--- name: "Debian::Package::List" section: "3pm" platform: "linux" package: "pkg-order" version: "1.12" release: "Debian 2.2 (Potato)" platforms: ["linux"] url: "https://new.carta.tech/Debian::Package::List" --- # Debian::Package::List(3pm) ``` Debian::Package::List - List of packages. ``` ``` use Debian::Package::List; ``` This module implements lists of packages. There is the base class Debian::Package::List, and two derived classes, namely Debian::Package::Installed and Debian::Package::New, corresponding to the installed and new packages. This is the base class that implements lists of Packages. This provides two virtual methods **check** and **extra** to be nstantiated in the derived classes.\ **new** This is the constructor for the package. This takes a named parameter, filename, which should be the path of a Packages file to use as the data for the list. This is optional. Also, an optional parameter 'Ignored Headers' shall prevent recording those Headers (useful to reduce memory usage by not recording descriptions). The argument of Ignored headers is parsed to not ignore headers we consider vital, like *Package Status Version Provides Pre-Depends Conflicts Depends* *Recommends Suggests* \ **check and extra** These are virtual functions to be instantiated in the derived classes. They are no-ops in the base class.\ **initialize** Internally, new uses the method **initialize**. This routine opens the file passed in as a named parameter filename, reads it in paragraph mode (split on empty lines), and creates a package object with each chunk. \ **add\_ignored\_headers** This routine adds to the current set of headers which are ignored if they appear in the Package file. Certain headers can not be ignored, currently *Package Status Version Provides Pre-Depends Conflicts Depends* *Recommends Suggests*. It takes in a required named parameter, *Ignored Headers*, which is a space separated list of headers to be ignored. \ **delete\_ignored\_headers** This routine deletes from the current set of headers which are ignored if they appear in the Package file. It takes in a required named parameter, *Remove Headers*, which is a space separated list of headers to be removed from the list. \ **show\_ignored\_headers** This routine shows the current set of headers which are ignored if they appear in the Package file.\ **set\_compare\_method** This method sets the routine which is used for comparing versions. Using 'undef' as parameter selects the default method, which uses dpkg --compare-versions.\ **compare\_versions** This is the generic function for comparing version numbers. It takes three arguments, one version number, a relation, and another version number. Relation can be what dpkg would accept as relations (i.e., \<, \<\<, \<=, =, \>=, \>\>, and \>). The result is a boolean value.\ **dpkg\_compare\_method** This is the default method for comparing versions. It simply calls dpkg --compare-versions, which is the right thing to do in most cases. It just does not work on non-Debian systems, so it has to be replaced (with set\_compare\_method) for this case. \=cut sub dpkg\_compare\_method {\ *my*($vers1, `$rel`, `$vers2`) = `@_`;\ my `$rv`; ``` $rv = system 'dpkg', '--compare-versions', $vers1, $rel, $vers2; # need to invert exit status returned by system return !$rv if $rv == 0 ⎪⎪ $rv == 1<<8; croak( "Bad exit status $rv from dpkg --compare-versions"); } ``` **set\_break\_on\_types** This routine adds to the current set of **Type**s which, if they appear as targets, force installation to break at that point into a separate run. It takes one required named argument, *Type List*.\ **insert\_breaks** This routine takes a ordered list of package names, and inserts breaks into the list for the types specified by the internal variable array ' \_Separate Runs'. It takes one required named argument, 'Ordered List'.\ **add** Internally, **initialize**uses the method **add**. This routine creates a package object with the required named argument 'Package\_desc'. Next, the package object is passed to virtual method **check**, and, if it passes, it is added to this instance of the list, and also adds in any symbols *provided* as virtual packages present. It is then passed to the virtual method **extra** for any extra processing of the package object.\ **delete** This routine take a required named argument Name and deletes a package with that name from the list if it exists. It also take care of erasing the package from the provides list, if indeed this package provided a virtual package.\ **mark** This routine takes two required parameters, **Package**, and **Mark** and marks **Package** with **Mark**. This is usually used to mark packages in some fashion so they will not satisfy dependencies (for packages in the installed list marked for removal, for example)\ **unmark** This routine takes two required parameters, **Package**, and **Mark** and removes **Mark** from **Package**. \ **test\_mark** This routine takes two required parameters, **Package**, and **Mark** and tests to see if the **Package** is marked with **Mark**.\ **show\_mark** This routine takes one required parameter, **Package**, and shows all marks on it.\ **list\_marks** This routine collects information in a package list about all packages with a mark on it. It returns a hash keyed on package names.\ **print** This routine loops through the packages in the list, calling the print function of each package object. It then runs through the list of provided packages, printing the name of each package provided.\ **print\_name** This routine loops through the packages in the list, printing the name. It then runs through the list of providedpackages, printing the name of each package provided.\ **names\_as\_string** This routine loops through the packages in the list and returns the names of all packages as a string.\ **init\_depends** As an extra processing of every package, the method **extra** creates a dependeny list object for the fields Depends, Pre-Depends, Recommends, Suggests, Conflicts, and Replaces. (Stored in internal fields whose names start with a blank followed by an underscore " \_")\ **get\_dependency\_information** This method **extra** creates a dependeny list object for the fields Depends, Pre-Depends, Recommends, Suggests, Conflicts, and Replaces. (Stored in internal fields whose names start with a blank followed by an underscore " \_")\ **check\_relations** This routine performs the dependency checks for the new packages. For each package in the list it calls the corresponding function in the package, and stores the results in an associative array (keyed on package name). It takes a required named argument Field, whose value should be one of Pre-Depends, Depends, Recommends, Suggests, Conflicts, or Replaces. It takes optional named arguments Consistent, (true if inconsistency in the new list should cause a warning), Installed, (a package list of installed packages), and *Warn*, which just sends a warning, and does not exclude a Package.\ **order** This routine takes one named argument **Field**, which contains the name of the package field to generate ordering information about (usually one of *Pre-Depends Depends Recommends Suggests*) and appends the ordering information so obtained to the package. This method is typically called multiple times with different arguments. The method **order\_string** below can be used to retrieve the accumulated information.\ **order\_string** This routine takes the ordering information accumulated in a package list and returns it as a string.\ **get\_ordering** This routine gathers ordering information from the packages in the list, and runs tsort on the gathered data, and returns the output of tsort.\ **set\_fatal\_failure\_on\_types** This routine adds to the current set of *Show stopper* **Type**s, taking one required named argument, *Type List*.\ **print\_result** This routine prints out the current set of dependency failures for this package list. It takes 2 named arguments, both required: **Type**, one of *Conflicts Pre-Depends Depends Recommends Suggests* **Category**, one of *Failed Found Warn Conflict* (**note**, no trailing s). Also, there are two special **Type**a, *All Critical*, which print **All** and **Show Stoppers** types respectively. \ **result\_as\_string** This routine returns the current set of dependency failures for this package list as a string. It takes 2 named arguments, both required: **Type**, one of *Conflicts Pre-Depends Depends Recommends Suggests* **Category**, one of *Failed Found Warn Conflict* (**note**, no trailing s). Also, there are two special **Type**a, *All Critical*, which print **All** and **Show Stoppers** types respectively. \ **check\_result** This routine returns the number of the current set of dependency failures for this package list. It takes 2 named arguments, both required: **Type**, one of *Conflicts Pre-Depends Depends Recommends Suggests* **Category**, one of *Failed Found Warn Conflict* (**note**, no trailing s). Also, there are two special **Type**a, *All Critical*, which print **All** and **Show Stoppers** types respectively. \ **reset\_result** This routine recalculates the results field for all the packages in the list.\ **non\_target\_as\_string** This routine returns the current set packages in this package list which are not targets of the dependency checks run on this list. One may select which of the results are reported, by selecting the **Type**, but, the result will be nothing unless the corresponding *check\_relations* has been run.\ **target\_as\_string** This routine returns the current set packages in this package list which are targets of the dependency checks run on this list. One may select which of the results are reported, by selecting the **Type**, but, the result will be nothing unless the corresponding *check\_relations* has been run.\ **test** This routine exercises the list class, initializing it with /var/lib/dpkg/status, .and then printing the names of all packages known. This is also a virtual function, in the sense that each derived class should provide an implementation. This module is a derived class of the Debian::Package::List class. This overrides the constructor new, the test function, and provides an instantiation of the virtual function **check**.\ **new** The constructor is over ridden to not require the named filename parameter, instead we use the constant /var/lib/dpkg/status as a default (the provided filename is still used if it exists).\ **check** The virtual function check is instantiated, and ensures that the package is in an ok installed status before it is included in the package list.\ **test** This routine exercises the installed list class, initializing it, and then printing the names of all packages installed. This module is a derived class of the Debian::Package::List class. This provides an instantiation of the virtual function **extra**, and also the test method. \ **extra** As an extra processing of every package, the method **extra** creates a dependeny list object for the fields Depends, Pre-Depends, Recommends, Suggests, Conflicts, and Replaces. (Stored in internal fields whose names start with a blank followed by an underscore " \_")\ **test** This routine exercises the new list class, initializing it with a file named Packages, and then printing the names of all packages therein. ``` use Debian::Package::List::Targets; ``` This module is used internally to hold reverse information about dependency (or conflict) hits..\ **new** This is the constructor for the package. It takes one named required argument, 'Package List', which is a pointer to the containing package list.\ **set\_break\_on\_types** This routine adds to the current set of **Type**s which, if they appear as targets, force installation to break at that point into a separate run. It takes one required named argument, *Type List*.\ **insert\_breaks** This routine takes a ordered list of package names, and inserts breaks into the list for the types specified by the internal variable array ' \_Separate Runs'. It takes one required named argument, 'Ordered List'.\ **add** This routine adds to the current set of dependency targets for this package. It takes 3 named arguments, all of them required: **Type**, one of *Conflicts Pre-Depends Depends Recommends Suggests* **Target**, and **Dependant**.\ **remove** This routine deletes a target from the current set of dependency targets for this package list. It takes 2 named arguments, both required: **Type**, one of *Conflicts Pre-Depends Depends Recommends* *Suggests* and **Target**.\ **is\_target** This routine . It takes 2 named arguments, both required: **Type**, one of *Conflicts Pre-Depends Depends Recommends Suggests* and **Target**. There is an undocumented **Type** *All*, which cycles over it all.\ **print\_target** This routine prints out the current set of dependency targets for this package list. It takes one required named argument: **Type**, one of *Conflicts Pre-Depends Depends Recommends Suggests* Also, there is a special **Type**, *All*, which prints **All** types. Actually, this procedure merely handles the Special types, and passes the work to the next routine.\ **do\_print** This routine prints out the current set of dependency targets for this package. It takes one required named argument: **Type**, one of *Conflicts Pre-Depends Depends Recommends Suggests* This is very inchoate, at the moment, and needs testing. None Known so far. Manoj Srivastava \