#!/usr/bin/python -tt
# skvidal@linux.duke.edu
# process kernel and kernel-smp packages and hand back n-v-r info on
# the oldest ones barring:
# - current running one and the newest 2


import rpm
import sys
import os


def get_running_kernel_package_info():
    ver = os.uname()[2]
    kernfile = '/boot/vmlinuz-%s' % ver
    ts = rpm.TransactionSet()
    mi = ts.dbMatch('basenames', kernfile)
    num = mi.count()
    if num == 0:
        return None
    else:
        hdr = mi.next()
        return (hdr['name'], hdr['version'], hdr['release'])

def sorthdrs(hdr1, hdr2):
    rc = rpm.versionCompare(hdr1, hdr2)
    if rc < 0:
        return -1
    elif rc == 0:
        return 0
    elif rc > 0:
        return 1


def main():
    runname, runver, runrel = get_running_kernel_package_info()
    runstring = '%s-%s-%s' % (runname, runver, runrel)
    ts = rpm.TransactionSet()
    oldlist = []
    for pkgname in ['kernel', 'kernel-smp', 'kernel-enterprise'
                    'kernel-hugmem', 'kernel-bigmem']:
        mi = ts.dbMatch('name', pkgname)
        thislist = []
        if mi.count() > 1:
            kernlist = []
            for hdr in mi:
                thislist.append(hdr)
            thislist.sort(sorthdrs)
            for hdr in thislist[:-2]:
                kstring = '%s-%s-%s' % (hdr['name'], hdr['version'], hdr['release'])
                if kstring != runstring:
                    oldlist.append(kstring)
       
    # get the list of all the older kernels
    # iterate them and remove our running kernel
    # return n-v-r on the line for handing off to yum

    for item in oldlist:
        print ' %s' % item
    
    
if __name__ == "__main__":
    main()