# A plugin for yum which only leaves n 'kernel' packages installed instead

# of infinitely doing installonly

#

# Copyright 2005  Red Hat, Inc.

# Jeremy Katz <katzj@redhat.com>

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# version 0.93

import os

from rpmUtils import miscutils

from yum.plugins import TYPE_CORE

from yum.packages import YumInstalledPackage, comparePoEVR

requires_api_version = '2.4'

plugin_type = TYPE_CORE

def get_running_kernel_version_release():

    """This takes the output of uname and figures out the (version, release)

    tuple for the running kernel."""

    ver = os.uname()[2]

    for s in ("bigmem", "enterprise", "smp", "hugemem", "PAE", "rt",

              "guest", "hypervisor", "xen0", "xenU", "xen", "debug"):

        if ver.endswith(s):

            ver = ver.replace(s, "")

    if ver.find("-") != -1:

        (v, r) = ver.split("-", 1)

        return (v, r)

    return (None, None)

def config_hook(conduit):

    global num_tokeep

    num_tokeep = conduit.confInt('main', 'tokeep', default=2)

def postresolve_hook(conduit):

    ts = conduit.getTsInfo()

    rpmdb = conduit.getRpmDB()

    conf = conduit.getConf()

    mems = ts.getMembers()

    toremove = []

    for instpkg in conf.installonlypkgs:

        for m in mems:

            if (m.name == instpkg or instpkg in m.po.provides_names) \

                   and m.ts_state in ('i', 'u'):

                installed = rpmdb.searchNevra(name=m.name)

                if len(installed) >= num_tokeep - 1: # since we're adding one

                    numleft = len(installed) - num_tokeep + 1

                    (curv, curr) = get_running_kernel_version_release()

                    installed.sort(comparePoEVR)

                    for po in installed:

                        if (po.version, po.release) == (curv, curr): 

                            # don't remove running

                            continue

                        if numleft == 0:

                            break

                        toremove.append(po)

                        numleft -= 1

    map(lambda x: ts.addErase(x), toremove)