#!/usr/bin/env perl

# This program is part of Percona Toolkit: http://www.percona.com/software/
# See "COPYRIGHT, LICENSE, AND WARRANTY" at the end of this file for legal
# notices and disclaimers.

use strict;
use warnings FATAL => 'all';
use constant MKDEBUG => $ENV{MKDEBUG} || 0;

# ###########################################################################
# OptionParser package
# This package is a copy without comments from the original.  The original
# with comments and its test file can be found in the Bazaar repository at,
#   lib/OptionParser.pm
#   t/lib/OptionParser.t
# See https://launchpad.net/percona-toolkit for more information.
# ###########################################################################
{
package OptionParser;

use strict;
use warnings FATAL => 'all';
use English qw(-no_match_vars);
use constant MKDEBUG => $ENV{MKDEBUG} || 0;

use List::Util qw(max);
use Getopt::Long;

my $POD_link_re = '[LC]<"?([^">]+)"?>';

sub new {
   my ( $class, %args ) = @_;
   my @required_args = qw();
   foreach my $arg ( @required_args ) {
      die "I need a $arg argument" unless $args{$arg};
   }

   my ($program_name) = $PROGRAM_NAME =~ m/([.A-Za-z-]+)$/;
   $program_name ||= $PROGRAM_NAME;
   my $home = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';

   my %attributes = (
      'type'       => 1,
      'short form' => 1,
      'group'      => 1,
      'default'    => 1,
      'cumulative' => 1,
      'negatable'  => 1,
   );

   my $self = {
      head1             => 'OPTIONS',        # These args are used internally
      skip_rules        => 0,                # to instantiate another Option-
      item              => '--(.*)',         # Parser obj that parses the
      attributes        => \%attributes,     # DSN OPTIONS section.  Tools
      parse_attributes  => \&_parse_attribs, # don't tinker with these args.

      %args,

      strict            => 1,  # disabled by a special rule
      program_name      => $program_name,
      opts              => {},
      got_opts          => 0,
      short_opts        => {},
      defaults          => {},
      groups            => {},
      allowed_groups    => {},
      errors            => [],
      rules             => [],  # desc of rules for --help
      mutex             => [],  # rule: opts are mutually exclusive
      atleast1          => [],  # rule: at least one opt is required
      disables          => {},  # rule: opt disables other opts 
      defaults_to       => {},  # rule: opt defaults to value of other opt
      DSNParser         => undef,
      default_files     => [
         "/etc/percona-toolkit/percona-toolkit.conf",
         "/etc/percona-toolkit/$program_name.conf",
         "$home/.percona-toolkit.conf",
         "$home/.$program_name.conf",
      ],
      types             => {
         string => 's', # standard Getopt type
         int    => 'i', # standard Getopt type
         float  => 'f', # standard Getopt type
         Hash   => 'H', # hash, formed from a comma-separated list
         hash   => 'h', # hash as above, but only if a value is given
         Array  => 'A', # array, similar to Hash
         array  => 'a', # array, similar to hash
         DSN    => 'd', # DSN
         size   => 'z', # size with kMG suffix (powers of 2^10)
         time   => 'm', # time, with an optional suffix of s/h/m/d
      },
   };

   return bless $self, $class;
}

sub get_specs {
   my ( $self, $file ) = @_;
   $file ||= $self->{file} || __FILE__;
   my @specs = $self->_pod_to_specs($file);
   $self->_parse_specs(@specs);

   open my $fh, "<", $file or die "Cannot open $file: $OS_ERROR";
   my $contents = do { local $/ = undef; <$fh> };
   close $fh;
   if ( $contents =~ m/^=head1 DSN OPTIONS/m ) {
      MKDEBUG && _d('Parsing DSN OPTIONS');
      my $dsn_attribs = {
         dsn  => 1,
         copy => 1,
      };
      my $parse_dsn_attribs = sub {
         my ( $self, $option, $attribs ) = @_;
         map {
            my $val = $attribs->{$_};
            if ( $val ) {
               $val    = $val eq 'yes' ? 1
                       : $val eq 'no'  ? 0
                       :                 $val;
               $attribs->{$_} = $val;
            }
         } keys %$attribs;
         return {
            key => $option,
            %$attribs,
         };
      };
      my $dsn_o = new OptionParser(
         description       => 'DSN OPTIONS',
         head1             => 'DSN OPTIONS',
         dsn               => 0,         # XXX don't infinitely recurse!
         item              => '\* (.)',  # key opts are a single character
         skip_rules        => 1,         # no rules before opts
         attributes        => $dsn_attribs,
         parse_attributes  => $parse_dsn_attribs,
      );
      my @dsn_opts = map {
         my $opts = {
            key  => $_->{spec}->{key},
            dsn  => $_->{spec}->{dsn},
            copy => $_->{spec}->{copy},
            desc => $_->{desc},
         };
         $opts;
      } $dsn_o->_pod_to_specs($file);
      $self->{DSNParser} = DSNParser->new(opts => \@dsn_opts);
   }

   if ( $contents =~ m/^=head1 VERSION\n\n^(.+)$/m ) {
      $self->{version} = $1;
      MKDEBUG && _d($self->{version});
   }

   return;
}

sub DSNParser {
   my ( $self ) = @_;
   return $self->{DSNParser};
};

sub get_defaults_files {
   my ( $self ) = @_;
   return @{$self->{default_files}};
}

sub _pod_to_specs {
   my ( $self, $file ) = @_;
   $file ||= $self->{file} || __FILE__;
   open my $fh, '<', $file or die "Cannot open $file: $OS_ERROR";

   my @specs = ();
   my @rules = ();
   my $para;

   local $INPUT_RECORD_SEPARATOR = '';
   while ( $para = <$fh> ) {
      next unless $para =~ m/^=head1 $self->{head1}/;
      last;
   }

   while ( $para = <$fh> ) {
      last if $para =~ m/^=over/;
      next if $self->{skip_rules};
      chomp $para;
      $para =~ s/\s+/ /g;
      $para =~ s/$POD_link_re/$1/go;
      MKDEBUG && _d('Option rule:', $para);
      push @rules, $para;
   }

   die "POD has no $self->{head1} section" unless $para;

   do {
      if ( my ($option) = $para =~ m/^=item $self->{item}/ ) {
         chomp $para;
         MKDEBUG && _d($para);
         my %attribs;

         $para = <$fh>; # read next paragraph, possibly attributes

         if ( $para =~ m/: / ) { # attributes
            $para =~ s/\s+\Z//g;
            %attribs = map {
                  my ( $attrib, $val) = split(/: /, $_);
                  die "Unrecognized attribute for --$option: $attrib"
                     unless $self->{attributes}->{$attrib};
                  ($attrib, $val);
               } split(/; /, $para);
            if ( $attribs{'short form'} ) {
               $attribs{'short form'} =~ s/-//;
            }
            $para = <$fh>; # read next paragraph, probably short help desc
         }
         else {
            MKDEBUG && _d('Option has no attributes');
         }

         $para =~ s/\s+\Z//g;
         $para =~ s/\s+/ /g;
         $para =~ s/$POD_link_re/$1/go;

         $para =~ s/\.(?:\n.*| [A-Z].*|\Z)//s;
         MKDEBUG && _d('Short help:', $para);

         die "No description after option spec $option" if $para =~ m/^=item/;

         if ( my ($base_option) =  $option =~ m/^\[no\](.*)/ ) {
            $option = $base_option;
            $attribs{'negatable'} = 1;
         }

         push @specs, {
            spec  => $self->{parse_attributes}->($self, $option, \%attribs), 
            desc  => $para
               . (defined $attribs{default} ? " (default $attribs{default})" : ''),
            group => ($attribs{'group'} ? $attribs{'group'} : 'default'),
         };
      }
      while ( $para = <$fh> ) {
         last unless $para;
         if ( $para =~ m/^=head1/ ) {
            $para = undef; # Can't 'last' out of a do {} block.
            last;
         }
         last if $para =~ m/^=item /;
      }
   } while ( $para );

   die "No valid specs in $self->{head1}" unless @specs;

   close $fh;
   return @specs, @rules;
}

sub _parse_specs {
   my ( $self, @specs ) = @_;
   my %disables; # special rule that requires deferred checking

   foreach my $opt ( @specs ) {
      if ( ref $opt ) { # It's an option spec, not a rule.
         MKDEBUG && _d('Parsing opt spec:',
            map { ($_, '=>', $opt->{$_}) } keys %$opt);

         my ( $long, $short ) = $opt->{spec} =~ m/^([\w-]+)(?:\|([^!+=]*))?/;
         if ( !$long ) {
            die "Cannot parse long option from spec $opt->{spec}";
         }
         $opt->{long} = $long;

         die "Duplicate long option --$long" if exists $self->{opts}->{$long};
         $self->{opts}->{$long} = $opt;

         if ( length $long == 1 ) {
            MKDEBUG && _d('Long opt', $long, 'looks like short opt');
            $self->{short_opts}->{$long} = $long;
         }

         if ( $short ) {
            die "Duplicate short option -$short"
               if exists $self->{short_opts}->{$short};
            $self->{short_opts}->{$short} = $long;
            $opt->{short} = $short;
         }
         else {
            $opt->{short} = undef;
         }

         $opt->{is_negatable}  = $opt->{spec} =~ m/!/        ? 1 : 0;
         $opt->{is_cumulative} = $opt->{spec} =~ m/\+/       ? 1 : 0;
         $opt->{is_required}   = $opt->{desc} =~ m/required/ ? 1 : 0;

         $opt->{group} ||= 'default';
         $self->{groups}->{ $opt->{group} }->{$long} = 1;

         $opt->{value} = undef;
         $opt->{got}   = 0;

         my ( $type ) = $opt->{spec} =~ m/=(.)/;
         $opt->{type} = $type;
         MKDEBUG && _d($long, 'type:', $type);


         $opt->{spec} =~ s/=./=s/ if ( $type && $type =~ m/[HhAadzm]/ );

         if ( (my ($def) = $opt->{desc} =~ m/default\b(?: ([^)]+))?/) ) {
            $self->{defaults}->{$long} = defined $def ? $def : 1;
            MKDEBUG && _d($long, 'default:', $def);
         }

         if ( $long eq 'config' ) {
            $self->{defaults}->{$long} = join(',', $self->get_defaults_files());
         }

         if ( (my ($dis) = $opt->{desc} =~ m/(disables .*)/) ) {
            $disables{$long} = $dis;
            MKDEBUG && _d('Deferring check of disables rule for', $opt, $dis);
         }

         $self->{opts}->{$long} = $opt;
      }
      else { # It's an option rule, not a spec.
         MKDEBUG && _d('Parsing rule:', $opt); 
         push @{$self->{rules}}, $opt;
         my @participants = $self->_get_participants($opt);
         my $rule_ok = 0;

         if ( $opt =~ m/mutually exclusive|one and only one/ ) {
            $rule_ok = 1;
            push @{$self->{mutex}}, \@participants;
            MKDEBUG && _d(@participants, 'are mutually exclusive');
         }
         if ( $opt =~ m/at least one|one and only one/ ) {
            $rule_ok = 1;
            push @{$self->{atleast1}}, \@participants;
            MKDEBUG && _d(@participants, 'require at least one');
         }
         if ( $opt =~ m/default to/ ) {
            $rule_ok = 1;
            $self->{defaults_to}->{$participants[0]} = $participants[1];
            MKDEBUG && _d($participants[0], 'defaults to', $participants[1]);
         }
         if ( $opt =~ m/restricted to option groups/ ) {
            $rule_ok = 1;
            my ($groups) = $opt =~ m/groups ([\w\s\,]+)/;
            my @groups = split(',', $groups);
            %{$self->{allowed_groups}->{$participants[0]}} = map {
               s/\s+//;
               $_ => 1;
            } @groups;
         }
         if( $opt =~ m/accepts additional command-line arguments/ ) {
            $rule_ok = 1;
            $self->{strict} = 0;
            MKDEBUG && _d("Strict mode disabled by rule");
         }

         die "Unrecognized option rule: $opt" unless $rule_ok;
      }
   }

   foreach my $long ( keys %disables ) {
      my @participants = $self->_get_participants($disables{$long});
      $self->{disables}->{$long} = \@participants;
      MKDEBUG && _d('Option', $long, 'disables', @participants);
   }

   return; 
}

sub _get_participants {
   my ( $self, $str ) = @_;
   my @participants;
   foreach my $long ( $str =~ m/--(?:\[no\])?([\w-]+)/g ) {
      die "Option --$long does not exist while processing rule $str"
         unless exists $self->{opts}->{$long};
      push @participants, $long;
   }
   MKDEBUG && _d('Participants for', $str, ':', @participants);
   return @participants;
}

sub opts {
   my ( $self ) = @_;
   my %opts = %{$self->{opts}};
   return %opts;
}

sub short_opts {
   my ( $self ) = @_;
   my %short_opts = %{$self->{short_opts}};
   return %short_opts;
}

sub set_defaults {
   my ( $self, %defaults ) = @_;
   $self->{defaults} = {};
   foreach my $long ( keys %defaults ) {
      die "Cannot set default for nonexistent option $long"
         unless exists $self->{opts}->{$long};
      $self->{defaults}->{$long} = $defaults{$long};
      MKDEBUG && _d('Default val for', $long, ':', $defaults{$long});
   }
   return;
}

sub get_defaults {
   my ( $self ) = @_;
   return $self->{defaults};
}

sub get_groups {
   my ( $self ) = @_;
   return $self->{groups};
}

sub _set_option {
   my ( $self, $opt, $val ) = @_;
   my $long = exists $self->{opts}->{$opt}       ? $opt
            : exists $self->{short_opts}->{$opt} ? $self->{short_opts}->{$opt}
            : die "Getopt::Long gave a nonexistent option: $opt";

   $opt = $self->{opts}->{$long};
   if ( $opt->{is_cumulative} ) {
      $opt->{value}++;
   }
   else {
      $opt->{value} = $val;
   }
   $opt->{got} = 1;
   MKDEBUG && _d('Got option', $long, '=', $val);
}

sub get_opts {
   my ( $self ) = @_; 

   foreach my $long ( keys %{$self->{opts}} ) {
      $self->{opts}->{$long}->{got} = 0;
      $self->{opts}->{$long}->{value}
         = exists $self->{defaults}->{$long}       ? $self->{defaults}->{$long}
         : $self->{opts}->{$long}->{is_cumulative} ? 0
         : undef;
   }
   $self->{got_opts} = 0;

   $self->{errors} = [];

   if ( @ARGV && $ARGV[0] eq "--config" ) {
      shift @ARGV;
      $self->_set_option('config', shift @ARGV);
   }
   if ( $self->has('config') ) {
      my @extra_args;
      foreach my $filename ( split(',', $self->get('config')) ) {
         eval {
            push @extra_args, $self->_read_config_file($filename);
         };
         if ( $EVAL_ERROR ) {
            if ( $self->got('config') ) {
               die $EVAL_ERROR;
            }
            elsif ( MKDEBUG ) {
               _d($EVAL_ERROR);
            }
         }
      }
      unshift @ARGV, @extra_args;
   }

   Getopt::Long::Configure('no_ignore_case', 'bundling');
   GetOptions(
      map    { $_->{spec} => sub { $self->_set_option(@_); } }
      grep   { $_->{long} ne 'config' } # --config is handled specially above.
      values %{$self->{opts}}
   ) or $self->save_error('Error parsing options');

   if ( exists $self->{opts}->{version} && $self->{opts}->{version}->{got} ) {
      if ( $self->{version} ) {
         print $self->{version}, "\n";
      }
      else {
         print "Error parsing version.  See the VERSION section of the tool's documentation.\n";
      }
      exit 0;
   }

   if ( @ARGV && $self->{strict} ) {
      $self->save_error("Unrecognized command-line options @ARGV");
   }

   foreach my $mutex ( @{$self->{mutex}} ) {
      my @set = grep { $self->{opts}->{$_}->{got} } @$mutex;
      if ( @set > 1 ) {
         my $err = join(', ', map { "--$self->{opts}->{$_}->{long}" }
                      @{$mutex}[ 0 .. scalar(@$mutex) - 2] )
                 . ' and --'.$self->{opts}->{$mutex->[-1]}->{long}
                 . ' are mutually exclusive.';
         $self->save_error($err);
      }
   }

   foreach my $required ( @{$self->{atleast1}} ) {
      my @set = grep { $self->{opts}->{$_}->{got} } @$required;
      if ( @set == 0 ) {
         my $err = join(', ', map { "--$self->{opts}->{$_}->{long}" }
                      @{$required}[ 0 .. scalar(@$required) - 2] )
                 .' or --'.$self->{opts}->{$required->[-1]}->{long};
         $self->save_error("Specify at least one of $err");
      }
   }

   $self->_check_opts( keys %{$self->{opts}} );
   $self->{got_opts} = 1;
   return;
}

sub _check_opts {
   my ( $self, @long ) = @_;
   my $long_last = scalar @long;
   while ( @long ) {
      foreach my $i ( 0..$#long ) {
         my $long = $long[$i];
         next unless $long;
         my $opt  = $self->{opts}->{$long};
         if ( $opt->{got} ) {
            if ( exists $self->{disables}->{$long} ) {
               my @disable_opts = @{$self->{disables}->{$long}};
               map { $self->{opts}->{$_}->{value} = undef; } @disable_opts;
               MKDEBUG && _d('Unset options', @disable_opts,
                  'because', $long,'disables them');
            }

            if ( exists $self->{allowed_groups}->{$long} ) {

               my @restricted_groups = grep {
                  !exists $self->{allowed_groups}->{$long}->{$_}
               } keys %{$self->{groups}};

               my @restricted_opts;
               foreach my $restricted_group ( @restricted_groups ) {
                  RESTRICTED_OPT:
                  foreach my $restricted_opt (
                     keys %{$self->{groups}->{$restricted_group}} )
                  {
                     next RESTRICTED_OPT if $restricted_opt eq $long;
                     push @restricted_opts, $restricted_opt
                        if $self->{opts}->{$restricted_opt}->{got};
                  }
               }

               if ( @restricted_opts ) {
                  my $err;
                  if ( @restricted_opts == 1 ) {
                     $err = "--$restricted_opts[0]";
                  }
                  else {
                     $err = join(', ',
                               map { "--$self->{opts}->{$_}->{long}" }
                               grep { $_ } 
                               @restricted_opts[0..scalar(@restricted_opts) - 2]
                            )
                          . ' or --'.$self->{opts}->{$restricted_opts[-1]}->{long};
                  }
                  $self->save_error("--$long is not allowed with $err");
               }
            }

         }
         elsif ( $opt->{is_required} ) { 
            $self->save_error("Required option --$long must be specified");
         }

         $self->_validate_type($opt);
         if ( $opt->{parsed} ) {
            delete $long[$i];
         }
         else {
            MKDEBUG && _d('Temporarily failed to parse', $long);
         }
      }

      die "Failed to parse options, possibly due to circular dependencies"
         if @long == $long_last;
      $long_last = @long;
   }

   return;
}

sub _validate_type {
   my ( $self, $opt ) = @_;
   return unless $opt;

   if ( !$opt->{type} ) {
      $opt->{parsed} = 1;
      return;
   }

   my $val = $opt->{value};

   if ( $val && $opt->{type} eq 'm' ) {  # type time
      MKDEBUG && _d('Parsing option', $opt->{long}, 'as a time value');
      my ( $prefix, $num, $suffix ) = $val =~ m/([+-]?)(\d+)([a-z])?$/;
      if ( !$suffix ) {
         my ( $s ) = $opt->{desc} =~ m/\(suffix (.)\)/;
         $suffix = $s || 's';
         MKDEBUG && _d('No suffix given; using', $suffix, 'for',
            $opt->{long}, '(value:', $val, ')');
      }
      if ( $suffix =~ m/[smhd]/ ) {
         $val = $suffix eq 's' ? $num            # Seconds
              : $suffix eq 'm' ? $num * 60       # Minutes
              : $suffix eq 'h' ? $num * 3600     # Hours
              :                  $num * 86400;   # Days
         $opt->{value} = ($prefix || '') . $val;
         MKDEBUG && _d('Setting option', $opt->{long}, 'to', $val);
      }
      else {
         $self->save_error("Invalid time suffix for --$opt->{long}");
      }
   }
   elsif ( $val && $opt->{type} eq 'd' ) {  # type DSN
      MKDEBUG && _d('Parsing option', $opt->{long}, 'as a DSN');
      my $prev = {};
      my $from_key = $self->{defaults_to}->{ $opt->{long} };
      if ( $from_key ) {
         MKDEBUG && _d($opt->{long}, 'DSN copies from', $from_key, 'DSN');
         if ( $self->{opts}->{$from_key}->{parsed} ) {
            $prev = $self->{opts}->{$from_key}->{value};
         }
         else {
            MKDEBUG && _d('Cannot parse', $opt->{long}, 'until',
               $from_key, 'parsed');
            return;
         }
      }
      my $defaults = $self->{DSNParser}->parse_options($self);
      $opt->{value} = $self->{DSNParser}->parse($val, $prev, $defaults);
   }
   elsif ( $val && $opt->{type} eq 'z' ) {  # type size
      MKDEBUG && _d('Parsing option', $opt->{long}, 'as a size value');
      $self->_parse_size($opt, $val);
   }
   elsif ( $opt->{type} eq 'H' || (defined $val && $opt->{type} eq 'h') ) {
      $opt->{value} = { map { $_ => 1 } split(/(?<!\\),\s*/, ($val || '')) };
   }
   elsif ( $opt->{type} eq 'A' || (defined $val && $opt->{type} eq 'a') ) {
      $opt->{value} = [ split(/(?<!\\),\s*/, ($val || '')) ];
   }
   else {
      MKDEBUG && _d('Nothing to validate for option',
         $opt->{long}, 'type', $opt->{type}, 'value', $val);
   }

   $opt->{parsed} = 1;
   return;
}

sub get {
   my ( $self, $opt ) = @_;
   my $long = (length $opt == 1 ? $self->{short_opts}->{$opt} : $opt);
   die "Option $opt does not exist"
      unless $long && exists $self->{opts}->{$long};
   return $self->{opts}->{$long}->{value};
}

sub got {
   my ( $self, $opt ) = @_;
   my $long = (length $opt == 1 ? $self->{short_opts}->{$opt} : $opt);
   die "Option $opt does not exist"
      unless $long && exists $self->{opts}->{$long};
   return $self->{opts}->{$long}->{got};
}

sub has {
   my ( $self, $opt ) = @_;
   my $long = (length $opt == 1 ? $self->{short_opts}->{$opt} : $opt);
   return defined $long ? exists $self->{opts}->{$long} : 0;
}

sub set {
   my ( $self, $opt, $val ) = @_;
   my $long = (length $opt == 1 ? $self->{short_opts}->{$opt} : $opt);
   die "Option $opt does not exist"
      unless $long && exists $self->{opts}->{$long};
   $self->{opts}->{$long}->{value} = $val;
   return;
}

sub save_error {
   my ( $self, $error ) = @_;
   push @{$self->{errors}}, $error;
   return;
}

sub errors {
   my ( $self ) = @_;
   return $self->{errors};
}

sub usage {
   my ( $self ) = @_;
   warn "No usage string is set" unless $self->{usage}; # XXX
   return "Usage: " . ($self->{usage} || '') . "\n";
}

sub descr {
   my ( $self ) = @_;
   warn "No description string is set" unless $self->{description}; # XXX
   my $descr  = ($self->{description} || $self->{program_name} || '')
              . "  For more details, please use the --help option, "
              . "or try 'perldoc $PROGRAM_NAME' "
              . "for complete documentation.";
   $descr = join("\n", $descr =~ m/(.{0,80})(?:\s+|$)/g)
      unless $ENV{DONT_BREAK_LINES};
   $descr =~ s/ +$//mg;
   return $descr;
}

sub usage_or_errors {
   my ( $self, $file, $return ) = @_;
   $file ||= $self->{file} || __FILE__;

   if ( !$self->{description} || !$self->{usage} ) {
      MKDEBUG && _d("Getting description and usage from SYNOPSIS in", $file);
      my %synop = $self->_parse_synopsis($file);
      $self->{description} ||= $synop{description};
      $self->{usage}       ||= $synop{usage};
      MKDEBUG && _d("Description:", $self->{description},
         "\nUsage:", $self->{usage});
   }

   if ( $self->{opts}->{help}->{got} ) {
      print $self->print_usage() or die "Cannot print usage: $OS_ERROR";
      exit 0 unless $return;
   }
   elsif ( scalar @{$self->{errors}} ) {
      print $self->print_errors() or die "Cannot print errors: $OS_ERROR";
      exit 0 unless $return;
   }

   return;
}

sub print_errors {
   my ( $self ) = @_;
   my $usage = $self->usage() . "\n";
   if ( (my @errors = @{$self->{errors}}) ) {
      $usage .= join("\n  * ", 'Errors in command-line arguments:', @errors)
              . "\n";
   }
   return $usage . "\n" . $self->descr();
}

sub print_usage {
   my ( $self ) = @_;
   die "Run get_opts() before print_usage()" unless $self->{got_opts};
   my @opts = values %{$self->{opts}};

   my $maxl = max(
      map {
         length($_->{long})               # option long name
         + ($_->{is_negatable} ? 4 : 0)   # "[no]" if opt is negatable
         + ($_->{type} ? 2 : 0)           # "=x" where x is the opt type
      }
      @opts);

   my $maxs = max(0,
      map {
         length($_)
         + ($self->{opts}->{$_}->{is_negatable} ? 4 : 0)
         + ($self->{opts}->{$_}->{type} ? 2 : 0)
      }
      values %{$self->{short_opts}});

   my $lcol = max($maxl, ($maxs + 3));
   my $rcol = 80 - $lcol - 6;
   my $rpad = ' ' x ( 80 - $rcol );

   $maxs = max($lcol - 3, $maxs);

   my $usage = $self->descr() . "\n" . $self->usage();

   my @groups = reverse sort grep { $_ ne 'default'; } keys %{$self->{groups}};
   push @groups, 'default';

   foreach my $group ( reverse @groups ) {
      $usage .= "\n".($group eq 'default' ? 'Options' : $group).":\n\n";
      foreach my $opt (
         sort { $a->{long} cmp $b->{long} }
         grep { $_->{group} eq $group }
         @opts )
      {
         my $long  = $opt->{is_negatable} ? "[no]$opt->{long}" : $opt->{long};
         my $short = $opt->{short};
         my $desc  = $opt->{desc};

         $long .= $opt->{type} ? "=$opt->{type}" : "";

         if ( $opt->{type} && $opt->{type} eq 'm' ) {
            my ($s) = $desc =~ m/\(suffix (.)\)/;
            $s    ||= 's';
            $desc =~ s/\s+\(suffix .\)//;
            $desc .= ".  Optional suffix s=seconds, m=minutes, h=hours, "
                   . "d=days; if no suffix, $s is used.";
         }
         $desc = join("\n$rpad", grep { $_ } $desc =~ m/(.{0,$rcol})(?:\s+|$)/g);
         $desc =~ s/ +$//mg;
         if ( $short ) {
            $usage .= sprintf("  --%-${maxs}s -%s  %s\n", $long, $short, $desc);
         }
         else {
            $usage .= sprintf("  --%-${lcol}s  %s\n", $long, $desc);
         }
      }
   }

   $usage .= "\nOption types: s=string, i=integer, f=float, h/H/a/A=comma-separated list, d=DSN, z=size, m=time\n";

   if ( (my @rules = @{$self->{rules}}) ) {
      $usage .= "\nRules:\n\n";
      $usage .= join("\n", map { "  $_" } @rules) . "\n";
   }
   if ( $self->{DSNParser} ) {
      $usage .= "\n" . $self->{DSNParser}->usage();
   }
   $usage .= "\nOptions and values after processing arguments:\n\n";
   foreach my $opt ( sort { $a->{long} cmp $b->{long} } @opts ) {
      my $val   = $opt->{value};
      my $type  = $opt->{type} || '';
      my $bool  = $opt->{spec} =~ m/^[\w-]+(?:\|[\w-])?!?$/;
      $val      = $bool              ? ( $val ? 'TRUE' : 'FALSE' )
                : !defined $val      ? '(No value)'
                : $type eq 'd'       ? $self->{DSNParser}->as_string($val)
                : $type =~ m/H|h/    ? join(',', sort keys %$val)
                : $type =~ m/A|a/    ? join(',', @$val)
                :                    $val;
      $usage .= sprintf("  --%-${lcol}s  %s\n", $opt->{long}, $val);
   }
   return $usage;
}

sub prompt_noecho {
   shift @_ if ref $_[0] eq __PACKAGE__;
   my ( $prompt ) = @_;
   local $OUTPUT_AUTOFLUSH = 1;
   print $prompt
      or die "Cannot print: $OS_ERROR";
   my $response;
   eval {
      require Term::ReadKey;
      Term::ReadKey::ReadMode('noecho');
      chomp($response = <STDIN>);
      Term::ReadKey::ReadMode('normal');
      print "\n"
         or die "Cannot print: $OS_ERROR";
   };
   if ( $EVAL_ERROR ) {
      die "Cannot read response; is Term::ReadKey installed? $EVAL_ERROR";
   }
   return $response;
}

sub _read_config_file {
   my ( $self, $filename ) = @_;
   open my $fh, "<", $filename or die "Cannot open $filename: $OS_ERROR\n";
   my @args;
   my $prefix = '--';
   my $parse  = 1;

   LINE:
   while ( my $line = <$fh> ) {
      chomp $line;
      next LINE if $line =~ m/^\s*(?:\#|\;|$)/;
      $line =~ s/\s+#.*$//g;
      $line =~ s/^\s+|\s+$//g;
      if ( $line eq '--' ) {
         $prefix = '';
         $parse  = 0;
         next LINE;
      }
      if ( $parse
         && (my($opt, $arg) = $line =~ m/^\s*([^=\s]+?)(?:\s*=\s*(.*?)\s*)?$/)
      ) {
         push @args, grep { defined $_ } ("$prefix$opt", $arg);
      }
      elsif ( $line =~ m/./ ) {
         push @args, $line;
      }
      else {
         die "Syntax error in file $filename at line $INPUT_LINE_NUMBER";
      }
   }
   close $fh;
   return @args;
}

sub read_para_after {
   my ( $self, $file, $regex ) = @_;
   open my $fh, "<", $file or die "Can't open $file: $OS_ERROR";
   local $INPUT_RECORD_SEPARATOR = '';
   my $para;
   while ( $para = <$fh> ) {
      next unless $para =~ m/^=pod$/m;
      last;
   }
   while ( $para = <$fh> ) {
      next unless $para =~ m/$regex/;
      last;
   }
   $para = <$fh>;
   chomp($para);
   close $fh or die "Can't close $file: $OS_ERROR";
   return $para;
}

sub clone {
   my ( $self ) = @_;

   my %clone = map {
      my $hashref  = $self->{$_};
      my $val_copy = {};
      foreach my $key ( keys %$hashref ) {
         my $ref = ref $hashref->{$key};
         $val_copy->{$key} = !$ref           ? $hashref->{$key}
                           : $ref eq 'HASH'  ? { %{$hashref->{$key}} }
                           : $ref eq 'ARRAY' ? [ @{$hashref->{$key}} ]
                           : $hashref->{$key};
      }
      $_ => $val_copy;
   } qw(opts short_opts defaults);

   foreach my $scalar ( qw(got_opts) ) {
      $clone{$scalar} = $self->{$scalar};
   }

   return bless \%clone;     
}

sub _parse_size {
   my ( $self, $opt, $val ) = @_;

   if ( lc($val || '') eq 'null' ) {
      MKDEBUG && _d('NULL size for', $opt->{long});
      $opt->{value} = 'null';
      return;
   }

   my %factor_for = (k => 1_024, M => 1_048_576, G => 1_073_741_824);
   my ($pre, $num, $factor) = $val =~ m/^([+-])?(\d+)([kMG])?$/;
   if ( defined $num ) {
      if ( $factor ) {
         $num *= $factor_for{$factor};
         MKDEBUG && _d('Setting option', $opt->{y},
            'to num', $num, '* factor', $factor);
      }
      $opt->{value} = ($pre || '') . $num;
   }
   else {
      $self->save_error("Invalid size for --$opt->{long}");
   }
   return;
}

sub _parse_attribs {
   my ( $self, $option, $attribs ) = @_;
   my $types = $self->{types};
   return $option
      . ($attribs->{'short form'} ? '|' . $attribs->{'short form'}   : '' )
      . ($attribs->{'negatable'}  ? '!'                              : '' )
      . ($attribs->{'cumulative'} ? '+'                              : '' )
      . ($attribs->{'type'}       ? '=' . $types->{$attribs->{type}} : '' );
}

sub _parse_synopsis {
   my ( $self, $file ) = @_;
   $file ||= $self->{file} || __FILE__;
   MKDEBUG && _d("Parsing SYNOPSIS in", $file);

   local $INPUT_RECORD_SEPARATOR = '';  # read paragraphs
   open my $fh, "<", $file or die "Cannot open $file: $OS_ERROR";
   my $para;
   1 while defined($para = <$fh>) && $para !~ m/^=head1 SYNOPSIS/;
   die "$file does not contain a SYNOPSIS section" unless $para;
   my @synop;
   for ( 1..2 ) {  # 1 for the usage, 2 for the description
      my $para = <$fh>;
      push @synop, $para;
   }
   close $fh;
   MKDEBUG && _d("Raw SYNOPSIS text:", @synop);
   my ($usage, $desc) = @synop;
   die "The SYNOPSIS section in $file is not formatted properly"
      unless $usage && $desc;

   $usage =~ s/^\s*Usage:\s+(.+)/$1/;
   chomp $usage;

   $desc =~ s/\n/ /g;
   $desc =~ s/\s{2,}/ /g;
   $desc =~ s/\. ([A-Z][a-z])/.  $1/g;
   $desc =~ s/\s+$//;

   return (
      description => $desc,
      usage       => $usage,
   );
};

sub _d {
   my ($package, undef, $line) = caller 0;
   @_ = map { (my $temp = $_) =~ s/\n/\n# /g; $temp; }
        map { defined $_ ? $_ : 'undef' }
        @_;
   print STDERR "# $package:$line $PID ", join(' ', @_), "\n";
}

if ( MKDEBUG ) {
   print '# ', $^X, ' ', $], "\n";
   if ( my $uname = `uname -a` ) {
      $uname =~ s/\s+/ /g;
      print "# $uname\n";
   }
   print '# Arguments: ',
      join(' ', map { my $a = "_[$_]_"; $a =~ s/\n/\n# /g; $a; } @ARGV), "\n";
}

1;
}
# ###########################################################################
# End OptionParser package
# ###########################################################################

# ###########################################################################
# DSNParser package
# This package is a copy without comments from the original.  The original
# with comments and its test file can be found in the Bazaar repository at,
#   lib/DSNParser.pm
#   t/lib/DSNParser.t
# See https://launchpad.net/percona-toolkit for more information.
# ###########################################################################
{
package DSNParser;

use strict;
use warnings FATAL => 'all';
use English qw(-no_match_vars);
use constant MKDEBUG => $ENV{MKDEBUG} || 0;

use Data::Dumper;
$Data::Dumper::Indent    = 0;
$Data::Dumper::Quotekeys = 0;

eval {
   require DBI;
};
my $have_dbi = $EVAL_ERROR ? 0 : 1;

sub new {
   my ( $class, %args ) = @_;
   foreach my $arg ( qw(opts) ) {
      die "I need a $arg argument" unless $args{$arg};
   }
   my $self = {
      opts => {}  # h, P, u, etc.  Should come from DSN OPTIONS section in POD.
   };
   foreach my $opt ( @{$args{opts}} ) {
      if ( !$opt->{key} || !$opt->{desc} ) {
         die "Invalid DSN option: ", Dumper($opt);
      }
      MKDEBUG && _d('DSN option:',
         join(', ',
            map { "$_=" . (defined $opt->{$_} ? ($opt->{$_} || '') : 'undef') }
               keys %$opt
         )
      );
      $self->{opts}->{$opt->{key}} = {
         dsn  => $opt->{dsn},
         desc => $opt->{desc},
         copy => $opt->{copy} || 0,
      };
   }
   return bless $self, $class;
}

sub prop {
   my ( $self, $prop, $value ) = @_;
   if ( @_ > 2 ) {
      MKDEBUG && _d('Setting', $prop, 'property');
      $self->{$prop} = $value;
   }
   return $self->{$prop};
}

sub parse {
   my ( $self, $dsn, $prev, $defaults ) = @_;
   if ( !$dsn ) {
      MKDEBUG && _d('No DSN to parse');
      return;
   }
   MKDEBUG && _d('Parsing', $dsn);
   $prev     ||= {};
   $defaults ||= {};
   my %given_props;
   my %final_props;
   my $opts = $self->{opts};

   foreach my $dsn_part ( split(/,/, $dsn) ) {
      if ( my ($prop_key, $prop_val) = $dsn_part =~  m/^(.)=(.*)$/ ) {
         $given_props{$prop_key} = $prop_val;
      }
      else {
         MKDEBUG && _d('Interpreting', $dsn_part, 'as h=', $dsn_part);
         $given_props{h} = $dsn_part;
      }
   }

   foreach my $key ( keys %$opts ) {
      MKDEBUG && _d('Finding value for', $key);
      $final_props{$key} = $given_props{$key};
      if (   !defined $final_props{$key}
           && defined $prev->{$key} && $opts->{$key}->{copy} )
      {
         $final_props{$key} = $prev->{$key};
         MKDEBUG && _d('Copying value for', $key, 'from previous DSN');
      }
      if ( !defined $final_props{$key} ) {
         $final_props{$key} = $defaults->{$key};
         MKDEBUG && _d('Copying value for', $key, 'from defaults');
      }
   }

   foreach my $key ( keys %given_props ) {
      die "Unknown DSN option '$key' in '$dsn'.  For more details, "
            . "please use the --help option, or try 'perldoc $PROGRAM_NAME' "
            . "for complete documentation."
         unless exists $opts->{$key};
   }
   if ( (my $required = $self->prop('required')) ) {
      foreach my $key ( keys %$required ) {
         die "Missing required DSN option '$key' in '$dsn'.  For more details, "
               . "please use the --help option, or try 'perldoc $PROGRAM_NAME' "
               . "for complete documentation."
            unless $final_props{$key};
      }
   }

   return \%final_props;
}

sub parse_options {
   my ( $self, $o ) = @_;
   die 'I need an OptionParser object' unless ref $o eq 'OptionParser';
   my $dsn_string
      = join(',',
          map  { "$_=".$o->get($_); }
          grep { $o->has($_) && $o->get($_) }
          keys %{$self->{opts}}
        );
   MKDEBUG && _d('DSN string made from options:', $dsn_string);
   return $self->parse($dsn_string);
}

sub as_string {
   my ( $self, $dsn, $props ) = @_;
   return $dsn unless ref $dsn;
   my %allowed = $props ? map { $_=>1 } @$props : ();
   return join(',',
      map  { "$_=" . ($_ eq 'p' ? '...' : $dsn->{$_})  }
      grep { defined $dsn->{$_} && $self->{opts}->{$_} }
      grep { !$props || $allowed{$_}                   }
      sort keys %$dsn );
}

sub usage {
   my ( $self ) = @_;
   my $usage
      = "DSN syntax is key=value[,key=value...]  Allowable DSN keys:\n\n"
      . "  KEY  COPY  MEANING\n"
      . "  ===  ====  =============================================\n";
   my %opts = %{$self->{opts}};
   foreach my $key ( sort keys %opts ) {
      $usage .= "  $key    "
             .  ($opts{$key}->{copy} ? 'yes   ' : 'no    ')
             .  ($opts{$key}->{desc} || '[No description]')
             . "\n";
   }
   $usage .= "\n  If the DSN is a bareword, the word is treated as the 'h' key.\n";
   return $usage;
}

sub get_cxn_params {
   my ( $self, $info ) = @_;
   my $dsn;
   my %opts = %{$self->{opts}};
   my $driver = $self->prop('dbidriver') || '';
   if ( $driver eq 'Pg' ) {
      $dsn = 'DBI:Pg:dbname=' . ( $info->{D} || '' ) . ';'
         . join(';', map  { "$opts{$_}->{dsn}=$info->{$_}" }
                     grep { defined $info->{$_} }
                     qw(h P));
   }
   else {
      $dsn = 'DBI:mysql:' . ( $info->{D} || '' ) . ';'
         . join(';', map  { "$opts{$_}->{dsn}=$info->{$_}" }
                     grep { defined $info->{$_} }
                     qw(F h P S A))
         . ';mysql_read_default_group=client';
   }
   MKDEBUG && _d($dsn);
   return ($dsn, $info->{u}, $info->{p});
}

sub fill_in_dsn {
   my ( $self, $dbh, $dsn ) = @_;
   my $vars = $dbh->selectall_hashref('SHOW VARIABLES', 'Variable_name');
   my ($user, $db) = $dbh->selectrow_array('SELECT USER(), DATABASE()');
   $user =~ s/@.*//;
   $dsn->{h} ||= $vars->{hostname}->{Value};
   $dsn->{S} ||= $vars->{'socket'}->{Value};
   $dsn->{P} ||= $vars->{port}->{Value};
   $dsn->{u} ||= $user;
   $dsn->{D} ||= $db;
}

sub get_dbh {
   my ( $self, $cxn_string, $user, $pass, $opts ) = @_;
   $opts ||= {};
   my $defaults = {
      AutoCommit         => 0,
      RaiseError         => 1,
      PrintError         => 0,
      ShowErrorStatement => 1,
      mysql_enable_utf8 => ($cxn_string =~ m/charset=utf8/i ? 1 : 0),
   };
   @{$defaults}{ keys %$opts } = values %$opts;

   if ( $opts->{mysql_use_result} ) {
      $defaults->{mysql_use_result} = 1;
   }

   if ( !$have_dbi ) {
      die "Cannot connect to MySQL because the Perl DBI module is not "
         . "installed or not found.  Run 'perl -MDBI' to see the directories "
         . "that Perl searches for DBI.  If DBI is not installed, try:\n"
         . "  Debian/Ubuntu  apt-get install libdbi-perl\n"
         . "  RHEL/CentOS    yum install perl-DBI\n"
         . "  OpenSolaris    pgk install pkg:/SUNWpmdbi\n";

   }

   my $dbh;
   my $tries = 2;
   while ( !$dbh && $tries-- ) {
      MKDEBUG && _d($cxn_string, ' ', $user, ' ', $pass, 
         join(', ', map { "$_=>$defaults->{$_}" } keys %$defaults ));

      eval {
         $dbh = DBI->connect($cxn_string, $user, $pass, $defaults);

         if ( $cxn_string =~ m/mysql/i ) {
            my $sql;

            $sql = 'SELECT @@SQL_MODE';
            MKDEBUG && _d($dbh, $sql);
            my ($sql_mode) = $dbh->selectrow_array($sql);

            $sql = 'SET @@SQL_QUOTE_SHOW_CREATE = 1'
                 . '/*!40101, @@SQL_MODE=\'NO_AUTO_VALUE_ON_ZERO'
                 . ($sql_mode ? ",$sql_mode" : '')
                 . '\'*/';
            MKDEBUG && _d($dbh, $sql);
            $dbh->do($sql);

            if ( my ($charset) = $cxn_string =~ m/charset=(\w+)/ ) {
               $sql = "/*!40101 SET NAMES $charset*/";
               MKDEBUG && _d($dbh, ':', $sql);
               $dbh->do($sql);
               MKDEBUG && _d('Enabling charset for STDOUT');
               if ( $charset eq 'utf8' ) {
                  binmode(STDOUT, ':utf8')
                     or die "Can't binmode(STDOUT, ':utf8'): $OS_ERROR";
               }
               else {
                  binmode(STDOUT) or die "Can't binmode(STDOUT): $OS_ERROR";
               }
            }

            if ( $self->prop('set-vars') ) {
               $sql = "SET " . $self->prop('set-vars');
               MKDEBUG && _d($dbh, ':', $sql);
               $dbh->do($sql);
            }
         }
      };
      if ( !$dbh && $EVAL_ERROR ) {
         MKDEBUG && _d($EVAL_ERROR);
         if ( $EVAL_ERROR =~ m/not a compiled character set|character set utf8/ ) {
            MKDEBUG && _d('Going to try again without utf8 support');
            delete $defaults->{mysql_enable_utf8};
         }
         elsif ( $EVAL_ERROR =~ m/locate DBD\/mysql/i ) {
            die "Cannot connect to MySQL because the Perl DBD::mysql module is "
               . "not installed or not found.  Run 'perl -MDBD::mysql' to see "
               . "the directories that Perl searches for DBD::mysql.  If "
               . "DBD::mysql is not installed, try:\n"
               . "  Debian/Ubuntu  apt-get install libdbd-mysql-perl\n"
               . "  RHEL/CentOS    yum install perl-DBD-MySQL\n"
               . "  OpenSolaris    pgk install pkg:/SUNWapu13dbd-mysql\n";
         }
         if ( !$tries ) {
            die $EVAL_ERROR;
         }
      }
   }

   MKDEBUG && _d('DBH info: ',
      $dbh,
      Dumper($dbh->selectrow_hashref(
         'SELECT DATABASE(), CONNECTION_ID(), VERSION()/*!50038 , @@hostname*/')),
      'Connection info:',      $dbh->{mysql_hostinfo},
      'Character set info:',   Dumper($dbh->selectall_arrayref(
                     'SHOW VARIABLES LIKE "character_set%"', { Slice => {}})),
      '$DBD::mysql::VERSION:', $DBD::mysql::VERSION,
      '$DBI::VERSION:',        $DBI::VERSION,
   );

   return $dbh;
}

sub get_hostname {
   my ( $self, $dbh ) = @_;
   if ( my ($host) = ($dbh->{mysql_hostinfo} || '') =~ m/^(\w+) via/ ) {
      return $host;
   }
   my ( $hostname, $one ) = $dbh->selectrow_array(
      'SELECT /*!50038 @@hostname, */ 1');
   return $hostname;
}

sub disconnect {
   my ( $self, $dbh ) = @_;
   MKDEBUG && $self->print_active_handles($dbh);
   $dbh->disconnect;
}

sub print_active_handles {
   my ( $self, $thing, $level ) = @_;
   $level ||= 0;
   printf("# Active %sh: %s %s %s\n", ($thing->{Type} || 'undef'), "\t" x $level,
      $thing, (($thing->{Type} || '') eq 'st' ? $thing->{Statement} || '' : ''))
      or die "Cannot print: $OS_ERROR";
   foreach my $handle ( grep {defined} @{ $thing->{ChildHandles} } ) {
      $self->print_active_handles( $handle, $level + 1 );
   }
}

sub copy {
   my ( $self, $dsn_1, $dsn_2, %args ) = @_;
   die 'I need a dsn_1 argument' unless $dsn_1;
   die 'I need a dsn_2 argument' unless $dsn_2;
   my %new_dsn = map {
      my $key = $_;
      my $val;
      if ( $args{overwrite} ) {
         $val = defined $dsn_1->{$key} ? $dsn_1->{$key} : $dsn_2->{$key};
      }
      else {
         $val = defined $dsn_2->{$key} ? $dsn_2->{$key} : $dsn_1->{$key};
      }
      $key => $val;
   } keys %{$self->{opts}};
   return \%new_dsn;
}

sub _d {
   my ($package, undef, $line) = caller 0;
   @_ = map { (my $temp = $_) =~ s/\n/\n# /g; $temp; }
        map { defined $_ ? $_ : 'undef' }
        @_;
   print STDERR "# $package:$line $PID ", join(' ', @_), "\n";
}

1;
}
# ###########################################################################
# End DSNParser package
# ###########################################################################

# ###########################################################################
# Daemon package
# This package is a copy without comments from the original.  The original
# with comments and its test file can be found in the Bazaar repository at,
#   lib/Daemon.pm
#   t/lib/Daemon.t
# See https://launchpad.net/percona-toolkit for more information.
# ###########################################################################
{
package Daemon;

use strict;
use warnings FATAL => 'all';
use English qw(-no_match_vars);
use constant MKDEBUG => $ENV{MKDEBUG} || 0;

use POSIX qw(setsid);

sub new {
   my ( $class, %args ) = @_;
   foreach my $arg ( qw(o) ) {
      die "I need a $arg argument" unless $args{$arg};
   }
   my $o = $args{o};
   my $self = {
      o        => $o,
      log_file => $o->has('log') ? $o->get('log') : undef,
      PID_file => $o->has('pid') ? $o->get('pid') : undef,
   };

   check_PID_file(undef, $self->{PID_file});

   MKDEBUG && _d('Daemonized child will log to', $self->{log_file});
   return bless $self, $class;
}

sub daemonize {
   my ( $self ) = @_;

   MKDEBUG && _d('About to fork and daemonize');
   defined (my $pid = fork()) or die "Cannot fork: $OS_ERROR";
   if ( $pid ) {
      MKDEBUG && _d('I am the parent and now I die');
      exit;
   }

   $self->{PID_owner} = $PID;
   $self->{child}     = 1;

   POSIX::setsid() or die "Cannot start a new session: $OS_ERROR";
   chdir '/'       or die "Cannot chdir to /: $OS_ERROR";

   $self->_make_PID_file();

   $OUTPUT_AUTOFLUSH = 1;

   if ( -t STDIN ) {
      close STDIN;
      open  STDIN, '/dev/null'
         or die "Cannot reopen STDIN to /dev/null: $OS_ERROR";
   }

   if ( $self->{log_file} ) {
      close STDOUT;
      open  STDOUT, '>>', $self->{log_file}
         or die "Cannot open log file $self->{log_file}: $OS_ERROR";

      close STDERR;
      open  STDERR, ">&STDOUT"
         or die "Cannot dupe STDERR to STDOUT: $OS_ERROR"; 
   }
   else {
      if ( -t STDOUT ) {
         close STDOUT;
         open  STDOUT, '>', '/dev/null'
            or die "Cannot reopen STDOUT to /dev/null: $OS_ERROR";
      }
      if ( -t STDERR ) {
         close STDERR;
         open  STDERR, '>', '/dev/null'
            or die "Cannot reopen STDERR to /dev/null: $OS_ERROR";
      }
   }

   MKDEBUG && _d('I am the child and now I live daemonized');
   return;
}

sub check_PID_file {
   my ( $self, $file ) = @_;
   my $PID_file = $self ? $self->{PID_file} : $file;
   MKDEBUG && _d('Checking PID file', $PID_file);
   if ( $PID_file && -f $PID_file ) {
      my $pid;
      eval { chomp($pid = `cat $PID_file`); };
      die "Cannot cat $PID_file: $OS_ERROR" if $EVAL_ERROR;
      MKDEBUG && _d('PID file exists; it contains PID', $pid);
      if ( $pid ) {
         my $pid_is_alive = kill 0, $pid;
         if ( $pid_is_alive ) {
            die "The PID file $PID_file already exists "
               . " and the PID that it contains, $pid, is running";
         }
         else {
            warn "Overwriting PID file $PID_file because the PID that it "
               . "contains, $pid, is not running";
         }
      }
      else {
         die "The PID file $PID_file already exists but it does not "
            . "contain a PID";
      }
   }
   else {
      MKDEBUG && _d('No PID file');
   }
   return;
}

sub make_PID_file {
   my ( $self ) = @_;
   if ( exists $self->{child} ) {
      die "Do not call Daemon::make_PID_file() for daemonized scripts";
   }
   $self->_make_PID_file();
   $self->{PID_owner} = $PID;
   return;
}

sub _make_PID_file {
   my ( $self ) = @_;

   my $PID_file = $self->{PID_file};
   if ( !$PID_file ) {
      MKDEBUG && _d('No PID file to create');
      return;
   }

   $self->check_PID_file();

   open my $PID_FH, '>', $PID_file
      or die "Cannot open PID file $PID_file: $OS_ERROR";
   print $PID_FH $PID
      or die "Cannot print to PID file $PID_file: $OS_ERROR";
   close $PID_FH
      or die "Cannot close PID file $PID_file: $OS_ERROR";

   MKDEBUG && _d('Created PID file:', $self->{PID_file});
   return;
}

sub _remove_PID_file {
   my ( $self ) = @_;
   if ( $self->{PID_file} && -f $self->{PID_file} ) {
      unlink $self->{PID_file}
         or warn "Cannot remove PID file $self->{PID_file}: $OS_ERROR";
      MKDEBUG && _d('Removed PID file');
   }
   else {
      MKDEBUG && _d('No PID to remove');
   }
   return;
}

sub DESTROY {
   my ( $self ) = @_;

   $self->_remove_PID_file() if ($self->{PID_owner} || 0) == $PID;

   return;
}

sub _d {
   my ($package, undef, $line) = caller 0;
   @_ = map { (my $temp = $_) =~ s/\n/\n# /g; $temp; }
        map { defined $_ ? $_ : 'undef' }
        @_;
   print STDERR "# $package:$line $PID ", join(' ', @_), "\n";
}

1;
}
# ###########################################################################
# End Daemon package
# ###########################################################################

# ###########################################################################
# TextResultSetParser package
# This package is a copy without comments from the original.  The original
# with comments and its test file can be found in the Bazaar repository at,
#   lib/TextResultSetParser.pm
#   t/lib/TextResultSetParser.t
# See https://launchpad.net/percona-toolkit for more information.
# ###########################################################################
{
package TextResultSetParser;

use strict;
use warnings FATAL => 'all';
use English qw(-no_match_vars);
use constant MKDEBUG => $ENV{MKDEBUG} || 0;

sub new {
   my ( $class, %args ) = @_;
   my %value_for = (
      'NULL' => undef,  # DBI::selectall_arrayref() does this
      ($args{value_for} ? %{$args{value_for}} : ()),
   );
   my $self = {
      %args,
      value_for => \%value_for,
   };
   return bless $self, $class;
}

sub _parse_tabular {
   my ( $text, @cols ) = @_;
   my %row;
   my @vals = $text =~ m/\| +([^\|]*?)(?= +\|)/msg;
   return (undef, \@vals) unless @cols;
   @row{@cols} = @vals;
   return (\%row, undef);
}

sub _parse_tab_sep {
   my ( $text, @cols ) = @_;
   my %row;
   my @vals = split(/\t/, $text);
   return (undef, \@vals) unless @cols;
   @row{@cols} = @vals;
   return (\%row, undef);
}

sub parse_vertical_row {
   my ( $self, $text ) = @_;
   my %row = $text =~ m/^\s*(\w+):(?: ([^\n]*))?/msg;
   if ( $self->{NAME_lc} ) {
      my %lc_row = map {
         my $key = lc $_;
         $key => $row{$_};
      } keys %row;
      return \%lc_row;
   }
   else {
      return \%row;
   }
}

sub parse {
   my ( $self, $text ) = @_;
   my $result_set;

   if ( $text =~ m/^\+---/m ) { # standard "tabular" output
      MKDEBUG && _d('Result set text is standard tabular');
      my $line_pattern  = qr/^(\| .*)[\r\n]+/m;
      $result_set
         = $self->parse_horizontal_row($text, $line_pattern, \&_parse_tabular);
   }
   elsif ( $text =~ m/^\w+\t\w+/m ) { # tab-separated
      MKDEBUG && _d('Result set text is tab-separated');
      my $line_pattern  = qr/^(.*?\t.*)[\r\n]+/m;
      $result_set
         = $self->parse_horizontal_row($text, $line_pattern, \&_parse_tab_sep);
   }
   elsif ( $text =~ m/\*\*\* \d+\. row/ ) { # "vertical" output
      MKDEBUG && _d('Result set text is vertical (\G)');
      foreach my $row ( split_vertical_rows($text) ) {
         push @$result_set, $self->parse_vertical_row($row);
      }
   }
   else {
      my $text_sample = substr $text, 0, 300;
      my $remaining   = length $text > 300 ? (length $text) - 300 : 0;
      chomp $text_sample;
      die "Cannot determine if text is tabular, tab-separated or vertical:\n"
         . "$text_sample\n"
         . ($remaining ? "(not showing last $remaining bytes of text)\n" : "");
   }

   if ( $self->{value_for} ) {
      foreach my $result_set ( @$result_set ) {
         foreach my $key ( keys %$result_set ) {
            next unless defined $result_set->{$key};
            $result_set->{$key} = $self->{value_for}->{ $result_set->{$key} }
               if exists $self->{value_for}->{ $result_set->{$key} };
         }
      }
   }

   return $result_set;
}


sub parse_horizontal_row {
   my ( $self, $text, $line_pattern, $sub ) = @_;
   my @result_sets = ();
   my @cols        = ();
   foreach my $line ( $text =~ m/$line_pattern/g ) {
      my ( $row, $cols ) = $sub->($line, @cols);
      if ( $row ) {
         push @result_sets, $row;
      }
      else {
         @cols = map { $self->{NAME_lc} ? lc $_ : $_ } @$cols;
      }
   }
   return \@result_sets;
}

sub split_vertical_rows {
   my ( $text ) = @_;
   my $ROW_HEADER = '\*{3,} \d+\. row \*{3,}';
   my @rows = $text =~ m/($ROW_HEADER.*?)(?=$ROW_HEADER|\z)/omgs;
   return @rows;
}

sub _d {
   my ($package, undef, $line) = caller 0;
   @_ = map { (my $temp = $_) =~ s/\n/\n# /g; $temp; }
        map { defined $_ ? $_ : 'undef' }
        @_;
   print STDERR "# $package:$line $PID ", join(' ', @_), "\n";
}

1;
}
# ###########################################################################
# End TextResultSetParser package
# ###########################################################################

# ###########################################################################
# MySQLConfig package
# This package is a copy without comments from the original.  The original
# with comments and its test file can be found in the Bazaar repository at,
#   lib/MySQLConfig.pm
#   t/lib/MySQLConfig.t
# See https://launchpad.net/percona-toolkit for more information.
# ###########################################################################
{
package MySQLConfig;

use strict;
use warnings FATAL => 'all';
use English qw(-no_match_vars);
use constant MKDEBUG => $ENV{MKDEBUG} || 0;

my %can_be_duplicate = (
   replicate_wild_do_table     => 1,
   replicate_wild_ignore_table => 1,
   replicate_rewrite_db        => 1,
   replicate_ignore_table      => 1,
   replicate_ignore_db         => 1,
   replicate_do_table          => 1,
   replicate_do_db             => 1,
);

sub new {
   my ( $class, %args ) = @_;
   my @requires_one_of = qw(file output result_set dbh);
   my $required_arg    = grep { $args{$_} } @requires_one_of;
   if ( !$required_arg ) {
      die "I need a " . join(', ', @requires_one_of[0..$#requires_one_of-1])
         . " or " . $requires_one_of[-1] . " argument";
   }
   if ( $required_arg > 1 ) {
      die "Specify only one "
         . join(', ', @requires_one_of[0..$#requires_one_of-1])
         . " or " . $requires_one_of[-1] . " argument";
   }
   if ( $args{file} || $args{output} ) {
      die "I need a TextResultSetParser argument"
         unless $args{TextResultSetParser};
   }

   if ( $args{file} ) {
      $args{output} = _slurp_file($args{file});
   }

   my %config_data = _parse_config(%args);

   my $self = {
      %args,
      %config_data,
   };

   return bless $self, $class;
}

sub _parse_config {
   my ( %args ) = @_;

   my %config_data;
   if ( $args{output} ) {
      %config_data = _parse_config_output(%args);
   }
   elsif ( my $rows = $args{result_set} ) {
      $config_data{format} = $args{format} || 'show_variables';
      $config_data{vars}   = { map { @$_ } @$rows };
   }
   elsif ( my $dbh = $args{dbh} ) {
      $config_data{format} = $args{format} || 'show_variables';
      my $sql = "SHOW /*!40103 GLOBAL*/ VARIABLES";
      MKDEBUG && _d($dbh, $sql);
      my $rows = $dbh->selectall_arrayref($sql);
      $config_data{vars} = { map { @$_ } @$rows };
      $config_data{mysql_version} = _get_version($dbh);
   }
   else {
      die "Unknown config source";
   }

   return %config_data;
}

sub _parse_config_output {
   my ( %args ) = @_;
   my @required_args = qw(output TextResultSetParser);
   foreach my $arg ( @required_args ) {
      die "I need a $arg arugment" unless $args{$arg};
   }
   my ($output) = @args{@required_args};
   MKDEBUG && _d("Parsing config output");

   my $format = $args{format} || detect_config_output_format(%args);
   if ( !$format ) {
      die "Cannot auto-detect the MySQL config format";
   }

   my $vars;      # variables hashref
   my $dupes;     # duplicate vars hashref
   my $opt_files; # option files arrayref
   if ( $format eq 'show_variables' ) {
      $vars = parse_show_variables(%args);
   }
   elsif ( $format eq 'mysqld' ) {
      ($vars, $opt_files) = parse_mysqld(%args);
   }
   elsif ( $format eq 'my_print_defaults' ) {
      ($vars, $dupes) = parse_my_print_defaults(%args);
   }
   elsif ( $format eq 'option_file' ) {
      ($vars, $dupes) = parse_option_file(%args);
   }
   else {
      die "Invalid MySQL config format: $format";
   }

   die "Failed to parse MySQL config" unless $vars && keys %$vars;

   if ( $format ne 'show_variables' ) {
      _mimic_show_variables(
         %args,
         format => $format,
         vars   => $vars,
      );
   }

   return (
      format         => $format,
      vars           => $vars,
      option_files   => $opt_files,
      duplicate_vars => $dupes,
   );
}

sub detect_config_output_format {
   my ( %args ) = @_;
   my @required_args = qw(output);
   foreach my $arg ( @required_args ) {
      die "I need a $arg arugment" unless $args{$arg};
   }
   my ($output) = @args{@required_args};

   my $format;
   if (    $output =~ m/\|\s+\w+\s+\|\s+.+?\|/
        || $output =~ m/\*+ \d/
        || $output =~ m/Variable_name:\s+\w+/
        || $output =~ m/Variable_name\s+Value$/m )
   {
      MKDEBUG && _d('show variables format');
      $format = 'show_variables';
   }
   elsif (    $output =~ m/Starts the MySQL database server/
           || $output =~ m/Default options are read from /
           || $output =~ m/^help\s+TRUE /m )
   {
      MKDEBUG && _d('mysqld format');
      $format = 'mysqld';
   }
   elsif ( $output =~ m/^--\w+/m ) {
      MKDEBUG && _d('my_print_defaults format');
      $format = 'my_print_defaults';
   }
   elsif ( $output =~ m/^\s*\[[a-zA-Z]+\]\s*$/m ) {
      MKDEBUG && _d('option file format');
      $format = 'option_file',
   }

   return $format;
}

sub parse_show_variables {
   my ( %args ) = @_;
   my @required_args = qw(output TextResultSetParser);
   foreach my $arg ( @required_args ) {
      die "I need a $arg arugment" unless $args{$arg};
   }
   my ($output, $trp) = @args{@required_args};

   my %config = map {
      $_->{Variable_name} => $_->{Value}
   } @{ $trp->parse($output) };

   return \%config;
}

sub parse_mysqld {
   my ( %args ) = @_;
   my @required_args = qw(output);
   foreach my $arg ( @required_args ) {
      die "I need a $arg arugment" unless $args{$arg};
   }
   my ($output) = @args{@required_args};

   my @opt_files;
   if ( $output =~ m/^Default options are read.+\n/mg ) {
      my ($opt_files) = $output =~ m/\G^(.+)\n/m;
      my %seen;
      my @opt_files = grep { !$seen{$_} } split(' ', $opt_files);
      MKDEBUG && _d('Option files:', @opt_files);
   }
   else {
      MKDEBUG && _d("mysqld help output doesn't list option files");
   }

   if ( $output !~ m/^-+ -+$/mg ) {
      MKDEBUG && _d("mysqld help output doesn't list vars and vals");
      return;
   }

   my $varvals = substr($output, (pos $output) + 1, length $output);

   my ($config, undef) = _parse_varvals(
      $varvals =~ m/\G^(\S+)(.*)\n/mg
   );

   return $config, \@opt_files;
}

sub parse_my_print_defaults {
   my ( %args ) = @_;
   my @required_args = qw(output);
   foreach my $arg ( @required_args ) {
      die "I need a $arg arugment" unless $args{$arg};
   }
   my ($output) = @args{@required_args};

   my ($config, $dupes) = _parse_varvals(
      map { $_ =~ m/^--([^=]+)(?:=(.*))?$/ } split("\n", $output)
   );

   return $config, $dupes;
}

sub parse_option_file {
   my ( %args ) = @_;
   my @required_args = qw(output);
   foreach my $arg ( @required_args ) {
      die "I need a $arg arugment" unless $args{$arg};
   }
   my ($output) = @args{@required_args};

   my ($mysqld_section) = $output =~ m/\[mysqld\](.+?)(?:^\s*\[\w+\]|\Z)/xms;
   die "Failed to parse the [mysqld] section" unless $mysqld_section;

   my ($config, $dupes) = _parse_varvals(
      map  { $_ =~ m/^([^=]+)(?:=(.*))?$/ }
      grep { $_ !~ m/^\s*#/ }  # no # comment lines
      split("\n", $mysqld_section)
   );

   return $config, $dupes;
}

sub _parse_varvals {
   my ( @varvals ) = @_;

   my %config;

   my $duplicate_var = 0;
   my %duplicates;

   my $var;  # current variable (e.g. datadir)
   my $val;  # value for current variable
   ITEM:
   foreach my $item ( @varvals ) {
      if ( $item ) {
         $item =~ s/^\s+//;
         $item =~ s/\s+$//;
      }

      if ( !$var ) {
         $var = $item;

         $var =~ s/-/_/g;

         if ( exists $config{$var} && !$can_be_duplicate{$var} ) {
            MKDEBUG && _d("Duplicate var:", $var);
            $duplicate_var = 1;  # flag on, save all the var's values
         }
      }
      else {
         my $val = $item;
         MKDEBUG && _d("Var:", $var, "val:", $val);

         if ( !defined $val ) {
            $val = '';
         }
         else {
            if ( my ($num, $factor) = $val =~ m/(\d+)([KMGT])b?$/i ) {
               my %factor_for = (
                  k => 1_024,
                  m => 1_048_576,
                  g => 1_073_741_824,
                  t => 1_099_511_627_776,
               );
               $val = $num * $factor_for{lc $factor};
            }
            elsif ( $val =~ m/No default/ ) {
               $val = '';
            }
         }

         if ( $duplicate_var ) {
            push @{$duplicates{$var}}, $config{$var};
            $duplicate_var = 0;  # flag off for next var
         }

         $config{$var} = $val;

         $var = undef;  # next item should be a var
      }
   }

   return \%config, \%duplicates;
}

sub _mimic_show_variables {
   my ( %args ) = @_;
   my @required_args = qw(vars format);
   foreach my $arg ( @required_args ) {
      die "I need a $arg arugment" unless $args{$arg};
   }
   my ($vars, $format) = @args{@required_args};
   
   foreach my $var ( keys %$vars ) {
      if ( $vars->{$var} eq '' ) {
         if ( $format eq 'mysqld' ) {
            if ( $var ne 'log_error' && $var =~ m/^(?:log|skip|ignore)/ ) {
               $vars->{$var} = 'OFF';
            }
         }
         else {
            $vars->{$var} = 'ON';
         }
      }
   }

   return;
}

sub _slurp_file {
   my ( $file ) = @_;
   die "I need a file argument" unless $file;
   MKDEBUG && _d("Reading", $file);
   open my $fh, '<', $file or die "Cannot open $file: $OS_ERROR";
   my $contents = do { local $/ = undef; <$fh> };
   close $fh;
   return $contents;
}

sub _get_version {
   my ( $dbh ) = @_;
   return unless $dbh;
   my $version = $dbh->selectrow_arrayref('SELECT VERSION()')->[0];
   $version =~ s/(\d\.\d{1,2}.\d{1,2})/$1/;
   MKDEBUG && _d('MySQL version', $version);
   return $version;
}


sub has {
   my ( $self, $var ) = @_;
   return exists $self->{vars}->{$var};
}

sub value_of {
   my ( $self, $var ) = @_;
   return unless $var;
   return $self->{vars}->{$var};
}

sub variables {
   my ( $self, %args ) = @_;
   return $self->{vars};
}

sub duplicate_variables {
   my ( $self ) = @_;
   return $self->{duplicate_vars};
}

sub option_files {
   my ( $self ) = @_;
   return $self->{option_files};
}

sub mysql_version {
   my ( $self ) = @_;
   return $self->{mysql_version};
}

sub format {
   my ( $self ) = @_;
   return $self->{format};
}

sub is_active {
   my ( $self ) = @_;
   return $self->{dbh} ? 1 : 0;
}

sub _d {
   my ($package, undef, $line) = caller 0;
   @_ = map { (my $temp = $_) =~ s/\n/\n# /g; $temp; }
        map { defined $_ ? $_ : 'undef' }
        @_;
   print STDERR "# $package:$line $PID ", join(' ', @_), "\n";
}

1;
}
# ###########################################################################
# End MySQLConfig package
# ###########################################################################

# ###########################################################################
# MySQLConfigComparer package
# This package is a copy without comments from the original.  The original
# with comments and its test file can be found in the Bazaar repository at,
#   lib/MySQLConfigComparer.pm
#   t/lib/MySQLConfigComparer.t
# See https://launchpad.net/percona-toolkit for more information.
# ###########################################################################
{
package MySQLConfigComparer;

use strict;
use warnings FATAL => 'all';
use English qw(-no_match_vars);
use constant MKDEBUG => $ENV{MKDEBUG} || 0;

my %alt_val_for = (
   ON    => 1,
   YES   => 1,
   TRUE  => 1,
   OFF   => 0,
   NO    => 0,
   FALSE => 0,
);

sub new {
   my ( $class, %args ) = @_;

   my %ignore_vars = (
      date_format      => 1,
      datetime_format  => 1,
      ft_stopword_file => 1,
      timestamp        => 1,
      time_format      => 1,
      ($args{ignore_variables}
         ? map { $_ => 1 } @{$args{ignore_variables}}
         : ()),
   );

   my %is_numeric = (
      long_query_time => 1, 
      ($args{numeric_variables}
         ? map { $_ => 1 } @{$args{numeric_variables}}
         : ()),
   );

   my %value_is_optional = (
      log_error => 1,
      log_isam  => 1,
      ($args{optional_value_variables}
         ? map { $_ => 1 } @{$args{optional_value_variables}}
         : ()),
   ); 

   my %any_value_is_true = (
      log              => 1,
      log_bin          => 1,
      log_slow_queries => 1,
      ($args{any_value_is_true_variables}
         ? map { $_ => 1 } @{$args{any_value_is_true_variables}}
         : ()),
   );

   my %base_path = (
      character_sets_dir   => 'basedir',
      datadir              => 'basedir',
      general_log_file     => 'datadir',
      language             => 'basedir',
      log_error            => 'datadir',
      pid_file             => 'datadir',
      plugin_dir           => 'basedir',
      slow_query_log_file  => 'datadir',
      socket               => 'datadir',
      ($args{base_paths}
         ? map { $_ => 1 } @{$args{base_paths}}
         : ()),
   );

   my $self = {
      ignore_vars       => \%ignore_vars,
      is_numeric        => \%is_numeric,
      value_is_optional => \%value_is_optional,
      any_value_is_true => \%any_value_is_true,
      base_path         => \%base_path,
   };

   return bless $self, $class;
}

sub diff {
   my ( $self, %args ) = @_;
   my @required_args = qw(configs);
   foreach my $arg( @required_args ) {
      die "I need a $arg argument" unless $args{$arg};
   }
   my ($configs) = @args{@required_args};

   if ( @$configs < 2 ) {
      MKDEBUG && _d("Less than two MySQLConfig objects; nothing to compare");
      return;
   }

   my $base_path         = $self->{base_path};
   my $is_numeric        = $self->{is_numeric};
   my $any_value_is_true = $self->{any_value_is_true};
   my $value_is_optional = $self->{value_is_optional};

   my $config0     = $configs->[0];
   my $last_config = @$configs - 1;
   my $vars        = $self->_get_shared_vars(%args);

   my $diffs;
   VARIABLE:
   foreach my $var ( @$vars ) {
      my $is_dir = $var =~ m/dir$/ || $var eq 'language';
      my $val0   = $self->_normalize_value(  # config0 value
         value        => $config0->value_of($var),
         is_directory => $is_dir,
         base_path    => $config0->value_of($base_path->{$var}) || "",
      );

      eval {
         CONFIG:
         foreach my $configN ( @$configs[1..$last_config] ) {
            my $valN = $self->_normalize_value(  # configN value
               value        => $configN->value_of($var),
               is_directory => $is_dir,
               base_path    => $configN->value_of($base_path->{$var}) || "",
            );

            if ( $is_numeric->{$var} ) {
               next CONFIG if $val0 == $valN;
            }
            else {
               next CONFIG if $val0 eq $valN;

               if ( $config0->format() ne $configN->format() ) {
                  if ( $any_value_is_true->{$var} ) {
                     next CONFIG if $val0 && $valN;
                  }
                  if ( $value_is_optional->{$var} ) {
                     next CONFIG if (!$val0 && $valN) || ($val0 && !$valN);
                  }
               }
            }

            MKDEBUG && _d("Different", $var, "values:", $val0, $valN);
            $diffs->{$var} = [ map { $_->value_of($var) } @$configs ];
            last CONFIG;
         }  # CONFIG
      };
      if ( $EVAL_ERROR ) {
         my $vals = join(', ',
            map {
               my $val = $_->value_of($var);
               defined $val ? $val : 'undef'
            } @$configs);
         warn "Comparing $var values ($vals) caused an error: $EVAL_ERROR";
      }
   }  # VARIABLE

   return $diffs;
}

sub missing {
   my ( $self, %args ) = @_;
   my @required_args = qw(configs);
   foreach my $arg( @required_args ) {
      die "I need a $arg argument" unless $args{$arg};
   }
   my ($configs) = @args{@required_args};

   if ( @$configs < 2 ) {
      MKDEBUG && _d("Less than two MySQLConfig objects; nothing to compare");
      return;
   }

   my %vars = map { $_ => 1 } map { keys %{$_->variables()} } @$configs;
   my $missing;
   foreach my $var ( keys %vars ) {
      my $n_configs_having_var = grep { $_->has($var) } @$configs;
      if ( $n_configs_having_var < @$configs ) {
         $missing->{$var} = [ map { $_->has($var) ? 1 : 0 } @$configs ];
      }
   }

   return $missing;
}

sub _normalize_value {
   my ( $self, %args ) = @_;
   my ($val, $is_dir, $base_path) = @args{qw(value is_directory base_path)};

   $val = defined $val ? $val : '';
   $val = $alt_val_for{$val} if exists $alt_val_for{$val};

   if ( $val ) {
      if ( $is_dir ) {
         $val .= '/' unless $val =~ m/\/$/;
      }
      if ( $base_path && $val !~ m/^\// ) {
         $val =~ s/^\.?(.+)/$base_path\/$1/;  # prepend base path
         $val =~ s/\/{2,}/\//g;               # make redundant // single /
      }
   }
   return $val;
}

sub _get_shared_vars {
   my ( $self, %args ) = @_;
   my ($configs)   = @args{qw(configs)};
   my $ignore_vars = $self->{ignore_vars};
   my $config0     = $configs->[0];
   my $last_config = @$configs - 1;
   my @vars
      = grep { !$ignore_vars->{$_} }
      map {
         my $config = $_;
         my $vars   = $config->variables();
         grep { $config0->has($_); } keys %$vars;
      }  @$configs[1..$last_config];
   return \@vars;
}

sub _d {
   my ($package, undef, $line) = caller 0;
   @_ = map { (my $temp = $_) =~ s/\n/\n# /g; $temp; }
        map { defined $_ ? $_ : 'undef' }
        @_;
   print STDERR "# $package:$line $PID ", join(' ', @_), "\n";
}

1;
}
# ###########################################################################
# End MySQLConfigComparer package
# ###########################################################################

# ###########################################################################
# ReportFormatter package
# This package is a copy without comments from the original.  The original
# with comments and its test file can be found in the Bazaar repository at,
#   lib/ReportFormatter.pm
#   t/lib/ReportFormatter.t
# See https://launchpad.net/percona-toolkit for more information.
# ###########################################################################
{
package ReportFormatter;

use strict;
use warnings FATAL => 'all';
use English qw(-no_match_vars);
use constant MKDEBUG => $ENV{MKDEBUG} || 0;

use List::Util qw(min max);
use POSIX qw(ceil);

eval { require Term::ReadKey };
my $have_term = $EVAL_ERROR ? 0 : 1;

sub new {
   my ( $class, %args ) = @_;
   my @required_args = qw();
   foreach my $arg ( @required_args ) {
      die "I need a $arg argument" unless $args{$arg};
   }
   my $self = {
      underline_header     => 1,
      line_prefix          => '# ',
      line_width           => 78,
      column_spacing       => ' ',
      extend_right         => 0,
      truncate_line_mark   => '...',
      column_errors        => 'warn',
      truncate_header_side => 'left',
      strip_whitespace     => 1,
      %args,              # args above can be overriden, args below cannot
      n_cols              => 0,
   };

   if ( ($self->{line_width} || '') eq 'auto' ) {
      die "Cannot auto-detect line width because the Term::ReadKey module "
         . "is not installed" unless $have_term;
      ($self->{line_width}) = GetTerminalSize();
   }
   MKDEBUG && _d('Line width:', $self->{line_width});

   return bless $self, $class;
}

sub set_title {
   my ( $self, $title ) = @_;
   $self->{title} = $title;
   return;
}

sub set_columns {
   my ( $self, @cols ) = @_;
   my $min_hdr_wid = 0;  # check that header fits on line
   my $used_width  = 0;
   my @auto_width_cols;

   for my $i ( 0..$#cols ) {
      my $col      = $cols[$i];
      my $col_name = $col->{name};
      my $col_len  = length $col_name;
      die "Column does not have a name" unless defined $col_name;

      if ( $col->{width} ) {
         $col->{width_pct} = ceil(($col->{width} * 100) / $self->{line_width});
         MKDEBUG && _d('col:', $col_name, 'width:', $col->{width}, 'chars =',
            $col->{width_pct}, '%');
      }

      if ( $col->{width_pct} ) {
         $used_width += $col->{width_pct};
      }
      else {
         MKDEBUG && _d('Auto width col:', $col_name);
         $col->{auto_width} = 1;
         push @auto_width_cols, $i;
      }

      $col->{truncate}        = 1 unless defined $col->{truncate};
      $col->{truncate_mark}   = '...' unless defined $col->{truncate_mark};
      $col->{truncate_side} ||= 'right';
      $col->{undef_value}     = '' unless defined $col->{undef_value};

      $col->{min_val} = 0;
      $col->{max_val} = 0;

      $min_hdr_wid        += $col_len;
      $col->{header_width} = $col_len;

      $col->{right_most} = 1 if $i == $#cols;

      push @{$self->{cols}}, $col;
   }

   $self->{n_cols} = scalar @cols;

   if ( ($used_width || 0) > 100 ) {
      die "Total width_pct for all columns is >100%";
   }

   if ( @auto_width_cols ) {
      my $wid_per_col = int((100 - $used_width) / scalar @auto_width_cols);
      MKDEBUG && _d('Line width left:', (100-$used_width), '%;',
         'each auto width col:', $wid_per_col, '%');
      map { $self->{cols}->[$_]->{width_pct} = $wid_per_col } @auto_width_cols;
   }

   $min_hdr_wid += ($self->{n_cols} - 1) * length $self->{column_spacing};
   MKDEBUG && _d('min header width:', $min_hdr_wid);
   if ( $min_hdr_wid > $self->{line_width} ) {
      MKDEBUG && _d('Will truncate headers because min header width',
         $min_hdr_wid, '> line width', $self->{line_width});
      $self->{truncate_headers} = 1;
   }

   return;
}

sub add_line {
   my ( $self, @vals ) = @_;
   my $n_vals = scalar @vals;
   if ( $n_vals != $self->{n_cols} ) {
      $self->_column_error("Number of values $n_vals does not match "
         . "number of columns $self->{n_cols}");
   }
   for my $i ( 0..($n_vals-1) ) {
      my $col   = $self->{cols}->[$i];
      my $val   = defined $vals[$i] ? $vals[$i] : $col->{undef_value};
      if ( $self->{strip_whitespace} ) {
         $val =~ s/^\s+//g;
         $val =~ s/\s+$//;
         $vals[$i] = $val;
      }
      my $width = length $val;
      $col->{min_val} = min($width, ($col->{min_val} || $width));
      $col->{max_val} = max($width, ($col->{max_val} || $width));
   }
   push @{$self->{lines}}, \@vals;
   return;
}

sub get_report {
   my ( $self, %args ) = @_;

   $self->_calculate_column_widths();
   $self->_truncate_headers() if $self->{truncate_headers};
   $self->_truncate_line_values(%args);

   my @col_fmts = $self->_make_column_formats();
   my $fmt      = ($self->{line_prefix} || '')
                . join($self->{column_spacing}, @col_fmts);
   MKDEBUG && _d('Format:', $fmt);

   (my $hdr_fmt = $fmt) =~ s/%([^-])/%-$1/g;

   my @lines;
   push @lines, sprintf "$self->{line_prefix}$self->{title}" if $self->{title};
   push @lines, $self->_truncate_line(
         sprintf($hdr_fmt, map { $_->{name} } @{$self->{cols}}),
         strip => 1,
         mark  => '',
   );

   if ( $self->{underline_header} ) {
      my @underlines = map { '=' x $_->{print_width} } @{$self->{cols}};
      push @lines, $self->_truncate_line(
         sprintf($fmt, @underlines),
         mark  => '',
      );
   }

   push @lines, map {
      my $vals = $_;
      my $i    = 0;
      my @vals = map {
            defined $_ ? $_ : $self->{cols}->[$i++]->{undef_value}
      } @$vals;
      my $line = sprintf($fmt, @vals);
      if ( $self->{extend_right} ) {
         $line;
      }
      else {
         $self->_truncate_line($line);
      }
   } @{$self->{lines}};

   return join("\n", @lines) . "\n";
}

sub truncate_value {
   my ( $self, $col, $val, $width, $side ) = @_;
   return $val if length $val <= $width;
   return $val if $col->{right_most} && $self->{extend_right};
   $side  ||= $col->{truncate_side};
   my $mark = $col->{truncate_mark};
   if ( $side eq 'right' ) {
      $val  = substr($val, 0, $width - length $mark);
      $val .= $mark;
   }
   elsif ( $side eq 'left') {
      $val = $mark . substr($val, -1 * $width + length $mark);
   }
   else {
      MKDEBUG && _d("I don't know how to", $side, "truncate values");
   }
   return $val;
}

sub _calculate_column_widths {
   my ( $self ) = @_;

   my $extra_space = 0;
   foreach my $col ( @{$self->{cols}} ) {
      my $print_width = int($self->{line_width} * ($col->{width_pct} / 100));

      MKDEBUG && _d('col:', $col->{name}, 'width pct:', $col->{width_pct},
         'char width:', $print_width,
         'min val:', $col->{min_val}, 'max val:', $col->{max_val});

      if ( $col->{auto_width} ) {
         if ( $col->{min_val} && $print_width < $col->{min_val} ) {
            MKDEBUG && _d('Increased to min val width:', $col->{min_val});
            $print_width = $col->{min_val};
         }
         elsif ( $col->{max_val} &&  $print_width > $col->{max_val} ) {
            MKDEBUG && _d('Reduced to max val width:', $col->{max_val});
            $extra_space += $print_width - $col->{max_val};
            $print_width  = $col->{max_val};
         }
      }

      $col->{print_width} = $print_width;
      MKDEBUG && _d('print width:', $col->{print_width});
   }

   MKDEBUG && _d('Extra space:', $extra_space);
   while ( $extra_space-- ) {
      foreach my $col ( @{$self->{cols}} ) {
         if (    $col->{auto_width}
              && (    $col->{print_width} < $col->{max_val}
                   || $col->{print_width} < $col->{header_width})
         ) {
            $col->{print_width}++;
         }
      }
   }

   return;
}

sub _truncate_headers {
   my ( $self, $col ) = @_;
   my $side = $self->{truncate_header_side};
   foreach my $col ( @{$self->{cols}} ) {
      my $col_name    = $col->{name};
      my $print_width = $col->{print_width};
      next if length $col_name <= $print_width;
      $col->{name}  = $self->truncate_value($col, $col_name, $print_width, $side);
      MKDEBUG && _d('Truncated hdr', $col_name, 'to', $col->{name},
         'max width:', $print_width);
   }
   return;
}

sub _truncate_line_values {
   my ( $self, %args ) = @_;
   my $n_vals = $self->{n_cols} - 1;
   foreach my $vals ( @{$self->{lines}} ) {
      for my $i ( 0..$n_vals ) {
         my $col   = $self->{cols}->[$i];
         my $val   = defined $vals->[$i] ? $vals->[$i] : $col->{undef_value};
         my $width = length $val;

         if ( $col->{print_width} && $width > $col->{print_width} ) {
            if ( !$col->{truncate} ) {
               $self->_column_error("Value '$val' is too wide for column "
                  . $col->{name});
            }

            my $callback    = $args{truncate_callback};
            my $print_width = $col->{print_width};
            $val = $callback ? $callback->($col, $val, $print_width)
                 :             $self->truncate_value($col, $val, $print_width);
            MKDEBUG && _d('Truncated val', $vals->[$i], 'to', $val,
               '; max width:', $print_width);
            $vals->[$i] = $val;
         }
      }
   }
   return;
}

sub _make_column_formats {
   my ( $self ) = @_;
   my @col_fmts;
   my $n_cols = $self->{n_cols} - 1;
   for my $i ( 0..$n_cols ) {
      my $col = $self->{cols}->[$i];

      my $width = $col->{right_most} && !$col->{right_justify} ? ''
                : $col->{print_width};

      my $col_fmt  = '%' . ($col->{right_justify} ? '' : '-') . $width . 's';
      push @col_fmts, $col_fmt;
   }
   return @col_fmts;
}

sub _truncate_line {
   my ( $self, $line, %args ) = @_;
   my $mark = defined $args{mark} ? $args{mark} : $self->{truncate_line_mark};
   if ( $line ) {
      $line =~ s/\s+$// if $args{strip};
      my $len  = length($line);
      if ( $len > $self->{line_width} ) {
         $line  = substr($line, 0, $self->{line_width} - length $mark);
         $line .= $mark if $mark;
      }
   }
   return $line;
}

sub _column_error {
   my ( $self, $err ) = @_;
   my $msg = "Column error: $err";
   $self->{column_errors} eq 'die' ? die $msg : warn $msg;
   return;
}

sub _d {
   my ($package, undef, $line) = caller 0;
   @_ = map { (my $temp = $_) =~ s/\n/\n# /g; $temp; }
        map { defined $_ ? $_ : 'undef' }
        @_;
   print STDERR "# $package:$line $PID ", join(' ', @_), "\n";
}

1;
}
# ###########################################################################
# End ReportFormatter package
# ###########################################################################

# ###########################################################################
# This is a combination of modules and programs in one -- a runnable module.
# http://www.perl.com/pub/a/2006/07/13/lightning-articles.html?page=last
# Or, look it up in the Camel book on pages 642 and 643 in the 3rd edition.
#
# Check at the end of this package for the call to main() which actually runs
# the program.
# ###########################################################################
package pt_config_diff;

use strict;
use warnings FATAL => 'all';
use English qw(-no_match_vars);
use Data::Dumper;
$Data::Dumper::Indent    = 1;
$Data::Dumper::Sortkeys  = 1;
$Data::Dumper::Quotekeys = 0;

use constant MKDEBUG => $ENV{MKDEBUG} || 0;

sub main {
   @ARGV = @_;  # set global ARGV for this package

   # ########################################################################
   # Get configuration information.
   # ########################################################################
   my $o = new OptionParser();
   $o->get_specs();
   $o->get_opts();

   my $dp = $o->DSNParser();
   $dp->prop('set-vars', $o->get('set-vars'));

   if ( !$o->get('help') ) {
      if ( @ARGV < 1 ) {
        $o->save_error("Specify at least one file or DSN on the command line");
      }
   }

   $o->usage_or_errors();

   # #########################################################################
   # Make common modules.
   # #########################################################################
   my $trp         = new TextResultSetParser();
   my $config_cmp  = new MySQLConfigComparer(
      ignore_variables => $o->get('ignore-variables'),
   );
   my %common_modules = (
      DSNParser           => $dp,
      OptionParser        => $o,
      MySQLConfigComparer => $config_cmp,
      TextResultSetParser => $trp,
   );

   # #########################################################################
   # Make MySQLConfig objs for each FILE|DSN.
   # #########################################################################
   my $dsn_defaults = $dp->parse_options($o);
   my $last_dsn;
   my @configs;       # MySQLConfig objects
   my @config_names;  # Human-readable names for those ^ objs
   foreach my $config_src ( @ARGV ) {
      if ( -f $config_src ) {
         MKDEBUG && _d('Config source', $config_src, 'is a file');
         push @configs, new MySQLConfig(
            file => $config_src,
            %common_modules,
         );
         push @config_names, $config_src;  # filename
      }
      else {
         MKDEBUG && _d('Config source', $config_src, 'is a DSN');
         my $dsn = $dp->parse($config_src, $last_dsn, $dsn_defaults);
         my $dbh = $dp->get_dbh($dp->get_cxn_params($dsn), {AutoCommit => 1});
         $dp->fill_in_dsn($dbh, $dsn);
         $last_dsn = $dsn;

         push @configs, new MySQLConfig(
            dbh => $dbh,
            %common_modules,
         );
         my $config_name = ($dsn->{h} || $dsn->{S} || $dsn->{F})
                         . ($dsn->{P} ? ":$dsn->{P}" : '');
         push @config_names, $config_name;
      }
   }

   # ########################################################################
   # Daemonize now that everything is setup and ready to work.
   # ########################################################################
   my $daemon;
   if ( $o->get('daemonize') ) {
      $daemon = new Daemon(o=>$o);
      $daemon->daemonize();
      MKDEBUG && _d('I am a daemon now');
   }
   elsif ( $o->get('pid') ) {
      # We're not daemoninzing, it just handles PID stuff.
      $daemon = new Daemon(o=>$o);
      $daemon->make_PID_file();
   }

   # #########################################################################
   # Diff the given configs.
   # #########################################################################
   my $report;
   my $truncate_callback;
   if ( $o->get('report') ) {
      $report = new ReportFormatter(
         line_prefix => '',
         line_width  => $o->get('report-width'),
      ); 
      $report->set_columns(
         { name => 'Variable', width=>25, },
         map { { name => $_ } } @config_names,
      );

      # This is difficult.  Ideally, we want to know which var this
      # val applies to (i.e. first column, same row).  But that's
      # not how ReportFormatter works.  Plus, even if we truncate a
      # path on the left side, that might be where the difference is.
      # So there's no easy solution here.
      # $truncate_callback = sub {
      # };
   }

   MKDEBUG && _d("Comparing", scalar @configs, "configs");
   my $diffs   = $config_cmp->diff(configs=>\@configs);
   my $n_diffs = scalar keys %$diffs;
   MKDEBUG && _d($n_diffs, "differences found:", Dumper($diffs));
   if ( $n_diffs ) {
      if ( $o->get('report') ) {
         foreach my $var ( sort keys %$diffs ) {
            $report->add_line($var, @{$diffs->{$var}});
         }
         $report->set_title(
            "$n_diffs config difference" . ($n_diffs > 1 ? 's' : ''));
         print $report->get_report();
      }
      return 1;
   }

   # No differences.
   return 0;
}

# ##########################################################################
# Subroutines
# ##########################################################################

sub _d {
   my ($package, undef, $line) = caller 0;
   @_ = map { (my $temp = $_) =~ s/\n/\n# /g; $temp; }
        map { defined $_ ? $_ : 'undef' }
        @_;
   print STDERR "# $package:$line $PID ", join(' ', @_), "\n";
}

# ############################################################################
# Run the program.
# ############################################################################
if ( !caller ) { exit main(@ARGV); }

1; # Because this is a module as well as a script.

# ############################################################################
# Documentation
# ############################################################################

=pod

=head1 NAME

pt-config-diff - Diff MySQL configuration files and server variables.

=head1 SYNOPSIS

Usage: pt-config-diff [OPTION...] CONFIG CONFIG [CONFIG...]

pt-config-diff diffs MySQL configuration files and server variables.
CONFIG can be a filename or a DSN.  At least two CONFIG sources must be given.
Like standard Unix diff, there is no output if there are no differences.

Diff host1 config from SHOW VARIABLES against host2:

  pt-config-diff h=host1 h=host2

Diff config from [mysqld] section in my.cnf against host1 config:

  pt-config-diff /etc/my.cnf h=host1

Diff the [mysqld] section of two option files:

   pt-config-diff /etc/my-small.cnf /etc/my-large.cnf

=head1 RISKS

The following section is included to inform users about the potential risks,
whether known or unknown, of using this tool.  The two main categories of risks
are those created by the nature of the tool (e.g. read-only tools vs. read-write
tools) and those created by bugs.

pt-config-diff reads MySQL's configuration and examines it and is thus very
low risk.

At the time of this release there are no known bugs that pose a serious risk.

The authoritative source for updated information is always the online issue
tracking system.  Issues that affect this tool will be marked as such.  You can
see a list of such issues at the following URL:
L<http://www.percona.com/bugs/pt-config-diff>.

See also L<"BUGS"> for more information on filing bugs and getting help.

=head1 DESCRIPTION

pt-config-diff diffs MySQL configurations by examining the values of server
system variables from two or more CONFIG sources specified on the command
line.  A CONFIG source can be a DSN or a filename containing the output of
C<mysqld --help --verbose>, C<my_print_defaults>, C<SHOW VARIABLES>, or
an option file (e.g. my.cnf).

For each DSN CONFIG, pt-config-diff connects to MySQL and gets variables
and values by executing C<SHOW /*!40103 GLOBAL*/ VARIABLES>.  This is
an "active config" because it shows what server values MySQL is
actively (currently) running with.

Only variables that all CONFIG sources have are compared because if a
variable is not present then we cannot know or safely guess its value.
For example, if you compare an option file (e.g. my.cnf) to an active config
(i.e. SHOW VARIABLES from a DSN CONFIG), the option file will probably
only have a few variables, whereas the active config has every variable.
Only values of the variables present in both configs are compared.

Option file and DSN configs provide the best results.

=head1 OUTPUT

There is no output when there are no differences.  When there are differences,
pt-config-diff prints a report to STDOUT that looks similar to the following:

  2 config differences
  Variable                  my.master.cnf   my.slave.cnf
  ========================= =============== ===============
  datadir                   /tmp/12345/data /tmp/12346/data
  port                      12345           12346

Comparing MySQL variables is difficult because there are many variations and
subtleties across the many versions and distributions of MySQL.  When a
comparison fails, the tool prints a warning to STDERR, such as the following:

  Comparing log_error values (mysqld.log, /tmp/12345/data/mysqld.log)
  caused an error: Argument "/tmp/12345/data/mysqld.log" isn't numeric
  in numeric eq (==) at ./pt-config-diff line 2311.

Please report these warnings so the comparison functions can be improved.

=head1 EXIT STATUS

pt-config-diff exits with a zero exit status when there are no differences, and
1 if there are.

=head1 OPTIONS

This tool accepts additional command-line arguments.  Refer to the
L<"SYNOPSIS"> and usage information for details.

=over

=item --ask-pass

Prompt for a password when connecting to MySQL.

=item --charset

short form: -A; type: string

Default character set.  If the value is utf8, sets Perl's binmode on
STDOUT to utf8, passes the mysql_enable_utf8 option to DBD::mysql, and
runs SET NAMES UTF8 after connecting to MySQL.  Any other value sets
binmode on STDOUT without the utf8 layer, and runs SET NAMES after
connecting to MySQL.

=item --config

type: Array

Read this comma-separated list of config files; if specified, this must be the
first option on the command line.  (This option does not specify a CONFIG;
it's equivalent to C<--defaults-file>.)

=item --daemonize

Fork to the background and detach from the shell.  POSIX
operating systems only.

=item --defaults-file

short form: -F; type: string

Only read mysql options from the given file.  You must give an absolute
pathname.

=item --help

Show help and exit.

=item --host

short form: -h; type: string

Connect to host.

=item --ignore-variables

type: array

Ignore, do not compare, these variables.

=item --password

short form: -p; type: string

Password to use for connection.

=item --pid

type: string

Create the given PID file when daemonized.  The file contains the process
ID of the daemonized instance.  The PID file is removed when the
daemonized instance exits.  The program checks for the existence of the
PID file when starting; if it exists and the process with the matching PID
exists, the program exits.

=item --port

short form: -P; type: int

Port number to use for connection.

=item --[no]report

default: yes

Print the MySQL config diff report to STDOUT.  If you just want to check
if the given configs are different or not by examining the tool's exit
status, then specify C<--no-report> to suppress the report.

=item --report-width

type: int; default: 78

Truncate report lines to this many characters.  Since some variable values can
be long, or when comparing multiple configs, it may help to increase the
report width so values are not truncated beyond readability.

=item --set-vars

type: string; default: wait_timeout=10000

Set these MySQL variables.  Immediately after connecting to MySQL, this string
will be appended to SET and executed.

=item --socket

short form: -S; type: string

Socket file to use for connection.

=item --user

short form: -u; type: string

MySQL user if not current user.

=item --version

Show version and exit.

=back

=head1 DSN OPTIONS

These DSN options are used to create a DSN.  Each option is given like
C<option=value>.  The options are case-sensitive, so P and p are not the
same option.  There cannot be whitespace before or after the C<=> and
if the value contains whitespace it must be quoted.  DSN options are
comma-separated.  See the L<percona-toolkit> manpage for full details.

=over

=item * A

dsn: charset; copy: yes

Default character set.

=item * D

dsn: database; copy: yes

Default database.

=item * F

dsn: mysql_read_default_file; copy: yes

Only read default options from the given file

=item * h

dsn: host; copy: yes

Connect to host.

=item * p

dsn: password; copy: yes

Password to use when connecting.

=item * P

dsn: port; copy: yes

Port number to use for connection.

=item * S

dsn: mysql_socket; copy: yes

Socket file to use for connection.

=item * u

dsn: user; copy: yes

User for login if not current user.

=back

=head1 ENVIRONMENT

The environment variable C<PTDEBUG> enables verbose debugging output to STDERR.
To enable debugging and capture all output to a file, run the tool like:

   PTDEBUG=1 pt-config-diff ... > FILE 2>&1

Be careful: debugging output is voluminous and can generate several megabytes
of output.

=head1 SYSTEM REQUIREMENTS

You need Perl, DBI, DBD::mysql, and some core packages that ought to be
installed in any reasonably new version of Perl.

=head1 BUGS

For a list of known bugs, see L<http://www.percona.com/bugs/pt-config-diff>.

Please report bugs at L<https://bugs.launchpad.net/percona-toolkit>.
Include the following information in your bug report:

=over

=item * Complete command-line used to run the tool

=item * Tool L<"--version">

=item * MySQL version of all servers involved

=item * Output from the tool including STDERR

=item * Input files (log/dump/config files, etc.)

=back

If possible, include debugging output by running the tool with C<PTDEBUG>;
see L<"ENVIRONMENT">.

=head1 DOWNLOADING

Visit L<http://www.percona.com/software/percona-toolkit/> to download the
latest release of Percona Toolkit.  Or, get the latest release from the
command line:

   wget percona.com/get/percona-toolkit.tar.gz

   wget percona.com/get/percona-toolkit.rpm

   wget percona.com/get/percona-toolkit.deb

You can also get individual tools from the latest release:

   wget percona.com/get/TOOL

Replace C<TOOL> with the name of any tool.

=head1 AUTHORS

Baron Schwartz and Daniel Nichter

=head1 ABOUT PERCONA TOOLKIT

This tool is part of Percona Toolkit, a collection of advanced command-line
tools developed by Percona for MySQL support and consulting.  Percona Toolkit
was forked from two projects in June, 2011: Maatkit and Aspersa.  Those
projects were created by Baron Schwartz and developed primarily by him and
Daniel Nichter, both of whom are employed by Percona.  Visit
L<http://www.percona.com/software/> for more software developed by Percona.

=head1 COPYRIGHT, LICENSE, AND WARRANTY

This program is copyright 2011 Percona Inc.
Feedback and improvements are welcome.

THIS PROGRAM IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation, version 2; OR the Perl Artistic License.  On UNIX and similar
systems, you can issue `man perlgpl' or `man perlartistic' to read these
licenses.

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

=head1 VERSION

pt-config-diff 1.0.1

=cut