toolkit/profile/nsProfileLock.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef __nsProfileLock_h___
   7 #define __nsProfileLock_h___
   8
   9 #include "nsIFile.h"
  10
  11 class nsIProfileUnlocker;
  12
  13 #if defined(XP_WIN)
  14 #  include <windows.h>
  15 #endif
  16
  17 #if defined(XP_UNIX)
  18 #  include <signal.h>
  19 #  include "prclist.h"
  20 #endif
  21
  22 class nsProfileLock
  23 #if defined(XP_UNIX)
  24     : public PRCList
  25 #endif
  26 {
  27  public:
  28   nsProfileLock();
  29   nsProfileLock(nsProfileLock& src);
  30
  31   ~nsProfileLock();
  32
  33   nsProfileLock& operator=(nsProfileLock& rhs);
  34
  35   /**
  36    * Attempt to lock a profile directory.
  37    *
  38    * @param aProfileDir  [in] The profile directory to lock.
  39    * @param aUnlocker    [out] Optional. This is only returned when locking
  40    *                     fails with NS_ERROR_FILE_ACCESS_DENIED, and may not
  41    *                     be returned at all.
  42    * @throws NS_ERROR_FILE_ACCESS_DENIED if the profile is locked.
  43    */
  44   nsresult Lock(nsIFile* aProfileDir, nsIProfileUnlocker** aUnlocker);
  45
  46   /**
  47    * Unlock a profile directory.  If you're unlocking the directory because
  48    * the application is in the process of shutting down because of a fatal
  49    * signal, set aFatalSignal to true.
  50    */
  51   nsresult Unlock(bool aFatalSignal = false);
  52
  53   /**
  54    * Checks, if the given file has a name that matches potential lock file
  55    * names. It does not check, if it actually is the currently active lock.
  56    */
  57   static bool IsMaybeLockFile(nsIFile* aFile);
  58
  59   /**
  60    * Clean up any left over files in the directory.
  61    */
  62   nsresult Cleanup();
  63
  64   /**
  65    * Get the modification time of a replaced profile lock, otherwise 0.
  66    */
  67   nsresult GetReplacedLockTime(PRTime* aResult);
  68
  69  private:
  70   bool mHaveLock;
  71   PRTime mReplacedLockTime;
  72   nsCOMPtr<nsIFile> mLockFile;
  73
  74 #if defined(XP_WIN)
  75   HANDLE mLockFileHandle;
  76 #elif defined(XP_UNIX)
  77
  78   struct RemovePidLockFilesExiting {
  79     RemovePidLockFilesExiting() = default;
  80     ~RemovePidLockFilesExiting() { RemovePidLockFiles(false); }
  81   };
  82
  83   static void RemovePidLockFiles(bool aFatalSignal);
  84   static void FatalSignalHandler(int signo
  85 #  ifdef SA_SIGINFO
  86                                  ,
  87                                  siginfo_t* info, void* context
  88 #  endif
  89   );
  90   static PRCList mPidLockList;
  91
  92   nsresult LockWithFcntl(nsIFile* aLockFile,
  93                          nsIProfileUnlocker** aUnlocker = nullptr);
  94
  95   /**
  96    * @param aHaveFcntlLock if true, we've already acquired an fcntl lock so this
  97    * lock is merely an "obsolete" lock to keep out old Firefoxes
  98    */
  99   nsresult LockWithSymlink(nsIFile* aLockFile, bool aHaveFcntlLock);
 100
 101   char* mPidLockFileName;
 102   int mLockFileDesc;
 103 #endif
 104 };
 105
 106 #endif /* __nsProfileLock_h___ */