NAME

       Alien::Package - an object that represents a package

DESCRIPTION

       This is a perl object class that represents a package in an internal format usable by alien. The package
       may be a deb, a rpm, a tgz, or a slp package, etc. Objects in this class hold various fields of metadata
       from the actual packages they represent, as well as some fields pointing to the actual contents of the
       package. They can also examine an actual package on disk, and populate those fields. And they can build
       the actual package using the data stored in the fields.

       A typical use of this object class will be to instantiate an object from a class derived from this one,
       such as Alien::Package::Rpm. Feed the object a rpm file, thus populating all of its fields. Then rebless
       the object into the destination class, such as Alien::Package::Deb. Finally, ask the object to build a
       package, and the package has been converted.

FIELDS

       These fields are of course really just methods that all act similarly; allowing a value to be passed in
       to set them, or simply returning the value of the field if nothing is passed in. Child classes may
       override these fields to process input data, or to format output data. The general rule is that input
       data is modified to get things into a package-independant form, which is how the data is stored in the
       fields. When the value of a field is read, it too may be modified before it is returned, to change things
       into a form more suitable for the particular type of package.

       name
           The package's name.

       version
           The package's upstream version.

       release
           The package's distribution specific release number.

       arch
           The package's architecture, in the format used by Debian.

       maintainer
           The package's maintainer.

       depends
           The package's dependencies. Only dependencies that should exist on all target distributions can be
           put in here though (ie: lsb).

       group
           The section the package is in.

       summary
           A one line description of the package.

       description
           A longer description of the package. May contain multiple paragraphs.

       copyright
           A short statement of copyright.

       origformat
           What format the package was originally in.

       distribution
           What distribution family the package originated from.

       binary_info
           Whatever the package's package tool says when told to display info about the package.

       conffiles
           A reference to a list of all the conffiles in the package.

       files
           A reference to a list of all the files in the package.

       changelogtext
           The text of the changelog

       postinst
           The postinst script of the package.

       postrm
           The postrm script of the package.

       preinst
           The preinst script of the package.

       prerm
           The prerm script of the package.

       usescripts
           Only use the above scripts fields when generating the package if this is set to a true value.

       unpacked_tree
           Points to a directory where the package has been unpacked.

       owninfo
           If set this will be a reference to a hash, with filename as key, that holds ownership/group
           information for files that cannot be represented on the filesystem. Typically that is because the
           owners or groups just don't exist yet. It will be set at unpack time.

       modeinfo
           If set this will be a reference to a hash, with filename as key, that holds mode information for
           setuid files that have an entry in owninfo.  It will be set at unpack time.

METHODS

       init
           This is called by new(). It's a handy place to set fields, etc, without having to write your own
           new() method.

       install
           Simply installs a package file. The filename is passed.  This has to be overridden in child classes.

       test
           Test a package file. The filename is passed, should return an array of lines of test results. Child
           classses may implement this.

       filename
           Set/get the filename of the package the object represents.

           When it is set, it performs a scan of the file, populating most other fields with data from it.

           (This is just a stub; child classes should override it to actually do something.)

       scripts
           Returns a list of all non-empty maintainer scripts in the package.

       scan
           This method scans the file associated with an object, and populates as many other fields as it can
           with data from it.

       unpack
           This method unpacks the package into a temporary directory. It sets unpacked_tree to point to that
           directory.

           (This is just a stub method that makes a directory below the current working directory, and sets
           unpacked_tree to point to it. It should be overridden by child classes to actually unpack the package
           as well.)

       prep
           This method causes the object to prepare a build tree to be used in building the object. It expects
           that the unpack method has already been called. It takes the tree generated by that method, and
           mangles it somehow, to produce a suitable build tree.

           (This is just a stub method that all child classes should override.)

       cleantree
           This method should clean the unpacked_tree of any effects the prep and build methods might have on
           it.

       revert
           This method should ensure that the object is in the same state it was in before the prep method was
           called.

       build
           This method takes a prepped build tree, and simply builds a package from it. It should put the
           package in the current directory, and should return the filename of the generated package.

           (This is just a stub method that all child classes should override.)

       incrementrelease
           This method should increment the release field of the package by the specified number.

       DESTROY
           When an object is destroyed, it cleans some stuff up. In particular, if the package was unpacked, it
           is time now to wipe out the temporary directory.

       AUTOLOAD
           Handles all fields, by creating accessor methods for them the first time they are accessed.

CLASS DATA

       $Alien::Package::verbose
           If set to a nonzero value, the shell commands that are run should be output.  If set to a value
           greater than 1, any output of the commands should also be output.

CLASS METHODS

       These methods can be called on either an object or on the class itself.

       new Returns a new object of this class. Optionally, you can pass in named parameters that specify the
           values of any fields in the class.

       checkfile
           Pass it a filename, and it will return true if it looks like the file is a package of the type
           handled by the class.

       do  Runs a shell command. Is verbose or not depending on the value of $Alien::Package::verbose. Returns
           true if the command succeeds, false on failure.

       runpipe
           This is similar to backticks, but honors $Alien::Package::verbose, logging the command run if asked
           to. The output of the command is returned.

           The first parameter controls what to do on error. If it's true then any errors from the command will
           be ignored (and $? will be set). If it's false, errors will abort alien.

AUTHOR

       Joey Hess <joey@kitenet.net>