#!/usr/bin/env perl
# IBM(c) 2007 EPL license http://www.eclipse.org/legal/epl-v10.html

package xCAT::DSHCLI;

use File::Basename;

use locale;

use File::Path;
use POSIX;
use Socket;
use Getopt::Long;
require xCAT::DSHCore;
use xCAT::MsgUtils;
use xCAT::Utils;
use xCAT::Table;
use lib '/opt/xcat/xdsh';
our @dsh_available_contexts = ();
our @dsh_valid_contexts     = ();

our $dsh_exec_state         = 0;
our $dsh_forked_process     = undef;
our $dsh_options            = undef;
our $dsh_resolved_targets   = undef;
our $dsh_unresolved_targets = undef;
our %dsh_target_status      = undef;
our $dsh_trace              = undef;
our %dsh_stats              = ();
our $signal_interrupt_flag  = 0;
our $dsh_cmd_background     = 0;
$::CONTEXT_DIR = "/opt/xcat/xdsh/Context/";
$::__DCP_DELIM = 'Xcat,DELIMITER,Xcat';

our @dsh_valid_env = (
                      'DCP_NODE_OPTS',      'DCP_NODE_RCP',
                      'DSH_CONTEXT',        'DSH_ENVIRONMENT',
                      'DSH_FANOUT',         'DSH_LOG',
                      'DSH_NODEGROUP_PATH', 'DSH_NODE_LIST',
                      'DSH_NODE_OPTS',      'DSH_NODE_RCP',
                      'DSH_NODE_RSH',       'DSH_OUTPUT',
                      'DSH_PATH',           'DSH_SYNTAX',
                      'DSH_TIMEOUT',
                      );
select(STDERR);
$| = 1;
select(STDOUT);
$| = 1;

#----------------------------------------------------------------------------

=head3
        execute_dcp

        This is the main driver routine for an instance of the dcp command.
        Given the options configured in the $options hash table, the routine
        configures the execution of the dcp instance, executes the remote copy
        commands and processes the output from each target.

        Arguments:
			$options - options hash table describing dcp configuration options

        Returns:
        	The number of targets that failed to execute a remote copy command

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub execute_dcp
{
    my ($class, $options) = @_;

    $::dsh_command = 'dcp';

    my $result = xCAT::DSHCLI->config_dcp($options);
    $result && (return $result);

    my %resolved_targets   = ();
    my %unresolved_targets = ();
    my %context_targets    = ();
    xCAT::DSHCLI->resolve_targets($options, \%resolved_targets,
                                  \%unresolved_targets, \%context_targets);

    if (!scalar(%resolved_targets))
    {
        my %rsp;
        $rsp->{data}->[0] = "No hosts in node list";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK, 1);
        return ++$result;
    }

    $$options{'verify'}
      && xCAT::DSHCLI->verify_targets($options, \%resolved_targets);

    #check if file descriptor number exceeds the max number in ulimit
    #if (
    #     xCAT::DSHCLI->isFdNumExceed(
    #                          2, scalar(keys(%resolved_targets)),
    #                          $$options{'fanout'}
    #    )
    # )
    #{
    #    my %rsp;
    #    $rsp->{data}->[0] = " The DSH fanout value has exceeded the system file descriptor upper limit. Please either reduce the fanout value, or increase max file descriptor number by running ulimit.";
    #    xCAT::MsgUtils->message("E", $rsp, $::CALLBACK, 1);
    #   return ++$result;
    #}

    my @targets_waiting  = (sort keys(%resolved_targets));
    my %targets_active   = ();
    my @targets_finished = ();
    my @targets_failed   = ();
    my %targets_buffered = ();

    my %output_buffers = ();
    my %error_buffers  = ();
    my %pid_targets    = ();
    my %outfh_targets  = ();
    my %errfh_targets  = ();
    my %forked_process = ();

    my @output_files = ();
    !$$options{'silent'} && push @output_files, *STDOUT;
    my @error_files = ();
    !$$options{'silent'} && push @error_files, *STDERR;

    xCAT::DSHCLI->fork_fanout_dcp(
                                  $options,          \%resolved_targets,
                                  \%forked_process,  \%pid_targets,
                                  \%outfh_targets,   \%errfh_targets,
                                  \@targets_waiting, \%targets_active
                                  );

    while (keys(%targets_active))
    {
        my $rin = $outfh_targets{'bitmap'} | $errfh_targets{'bitmap'};

        my $fh_count =
          select(my $rout = $rin, undef, undef, $$options{'timeout'});

        if ($fh_count == 0)
        {
            my @active_list = keys(%targets_active);
            my %rsp;
            $rsp->{data}->[0] =
              " Timed out waiting for response from child processes for the following nodes.";
            $rsp->{data}->[1] = " @active_list";
            xCAT::MsgUtils->message("E", $rsp, $::CALLBACK, 1);
            kill 'INT', keys(%pid_targets);
            $result++;
            last;
        }

        my @select_out_fhs =
          xCAT::DSHCLI->util_bit_indexes($rout & $outfh_targets{'bitmap'}, 1);

        (@select_out_fhs)
          && xCAT::DSHCLI->buffer_output(
                     $options,           \%resolved_targets, \%targets_active,
                     \@targets_finished, \@targets_failed,   \%targets_buffered,
                     \%pid_targets,      \%forked_process,   \%outfh_targets,
                     \%output_buffers,   \%error_buffers,    \@output_files,
                     \@error_files,      \@select_out_fhs
                     );

        my @select_err_fhs =
          xCAT::DSHCLI->util_bit_indexes($rout & $errfh_targets{'bitmap'}, 1);

        (@select_err_fhs)
          && xCAT::DSHCLI->buffer_error(
                                        $options,         \%resolved_targets,
                                        \%targets_active, \@targets_finished,
                                        \@targets_failed, \%targets_buffered,
                                        \%pid_targets,    \%forked_process,
                                        \%errfh_targets,  \%output_buffers,
                                        \%error_buffers,  \@output_files,
                                        \@error_files,    \@select_err_fhs
                                        );

        my @targets_buffered_keys = sort keys(%targets_buffered);

        foreach $user_target (@targets_buffered_keys)
        {
            my $target_properties = $$resolved_targets{$user_target};

            if (!$$options{'silent'})
            {
                if ($::DCP_API)
                {
                    $::DCP_API_MESSAGE .=
                        join("", @{$output_buffers{$user_target}})
                      . join("", @{$error_buffers{$user_target}});
                    if ($$options{'display_output'})
                    {
                        print STDOUT @{$output_buffers{$user_target}};
                        print STDERR @{$error_buffers{$user_target}};
                    }
                }
                else
                {
                    print STDOUT @{$output_buffers{$user_target}};
                    print STDERR @{$error_buffers{$user_target}};
                }
            }

            delete $output_buffers{$user_target};
            delete $error_buffers{$user_target};

            my $exit_code = $targets_buffered{$user_target}{'exit-code'};

            if ($exit_code != 0)
            {
                push @targets_failed, $user_target;
                push @{$dsh_target_status{'failed'}}, $user_target;

            }

            else
            {
                push @targets_finished, $user_target;
            }

            delete $targets_buffered{$user_target};
        }

        (@targets_waiting)
          && xCAT::DSHCLI->fork_fanout_dcp(
                        $options,          \%resolved_targets, \%forked_process,
                        \%pid_targets,     \%outfh_targets,    \%errfh_targets,
                        \@targets_waiting, \%targets_active
                        );
    }

    return (scalar(@targets_failed) + scalar(keys(%unresolved_targets)));
}

#----------------------------------------------------------------------------

=head3
        execute_dsh

        This is the main driver routine for an instance of the dsh command.
        Given the options configured in the $options hash table, the routine
        configures the execution of the dsh instance, executes the remote shell
        commands and processes the output from each target.

        Arguments:
			$options - options hash table describing dsh configuration options

        Returns:
        	The number of targets that failed to execute a remote shell command

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub execute_dsh
{
    my ($class, $options) = @_;

    $::dsh_command = 'dsh';
    $dsh_options   = $options;

    xCAT::DSHCLI->config_signals_dsh($options);

    my %rsp;
    $rsp->{data}->[0] = "dsh>  Dsh_process_id $$";
    $$options{'monitor'} && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
    $dsh_exec_state++;

    my $result = xCAT::DSHCLI->config_dsh($options);
    $result && (return $result);

    my %rsp;
    $rsp->{data}->[0] = "dsh>  Dsh_initialization_completed";
    $$options{'monitor'} && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
    $dsh_exec_state++;

    my %resolved_targets = ();
    $dsh_resolved_targets = \%resolved_targets;
    my %unresolved_targets = ();
    $dsh_unresolved_targets = \%unresolved_targets;
    my %context_targets = ();
    xCAT::DSHCLI->resolve_targets($options, \%resolved_targets,
                                  \%unresolved_targets, \%context_targets);
    my @canceled_targets = ();
    $dsh_target_status{'canceled'} = \@canceled_targets;

    if (scalar(%unresolved_targets))
    {
        foreach $target (sort keys(%unresolved_targets))
        {
            my %rsp;
            $rsp->{data}->[0] = "dsh>  Remote_command_cancelled $target";
            $$dsh_options{'monitor'}
              && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
        }
    }

    if (!scalar(%resolved_targets))
    {
        my %rsp;
        $rsp->{data}->[0] = " No hosts in node list";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK, 1);
        return ++$result;
    }
    $dsh_exec_state++;

    if ($$options{'verify'})
    {
        my %rsp;
        $rsp->{data}->[0] = "dsh>  Dsh_verifying_hosts";
        $$options{'monitor'} && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
        xCAT::DSHCLI->verify_targets($options, \%resolved_targets);
    }

    #check if file descriptor number exceeds the max number in ulimit
    #if (
    #    xCAT::DSHCLI->isFdNumExceed(
    #                        2, scalar(keys(%resolved_targets)),
    #                       $$options{'fanout'}
    # )
    #)
    #{
    #    my %rsp;
    #    $rsp->{data}->[0] = " The DSH fanout value has exceeded the system file descriptor upper limit. Please either reduce the fanout value, or increase max file descriptor number by running ulimit.";
    #    xCAT::MsgUtils->message("E", $rsp, $::CALLBACK, 1);
    #   return ++$result;
    #}

    my @targets_failed = ();
    $dsh_target_status{'failed'} = \@targets_failed;
    @targets_failed =
      xCAT::DSHCLI->_execute_dsh($options, \%resolved_targets,
                                 \%unresolved_targets, \%context_targets);
    if ($::DSH_API)
    {
        if (scalar(@targets_failed) > 0)
        {
            $::DSH_API_NODES_FAILED = join ",", @targets_failed;
        }
    }
    return (scalar(@targets_failed) + scalar(keys(%unresolved_targets)));
}

#----------------------------------------------------------------------------

=head3
        _execute_dsh

        Wrapper routine for execute_dsh and execute_dsh_interactive
        to execute actual dsh call

        Arguments:
        	$options - options hash table describing dsh configuration options
        	$resolved_targets - hash table of resolved targets and target properties
        	$unresolved_targets - hash table of unresolved targets and relevant properties
			$context_targets - hash table of targets grouped by context name

        Returns:
        	@targets_failed - a list of those targets that failed execution

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:
        	Internal Routine only

=cut

#----------------------------------------------------------------------------
sub _execute_dsh
{
    my ($class, $options, $resolved_targets, $unresolved_targets,
        $context_targets)
      = @_;

    my @output_files = ();
    !$$options{'silent'} && push @output_files, *STDOUT;

    my @error_files = ();
    !$$options{'silent'} && push @error_files, *STDERR;

    my @targets_waiting = (sort keys(%$resolved_targets));
    $dsh_target_status{'waiting'} = \@targets_waiting;
    my %targets_active = ();
    $dsh_target_status{'active'} = \%targets_active;
    my @targets_finished = ();
    $dsh_target_status{'finished'} = \@targets_finished;
    my @targets_failed   = ();
    my %targets_buffered = ();

    my %output_buffers = ();
    my %error_buffers  = ();
    my %pid_targets    = ();
    my %outfh_targets  = ();
    my %errfh_targets  = ();
    my %forked_process = ();
    $dsh_forked_process = \%forked_process;

    my %rsp;
    $rsp->{data}->[0] = "dsh>  Dsh_remote_execution_started";
    $$options{'monitor'} && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
    $dsh_exec_state++;

    xCAT::DSHCLI->fork_fanout_dsh(
                                  $options,          $resolved_targets,
                                  \%forked_process,  \%pid_targets,
                                  \%outfh_targets,   \%errfh_targets,
                                  \@targets_waiting, \%targets_active
                                  );

    while (keys(%targets_active))
    {

        my $rin = $outfh_targets{'bitmap'} | $errfh_targets{'bitmap'};

        my $fh_count =
          select(my $rout = $rin, undef, undef, $$options{'timeout'});

        if ($fh_count == 0)
        {
            my @active_list = keys(%targets_active);
            my %rsp;
            $rsp->{data}->[0] =
              " Timed out waiting for response from child processes for the followint nodes. Terminating the child processes. ";
            $rsp->{data}->[1] = " @active_list";
            xCAT::MsgUtils->message("E", $rsp, $::CALLBACK, 1);
            @targets_failed = keys(%targets_active);

            &handle_signal_dsh('INT', 1);
            $result++;
            last;
        }

        my @select_out_fhs =
          xCAT::DSHCLI->util_bit_indexes($rout & $outfh_targets{'bitmap'}, 1);

        if (@select_out_fhs)
        {
            if ($$options{'streaming'})
            {
                xCAT::DSHCLI->stream_output(
                        $options,           $resolved_targets, \%targets_active,
                        \@targets_finished, \@targets_failed,  \%pid_targets,
                        \%forked_process,   \%outfh_targets,   \%output_buffers,
                        \@output_files,     \@select_out_fhs
                        );
            }

            else
            {
                xCAT::DSHCLI->buffer_output(
                      $options,           $resolved_targets, \%targets_active,
                      \@targets_finished, \@targets_failed,  \%targets_buffered,
                      \%pid_targets,      \%forked_process,  \%outfh_targets,
                      \%output_buffers,   \%error_buffers,   \@output_files,
                      \@error_files,      \@select_out_fhs
                      );
            }
        }

        my @select_err_fhs =
          xCAT::DSHCLI->util_bit_indexes($rout & $errfh_targets{'bitmap'}, 1);

        if (@select_err_fhs)
        {
            if ($$options{'streaming'})
            {
                xCAT::DSHCLI->stream_error(
                        $options,           $resolved_targets, \%targets_active,
                        \@targets_finished, \@targets_failed,  \%pid_targets,
                        \%forked_process,   \%errfh_targets,   \%error_buffers,
                        \@error_files,      \@select_err_fhs
                        );
            }

            else
            {
                xCAT::DSHCLI->buffer_error(
                      $options,           $resolved_targets, \%targets_active,
                      \@targets_finished, \@targets_failed,  \%targets_buffered,
                      \%pid_targets,      \%forked_process,  \%errfh_targets,
                      \%output_buffers,   \%error_buffers,   \@output_files,
                      \@error_files,      \@select_err_fhs
                      );
            }
        }

        my @targets_buffered_keys = sort keys(%targets_buffered);

        foreach $user_target (@targets_buffered_keys)
        {
            my $target_properties = $$resolved_targets{$user_target};

            my $output_file     = undef;
            my $output_filename = undef;
            my $error_file      = undef;
            my $error_filename  = undef;

            if (!$$options{'silent'})
            {
                if ($::DSH_API)
                {
                    $::DSH_API_MESSAGE =
                        $::DSH_API_MESSAGE
                      . join("", @{$output_buffers{$user_target}})
                      . join("", @{$error_buffers{$user_target}});
                    if ($$options{'display_output'})
                    {
                        print STDOUT @{$output_buffers{$user_target}};
                        print STDERR @{$error_buffers{$user_target}};
                    }
                }
                else
                {
                    print STDOUT @{$output_buffers{$user_target}};
                    print STDERR @{$error_buffers{$user_target}};
                }
            }

            delete $output_buffers{$user_target};
            delete $error_buffers{$user_target};

            my $exit_code = $targets_buffered{$user_target}{'exit-code'};
            my $target_rc = $targets_buffered{$user_target}{'target-rc'};

            if ($exit_code != 0)
            {

                my %rsp;
                $rsp->{data}->[0] =
                  " $user_target remote Command return code = $exit_code.";
                xCAT::MsgUtils->message("E", $rsp, $::CALLBACK, 1);

                my %rsp;
                $rsp->{data}->[0] = "dsh>  Remote_command_failed $user_target";
                $$options{'monitor'}
                  && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                push @targets_failed, $user_target;
                push @{$dsh_target_status{'failed'}}, $user_target
                  if !$signal_interrupt_flag;

            }

            else
            {
                if ($target_rc != 0)
                {

                    my %rsp;
                    $rsp->{data}->[0] =
                      " $user_target remote Command return code = $$target_properties{'target-rc'}.";
                    xCAT::MsgUtils->message("E", $rsp, $::CALLBACK, 1);

                    my %rsp;
                    $rsp->{data}->[0] =
                      "dsh>  Remote_command_failed $user_target";
                    $$options{'monitor'}
                      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK, 1);

                    push @targets_failed, $user_target;
                    push @{$dsh_target_status{'failed'}}, $user_target
                      if !$signal_interrupt_flag;
                }

                elsif (!defined($target_rc) && !$dsh_cmd_background)
                {

                    my %rsp;
                    $rsp->{data}->[0] =
                      " A return code for the command run on the host $isre_target was not received.";
                    xCAT::MsgUtils->message("E", $rsp, $::CALLBACK, 1);
                    my %rsp;
                    $rsp->{data}->[0] =
                      "dsh>  Remote_command_failed $user_target";
                    $$options{'monitor'}
                      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                    push @targets_failed, $user_target;
                    push @{$dsh_target_status{'failed'}}, $user_target
                      if !$signal_interrupt_flag;
                }

                else
                {
                    my %rsp;
                    $rsp->{data}->[0] =
                      "dsh>  Remote_command_successful $user_target";
                    $$options{'monitor'}
                      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                    push @targets_finished, $user_target;
                }
            }

            delete $targets_buffered{$user_target};
        }

        (@targets_waiting)
          && xCAT::DSHCLI->fork_fanout_dsh(
                         $options,          $resolved_targets, \%forked_process,
                         \%pid_targets,     \%outfh_targets,   \%errfh_targets,
                         \@targets_waiting, \%targets_active
                         );

    }

    $dsh_exec_state++;

    if ($$options{'stats'})
    {
        $dsh_stats{'end-time'} = localtime();

        scalar(@targets_finished)
          && ($dsh_stats{'successful-targets'} = \@targets_finished);
        if (scalar(@targets_failed))
        {
            if (@$dsh_target_status{'failed'})
            {
                $dsh_stats{'failed-targets'} = $dsh_target_status{'failed'};
            }
            else
            {
                $dsh_stats{'failed-targets'} = \@targets_failed;
            }
        }
        scalar(@{$dsh_target_status{'canceled'}})
          && ($dsh_stats{'canceled-targets'} = $dsh_target_status{'canceled'});
    }
    my %rsp;
    $rsp->{data}->[0] = "dsh>  Remote_command_execution_completed";
    $$options{'monitor'} && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

    return @targets_failed;
}

#----------------------------------------------------------------------------

=head3
        execute_dshservice

        This is the main driver routine for an instance of the dshservice command.
        Given the options configured in the $options hash table, the routine
        executes the actions specified by the routine

        Arguments:
        	$options - options hash table describing dshservice configuration options

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

sub execute_dshservice
{
    my ($class, $options) = @_;

    if ($$options{'all-valid-contexts'})
    {
        scalar(@dsh_valid_contexts) || xCAT::DSHCLI->get_valid_contexts;

        foreach my $context (sort(@dsh_valid_contexts))
        {
            print STDOUT "$context\n";
        }
    }

    if ($$options{'query'})
    {
        xCAT::DSHCLI->config_default_context($options);

        if (!(-e "$::CONTEXT_DIR$$options{'context'}.pm"))
        {
            my %rsp;
            $rsp->{data}->[0] = " Context: $$options{'context'} not valid.";
            xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);

            return ++$result;
        }

        if ($$options{'nodes'})
        {
            my %resolved_targets   = ();
            my %unresolved_targets = ();
            my %context_targets    = ();
            my @nodenames;

            xCAT::DSHCLI->resolve_targets($options, \%resolved_targets,
                                       \%unresolved_targets, \%context_targets);

            foreach my $user_node (sort keys(%resolved_targets))
            {
                my $properties = $resolved_targets{$user_node};
                my $context    = $$properties{context};
                my $node       = $$properties{hostname};
                $context->query_node($node);
            }
            foreach my $user_node (sort keys(%unresolved_targets))
            {
                my $properties = $unresolved_targets{$user_node};
                my $context    = $$properties{context};
                my $node       = $$properties{hostname};
                $context->query_node($node);
            }

        }
        if ($$options{'defaults'})
        {
            scalar(@dsh_valid_contexts) || xCAT::DSHCLI->get_valid_contexts;

            print STDOUT "DefaultContext=$$options{'context'}\n";

            my $dsh_defaults = xCAT::DSHCLI->get_dsh_defaults;

            foreach my $context (sort keys(%$dsh_defaults))
            {
                my $context_defaults = $$dsh_defaults{$context};
                foreach $key (sort keys(%$context_defaults))
                {
                    my $key_label = $key;
                    ($key eq 'RemoteShell')
                      && ($key_label = 'NodeRemoteShell');
                    print STDOUT
                      "$context:$key_label=$$context_defaults{$key}\n";
                }
            }
        }
    }

    if ($$options{'resolve'})
    {
        my %resolved_targets   = ();
        my %unresolved_targets = ();
        my %context_targets    = ();

        xCAT::DSHCLI->config_default_context($options);

        if (!(-e "$::CONTEXT_DIR$$options{'context'}.pm"))
        {

            my %rsp;
            $rsp->{data}->[0] = " Context: $$options{'context'} not valid.";
            xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
            return ++$result;
        }

        xCAT::DSHCLI->resolve_targets($options, \%resolved_targets,
                                      \%unresolved_targets, \%context_targets);

        my @targets = (sort keys(%resolved_targets));
        push @targets, (sort keys(%unresolved_targets));

        foreach $target (@targets)
        {
            print STDOUT "$target\n";
        }
    }

    if ($$options{'show-config'})
    {
        xCAT::DSHCLI->show_dsh_config($options);
    }

}

#----------------------------------------------------------------------------

=head3
        fork_fanout_dcp

        Main process forking routine for an instance of the dcp command.
        The routine creates forked processes of a remote copy command up to
        the configured fanout value.  Then output from each process is
        processed.  The number of currently forked processes is consistently
        maintained up to the configured fanout value

        Arguments:
			$options - options hash table describing dsh configuration options
        	$resolved_targets - hash table of resolved targets and target properties
        	$forked_process - hash table of process information keyed by target name
        	$pid_targets - hash table of target names keyed by process ID
        	$outfh_targets - hash table of STDOUT pipe handles keyed by target name
        	$errfh_targets - hash table of STDERR pipe handles keyed by target name
        	$targets_waiting - array of targets pending remote execution
        	$targets_active - hash table of currently active targets with output possibly available

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub fork_fanout_dcp
{
    my (
        $class,          $options,         $resolved_targets,
        $forked_process, $pid_targets,     $outfh_targets,
        $errfh_targets,  $targets_waiting, $targets_active
      )
      = @_;

    while (@$targets_waiting
           && (keys(%$targets_active) < $$options{'fanout'}))
    {
        my $user_target       = shift @$targets_waiting;
        my $target_properties = $$resolved_targets{$user_target};

        my @dcp_command;

        if (!$$target_properties{'localhost'})
        {
            my $target_type = $$target_properties{'type'};

            my %rcp_config = ();

            my $remote_copy;
            my $rsh_extension = 'RSH';

            if ($target_type eq 'node')
            {
                $remote_copy =
                     $$options{'node-rcp'}{$$target_properties{'context'}}
                  || $$target_properties{'remote-copy'};
                ($remote_copy =~ /\/scp$/)   && ($rsh_extension = 'SSH');
                ($remote_copy =~ /\/rsync$/) && ($rsh_extension = 'RSYNC');
                $rcp_config{'options'} =
                  $$options{'node-options'}{$$target_properties{'context'}};
            }

            $rcp_config{'preserve'}  = $$options{'preserve'};
            $rcp_config{'recursive'} = $$options{'recursive'};

            if ($$options{'pull'})
            {
                $rcp_config{'src-user'} = $$target_properties{'user'}
                  || $$options{'user'};
                $rcp_config{'src-host'} = $$target_properties{'hostname'};
                $rcp_config{'src-file'} = $$options{'source'};

                my @target_file = split '/', $$options{'source'};
                $rcp_config{'dest-file'} =
                  "$$options{'target'}/$target_file[$#target_file]._$$target_properties{'hostname'}";

            }

            else
            {
                $rcp_config{'src-file'}  = $$options{'source'};
                $rcp_config{'dest-host'} = $$target_properties{'hostname'};
                $rcp_config{'dest-file'} = $$options{'target'};
                $rcp_config{'dest-user'} = $$target_properties{'user'}
                  || $$options{'user'};
                $rcp_config{'destDir_srcFile'} =
                  $$options{'destDir_srcFile'}{$user_target};
            }

            #eval "require RemoteShell::$rsh_extension";
            eval "require xCAT::$rsh_extension";
            my $remoteshell = "xCAT::$rsh_extension";
            @dcp_command =
              $remoteshell->remote_copy_command(\%rcp_config, $remote_copy);

        }
        else
        {
            if ($$options{'destDir_srcFile'}{$user_target})
            {
                open(RSYNCCMDFILE, "> /tmp/rsync_$user_target")
                  or die "can not open file /tmp/rsync_$user_target";
                my $dest_dir_list = join ' ',
                  keys %{$$options{'destDir_srcFile'}{$user_target}};
                print RSYNCCMDFILE "/bin/mkdir -p $dest_dir_list\n";
                foreach my $dest_dir (
                             keys %{$$options{'destDir_srcFile'}{$user_target}})
                {
                    my @src_file =
                      @{$$options{'destDir_srcFile'}{$user_target}{$dest_dir}
                          {'same_dest_name'}};
                    @src_file = map { $_ if -e $_; } @src_file;
                    my $src_file_list = join ' ', @src_file;
                    if ($src_file_list)
                    {
                        print RSYNCCMDFILE "/bin/cp $src_file_list $dest_dir\n";
                    }
                    my %diff_dest_hash =
                      %{$$options{'destDir_srcFile'}{$user_target}{$dest_dir}
                          {'diff_dest_name'}};
                    foreach my $src_file_diff_dest (keys %diff_dest_hash)
                    {
                        next if !-e $src_file_diff_dest;
                        my $diff_basename =
                          $diff_dest_hash{$src_file_diff_dest};
                        print RSYNCCMDFILE
                          "/bin/cp $src_file_diff_dest $dest_dir/$diff_basename\n";
                    }
                }
                print RSYNCCMDFILE "/bin/rm -f /tmp/rsync_$user_target\n";
                close RSYNCCMDFILE;
                chmod 0755, "/tmp/rsync_$user_target";
                @dcp_command = ('/bin/sh', '-c', "/tmp/rsync_$user_target");
            }
            else
            {
                @dcp_command =
                  ('/bin/cp', '-r', $$options{'source'}, $$options{'target'});
            }
        }

        my %rsp;
        $rsp->{data}->[0] = " TRACE: Executing Command:@dcp_command";
        $dsh_trace
          && (xCAT::MsgUtils->message("I", $rsp, $::CALLBACK));

        my @process_info =
          xCAT::DSHCore->fork_output($user_target, @dcp_command);
        vec($$outfh_targets{'bitmap'}, fileno($process_info[1]), 1) = 1;
        vec($$errfh_targets{'bitmap'}, fileno($process_info[2]), 1) = 1;
        $$outfh_targets{fileno($process_info[1])} = $user_target;
        $$errfh_targets{fileno($process_info[2])} = $user_target;

        $$forked_process{$user_target} = \@process_info;
        $$targets_active{$user_target}++;
        $$pid_targets{$process_info[0]} = $user_target;
    }
}

#----------------------------------------------------------------------------

=head3
        fork_fanout_dsh

        Main process forking routine for an instance of the dsh command.
        The routine creates forked processes of a remote shell command up to
        the configured fanout value.  Then output from each process is
        processed.  The number of currently forked processes is consistently
        maintained up to the configured fanout value

        Arguments:
			$options - options hash table describing dsh configuration options
        	$resolved_targets - hash table of resolved targets and target properties
        	$forked_process - hash table of process information keyed by target name
        	$pid_targets - hash table of target names keyed by process ID
        	$outfh_targets - hash table of STDOUT pipe handles keyed by target name
        	$errfh_targets - hash table of STDERR pipe handles keyed by target name
        	$targets_waiting - array of targets pending remote execution
        	$targets_active - hash table of currently active targets with output possibly available

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub fork_fanout_dsh
{
    my (
        $class,          $options,         $resolved_targets,
        $forked_process, $pid_targets,     $outfh_targets,
        $errfh_targets,  $targets_waiting, $targets_active
      )
      = @_;

    while (@$targets_waiting
           && (keys(%$targets_active) < $$options{'fanout'}))
    {
        my $user_target       = shift @$targets_waiting;
        my $target_properties = $$resolved_targets{$user_target};
        my $localShell        =
          ($$options{'syntax'} eq 'csh') ? '/bin/csh' : '/bin/sh';
        my @dsh_command = ($localShell, '-c');
        $$options{'command'} =~ s/\s*$//;
        $$options{'command'} =~ s/;$//;

        if ($$options{'command'} =~ /\&$/)
        {
            $$options{'post-command'} = "";
            $dsh_cmd_background = 1;
        }

        if ($$options{'environment'})
        {
            push @dsh_command,
              "$$options{'pre-command'} . $$options{'environment'} ; $$options{'command'}$$options{'post-command'}";
        }

        else
        {
            push @dsh_command,
              "$$options{'pre-command'}$$options{'command'}$$options{'post-command'}";
        }

        if ($$target_properties{'localhost'})
        {
            if (my $specified_usr =
                ($$target_properties{'user'} || $$options{'user'}))
            {
                my $current_usr = getlogin();
                if ($specified_usr ne $current_usr)
                {
                    delete $$target_properties{'localhost'};
                }
            }
        }

        if (!$$target_properties{'localhost'})
        {
            @dsh_command = ();

            my $target_type = $$target_properties{'type'};

            my %rsh_config = ();
            $rsh_config{'hostname'} = $$target_properties{'hostname'};
            $rsh_config{'user'}     = $$target_properties{'user'}
              || $$options{'user'};

            my $remote_shell;
            my $rsh_extension = 'RSH';

            if ($target_type eq 'node')
            {
                my $context = $$target_properties{'context'};
                     $remote_shell = $$options{'node-rsh'}{$context}
                  || $$options{'node-rsh'}{'none'}
                  || $$target_properties{'remote-shell'}
                  || $$options{'node-rsh-defaults'}{$context};
                ($remote_shell =~ /\/ssh$/) && ($rsh_extension = 'SSH');
                $rsh_config{'options'} = "-n "
                  . $$options{'node-options'}{$$target_properties{'context'}};
            }

            #eval "require RemoteShell::$rsh_extension";
            eval "require xCAT::$rsh_extension";

            $rsh_config{'command'} = "$$options{'pre-command'}";
            my $tmp_env_file;
            if ($$options{'environment'})
            {

                my %rsp;
                $rsp->{data}->[0] = "TRACE: Environment option specified";
                $dsh_trace && (xCAT::MsgUtils->message("I", $rsp, $::CALLBACK));
                my %env_rcp_config = ();
                $tmp_env_file = POSIX::tmpnam . '.dsh';
                $rsh_config{'command'} .= ". $tmp_env_file ; ";

                $env_rcp_config{'src-file'}  = $$options{'environment'};
                $env_rcp_config{'dest-host'} = $$target_properties{'hostname'};
                $env_rcp_config{'dest-file'} = $tmp_env_file;
                $env_rcp_config{'dest-user'} = $$target_properties{'user'}
                  || $$options{'user'};

                my $env_rcp_command   = undef;
                my $env_rcp_extension = $rsh_extension;

                ($$target_properties{'type'} eq 'node')
                  && ($env_rcp_command = $ENV{'DSH_NODE_RCP'});

                if ($env_rcp_command)
                {
                    ($env_rcp_command =~ /\/rcp$/)
                      && ($env_rcp_extension = 'RSH');
                    ($env_rcp_command =~ /\/scp$/)
                      && ($env_rcp_extension = 'SSH');
                }

                #eval "require RemoteShell::$env_rcp_extension";
                eval "require xCAT::$env_rcp_extension";
                my $rcp             = "xCAT::$env_rcp_extension";
                my @env_rcp_command =
                  $rcp->remote_copy_command(\%env_rcp_config);

                my %rsp;
                $rsp->{data}->[0] =
                  "TRACE:Environment: Exporting File.@env_rcp_command ";
                $dsh_trace && (xCAT::MsgUtils->message("I", $rsp, $::CALLBACK));

                my @env_rcp_process =
                  xCAT::DSHCore->fork_no_output($user_target, @env_rcp_command);
                waitpid($env_rcp_process[0], undef);
            }
            my $tmp_cmd_file;
            if ($$options{'execute'})
            {

                my %rsp;
                $rsp->{data}->[0] = "TRACE: Execute option specified.";
                $dsh_trace && (xCAT::MsgUtils->message("I", $rsp, $::CALLBACK));

                my %exe_rcp_config = ();
                $tmp_cmd_file = POSIX::tmpnam . ".dsh";

                my ($exe_cmd, @args) = @{$$options{'execute'}};
                my $chmod_cmd = "";
                $rsh_config{'command'} .=
                  "$chmod_cmd $tmp_cmd_file @args$$options{'post-command'}";
                $exe_rcp_config{'src-file'}  = $exe_cmd;
                $exe_rcp_config{'dest-host'} = $$target_properties{'hostname'};
                $exe_rcp_config{'dest-file'} = $tmp_cmd_file;
                $exe_rcp_config{'dest-user'} = $$target_properties{'user'}
                  || $$options{'user'};

                my $exe_rcp_command   = undef;
                my $exe_rcp_extension = $rsh_extension;

                ($$target_properties{'type'} eq 'node')
                  && ($exe_rcp_command = $ENV{'DSH_NODE_RCP'});

                if ($exe_rcp_command)
                {
                    ($exe_rcp_command =~ /\/rcp$/)
                      && ($exe_rcp_extension = 'RSH');
                    ($exe_rcp_command =~ /\/scp$/)
                      && ($exe_rcp_extension = 'SSH');
                }

                #eval "require RemoteShell::$exe_rcp_extension";
                eval "require xCAT::$exe_rcp_extension";
                my $rcp             = "xCAT::$exe_rcp_extension";
                my @exe_rcp_command =
                  $rcp->remote_copy_command(\%exe_rcp_config);

                my %rsp;
                $rsp->{data}->[0] =
                  "TRACE:Execute: Exporting File:@exe_rcp_command";
                $dsh_trace && (xCAT::MsgUtils->message("I", $rsp, $::CALLBACK));
                my @exe_rcp_process =
                  xCAT::DSHCore->fork_no_output($user_target, @exe_rcp_command);
                waitpid($exe_rcp_process[0], undef);
            }

            else
            {
                $rsh_config{'command'} .=
                  "$$options{'command'}$$options{'post-command'}";
            }
            if ($$options{'environment'})
            {
                $rsh_config{'command'} .= ";rm $tmp_env_file";
            }
            if ($$options{'execute'})
            {
                $rsh_config{'command'} .= ";rm $tmp_cmd_file";
            }

            #eval "require RemoteShell::$rsh_extension";
            eval "require xCAT::$rsh_extension";
            my $remoteshell = "xCAT::$rsh_extension";
            push @dsh_command,
              $remoteshell->remote_shell_command(\%rsh_config, $remote_shell);

        }

        my @process_info;

        my %rsp;
        $rsp->{data}->[0] = "Command name: @dsh_command";
        $dsh_trace && (xCAT::MsgUtils->message("I", $rsp, $::CALLBACK));

        my %rsp;
        $rsp->{data}->[0] = "dsh>  Remote_command_started $user_target";
        $$options{'monitor'} && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

        @process_info = xCAT::DSHCore->fork_output($user_target, @dsh_command);
        if ($process_info[0] == -2)
        {
            my %rsp;
            $rsp->{data}->[0] =
              "$user_target could not execute this command $dsh_command[0] - $$options{'command'} ,  $! ";
            xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
        }

        ($process_info[0] == -3) && (&handle_signal_dsh('INT', 1));

        if ($process_info[0] == -4)
        {

            my %rsp;
            $rsp->{data}->[0] = "Cannot redirect STDOUT, error= $!";
            xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
        }

        if ($process_info[0] == -5)
        {

            my %rsp;
            $rsp->{data}->[0] = "Cannot redirect STDERR, error= $!";
            xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
        }

        vec($$outfh_targets{'bitmap'}, fileno($process_info[1]), 1) = 1;
        vec($$errfh_targets{'bitmap'}, fileno($process_info[2]), 1) = 1;
        $$outfh_targets{fileno($process_info[1])} = $user_target;
        $$errfh_targets{fileno($process_info[2])} = $user_target;

        $$forked_process{$user_target} = \@process_info;
        $$targets_active{$user_target}++;
        $$pid_targets{$process_info[0]} = $user_target;
    }
}

#----------------------------------------------------------------------------

=head3
        buffer_output

        For a given list of targets with output available, this routine buffers
        output from the targets STDOUT pipe handles into buffers grouped by
        target name

        Arguments:
			$options - options hash table describing dsh configuration options
        	$resolved_targets - hash table of resolved targets and target properties
        	$targets_active - hash table of currently active targets with output possibly available
        	$targets_finished - list of targets with all output processed and have completed execution
        	$targets_failed - list of targets that have unsuccessfully executed
        	$targets_buffered - hash table of buffers with output from active targets
        	$pid_targets - hash table of target names keyed by process ID
        	$forked_process - hash table of process information keyed by target name
        	$errfh_targets - hash table of STDERR pipe handles keyed by target name
        	$output_buffers - hash table of STDOUT buffers keyed by target name
        	$error_buffers - hash table of STDERR buffers keyed by target name
			$output_files - list of output file handles where output is to be written
			$error_files - list of error file handles where error output is to be written
			$select_err_fhs - list of currently available STDERR pipe handles

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub buffer_output
{
    my (
        $class,            $options,          $resolved_targets,
        $targets_active,   $targets_finished, $targets_failed,
        $targets_buffered, $pid_targets,      $forked_process,
        $outfh_targets,    $output_buffers,   $error_buffers,
        $output_files,     $error_files,      $select_out_fhs
      )
      = @_;

    foreach $select_out_fh (@$select_out_fhs)
    {

        my $user_target       = $$outfh_targets{$select_out_fh};
        my $output_fh         = $$forked_process{$user_target}[1];
        my $error_fh          = $$forked_process{$user_target}[2];
        my $target_properties = $$resolved_targets{$user_target};

        if (!$$output_buffers{$user_target})
        {
            my @buffer = ();
            $$output_buffers{$user_target} = \@buffer;
        }

        if (!$$output_buffers{"${user_target}_tmp"})
        {
            my @buffer_tmp = ();
            $$output_buffers{"${user_target}_tmp"} = \@buffer_tmp;
        }

        my $eof_output =
          xCAT::DSHCore->pipe_handler_buffer(
                                         $target_properties, $output_fh, 4096,
                                         "$user_target: ",
                                         $$output_buffers{"${user_target}_tmp"},
                                         $$output_buffers{$user_target}
                                         );

        if ($eof_output)
        {
            vec($$outfh_targets{'bitmap'}, fileno($output_fh), 1) = 0;
            delete $$outfh_targets{$user_target};

            if (++$$targets_active{$user_target} == 3)

            {
                my $exit_code;
                my $pid = waitpid($$forked_process{$user_target}[0], 0);
                if ($pid == -1)
                {    # no child waiting ignore
                    my %rsp;
                    $rsp->{data}->[0] = "waitpid call PID=$pid. Ignore.";
                    $$options{'monitor'}
                      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
                }
                else
                {    # check return code
                    $exit_code = $? >> 8;
                }
                if (scalar(@{$$output_buffers{$user_target}}) == 1)
                {
                    ($$output_buffers{$user_target}[0] eq '')
                      && (@{$$output_buffers{$user_target}} = ());
                }

                if (scalar(@{$$error_buffers{$user_target}}) == 1)
                {
                    ($$error_buffers{$user_target}[0] eq '')
                      && (@{$$error_buffers{$user_target}} = ());
                }

                my %exit_status = (
                                 'exit-code' => $exit_code,
                                 'target-rc' => $$target_properties{'target-rc'}
                                 );
                $$targets_buffered{$user_target} = \%exit_status;

                delete $$targets_active{$user_target};
                delete $$pid_targets{$forked_process{$user_target[0]}};

                close $output_fh;
                close $error_fh;
            }
        }
    }
}

#----------------------------------------------------------------------------

=head3
        buffer_error

        For a given list of targets with output available, this routine buffers
        output from the targets STDERR pipe handles into buffers grouped by
        target name

        Arguments:
            $options - options hash table describing dsh configuration options
        	$resolved_targets - hash table of resolved targets and target properties
        	$targets_active - hash table of currently active targets with output possibly available
        	$targets_finished - list of targets with all output processed and have completed execution
        	$targets_failed - list of targets that have unsuccessfully executed
        	$targets_buffered - hash table of buffers with output from active targets
        	$pid_targets - hash table of target names keyed by process ID
        	$forked_process - hash table of process information keyed by target name
        	$errfh_targets - hash table of STDERR pipe handles keyed by target name
        	$output_buffers - hash table of STDOUT buffers keyed by target name
        	$error_buffers - hash table of STDERR buffers keyed by target name
			$output_files - list of output file handles where output is to be written
			$error_files - list of error file handles where error output is to be written
			$select_err_fhs - list of currently available STDERR pipe handles

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub buffer_error
{
    my (
        $class,            $options,          $resolved_targets,
        $targets_active,   $targets_finished, $targets_failed,
        $targets_buffered, $pid_targets,      $forked_process,
        $errfh_targets,    $output_buffers,   $error_buffers,
        $output_files,     $error_files,      $select_err_fhs
      )
      = @_;

    foreach $select_err_fh (@$select_err_fhs)
    {

        my $user_target       = $$errfh_targets{$select_err_fh};
        my $output_fh         = $$forked_process{$user_target}[1];
        my $error_fh          = $$forked_process{$user_target}[2];
        my $target_properties = $$resolved_targets{$user_target};

        if (!$$error_buffers{$user_target})
        {
            my @buffer = ();
            $$error_buffers{$user_target} = \@buffer;
        }

        if (!$$error_buffers{"${user_target}_tmp"})
        {
            my @buffer_tmp = ();
            $$error_buffers{"${user_target}_tmp"} = \@buffer_tmp;
        }

        my $eof_error =
          xCAT::DSHCore->pipe_handler_buffer(
                                          $target_properties, $error_fh, 4096,
                                          "$user_target: ",
                                          $$error_buffers{"${user_target}_tmp"},
                                          $$error_buffers{$user_target}
                                          );

        if ($eof_error)
        {
            vec($$errfh_targets{'bitmap'}, fileno($error_fh), 1) = 0;
            delete $$errfh_targets{$user_target};

            if (++$$targets_active{$user_target} == 3)
            {
                my $exit_code;
                my $pid = waitpid($$forked_process{$user_target}[0], 0);
                if ($pid == -1)
                {    # no child waiting
                    my %rsp;
                    $rsp->{data}->[0] = "waitpid call PID=$pid. Ignore.";
                    $$options{'monitor'}
                      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
                }
                else
                {    # check return code
                    $exit_code = $? >> 8;
                }

                if (scalar(@{$$output_buffers{$user_target}}) == 1)
                {
                    ($$output_buffers{$user_target}[0] eq '')
                      && (@{$$output_buffers{$user_target}} = ());
                }

                if (scalar(@{$$error_buffers{$user_target}}) == 1)
                {
                    ($$error_buffers{$user_target}[0] eq '')
                      && (@{$$error_buffers{$user_target}} = ());
                }

                my %exit_status = (
                                 'exit-code' => $exit_code,
                                 'target-rc' => $$target_properties{'target-rc'}
                                 );
                $$targets_buffered{$user_target} = \%exit_status;

                delete $$targets_active{$user_target};
                delete $$pid_targets{$forked_process{$user_target}[0]};

                close $output_fh;
                close $error_fh;
            }
        }
    }
}

#----------------------------------------------------------------------------

=head3
        stream_output

        For a given list of targets with output available, this routine writes
        output from the targets STDOUT pipe handles directly to STDOUT as soon
        as it is available from the target

        Arguments:
            $options - options hash table describing dsh configuration options
        	$resolved_targets - hash table of resolved targets and target properties
        	$targets_active - hash table of currently active targets with output possibly available
        	$targets_finished - list of targets with all output processed and have completed execution
        	$targets_failed - list of targets that have unsuccessfully executed
        	$targets_buffered - hash table of buffers with output from active targets
        	$pid_targets - hash table of target names keyed by process ID
        	$forked_process - hash table of process information keyed by target name
        	$outfh_targets - hash table of STDOUT pipe handles keyed by target name
        	$output_buffers - hash table of STDOUT buffers keyed by target name
			$output_files - list of error file handles where error output is to be written
			$select_out_fhs - list of currently available STDOUT pipe handles

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub stream_output
{
    my (
        $class,          $options,          $resolved_targets,
        $targets_active, $targets_finished, $targets_failed,
        $pid_targets,    $forked_process,   $outfh_targets,
        $output_buffers, $output_files,     $select_out_fhs
      )
      = @_;

    foreach $select_out_fh (@$select_out_fhs)
    {

        my $user_target       = $$outfh_targets{$select_out_fh};
        my $output_fh         = $$forked_process{$user_target}[1];
        my $target_properties = $$resolved_targets{$user_target};

        if (!$$output_buffers{$user_target})
        {
            my @buffer = ();
            $$output_buffers{$user_target} = \@buffer;
        }

        my $eof_output =
          xCAT::DSHCore->pipe_handler(
                                      $options,
                                      $target_properties,
                                      $output_fh,
                                      4096,
                                      "$user_target: ",
                                      $$output_buffers{$user_target},
                                      @$output_files
                                      );

        if ($eof_output)
        {
            vec($$outfh_targets{'bitmap'}, fileno($output_fh), 1) = 0;
            delete $$outfh_targets{$user_target};

            if (++$$targets_active{$user_target} == 3)
            {
                my $exit_code;
                my $pid = waitpid($$forked_process{$user_target}[0], 0);
                if ($pid == -1)
                {    # no child waiting
                    my %rsp;
                    $rsp->{data}->[0] = "waitpid call PID=$pid. Ignore.";
                    $$options{'monitor'}
                      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
                }
                else
                {    # check return code
                    $exit_code = $? >> 8;
                }

                my $target_rc = $$target_properties{'target-rc'};

                if ($exit_code != 0)
                {
                    my %rsp;
                    $rsp->{data}->[0] =
                      "$user_target remote shell had error code: $exit_code";
                    !$$options{'silent'}
                      && (xCAT::MsgUtils->message("E", $rsp, $::CALLBACK));

                    my %rsp;
                    $rsp->{data}->[0] =
                      "dsh>  Remote_command_failed $user_target";
                    $$options{'monitor'}
                      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                    push @$targets_failed, $user_target;
                    push @{$dsh_target_status{'failed'}}, $user_target
                      if !$signal_interrupt_flag;

                }

                else
                {
                    if ($target_rc != 0)
                    {

                        my %rsp;
                        $rsp->{data}->[0] =
                          " $user_target remote Command had return code: $$target_properties{'target-rc'} ";
                        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);

                        my %rsp;
                        $rsp->{data}->[0] =
                          "dsh>  Remote_command_failed $user_target";
                        $$options{'monitor'}
                          && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                        push @$targets_failed, $user_target;
                    }

                    elsif (!defined($target_rc))
                    {

                        my %rsp;
                        $rsp->{data}->[0] =
                          " $user_target a return code run on this host was not received. ";
                        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);

                        my %rsp;
                        $rsp->{data}->[0] =
                          "dsh>  Remote_command_failed $user_target";
                        $$options{'monitor'}
                          && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                        push @$targets_failed, $user_target;
                    }

                    else
                    {

                        my %rsp;
                        $rsp->{data}->[0] =
                          "dsh>  Remote_command_successful $user_target";
                        $$options{'monitor'}
                          && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                        push @$targets_finished, $user_target;
                    }
                }

                delete $$targets_active{$user_target};
                delete $$pid_targets{$$forked_process{$user_target}[0]};
            }

            close $output_fh;
        }
    }
}

#----------------------------------------------------------------------------

=head3
        stream_error

        For a given list of targets with output available, this routine writes
        output from the targets STDERR pipe handles directly to STDERR as soon
        as it is available from the target

        Arguments:
            $options - options hash table describing dsh configuration options
        	$resolved_targets - hash table of resolved targets and target properties
        	$targets_active - hash table of currently active targets with output possibly available
        	$targets_finished - list of targets with all output processed and have completed execution
        	$targets_failed - list of targets that have unsuccessfully executed
        	$targets_buffered - hash table of buffers with output from active targets
        	$pid_targets - hash table of target names keyed by process ID
        	$forked_process - hash table of process information keyed by target name
        	$errfh_targets - hash table of STDERR pipe handles keyed by target name
        	$error_buffers - hash table of STDERR buffers keyed by target name
			$error_files - list of error file handles where error output is to be written
			$select_err_fhs - list of currently available STDERR pipe handles

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub stream_error
{
    my (
        $class,          $options,          $resolved_targets,
        $targets_active, $targets_finished, $targets_failed,
        $pid_targets,    $forked_process,   $errfh_targets,
        $error_buffers,  $error_files,      $select_err_fhs
      )
      = @_;

    foreach $select_err_fh (@$select_err_fhs)
    {

        my $user_target       = $$errfh_targets{$select_err_fh};
        my $error_fh          = $$forked_process{$user_target}[2];
        my $target_properties = $$resolved_targets{$user_target};

        if (!$$error_buffers{$user_target})
        {
            my @buffer = ();
            $$error_buffers{$user_target} = \@buffer;
        }

        my $eof_error =
          xCAT::DSHCore->pipe_handler(
                                      $options,
                                      $target_properties,
                                      $error_fh,
                                      4096,
                                      "$user_target: ",
                                      $error_buffers{$user_target},
                                      @$error_files
                                      );

        if ($eof_error)
        {
            vec($$errfh_targets{'bitmap'}, fileno($error_fh), 1) = 0;
            delete $$errfh_targets{$user_target};

            if (++$$targets_active{$user_target} == 3)
            {
                my $exit_code;
                my $pid = waitpid($$forked_process{$user_target}[0], 0);
                if ($pid == -1)
                {    # no child waiting
                    my %rsp;
                    $rsp->{data}->[0] = "waitpid call PID=$pid. Ignore.";
                    $$options{'monitor'}
                      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
                }
                else
                {    # check return code
                    $exit_code = $? >> 8;
                }

                my $target_rc = $$target_properties{'target-rc'};

                if ($exit_code != 0)
                {
                    my %rsp;
                    $rsp->{data}->[0] =
                      " $user_target remote shell had exit code $exit_code.";
                    !$$options{'silent'}
                      && (xCAT::MsgUtils->message("E", $rsp, $::CALLBACK));

                    my %rsp;
                    $rsp->{data}->[0] =
                      "dsh>  Remote_command_failed $user_target";
                    $$options{'monitor'}
                      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                    push @$targets_failed, $user_target;
                    push @{$dsh_target_status{'failed'}}, $user_target
                      if !$signal_interrupt_flag;

                }

                else
                {
                    if ($target_rc != 0)
                    {

                        my %rsp;
                        rsp->{data}->[0] =
                          "$user_target remote command had return code $$target_properties{'target-rc'}";
                        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);

                        my %rsp;
                        $rsp->{data}->[0] =
                          "dsh>  Remote_command_failed $user_target";
                        $$options{'monitor'}
                          && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                        push @$targets_failed, $user_target;
                    }

                    elsif (!defined($target_rc))
                    {

                        my %rsp;
                        $rsp->{data}->[0] =
                          "A return code for the command run on $user_target was not received.";
                        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);

                        my %rsp;
                        $rsp->{data}->[0] =
                          "dsh>  Remote_command_failed $user_target";
                        $$options{'monitor'}
                          && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                        push @$targets_failed, $user_target;
                    }

                    else
                    {

                        my %rsp;
                        $rsp->{data}->[0] =
                          "dsh>  Remote_command_successful $user_target";
                        $$options{'monitor'}
                          && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                        push @$targets_finished, $user_target;
                    }
                }

                delete $$targets_active{$user_target};
                delete $$pid_targets{$$forked_process{$user_target}[0]};
            }

            close $error_fh;
        }
    }
}

#----------------------------------------------------------------------------

=head3
        config_default_context

        Return the name of the default context to the caller

        Arguments:
			$options - options hash table describing dsh configuration options

        Returns:
        	The name of the default context

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub config_default_context
{
    my ($class, $options) = @_;

    if (!$$options{'context'})
    {
        my $contextdir = $::CONTEXT_DIR;
        $contextdir .= "XCAT.pm";
        if (-e "$contextdir")
        {
            require Context::XCAT;
            (XCAT->valid_context) && ($$options{'context'} = 'XCAT');
        }

        $$options{'context'} = $ENV{'DSH_CONTEXT'}
          || $$options{'context'}
          || 'DSH';
    }
}

#----------------------------------------------------------------------------

=head3
        config_dcp

        This routine configures the command environment for an instance of the
        dcp command based on the configuration of the DSH Utilities environment
        defined in $options.

        Arguments:
            $options - options hash table describing dsh configuration options

        Returns:
        	Number of configuration errors

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub config_dcp
{
    my ($class, $options) = @_;

    my $result = 0;

    $$options{'trace'} && $dsh_trace++;

    $dsh_trace && xCAT::DSHCLI->show_dsh_config($options);

    xCAT::DSHCLI->config_default_context($options);

    if (!(-e "$::CONTEXT_DIR$$options{'context'}.pm"))
    {

        my %rsp;
        $rsp->{data}->[0] = "Invalid context specified:$$options{'context'}.";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
        return ++$result;
    }

    my %rsp;
    $rsp->{data}->[0] = "TRACE:Default context is $$options{'context'}.";
    $dsh_trace
      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

    !$$options{'node-rcp'}
      && (   $$options{'node-rcp'} = $ENV{'DCP_NODE_RCP'}
          || $ENV{'DCP_COPY_CMD'}
          || undef);

    if ($$options{'node-rcp'})
    {
        my %node_rcp        = ();
        my @remotecopy_list = split ',', $$options{'node-rcp'};

        foreach $context_remotecopy (@remotecopy_list)
        {
            my ($context, $remotecopy) = split ':', $context_remotecopy;

            if (!$remotecopy)
            {
                $remotecopy = $context;
                scalar(@dsh_valid_contexts) || xCAT::DSHCLI->get_valid_contexts;

                foreach $context (@dsh_valid_contexts)
                {
                    !$node_rcp{$context}
                      && ($node_rcp{$context} = $remotecopy);
                }
            }

            else
            {
                $node_rcp{$context} = $remotecopy;
            }
        }

        $$options{'node-rcp'} = \%node_rcp;
    }

    $$options{'fanout'} = $$options{'fanout'} || $ENV{'DSH_FANOUT'} || 64;

    my %rsp;
    $rsp->{data}->[0] = "TRACE:Fanout Value is $$options{'fanout'}.";
    $dsh_trace
      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

    $$options{'timeout'} = $$options{'timeout'} || $ENV{'DSH_TIMEOUT'} || undef;

    my %rsp;
    $rsp->{data}->[0] = "TRACE:Timeout Value is $$options{'timeout'}.";
    $dsh_trace
      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

    if (   (!$$options{'nodes'})
        && ($ENV{'DSH_NODE_LIST'} || $ENV{'DSH_LIST'}))
    {
        require Context::DSH;

        my $node_list_file = $ENV{'DSH_NODE_LIST'}
          || $ENV{'DSH_LIST'}
          || $ENV{'WCOLL'};
        my $node_list = DSH->read_target_file($node_list_file);
        $$options{'nodes'} = join ',', @$node_list;
    }

    elsif (!$$options{'nodes'} && $ENV{'DSH_NODE_LIST'})
    {
        require Context::DSH;

        my $node_list_file = $ENV{'DSH_NODE_LIST'};
        my $node_list      = DSH->read_target_file($node_list_file);
        $$options{'nodes'} = join ',', @$node_list;
    }

    $$options{'node-options'} = $$options{'node-options'}
      || $ENV{'DCP_NODE_OPTS'}
      || $ENV{'DSH_REMOTE_OPTS'};

    if ($$options{'node-options'})
    {
        my %node_options    = ();
        my @remoteopts_list = split ',', $$options{'node-options'};

        foreach $context_remoteopts (@remoteopts_list)
        {
            my ($context, $remoteopts) = split ':', $context_remoteopts;

            if (!$remoteopts)
            {
                $remoteopts = $context;
                scalar(@dsh_valid_contexts) || xCAT::DSHCLI->get_valid_contexts;

                foreach $context (@dsh_valid_contexts)
                {
                    !$node_options{$context}
                      && ($node_options{$context} = $remoteopts);
                }
            }

            else
            {
                $node_options{$context} = $remoteopts;
            }
        }

        $$options{'node-options'} = \%node_options;
    }

    if ($$options{'pull'} && !(-d $$options{'target'}))
    {
        my %rsp;
        $rsp->{data}->[0] =
          "Cannot copy to target $$options{'target'}. Directory does not exist.";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
        return ++$result;
    }

    return 0;
}

#----------------------------------------------------------------------------

=head3
        config_dsh

        This routine configures the command environment for an instance of the
        dsh command based on the configuration of the DSH Utilities environment
        defined in $options.

        Arguments:
            $options - options hash table describing dsh configuration options

        Returns:
        	Number of configuration errors

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub config_dsh
{
    my ($class, $options) = @_;

    my $result = 0;

    $$options{'stats'} = $$options{'monitor'};

    if ($$options{'stats'})
    {
        $dsh_stats{'start-time'} = localtime();

        $dsh_stats{'user'} = $$options{'user'} || `whoami`;
        chomp($dsh_stats{'user'});
        $dsh_stats{'successful-targets'}     = ();
        $dsh_stats{'failed-targets'}         = ();
        $dsh_stats{'report-status-messages'} = ();
        $dsh_stats{'specified-targets'}      = ();
        scalar(@dsh_valid_contexts) || xCAT::DSHCLI->get_valid_contexts;
        push @{$dsh_stats{'valid-contexts'}}, @dsh_valid_contexts;

        foreach $context (@dsh_valid_contexts)
        {
            $dsh_stats{'specified-targets'}{$context} = ();
            $dsh_stats{'specified-targets'}{$context}{'nodes'} = ();
        }

        $$options{'command-name'} = $$options{'command-name'} || 'Unspecified';
        $$options{'command-description'} = $$options{'command-description'}
          || '';

    }

    $$options{'trace'} && $dsh_trace++;

    $dsh_trace && xCAT::DSHCLI->show_dsh_config;

    xCAT::DSHCLI->config_default_context($options);
    my $test = " $::CONTEXT_DIR$$options{'context'}.pm";
    if (!(-e "$::CONTEXT_DIR$$options{'context'}.pm"))
    {

        my %rsp;
        $rsp->{data}->[0] = "Invalid context specified: $$options{'context'}";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
        return ++$result;
    }

    my %rsp;
    $rsp->{data}->[0] = "TRACE:Default context is $$options{'context'}";
    $dsh_trace
      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

    !$$options{'node-rsh'}
      && (   $$options{'node-rsh'} = $ENV{'DSH_NODE_RSH'}
          || $ENV{'DSH_REMOTE_CMD'}
          || undef);

    my %rsp;
    $rsp->{data}->[0] = "TRACE:Node RSH is $$options{'node-rsh'}";
    $dsh_trace
      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

    my %node_rsh_defaults = ();

    scalar(@dsh_valid_contexts) || xCAT::DSHCLI->get_valid_contexts;

    foreach $context (@dsh_valid_contexts)
    {
        eval "require Context::$context";
        my $defaults = $context->context_defaults;
        $node_rsh_defaults{$context} = $$defaults{'NodeRemoteShell'}
          || $$defaults{'RemoteShell'};
    }

    $$options{'node-rsh-defaults'} = \%node_rsh_defaults;

    my %node_rsh = ();

    if ($$options{'node-rsh'})
    {

        my @remoteshell_list = split ',', $$options{'node-rsh'};

        foreach $context_remoteshell (@remoteshell_list)
        {
            my ($context, $remoteshell) = split ':', $context_remoteshell;

            if (!$remoteshell)
            {
                $remoteshell = $context;
                !$node_rsh{'none'} && ($node_rsh{'none'} = $remoteshell);
            }

            else
            {
                !$node_rsh{$context} && ($node_rsh{$context} = $remoteshell);
            }
        }
    }

    $$options{'node-rsh'} = \%node_rsh;

    $$options{'environment'} = $$options{'environment'}
      || $ENV{'DSH_ENVIRONMENT'}
      || undef;

    if ($$options{'environment'} && (-z $$options{'environment'}))
    {
        my %rsp;
        $rsp->{data}->[0] = "File: $$options{'environment'} is empty.";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
        $$options{'environment'} = undef;
    }

    $$options{'fanout'} = $$options{'fanout'} || $ENV{'DSH_FANOUT'} || 64;

    my %rsp;
    $rsp->{data}->[0] = "TRACE: Fanout value is $$options{'fanout'}.";
    $dsh_trace
      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

    $$options{'syntax'} = $$options{'syntax'} || $ENV{'DSH_SYNTAX'} || undef;

    if (
        defined($$options{'syntax'})
        && (   ($$options{'syntax'} ne 'csh')
            && ($$options{'syntax'} ne 'ksh'))
      )
    {
        my %rsp;
        $rsp->{data}->[0] =
          "Incorrect argument \"$$options{'syntax'}\" specified on -S flag. ";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
        return ++$result;
    }

    my $env_set    = 'export';
    my $env_assign = '=';

    if ($$options{'syntax'} eq 'csh')
    {
        $env_set    = 'setenv';
        $env_assign = ' ';
    }

    my $path_set;
    $ENV{'DSH_PATH'}
      && ($path_set = "$env_set PATH$env_assign$ENV{'DSH_PATH'};");

    $$options{'timeout'} = $$options{'timeout'} || $ENV{'DSH_TIMEOUT'} || undef;

    my %rsp;
    $rsp->{data}->[0] = "TRACE: Timeout value is $$options{'timeout'} ";
    $dsh_trace
      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

    # Set a default PATH
    $$options{'pre-command'} = $path_set;

    if (!$$options{'no-locale'})
    {
        my @output = `/usr/bin/locale`;
        chomp(@output);

        my @settings = ();
        !($$options{'syntax'} eq 'csh') && (push @settings, $env_set);

        foreach $line (@output)
        {
            $line =~ s/=/$env_assign/;

            if ($$options{'syntax'} eq 'csh')
            {
                push @settings, "$env_set $line;";
            }

            else
            {
                push @settings, $line;
            }
        }

        if ($$options{'syntax'} eq 'csh')
        {
            push @settings, "$env_set PERL_BADLANG${env_assign}0;";
        }

        else
        {
            push @settings, "PERL_BADLANG${env_assign}0";
        }

        my $locale_settings = join ' ', @settings;
        !($$options{'syntax'} eq 'csh') && ($locale_settings .= ' ; ');

        $$options{'pre-command'} .= $locale_settings;
    }

    if ($$options{'syntax'} eq 'csh')
    {
        $$options{'post-command'} =
          "; $env_set DSH_TARGET_RC$env_assign\$status; echo \":DSH_TARGET_RC=\${DSH_TARGET_RC}:\"";
    }

    else
    {
        $$options{'post-command'} =
          "; $env_set DSH_TARGET_RC$env_assign\$?; echo \":DSH_TARGET_RC=\${DSH_TARGET_RC}:\"";
    }

    $$options{'exit-status'}
      && ($$options{'post-command'} .=
          ' ; echo "Remote_command_rc = $DSH_TARGET_RC"');

    if (
        !$$options{'nodes'}
        && (   $ENV{'DSH_NODE_LIST'}
            || $ENV{'DSH_LIST'})
      )
    {
        require Context::DSH;

        my $node_list_file = $ENV{'DSH_NODE_LIST'}
          || $ENV{'DSH_LIST'}
          || $ENV{'WCOLL'};
        my $node_list = DSH->read_target_file($node_list_file);
        $$options{'nodes'} = join ',', @$node_list;
    }

    elsif (!$$options{'nodes'} && $ENV{'DSH_NODE_LIST'})
    {
        require Context::DSH;

        my $node_list_file = $ENV{'DSH_NODE_LIST'};
        my $node_list      = DSH->read_target_file($node_list_file);
        $$options{'nodes'} = join ',', @$node_list;
    }

    $$options{'node-options'} = $$options{'node-options'}
      || $ENV{'DSH_NODE_OPTS'}
      || $ENV{'DSH_REMOTE_OPTS'};

    if ($$options{'node-options'})
    {
        my %node_options    = ();
        my @remoteopts_list = split ',', $$options{'node-options'};

        foreach $context_remoteopts (@remoteopts_list)
        {
            my ($context, $remoteopts) = split ':', $context_remoteopts;

            if (!$remoteopts)
            {
                $remoteopts = $context;
                scalar(@dsh_valid_contexts) || xCAT::DSHCLI->get_valid_contexts;

                foreach $context (@dsh_valid_contexts)
                {
                    !$node_options{$context}
                      && ($node_options{$context} = $remoteopts);
                }
            }

            else
            {
                $node_options{$context} = $remoteopts;
            }
        }

        $$options{'node-options'} = \%node_options;
    }

    if ($$options{'execute'})
    {
        my @exe_command = split ' ', $$options{'command'};
        $$options{'execute'} = \@exe_command;

        if (!(-e $exe_command[0]))
        {

            my %rsp;
            $rsp->{data}->[0] = "File $exe_command[0] does not exist";
            xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
            return ++$result;
        }

        if (-z $exe_command[0])
        {

            my %rsp;
            $rsp->{data}->[0] = "File $exe_command[0] is empty.";
            xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
            return ++$result;
        }

        if (!(-x $exe_command[0]))
        {

            my %rsp;
            $rsp->{data}->[0] = "File $exe_command[0] is not executable.";
            xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
            return ++$result;
        }
    }

    return 0;
}

#----------------------------------------------------------------------------

=head3
        config_signals_dsh

        Configures the signal handling routines for each system signal
        and configures which signals should be restored as define in the
        DSH environment options.

        Arguments:
        	$options - options hash table describing dsh configuration options

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub config_signals_dsh
{
    my ($class, $options) = @_;

    $SIG{'STOP'} = 'DEFAULT';
    $SIG{'CONT'} = 'DEFAULT';
    $SIG{'TSTP'} = 'DEFAULT';

    $SIG{'TERM'} = 'xCAT::DSHCLI::handle_signal_dsh';
    $SIG{'QUIT'} = 'xCAT::DSHCLI::handle_signal_dsh';
    $SIG{'INT'}  = 'xCAT::DSHCLI::handle_signal_dsh';
    $SIG{'ABRT'} = 'xCAT::DSHCLI::handle_signal_dsh';
    $SIG{'ALRM'} = 'xCAT::DSHCLI::handle_signal_dsh';
    $SIG{'FPE'}  = 'xCAT::DSHCLI::handle_signal_dsh';
    $SIG{'ILL'}  = 'xCAT::DSHCLI::handle_signal_dsh';
    $SIG{'PIPE'} = 'xCAT::DSHCLI::handle_signal_dsh';
    $SIG{'SEGV'} = 'xCAT::DSHCLI::handle_signal_dsh';
    $SIG{'USR1'} = 'xCAT::DSHCLI::handle_signal_dsh';
    $SIG{'USR2'} = 'xCAT::DSHCLI::handle_signal_dsh';
    $SIG{'TTIN'} = 'xCAT::DSHCLI::handle_signal_dsh';
    $SIG{'TTOU'} = 'xCAT::DSHCLI::handle_signal_dsh';
    $SIG{'BUS'}  = 'xCAT::DSHCLI::handle_signal_dsh';

    my @ignore_signals = split /,/, $$options{'ignore-signal'};

    foreach $signal (@ignore_signals)
    {

        if (   ($signal ne 'STOP')
            && ($signal ne 'CONT')
            && ($signal ne 'TSTP'))
        {

            $SIG{$signal} = 'IGNORE';
        }

    }
}

#----------------------------------------------------------------------------

=head3
        handle_signal_dsh

        Signal handling routine for an instance of the dsh command.  Depending
        on the state of dsh execution and report configuraion, this routine
        properly writes reports and output files if a termination signal is recieved

        Arguments:
        	$signal - termination signal to handle
        	$fatal - 1 if signal is fatal, 0 otherwise

        Returns:
        	None

        Globals:
        	$dsh_execution_state - current state of dsh execution

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub handle_signal_dsh
{
    my ($signal, $fatal_error) = @_;

    my $DSH_STATE_BEGIN                   = 0;
    my $DSH_STATE_INIT_STARTED            = 1;
    my $DSH_STATE_INIT_COMPLETE           = 2;
    my $DSH_STATE_TARGET_RESOLVE_COMPLETE = 3;
    my $DSH_STATE_REMOTE_EXEC_STARTED     = 4;
    my $DSH_STATE_REMOTE_EXEC_COMPLETE    = 5;

    if ($dsh_exec_state == $DSH_STATE_BEGIN)
    {
        my %rsp;
        $rsp->{data}->[0] =
          "Command execution ended prematurely due to a previous error or stop request from the user.";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
        exit(1);
    }

    elsif ($dsh_exec_state == $DSH_STATE_INIT_STARTED)
    {
        my %rsp;
        $rsp->{data}->[0] =
          "Command execution ended prematurely due to a previous error or stop request from the user.";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);

        exit(1);
    }

    elsif ($dsh_exec_state == $DSH_STATE_INIT_COMPLETE)
    {
        if ($$dsh_options{'stats'})
        {
            $dsh_stats{'exec-state'} = $dsh_exec_state;
            $dsh_stats{'end-time'}   = localtime();
        }

        if (@{$dsh_target_status{'waiting'}})
        {
            foreach $user_target (@{$dsh_target_status{'waiting'}})
            {
                if ($fatal_error)
                {

                    my %rsp;
                    $rsp->{data}->[0] =
                      "Running the command on $user_target has been cancelled due to unrecoverable error.  The command was never sent to the host.";
                    xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
                }

                else
                {

                    my %rsp;
                    $rsp->{data}->[0] =
                      "dsh>  Remote_command_cancelled $user_target";
                    $$dsh_options{'monitor'}
                      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
                }

                push @{$dsh_target_status{'canceled'}}, $user_target;
            }
        }

        my %rsp;
        $rsp->{data}->[0] =
          "Running the command on $user_target has been cancelled due to unrecoverable error or stop request by user.\nNo commands were executed on any host.";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);

        if ($$dsh_options{'stats'})
        {
            my @empty_targets = ();

            $dsh_stats{'successful-targets'} = \@empty_targets;
            $dsh_stats{'failed-targets'}     = \@empty_targets;
            $dsh_stats{'canceled-targets'}   = $dsh_target_status{'canceled'};
        }

        my %rsp;
        $rsp->{data}->[0] = "dsh>  Dsh_remote_execution_completed.";
        $$dsh_options{'monitor'}
          && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

        exit(1);

    }

    elsif ($dsh_exec_state == $DSH_STATE_TARGET_RESOLVE_COMPLETE)
    {
        if ($$dsh_options{'stats'})
        {
            $dsh_stats{'exec-state'} = $dsh_exec_state;
            $dsh_stats{'end-time'}   = localtime();
        }

        if (@{$dsh_target_status{'waiting'}})
        {
            foreach $user_target (@{$dsh_target_status{'waiting'}})
            {
                if ($fatal_error)
                {

                    my %rsp;
                    $rsp->{data}->[0] =
                      "$user_target: running of the command on this host has been cancelled due to unrecoverable error.\n The command was never sent to the host.";
                    xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
                }

                else
                {

                    my %rsp;
                    $rsp->{data}->[0] =
                      "$user_target: running of the command on this host has been cancelled due to unrecoverable error or stop request by user.\n The command was never sent to the host.";
                    xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                    my %rsp;
                    $rsp->{data}->[0] =
                      "dsh>  Remote_command_cancelled $user_target";
                    $$dsh_options{'monitor'}
                      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
                }

                push @{$dsh_target_status{'canceled'}}, $user_target;
            }
        }

        @{$dsh_target_status{'waiting'}} = ();

        my %rsp;
        $rsp->{data}->[0] =
          "Command execution ended prematurely due to a previous unrecoverable error or stop by user.\n No commands were executed on any host.";

        if ($$dsh_options{'stats'})
        {
            my @empty_targets = ();

            $dsh_stats{'successful-targets'} = \@empty_targets;
            $dsh_stats{'failed-targets'}     = \@empty_targets;
            $dsh_stats{'canceled-targets'}   = $dsh_target_status{'canceled'};
        }

        my %rsp;
        $rsp->{data}->[0] = "dsh>  Dsh_remote_execution_completed";
        $$options{'monitor'} && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

        exit(1);
    }

    elsif ($dsh_exec_state == $DSH_STATE_REMOTE_EXEC_STARTED)
    {
        if ($$dsh_options{'stats'})
        {
            $dsh_stats{'exec-state'} = $dsh_exec_state;
            $dsh_stats{'end-time'}   = localtime();
        }

        my $targets_active      = $dsh_target_status{'active'};
        my @targets_active_list = keys(%$targets_active);

        if (@targets_active_list)
        {
            my %rsp;
            $rsp->{data}->[0] =
              "Caught SIG$signal - terminating the child processes.";
            !$$dsh_options{'stats'}
              && xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);

            my $target_signal = $signal;
            my $last_error    = $!;

            if ($signal ne 'QUIT' && $signal ne 'INT' && $signal ne 'TERM')
            {
                $target_signal = 'TERM';
                $SIG{'TERM'} = 'IGNORE';
            }

            $SIG{$signal} = 'DEFAULT';

            foreach $user_target (@targets_active_list)
            {
                if ($$dsh_options{'stats'})
                {
                    if ($fatal_error)
                    {

                        my %rsp;
                        $rsp->{data}->[0] =
                          "Running the command on $user_target has been interrupted due to unrecoverable error.  The command may not have completed successfully.";
                        xCAT::MsgUtils->message("V", $rsp, $::CALLBACK);
                    }

                    else
                    {

                        my %rsp;
                        $rsp->{data}->[0] =
                          "Running the command on $user_target has been interrupted due to unrecoverable error or stop request by the user.  The command may not have completed successfully.";
                        xCAT::MsgUtils->message("V", $rsp, $::CALLBACK);
                    }
                }

                my $target_pid = $$dsh_forked_process{$user_target}[0];
                kill $target_signal, $target_pid;
                push @{$dsh_target_status{'failed'}}, $user_target;
                $signal_interrupt_flag = 1;
            }

            $! = $last_error;
        }

        if (@{$dsh_target_status{'waiting'}})
        {
            foreach $user_target (@{$dsh_target_status{'waiting'}})
            {
                if ($fatal_error)
                {

                    my %rsp;
                    $rsp->{data}->[0] =
                      "Running the command on $user_target has been cancelled due to unrecoverable error.  The command was never sent to the host.";
                    xCAT::MsgUtils->message("V", $rsp, $::CALLBACK);
                }

                else
                {

                    my %rsp;
                    $rsp->{data}->[0] =
                      "Running the command on $user_target has been cancelled due to unrecoverable error or stop request by the user.  The command was never sent to the host.";
                    xCAT::MsgUtils->message("V", $rsp, $::CALLBACK);

                    my %rsp;
                    $rsp->{data}->[0] =
                      "dsh>  Remote_command_cancelled $user_target";
                    $$dsh_options{'monitor'}
                      && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
                }

                push @{$dsh_target_status{'canceled'}}, $user_target;
            }
        }

        @{$dsh_target_status{'waiting'}} = ();

        my %rsp;
        $rsp->{data}->[0] =
          "Command execution ended prematurely due to a previous unrecoverable error or stop request by the user.";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);

        if ($$dsh_options{'stats'})
        {
            my @empty_targets = ();

            $dsh_stats{'successful-targets'} = $dsh_target_status{'finished'};
            $dsh_stats{'failed-targets'}     = $dsh_target_status{'failed'};
            $dsh_stats{'canceled-targets'}   = $dsh_target_status{'canceled'};
        }

        return;
    }

    elsif ($dsh_exec_state == $DSH_STATE_REMOTE_EXEC_COMPLETE)
    {
        if ($$dsh_options{'stats'})
        {
            $dsh_stats{'exec-state'} = $dsh_exec_state;
            $dsh_stats{'end-time'}   = localtime();
        }

        my %rsp;
        $rsp->{data}->[0] =
          "Running the command  stopped due to unrecoverable error or stop request by the user.";
        xCAT::MsgUtils->message("V", $rsp, $::CALLBACK);

        return;
    }

    else
    {
        my %rsp;
        $rsp->{data}->[0] =
          "Running the command  stopped due to unrecoverable error or stop request by the user.";
        xCAT::MsgUtils->message("V", $rsp, $::CALLBACK);
        exit(1);
    }
}

#----------------------------------------------------------------------------

=head3
        resolve_targets

        Main target resolution routine.  This routine calls calls all appropriate
        target resolution routines to resolve target information in the
        dsh command environment.  Currently the routine delegates resolution to
        resolve_nodes.

        Arguments:
        	$options - options hash table describing dsh configuration options
        	$resolved_targets - hash table of resolved targets and target properties
        	$unresolved_targets - hash table of unresolved targets and target properties
        	$context_targets - hash table of targets grouped by context name

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub resolve_targets
{
    my ($class, $options, $resolved_targets, $unresolved_targets,
        $context_targets)
      = @_;

    $$options{'nodes'}
      && xCAT::DSHCLI->resolve_nodes($options,            $resolved_targets,
                                     $unresolved_targets, $context_targets);
}

#----------------------------------------------------------------------------

=head3
        resolve_nodes

        For a given list of contexts and node names, build a list of
        nodes defined and augment the list with context node information.

        Arguments:
        	$options - options hash table describing dsh configuration options
        	$resolved_targets - hash table of resolved targets and target properties
        	$unresolved_targets - hash table of unresolved targets and target properties
        	$context_targets - hash table of targets grouped by context name

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub resolve_nodes
{
    my ($class, $options, $resolved_targets, $unresolved_targets,
        $context_targets)
      = @_;
    
    my @node_list = ();
    @node_list = split ',' , $$options{'nodes'};

    foreach $context_node (@node_list)
    {
        my ($context, $node) = split ':', $context_node;
        !$node
          && (($node = $context) && ($context = $$options{'context'}));

        push @{$dsh_stats{'specified-targets'}{$context}{'nodes'}}, $node;
    }

    xCAT::DSHCLI->_resolve_nodes($options, $resolved_targets,
                                 $unresolved_targets, $context_targets,
                                 @node_list);
}

#----------------------------------------------------------------------------

=head3
        _resolve_nodes

        Wrapper routine for resolve_all_nodes, resolve_nodes and


        Arguments:
            $options - options hash table describing dsh configuration options
        	$resolved_targets - hash table of resolved targets and target properties
        	$unresolved_targets - hash table of unresolved targets and relevant properties
			$context_targets - hash table of targets grouped by context name
			@nodes - a list of nodes to resolve

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub _resolve_nodes
{

    my ($class, $options, $resolved_targets, $unresolved_targets,
        $context_targets, @nodes)
      = @_;

    my %resolved_nodes   = ();
    my %unresolved_nodes = ();
    xCAT::DSHCore->resolve_hostnames($options, \%resolved_nodes,
                                     \%unresolved_nodes, $context_targets,
                                     @nodes);
    xCAT::DSHCore->removeExclude(\%resolved_nodes, $unresolved_targets,
                                 $context_targets);
    xCAT::DSHCore->removeExclude($resolved_targets, \%unresolved_nodes,
                                 $context_targets);

    foreach $node (keys(%unresolved_nodes))
    {
        my $node_properties = $unresolved_nodes{$node};

        $$node_properties{'type'} = 'node';
        $$unresolved_targets{$node} = $node_properties;

        my %rsp;
        $rsp->{data}->[0] =
          "The specified node $node is not defined to the cluster.";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
    }

    foreach $user_node (keys(%resolved_nodes))
    {
        my $node_properties = $resolved_nodes{$user_node};

        $$node_properties{'type'} = 'node';

        eval "require Context::$$node_properties{'context'}";
        my $result =
          $$node_properties{'context'}->resolve_node($node_properties);

        $result && ($$resolved_targets{$user_node} = $node_properties);
    }
}

#----------------------------------------------------------------------------

=head3
        verify_targets

        Executes a verification test for all targets across all
        available contexts.  If a target cannot be verified it is removed
        from the $resolved_targets list

        Arguments:
        	$options - options hash table describing dsh configuration options
        	$resolved_targets - hash table of resolved targets and target properties

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub verify_targets
{
    my ($class, $options, $resolved_targets) = @_;
    foreach $user_target (keys(%$resolved_targets))
    {
        my $context  = $$resolved_targets{$user_target}{'context'};
        my $hostname = $$resolved_targets{$user_target}{'hostname'};
        eval "require Context::$context";
        my $mode = $context->verify_mode($hostname);
        if (($mode eq "Managed") && ($context->verify_target($hostname) == 1))
        {
            my $target = $context->verify_target();
            my %rsp;
            $rsp->{data}->[0] = "TRACE:Verifying $hostname with $target.";
            $dsh_trace
              && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
        }
        elsif ($mode eq "MinManaged")
        {
            if ($context->verify_target($hostname) == 1)
            {
                my $target = $context->verify_target();
                my %rsp;
                $rsp->{data}->[0] = "TRACE:Verifying $hostname with $target.";
                $dsh_trace
                  && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

            }
            elsif ($context->verify_target($hostname) == 0)
            {
                my %rsp;
                $rsp->{data}->[0] =
                  "$user_target is not responding. No command will be issued to this host.";
                xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);

                my %rsp;
                $rsp->{data}->[0] =
                  "dsh>  Remote_command_cancelled $user_target";
                $$dsh_options{'monitor'}
                  && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                push @{$dsh_target_status{'canceled'}}, $user_target;
                delete $$resolved_targets{$user_target};
            }
            else
            {
                push @ping_list, $hostname;
            }
        }
        else
        {
            push @ping_list, $hostname;
        }
    }

    if (@ping_list)
    {

        my @no_response = ();
        my %rsp;
        $rsp->{data}->[0] =
          "TRACE:Verifying remaining targets with pping command.";
        $dsh_trace && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
        @no_response = xCAT::DSHCore->pping_hostnames(@ping_list);

        foreach $hostname (@no_response)
        {
            my @targets = grep /$hostname/, keys(%$resolved_targets);

            foreach $user_target (@targets)
            {
                my %rsp;
                $rsp->{data}->[0] =
                  "$user_target is not responding. No command will be issued to this host.";
                xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);

                my %rsp;
                $rsp->{data}->[0] =
                  "dsh>  Remote_command_cancelled $user_target";
                $$dsh_options{'monitor'}
                  && xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);

                push @{$dsh_target_status{'canceled'}}, $user_target;
                $$dsh_unresolved_targets{$user_target} =
                  $$resolved_targets{$user_target};
                delete $$resolved_targets{$user_target};
            }
        }
    }
}

#----------------------------------------------------------------------------

=head3
        get_available_contexts

        Returns a list of available contexts in the DSH environment

        Arguments:
        	None

        Returns:
        	A list of available contexts in the DSH environment

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub get_available_contexts
{
    opendir(DIR, $::CONTEXT_DIR);
    my @contexts =
      grep { ($_ ne '.') && ($_ ne '..') && ($_ =~ /\.pm$/) } readdir DIR;
    closedir DIR;

    chomp(@contexts);

    foreach $context (@contexts)
    {
        $context =~ s/\.pm$//;

        push @dsh_available_contexts, $context;
    }
}

#----------------------------------------------------------------------------

=head3
        get_dsh_config

        Get the initial DSH configuration for all available contexts

        Arguments:
        	None

        Returns:
        	A hash table of configuration properties grouped by context

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub get_dsh_config
{
    scalar(@dsh_valid_contexts) || xCAT::DSHCLI->get_valid_contexts;

    my %dsh_config = ();
    foreach $context (@dsh_valid_contexts)
    {
        $dsh_config{$context} = $context->context_properties;
    }

    return \%dsh_config;
}

#----------------------------------------------------------------------------

=head3
        get_dsh_defaults

        Get the default properties for all available contexts

        Arguments:
        	None

        Returns:
        	A hash table of default properties for each context

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------
sub get_dsh_defaults
{
    scalar(@dsh_valid_contexts) || xCAT::DSHCLI->get_valid_contexts;

    my %dsh_defaults = ();
    foreach $context (@dsh_valid_contexts)
    {
        $dsh_defaults{$context} = $context->context_defaults;
    }

    return \%dsh_defaults;
}

#----------------------------------------------------------------------------

=head3
        get_valid_contexts

        Returns a list of valid contexts in the DSH environment.
        A valid context is one that is available in the DSH environment
        and whose valid_context routine returns 1

        Arguments:
        	None

        Returns:
        	A list of valid contexts

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------

sub get_valid_contexts
{
    scalar(@dsh_available_contexts) || xCAT::DSHCLI->get_available_contexts;
    @dsh_valid_contexts = ();

    foreach $context (@dsh_available_contexts)
    {
        eval "require Context::$context";
        ($context->valid_context) && (push @dsh_valid_contexts, $context);
    }
}

#----------------------------------------------------------------------------

=head3
        util_bit_indexes

        Utility routine that converts a bit vector to a corresponding array
        of 1s and 0s

        Arguments:
        	None

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#----------------------------------------------------------------------------

sub util_bit_indexes
{
    my ($class, $vector, $bit) = @_;

    my @bit_indexes = ();
    my @bits        = split(//, unpack("b*", $vector));

    my $index = 0;
    while (@bits)
    {
        ((shift @bits) == $bit) && (push @bit_indexes, $index);
        $index++;
    }

    return @bit_indexes;
}

#-------------------------------------------------------------------------------

=head3
   check_valid_options

    Arguments:
        1 - %options
    Returns:
        1 - there are invalid options
        0 - options are all okay
    Globals:
        none
    Error:
        none
    Comments:
        none

=cut

#--------------------------------------------------------------------------------

sub check_valid_options
{
    my ($pkg, $options) = @_;

    if (scalar(@$options) > 0)
    {
        my @invalid_opts;
        my @valid_longnames = (
                               "continue",           "execute",
                               "fanout",             "help",
                               "user",               "monitor",
                               "nodes",              "node-options",
                               "node-rsh",           "stream",
                               "timeout",            "verify",
                               "exit-status",        "context",
                               "environment",        "ignore-sig",
                               "ignoresig",          "no-locale",
                               "nodegroups",         "silent",
                               "syntax",             "trace",
                               "version",            "command-name",
                               "commandName",        "command-description",
                               "commandDescription", "noFileWriting",
                               "preserve",           "node-rcp",
                               "pull",               "recursive"
                               );

        foreach my $opt (@$options)
        {
            my $tmp_opt = $opt;

            # remove any leading dash first
            $tmp_opt =~ s/^-*//;

            # if this is a long keyword...
            if (grep /^\Q$tmp_opt\E$/, @valid_longnames)
            {

                # there should be two leading dashs
                if ($opt !~ /^--\w+/)
                {
                    push @invalid_opts, $opt;
                }
            }
        }
        if (@invalid_opts)
        {
            my %rsp;
            my $badopts = join(',', @invalid_opts);
            $rsp->{data}->[0] = "Invalid options: $badopts";
            xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
            return 1;
        }
    }
    return 0;
}

#-------------------------------------------------------------------------------

=head3
    ignoreEnv


    Remove dsh environment variable.

    Arguments:
        envList: indicates the env vars that seperated by comma
    Returns:
        None
    Globals:
        @dsh_valie_env
    Error:
        none
    Example:
        if ( defined $options{'ignore_env'} ) { xCAT::DSHCLI->ignoreEnv( $options{'ignore_env'}); }
    Comments:
        none

=cut

#--------------------------------------------------------------------------------

sub ignoreEnv
{
    my ($class, $envList) = @_;
    my @env_not_valid = ();
    my @env_to_save = split ',', $envList;
    for my $env (@env_to_save)
    {
        if (!grep /$env/, @dsh_valid_env)
        {
            push @env_not_valid, $env;
        }
    }
    if (scalar @env_not_valid > 0)
    {
        $env = join ",", @env_not_valid;
        my %rsp;
        $rsp->{data}->[0] = "Invalid Environment Variable: $env";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
        exit 1;
    }
    for my $env (@dsh_valid_env)
    {
        if (!grep /$env/, @env_to_save)
        {
            delete $ENV{$env};
        }
    }
}

#--------------------------------------------------------------------------------

=head3
    isFdNumExceed

    check if file descriptor number exceed the max number in ulimit

    Arguments:
        $node_fd: indicates the file descriptor number required by each nodes
        $node_num: indicates the target nodes number
        $fanout: indicates the fanout value
        $remain_fd: indicates the file descriptor number remained by main processes
    Returns:
        0: file descriptor number does not exceed the max number
        1: file descriptor number exceed the max number
    Globals:
        None
    Error:
        None
    Example:
        xCAT::DSHCLI->check_fd_num(2, scalar( keys(%resolved_targets)), $$options{'fanout'})

    Comments:
        none

=cut

#--------------------------------------------------------------------------------
sub isFdNumExceed
{

    my ($class, $node_fs, $node_num, $fanout) = @_;

    # Check the file descriptor number
    my $ulimit_cmd;
    my $ls_cmd;
    if ($^O =~ /^linux$/i)
    {
        $ulimit_cmd =
          "/bin/bash -c \'ulimit -n\'";    #ulimit is embedded in bash on linux
        $ls_cmd = '/bin/ls';
    }
    else
    {
        $ulimit_cmd = '/usr/bin/ulimit -n';    #On AIX
        $ls_cmd     = '/usr/bin/ls';
    }
    my $fdnum = xCAT::Utils->runcmd($ulimit_cmd);

    return 0 if ($fdnum =~ /\s*unlimited\s*/);

    if ($fdnum !~ /\s*\d+\s*/)                 #this should never happen
    {
        my %rsp;
        $rsp->{data}->[0] = "Unsupport ulimit return code!";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
        exit 1;
    }

    my $pid = getpid;

    #    print "pid is $pid\n";

    #there are some pid will be remained by dsh main process, such STDIN, STDOUT and others,
    #it can be different on different system. So need to check them everytime
    my @remain_fds    = xCAT::Utils->runcmd($ls_cmd . " /proc/$pid/fd");
    my $remain_fd_num = scalar(@remain_fds);

    #    print "remain fd num is $remain_fd_num\n";
    #   sleep 1000;
    $node_num = ($node_num < $fanout) ? $node_num : $fanout;
    my $max_fd_req = $node_fs * $node_num;  #the max fd number required by nodes

    if (($max_fd_req + $remain_fd_num) > $fdnum)
    {
        return 1;
    }
    else
    {
        return 0;
    }
}

#-------------------------------------------------------------------------------

=head3
      usage_dsh

        puts out dsh usage message

        Arguments:
          None

        Returns:

        Globals:


        Error:
        	None


=cut

#-------------------------------------------------------------------------------

sub usage_dsh
{
## usage message

    my $usagemsg1 =
      " xdsh -h \n xdsh -q \n xdsh -v \n xdsh [noderange] [group]\n";
    my $usagemsg2 =
      "      [-B bypass ] [-C context] [-c] [-e] [-E environment_file] [-f fanout]\n";
    my $usagemsg3 = "      [-l user_ID] [-L] [-K ssh setup] ";
    my $usagemsg4 = "[-m] [-o options][-q] [-Q] [-r remote_shell] \n";
    my $usagemsg5 =
      "      [-s] [-S ksh | csh] [-t timeout] [-T] [-X environment variables] [-v] [-z]\n";
    my $usagemsg6 = "      [command_list]\n";
    my $usagemsg7 =
      "Note:Context always defaults to XCAT unless -C flag is set.";
    my $usagemsg .= $usagemsg1 .= $usagemsg2 .= $usagemsg3 .= $usagemsg4 .=
      $usagemsg5 .= $usagemsg6 .= $usagemsg7;
###  end usage mesage
    if ($::CALLBACK)
    {
        my %rsp;
        $rsp->{data}->[0] = $usagemsg;
        xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
    }
    else
    {
        xCAT::MsgUtils->message("I", $usagemsg . "\n");
    }
    return;
}

#-------------------------------------------------------------------------------

=head3
       parse_and_run_dsh

        This parses the dsh input build the call to execute_dsh.

        Arguments:
		  $nodes,$args,$callback,$command,$noderange
		  These may exist, called from xdsh plugin

        Returns:
           Errors if invalid options or the executed dsh command

        Globals:


        Error:
        	None

        Example:

        Comments:

=cut

#-------------------------------------------------------------------------------

sub parse_and_run_dsh
{
    my ($class, $nodes, $args, $callback, $command, $noderange) = @_;

    @ARGV       = @{$args};    # get arguments
    $::CALLBACK = $callback;
    if ($ENV{'XCATROOT'})
    {
        $::XCATROOT = $ENV{'XCATROOT'};    # setup xcatroot home directory
    }
    elsif (-d '/opt/xcat')
    {
        $::XCATROOT = "/opt/xcat";
    }
    else
    {
        $::XCATROOT = "/usr";
    }

    # parse the arguments
    Getopt::Long::Configure("posix_default");
    Getopt::Long::Configure("no_gnu_compat");
    Getopt::Long::Configure("bundling");

    my %options = ();

    # check for wrong long options
    if (xCAT::DSHCLI->check_valid_options(\@ARGV))
    {
        usage_dsh;
        exit 1;
    }

    if (
        !GetOptions(
            'e|execute'        => \$options{'execute'},
            'f|fanout=i'       => \$options{'fanout'},
            'h|help'           => \$options{'help'},
            'l|user=s'         => \$options{'user'},
            'm|monitor'        => \$options{'monitor'},
            'o|node-options=s' => \$options{'node-options'},
            'q|show-config'    => \$options{'show-config'},
            'r|node-rsh=s'     => \$options{'node-rsh'},
            's|stream'         => \$options{'streaming'},
            't|timeout=i'      => \$options{'timeout'},
            'v|verify'         => \$options{'verify'},
            'z|exit-status'    => \$options{'exit-status'},

            'B|bypass'                 => \$options{'bypass'},
            'C|context=s'              => \$options{'context'},
            'E|environment=s'          => \$options{'environment'},
            'I|ignore-sig|ignoresig=s' => \$options{'ignore-signal'},
            'K|keysetup'               => \$options{'ssh-setup'},
            'L|no-locale'              => \$options{'no-locale'},
            'Q|silent'                 => \$options{'silent'},
            'S|syntax=s'               => \$options{'syntax'},
            'T|trace'                  => \$options{'trace'},
            'V|version'                => \$options{'version'},

            'command-name|commandName=s' => \$options{'command-name'},
            'command-description|commandDescription=s' =>
              \$options{'command-description'},
            'X:s' => \$options{'ignore_env'}

        )
      )
    {
        usage_dsh;
        exit 1;
    }

    if ($options{'help'})
    {
        usage_dsh;
        exit 0;
    }

    if ($options{'show-config'})
    {
        xCAT::DSHCLI->show_dsh_config;
        exit 0;
    }
    if ($options{'node-rsh'}
        && (!-f $options{'node-rsh'} || !-x $options{'node-rsh'}))
    {
        my %rsp;
        $rsp->{data}->[0] =
          "Remote command: $options{'node-rcp'} does not exist or is not executable";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
        exit 1;
    }

    if (defined $options{'ignore_env'})
    {
        xCAT::DSHCLI->ignoreEnv($options{'ignore_env'});
    }

    #
    # build list of nodes
    my @nodelist = @$nodes;
    $options{'nodes'} = join(',', @nodelist);

    # build arguments

    $options{'command'} = join ' ', @ARGV;

    # -K option just sets up the ssh keys on the nodes and exits
    if (defined $options{'ssh-setup'})
    {
        my $rc      = xCAT::Utils->setupSSH($noderange);
        my @results = "return code = $rc";
        return (@results);
    }
    if (!(@ARGV))
    {    #  no args , an error
        my %rsp;
        $rsp->{data}->[0] = "No command argument provided";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK, 1);
        return;
    }

    #
    # Execute the dsh api
    my @results = xCAT::DSHCLI->runDsh_api(\%options, 0);
    if ($::RUNCMD_RC)
    {    # error from dsh
        my %rsp;
        $rsp->{data}->[0] = "Error from dsh. Return Code = $::RUNCMD_RC";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK, 1);

    }
    return (@results);
}

#-------------------------------------------------------------------------------

=head3
      usage_dcp

        puts out dcp usage message

        Arguments:
          None

        Returns:

        Globals:


        Error:
        	None


=cut

#-------------------------------------------------------------------------------

sub usage_dcp
{
    ### usage message
    my $usagemsg1 = " xdcp -h \n xdcp \n xdcp -v \n xdcp [noderange] [group]\n";
    my $usagemsg2 =
      "      [-B bypass] [-C context] [-c] [-f fanout] [-l user_ID]\n";
    my $usagemsg3 =
      "      [-o options] [-s] [-p] [-P] [-q] [-Q] [-r node_remote_copy]\n";
    my $usagemsg4 =
      "      [-R] [-t timeout] [-T] [-X environment variables] [-v] \n";
    my $usagemsg5 = "      source_file... target_path\n";
    my $usagemsg6 =
      "Note:Context is always defaults to XCAT unless the -C flag is input.";
    my $usagemsg .= $usagemsg1 .= $usagemsg2 .= $usagemsg3 .= $usagemsg4 .=
      $usagemsg5 .= $usagemsg6;

    if ($::CALLBACK)
    {
        my %rsp;
        $rsp->{data}->[0] = $usagemsg;
        xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
    }
    else
    {
        xCAT::MsgUtils->message("I", $usagemsg . "\n");
    }
    return;
}

#-------------------------------------------------------------------------------

=head3
       parse_and_run_dcp

        This parses the dcp input build the call to execute_dcp.

        Arguments:
		  $nodes,$args,$callback,$command,$noderange
		  These may exist, called from xdsh plugin

        Returns:
           Errors if invalid options or the executed dcp command

        Globals:


        Error:
        	None

        Example:

        Comments:

=cut

#-------------------------------------------------------------------------------

sub parse_and_run_dcp
{
    my ($class, $nodes, $args, $callback, $command, $noderange) = @_;
    @ARGV       = @{$args};    # get arguments
    $::CALLBACK = $callback;
    if ($ENV{'XCATROOT'})
    {
        $::XCATROOT = $ENV{'XCATROOT'};    # setup xcatroot home directory
    }
    else
    {
        $::XCATROOT = "/opt/xcat";
    }

    # parse the arguments
    Getopt::Long::Configure("posix_default");
    Getopt::Long::Configure("no_gnu_compat");
    Getopt::Long::Configure("bundling");

    my %options = ();

    # check for wrong long options
    if (xCAT::DSHCLI->check_valid_options(\@ARGV))
    {
        usage_dcp;
        exit 1;
    }
    if (
        !GetOptions(
                    'f|fanout=i'       => \$options{'fanout'},
                    'h|help'           => \$options{'help'},
                    'l|user=s'         => \$options{'user'},
                    'o|node-options=s' => \$options{'node-options'},
                    'q|show-config'    => \$options{'show-config'},
                    'p|preserve'       => \$options{'preserve'},
                    'r|c|node-rcp=s'   => \$options{'node-rcp'},
                    's'                => \$options{'rsync'},
                    't|timeout=i'      => \$options{'timeout'},
                    'v|verify'         => \$options{'verify'},
                    'B|bypass'         => \$options{'bypass'},
                    'C|context=s'      => \$options{'context'},
                    'Q|silent'         => \$options{'silent'},
                    'P|pull'           => \$options{'pull'},
                    'R|recursive'      => \$options{'recursive'},
                    'T|trace'          => \$options{'trace'},
                    'V|version'        => \$options{'version'},
                    'X:s'              => \$options{'ignore_env'}
        )
      )
    {
        usage_dcp;
        exit(1);
    }

    if ($options{'help'})
    {
        usage_dcp;
        exit(0);
    }
    if ($options{'show-config'})
    {
        xCAT::DSHCLI->show_dsh_config;
        exit 0;
    }

    if ($options{'version'})
    {
        my %rsp;
        $rsp->{data}->[0] = "Version 2.0";
        xCAT::MsgUtils->message("I", $rsp, $::CALLBACK);
        exit(0);
    }

    if (defined $options{'ignore_env'})
    {
        xCAT::DSHCLI->ignoreEnv($options{'ignore_env'});
    }

    # rsync chosen and node-rcp path not input, then use rsync
    ($options{'rsync'} && !$options{'node-rcp'})
      && ($options{'node-rcp'} = '/usr/bin/rsync');

    if ($options{'node-rcp'}
        && (!-f $options{'node-rcp'} || !-x $options{'node-rcp'}))
    {
        my %rsp;
        $rsp->{data}->[0] =
          "Remote command: $options{'node-rcp'} does not exist or is not executable";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK, 1);
        exit;
    }

    if ($ENV{'DSH_COPY_FILE_LIST'})
    {
        &parse_input_file(\%options, $ENV{'DSH_COPY_FILE_LIST'});
    }
    else
    {
        if (@ARGV < 1)
        {
            my %rsp;
            $rsp->{data}->[0] = "Missing file arguments";
            xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
            $rsp->{data}->[0] = $usagemsg;
            xCAT::MsgUtils->message("I", $rsp, $::CALLBACK, 1);
            exit;
        }

        elsif (@ARGV == 1)
        {
            if ($options{'pull'})
            {
                my %rsp;
                $rsp->{data}->[0] = "Missing target_path";
                xCAT::MsgUtils->message("E", $rsp, $::CALLBACK);
                $rsp->{data}->[0] = $usagemsg;
                xCAT::MsgUtils->message("I", $rsp, $::CALLBACK, 1);
                exit;
            }

            else
            {
                $options{'target'} = '';
                $options{'source'} = pop @ARGV;
            }
        }

        elsif ($options{'pull'} && (@ARGV > 2))
        {
            my %rsp;
            $rsp->{data}->[0] =
              "Cannot pull more than one file from targets.";
            xCAT::MsgUtils->message("I", $rsp, $::CALLBACK, 1);
            exit;
        }

        else
        {
            $options{'target'} = pop @ARGV;
            $options{'source'} = join $::__DCP_DELIM, @ARGV;
        }
    }

    #
    # build list of nodes
    my @nodelist = @$nodes;
    $options{'nodes'} = join(',', @nodelist);

    # Execute the dcp api
    my @results = xCAT::DSHCLI->runDcp_api(\%options, 0);
    if ($::RUNCMD_RC)
    {    # error from dcp
        my %rsp;
        $rsp->{data}->[0] = "Error from dsh. Return Code = $::RUNCMD_RC";
        xCAT::MsgUtils->message("E", $rsp, $::CALLBACK, 1);

    }
    return (@results);

}

#-------------------------------------------------------------------------------

=head3
       parse_input_file

        This parses the dcp input build the call to execute_dcp.

        Arguments:
		  $nodes,$args,$callback,$command,$noderange
		  These may exist, called from xdsh plugin

        Returns:
           Errors if invalid options or the executed dcp command

        Globals:


        Error:
        	None

        Example:

        Comments:

=cut

#-------------------------------------------------------------------------------

sub parse_input_file
{
    use File::Basename;
    my ($options, $input_file) = @_;
    open(INPUTFILE, "< $input_file") || die "File $input_file does not exist\n";
    while (my $line = <INPUTFILE>)
    {
        chomp $line;
        if ($line =~ /(.+) -> \((.+)\) install (.+)/)
        {
            my $src_file      = $1;
            my $host_list     = $2;
            my $dest_file     = $3;
            my $src_basename  = basename($src_file);
            my $dest_basename = basename($dest_file);
            $dest_basename =~ s/[\s;]//g;
            my @dest_host = split ' ', $host_list;
            my $dest_dir  = dirname($dest_file);

            foreach my $target_node (@dest_host)
            {
                $$options{'destDir_srcFile'}{$target_node}            ||= {};
                $$options{'destDir_srcFile'}{$target_node}{$dest_dir} ||= {};
                if ($src_basename eq $dest_basename)
                {
                    $$options{'destDir_srcFile'}{$target_node}{$dest_dir}
                      {'same_dest_name'} ||= [];
                    push @{$$options{'destDir_srcFile'}{$target_node}{$dest_dir}
                          {'same_dest_name'}}, $src_file;
                }
                else
                {
                    $$options{'destDir_srcFile'}{$target_node}{$dest_dir}
                      {'diff_dest_name'} ||= {};
                    $$options{'destDir_srcFile'}{$target_node}{$dest_dir}
                      {'diff_dest_name'}{$src_file} = $dest_basename;
                }
            }
        }
    }
    close INPUTFILE;
    $$options{'nodes'} = join ',', keys %{$$options{'destDir_srcFile'}};
}

#-------------------------------------------------------------------------------

=head3
      runDsh_api

  This subroutine provides a concise interface to run remote command on multiple nodes.
  Arguments:
      $optionRef:
         Specifies a hash in which the dsh options are provided
      $exitCode:
        Normally, if there is an error running the cmd,
		it will display the error msg
        and exit with the cmds exit code, unless exitcode is given one of the
        following values:
             0:     display error msg, DO NOT exit on error, but set
                $::RUNCMD_RC to the exit code.
            -1:     DO NOT display error msg and DO NOT exit on error, but set
	                   $::RUNCMD_RC to the exit code.
            -2:    DO the default behavior (display error msg and exit with cmds
                exit code.
        number > 0:    Display error msg and exit with the given code
        $refoutput:
          if refoutput is true, then the output will be returned as a
		  reference to an array for efficiency.
  Example:
      my @outref = xCAT::DSHCLI->runDsh_api(\%options, -2);


=cut

#-------------------------------------------------------------------------------

sub runDsh_api
{
    shift;
    my ($optionsRef, $exitCode, $refoutput) = @_;

    $::DSH_API         = 1;
    $::DSH_API_MESSAGE = "";
    my $verbose_old = $::VERBOSE;
    $::VERBOSE   = 0;
    $::RUNCMD_RC = xCAT::DSHCLI->execute_dsh($optionsRef);
    $::DSH_API   = 0;
    $::VERBOSE   = $verbose_old;
    my $returnCode;    #command will exit with this code
    if ($::RUNCMD_RC)
    {
        my $dsh_api_displayerr = 1;
        if (defined($exitCode) && length($exitCode) && $exitCode != -2)
        {
            if ($exitCode > 0)
            {
                $returnCode = $exitCode;
            }
            elsif ($exitCode <= 0)
            {
                $returnCode = '';
                if ($exitCode < 0)
                {
                    $dsh_api_displayerr = 0;
                }
            }
        }
        else
        {
            $returnCode = $::RUNCMD_RC;
        }
        if ($dsh_api_displayerr)
        {
            my $errmsg = '';
            if (xCAT::Utils->isLinux() && $::RUNCMD_RC == 139)
            {
                $errmsg = "Segmentation fault  $errmsg";
            }
            else
            {
                $errmsg = $::DSH_API_MESSAGE;
            }
            if (!$DSHCLI::NO_MESSAGES)
            {
                xCAT::MsgUtils->message(
                    "E",
                    "dsh command: $$optionsRef{'command'} failed on  nodes:$::DSH_API_NODES_FAILED\n"
                    );
            }
        }

    }

    if ($refoutput)
    {
        my $outputRef = [];
        @$outputRef = split "\n", $::DSH_API_MESSAGE;
        chomp @$outputRef;
        return $outputRef;
    }
    elsif (wantarray)
    {
        my @outputLines = split "\n", $::DSH_API_MESSAGE;
        chomp @outputLines;
        return @outputLines;
    }
    else
    {
        return $::DSH_API_MESSAGE;
    }
}

#-------------------------------------------------------------------------------

=head3
  runDcp_api

    This subroutine provides a concise interface to run remote command
	on multiple nodes.
    Arguments:
           $optionRef:
               Specifies a hash in which the dsh options are provided
           $exitCode:
              Normally, if there is an error running the cmd,
			  it will display the error msg
              and exit with the cmds exit code,
			  unless exitcode is given one of the
              following values:
                       0:     display error msg, DO NOT exit on error, but set
                              $::RUNCMD_RC to the exit code.
                      -1:     DO NOT display error msg
							  and DO NOT exit on error, but set
                              $::RUNCMD_RC to the exit code.
                      -2:    DO the default behavior
							 (display error msg and exit with cmds
                             exit code.
              number > 0:    Display error msg and exit with the
							 given code
              $refoutput:
                             if refoutput is true, then the output
							 will be returned as a reference to
                             an array for efficiency.
     Example:
            my @outref = xCAT::DSHCLI->runDcp_api(\%options, -2);

=cut

#-------------------------------------------------------------------------------

sub runDcp_api
{
    shift;
    my ($optionsRef, $exitCode, $refoutput) = @_;

    $::DCP_API         = 1;
    $::DCP_API_MESSAGE = "";
    my $verbose_old = $::VERBOSE;
    $::VERBOSE = 0;
    if (!ref($optionsRef->{'source'}))
    {
        $optionsRef->{'source'} =~ s/\s/$::__DCP_DELIM/g;
    }
    elsif (ref($optionsRef->{'source'} eq "ARRAY"))
    {
        $optionsRef->{'source'} = join $::__DCP_DELIM,
          @{$optionsRef->{'source'}};
    }

    $::RUNCMD_RC = xCAT::DSHCLI->execute_dcp($optionsRef);
    $::DCP_API   = 0;
    $::VERBOSE   = $verbose_old;
    my $returnCode;    #command will exit with this code
    if ($::RUNCMD_RC)
    {
        my $dcp_api_displayerr = 1;
        if (defined($exitCode) && length($exitCode) && $exitCode != -2)
        {
            if ($exitCode > 0)
            {
                $returnCode = $exitCode;
            }
            elsif ($exitCode <= 0)
            {
                $returnCode = '';
                if ($exitCode < 0)
                {
                    $dcp_api_displayerr = 0;
                }
            }
        }
        else
        {
            $returnCode = $::RUNCMD_RC;
        }
        if ($dcp_api_displayerr)
        {
            my $errmsg = '';
            if (xCAT::Utils->isLinux() && $::RUNCMD_RC == 139)
            {
                $errmsg = "Segmentation fault  $errmsg";
            }
            else
            {
                $errmsg = $::DCP_API_MESSAGE;
            }
            if (!$DSHCLI::NO_MESSAGES)
            {
                xCAT::MsgUtils->message("E",
                              "dcp command failed, Return code=$::RUNCMD_RC\n");
            }
        }

    }
    if ($refoutput)
    {
        my $outputRef = [];
        @$outputRef = split "\n", $::DCP_API_MESSAGE;
        chomp @$outputRef;
        return $outputRef;
    }
    elsif (wantarray)
    {
        my @outputLines = split "\n", $::DCP_API_MESSAGE;
        chomp @outputLines;
        return @outputLines;
    }
    else
    {
        return $::DCP_API_MESSAGE;
    }
}

#-------------------------------------------------------------------------------

=head3
        show_dsh_config

        Displays the current configuration of the dsh command environment
        and configuration information for each installed context

        Arguments:
        	$options - options hash table describing dsh configuration options

        Returns:
        	None

        Globals:
        	None

        Error:
        	None

        Example:

        Comments:

=cut

#-------------------------------------------------------------------------------
sub show_dsh_config
{
    my ($class, $options) = @_;
    xCAT::DSHCLI->config_default_context($options);

    my $dsh_config = xCAT::DSHCLI->get_dsh_config;

    foreach my $context (sort keys(%$dsh_config))
    {
        my $context_properties = $$dsh_config{$context};
        foreach $key (sort keys(%$context_properties))
        {
            print STDOUT "$context:$key=$$context_properties{$key}\n";

        }
    }
}

1;