 | or die "rawdeflate failed: $RawDeflateError\n"; |
526 | |
527 | To compress all files in the directory "/my/home" that match "*.txt" |
528 | and store the compressed data in the same directory |
529 | |
530 | use strict ; |
531 | use warnings ; |
532 | use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ; |
533 | |
534 | rawdeflate '</my/home/*.txt>' => '<*.1951>' |
535 | or die "rawdeflate failed: $RawDeflateError\n"; |
536 | |
537 | and if you want to compress each file one at a time, this will do the trick |
538 | |
539 | use strict ; |
540 | use warnings ; |
541 | use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ; |
542 | |
543 | for my $input ( glob "/my/home/*.txt" ) |
544 | { |
545 | my $output = "$input.1951" ; |
546 | rawdeflate $input => $output |
547 | or die "Error compressing '$input': $RawDeflateError\n"; |
548 | } |
549 | |
550 | |
551 | =head1 OO Interface |
552 | |
553 | =head2 Constructor |
554 | |
555 | The format of the constructor for C<IO::Compress::RawDeflate> is shown below |
556 | |
557 | my $z = new IO::Compress::RawDeflate $output [,OPTS] |
558 | or die "IO::Compress::RawDeflate failed: $RawDeflateError\n"; |
559 | |
560 | It returns an C<IO::Compress::RawDeflate> object on success and undef on failure. |
561 | The variable C<$RawDeflateError> will contain an error message on failure. |
562 | |
563 | If you are running Perl 5.005 or better the object, C<$z>, returned from |
564 | IO::Compress::RawDeflate can be used exactly like an L<IO::File|IO::File> filehandle. |
565 | This means that all normal output file operations can be carried out |
566 | with C<$z>. |
567 | For example, to write to a compressed file/buffer you can use either of |
568 | these forms |
569 | |
570 | $z->print("hello world\n"); |
571 | print $z "hello world\n"; |
572 | |
573 | The mandatory parameter C<$output> is used to control the destination |
574 | of the compressed data. This parameter can take one of these forms. |
575 | |
576 | =over 5 |
577 | |
578 | =item A filename |
579 | |
580 | If the C<$output> parameter is a simple scalar, it is assumed to be a |
581 | filename. This file will be opened for writing and the compressed data |
582 | will be written to it. |
583 | |
584 | =item A filehandle |
585 | |
586 | If the C<$output> parameter is a filehandle, the compressed data will be |
587 | written to it. |
588 | The string '-' can be used as an alias for standard output. |
589 | |
590 | |
591 | =item A scalar reference |
592 | |
593 | If C<$output> is a scalar reference, the compressed data will be stored |
594 | in C<$$output>. |
595 | |
596 | =back |
597 | |
598 | If the C<$output> parameter is any other type, C<IO::Compress::RawDeflate>::new will |
599 | return undef. |
600 | |
601 | =head2 Constructor Options |
602 | |
603 | C<OPTS> is any combination of the following options: |
604 | |
605 | =over 5 |
606 | |
607 | =item -AutoClose =E<gt> 0|1 |
608 | |
609 | This option is only valid when the C<$output> parameter is a filehandle. If |
1a6a8453 |
610 | specified, and the value is true, it will result in the C<$output> being |
611 | closed once either the C<close> method is called or the C<IO::Compress::RawDeflate> |
612 | object is destroyed. |
642e522c |
613 | |
614 | This parameter defaults to 0. |
615 | |
616 | =item -Append =E<gt> 0|1 |
617 | |
618 | Opens C<$output> in append mode. |
619 | |
1a6a8453 |
620 | The behaviour of this option is dependent on the type of C<$output>. |
642e522c |
621 | |
622 | =over 5 |
623 | |
624 | =item * A Buffer |
625 | |
1a6a8453 |
626 | If C<$output> is a buffer and C<Append> is enabled, all compressed data |
627 | will be append to the end if C<$output>. Otherwise C<$output> will be |
628 | cleared before any data is written to it. |
642e522c |
629 | |
630 | =item * A Filename |
631 | |
1a6a8453 |
632 | If C<$output> is a filename and C<Append> is enabled, the file will be |
633 | opened in append mode. Otherwise the contents of the file, if any, will be |
634 | truncated before any compressed data is written to it. |
642e522c |
635 | |
636 | =item * A Filehandle |
637 | |
1a6a8453 |
638 | If C<$output> is a filehandle, the file pointer will be positioned to the |
639 | end of the file via a call to C<seek> before any compressed data is written |
640 | to it. Otherwise the file pointer will not be moved. |
642e522c |
641 | |
642 | =back |
643 | |
644 | This parameter defaults to 0. |
645 | |
646 | =item -Merge =E<gt> 0|1 |
647 | |
648 | This option is used to compress input data and append it to an existing |
649 | compressed data stream in C<$output>. The end result is a single compressed |
650 | data stream stored in C<$output>. |
651 | |
652 | |
653 | |
1a6a8453 |
654 | It is a fatal error to attempt to use this option when C<$output> is not an |
655 | RFC 1951 data stream. |
642e522c |
656 | |
657 | |
658 | |
659 | There are a number of other limitations with the C<Merge> option: |
660 | |
661 | =over 5 |
662 | |
663 | =item 1 |
664 | |
1a6a8453 |
665 | This module needs to have been built with zlib 1.2.1 or better to work. A |
666 | fatal error will be thrown if C<Merge> is used with an older version of |
667 | zlib. |
642e522c |
668 | |
669 | =item 2 |
670 | |
671 | If C<$output> is a file or a filehandle, it must be seekable. |
672 | |
673 | =back |
674 | |
675 | |
676 | This parameter defaults to 0. |
677 | |
678 | =item -Level |
679 | |
680 | Defines the compression level used by zlib. The value should either be |
681 | a number between 0 and 9 (0 means no compression and 9 is maximum |
682 | compression), or one of the symbolic constants defined below. |
683 | |
684 | Z_NO_COMPRESSION |
685 | Z_BEST_SPEED |
686 | Z_BEST_COMPRESSION |
687 | Z_DEFAULT_COMPRESSION |
688 | |
689 | The default is Z_DEFAULT_COMPRESSION. |
690 | |
691 | Note, these constants are not imported by C<IO::Compress::RawDeflate> by default. |
692 | |
693 | use IO::Compress::RawDeflate qw(:strategy); |
694 | use IO::Compress::RawDeflate qw(:constants); |
695 | use IO::Compress::RawDeflate qw(:all); |
696 | |
697 | =item -Strategy |
698 | |
699 | Defines the strategy used to tune the compression. Use one of the symbolic |
700 | constants defined below. |
701 | |
702 | Z_FILTERED |
703 | Z_HUFFMAN_ONLY |
704 | Z_RLE |
705 | Z_FIXED |
706 | Z_DEFAULT_STRATEGY |
707 | |
708 | The default is Z_DEFAULT_STRATEGY. |
709 | |
710 | |
711 | |
712 | |
713 | |
714 | =item -Strict =E<gt> 0|1 |
715 | |
716 | |
717 | |
718 | This is a placeholder option. |
719 | |
720 | |
721 | |
722 | =back |
723 | |
724 | =head2 Examples |
725 | |
726 | TODO |
727 | |
728 | =head1 Methods |
729 | |
730 | =head2 print |
731 | |
732 | Usage is |
733 | |
734 | $z->print($data) |
735 | print $z $data |
736 | |
737 | Compresses and outputs the contents of the C<$data> parameter. This |
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738 | has the same behaviour as the C<print> built-in. |
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739 | |
740 | Returns true if successful. |
741 | |
742 | =head2 printf |
743 | |
744 | Usage is |
745 | |
746 | $z->printf($format, $data) |
747 | printf $z $format, $data |
748 | |
749 | Compresses and outputs the contents of the C<$data> parameter. |
750 | |
751 | Returns true if successful. |
752 | |
753 | =head2 syswrite |
754 | |
755 | Usage is |
756 | |
757 | $z->syswrite $data |
758 | $z->syswrite $data, $length |
759 | $z->syswrite $data, $length, $offset |
760 | |
761 | syswrite $z, $data |
762 | syswrite $z, $data, $length |
763 | syswrite $z, $data, $length, $offset |
764 | |
765 | Compresses and outputs the contents of the C<$data> parameter. |
766 | |
767 | Returns the number of uncompressed bytes written, or C<undef> if |
768 | unsuccessful. |
769 | |
770 | =head2 write |
771 | |
772 | Usage is |
773 | |
774 | $z->write $data |
775 | $z->write $data, $length |
776 | $z->write $data, $length, $offset |
777 | |
778 | Compresses and outputs the contents of the C<$data> parameter. |
779 | |
780 | Returns the number of uncompressed bytes written, or C<undef> if |
781 | unsuccessful. |
782 | |
783 | =head2 flush |
784 | |
785 | Usage is |
786 | |
787 | $z->flush; |
788 | $z->flush($flush_type); |
789 | flush $z ; |
790 | flush $z $flush_type; |
791 | |
792 | Flushes any pending compressed data to the output file/buffer. |
793 | |
794 | This method takes an optional parameter, C<$flush_type>, that controls |
795 | how the flushing will be carried out. By default the C<$flush_type> |
796 | used is C<Z_FINISH>. Other valid values for C<$flush_type> are |
797 | C<Z_NO_FLUSH>, C<Z_SYNC_FLUSH>, C<Z_FULL_FLUSH> and C<Z_BLOCK>. It is |
798 | strongly recommended that you only set the C<flush_type> parameter if |
799 | you fully understand the implications of what it does - overuse of C<flush> |
800 | can seriously degrade the level of compression achieved. See the C<zlib> |
801 | documentation for details. |
802 | |
803 | Returns true on success. |
804 | |
805 | |
806 | =head2 tell |
807 | |
808 | Usage is |
809 | |
810 | $z->tell() |
811 | tell $z |
812 | |
813 | Returns the uncompressed file offset. |
814 | |
815 | =head2 eof |
816 | |
817 | Usage is |
818 | |
819 | $z->eof(); |
820 | eof($z); |
821 | |
822 | |
823 | |
824 | Returns true if the C<close> method has been called. |
825 | |
826 | |
827 | |
828 | =head2 seek |
829 | |
830 | $z->seek($position, $whence); |
831 | seek($z, $position, $whence); |
832 | |
833 | |
834 | |
835 | |
836 | Provides a sub-set of the C<seek> functionality, with the restriction |
837 | that it is only legal to seek forward in the output file/buffer. |
838 | It is a fatal error to attempt to seek backward. |
839 | |
840 | Empty parts of the file/buffer will have NULL (0x00) bytes written to them. |
841 | |
842 | |
843 | |
844 | The C<$whence> parameter takes one the usual values, namely SEEK_SET, |
845 | SEEK_CUR or SEEK_END. |
846 | |
847 | Returns 1 on success, 0 on failure. |
848 | |
849 | =head2 binmode |
850 | |
851 | Usage is |
852 | |
853 | $z->binmode |
854 | binmode $z ; |
855 | |
856 | This is a noop provided for completeness. |
857 | |
858 | =head2 fileno |
859 | |
860 | $z->fileno() |
861 | fileno($z) |
862 | |
863 | If the C<$z> object is associated with a file, this method will return |
864 | the underlying filehandle. |
865 | |
866 | If the C<$z> object is is associated with a buffer, this method will |
867 | return undef. |
868 | |
869 | =head2 close |
870 | |
871 | $z->close() ; |
872 | close $z ; |
873 | |
874 | |
875 | |
876 | Flushes any pending compressed data and then closes the output file/buffer. |
877 | |
878 | |
879 | |
880 | For most versions of Perl this method will be automatically invoked if |
881 | the IO::Compress::RawDeflate object is destroyed (either explicitly or by the |
882 | variable with the reference to the object going out of scope). The |
883 | exceptions are Perl versions 5.005 through 5.00504 and 5.8.0. In |
884 | these cases, the C<close> method will be called automatically, but |
885 | not until global destruction of all live objects when the program is |
886 | terminating. |
887 | |
888 | Therefore, if you want your scripts to be able to run on all versions |
889 | of Perl, you should call C<close> explicitly and not rely on automatic |
890 | closing. |
891 | |
892 | Returns true on success, otherwise 0. |
893 | |
894 | If the C<AutoClose> option has been enabled when the IO::Compress::RawDeflate |
895 | object was created, and the object is associated with a file, the |
896 | underlying file will also be closed. |
897 | |
898 | |
899 | |
900 | |
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901 | =head2 newStream([OPTS]) |
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902 | |
903 | Usage is |
904 | |
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905 | $z->newStream( [OPTS] ) |
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906 | |
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907 | Closes the current compressed data stream and starts a new one. |
908 | |
909 | OPTS consists of the following sub-set of the the options that are |
910 | available when creating the C<$z> object, |
911 | |
912 | =over 5 |
913 | |
914 | =item * Level |
915 | |
916 | =item * TODO |
917 | |
918 | =back |
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919 | |
920 | =head2 deflateParams |
921 | |
922 | Usage is |
923 | |
924 | $z->deflateParams |
925 | |
926 | TODO |
927 | |
928 | =head1 Importing |
929 | |
930 | A number of symbolic constants are required by some methods in |
931 | C<IO::Compress::RawDeflate>. None are imported by default. |
932 | |
933 | =over 5 |
934 | |
935 | =item :all |
936 | |
937 | Imports C<rawdeflate>, C<$RawDeflateError> and all symbolic |
938 | constants that can be used by C<IO::Compress::RawDeflate>. Same as doing this |
939 | |
940 | use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError :constants) ; |
941 | |
942 | =item :constants |
943 | |
944 | Import all symbolic constants. Same as doing this |
945 | |
946 | use IO::Compress::RawDeflate qw(:flush :level :strategy) ; |
947 | |
948 | =item :flush |
949 | |
950 | These symbolic constants are used by the C<flush> method. |
951 | |
952 | Z_NO_FLUSH |
953 | Z_PARTIAL_FLUSH |
954 | Z_SYNC_FLUSH |
955 | Z_FULL_FLUSH |
956 | Z_FINISH |
957 | Z_BLOCK |
958 | |
959 | |
960 | =item :level |
961 | |
962 | These symbolic constants are used by the C<Level> option in the constructor. |
963 | |
964 | Z_NO_COMPRESSION |
965 | Z_BEST_SPEED |
966 | Z_BEST_COMPRESSION |
967 | Z_DEFAULT_COMPRESSION |
968 | |
969 | |
970 | =item :strategy |
971 | |
972 | These symbolic constants are used by the C<Strategy> option in the constructor. |
973 | |
974 | Z_FILTERED |
975 | Z_HUFFMAN_ONLY |
976 | Z_RLE |
977 | Z_FIXED |
978 | Z_DEFAULT_STRATEGY |
979 | |
980 | =back |
981 | |
982 | For |
983 | |
984 | =head1 EXAMPLES |
985 | |
986 | TODO |
987 | |
988 | |
989 | |
990 | |
991 | |
992 | |
993 | =head1 SEE ALSO |
994 | |
995 | L<Compress::Zlib>, L<IO::Compress::Gzip>, L<IO::Uncompress::Gunzip>, L<IO::Compress::Deflate>, L<IO::Uncompress::Inflate>, L<IO::Uncompress::RawInflate>, L<IO::Uncompress::AnyInflate> |
996 | |
997 | L<Compress::Zlib::FAQ|Compress::Zlib::FAQ> |
998 | |
999 | L<File::GlobMapper|File::GlobMapper>, L<Archive::Tar|Archive::Zip>, |
1000 | L<IO::Zlib|IO::Zlib> |
1001 | |
1002 | For RFC 1950, 1951 and 1952 see |
1003 | F<http://www.faqs.org/rfcs/rfc1950.html>, |
1004 | F<http://www.faqs.org/rfcs/rfc1951.html> and |
1005 | F<http://www.faqs.org/rfcs/rfc1952.html> |
1006 | |
1007 | The primary site for the gzip program is F<http://www.gzip.org>. |
1008 | |
1009 | =head1 AUTHOR |
1010 | |
1011 | The I<IO::Compress::RawDeflate> module was written by Paul Marquess, |
1012 | F<pmqs@cpan.org>. The latest copy of the module can be |
1013 | found on CPAN in F<modules/by-module/Compress/Compress-Zlib-x.x.tar.gz>. |
1014 | |
1015 | The I<zlib> compression library was written by Jean-loup Gailly |
1016 | F<gzip@prep.ai.mit.edu> and Mark Adler F<madler@alumni.caltech.edu>. |
1017 | |
1018 | The primary site for the I<zlib> compression library is |
1019 | F<http://www.zlib.org>. |
1020 | |
1021 | =head1 MODIFICATION HISTORY |
1022 | |
1023 | See the Changes file. |
1024 | |
1025 | =head1 COPYRIGHT AND LICENSE |
1026 | |
1027 | |
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1028 | Copyright (c) 2005-2006 Paul Marquess. All rights reserved. |
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1029 | This program is free software; you can redistribute it and/or |
1030 | modify it under the same terms as Perl itself. |
1031 | |
1032 | |
1033 | |
1034 | |