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diff --git a/ext/IO-Compress/lib/IO/Compress/Deflate.pm b/ext/IO-Compress/lib/IO/Compress/Deflate.pm new file mode 100644 index 0000000000..05466f3a66 --- /dev/null +++ b/ext/IO-Compress/lib/IO/Compress/Deflate.pm @@ -0,0 +1,889 @@ +package IO::Compress::Deflate ; + +use strict ; +use warnings; +use bytes; + +require Exporter ; + +use IO::Compress::RawDeflate 2.017 ; + +use Compress::Raw::Zlib 2.017 ; +use IO::Compress::Zlib::Constants 2.017 ; +use IO::Compress::Base::Common 2.017 qw(createSelfTiedObject); + + +our ($VERSION, @ISA, @EXPORT_OK, %EXPORT_TAGS, $DeflateError); + +$VERSION = '2.017'; +$DeflateError = ''; + +@ISA = qw(Exporter IO::Compress::RawDeflate); +@EXPORT_OK = qw( $DeflateError deflate ) ; +%EXPORT_TAGS = %IO::Compress::RawDeflate::DEFLATE_CONSTANTS ; +push @{ $EXPORT_TAGS{all} }, @EXPORT_OK ; +Exporter::export_ok_tags('all'); + + +sub new +{ + my $class = shift ; + + my $obj = createSelfTiedObject($class, \$DeflateError); + return $obj->_create(undef, @_); +} + +sub deflate +{ + my $obj = createSelfTiedObject(undef, \$DeflateError); + return $obj->_def(@_); +} + + +sub bitmask($$$$) +{ + my $into = shift ; + my $value = shift ; + my $offset = shift ; + my $mask = shift ; + + return $into | (($value & $mask) << $offset ) ; +} + +sub mkDeflateHdr($$$;$) +{ + my $method = shift ; + my $cinfo = shift; + my $level = shift; + my $fdict_adler = shift ; + + my $cmf = 0; + my $flg = 0; + my $fdict = 0; + $fdict = 1 if defined $fdict_adler; + + $cmf = bitmask($cmf, $method, ZLIB_CMF_CM_OFFSET, ZLIB_CMF_CM_BITS); + $cmf = bitmask($cmf, $cinfo, ZLIB_CMF_CINFO_OFFSET, ZLIB_CMF_CINFO_BITS); + + $flg = bitmask($flg, $fdict, ZLIB_FLG_FDICT_OFFSET, ZLIB_FLG_FDICT_BITS); + $flg = bitmask($flg, $level, ZLIB_FLG_LEVEL_OFFSET, ZLIB_FLG_LEVEL_BITS); + + my $fcheck = 31 - ($cmf * 256 + $flg) % 31 ; + $flg = bitmask($flg, $fcheck, ZLIB_FLG_FCHECK_OFFSET, ZLIB_FLG_FCHECK_BITS); + + my $hdr = pack("CC", $cmf, $flg) ; + $hdr .= pack("N", $fdict_adler) if $fdict ; + + return $hdr; +} + +sub mkHeader +{ + my $self = shift ; + my $param = shift ; + + my $level = $param->value('Level'); + my $strategy = $param->value('Strategy'); + + my $lflag ; + $level = 6 + if $level == Z_DEFAULT_COMPRESSION ; + + if (ZLIB_VERNUM >= 0x1210) + { + if ($strategy >= Z_HUFFMAN_ONLY || $level < 2) + { $lflag = ZLIB_FLG_LEVEL_FASTEST } + elsif ($level < 6) + { $lflag = ZLIB_FLG_LEVEL_FAST } + elsif ($level == 6) + { $lflag = ZLIB_FLG_LEVEL_DEFAULT } + else + { $lflag = ZLIB_FLG_LEVEL_SLOWEST } + } + else + { + $lflag = ($level - 1) >> 1 ; + $lflag = 3 if $lflag > 3 ; + } + + #my $wbits = (MAX_WBITS - 8) << 4 ; + my $wbits = 7; + mkDeflateHdr(ZLIB_CMF_CM_DEFLATED, $wbits, $lflag); +} + +sub ckParams +{ + my $self = shift ; + my $got = shift; + + $got->value('ADLER32' => 1); + return 1 ; +} + + +sub mkTrailer +{ + my $self = shift ; + return pack("N", *$self->{Compress}->adler32()) ; +} + +sub mkFinalTrailer +{ + return ''; +} + +#sub newHeader +#{ +# my $self = shift ; +# return *$self->{Header}; +#} + +sub getExtraParams +{ + my $self = shift ; + return $self->getZlibParams(), +} + +sub getInverseClass +{ + return ('IO::Uncompress::Inflate', + \$IO::Uncompress::Inflate::InflateError); +} + +sub getFileInfo +{ + my $self = shift ; + my $params = shift; + my $file = shift ; + +} + + + +1; + +__END__ + +=head1 NAME + +IO::Compress::Deflate - Write RFC 1950 files/buffers + + + +=head1 SYNOPSIS + + use IO::Compress::Deflate qw(deflate $DeflateError) ; + + my $status = deflate $input => $output [,OPTS] + or die "deflate failed: $DeflateError\n"; + + my $z = new IO::Compress::Deflate $output [,OPTS] + or die "deflate failed: $DeflateError\n"; + + $z->print($string); + $z->printf($format, $string); + $z->write($string); + $z->syswrite($string [, $length, $offset]); + $z->flush(); + $z->tell(); + $z->eof(); + $z->seek($position, $whence); + $z->binmode(); + $z->fileno(); + $z->opened(); + $z->autoflush(); + $z->input_line_number(); + $z->newStream( [OPTS] ); + + $z->deflateParams(); + + $z->close() ; + + $DeflateError ; + + # IO::File mode + + print $z $string; + printf $z $format, $string; + tell $z + eof $z + seek $z, $position, $whence + binmode $z + fileno $z + close $z ; + + +=head1 DESCRIPTION + +This module provides a Perl interface that allows writing compressed +data to files or buffer as defined in RFC 1950. + +For reading RFC 1950 files/buffers, see the companion module +L<IO::Uncompress::Inflate|IO::Uncompress::Inflate>. + +=head1 Functional Interface + +A top-level function, C<deflate>, is provided to carry out +"one-shot" compression between buffers and/or files. For finer +control over the compression process, see the L</"OO Interface"> +section. + + use IO::Compress::Deflate qw(deflate $DeflateError) ; + + deflate $input => $output [,OPTS] + or die "deflate failed: $DeflateError\n"; + +The functional interface needs Perl5.005 or better. + +=head2 deflate $input => $output [, OPTS] + +C<deflate> expects at least two parameters, C<$input> and C<$output>. + +=head3 The C<$input> parameter + +The parameter, C<$input>, is used to define the source of +the uncompressed data. + +It can take one of the following forms: + +=over 5 + +=item A filename + +If the C<$input> parameter is a simple scalar, it is assumed to be a +filename. This file will be opened for reading and the input data +will be read from it. + +=item A filehandle + +If the C<$input> parameter is a filehandle, the input data will be +read from it. +The string '-' can be used as an alias for standard input. + +=item A scalar reference + +If C<$input> is a scalar reference, the input data will be read +from C<$$input>. + +=item An array reference + +If C<$input> is an array reference, each element in the array must be a +filename. + +The input data will be read from each file in turn. + +The complete array will be walked to ensure that it only +contains valid filenames before any data is compressed. + +=item An Input FileGlob string + +If C<$input> is a string that is delimited by the characters "<" and ">" +C<deflate> will assume that it is an I<input fileglob string>. The +input is the list of files that match the fileglob. + +If the fileglob does not match any files ... + +See L<File::GlobMapper|File::GlobMapper> for more details. + +=back + +If the C<$input> parameter is any other type, C<undef> will be returned. + +=head3 The C<$output> parameter + +The parameter C<$output> is used to control the destination of the +compressed data. This parameter can take one of these forms. + +=over 5 + +=item A filename + +If the C<$output> parameter is a simple scalar, it is assumed to be a +filename. This file will be opened for writing and the compressed +data will be written to it. + +=item A filehandle + +If the C<$output> parameter is a filehandle, the compressed data +will be written to it. +The string '-' can be used as an alias for standard output. + +=item A scalar reference + +If C<$output> is a scalar reference, the compressed data will be +stored in C<$$output>. + +=item An Array Reference + +If C<$output> is an array reference, the compressed data will be +pushed onto the array. + +=item An Output FileGlob + +If C<$output> is a string that is delimited by the characters "<" and ">" +C<deflate> will assume that it is an I<output fileglob string>. The +output is the list of files that match the fileglob. + +When C<$output> is an fileglob string, C<$input> must also be a fileglob +string. Anything else is an error. + +=back + +If the C<$output> parameter is any other type, C<undef> will be returned. + +=head2 Notes + +When C<$input> maps to multiple files/buffers and C<$output> is a single +file/buffer the input files/buffers will be stored +in C<$output> as a concatenated series of compressed data streams. + +=head2 Optional Parameters + +Unless specified below, the optional parameters for C<deflate>, +C<OPTS>, are the same as those used with the OO interface defined in the +L</"Constructor Options"> section below. + +=over 5 + +=item C<< AutoClose => 0|1 >> + +This option applies to any input or output data streams to +C<deflate> that are filehandles. + +If C<AutoClose> is specified, and the value is true, it will result in all +input and/or output filehandles being closed once C<deflate> has +completed. + +This parameter defaults to 0. + +=item C<< BinModeIn => 0|1 >> + +When reading from a file or filehandle, set C<binmode> before reading. + +Defaults to 0. + +=item C<< Append => 0|1 >> + +TODO + +=back + +=head2 Examples + +To read the contents of the file C<file1.txt> and write the compressed +data to the file C<file1.txt.1950>. + + use strict ; + use warnings ; + use IO::Compress::Deflate qw(deflate $DeflateError) ; + + my $input = "file1.txt"; + deflate $input => "$input.1950" + or die "deflate failed: $DeflateError\n"; + +To read from an existing Perl filehandle, C<$input>, and write the +compressed data to a buffer, C<$buffer>. + + use strict ; + use warnings ; + use IO::Compress::Deflate qw(deflate $DeflateError) ; + use IO::File ; + + my $input = new IO::File "<file1.txt" + or die "Cannot open 'file1.txt': $!\n" ; + my $buffer ; + deflate $input => \$buffer + or die "deflate failed: $DeflateError\n"; + +To compress all files in the directory "/my/home" that match "*.txt" +and store the compressed data in the same directory + + use strict ; + use warnings ; + use IO::Compress::Deflate qw(deflate $DeflateError) ; + + deflate '</my/home/*.txt>' => '<*.1950>' + or die "deflate failed: $DeflateError\n"; + +and if you want to compress each file one at a time, this will do the trick + + use strict ; + use warnings ; + use IO::Compress::Deflate qw(deflate $DeflateError) ; + + for my $input ( glob "/my/home/*.txt" ) + { + my $output = "$input.1950" ; + deflate $input => $output + or die "Error compressing '$input': $DeflateError\n"; + } + +=head1 OO Interface + +=head2 Constructor + +The format of the constructor for C<IO::Compress::Deflate> is shown below + + my $z = new IO::Compress::Deflate $output [,OPTS] + or die "IO::Compress::Deflate failed: $DeflateError\n"; + +It returns an C<IO::Compress::Deflate> object on success and undef on failure. +The variable C<$DeflateError> will contain an error message on failure. + +If you are running Perl 5.005 or better the object, C<$z>, returned from +IO::Compress::Deflate can be used exactly like an L<IO::File|IO::File> filehandle. +This means that all normal output file operations can be carried out +with C<$z>. +For example, to write to a compressed file/buffer you can use either of +these forms + + $z->print("hello world\n"); + print $z "hello world\n"; + +The mandatory parameter C<$output> is used to control the destination +of the compressed data. This parameter can take one of these forms. + +=over 5 + +=item A filename + +If the C<$output> parameter is a simple scalar, it is assumed to be a +filename. This file will be opened for writing and the compressed data +will be written to it. + +=item A filehandle + +If the C<$output> parameter is a filehandle, the compressed data will be +written to it. +The string '-' can be used as an alias for standard output. + +=item A scalar reference + +If C<$output> is a scalar reference, the compressed data will be stored +in C<$$output>. + +=back + +If the C<$output> parameter is any other type, C<IO::Compress::Deflate>::new will +return undef. + +=head2 Constructor Options + +C<OPTS> is any combination of the following options: + +=over 5 + +=item C<< AutoClose => 0|1 >> + +This option is only valid when the C<$output> parameter is a filehandle. If +specified, and the value is true, it will result in the C<$output> being +closed once either the C<close> method is called or the C<IO::Compress::Deflate> +object is destroyed. + +This parameter defaults to 0. + +=item C<< Append => 0|1 >> + +Opens C<$output> in append mode. + +The behaviour of this option is dependent on the type of C<$output>. + +=over 5 + +=item * A Buffer + +If C<$output> is a buffer and C<Append> is enabled, all compressed data +will be append to the end if C<$output>. Otherwise C<$output> will be +cleared before any data is written to it. + +=item * A Filename + +If C<$output> is a filename and C<Append> is enabled, the file will be +opened in append mode. Otherwise the contents of the file, if any, will be +truncated before any compressed data is written to it. + +=item * A Filehandle + +If C<$output> is a filehandle, the file pointer will be positioned to the +end of the file via a call to C<seek> before any compressed data is written +to it. Otherwise the file pointer will not be moved. + +=back + +This parameter defaults to 0. + +=item C<< Merge => 0|1 >> + +This option is used to compress input data and append it to an existing +compressed data stream in C<$output>. The end result is a single compressed +data stream stored in C<$output>. + +It is a fatal error to attempt to use this option when C<$output> is not an +RFC 1950 data stream. + +There are a number of other limitations with the C<Merge> option: + +=over 5 + +=item 1 + +This module needs to have been built with zlib 1.2.1 or better to work. A +fatal error will be thrown if C<Merge> is used with an older version of +zlib. + +=item 2 + +If C<$output> is a file or a filehandle, it must be seekable. + +=back + +This parameter defaults to 0. + +=item -Level + +Defines the compression level used by zlib. The value should either be +a number between 0 and 9 (0 means no compression and 9 is maximum +compression), or one of the symbolic constants defined below. + + Z_NO_COMPRESSION + Z_BEST_SPEED + Z_BEST_COMPRESSION + Z_DEFAULT_COMPRESSION + +The default is Z_DEFAULT_COMPRESSION. + +Note, these constants are not imported by C<IO::Compress::Deflate> by default. + + use IO::Compress::Deflate qw(:strategy); + use IO::Compress::Deflate qw(:constants); + use IO::Compress::Deflate qw(:all); + +=item -Strategy + +Defines the strategy used to tune the compression. Use one of the symbolic +constants defined below. + + Z_FILTERED + Z_HUFFMAN_ONLY + Z_RLE + Z_FIXED + Z_DEFAULT_STRATEGY + +The default is Z_DEFAULT_STRATEGY. + +=item C<< Strict => 0|1 >> + +This is a placeholder option. + +=back + +=head2 Examples + +TODO + +=head1 Methods + +=head2 print + +Usage is + + $z->print($data) + print $z $data + +Compresses and outputs the contents of the C<$data> parameter. This +has the same behaviour as the C<print> built-in. + +Returns true if successful. + +=head2 printf + +Usage is + + $z->printf($format, $data) + printf $z $format, $data + +Compresses and outputs the contents of the C<$data> parameter. + +Returns true if successful. + +=head2 syswrite + +Usage is + + $z->syswrite $data + $z->syswrite $data, $length + $z->syswrite $data, $length, $offset + +Compresses and outputs the contents of the C<$data> parameter. + +Returns the number of uncompressed bytes written, or C<undef> if +unsuccessful. + +=head2 write + +Usage is + + $z->write $data + $z->write $data, $length + $z->write $data, $length, $offset + +Compresses and outputs the contents of the C<$data> parameter. + +Returns the number of uncompressed bytes written, or C<undef> if +unsuccessful. + +=head2 flush + +Usage is + + $z->flush; + $z->flush($flush_type); + +Flushes any pending compressed data to the output file/buffer. + +This method takes an optional parameter, C<$flush_type>, that controls +how the flushing will be carried out. By default the C<$flush_type> +used is C<Z_FINISH>. Other valid values for C<$flush_type> are +C<Z_NO_FLUSH>, C<Z_SYNC_FLUSH>, C<Z_FULL_FLUSH> and C<Z_BLOCK>. It is +strongly recommended that you only set the C<flush_type> parameter if +you fully understand the implications of what it does - overuse of C<flush> +can seriously degrade the level of compression achieved. See the C<zlib> +documentation for details. + +Returns true on success. + +=head2 tell + +Usage is + + $z->tell() + tell $z + +Returns the uncompressed file offset. + +=head2 eof + +Usage is + + $z->eof(); + eof($z); + +Returns true if the C<close> method has been called. + +=head2 seek + + $z->seek($position, $whence); + seek($z, $position, $whence); + +Provides a sub-set of the C<seek> functionality, with the restriction +that it is only legal to seek forward in the output file/buffer. +It is a fatal error to attempt to seek backward. + +Empty parts of the file/buffer will have NULL (0x00) bytes written to them. + +The C<$whence> parameter takes one the usual values, namely SEEK_SET, +SEEK_CUR or SEEK_END. + +Returns 1 on success, 0 on failure. + +=head2 binmode + +Usage is + + $z->binmode + binmode $z ; + +This is a noop provided for completeness. + +=head2 opened + + $z->opened() + +Returns true if the object currently refers to a opened file/buffer. + +=head2 autoflush + + my $prev = $z->autoflush() + my $prev = $z->autoflush(EXPR) + +If the C<$z> object is associated with a file or a filehandle, this method +returns the current autoflush setting for the underlying filehandle. If +C<EXPR> is present, and is non-zero, it will enable flushing after every +write/print operation. + +If C<$z> is associated with a buffer, this method has no effect and always +returns C<undef>. + +B<Note> that the special variable C<$|> B<cannot> be used to set or +retrieve the autoflush setting. + +=head2 input_line_number + + $z->input_line_number() + $z->input_line_number(EXPR) + +This method always returns C<undef> when compressing. + +=head2 fileno + + $z->fileno() + fileno($z) + +If the C<$z> object is associated with a file or a filehandle, C<fileno> +will return the underlying file descriptor. Once the C<close> method is +called C<fileno> will return C<undef>. + +If the C<$z> object is is associated with a buffer, this method will return +C<undef>. + +=head2 close + + $z->close() ; + close $z ; + +Flushes any pending compressed data and then closes the output file/buffer. + +For most versions of Perl this method will be automatically invoked if +the IO::Compress::Deflate object is destroyed (either explicitly or by the +variable with the reference to the object going out of scope). The +exceptions are Perl versions 5.005 through 5.00504 and 5.8.0. In +these cases, the C<close> method will be called automatically, but +not until global destruction of all live objects when the program is +terminating. + +Therefore, if you want your scripts to be able to run on all versions +of Perl, you should call C<close> explicitly and not rely on automatic +closing. + +Returns true on success, otherwise 0. + +If the C<AutoClose> option has been enabled when the IO::Compress::Deflate +object was created, and the object is associated with a file, the +underlying file will also be closed. + +=head2 newStream([OPTS]) + +Usage is + + $z->newStream( [OPTS] ) + +Closes the current compressed data stream and starts a new one. + +OPTS consists of any of the the options that are available when creating +the C<$z> object. + +See the L</"Constructor Options"> section for more details. + +=head2 deflateParams + +Usage is + + $z->deflateParams + +TODO + +=head1 Importing + +A number of symbolic constants are required by some methods in +C<IO::Compress::Deflate>. None are imported by default. + +=over 5 + +=item :all + +Imports C<deflate>, C<$DeflateError> and all symbolic +constants that can be used by C<IO::Compress::Deflate>. Same as doing this + + use IO::Compress::Deflate qw(deflate $DeflateError :constants) ; + +=item :constants + +Import all symbolic constants. Same as doing this + + use IO::Compress::Deflate qw(:flush :level :strategy) ; + +=item :flush + +These symbolic constants are used by the C<flush> method. + + Z_NO_FLUSH + Z_PARTIAL_FLUSH + Z_SYNC_FLUSH + Z_FULL_FLUSH + Z_FINISH + Z_BLOCK + +=item :level + +These symbolic constants are used by the C<Level> option in the constructor. + + Z_NO_COMPRESSION + Z_BEST_SPEED + Z_BEST_COMPRESSION + Z_DEFAULT_COMPRESSION + +=item :strategy + +These symbolic constants are used by the C<Strategy> option in the constructor. + + Z_FILTERED + Z_HUFFMAN_ONLY + Z_RLE + Z_FIXED + Z_DEFAULT_STRATEGY + + + + +=back + +=head1 EXAMPLES + +=head2 Apache::GZip Revisited + +See L<IO::Compress::FAQ|IO::Compress::FAQ/"Apache::GZip Revisited"> + + + +=head2 Working with Net::FTP + +See L<IO::Compress::FAQ|IO::Compress::FAQ/"Compressed files and Net::FTP"> + +=head1 SEE ALSO + +L<Compress::Zlib>, L<IO::Compress::Gzip>, L<IO::Uncompress::Gunzip>, 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::Compress::Lzf>, L<IO::Uncompress::UnLzf>, L<IO::Uncompress::AnyInflate>, L<IO::Uncompress::AnyUncompress> + +L<Compress::Zlib::FAQ|Compress::Zlib::FAQ> + +L<File::GlobMapper|File::GlobMapper>, L<Archive::Zip|Archive::Zip>, +L<Archive::Tar|Archive::Tar>, +L<IO::Zlib|IO::Zlib> + +For RFC 1950, 1951 and 1952 see +F<http://www.faqs.org/rfcs/rfc1950.html>, +F<http://www.faqs.org/rfcs/rfc1951.html> and +F<http://www.faqs.org/rfcs/rfc1952.html> + +The I<zlib> compression library was written by Jean-loup Gailly +F<gzip@prep.ai.mit.edu> and Mark Adler F<madler@alumni.caltech.edu>. + +The primary site for the I<zlib> compression library is +F<http://www.zlib.org>. + +The primary site for gzip is F<http://www.gzip.org>. + +=head1 AUTHOR + +This module was written by Paul Marquess, F<pmqs@cpan.org>. + +=head1 MODIFICATION HISTORY + +See the Changes file. + +=head1 COPYRIGHT AND LICENSE + +Copyright (c) 2005-2009 Paul Marquess. All rights reserved. + +This program is free software; you can redistribute it and/or +modify it under the same terms as Perl itself. + |