document POOL_FLAG_ADDFILEPROVIDESFILTERED

[platform/upstream/libsolv.git] / doc / libsolv-bindings.txt

LIBSOLV-BINDINGS(3)
===================
:man manual: LIBSOLV
:man source: libsolv


NAME
----
libsolv-bindings - access libsolv from perl/python/ruby

DESCRIPTION
-----------
bla bla bla

THE POOL
--------

The pool is libsolv's central resource manager. A pool consists of Solvables,
Repositories, Dependencies, each indexed by Ids.

=== CLASS METHODS ===

        Pool *Pool()
        my $pool = solv::Pool->new();
        pool = solv.Pool()
        pool = Solv::Pool.new()

Create a new pool instance. In most cases you just need
one pool.

=== ATTRIBUTES ===

        void *appdata;                  /* read/write */
        $pool->{'appdata'}
        pool.appdata
        pool.appdata

Application specific data that may be used in any way by the code using the
pool.

        Solvable solvables[];           /* read only */
        my $solvable = $pool->{'solvables'}->[$solvid];
        solvable = pool.solvables[solvid]
        solvable = pool.solvables[solvid]

Look up a Solvable by its id.

        Repo repos[];                   /* read only */
        my $repo = $pool->{'repos'}->[$repoid];
        repo = pool.repos[repoid]
        repo = pool.repos[repoid]

Look up a Repository by its id.

        Repo *installed;                /* read/write */
        $pool->{'installed'} = $repo;
        pool.installed = repo
        pool.installed = repo

Define which repository contains all the installed packages.

=== CONSTANTS ===

*POOL_FLAG_PROMOTEEPOCH*::
  Promote the epoch of the providing dependency to the requesting
  dependency if it does not contain an epoch. Used at some time
  in old rpm versions, modern systems should never need this.

*POOL_FLAG_FORBIDSELFCONFLICTS*::
  Disallow the installation of packages that conflict with themselfs.
  Debian always allowd self-conflicting packages, rpm used to forbid
  them but switched to also allowing them recently.

*POOL_FLAG_OBSOLETEUSESPROVIDES*::
  Make obsolete type dependency match against provides instead of
  just the name and version of packages. Very old versions of rpm
  used the name/version, then it got switched to provides and later
  switched back again to just name/version.

*POOL_FLAG_IMPLICITOBSOLETEUSESPROVIDES*::
  An implicit obsoletes is the internal mechanism to remove the
  old package on an update. The default is to remove all packages
  with the same name, rpm-5 switched to also removing packages
  providing the same name.

*POOL_FLAG_OBSOLETEUSESCOLORS*::
  Rpm's multilib implementation (used in RedHat and Fedora)
  distinguishes between 32bit and 64bit packages (the terminology
  is that they have a different color). If obsolteusescolors is
  set, packages with different colors will not obsolete each other.
  This is also true for implicit obsoletes, thus you can install
  both the 32bit and the 64bit version of a package with the
  same name.

*POOL_FLAG_NOINSTALLEDOBSOLETES*::
  New versions of rpm consider the obsoletes of installed packages
  when checking for dependency, thus you may not install a package
  that is obsoleted by some other installed package, unless you
  also deinstall the other package.

*POOL_FLAG_HAVEDISTEPOCH*::
  Mandriva added a new field called distepoch that gets checked in
  version comparison if the epoch/version/release of two packages
  are the same.

*POOL_FLAG_NOOBSOLETESMULTIVERSION*::
  If a package is installed in multiversionmode, rpm used to ignore
  both the implicit obsoletes and the obsolete dependency of a
  package. This was changed to ignoring just the implicit obsoletes,
  thus you may install multiple versions of the same name, but
  obsoleted packages still get removed.

*POOL_FLAG_ADDFILEPROVIDESFILTERED*::
  Make the addfileprovides method only add files from the standard
  locations (i.e. the ``bin'' and ``etc'' directories). This is
  useful if you have only few packages that use non-standard file
  dependencies, but you still wand the fast speed that addfileprovides()
  generates.

=== METHODS ===

        void free()
        $pool->free();
        pool.free()
        pool.free()

Free a pool. This is currently done with a method instead of relying on
reference counting or garbage collection because it's hard to track every
reference to a pool.

        void setdebuglevel(int level)
        $pool->setdebuglevel($level);
        pool.setdebuglevel(level)
        pool.setdebuglevel(level)

Set the debug level. A value of zero means no debug output, the higher the
value, the more output is generated.

        int set_flag(int flag, int value)
        my $oldvalue = $pool->set_flag($flag, $value);
        oldvalue = pool.set_flag(flag, value)
        oldvalue = pool.set_flag(flag, value)

        int get_flag(int flag)
        my $value = $pool->get_flag($flag);
        value = pool.get_flag(flag)
        value = pool.get_flag(flag)

Set/get a pool specific flag. The flags define how the system works, e.g. how
the package manager treats obsoletes. The default flags should be sane for most
applications, but in some cases you may want to tweak a flag, for example if
you want to solv package dependencies for some other system than yours.

        void set_rootdir(const char *rootdir)
        $pool->set_rootdir(rootdir);
        pool.set_rootdir(rootdir)
        pool.set_rootdir(rootdir)

        const char *get_rootdir()
        my $rootdir = $pool->get_rootdir();
        rootdir = pool.get_rootdir()
        rootdir = pool.get_rootdir()

Set/get the rootdir to use. This is useful if you want package management
to work only in some directory, for example if you want to setup a chroot
jail. Note that the rootdir will only be prepended to file paths if the
*REPO_USE_ROOTDIR* flag is used.

        void setarch(const char *arch = 0)
        $pool->setarch();
        pool.setarch()
        pool.setarch()

Set the architecture for your system. The architecture is used to determine
which packages are installable. It defaults to the result of ``uname -m''.

        Repo *add_repo(const char *name)
        $repo = $pool->add_repo($name);
        repo = pool.add_repo(name)
        repo = pool.add_repo(name)

Add a Repository with the specified name to the pool. The reposiory is empty
on creation, use the repository methods to populate it with packages.

        Repoiterator *repos_iter()
        for my $repo (@{$pool->repos_iter()})
        for repo in pool.repos_iter():
        for repo in pool.repos_iter()

Iterate over the existing repositories.

        Solvableiterator *solvables_iter()
        for my $solvable (@{$pool->solvables_iter()})
        for solvable in pool.solvables_iter():
        for solvable in pool.solvables_iter()

Iterate over the existing solvables.

        Dep *Dep(const char *str, bool create=1)
        my $dep = $pool->Dep($string);
        dep = pool.Dep(string)
        dep = pool.Dep(string)

Create an object describing a string or dependency. If the string is currently
not in the pool and _create_ is false, *undef*/*None*/*nil* is returned.

        void addfileprovides()
        $pool->addfileprovides();
        pool.addfileprovides()
        pool.addfileprovides()

        Queue addfileprovides_queue()
        my @ids = $pool->addfileprovides_queue();
        ids = pool.addfileprovides_queue()
        ids = pool.addfileprovides_queue()

Some package managers like rpm allow dependencies on files contained in other
packages. To allow libsolv to deal with those dependencies in an efficient way,
you need to call the addfileprovides method after creating and reading all
repositories. This method will scan all dependency for file names and than scan
all packages for matching files. If a filename has been matched, it will be
added to the provides list of the corresponding package. The
addfileprovides_queue variant works the same way but returns an array
containing all file dependencies. This information can be stored with the
repository to speed up the next usage of the repository.

        void createwhatprovides()
        $pool->createwhatprovides();
        pool.createwhatprovides()
        pool.createwhatprovides()

Create the internal ``whatprovides'' hash over all of the provides of all
packages. This method must be called before doing any lookups on provides.
It's encuraged to do it right after all repos are set up, usually right after
the call to addfileprovides().

        Queue whatprovides(DepId dep)
        my @solvables = $pool->whatprovides($dep);
        solvables = pool.whatprovides(dep)
        solvables = pool.whatprovides(dep)

Return all solvables that provide the specified dependency. You can use either
a Dep object or an simple Id as argument.

        Queue matchprovidingids(const char *match, int flags)
        my @ids = $pool->matchprovidingids($match, $flags);
        ids = pool.matchprovidingids(match, flags)
        ids = pool.matchprovidingids(match, flags)

Search the names of all provides and return the ones matching the specified
string. See the Dataiterator class for the allowed flags.

        Id towhatprovides(Queue ids)
        my $offset = $pool->towhatprovides(\@ids);
        offset = pool.towhatprovides(ids)
        offset = pool.towhatprovides(ids)

``Internalize'' an array containing Ids. The returned value can be used to
create solver jobs working on a specific set of packages. See the Solver class
for more information.

        bool isknownarch(DepId id)
        my $bool = $pool->isknownarch($id);
        bool = pool.isknownarch(id)
        bool = pool.isknownarch?(id)

Return true if the specified Id describs a known architecture.

        Solver *Solver()
        my $solver = $pool->Solver();
        solver = pool.Solver()
        solver = pool.Solver()

Create a new solver object.

        Solver *Job(int how, Id what)
        my $job = $pool->Job($how, $what);
        job = pool.Job(how, what)
        job = pool.Job(how, what)

Create a new Job object. Kind of low level, in most cases you would use a
Selection or Dep job constructor instead.

        Selection *Selection()
        my $sel = $pool->Selection();
        sel = pool.Selection()
        sel = pool.Selection()

Create an empty selection. Useful as a starting point for merging other
selections.

        Selection *Selection_all()
        my $sel = $pool->Selection_all();
        sel = pool.Selection_all()
        sel = pool.Selection_all()
        
Create a selection containing all packages. Useful as starting point for
intersecting other selections or for update/distupgrade jobs.

        Selection *select(const char *name, int flags)
        my $sel = $pool->select($name, $flags);
        sel = pool.select(name, flags)
        sel = pool.select(name, flags)

Create a selection by matching packages against the specified string. See the
Selection class for a list of flags and how to create solver jobs from a
selection.

        void setpooljobs(Jobs *jobs)
        $pool->setpooljobs(\@jobs);
        pool.setpooljobs(jobs)
        pool.setpooljobs(jobs)

        Jobs *getpooljobs()
        @jobs = $pool->getpooljobs();
        jobs = pool.getpooljobs()
        jobs = pool.getpooljobs()

Get/Set fixed jobs stored in the pool. Those jobs are automatically appended to
all solver jobs, they are meant for fixed configurations like which packages
can be multiversion installed, which packages were userinstalled or must not be
erased.

        void set_loadcallback(Callable *callback)
        $pool->setloadcallback(\&callbackfunction);
        pool.setloadcallback(callbackfunction)
        pool.setloadcallback { |repodata| ... }

Set the callback function called when repository metadata needs to be loaded on
demand. To make use of this feature, you need to create repodata stubs that
tell the library which data is available but not loaded. If later on the data
needs to be accessed, the callback function is called with a repodata argument.
You can then load the data (maybe fetching it first from an remote server).
The callback should return true if the data has been made available.

=== DATA RETRIEVAL METHODS ===

In the following functions, the _keyname_ argument describes what to retrive.
For the standard cases you can use the available Id constants. For example,

        $solv::SOLVABLE_SUMMARY
        solv.SOLVABLE_SUMMARY
        Solv::SOLVABLE_SUMMARY

selects the ``Summary'' entry of a solvable. The _solvid_ argument selects the
desired solvable by Id.

        const char *lookup_str(Id solvid, Id keyname)
        my $string = $pool->lookup_str($solvid, $keyname);
        string = pool.lookup_str(solvid, keyname)
        string = pool.lookup_str(solvid, keyname)

        Id lookup_id(Id solvid, Id keyname)
        my $id = $pool->lookup_id($solvid, $keyname);
        id = pool.lookup_id(solvid, keyname)
        id = pool.lookup_id(solvid, keyname)

        unsigned long long lookup_num(Id solvid, Id keyname, unsigned long long notfound = 0)
        my $num = $pool->lookup_num($solvid, $keyname);
        num = pool.lookup_num(solvid, keyname)
        num = pool.lookup_num(solvid, keyname)

        bool lookup_void(Id solvid, Id keyname)
        my $bool = $pool->lookup_void($solvid, $keyname);
        bool = pool.lookup_void(solvid, keyname)
        bool = pool.lookup_void(solvid, keyname)

        Queue lookup_idarray(Id solvid, Id keyname)
        my @ids = $pool->lookup_idarray($solvid, $keyname);
        ids = pool.lookup_idarray(solvid, keyname)
        ids = pool.lookup_idarray(solvid, keyname)

        Chksum *lookup_checksum(Id solvid, Id keyname)
        my $chksum = $pool->lookup_checksum($solvid, $keyname);
        chksum = pool.lookup_checksum(solvid, keyname)
        chksum = pool.lookup_checksum(solvid, keyname)

Lookup functions. Return the data element stored in the specified solvable.
You should probably use the methods of the Solvable class instead.

        Dataiterator *Dataiterator(Id solvid, Id keyname, const char *match, int flags)
        my $di = $pool->Dataiterator($solvid, $keyname, $match, $flags);
        di = pool.Dataiterator(solvid, keyname, match, flags)
        di = pool.Dataiterator(solvid, keyname, match, flags)

        for my $d (@$di)
        for d in di:
        for d in di

Iterate over the matching data elements. See the Dataiterator class for more
information.

=== ID METHODS ===

The following methods deal with Ids, i.e. integers representing objects in the
pool. They are considered ``low level'', in most cases you would not use them
but instead the object orientated methods.

        Repo *id2repo(Id id)
        $repo = $pool->id2repo($id);
        repo = pool.id2repo(id)
        repo = pool.id2repo(id)

Lookup an existing Repository by id. You can also do this by using the *repos*
attribute.

        Solvable *id2solvable(Id id)
        $solvable = $pool->id2solvable($id);
        solvable = pool.id2solvable(id)
        solvable = pool.id2solvable(id)

Lookup an existing Repository by id. You can also do this by using the
*solvables* attribute.

        const char *solvid2str(Id id)
        my $str = $pool->solvid2str($id);
        str = pool.solvid2str(id)
        str = pool.solvid2str(id)

Return a string describing the Solvable with the specified id. The string
consists of the name, version, and architecture of the Solvable.

        Id str2id(const char *str, bool create=1)
        my $id = pool->str2id($string);
        id = pool.str2id(string)
        id = pool.str2id(string)

        const char *id2str(Id id)
        $string = pool->id2str($id);
        string = pool.id2str(id)
        string = pool.id2str(id)

Convert a string into an Id and back. If the string is currently not in the
pool and _create_ is false, zero is returned.

        Id rel2id(Id name, Id evr, int flags, bool create=1)
        my $id = pool->rel2id($nameid, $evrid, $flags);
        id = pool.rel2id(nameid, evrid, flags)
        id = pool.rel2id(nameid, evrid, flags)

Create a ``relational'' dependency. Such dependencies consist of a name part,
the _flags_ describing the relation, and a version part. The flags are:

        $solv::REL_EQ | $solv::REL_GT | $solv::REL_LT
        solv.REL_EQ | solv.REL_GT | solv.REL_LT
        Solv::REL_EQ | Solv::REL_GT | Solv::REL_LT

Thus, if you want a ``\<='' relation, you would use *REL_LT | REL_EQ*.

        Id id2langid(Id id, const char *lang, bool create=1)
        my $id = $pool->id2langid($id, $language);
        id = pool.id2langid(id, language)
        id = pool.id2langid(id, language)

Create a language specific Id from some other id. This function simply converts
the id into a string, appends a dot and the specified language to the string
and converts the result back into an Id.

        const char *dep2str(Id id)
        $string = pool->dep2str($id);
        string = pool.dep2str(id)
        string = pool.dep2str(id)

Convert a dependency id into a string. If the id is just a string, this
function has the same effect as id2str(). For relational dependencies, the
result is the correct ``name relation evr'' string.


THE DEPENDENCY CLASS
--------------------
The dependency class is an object orientated way to work with strings and
dependencies. Internally, dependencies are represented as Ids, i.e. simple
numbers. Dependency objects can be constructed by using the Pool's Dep()
method.

=== ATTRIBUTES ===

        Pool *pool;             /* read only */
        $dep->{'pool'}
        dep.pool
        dep.pool

Back reference to the pool this dependency belongs to.

        Id id;          /* read only */
        $dep->{'id'}
        dep.id
        dep.id

The id of this dependency.

== Methods ==

        Dep *Rel(int flags, DepId evrid, bool create=1)
        my $reldep = $dep->Rel($flags, $evrdep);
        reldep = dep.Rel(flags, evrdep)
        reldep = dep.Rel(flags, evrdep)

Create a relational dependency from to string dependencies and a flags
argument. See the pool's rel2id method for a description of the flags.

        Selection *Selection_name(int setflags = 0)
        my $sel = $dep->Selection_name();
        sel = dep.Selection_name()
        sel = dep.Selection_name()

Create a Selection from a dependency. The selection consists of all packages
that have a name equal to the dependency. If the dependency is of a relational
type, the packages version must also fulfill the dependency.

        Selection *Selection_provides(int setflags = 0)
        my $sel = $dep->Selection_provides();
        sel = dep.Selection_provides()
        sel = dep.Selection_provides()

Create a Selection from a dependency. The selection consists of all packages
that have at least one provides matching the dependency.

        const char *str()
        my $str = $dep->str();
        str = $dep.str()
        str = $dep.str()

Return a string describing the dependency.

        <stringification>
        my $str = "$dep";
        str = str(dep)
        str = dep.to_s

Same as calling the str() method.

        <equality>
        if ($dep1 == $dep2)
        if dep1 == dep2:
        if dep1 == dep2

The dependencies are equal if they are part of the same pool and have the same
ids.

THE REPOSITORY CLASS
--------------------
A Repository describes a group of packages, normally comming from the same
source. Repositories are created by the Pool's add_repo() method.

=== ATTRIBUTES ===

        Pool *pool;                     /* read only */
        $repo->{'pool'}
        repo.pool
        repo.pool

Back reference to the pool this dependency belongs to.

        Id id;                          /* read only */
        $repo->{'id'}
        repo.id
        repo.id

The id of the repository.

        const char *name;               /* read/write */
        $repo->{'name'}
        repo.name
        repo.name
        
The repositories name. To libsolv, the name is just a string with no specific
meaning.

        int prioprity;                  /* read/write */
        $repo->{'priority'}
        repo.priority
        repo.priority

The priority of the repository. A higher number means that packages of this
repository will be chosen over other repositories, even if they have a greater
package version.

        int subprioprity;               /* read/write */
        $repo->{'subpriority'}
        repo.subpriority
        repo.subpriority

The sub-priority of the repository. This value is compared when the priorities
of two repositories are the same. It is useful to make the library prefer
on-disk repositories to remote ones.

        int nsolvables;                 /* read only */
        $repo->{'nsolvables'}
        repo.nsolvables
        repo.nsolvables

The number of solvables in this repository.

        void *appdata;                  /* read/write */
        $repo->{'appdata'}
        repo.appdata
        repo.appdata

Application specific data that may be used in any way by the code using the
repository.

        Datapos *meta;                  /* read only */
        $repo->{'meta'}
        repo.meta
        repo.meta

Return a Datapos object of the repodata's metadata. You can use the lookup
methods of the Datapos class to lookup metadata attributes, like the repository
timestamp.

=== CONSTANTS ===

*REPO_REUSE_REPODATA*::
  Reuse the last repository data aera (``repodata'') instead of creating a new
  one.

*REPO_NO_INTERNALIZE*::
  Do not internalize the added repository data. This is useful if
  you plan to add more data because internalization is a costly
  operation.

*REPO_LOCALPOOL*::
  Use the repodata's pool for Id storage instead of the global pool. Useful
  if you don't want to pollute the global pool with many unneeded ids, like
  when storing the filelist.

*REPO_USE_LOADING*::
  Use the repodata that is currently being loaded instead of creating a new one.
  This only makes sense if used in a load callback.

*REPO_EXTEND_SOLVABLES*::
  Do not create new solvables for the new data, but match existing solvables and
  add the data to them. Repository metadata is often split into multiple parts,
  with one primary file describing all packages and other parts holding
  information that is normally not needed, like the changelog.

*REPO_USE_ROOTDIR*::
  Prepend the pool's rootdir to the path when doing file operations.

*REPO_NO_LOCATION*::
  Do not add a location element to the solvables. Useful if the solvables are
  not in the final position, so you can add the correct location later in your code.

*SOLV_ADD_NO_STUBS*::
  Do not create stubs for repository parts that can be downloaded on demand.

*SUSETAGS_RECORD_SHARES*::
  This is specific to the add_susetags() method. Susetags allows to refer to already
  read packages to save disk space. If this data sharing needs to work over multiple
  calls to add_susetags, you need to specify this flag so that the share information
  is made available to subsequent calls.

=== METHODS ===

        void free(bool reuseids = 0)
        $repo->free();
        repo.free()
        repo.free()

Free the repository and all solvables it contains. If _reuseids_ is set to
true, the solvable ids and the repository id may be reused by the library when
added new solvables. Thus you should leave it false if you are not sure that
somebody holds a reference.

        void empty(bool reuseids = 0)
        $repo->empty();
        repo.empty()
        repo.empty()

Free all the solvables in a repository. The repository will be empty after this
call. See the free() method for the meaning of _reuseids_.

        bool isempty()
        $repo->isempty()
        repo.empty()
        repo.empty?

Return true if there are no solvables in this repository.

        void internalize()
        $repo->internalize();
        repo.internalize()
        repo.internalize()

Internalize added data. Data must be internalized before it is available to the
lookup and data iterator functions.

        bool write(FILE *fp)
        $repo->write($fp)
        repo.write(fp)
        repo.write(fp)

Write a repo as a ``solv'' file. These files can be read very fast and thus are
a good way to cache repository data. Returns false if there was some error
writing the file.

        Solvableiterator *solvables_iter()
        for my $solvable (@{$repo->solvables_iter()})
        for solvable in repo.solvables_iter():
        for solvable in repo.solvables_iter()

Iterate over all solvables in a repository.

        Repodata *add_repodata(int flags = 0)
        my $repodata = $repo->add_repodata();
        repodata = repo.add_repodata()
        repodata = repo.add_repodata()

Add a new repodata area to the repository. This is normally automatically
done by the repo_add methods, so you need this method only in very
rare circumstances.

        void create_stubs()
        $repo->create_stubs();
        repo.create_stubs()
        repo.create_stubs()

Calls the create_stubs() repodata method for the last repodata of the
repository.

        bool iscontiguous()
        $repo->iscontiguous()
        repo.iscontiguous()
        repo.iscontiguous?

Return true if the solvables of this repository are all in a single block with
no holes, i.e. they have consecutive ids.

        Repodata *first_repodata()
        my $repodata = $repo->first_repodata();
        repodata = repo.first_repodata()
        repodata = repo.first_repodata()

Checks if all repodatas but the first repodata are extensions, and return the
first repodata if this is the case. Useful if you want to do a store/retrive
sequence on the repository to reduce the memory using and enable paging, as
this does not work if the rpository contains multiple non-extension repodata
areas.

        Selection *Selection(int setflags = 0)
        my $sel = $repo->Selection();
        sel = repo.Selection()
        sel = repo.Selection()

Create a Selection consisting of all packages in the repository.

        Dataiterator *Dataiterator(Id p, Id key, const char *match, int flags)
        my $di = $repo->Dataiterator($solvid, $keyname, $match, $flags);
        di = repo.Dataiterator(solvid, keyname, match, flags)
        di = repo.Dataiterator(solvid, keyname, match, flags)

        for my $d (@$di)
        for d in di:
        for d in di

Iterate over the matching data elements in this repository. See the
Dataiterator class for more information.

        <stringification>
        my $str = "$repo";
        str = str(repo)
        str = repo.to_s

Return the name of the repository, or "Repo#<id>" if no name is set.

        <equality>
        if ($repo1 == $repo2)
        if repo1 == repo2:
        if repo1 == repo2

Two repositories are equal if they belong to the same pool and have the same id.

=== DATA ADD METHODS ===

        Solvable *add_solvable()
        $repo->add_solvable();
        repo.add_solvable()
        repo.add_solvable()

Add a single empty solvable to the repository. Returns a Solvable object, see
the Solvable class for more information.

        bool add_solv(const char *name, int flags = 0)
        $repo->add_solv($name, $flags);
        repo.add_solv(name, flags)
        repo.add_solv(name, flags)

        bool add_solv(FILE *fp, int flags = 0)
        $repo->add_solv($fp, $flags);
        repo.add_solv(fp, flags)
        repo.add_solv(fp, flags)

Read a ``solv'' file and add its contents to the repository. These files can be
written with the write() method and are normally used as fast cache for
repository metadata.

        bool add_rpmdb(int flags = 0)
        $repo->add_rpmdb($flags);
        repo.add_rpmdb(flags)
        repo.add_rpmdb(flags)

        bool add_rpmdb_reffp(FILE *reffp, int flags = 0)
        $repo->add_rpmdb_reffp($reffp, $flags);
        repo.add_rpmdb_reffp($reffp, flags)
        repo.add_rpmdb_reffp($reffp, flags)

Add the contents of the rpm database to the repository. If a solv file
containing an old version of the database is available, it can be passed as
reffp to speed up reading.

        bool add_rpm(const char *name, int flags = 0)
        $repo->add_rpm($name, $flags);
        repo.add_rpm(name, flags)
        repo.add_rpm(name, flags)

Add the metadata of a single rpm package to the repository.

        bool add_rpmdb_pubkeys(int flags = 0)
        $repo->add_rpmdb_pubkeys();
        repo.add_rpmdb_pubkeys()
        repo.add_rpmdb_pubkeys()

Add all pubkeys contained in the rpm database to the repository. Note that
newer rpm versions also allow to store the pubkeys in some directory instead
of the rpm database.

        bool add_pubkey(const char *keyfile, int flags = 0)
        $repo->add_pubkey($keyfile);
        repo.add_pubkey($keyfile)
        repo.add_pubkey($keyfile)

Add a pubkey from a file to the repository.

        bool add_rpmmd(FILE *fp, const char *language, int flags = 0)
        $repo->add_rpmmd($fp, $language);
        repo.add_rpmmd(fp, language)
        repo.add_rpmmd(fp, language)

Add metadata stored in the "rpm-md" format (i.e. from files in the ``repodata''
directory) to a repository. Supported files are "primary", "filelists",
"other", "suseinfo". Do not forget to specify the *REPO_EXTEND_SOLVABLES* for
extension files like "filelists" and "other". Use the _language_ parameter if
you have language extension files, otherwise simply use a *undef*/*None*/*nil*
parameter.

        bool add_repomdxml(FILE *fp, int flags = 0)
        $repo->add_repomdxml($fp);
        repo.add_repomdxml(fp)
        repo.add_repomdxml(fp)

Add the repomd.xml meta description from the "rpm-md" format to the repository.
This file contains information about the repository like keywords, and also a
list of all database files with checksums. The data is added the the "meta"
section of the repository, i.e. no package gets created.

        bool add_updateinfoxml(FILE *fp, int flags = 0)
        $repo->add_updateinfoxml($fp);
        repo.add_updateinfoxml(fp)
        repo.add_updateinfoxml(fp)

Add the updateinfo.xml file containing available maintenance updates to the
repository. All updates are created as special packages that have a "patch:"
prefix in their name.

        bool add_deltainfoxml(FILE *fp, int flags = 0)
        $repo->add_deltainfoxml($fp);
        repo.add_deltainfoxml(fp)
        repo.add_deltainfoxml(fp)

Add the deltainfo.xml file (also called prestodelta.xml) containing available
delta-rpms to the repository. The data is added to the "meta" section, i.e. no
package gets created.

        bool add_debdb(int flags = 0)
        $repo->add_debdb();
        repo.add_debdb()
        repo.add_debdb()

Add the contents of the debian installed package database to the repository.

        bool add_debpackages(FILE *fp, int flags = 0)
        $repo->add_debpackages($fp);
        repo.add_debpackages($fp)
        repo.add_debpackages($fp)

Add the contents of the debian repository metadata (the "packages" file)
to the repository.

        bool add_deb(const char *filename, int flags = 0)
        $repo->add_deb($filename);
        repo.add_deb(filename)
        repo.add_deb(filename)

Add the metadata of a single deb package to the repository.

        bool add_mdk(FILE *fp, int flags = 0)
        $repo->add_mdk($fp);
        repo.add_mdk($fp)
        repo.add_mdk($fp)

Add the contents of the mageia/mandriva repository metadata (the
"synthesis.hdlist" file) to the repository.

        bool add_mdk_info(FILE *fp, int flags = 0)
        $repo->add_mdk($fp);
        repo.add_mdk($fp)
        repo.add_mdk($fp)

Extend the packages from the synthesis file with the info.xml and files.xml
data. Do not forget to specify *REPO_EXTEND_SOLVABLES*.

        bool add_arch_repo(FILE *fp, int flags = 0)
        $repo->add_arch_repo($fp);
        repo.add_arch_repo($fp)
        repo.add_arch_repo($fp)

Add the contents of the archlinux repository metadata (the ".db.tar" file) to
the repository.

        bool add_arch_local(const char *dir, int flags = 0)
        $repo->add_arch_local($dir);
        repo.add_arch_local($dir)
        repo.add_arch_local($dir)

Add the contents of the archlinux installed package database to the repository.
The _dir_ parameter is usually set to "/var/lib/pacman/local".

        bool add_content(FILE *fp, int flags = 0)
        $repo->add_content($fp);
        repo.add_content(fp)
        repo.add_content(fp)

Add the ``content'' meta description from the susetags format to the repository.
This file contains information about the repository like keywords, and also
a list of all database files with checksums. The data is added the the "meta"
section of the repository, i.e. no package gets created.

        bool add_susetags(FILE *fp, Id defvendor, const char *language, int flags = 0)
        $repo->add_susetags($fp, $defvendor, $language);
        repo.add_susetags(fp, defvendor, language)
        repo.add_susetags(fp, defvendor, language)

Add repository metadata in the susetags format to the repository. Like with
add_rpmmd, you can specify a language if you have language extension files. The
_defvendor_ parameter provides a default vendor for packages with missing
vendors, it is usually provided in the content file.

        bool add_products(const char *dir, int flags = 0)
        $repo->add_products($dir);
        repo.add_products(dir)
        repo.add_products(dir)

Add the installed SUSE products database to the repository. The _dir_ parameter
is usually "/etc/products.d".


THE SOLVABLE CLASS
------------------
A solvable describes all the information of one package. Each solvable belongs to
one repository, it can be added and filled manually but in most cases solvables
will get created by the repo_add methods.

=== ATTRIBUTES ===

        Repo *repo;                     /* read only */
        $solvable->{'repo'}
        solvable.repo
        solvable.repo

The repository this solvable belongs to.

        Pool *pool;                     /* read only */
        $solvable->{'pool'}
        solvable.pool
        solvable.pool

The pool this solvable belongs to, same as the pool of the repo.

        Id id;                          /* read only */
        $solvable->{'id'}
        solvable.id
        solvable.id

The specific id of the solvable.

        char *name;                     /* read/write */
        $solvable->{'name'}
        solvable.name
        solvable.name

        char *evr;                      /* read/write */
        $solvable->{'evr'}
        solvable.evr
        solvable.evr

        char *arch;                     /* read/write */
        $solvable->{'arch'}
        solvable.arch
        solvable.arch

        char *vendor;                   /* read/write */
        $solvable->{'vendor'}
        solvable.vendor
        solvable.vendor

Easy access to often used attributes of solvables. They are
internally stored as Ids.

        Id nameid;                      /* read/write */
        $solvable->{'nameid'}
        solvable.nameid
        solvable.nameid

        Id evrid;                       /* read/write */
        $solvable->{'evrid'}
        solvable.evrid
        solvable.evrid

        Id archid;                      /* read/write */
        $solvable->{'archid'}
        solvable.archid
        solvable.archid

        Id vendorid;                    /* read/write */
        $solvable->{'vendorid'}
        solvable.vendorid
        solvable.vendorid

Raw interface to the ids. Useful if you want to search for
a specific id and want to avoid the string compare overhead.

=== METHODS ===

        const char *lookup_str(Id keyname)
        my $string = $solvable->lookup_str($keyname);
        string = solvable.lookup_str(keyname)
        string = solvable.lookup_str(keyname)

        Id lookup_id(Id keyname)
        my $id = $solvable->lookup_id($keyname);
        id = solvable.lookup_id(solvid)
        id = solvable.lookup_id(solvid)

        unsigned long long lookup_num(Id solvid, Id keyname, unsigned long long notfound = 0)
        my $num = $solvable->lookup_num($keyname);
        num = solvable.lookup_num(keyname)
        num = solvable.lookup_num(keyname)

        bool lookup_void(Id keyname)
        my $bool = $solvable->lookup_void($keyname);
        bool = solvable.lookup_void(keyname)
        bool = solvable.lookup_void(keyname)

        Chksum *lookup_checksum(Id keyname)
        my $chksum = $solvable->lookup_checksum($keyname);
        chksum = solvable.lookup_checksum(keyname)
        chksum = solvable.lookup_checksum(keyname)

        Queue lookup_idarray(Id keyname, Id marker = -1)
        my @ids = $solvable->lookup_idarray($keyname);
        ids = solvable.lookup_idarray(keyname)
        ids = solvable.lookup_idarray(keyname)

        Queue lookup_deparray(Id keyname, Id marker = -1)
        my @deps = $solvable->lookup_deparray($keyname);
        deps = solvable.lookup_deparray(keyname)
        deps = solvable.lookup_deparray(keyname)
        
Generic lookup methods. Retrieve data stored for the specific keyname.
The lookup_idarray() method will return an array of Ids, use
lookup_deparray if you want an array of Dependency objects instead.
Some Id arrays contain two parts of data divided by a specific marker,
for example the provides array uses the SOLVABLE_FILEMARKER id to
store both the ids provided by the package and the ids added by
the addfileprovides method. The default, -1, translates to the
correct marker for the keyname and returns the first part of the
array, use 1 to select the second part or 0 to retrive all ids
including the marker.

        const char *lookup_location(unsigned int *OUTPUT);
        my ($location, $medianr) = $solvable->lookup_location();
        location, medianr = solvable.lookup_location()
        location, medianr = solvable.lookup_location()

Return a tuple containing the on-media location and an optional
media number for multi-part repositories (e.g. repositories
spawning multiple DVDs).

        void add_deparray(Id keyname, DepId dep, Id marker = -1);
        $solvable->add_deparray($keyname, $dep);
        solvable.add_deparray(keyname, dep)
        solvable.add_deparray(keyname, dep)

Add a new dependency to the attributes stored in keyname.

        bool installable();
        $solvable->installable()
        solvable.installable()
        solvable.installable?

Return true if the solvable is installable on the system. Solvables
are not installable if the system does not support their architecture.

        bool isinstalled();
        $solvable->isinstalled()
        solvable.isinstalled()
        solvable.isinstalled?

Return true if the solvable is installed on the system.

        Selection *Selection(int setflags = 0)
        my $sel = $solvable->Selection();
        sel = solvable.Selection()
        sel = solvable.Selection()

Create a Selection containing just the single solvable.

        const char *str()
        my $str = $solvable->str();
        str = $solvable.str()
        str = $solvable.str()

Return a string describing the solvable. The string consists of the name,
version, and architecture of the Solvable.

        <stringification>
        my $str = "$solvable";
        str = str(solvable)
        str = solvable.to_s

Same as calling the str() method.

        <equality>
        if ($solvable1 == $solvable2)
        if solvable1 == solvable2:
        if solvable1 == solvable2

Two solvables are equal if they are part of the same pool and have the same
ids.

THE DATAITERATOR CLASS
----------------------

Dataiterators can be used to do complex string searches or
to iterate over arrays. They can be created via the
constructors in the Pool, Repo, and Solvable classes. The
Repo and Solvable constructors will limit the search to
the repository or the specific package.

=== CONSTANTS ===

*SEARCH_STRING*::
  Return a match if the search string matches the value.

*SEARCH_STRINGSTART*::
  Return a match if the value starts with the search string.

*SEARCH_STRINGEND*::
  Return a match if the value ends with the search string.

*SEARCH_SUBSTRING*::
  Return a match if the search string can be matched somewhere
  in the value.

*SEARCH_GLOB*::
  Do a glob match of the search string against the value.

*SEARCH_REGEX*::
  Do a regular expression match of the search string against
  the value.

*SEARCH_NOCASE*::
  Ignore case when matching strings. Works for all the above
  match types.

*SEARCH_FILES*::
  Match the complete filenames of the file list, not just the
  base name.

*SEARCH_COMPLETE_FILELIST*::
  When matching the file list, check every file of the package
  not just the subset from the primary metadata.

*SEARCH_CHECKSUMS*::
  Allow the matching of checksum entries.

=== METHODS ===

        void prepend_keyname(Id keyname);
        $di->prepend_keyname($keyname);
        di.prepend_keyname(keyname)
        di.prepend_keyname(keyname)

Do a sub-search in the array stored in keyname.

        void skip_solvable();
        $di->kip_solvable();
        di.skip_solvable()
        di.skip_solvable()

Stop matching the current solvable and advance to the next
one.

        <iteration>
        for my $d (@$di)
        for d in di:
        for d in di

Iterate through the matches. If there is a match, the object
in d will be of type Datamatch.

THE DATAMATCH CLASS
-------------------
Objects of this type will be created for every value matched
by a dataiterator.

=== ATTRIBUTES ===

        Pool *pool;                             /* read only */
        $d->{'pool'}
        d.pool
        d.pool

Back pointer to pool.

        Repo *repo;                             /* read only */
        $d->{'repo'}
        d.repo
        d.repo

The repository containing the matched object.

        Solvable *solvable;                     /* read only */
        $d->{'solvable'}
        d.solvable
        d.solvable

The solvable containing the value that was matched.

        Id solvid;                              /* read only */
        $d->{'solvid'}
        d.solvid
        d.solvid

The id of the solvable that matched.

=== METHODS ===

        Id key_id();
        $d->key_id()
        d.key_id()
        d.key_id()

        const char *key_idstr();
        $d->key_idstr()
        d.key_idstr()
        d.key_idstr()

The keyname that matched, either as id or string.

        Id type_id();
        $d->type_id()
        d.type_id()
        d.type_id()

        const char *type_idstr();
        $d->type_idstr();
        d.type_idstr()
        d.type_idstr()

The key type of the value that was matched, either as id or string.

        Id id();
        $d->id()
        d.id()
        d.id()

        Id idstr();
        $d->idstr()
        d.idstr()
        d.idstr()

The Id of the value that was matched (only valid for id types),
either as id or string.

        const char *str();
        $d->str()
        d.str()
        d.str()

The string value that was matched (only valid for string types).

        unsigned long long num();
        $d->num()
        d.num()
        d.num()

The numeric value that was matched (only valid for numeric types).

        unsigned int num2();
        $d->num2()
        d.num2()
        d.num2()

The secondary numeric value that was matched (only valid for types
containing two values).

        Datapos *pos();
        my $pos = $d->pos();
        pos = d.pos()
        pos = d.pos()

The position object of the current match. It can be used to do
sub-searches starting at the match (if it is of an array type).
See the Datapos class for more information.

        Datapos *parentpos();
        my $pos = $d->parentpos();
        pos = d.parentpos()
        pos = d.parentpos()

The position object of the array containing the current match.
It can be used to do sub-searches, see the Datapos class for more
information.

        <stringification>
        my $str = "$d";
        str = str(d)
        str = d.to_s

Return the stringification of the matched value. Stringification
depends on the search flags, for file list entries it will return
just the base name unless SEARCH_FILES is used, for checksums
it will return an empty string unless SEARCH_CHECKSUMS is used.
Numeric values are currently stringified to an empty string.


THE SELECTION CLASS
-------------------
Selections are a way to easily deal with sets of packages.
There are multiple constructors to create them, the most useful
is probably the select() method in the Pool class.

=== CONSTANTS ===

*SELECTION_NAME*::
  Create the selection by matching package names

*SELECTION_PROVIDES*::
  Create the selection by matching package provides

*SELECTION_FILELIST*::
  Create the selection by matching package files

*SELECTION_CANON*::
  Create the selection by matching the canonical representation
  of the package. This is normally a combination of the name,
  the version, and the architecture of a package.

*SELECTION_DOTARCH*::
  Allow an ``.<architecture>'' suffix when matching names or
  provides.
 
*SELECTION_REL*::
  Allow the specification of a relation when matching names
  or provides, e.g. "name >= 1.2".

*SELECTION_INSTALLED_ONLY*::
  Limit the package search to installed packages.

*SELECTION_SOURCE_ONLY*::
  Limit the package search to source packages only.

*SELECTION_WITH_SOURCE*::
  Extend the package search to also match source packages. The
  default is only to match binary packages.

*SELECTION_GLOB*::
  Allow glob matching for package names, package provides, and
  file names.

*SELECTION_NOCASE*::
  Ignore case when matching package names, package provides,
  and file names.

*SELECTION_FLAT*::
  Return only one selection element describing the selected packages.
  The default is to create multiple elements for all globbed packages.
  Multiple elements are useful if you want to turn the selection into
  an install job, in that case you want an install job for every
  globbed package.

=== ATTRIBUTES ===

        Pool *pool;                             /* read only */
        $d->{'pool'}
        d.pool
        d.pool

Back pointer to pool.

=== METHODS ===

        int flags();
        my $flags = $sel->flags();
        flags = sel.flags()
        flags = sel.flags()

Return the result flags of the selection. The flags are a subset
of the ones used when creating the selection, they describe which
method was used to get the result. For example, if you create the
selection with ``SELECTION_NAME | SELECTION_PROVIDES'', the resulting
flags will either be SELECTION_NAME or SELECTION_PROVIDES depending
if there was a package that matched the name or not. If there was
no match at all, the flags will be zero.

        bool isempty();
        $sel->isempty()
        sel.isempty()
        sel.isempty?

Return true if the selection is empty, i.e. no package could be matched.

        void filter(Selection *other)
        $sel->filter($other);
        sel.filter(other)
        sel.filter(other)

Intersect two selections. Packages will only stay in the selection if there
are also included in the other selecting. Does an in-place modification.

        void add(Selection *other)
        $sel->add($other);
        sel.add(other)
        sel.add(other)

Build the union of two selections. All packages of the other selection will
be added to the set of packages of the selection object. Does an in-place
modification. Note that the selection flags are no longer meaningful after the
add operation.

        void add_raw(Id how, Id what)
        $sel->add_raw($how, $what);
        sel.add_raw(how, what)
        sel.add_raw(how, what)

Add a raw element to the selection. Check the Job class for information about
the how and what parameters.

        Job *jobs(int action)
        my @jobs = $sel->jobs($action);
        jobs = sel.jobs(action)
        jobs = sel.jobs(action)

Convert a selection into an array of Job objects. The action parameter is or-ed
to the ``how'' part of the job, it describes the type of job (e.g. install,
erase). See the Job class for the action and action modifier constants.

        Solvable *solvables()
        my @solvables = $sel->solvables();
        solvables = sel.solvables()
        solvables = sel.solvables()

Convert a selection into an array of Solvable objects.

        <stringification>
        my $str = "$sel";
        str = str(sel)
        str = sel.to_s

Return a string describing the selection.

THE JOB CLASS
-------------
Jobs are the way to specify to the dependency solver what to do.
Most of the times jobs will get created by calling the jobs() method
on a Selection object, but there is also a Job() constructor in the
Pool class.

=== CONSTANTS ===

Selection constants:

*SOLVER_SOLVABLE*::
  The ``what'' part is the id of a solvable.

*SOLVER_SOLVABLE_NAME*::
  The ``what'' part is the id of a package name.

*SOLVER_SOLVABLE_PROVIDES*::
  The ``what'' part is the id of a package provides.

*SOLVER_SOLVABLE_ONE_OF*::
  The ``what'' part is an offset into the ``whatprovides'' data, created
  by calling the towhatprovides() pool method.

*SOLVER_SOLVABLE_REPO*::
  The ``what'' part is the id of a repository.

*SOLVER_SOLVABLE_ALL*::
  The ``what'' part is ignored, all packages are selected.

*SOLVER_SOLVABLE_SELECTMASK*::
  A mask containing all the above selection bits.

Action constants:

*SOLVER_NOOP*::
  Do nothing.

*SOLVER_INSTALL*::
  Install a package of the specified set of packages. It tries to install
  the best matching package (i.e. the highest version of the packages from
  the repositories with the highest priority).

*SOLVER_ERASE*::
  Erase all of the packages from the specified set. If a package is not
  installed, erasing it will keep it from getting installed.

*SOLVER_UPDATE*::
  Update the matching installed packages to their best version. If none
  of the specified packages are installed, try to update the installed
  packages to the specified versions. See the section about targeted
  updates about more information.
  
*SOLVER_WEAKENDEPS*::
  Allow to break the dependencies of the matching packages. Handle with care.

*SOLVER_MULTIVERSION*::
  Mark the matched packages for multiversion install. If they get to be installed
  because of some other job, the installation will keep the old version of the
  package installed (for rpm by using ``-i'' instead of ``-U'').

*SOLVER_LOCK*::
  Do not change the state of the matched packages, i.e. when they are installed
  they stay installed, if not they are not selected for installation.

*SOLVER_DISTUPGRADE*::
  Update the matching installed packages to the best version included in one
  of the repositories. After this operation, all come from one of the available
  repositories except orphaned packages. Orphaned packages are packages that
  have no relation to the packages in the repositories, i.e. no package in the
  repositories have the same name or obsolete the orphaned package.
  This action brings the installed packages in sync with the ones in the
  repository. It also turns of arch/vendor/version locking for the affected
  packages to simulate a fresh installation. This means that distupgrade can
  actually downgrade packages if only lower versions of a package are available
  in the repositories.

*SOLVER_DROP_ORPHANED*::
  Erase all the matching installed packages if they are orphaned. This only makes
  sense if there is a ``distupgrade all packages'' job. The default is to erase
  orphaned packages only if they block the installation of other packages.

*SOLVER_VERIFY*::
  Fix dependency problems of matching installed packages. The default is to ignore
  dependency problems for installed packages.

*SOLVER_USERINSTALLED*::
  The matching installed packages are considered to be installed by a user, thus
  not installed to fulfil some dependency. This is needed input for the calculation
  of unneeded packages for jobs that have the SOLVER_CLEANDEPS flag set.

*SOLVER_JOBMASK*::
  A mask containing all the above action bits.

Action modifier constants:

*SOLVER_WEAK*::
  Makes the job a weak job. The solver tries to fulfil weak jobs, but does not
  report a problem if it is not possible to do so.

*SOLVER_ESSENTIAL*::
  Makes the job an essential job. If there is a problem with the job, the solver
  will not propose to remove the job as one solution (unless all other solutions
  are also to remove essential jobs).

*SOLVER_CLEANDEPS*::
  The solver will try to also erase all packages dragged in through dependencies
  when erasing the package. This needs SOLVER_USERINSTALLED jobs to maximize user
  satisfaction.

*SOLVER_FORCEBEST*::
  Insist on the best package for install, update, and distupgrade jobs. If this
  flag is not used, the solver will use the second-best package if the best
  package cannot be installed for some reason. When this flag is used, the solver
  will generate a problem instead.

*SOLVER_TARGETED*::
  Forces targeted operation update and distupgrade jobs. See the section about
  targeted updates about more information.

Set constants.

*SOLVER_SETEV*::
  The job specified the exact epoch and version of the package set.

*SOLVER_SETEVR*::
  The job specified the exact epoch, version, and release of the package set.

*SOLVER_SETARCH*::
  The job specified the exact architecture of the packages from the set.

*SOLVER_SETVENDOR*::
  The job specified the exact vendor of the packages from the set.

*SOLVER_SETREPO*::
  The job specified the exact repository of the packages from the set.

*SOLVER_SETNAME*::
  The job specified the exact name of the packages from the set.

*SOLVER_NOAUTOSET*::
  Turn of automatic set flag generation for SOLVER_SOLVABLE jobs.

*SOLVER_SETMASK*::
  A mask containing all the above set bits.

See the section about set bits for more information.

=== ATTRIBUTES ===

        Pool *pool;                             /* read only */
        $job->{'pool'}
        d.pool
        d.pool

Back pointer to pool.

        Id how;                                 /* read/write */
        $job->{'how'}
        d.how
        d.how

Union of the selection, action, action modifier, and set flags.
The selection part describes the semantics of the ``what'' Id.

        Id what;                                /* read/write */
        $job->{'what'}
        d.what
        d.what

Id describing the set of packages, the meaning depends on the
selection part of the ``how'' attribute.

=== METHODS ===

        Solvable *solvables()
        my @solvables = $job->solvables();
        solvables = job.solvables()
        solvables = job.solvables()

Return the set of solvables of the job as an array of Solvable
objects.

        bool isemptyupdate();
        $job->isemptyupdate()
        job.isemptyupdate()
        job.isemptyupdate?

Convenience function to find out if the job describes an update
job with no matching packages, i.e. a job that does nothing.
Some package managers like ``zypper'' like to turn those jobs
into install jobs, i.e. an update of a not-installed package
will result into the installation of the package.

        <stringification>
        my $str = "$job";
        str = str(job)
        str = job.to_s

Return a string describing the job.

        <equality>
        if ($job1 == $job2)
        if job1 == job2:
        if job1 == job2

Two jobs are equal if they belong to the same pool and both the
``how'' and the ``what'' attributes are the same.

=== TARGETED UPDATES ===
Libsolv has two modes for upgrades and distupgrade: targeted and
untargeted. Untargeted mode means that the installed packages from
the specified set will be updated to the best version. Targeted means
that packages that can be updated to a package in the specified set
will be updated to the best package of the set.

Here's an example to explain the subtle difference. Suppose that
you have package A installed in version "1.1", "A-1.2" is available
in one of the repositories and there is also package "B" that
obsoletes package A.

An untargeted update of "A" will update the installed "A-1.1" to
package "B", because that is the newest version (B obsoletes A and
is thus newer).

A targeted update of "A" will update "A-1.1" to "A-1.2", as the
set of packages contains both "A-1.1" and "A-1.2", and "A-1.2" is
the newer one.

An untargeted update of "B" will do nothing, as "B" is not installed.

An targeted update of "B" will update "A-1.1" to "B".

Note that the default is to do "auto-targeting", thus if the specified
set of packages does not include an installed package, the solver
will assume targeted operation even if SOLVER_TARGETED is not used.

This mostly matches the intent of the user, with one exception: In
the example above, an update of "A-1.2" will update "A-1.1" to
"A-1.2" (targeted mode), but a second update of "A-1.2" will suddenly
update to "B", as untargeted mode is chosen because "A-1.2" is now
installed.

If you want to have full control over when targeting mode is chosen,
turn off auto-targeting with the SOLVER_FLAG_NO_AUTOTARGET solver option.
In that case, all updates are considered to be untargeted unless they
include the SOLVER_TARGETED flag.

=== SET BITS ===
Set bits specify which parts of the specified packages where specified
by the user. It is used by the solver when checking if an operation is
allowed or not. For example, the solver will normally not allow the
downgrade of an installed package. But it will not report a problem if
the SOLVER_SETEVR flag is used, as it then assumes that the user specified
the exact version and thus knows what he is doing.

So if a package "screen-1-1" is installed for the x86_64 architecture and
version "2-1" is only available for the i586 architecture, installing
package "screen-2.1" will ask the user for confirmation because of the
different architecture. When using the Selection class to create jobs
the set bits are automatically added, e.g. selecting ``screen.i586'' will
automatically add SOLVER_SETARCH, and thus no problem will be reported.

THE SOLVER CLASS
----------------
xxx

THE TRANSACTION CLASS
---------------------
xxx

CHECKSUMS
---------
Checksums (also called hashes) are used to make sure that downloaded data is
not corrupt and also as a fingerprint mechanism to check if data has changed.

=== CLASS METHODS ===

        Chksum *Chksum(Id type)
        my $chksum = solv::Chksum->new($type);
        chksum = solv.Chksum(type)
        chksum = Solv::Chksum.new(type)

Create a checksum object. Currently the following types are supported:

        REPOKEY_TYPE_MD5
        REPOKEY_TYPE_SHA1
        REPOKEY_TYPE_SHA256

These keys are constants in the *solv* class.

        Chksum *Chksum(Id type, const char *hex)
        my $chksum = solv::Chksum->new($type, $hex);
        chksum = solv.Chksum(type, hex)
        chksum = Solv::Chksum.new(type, hex)

Create an already finalized checksum object.

=== ATTRIBUTES ===

        Id type;                        /* read only */
        $chksum->{'type'}
        chksum.type
        chksum.type

Return the type of the checksum object.

=== METHODS ===

        void add(const char *str)
        $chksum->add($str);
        chksum.add(str)
        chksum.add(str)

Add a string to the checksum.

        void add_fp(FILE *fp)
        $chksum->add_fp($file);
        chksum.add_fp(file)
        chksum.add_fp(file)

Add the contents of a file to the checksum.
        
        void add_stat(const char *filename)
        $chksum->add_stat($filename);
        chksum.add_stat(filename)
        chksum.add_stat(filename)

Stat the file and add the dev/ino/size/mtime member to the checksum. If the
stat fails, the members are zeroed.

        void add_fstat(int fd)
        $chksum->add_fstat($fd);
        chksum.add_fstat(fd)
        chksum.add_fstat(fd)

Same as add_stat, but instead of the filename a file descriptor is used.

        unsigned char *raw()
        my $raw = $chksum->raw();
        raw = chksum.raw()
        raw = chksum.raw()

Finalize the checksum and return the result as raw bytes. This means that the
result can contain NUL bytes or unprintable characters.

        const char *hex()
        my $raw = $chksum->hex();
        raw = chksum.hex()
        raw = chksum.hex()

Finalize the checksum and return the result as hex string.

        <equality>
        if ($chksum1 == $chksum2)
        if chksum1 == chksum2:
        if chksum1 == chksum2

Checksums are equal if they are of the same type and the finalized results are
the same.

        <stringification>
        my $str = "$chksum";
        str = str(chksum)
        str = chksum.to_s

If the checksum is finished, the checksum is returned as "<type>:<hex>" string.
Otherwise "<type>:unfinished" is returned.


FILE MANAGEMENT
---------------
This functions were added because libsolv uses standard *FILE* pointers to
read/write files, but languages like perl have their own implementation of
files. The libsolv functions also support decompression and compression, the
algorithm is selected by looking at the file name extension.

        FILE *xfopen(char *fn, char *mode = "r")
        my $file = solv::xfopen($path);
        file = solv.xfopen(path)
        file = Solv::xfopen(path)

Open a file at the specified path. The `mode` argument is passed on to the
stdio library.

        FILE *xfopen_fd(char *fn, int fileno)
        my $file = solv::xfopen_fd($path, $fileno);
        file = solv.xfopen_fd(path, fileno)
        file = Solv::xfopen_fd(path, fileno)

Create a file handle from the specified file descriptor. The path argument is
only used to select the correct (de-)compression algorithm, use an empty path
if you want to make sure to read/write raw data.

=== METHODS ===

        int fileno()
        my $fileno = $file->fileno();
        fileno = file.fileno()
        fileno = file.fileno()

Return file file descriptor of the file. If the file is not open, `-1` is
returned.

        int dup()
        my $fileno = $file->dup();
        fileno = file.dup()
        fileno = file.dup()

Return a copy of the descriptor of the file. If the file is not open, `-1` is
returned.

        bool flush()
        $file->flush();
        file.flush()
        file.flush()

Flush the file. Returns false if there was an error. Flushing a closed file
always returns true.

        bool close()
        $file->close();
        file.close()
        file.close()

Close the file. This is needed for languages like Ruby, that do not destruct
objects right after they are no longer referenced. In that case, it is good
style to close open files so that the file descriptors are freed right away.
Returns false if there was an error.

THE REPODATACLASS
-----------------
xxx

Author
------
Michael Schroeder <mls@suse.de>