package IO::Uncompress::Bunzip2 ; use strict ; use warnings; use bytes; use IO::Compress::Base::Common 2.101 qw(:Status ); use IO::Uncompress::Base 2.101 ; use IO::Uncompress::Adapter::Bunzip2 2.101 ; require Exporter ; our ($VERSION, @ISA, @EXPORT_OK, %EXPORT_TAGS, $Bunzip2Error); $VERSION = '2.102'; $Bunzip2Error = ''; @ISA = qw(IO::Uncompress::Base Exporter); @EXPORT_OK = qw( $Bunzip2Error bunzip2 ) ; #%EXPORT_TAGS = %IO::Uncompress::Base::EXPORT_TAGS ; push @{ $EXPORT_TAGS{all} }, @EXPORT_OK ; #Exporter::export_ok_tags('all'); sub new { my $class = shift ; my $obj = IO::Compress::Base::Common::createSelfTiedObject($class, \$Bunzip2Error); $obj->_create(undef, 0, @_); } sub bunzip2 { my $obj = IO::Compress::Base::Common::createSelfTiedObject(undef, \$Bunzip2Error); return $obj->_inf(@_); } sub getExtraParams { return ( 'verbosity' => [IO::Compress::Base::Common::Parse_boolean, 0], 'small' => [IO::Compress::Base::Common::Parse_boolean, 0], ); } sub ckParams { my $self = shift ; my $got = shift ; return 1; } sub mkUncomp { my $self = shift ; my $got = shift ; my $magic = $self->ckMagic() or return 0; *$self->{Info} = $self->readHeader($magic) or return undef ; my $Small = $got->getValue('small'); my $Verbosity = $got->getValue('verbosity'); my ($obj, $errstr, $errno) = IO::Uncompress::Adapter::Bunzip2::mkUncompObject( $Small, $Verbosity); return $self->saveErrorString(undef, $errstr, $errno) if ! defined $obj; *$self->{Uncomp} = $obj; return 1; } sub ckMagic { my $self = shift; my $magic ; $self->smartReadExact(\$magic, 4); *$self->{HeaderPending} = $magic ; return $self->HeaderError("Header size is " . 4 . " bytes") if length $magic != 4; return $self->HeaderError("Bad Magic.") if ! isBzip2Magic($magic) ; *$self->{Type} = 'bzip2'; return $magic; } sub readHeader { my $self = shift; my $magic = shift ; $self->pushBack($magic); *$self->{HeaderPending} = ''; return { 'Type' => 'bzip2', 'FingerprintLength' => 4, 'HeaderLength' => 4, 'TrailerLength' => 0, 'Header' => '$magic' }; } sub chkTrailer { return STATUS_OK; } sub isBzip2Magic { my $buffer = shift ; return $buffer =~ /^BZh\d$/; } 1 ; __END__ =head1 NAME IO::Uncompress::Bunzip2 - Read bzip2 files/buffers =head1 SYNOPSIS use IO::Uncompress::Bunzip2 qw(bunzip2 $Bunzip2Error) ; my $status = bunzip2 $input => $output [,OPTS] or die "bunzip2 failed: $Bunzip2Error\n"; my $z = IO::Uncompress::Bunzip2->new( $input [OPTS] ) or die "bunzip2 failed: $Bunzip2Error\n"; $status = $z->read($buffer) $status = $z->read($buffer, $length) $status = $z->read($buffer, $length, $offset) $line = $z->getline() $char = $z->getc() $char = $z->ungetc() $char = $z->opened() $data = $z->trailingData() $status = $z->nextStream() $data = $z->getHeaderInfo() $z->tell() $z->seek($position, $whence) $z->binmode() $z->fileno() $z->eof() $z->close() $Bunzip2Error ; # IO::File mode <$z> read($z, $buffer); read($z, $buffer, $length); read($z, $buffer, $length, $offset); tell($z) seek($z, $position, $whence) binmode($z) fileno($z) eof($z) close($z) =head1 DESCRIPTION This module provides a Perl interface that allows the reading of bzip2 files/buffers. For writing bzip2 files/buffers, see the companion module IO::Compress::Bzip2. =head1 Functional Interface A top-level function, C, is provided to carry out "one-shot" uncompression between buffers and/or files. For finer control over the uncompression process, see the L section. use IO::Uncompress::Bunzip2 qw(bunzip2 $Bunzip2Error) ; bunzip2 $input_filename_or_reference => $output_filename_or_reference [,OPTS] or die "bunzip2 failed: $Bunzip2Error\n"; The functional interface needs Perl5.005 or better. =head2 bunzip2 $input_filename_or_reference => $output_filename_or_reference [, OPTS] C expects at least two parameters, C<$input_filename_or_reference> and C<$output_filename_or_reference> and zero or more optional parameters (see L) =head3 The C<$input_filename_or_reference> parameter The parameter, C<$input_filename_or_reference>, is used to define the source of the compressed data. It can take one of the following forms: =over 5 =item A filename If the C<$input_filename_or_reference> 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<$input_filename_or_reference> parameter is a filehandle, the input data will be read from it. The string '-' can be used as an alias for standard input. =item A scalar reference If C<$input_filename_or_reference> is a scalar reference, the input data will be read from C<$$input_filename_or_reference>. =item An array reference If C<$input_filename_or_reference> is an array reference, each element in the array must be a filename. The input data will be read from each file in turn. The complete array will be walked to ensure that it only contains valid filenames before any data is uncompressed. =item An Input FileGlob string If C<$input_filename_or_reference> is a string that is delimited by the characters "<" and ">" C will assume that it is an I. The input is the list of files that match the fileglob. See L for more details. =back If the C<$input_filename_or_reference> parameter is any other type, C will be returned. =head3 The C<$output_filename_or_reference> parameter The parameter C<$output_filename_or_reference> is used to control the destination of the uncompressed data. This parameter can take one of these forms. =over 5 =item A filename If the C<$output_filename_or_reference> parameter is a simple scalar, it is assumed to be a filename. This file will be opened for writing and the uncompressed data will be written to it. =item A filehandle If the C<$output_filename_or_reference> parameter is a filehandle, the uncompressed data will be written to it. The string '-' can be used as an alias for standard output. =item A scalar reference If C<$output_filename_or_reference> is a scalar reference, the uncompressed data will be stored in C<$$output_filename_or_reference>. =item An Array Reference If C<$output_filename_or_reference> is an array reference, the uncompressed data will be pushed onto the array. =item An Output FileGlob If C<$output_filename_or_reference> is a string that is delimited by the characters "<" and ">" C will assume that it is an I. The output is the list of files that match the fileglob. When C<$output_filename_or_reference> is an fileglob string, C<$input_filename_or_reference> must also be a fileglob string. Anything else is an error. See L for more details. =back If the C<$output_filename_or_reference> parameter is any other type, C will be returned. =head2 Notes When C<$input_filename_or_reference> maps to multiple compressed files/buffers and C<$output_filename_or_reference> is a single file/buffer, after uncompression C<$output_filename_or_reference> will contain a concatenation of all the uncompressed data from each of the input files/buffers. =head2 Optional Parameters The optional parameters for the one-shot function C are (for the most part) identical to those used with the OO interface defined in the L section. The exceptions are listed below =over 5 =item C<< AutoClose => 0|1 >> This option applies to any input or output data streams to C that are filehandles. If C is specified, and the value is true, it will result in all input and/or output filehandles being closed once C has completed. This parameter defaults to 0. =item C<< BinModeOut => 0|1 >> This option is now a no-op. All files will be written in binmode. =item C<< Append => 0|1 >> The behaviour of this option is dependent on the type of output data stream. =over 5 =item * A Buffer If C is enabled, all uncompressed data will be append to the end of the output buffer. Otherwise the output buffer will be cleared before any uncompressed data is written to it. =item * A Filename If C is enabled, the file will be opened in append mode. Otherwise the contents of the file, if any, will be truncated before any uncompressed data is written to it. =item * A Filehandle If C is enabled, the filehandle will be positioned to the end of the file via a call to C before any uncompressed data is written to it. Otherwise the file pointer will not be moved. =back When C is specified, and set to true, it will I all uncompressed data to the output data stream. So when the output is a filehandle it will carry out a seek to the eof before writing any uncompressed data. If the output is a filename, it will be opened for appending. If the output is a buffer, all uncompressed data will be appended to the existing buffer. Conversely when C is not specified, or it is present and is set to false, it will operate as follows. When the output is a filename, it will truncate the contents of the file before writing any uncompressed data. If the output is a filehandle its position will not be changed. If the output is a buffer, it will be wiped before any uncompressed data is output. Defaults to 0. =item C<< MultiStream => 0|1 >> If the input file/buffer contains multiple compressed data streams, this option will uncompress the whole lot as a single data stream. Defaults to 0. =item C<< TrailingData => $scalar >> Returns the data, if any, that is present immediately after the compressed data stream once uncompression is complete. This option can be used when there is useful information immediately following the compressed data stream, and you don't know the length of the compressed data stream. If the input is a buffer, C will return everything from the end of the compressed data stream to the end of the buffer. If the input is a filehandle, C will return the data that is left in the filehandle input buffer once the end of the compressed data stream has been reached. You can then use the filehandle to read the rest of the input file. Don't bother using C if the input is a filename. If you know the length of the compressed data stream before you start uncompressing, you can avoid having to use C by setting the C option. =back =head2 Examples To read the contents of the file C and write the uncompressed data to the file C. use strict ; use warnings ; use IO::Uncompress::Bunzip2 qw(bunzip2 $Bunzip2Error) ; my $input = "file1.txt.bz2"; my $output = "file1.txt"; bunzip2 $input => $output or die "bunzip2 failed: $Bunzip2Error\n"; To read from an existing Perl filehandle, C<$input>, and write the uncompressed data to a buffer, C<$buffer>. use strict ; use warnings ; use IO::Uncompress::Bunzip2 qw(bunzip2 $Bunzip2Error) ; use IO::File ; my $input = IO::File->new( " \$buffer or die "bunzip2 failed: $Bunzip2Error\n"; To uncompress all files in the directory "/my/home" that match "*.txt.bz2" and store the compressed data in the same directory use strict ; use warnings ; use IO::Uncompress::Bunzip2 qw(bunzip2 $Bunzip2Error) ; bunzip2 '' => '' or die "bunzip2 failed: $Bunzip2Error\n"; and if you want to compress each file one at a time, this will do the trick use strict ; use warnings ; use IO::Uncompress::Bunzip2 qw(bunzip2 $Bunzip2Error) ; for my $input ( glob "/my/home/*.txt.bz2" ) { my $output = $input; $output =~ s/.bz2// ; bunzip2 $input => $output or die "Error compressing '$input': $Bunzip2Error\n"; } =head1 OO Interface =head2 Constructor The format of the constructor for IO::Uncompress::Bunzip2 is shown below my $z = IO::Uncompress::Bunzip2->new( $input [OPTS] ) or die "IO::Uncompress::Bunzip2 failed: $Bunzip2Error\n"; Returns an C object on success and undef on failure. The variable C<$Bunzip2Error> will contain an error message on failure. If you are running Perl 5.005 or better the object, C<$z>, returned from IO::Uncompress::Bunzip2 can be used exactly like an L filehandle. This means that all normal input file operations can be carried out with C<$z>. For example, to read a line from a compressed file/buffer you can use either of these forms $line = $z->getline(); $line = <$z>; The mandatory parameter C<$input> is used to determine the source of the compressed data. This parameter can take one of three forms. =over 5 =item A filename If the C<$input> parameter is a scalar, it is assumed to be a filename. This file will be opened for reading and the compressed data will be read from it. =item A filehandle If the C<$input> parameter is a filehandle, the compressed data will be read from it. The string '-' can be used as an alias for standard input. =item A scalar reference If C<$input> is a scalar reference, the compressed data will be read from C<$$input>. =back =head2 Constructor Options The option names defined below are case insensitive and can be optionally prefixed by a '-'. So all of the following are valid -AutoClose -autoclose AUTOCLOSE autoclose OPTS is a combination of the following options: =over 5 =item C<< AutoClose => 0|1 >> This option is only valid when the C<$input> parameter is a filehandle. If specified, and the value is true, it will result in the file being closed once either the C method is called or the IO::Uncompress::Bunzip2 object is destroyed. This parameter defaults to 0. =item C<< MultiStream => 0|1 >> Allows multiple concatenated compressed streams to be treated as a single compressed stream. Decompression will stop once either the end of the file/buffer is reached, an error is encountered (premature eof, corrupt compressed data) or the end of a stream is not immediately followed by the start of another stream. This parameter defaults to 0. =item C<< Prime => $string >> This option will uncompress the contents of C<$string> before processing the input file/buffer. This option can be useful when the compressed data is embedded in another file/data structure and it is not possible to work out where the compressed data begins without having to read the first few bytes. If this is the case, the uncompression can be I with these bytes using this option. =item C<< Transparent => 0|1 >> If this option is set and the input file/buffer is not compressed data, the module will allow reading of it anyway. In addition, if the input file/buffer does contain compressed data and there is non-compressed data immediately following it, setting this option will make this module treat the whole file/buffer as a single data stream. This option defaults to 1. =item C<< BlockSize => $num >> When reading the compressed input data, IO::Uncompress::Bunzip2 will read it in blocks of C<$num> bytes. This option defaults to 4096. =item C<< InputLength => $size >> When present this option will limit the number of compressed bytes read from the input file/buffer to C<$size>. This option can be used in the situation where there is useful data directly after the compressed data stream and you know beforehand the exact length of the compressed data stream. This option is mostly used when reading from a filehandle, in which case the file pointer will be left pointing to the first byte directly after the compressed data stream. This option defaults to off. =item C<< Append => 0|1 >> This option controls what the C method does with uncompressed data. If set to 1, all uncompressed data will be appended to the output parameter of the C method. If set to 0, the contents of the output parameter of the C method will be overwritten by the uncompressed data. Defaults to 0. =item C<< Strict => 0|1 >> This option is a no-op. =item C<< Small => 0|1 >> When non-zero this options will make bzip2 use a decompression algorithm that uses less memory at the expense of increasing the amount of time taken for decompression. Default is 0. =back =head2 Examples TODO =head1 Methods =head2 read Usage is $status = $z->read($buffer) Reads a block of compressed data (the size of the compressed block is determined by the C option in the constructor), uncompresses it and writes any uncompressed data into C<$buffer>. If the C parameter is set in the constructor, the uncompressed data will be appended to the C<$buffer> parameter. Otherwise C<$buffer> will be overwritten. Returns the number of uncompressed bytes written to C<$buffer>, zero if eof or a negative number on error. =head2 read Usage is $status = $z->read($buffer, $length) $status = $z->read($buffer, $length, $offset) $status = read($z, $buffer, $length) $status = read($z, $buffer, $length, $offset) Attempt to read C<$length> bytes of uncompressed data into C<$buffer>. The main difference between this form of the C method and the previous one, is that this one will attempt to return I C<$length> bytes. The only circumstances that this function will not is if end-of-file or an IO error is encountered. Returns the number of uncompressed bytes written to C<$buffer>, zero if eof or a negative number on error. =head2 getline Usage is $line = $z->getline() $line = <$z> Reads a single line. This method fully supports the use of the variable C<$/> (or C<$INPUT_RECORD_SEPARATOR> or C<$RS> when C is in use) to determine what constitutes an end of line. Paragraph mode, record mode and file slurp mode are all supported. =head2 getc Usage is $char = $z->getc() Read a single character. =head2 ungetc Usage is $char = $z->ungetc($string) =head2 getHeaderInfo Usage is $hdr = $z->getHeaderInfo(); @hdrs = $z->getHeaderInfo(); This method returns either a hash reference (in scalar context) or a list or hash references (in array context) that contains information about each of the header fields in the compressed data stream(s). =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 end of the compressed input stream has been reached. =head2 seek $z->seek($position, $whence); seek($z, $position, $whence); Provides a sub-set of the C functionality, with the restriction that it is only legal to seek forward in the input file/buffer. It is a fatal error to attempt to seek backward. Note that the implementation of C in this module does not provide true random access to a compressed file/buffer. It works by uncompressing data from the current offset in the file/buffer until it reaches the uncompressed offset specified in the parameters to C. For very small files this may be acceptable behaviour. For large files it may cause an unacceptable delay. The C<$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 is present, and is non-zero, it will enable flushing after every write/print operation. If C<$z> is associated with a buffer, this method has no effect and always returns C. B that the special variable C<$|> B be used to set or retrieve the autoflush setting. =head2 input_line_number $z->input_line_number() $z->input_line_number(EXPR) Returns the current uncompressed line number. If C is present it has the effect of setting the line number. Note that setting the line number does not change the current position within the file/buffer being read. The contents of C<$/> are used to determine what constitutes a line terminator. =head2 fileno $z->fileno() fileno($z) If the C<$z> object is associated with a file or a filehandle, C will return the underlying file descriptor. Once the C method is called C will return C. If the C<$z> object is associated with a buffer, this method will return C. =head2 close $z->close() ; close $z ; Closes the output file/buffer. For most versions of Perl this method will be automatically invoked if the IO::Uncompress::Bunzip2 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 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 explicitly and not rely on automatic closing. Returns true on success, otherwise 0. If the C option has been enabled when the IO::Uncompress::Bunzip2 object was created, and the object is associated with a file, the underlying file will also be closed. =head2 nextStream Usage is my $status = $z->nextStream(); Skips to the next compressed data stream in the input file/buffer. If a new compressed data stream is found, the eof marker will be cleared and C<$.> will be reset to 0. Returns 1 if a new stream was found, 0 if none was found, and -1 if an error was encountered. =head2 trailingData Usage is my $data = $z->trailingData(); Returns the data, if any, that is present immediately after the compressed data stream once uncompression is complete. It only makes sense to call this method once the end of the compressed data stream has been encountered. This option can be used when there is useful information immediately following the compressed data stream, and you don't know the length of the compressed data stream. If the input is a buffer, C will return everything from the end of the compressed data stream to the end of the buffer. If the input is a filehandle, C will return the data that is left in the filehandle input buffer once the end of the compressed data stream has been reached. You can then use the filehandle to read the rest of the input file. Don't bother using C if the input is a filename. If you know the length of the compressed data stream before you start uncompressing, you can avoid having to use C by setting the C option in the constructor. =head1 Importing No symbolic constants are required by IO::Uncompress::Bunzip2 at present. =over 5 =item :all Imports C and C<$Bunzip2Error>. Same as doing this use IO::Uncompress::Bunzip2 qw(bunzip2 $Bunzip2Error) ; =back =head1 EXAMPLES =head2 Working with Net::FTP See L =head1 SUPPORT General feedback/questions/bug reports should be sent to L (preferred) or L. =head1 SEE ALSO L, L, L, L, L, L, L, L, L, L, L, L, L, L, L, L, L, L, L, L, L, L L L, L, L, L The primary site for the bzip2 program is L. See the module L =head1 AUTHOR This module was written by Paul Marquess, C. =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.