boost/interprocess/sync/named_sharable_mutex.hpp

   1 //////////////////////////////////////////////////////////////////////////////
   2 //
   3 // (C) Copyright Ion Gaztanaga 2005-2012. Distributed under the Boost
   4 // Software License, Version 1.0. (See accompanying file
   5 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 //
   7 // See http://www.boost.org/libs/interprocess for documentation.
   8 //
   9 //////////////////////////////////////////////////////////////////////////////
  10
  11 #ifndef BOOST_INTERPROCESS_NAMED_SHARABLE_MUTEX_HPP
  12 #define BOOST_INTERPROCESS_NAMED_SHARABLE_MUTEX_HPP
  13
  14 #if defined(_MSC_VER)
  15 #  pragma once
  16 #endif
  17
  18 #include <boost/interprocess/detail/config_begin.hpp>
  19 #include <boost/interprocess/detail/workaround.hpp>
  20 #include <boost/interprocess/creation_tags.hpp>
  21 #include <boost/interprocess/exceptions.hpp>
  22 #include <boost/interprocess/shared_memory_object.hpp>
  23 #include <boost/interprocess/detail/managed_open_or_create_impl.hpp>
  24 #include <boost/interprocess/sync/interprocess_sharable_mutex.hpp>
  25 #include <boost/interprocess/detail/posix_time_types_wrk.hpp>
  26 #include <boost/interprocess/sync/shm/named_creation_functor.hpp>
  27 #include <boost/interprocess/permissions.hpp>
  28
  29 //!\file
  30 //!Describes a named sharable mutex class for inter-process synchronization
  31
  32 namespace boost {
  33 namespace interprocess {
  34
  35 #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
  36 namespace ipcdetail{ class interprocess_tester; }
  37 #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
  38
  39 class named_condition;
  40
  41 //!A sharable mutex with a global name, so it can be found from different
  42 //!processes. This mutex can't be placed in shared memory, and
  43 //!each process should have it's own named sharable mutex.
  44 class named_sharable_mutex
  45 {
  46    #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
  47    //Non-copyable
  48    named_sharable_mutex();
  49    named_sharable_mutex(const named_sharable_mutex &);
  50    named_sharable_mutex &operator=(const named_sharable_mutex &);
  51    #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
  52    public:
  53
  54    //!Creates a global sharable mutex with a name.
  55    //!If the sharable mutex can't be created throws interprocess_exception
  56    named_sharable_mutex(create_only_t create_only, const char *name, const permissions &perm = permissions());
  57
  58    //!Opens or creates a global sharable mutex with a name.
  59    //!If the sharable mutex is created, this call is equivalent to
  60    //!named_sharable_mutex(create_only_t, ...)
  61    //!If the sharable mutex is already created, this call is equivalent to
  62    //!named_sharable_mutex(open_only_t, ... ).
  63    named_sharable_mutex(open_or_create_t open_or_create, const char *name, const permissions &perm = permissions());
  64
  65    //!Opens a global sharable mutex with a name if that sharable mutex
  66    //!is previously.
  67    //!created. If it is not previously created this function throws
  68    //!interprocess_exception.
  69    named_sharable_mutex(open_only_t open_only, const char *name);
  70
  71    //!Destroys *this and indicates that the calling process is finished using
  72    //!the resource. The destructor function will deallocate
  73    //!any system resources allocated by the system for use by this process for
  74    //!this resource. The resource can still be opened again calling
  75    //!the open constructor overload. To erase the resource from the system
  76    //!use remove().
  77    ~named_sharable_mutex();
  78
  79    //Exclusive locking
  80
  81    //!Effects: The calling thread tries to obtain exclusive ownership of the mutex,
  82    //!   and if another thread has exclusive or sharable ownership of
  83    //!   the mutex, it waits until it can obtain the ownership.
  84    //!Throws: interprocess_exception on error.
  85    void lock();
  86
  87    //!Effects: The calling thread tries to acquire exclusive ownership of the mutex
  88    //!   without waiting. If no other thread has exclusive or sharable
  89    //!   ownership of the mutex this succeeds.
  90    //!Returns: If it can acquire exclusive ownership immediately returns true.
  91    //!   If it has to wait, returns false.
  92    //!Throws: interprocess_exception on error.
  93    bool try_lock();
  94
  95    //!Effects: The calling thread tries to acquire exclusive ownership of the mutex
  96    //!   waiting if necessary until no other thread has exclusive, or sharable
  97    //!   ownership of the mutex or abs_time is reached.
  98    //!Returns: If acquires exclusive ownership, returns true. Otherwise returns false.
  99    //!Throws: interprocess_exception on error.
 100    bool timed_lock(const boost::posix_time::ptime &abs_time);
 101
 102    //!Precondition: The thread must have exclusive ownership of the mutex.
 103    //!Effects: The calling thread releases the exclusive ownership of the mutex.
 104    //!Throws: An exception derived from interprocess_exception on error.
 105    void unlock();
 106
 107    //Sharable locking
 108
 109    //!Effects: The calling thread tries to obtain sharable ownership of the mutex,
 110    //!   and if another thread has exclusive ownership of the mutex,
 111    //!   waits until it can obtain the ownership.
 112    //!Throws: interprocess_exception on error.
 113    void lock_sharable();
 114
 115    //!Effects: The calling thread tries to acquire sharable ownership of the mutex
 116    //!   without waiting. If no other thread has exclusive ownership
 117    //!   of the mutex this succeeds.
 118    //!Returns: If it can acquire sharable ownership immediately returns true. If it
 119    //!   has to wait, returns false.
 120    //!Throws: interprocess_exception on error.
 121    bool try_lock_sharable();
 122
 123    //!Effects: The calling thread tries to acquire sharable ownership of the mutex
 124    //!   waiting if necessary until no other thread has exclusive
 125    //!   ownership of the mutex or abs_time is reached.
 126    //!Returns: If acquires sharable ownership, returns true. Otherwise returns false.
 127    //!Throws: interprocess_exception on error.
 128    bool timed_lock_sharable(const boost::posix_time::ptime &abs_time);
 129
 130    //!Precondition: The thread must have sharable ownership of the mutex.
 131    //!Effects: The calling thread releases the sharable ownership of the mutex.
 132    //!Throws: An exception derived from interprocess_exception on error.
 133    void unlock_sharable();
 134
 135    //!Erases a named sharable mutex from the system.
 136    //!Returns false on error. Never throws.
 137    static bool remove(const char *name);
 138
 139    #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
 140    private:
 141    friend class ipcdetail::interprocess_tester;
 142    void dont_close_on_destruction();
 143
 144    interprocess_sharable_mutex *mutex() const
 145    {  return static_cast<interprocess_sharable_mutex*>(m_shmem.get_user_address()); }
 146
 147    typedef ipcdetail::managed_open_or_create_impl<shared_memory_object, 0, true, false> open_create_impl_t;
 148    open_create_impl_t m_shmem;
 149    typedef ipcdetail::named_creation_functor<interprocess_sharable_mutex> construct_func_t;
 150    #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
 151 };
 152
 153 #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
 154
 155 inline named_sharable_mutex::~named_sharable_mutex()
 156 {}
 157
 158 inline named_sharable_mutex::named_sharable_mutex
 159    (create_only_t, const char *name, const permissions &perm)
 160    :  m_shmem  (create_only
 161                ,name
 162                ,sizeof(interprocess_sharable_mutex) +
 163                   open_create_impl_t::ManagedOpenOrCreateUserOffset
 164                ,read_write
 165                ,0
 166                ,construct_func_t(ipcdetail::DoCreate)
 167                ,perm)
 168 {}
 169
 170 inline named_sharable_mutex::named_sharable_mutex
 171    (open_or_create_t, const char *name, const permissions &perm)
 172    :  m_shmem  (open_or_create
 173                ,name
 174                ,sizeof(interprocess_sharable_mutex) +
 175                   open_create_impl_t::ManagedOpenOrCreateUserOffset
 176                ,read_write
 177                ,0
 178                ,construct_func_t(ipcdetail::DoOpenOrCreate)
 179                ,perm)
 180 {}
 181
 182 inline named_sharable_mutex::named_sharable_mutex
 183    (open_only_t, const char *name)
 184    :  m_shmem  (open_only
 185                ,name
 186                ,read_write
 187                ,0
 188                ,construct_func_t(ipcdetail::DoOpen))
 189 {}
 190
 191 inline void named_sharable_mutex::dont_close_on_destruction()
 192 {  ipcdetail::interprocess_tester::dont_close_on_destruction(m_shmem);  }
 193
 194 inline void named_sharable_mutex::lock()
 195 {  this->mutex()->lock();  }
 196
 197 inline void named_sharable_mutex::unlock()
 198 {  this->mutex()->unlock();  }
 199
 200 inline bool named_sharable_mutex::try_lock()
 201 {  return this->mutex()->try_lock();  }
 202
 203 inline bool named_sharable_mutex::timed_lock
 204    (const boost::posix_time::ptime &abs_time)
 205 {  return this->mutex()->timed_lock(abs_time);  }
 206
 207 inline void named_sharable_mutex::lock_sharable()
 208 {  this->mutex()->lock_sharable();  }
 209
 210 inline void named_sharable_mutex::unlock_sharable()
 211 {  this->mutex()->unlock_sharable();  }
 212
 213 inline bool named_sharable_mutex::try_lock_sharable()
 214 {  return this->mutex()->try_lock_sharable();  }
 215
 216 inline bool named_sharable_mutex::timed_lock_sharable
 217    (const boost::posix_time::ptime &abs_time)
 218 {  return this->mutex()->timed_lock_sharable(abs_time);  }
 219
 220 inline bool named_sharable_mutex::remove(const char *name)
 221 {  return shared_memory_object::remove(name); }
 222
 223 #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
 224
 225 }  //namespace interprocess {
 226 }  //namespace boost {
 227
 228 #include <boost/interprocess/detail/config_end.hpp>
 229
 230 #endif   //BOOST_INTERPROCESS_NAMED_SHARABLE_MUTEX_HPP