1014 lines
26 KiB
Perl
1014 lines
26 KiB
Perl
package IO::Compress::RawDeflate ;
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# create RFC1951
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#
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use strict ;
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use warnings;
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use bytes;
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use IO::Compress::Base 2.100 ;
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use IO::Compress::Base::Common 2.100 qw(:Status :Parse);
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use IO::Compress::Adapter::Deflate 2.100 ;
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use Compress::Raw::Zlib 2.100 qw(Z_DEFLATED Z_DEFAULT_COMPRESSION Z_DEFAULT_STRATEGY);
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require Exporter ;
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our ($VERSION, @ISA, @EXPORT_OK, %DEFLATE_CONSTANTS, %EXPORT_TAGS, $RawDeflateError);
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$VERSION = '2.100';
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$RawDeflateError = '';
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@ISA = qw(IO::Compress::Base Exporter);
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@EXPORT_OK = qw( $RawDeflateError rawdeflate ) ;
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push @EXPORT_OK, @IO::Compress::Adapter::Deflate::EXPORT_OK ;
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%EXPORT_TAGS = %IO::Compress::Adapter::Deflate::DEFLATE_CONSTANTS;
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{
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my %seen;
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foreach (keys %EXPORT_TAGS )
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{
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push @{$EXPORT_TAGS{constants}},
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grep { !$seen{$_}++ }
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@{ $EXPORT_TAGS{$_} }
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}
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$EXPORT_TAGS{all} = $EXPORT_TAGS{constants} ;
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}
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%DEFLATE_CONSTANTS = %EXPORT_TAGS;
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#push @{ $EXPORT_TAGS{all} }, @EXPORT_OK ;
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Exporter::export_ok_tags('all');
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sub new
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{
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my $class = shift ;
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my $obj = IO::Compress::Base::Common::createSelfTiedObject($class, \$RawDeflateError);
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return $obj->_create(undef, @_);
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}
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sub rawdeflate
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{
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my $obj = IO::Compress::Base::Common::createSelfTiedObject(undef, \$RawDeflateError);
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return $obj->_def(@_);
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}
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sub ckParams
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{
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my $self = shift ;
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my $got = shift;
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return 1 ;
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}
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sub mkComp
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{
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my $self = shift ;
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my $got = shift ;
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my ($obj, $errstr, $errno) = IO::Compress::Adapter::Deflate::mkCompObject(
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$got->getValue('crc32'),
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$got->getValue('adler32'),
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$got->getValue('level'),
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$got->getValue('strategy')
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);
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return $self->saveErrorString(undef, $errstr, $errno)
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if ! defined $obj;
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return $obj;
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}
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sub mkHeader
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{
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my $self = shift ;
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return '';
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}
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sub mkTrailer
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{
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my $self = shift ;
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return '';
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}
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sub mkFinalTrailer
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{
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return '';
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}
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#sub newHeader
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#{
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# my $self = shift ;
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# return '';
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#}
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sub getExtraParams
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{
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my $self = shift ;
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return getZlibParams();
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}
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our %PARAMS = (
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#'method' => [IO::Compress::Base::Common::Parse_unsigned, Z_DEFLATED],
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'level' => [IO::Compress::Base::Common::Parse_signed, Z_DEFAULT_COMPRESSION],
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'strategy' => [IO::Compress::Base::Common::Parse_signed, Z_DEFAULT_STRATEGY],
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'crc32' => [IO::Compress::Base::Common::Parse_boolean, 0],
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'adler32' => [IO::Compress::Base::Common::Parse_boolean, 0],
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'merge' => [IO::Compress::Base::Common::Parse_boolean, 0],
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);
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sub getZlibParams
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{
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return %PARAMS;
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}
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sub getInverseClass
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{
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no warnings 'once';
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return ('IO::Uncompress::RawInflate',
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\$IO::Uncompress::RawInflate::RawInflateError);
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}
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sub getFileInfo
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{
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my $self = shift ;
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my $params = shift;
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my $file = shift ;
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}
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use Fcntl qw(SEEK_SET);
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sub createMerge
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{
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my $self = shift ;
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my $outValue = shift ;
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my $outType = shift ;
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my ($invClass, $error_ref) = $self->getInverseClass();
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eval "require $invClass"
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or die "aaaahhhh" ;
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my $inf = $invClass->new( $outValue,
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Transparent => 0,
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#Strict => 1,
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AutoClose => 0,
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Scan => 1)
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or return $self->saveErrorString(undef, "Cannot create InflateScan object: $$error_ref" ) ;
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my $end_offset = 0;
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$inf->scan()
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or return $self->saveErrorString(undef, "Error Scanning: $$error_ref", $inf->errorNo) ;
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$inf->zap($end_offset)
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or return $self->saveErrorString(undef, "Error Zapping: $$error_ref", $inf->errorNo) ;
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my $def = *$self->{Compress} = $inf->createDeflate();
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*$self->{Header} = *$inf->{Info}{Header};
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*$self->{UnCompSize} = *$inf->{UnCompSize}->clone();
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*$self->{CompSize} = *$inf->{CompSize}->clone();
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# TODO -- fix this
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#*$self->{CompSize} = U64->new(0, *$self->{UnCompSize_32bit});
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if ( $outType eq 'buffer')
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{ substr( ${ *$self->{Buffer} }, $end_offset) = '' }
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elsif ($outType eq 'handle' || $outType eq 'filename') {
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*$self->{FH} = *$inf->{FH} ;
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delete *$inf->{FH};
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*$self->{FH}->flush() ;
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*$self->{Handle} = 1 if $outType eq 'handle';
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#seek(*$self->{FH}, $end_offset, SEEK_SET)
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*$self->{FH}->seek($end_offset, SEEK_SET)
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or return $self->saveErrorString(undef, $!, $!) ;
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}
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return $def ;
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}
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#### zlib specific methods
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sub deflateParams
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{
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my $self = shift ;
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my $level = shift ;
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my $strategy = shift ;
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my $status = *$self->{Compress}->deflateParams(Level => $level, Strategy => $strategy) ;
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return $self->saveErrorString(0, *$self->{Compress}{Error}, *$self->{Compress}{ErrorNo})
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if $status == STATUS_ERROR;
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return 1;
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}
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1;
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__END__
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=head1 NAME
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IO::Compress::RawDeflate - Write RFC 1951 files/buffers
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=head1 SYNOPSIS
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use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ;
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my $status = rawdeflate $input => $output [,OPTS]
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or die "rawdeflate failed: $RawDeflateError\n";
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my $z = IO::Compress::RawDeflate->new( $output [,OPTS] )
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or die "rawdeflate failed: $RawDeflateError\n";
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$z->print($string);
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$z->printf($format, $string);
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$z->write($string);
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$z->syswrite($string [, $length, $offset]);
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$z->flush();
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$z->tell();
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$z->eof();
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$z->seek($position, $whence);
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$z->binmode();
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$z->fileno();
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$z->opened();
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$z->autoflush();
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$z->input_line_number();
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$z->newStream( [OPTS] );
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$z->deflateParams();
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$z->close() ;
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$RawDeflateError ;
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# IO::File mode
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print $z $string;
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printf $z $format, $string;
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tell $z
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eof $z
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seek $z, $position, $whence
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binmode $z
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fileno $z
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close $z ;
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=head1 DESCRIPTION
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This module provides a Perl interface that allows writing compressed
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data to files or buffer as defined in RFC 1951.
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Note that RFC 1951 data is not a good choice of compression format
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to use in isolation, especially if you want to auto-detect it.
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For reading RFC 1951 files/buffers, see the companion module
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L<IO::Uncompress::RawInflate|IO::Uncompress::RawInflate>.
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=head1 Functional Interface
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A top-level function, C<rawdeflate>, is provided to carry out
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"one-shot" compression between buffers and/or files. For finer
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control over the compression process, see the L</"OO Interface">
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section.
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use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ;
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rawdeflate $input_filename_or_reference => $output_filename_or_reference [,OPTS]
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or die "rawdeflate failed: $RawDeflateError\n";
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The functional interface needs Perl5.005 or better.
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=head2 rawdeflate $input_filename_or_reference => $output_filename_or_reference [, OPTS]
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C<rawdeflate> expects at least two parameters,
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C<$input_filename_or_reference> and C<$output_filename_or_reference>
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and zero or more optional parameters (see L</Optional Parameters>)
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=head3 The C<$input_filename_or_reference> parameter
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The parameter, C<$input_filename_or_reference>, is used to define the
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source of the uncompressed data.
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It can take one of the following forms:
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=over 5
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=item A filename
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If the C<$input_filename_or_reference> parameter is a simple scalar, it is
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assumed to be a filename. This file will be opened for reading and the
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input data will be read from it.
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=item A filehandle
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If the C<$input_filename_or_reference> parameter is a filehandle, the input
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data will be read from it. The string '-' can be used as an alias for
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standard input.
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=item A scalar reference
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If C<$input_filename_or_reference> is a scalar reference, the input data
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will be read from C<$$input_filename_or_reference>.
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=item An array reference
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If C<$input_filename_or_reference> is an array reference, each element in
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the array must be a filename.
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The input data will be read from each file in turn.
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The complete array will be walked to ensure that it only
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contains valid filenames before any data is compressed.
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=item An Input FileGlob string
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If C<$input_filename_or_reference> is a string that is delimited by the
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characters "<" and ">" C<rawdeflate> will assume that it is an
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I<input fileglob string>. The input is the list of files that match the
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fileglob.
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See L<File::GlobMapper|File::GlobMapper> for more details.
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=back
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If the C<$input_filename_or_reference> parameter is any other type,
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C<undef> will be returned.
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=head3 The C<$output_filename_or_reference> parameter
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The parameter C<$output_filename_or_reference> is used to control the
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destination of the compressed data. This parameter can take one of
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these forms.
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=over 5
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=item A filename
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If the C<$output_filename_or_reference> parameter is a simple scalar, it is
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assumed to be a filename. This file will be opened for writing and the
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compressed data will be written to it.
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=item A filehandle
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If the C<$output_filename_or_reference> parameter is a filehandle, the
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compressed data will be written to it. The string '-' can be used as
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an alias for standard output.
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=item A scalar reference
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If C<$output_filename_or_reference> is a scalar reference, the
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compressed data will be stored in C<$$output_filename_or_reference>.
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=item An Array Reference
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If C<$output_filename_or_reference> is an array reference,
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the compressed data will be pushed onto the array.
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=item An Output FileGlob
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If C<$output_filename_or_reference> is a string that is delimited by the
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characters "<" and ">" C<rawdeflate> will assume that it is an
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I<output fileglob string>. The output is the list of files that match the
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fileglob.
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When C<$output_filename_or_reference> is an fileglob string,
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C<$input_filename_or_reference> must also be a fileglob string. Anything
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else is an error.
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See L<File::GlobMapper|File::GlobMapper> for more details.
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=back
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If the C<$output_filename_or_reference> parameter is any other type,
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C<undef> will be returned.
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=head2 Notes
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When C<$input_filename_or_reference> maps to multiple files/buffers and
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C<$output_filename_or_reference> is a single
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file/buffer the input files/buffers will be stored
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in C<$output_filename_or_reference> as a concatenated series of compressed data streams.
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=head2 Optional Parameters
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The optional parameters for the one-shot function C<rawdeflate>
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are (for the most part) identical to those used with the OO interface defined in the
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L</"Constructor Options"> section. The exceptions are listed below
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=over 5
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=item C<< AutoClose => 0|1 >>
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This option applies to any input or output data streams to
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C<rawdeflate> that are filehandles.
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If C<AutoClose> is specified, and the value is true, it will result in all
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input and/or output filehandles being closed once C<rawdeflate> has
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completed.
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This parameter defaults to 0.
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=item C<< BinModeIn => 0|1 >>
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This option is now a no-op. All files will be read in binmode.
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=item C<< Append => 0|1 >>
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The behaviour of this option is dependent on the type of output data
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stream.
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=over 5
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=item * A Buffer
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If C<Append> is enabled, all compressed data will be append to the end of
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the output buffer. Otherwise the output buffer will be cleared before any
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compressed data is written to it.
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=item * A Filename
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If C<Append> is enabled, the file will be opened in append mode. Otherwise
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the contents of the file, if any, will be truncated before any compressed
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data is written to it.
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=item * A Filehandle
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If C<Append> is enabled, the filehandle will be positioned to the end of
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the file via a call to C<seek> before any compressed data is
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written to it. Otherwise the file pointer will not be moved.
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=back
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When C<Append> is specified, and set to true, it will I<append> all compressed
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data to the output data stream.
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So when the output is a filehandle it will carry out a seek to the eof
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before writing any compressed data. If the output is a filename, it will be opened for
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appending. If the output is a buffer, all compressed data will be
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appended to the existing buffer.
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Conversely when C<Append> is not specified, or it is present and is set to
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false, it will operate as follows.
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When the output is a filename, it will truncate the contents of the file
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before writing any compressed data. If the output is a filehandle
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its position will not be changed. If the output is a buffer, it will be
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wiped before any compressed data is output.
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Defaults to 0.
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=back
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=head2 Examples
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Here are a few example that show the capabilities of the module.
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=head3 Streaming
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This very simple command line example demonstrates the streaming capabilities of the module.
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The code reads data from STDIN, compresses it, and writes the compressed data to STDOUT.
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$ echo hello world | perl -MIO::Compress::RawDeflate=rawdeflate -e 'rawdeflate \*STDIN => \*STDOUT' >output.1951
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The special filename "-" can be used as a standin for both C<\*STDIN> and C<\*STDOUT>,
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so the above can be rewritten as
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$ echo hello world | perl -MIO::Compress::RawDeflate=rawdeflate -e 'rawdeflate "-" => "-"' >output.1951
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=head3 Compressing a file from the filesystem
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To read the contents of the file C<file1.txt> and write the compressed
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data to the file C<file1.txt.1951>.
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use strict ;
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use warnings ;
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use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ;
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my $input = "file1.txt";
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rawdeflate $input => "$input.1951"
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or die "rawdeflate failed: $RawDeflateError\n";
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=head3 Reading from a Filehandle and writing to an in-memory buffer
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To read from an existing Perl filehandle, C<$input>, and write the
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compressed data to a buffer, C<$buffer>.
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use strict ;
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use warnings ;
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use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ;
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use IO::File ;
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my $input = IO::File->new( "<file1.txt" )
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or die "Cannot open 'file1.txt': $!\n" ;
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my $buffer ;
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rawdeflate $input => \$buffer
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or die "rawdeflate failed: $RawDeflateError\n";
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=head3 Compressing multiple files
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To compress all files in the directory "/my/home" that match "*.txt"
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and store the compressed data in the same directory
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use strict ;
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use warnings ;
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use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ;
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rawdeflate '</my/home/*.txt>' => '<*.1951>'
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or die "rawdeflate failed: $RawDeflateError\n";
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and if you want to compress each file one at a time, this will do the trick
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use strict ;
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use warnings ;
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use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError) ;
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for my $input ( glob "/my/home/*.txt" )
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{
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my $output = "$input.1951" ;
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rawdeflate $input => $output
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or die "Error compressing '$input': $RawDeflateError\n";
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}
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=head1 OO Interface
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=head2 Constructor
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The format of the constructor for C<IO::Compress::RawDeflate> is shown below
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my $z = IO::Compress::RawDeflate->new( $output [,OPTS] )
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or die "IO::Compress::RawDeflate failed: $RawDeflateError\n";
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|
|
It returns an C<IO::Compress::RawDeflate> object on success and undef on failure.
|
|
The variable C<$RawDeflateError> will contain an error message on failure.
|
|
|
|
If you are running Perl 5.005 or better the object, C<$z>, returned from
|
|
IO::Compress::RawDeflate 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<$output> parameter is any other type, C<IO::Compress::RawDeflate>::new will
|
|
return undef.
|
|
|
|
=head2 Constructor Options
|
|
|
|
C<OPTS> is any combination of zero or more the following options:
|
|
|
|
=over 5
|
|
|
|
=item C<< AutoClose => 0|1 >>
|
|
|
|
This option is only valid when the C<$output> parameter is a filehandle. If
|
|
specified, and the value is true, it will result in the C<$output> being
|
|
closed once either the C<close> method is called or the C<IO::Compress::RawDeflate>
|
|
object is destroyed.
|
|
|
|
This parameter defaults to 0.
|
|
|
|
=item C<< Append => 0|1 >>
|
|
|
|
Opens C<$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 of 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<$output> is not an
|
|
RFC 1951 data stream.
|
|
|
|
There are a number of other limitations with the C<Merge> option:
|
|
|
|
=over 5
|
|
|
|
=item 1
|
|
|
|
This module needs to have been built with zlib 1.2.1 or better to work. A
|
|
fatal error will be thrown if C<Merge> is used with an older version of
|
|
zlib.
|
|
|
|
=item 2
|
|
|
|
If C<$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::RawDeflate> by default.
|
|
|
|
use IO::Compress::RawDeflate qw(:strategy);
|
|
use IO::Compress::RawDeflate qw(:constants);
|
|
use IO::Compress::RawDeflate 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 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::RawDeflate 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::RawDeflate
|
|
object was created, and the object is associated with a file, the
|
|
underlying file will also be closed.
|
|
|
|
=head2 newStream([OPTS])
|
|
|
|
Usage is
|
|
|
|
$z->newStream( [OPTS] )
|
|
|
|
Closes the current compressed data stream and starts a new one.
|
|
|
|
OPTS consists of any of the options that are available when creating
|
|
the C<$z> object.
|
|
|
|
See the L</"Constructor Options"> section for more details.
|
|
|
|
=head2 deflateParams
|
|
|
|
Usage is
|
|
|
|
$z->deflateParams
|
|
|
|
TODO
|
|
|
|
=head1 Importing
|
|
|
|
A number of symbolic constants are required by some methods in
|
|
C<IO::Compress::RawDeflate>. None are imported by default.
|
|
|
|
=over 5
|
|
|
|
=item :all
|
|
|
|
Imports C<rawdeflate>, C<$RawDeflateError> and all symbolic
|
|
constants that can be used by C<IO::Compress::RawDeflate>. Same as doing this
|
|
|
|
use IO::Compress::RawDeflate qw(rawdeflate $RawDeflateError :constants) ;
|
|
|
|
=item :constants
|
|
|
|
Import all symbolic constants. Same as doing this
|
|
|
|
use IO::Compress::RawDeflate 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 SUPPORT
|
|
|
|
General feedback/questions/bug reports should be sent to
|
|
L<https://github.com/pmqs/IO-Compress/issues> (preferred) or
|
|
L<https://rt.cpan.org/Public/Dist/Display.html?Name=IO-Compress>.
|
|
|
|
=head1 SEE ALSO
|
|
|
|
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::Compress::Bzip2>, L<IO::Uncompress::Bunzip2>, L<IO::Compress::Lzma>, L<IO::Uncompress::UnLzma>, L<IO::Compress::Xz>, L<IO::Uncompress::UnXz>, L<IO::Compress::Lzip>, L<IO::Uncompress::UnLzip>, L<IO::Compress::Lzop>, L<IO::Uncompress::UnLzop>, L<IO::Compress::Lzf>, L<IO::Uncompress::UnLzf>, L<IO::Compress::Zstd>, L<IO::Uncompress::UnZstd>, L<IO::Uncompress::AnyInflate>, L<IO::Uncompress::AnyUncompress>
|
|
|
|
L<IO::Compress::FAQ|IO::Compress::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
|
|
L<http://www.faqs.org/rfcs/rfc1950.html>,
|
|
L<http://www.faqs.org/rfcs/rfc1951.html> and
|
|
L<http://www.faqs.org/rfcs/rfc1952.html>
|
|
|
|
The I<zlib> compression library was written by Jean-loup Gailly
|
|
C<gzip@prep.ai.mit.edu> and Mark Adler C<madler@alumni.caltech.edu>.
|
|
|
|
The primary site for the I<zlib> compression library is
|
|
L<http://www.zlib.org>.
|
|
|
|
The primary site for gzip is L<http://www.gzip.org>.
|
|
|
|
=head1 AUTHOR
|
|
|
|
This module was written by Paul Marquess, C<pmqs@cpan.org>.
|
|
|
|
=head1 MODIFICATION HISTORY
|
|
|
|
See the Changes file.
|
|
|
|
=head1 COPYRIGHT AND LICENSE
|
|
|
|
Copyright (c) 2005-2021 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.
|