Author: fapeeler
Date: Wed Jul 14 20:30:19 2010
New Revision: 964187
URL: http://svn.apache.org/viewvc?rev=964187&view=rev
Log:
VCL-149
added semaphore lock on /var/lock/subsys/vcld file in the daemonize routine
if a running vcld process is active and attempts to start a second process will
not succeed
Modified:
incubator/vcl/trunk/managementnode/bin/vcld
Modified: incubator/vcl/trunk/managementnode/bin/vcld
URL:
http://svn.apache.org/viewvc/incubator/vcl/trunk/managementnode/bin/vcld?rev=964187&r1=964186&r2=964187&view=diff
==============================================================================
--- incubator/vcl/trunk/managementnode/bin/vcld (original)
+++ incubator/vcl/trunk/managementnode/bin/vcld Wed Jul 14 20:30:19 2010
@@ -774,16 +774,34 @@ sub daemonize {
chdir '/' or die "Can't chdir to /: $!";
defined(my $pid = fork) or die "Can't fork $!";
exit if $pid;
- print "Created VCL daemon process: $$\n";
- setsid or die "Can't start a new session: $!";
- open STDIN, '/dev/null' or die "Can't read /dev/null $!";
- open STDOUT, ">>$LOGFILE" or die "Can't write $LOGFILE $!";
- open STDERR, ">>$LOGFILE" or die "Can't write $LOGFILE $!";
- setsid or die "Can't start a new session: $!";
- umask 0;
- open(PIDFILE, ">" . $PIDFILE) or notify($ERRORS{'WARNING'}, $LOGFILE,
"unable to open PID file: $PIDFILE, $!"); # so I can kill myself easily
- print PIDFILE $$;
- close(PIDFILE);
+
+ #Create EX lock on lockfile
+ my $subsys_lock = "/var/lock/subsys/$PROCESSNAME";
+ sysopen(LOCKFILE, $subsys_lock, O_RDONLY | O_CREAT ) or die "unable to
open lock file: $PIDFILE \n";
+
+ unless(flock(LOCKFILE, LOCK_EX|LOCK_NB)){
+ #write to log file
+ notify($ERRORS{'WARNING'}, $LOGFILE, " An process instance of
$PROCESSNAME is already running ");
+ # print to STDERR
+ print STDERR "\nFailed to start.\n\nAn instance of
$PROCESSNAME is already running\n\n";
+ exit;
+ }
+
+ umask 0;
+ setsid or die "Can't start a new session: $!";
+
+ # write pid to pidfile
+ open(PIDFILE, ">" . $PIDFILE) or notify($ERRORS{'WARNING'}, $LOGFILE,
"unable to open PID file: $PIDFILE, $!");
+ print PIDFILE $$ ;
+ close(PIDFILE);
+
+ #Redirect STDIN,STDOUT,STDERR
+ open STDIN, '/dev/null' or die "Can't read /dev/null $!";
+ open STDOUT, ">>$LOGFILE" or die "Can't write $LOGFILE $!";
+ open STDERR, ">>$LOGFILE" or die "Can't write $LOGFILE $!";
+
+ print "Created VCL daemon process: $$\n";
+
} ## end sub daemonize
#/////////////////////////////////////////////////////////////////////////////
