Class: Arrow::Session::PosixLock

Inherits:
Lock show all
Defined in:
lib/arrow/session/posixlock.rb

Overview

The Arrow::Session::PosixLock class, a derivative of Arrow::Session::Lock. This lock type uses the ‘posixlock’ library (raa.ruby-lang.org/project/posixlock/).

VCS Id

$Id$

Authors

Please see the file LICENSE in the top-level directory for licensing details.

Constant Summary collapse

DefaultLockDir =

The path to the default lockdir

'/tmp'
LockfileFormat =

The format string that will be used for the name of the lock file. The first ‘%s’ will be replaced with a sanitized version of the session id.

"arrow-session-%s.plock"
FileMode =

The mode to open the lockfile in

File::CREAT|File::RDWR

Constants inherited from Lock

Lock::READ, Lock::UNLOCKED, Lock::WRITE

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Lock

create, derivativeDirs, #locked?, #read_lock, #read_locked?, #read_unlock, #release_all_locks, #with_read_lock, #with_write_lock, #write_lock, #write_locked?, #write_unlock

Methods inherited from Object

deprecate_class_method, deprecate_method, inherited

Constructor Details

#initialize(uri, id) ⇒ PosixLock

Create a new Arrow::Session::FileLock object.



73
74
75
76
77
78
79
80
81
 
# File 'lib/arrow/session/posixlock.rb', line 73

def initialize( uri, id )
  @lockDir = uri.path || DefaultLockDir
  super

  File.mkpath( @lockDir )
  @filename = File.join( @lockDir, LockfileFormat % id.to_s.gsub(/\W/, '_') ).untaint
  self.log.debug "Filename is: #@filename"
  @lockfile = nil
end

Instance Attribute Details

#lockDir ⇒ Object

The path to the directory where session lockfiles are kept.



89
90
91
 
# File 'lib/arrow/session/posixlock.rb', line 89

def lockDir
  @lockDir
end

Class Method Details

.clean(directory = DefaultLockDir, threshold = 3600) ⇒ Object

Clean the specified directory of lock files older than threshold seconds.



43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
 
# File 'lib/arrow/session/posixlock.rb', line 43

def self::clean( directory=DefaultLockDir, threshold=3600 )
  pat = File.join( directory, LockfileFormat.gsub(/%s/, '*') )
  threshold = Time.now - threshold
  Dir[ pat ].each do |file|
    if File.mtime( file ) < threshold
      Arrow::Logger[self].info \
      "Removing stale lockfile '%s'" % file
      begin
        fh = File.open( file, FileMode )
        fh.posixlock( File::LOCK_EX|File::LOCK_NB )
        File.delete( file )
        fh.posixlock( File::LOCK_UN )
        fh.close
      rescue => err
        Arrow::Logger[self].warning \
        "Could not clean up '%s': %s" %
          [ file, err.message ]
        next
      end
    end
  end
end

Instance Method Details

#finish ⇒ Object

Indicate to the lock that the caller will no longer be using it, and it may free any resources it had been using.



94
95
96
97
 
# File 'lib/arrow/session/posixlock.rb', line 94

def finish
  super
  self.close_lock_file
end