src/lxc/lxc-ps.in

   1 #!/usr/bin/perl
   2 #
   3 # lxc-ps
   4 #
   5 # Authors:
   6 # Daniel Lezcano <daniel.lezcano@free.fr>
   7
   8 # This library is free software; you can redistribute it and/or
   9 # modify it under the terms of the GNU Lesser General Public
  10 # License as published by the Free Software Foundation; either
  11 # version 2.1 of the License, or (at your option) any later version.
  12
  13 # This library is distributed in the hope that it will be useful,
  14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 # Lesser General Public License for more details.
  17
  18 # You should have received a copy of the GNU Lesser General Public
  19 # License along with this library; if not, write to the Free Software
  20 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21
  22 #
  23 # This script allows to
  24 # display processes information with related container name if available.
  25 #
  26 use strict;
  27
  28
  29 # Some globals
  30
  31 our $PS_HEADERS;      # String containing headers of the ps output
  32 our $PS_PID_INDEX;    # Index of the PID column in the ps headers
  33 our @PS_LINES;        # Output lines of the ps command
  34
  35 our $LXC_DISPLAY = 0; # By default do not display container information
  36 our %LXC_NAMES;       # Specified container names (if any)
  37
  38 sub get_container_names {
  39         my $ref_names = shift;
  40         my $lxcpath='@LXCPATH@';
  41
  42         open(active, "netstat -xa | grep $lxcpath |") or return;
  43         while(<active>) {
  44                 chomp;
  45                 s#.*$lxcpath/(.*)/command.*#$1#;
  46                 push @$ref_names, $_;
  47         }
  48         close active;
  49 }
  50
  51 sub get_cgroup {
  52         my $ref_cgroup = shift;
  53         my $mount_string;
  54
  55         $mount_string=`mount -t cgroup |grep -E -e '^lxc '`;
  56         unless ($mount_string) {
  57                 $mount_string=`mount |grep -m1 'type cgroup'`;
  58         }
  59         chomp($mount_string);
  60         if ($mount_string) {
  61                 $$ref_cgroup=`echo "$mount_string" |cut -d' ' -f3`;
  62                 chomp($$ref_cgroup);
  63         }
  64         die "unable to find mounted cgroup" unless $$ref_cgroup;
  65 }
  66
  67 sub get_pids_in_containers {
  68         my $ref_names = shift;
  69         my $ref_cgroup = shift;
  70         my $ref_pids = shift;
  71         my @pidlist;
  72
  73         for (@{$ref_names}) {
  74                 my $task_file = "$$ref_cgroup/$_/tasks";
  75
  76                 $LXC_NAMES{$_} = 1;
  77                 open(tasks, "cat $task_file 2>/dev/null |") or next;
  78                 while (<tasks>) {
  79                         chomp $_;
  80                         push @pidlist, $_;
  81                 }
  82                 close tasks;
  83         }
  84         $$ref_pids = join(',', @pidlist);
  85 }
  86
  87 sub reclaim_pid_index {
  88     my @headers = split " ", $PS_HEADERS;
  89     for my $i (0 .. $#headers) {
  90         if ($headers[$i] eq "PID") {
  91             $PS_PID_INDEX = $i;
  92             return;
  93         }
  94     }
  95     print "Cannot find ps PID column !\n";
  96     exit 1;
  97 }
  98
  99 sub execute_ps {
 100     open(ps, "ps @_ |") or die "Cannot execute ps command: $!\n";
 101
 102     $PS_HEADERS = <ps>;
 103     reclaim_pid_index;
 104
 105     while (<ps>) {
 106         push @PS_LINES, $_;
 107     }
 108     close ps;
 109 }
 110
 111 sub get_container {
 112     my $pid = shift;
 113     my $filename = "/proc/$pid/cgroup";
 114     open(LXC, "$filename");
 115     my $container = <LXC>;
 116     close LXC;
 117     chomp($container);
 118     if ($container =~ m/[:,]ns[:,]/o) {
 119         $container =~ s/.*:\///o;
 120     } else {
 121         $container ='';
 122     }
 123     return $container;
 124 }
 125
 126 sub display_headers {
 127     printf "%-10s %s", "CONTAINER", $PS_HEADERS;
 128 }
 129
 130 sub display_usage {
 131     print <<EOF;
 132 Usage: lxc-ps [--help] [--usage] [--name NAME...] [--lxc] [ps options]
 133 EOF
 134 }
 135
 136 sub display_help {
 137     display_usage;
 138     print <<EOF;
 139
 140 Display processes information with related container name if available.
 141
 142 Options:
 143 --help     Display this help.
 144 --usage    Display the command usage.
 145 --name     Display processes related to given containers.
 146            Containers are identified by a comma separated list of
 147            their names.
 148 --lxc      Display processes related to all lxc containers.
 149
 150 Other available options correspond to the ps ones, see the ps manual
 151 or try a 'ps --help' for further details.
 152 EOF
 153 }
 154
 155 use Getopt::Long qw(:config no_auto_abbrev pass_through);
 156
 157 my $arg_help  = '';
 158 my $arg_usage = '';
 159 my $arg_lxc   = '';
 160 my @arg_name;
 161
 162 GetOptions('help'   => \$arg_help,
 163            'usage'  => \$arg_usage,
 164            'lxc'    => \$arg_lxc,
 165            'name=s' => \@arg_name);
 166
 167 @arg_name = split(/,/, join(',', @arg_name));
 168
 169 # Some help
 170 if ($arg_help)  {display_help; exit 0;}
 171 if ($arg_usage) {display_usage; exit 0;}
 172
 173 # Should we filter processes related to containers
 174 if ($arg_lxc) {
 175         $LXC_DISPLAY = 1;
 176         get_container_names \@arg_name;
 177 }
 178 if (@arg_name > 0) {
 179         my $cgroup;
 180         my $pid_list;
 181         $LXC_DISPLAY = 2;
 182
 183         get_cgroup \$cgroup;
 184         get_pids_in_containers(\@arg_name, \$cgroup, \$pid_list);
 185         if ($pid_list) {
 186                 @ARGV = ("-p $pid_list",@ARGV);
 187         }
 188 }
 189
 190 execute_ps @ARGV;
 191
 192 display_headers;
 193 for (@PS_LINES) {
 194     my @a = split;
 195     my $container = get_container $a[$PS_PID_INDEX];
 196     if ($LXC_DISPLAY == 2 and not $LXC_NAMES{$container}) {next;}
 197     if ($LXC_DISPLAY == 1 and $container eq '') {next;}
 198     printf "%-10s %s", $container, $_;
 199 }
 200
 201 exit 0;