#!/usr/bin/perl
#
# $Id: my.restart,v 1.14 2013/08/14 18:06:31 erik5 Exp $

=head1 my.restart 

To restart all daemons at once just:

  % ./my.restart -all

To restart a specific daemon, give a server
name as an argument:

  % ./my.restart db49b.pair.com

=cut

use strict;

use Proc::Daemon;
use Getopt::Long;

use lib '/usr/pair/perl';
use Pair::DBServer::Conf qw(user_cnf_info server_cnf_info);
use Pair::Paths qw($PS $GREP $MYSQLD);
use Pair::Serverinfo 'service_enabled';
use Pair::Pidfile;

my $PIDFILE = '/etc/my.restart.pid';
Pair::Pidfile::maintain_pidfile($PIDFILE);

my %opt;
GetOptions (\%opt,"all|a","quiet|q","kill|k");

# Loop Settings
my $MAX_SLEEP = 600;
my $SLEEP_PER = 5;

my $SERVER = &server_cnf_info || die;
my $DAEMONS = grep(/^MYSQLD\d+$/,keys %$SERVER);

service_enabled('MYSQL') or die "MySQL not enabled!\n";

$opt{kill} = 1 if $0 =~ /kill/;
$opt{all} = 1 if $DAEMONS == 0;

#restart specific daemon
if (@ARGV) { 
    my $socket = $SERVER->{$ARGV[0]};
    my ($conf_num) = ($socket =~ /sock(\d+)/i);
    die "Unable to determine config file\n" unless $conf_num;

    #kill current daemon if running
    my $pid = &get_pid("my$conf_num.cnf");
    if ($pid >= 2) { 
        kill('TERM',$pid) if $pid > 1;
        sleep($SLEEP_PER);
    } 
    if (&get_pid("my$conf_num.cnf")) {
      warn "Failed to exit\n" unless $opt{quiet};
      exit;
    }
    unless ( $opt{kill} || !service_enabled('MYSQL') ) {
      Proc::Daemon::Init if $opt{quiet};
      system("$MYSQLD --defaults-file=/etc/my$conf_num\.cnf &");
      unless ($opt{quiet}) {
        sleep 1;
        print &get_pid("my$conf_num\.cnf") ? "Restart Succeeded\n"
              : "Restart Failed!\n"; 
      }
    }
    exit;
} 

unless ($opt{all} or $opt{kill}) {
    print "ERROR: You must specify a specific daemon, or use the '-all' option.\n";
    exit;
}

#kill all mysqld`s
my @ps = split(/\n/,`$PS auxww | $GREP mysqld | $GREP -v grep`);
foreach (@ps) { 
   my ($pid) = (/^mysql\s+(\d+)\s+/);
   kill('TERM',$pid) if $pid > 1;
}     

#sleep waiting for them to exit
my $slept;
while ($slept < $MAX_SLEEP) {
    last unless &get_pid("mysqld"); 
    $slept += sleep($SLEEP_PER);
    print "Waiting to exit...$slept\n" unless $opt{quiet}; 
}  

if (&get_pid("mysqld")) {
  warn "Error. Current mysqld's haven't died yet\n" unless $opt{quiet};
  exit;
}

unless ( $opt{kill} || !service_enabled('MYSQL') ) {
  #restart all in config file
  my @daemons = grep /MYSQLD\d*$/i, keys %$SERVER;
  if (@daemons) {
      foreach my $d (@daemons) {
          my ($num) = ($d =~ /MYSQLD(\d+)/i);
          my $conf = "my$num.cnf";
          Proc::Daemon::Init if $opt{quiet};
          system("$MYSQLD --defaults-file=/etc/$conf &")
      }
      exit;
  } 
  
  #restart default 
  Proc::Daemon::Init if $opt{quiet};
  system("$MYSQLD --defaults-file=/etc/my.cnf &");
}

sub get_pid {
  my $find = shift;

  open(PS,"$PS auxww | $GREP $find | $GREP -v grep|") || 
       return undef;
  my ($pid) = (<PS> =~ /^mysql\s+(\d+)\s/);
  close(PS);
  return $pid || undef;
}