#!/usr/bin/env python
# -*- python-mode -*-
"""Script to set NFS debug levels symbolically
"""

__copyright__ = """
Copyright (C) 2007, Chuck Lever <chuck.lever@oracle.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License version 2 as
published by the Free Software Foundation.

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.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
"""

""" History:
Thu Jun 21 10:41:40 EDT 2007 cel - created
"""

import sys, os, time, popen2

""" From include/linux/nfs_fs.h
"""
NfsDebugFlags = {
    'vfs'         : 0x0001,
    'dircache'    : 0x0002,
    'lookupcache' : 0x0004,
    'pagecache'   : 0x0008,
    'proc'        : 0x0010,
    'xdr'         : 0x0020,
    'file'        : 0x0040,
    'root'        : 0x0080,
    'callback'    : 0x0100,
    'client'      : 0x0200,
    'mount'       : 0x0400,
}

NoNfsFlags = 0
AllNfsFlags = 0x07ff

def DoCmd(cmd):
    p = popen2.Popen3(cmd, True)
    output = p.fromchild.read()
    if p.wait():
        print '%s failed (%s)' % (str(cmd), p.childerr.read().strip())
    return output

def CurrentSetting():
    string = DoCmd("/sbin/sysctl sunrpc.nfs_debug")
    words = string.split()
    return int(words[2])

def SetNfsFlags(flags):
    cmd = '/usr/bin/sudo /sbin/sysctl -w sunrpc.nfs_debug=%d' % flags
    DoCmd(cmd)
    return

def ProcessFlag(flag):
    if flag not in NfsDebugFlags:
        print 'Unrecognized NFS debugging flag.'
        return

    current = CurrentSetting()
    SetNfsFlags(current | NfsDebugFlags[flag])

    return


#
# Main
#

if len(sys.argv) == 1:
    current = CurrentSetting()
    if current == NoNfsFlags:
        print 'NFS debugging is currently disabled.'
    elif current == AllNfsFlags:
        print 'NFS debugging is currently fully enabled.'
    else:
        print 'Current NFS debugging flags:'
        for i in NfsDebugFlags.items():
            if (current & i[1]) == i[1]:
                 print '   %s' % i[0]
    sys.exit(0)

if sys.argv[1] in [ '-h', '--help' ]:
    print 'Usage:  nfsdebug [flag name] [flag name] ...'
    print '  where flag name is one of: all, none, %s' % \
        ', '.join(NfsDebugFlags.keys())
    sys.exit(1)

for arg in sys.argv:
    if arg == sys.argv[0]:
        continue

    elif arg in [ 'all', 'on', 'true', 'yes' ]:
        SetNfsFlags(AllNfsFlags)
        print 'NFS debugging is now enabled.'

    elif arg in [ 'none', 'off', 'false', 'no', 'clear', 'zero' ]:
        SetNfsFlags(NoNfsFlags)
        print 'NFS debugging is now disabled.'

    else:
        ProcessFlag(arg)

sys.exit(0)