/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 2002
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Conrad Carlen <ccarlen@netscape.com>
 *   Brendan Eich <brendan@mozilla.org>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
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 * decision by deleting the provisions above and replace them with the notice
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 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#ifndef __nsProfileLock_h___
#define __nsProfileLock_h___

#include "nsILocalFile.h"

class nsIProfileUnlocker;

#if defined (XP_WIN)
#include <windows.h>
#endif

#if defined (XP_OS2)
#define INCL_DOSERRORS
#define INCL_DOSFILEMGR
#include <os2.h>
#endif

#if defined (XP_UNIX)
#include <signal.h>
#include "prclist.h"
#endif

class nsProfileLock
#if defined (XP_UNIX)
  : public PRCList
#endif
{
public:
                            nsProfileLock();
                            nsProfileLock(nsProfileLock& src);

                            ~nsProfileLock();
 
    nsProfileLock&          operator=(nsProfileLock& rhs);
                       
    /**
     * Attempt to lock a profile directory.
     *
     * @param aProfileDir  [in] The profile directory to lock.
     * @param aUnlocker    [out] Optional. This is only returned when locking
     *                     fails with NS_ERROR_FILE_ACCESS_DENIED, and may not
     *                     be returned at all.
     * @throws NS_ERROR_FILE_ACCESS_DENIED if the profile is locked.
     */
    nsresult                Lock(nsILocalFile* aProfileDir, nsIProfileUnlocker* *aUnlocker);

    /**
     * Unlock a profile directory.  If you're unlocking the directory because
     * the application is in the process of shutting down because of a fatal
     * signal, set aFatalSignal to true.
     */
    nsresult                Unlock(bool aFatalSignal = false);
        
private:
    bool                    mHaveLock;

#if defined (XP_WIN)
    HANDLE                  mLockFileHandle;
#elif defined (XP_OS2)
    LHANDLE                 mLockFileHandle;
#elif defined (XP_UNIX)

    struct RemovePidLockFilesExiting {
        RemovePidLockFilesExiting() {}
        ~RemovePidLockFilesExiting() {
            RemovePidLockFiles(false);
        }
    };

    static void             RemovePidLockFiles(bool aFatalSignal);
    static void             FatalSignalHandler(int signo
#ifdef SA_SIGINFO
                                               , siginfo_t *info, void *context
#endif
                                               );
    static PRCList          mPidLockList;

    nsresult                LockWithFcntl(const nsACString& lockFilePath);

    /**
     * @param aHaveFcntlLock if true, we've already acquired an fcntl lock so this
     * lock is merely an "obsolete" lock to keep out old Firefoxes
     */
    nsresult                LockWithSymlink(const nsACString& lockFilePath, bool aHaveFcntlLock);

    char*                   mPidLockFileName;
    int                     mLockFileDesc;
#endif

};

#endif /* __nsProfileLock_h___ */
