DirectoryLock.h

//-*-C++-*-
/***************************************************************************
 *
 *   Copyright (C) 2012 by Willem van Straten
 *   Licensed under the Academic Free License version 2.1
 *
 ***************************************************************************/
 
/* Util/genutil/DirectoryLock.h */
 
#ifndef __DirectoryLock_h
#define __DirectoryLock_h
 
#include "ThreadContext.h"
#include <string>
 
class DirectoryLock
{
 
 public:
 
  DirectoryLock (const char* path = 0);
 
  // set the directory in which system calls will be made
  void set_directory (const std::string&);
  // get the directory in which system calls will be made
  std::string get_directory () const;
 
  // get the name of the file used to lock the directory
  std::string get_lockfile () const;
 
  // lock the working directory
  void lock ();
  // unlock the working directory
  void unlock ();
  // clean the working directory
  void clean ();
 
  class Push;
 
protected:
 
  std::string path;
  std::string lockfile;
 
private:
 
  int lock_fd;
  bool have_lock;
  ThreadContext* context;
 
  void open_lockfile ();
 
};
 
class DirectoryLock::Push
{
  std::string current;
  DirectoryLock& lock;
 
  // disable copy constructor and assignment operator
  Push (const Push&);
  const Push& operator= (const Push&);
 
public:
 
  Push (DirectoryLock& lock);
 
  ~Push ();
  
};
 
#endif