ceph/src/boost/libs/interprocess/include/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 #ifndef BOOST_CONFIG_HPP
  15 #  include <boost/config.hpp>
  16 #endif
  17 #
  18 #if defined(BOOST_HAS_PRAGMA_ONCE)
  19 #  pragma once
  20 #endif
  21
  22 #include <boost/interprocess/detail/config_begin.hpp>
  23 #include <boost/interprocess/detail/workaround.hpp>
  24 #include <boost/interprocess/creation_tags.hpp>
  25 #include <boost/interprocess/exceptions.hpp>
  26 #include <boost/interprocess/shared_memory_object.hpp>
  27 #include <boost/interprocess/detail/managed_open_or_create_impl.hpp>
  28 #include <boost/interprocess/sync/interprocess_sharable_mutex.hpp>
  29 #include <boost/interprocess/detail/posix_time_types_wrk.hpp>
  30 #include <boost/interprocess/sync/shm/named_creation_functor.hpp>
  31 #include <boost/interprocess/permissions.hpp>
  32
  33 //!\file
  34 //!Describes a named sharable mutex class for inter-process synchronization
  35
  36 namespace boost {
  37 namespace interprocess {
  38
  39 #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
  40 namespace ipcdetail{ class interprocess_tester; }
  41 #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
  42
  43 class named_condition;
  44
  45 //!A sharable mutex with a global name, so it can be found from different
  46 //!processes. This mutex can't be placed in shared memory, and
  47 //!each process should have it's own named sharable mutex.
  48 class named_sharable_mutex
  49 {
  50    #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
  51    //Non-copyable
  52    named_sharable_mutex();
  53    named_sharable_mutex(const named_sharable_mutex &);
  54    named_sharable_mutex &operator=(const named_sharable_mutex &);
  55    #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
  56    public:
  57
  58    //!Creates a global sharable mutex with a name.
  59    //!If the sharable mutex can't be created throws interprocess_exception
  60    named_sharable_mutex(create_only_t create_only, const char *name, const permissions &perm = permissions());
  61
  62    //!Opens or creates a global sharable mutex with a name.
  63    //!If the sharable mutex is created, this call is equivalent to
  64    //!named_sharable_mutex(create_only_t, ...)
  65    //!If the sharable mutex is already created, this call is equivalent to
  66    //!named_sharable_mutex(open_only_t, ... ).
  67    named_sharable_mutex(open_or_create_t open_or_create, const char *name, const permissions &perm = permissions());
  68
  69    //!Opens a global sharable mutex with a name if that sharable mutex
  70    //!is previously.
  71    //!created. If it is not previously created this function throws
  72    //!interprocess_exception.
  73    named_sharable_mutex(open_only_t open_only, const char *name);
  74
  75    //!Destroys *this and indicates that the calling process is finished using
  76    //!the resource. The destructor function will deallocate
  77    //!any system resources allocated by the system for use by this process for
  78    //!this resource. The resource can still be opened again calling
  79    //!the open constructor overload. To erase the resource from the system
  80    //!use remove().
  81    ~named_sharable_mutex();
  82
  83    //Exclusive locking
  84
  85    //!Effects: The calling thread tries to obtain exclusive ownership of the mutex,
  86    //!   and if another thread has exclusive or sharable ownership of
  87    //!   the mutex, it waits until it can obtain the ownership.
  88    //!Throws: interprocess_exception on error.
  89    void lock();
  90
  91    //!Effects: The calling thread tries to acquire exclusive ownership of the mutex
  92    //!   without waiting. If no other thread has exclusive or sharable
  93    //!   ownership of the mutex this succeeds.
  94    //!Returns: If it can acquire exclusive ownership immediately returns true.
  95    //!   If it has to wait, returns false.
  96    //!Throws: interprocess_exception on error.
  97    bool try_lock();
  98
  99    //!Effects: The calling thread tries to acquire exclusive ownership of the mutex
 100    //!   waiting if necessary until no other thread has exclusive, or sharable
 101    //!   ownership of the mutex or abs_time is reached.
 102    //!Returns: If acquires exclusive ownership, returns true. Otherwise returns false.
 103    //!Throws: interprocess_exception on error.
 104    bool timed_lock(const boost::posix_time::ptime &abs_time);
 105
 106    //!Precondition: The thread must have exclusive ownership of the mutex.
 107    //!Effects: The calling thread releases the exclusive ownership of the mutex.
 108    //!Throws: An exception derived from interprocess_exception on error.
 109    void unlock();
 110
 111    //Sharable locking
 112
 113    //!Effects: The calling thread tries to obtain sharable ownership of the mutex,
 114    //!   and if another thread has exclusive ownership of the mutex,
 115    //!   waits until it can obtain the ownership.
 116    //!Throws: interprocess_exception on error.
 117    void lock_sharable();
 118
 119    //!Effects: The calling thread tries to acquire sharable ownership of the mutex
 120    //!   without waiting. If no other thread has exclusive ownership
 121    //!   of the mutex this succeeds.
 122    //!Returns: If it can acquire sharable ownership immediately returns true. If it
 123    //!   has to wait, returns false.
 124    //!Throws: interprocess_exception on error.
 125    bool try_lock_sharable();
 126
 127    //!Effects: The calling thread tries to acquire sharable ownership of the mutex
 128    //!   waiting if necessary until no other thread has exclusive
 129    //!   ownership of the mutex or abs_time is reached.
 130    //!Returns: If acquires sharable ownership, returns true. Otherwise returns false.
 131    //!Throws: interprocess_exception on error.
 132    bool timed_lock_sharable(const boost::posix_time::ptime &abs_time);
 133
 134    //!Precondition: The thread must have sharable ownership of the mutex.
 135    //!Effects: The calling thread releases the sharable ownership of the mutex.
 136    //!Throws: An exception derived from interprocess_exception on error.
 137    void unlock_sharable();
 138
 139    //!Erases a named sharable mutex from the system.
 140    //!Returns false on error. Never throws.
 141    static bool remove(const char *name);
 142
 143    #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
 144    private:
 145    friend class ipcdetail::interprocess_tester;
 146    void dont_close_on_destruction();
 147
 148    interprocess_sharable_mutex *mutex() const
 149    {  return static_cast<interprocess_sharable_mutex*>(m_shmem.get_user_address()); }
 150
 151    typedef ipcdetail::managed_open_or_create_impl<shared_memory_object, 0, true, false> open_create_impl_t;
 152    open_create_impl_t m_shmem;
 153    typedef ipcdetail::named_creation_functor<interprocess_sharable_mutex> construct_func_t;
 154    #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
 155 };
 156
 157 #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
 158
 159 inline named_sharable_mutex::~named_sharable_mutex()
 160 {}
 161
 162 inline named_sharable_mutex::named_sharable_mutex
 163    (create_only_t, const char *name, const permissions &perm)
 164    :  m_shmem  (create_only
 165                ,name
 166                ,sizeof(interprocess_sharable_mutex) +
 167                   open_create_impl_t::ManagedOpenOrCreateUserOffset
 168                ,read_write
 169                ,0
 170                ,construct_func_t(ipcdetail::DoCreate)
 171                ,perm)
 172 {}
 173
 174 inline named_sharable_mutex::named_sharable_mutex
 175    (open_or_create_t, const char *name, const permissions &perm)
 176    :  m_shmem  (open_or_create
 177                ,name
 178                ,sizeof(interprocess_sharable_mutex) +
 179                   open_create_impl_t::ManagedOpenOrCreateUserOffset
 180                ,read_write
 181                ,0
 182                ,construct_func_t(ipcdetail::DoOpenOrCreate)
 183                ,perm)
 184 {}
 185
 186 inline named_sharable_mutex::named_sharable_mutex
 187    (open_only_t, const char *name)
 188    :  m_shmem  (open_only
 189                ,name
 190                ,read_write
 191                ,0
 192                ,construct_func_t(ipcdetail::DoOpen))
 193 {}
 194
 195 inline void named_sharable_mutex::dont_close_on_destruction()
 196 {  ipcdetail::interprocess_tester::dont_close_on_destruction(m_shmem);  }
 197
 198 inline void named_sharable_mutex::lock()
 199 {  this->mutex()->lock();  }
 200
 201 inline void named_sharable_mutex::unlock()
 202 {  this->mutex()->unlock();  }
 203
 204 inline bool named_sharable_mutex::try_lock()
 205 {  return this->mutex()->try_lock();  }
 206
 207 inline bool named_sharable_mutex::timed_lock
 208    (const boost::posix_time::ptime &abs_time)
 209 {  return this->mutex()->timed_lock(abs_time);  }
 210
 211 inline void named_sharable_mutex::lock_sharable()
 212 {  this->mutex()->lock_sharable();  }
 213
 214 inline void named_sharable_mutex::unlock_sharable()
 215 {  this->mutex()->unlock_sharable();  }
 216
 217 inline bool named_sharable_mutex::try_lock_sharable()
 218 {  return this->mutex()->try_lock_sharable();  }
 219
 220 inline bool named_sharable_mutex::timed_lock_sharable
 221    (const boost::posix_time::ptime &abs_time)
 222 {  return this->mutex()->timed_lock_sharable(abs_time);  }
 223
 224 inline bool named_sharable_mutex::remove(const char *name)
 225 {  return shared_memory_object::remove(name); }
 226
 227 #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
 228
 229 }  //namespace interprocess {
 230 }  //namespace boost {
 231
 232 #include <boost/interprocess/detail/config_end.hpp>
 233
 234 #endif   //BOOST_INTERPROCESS_NAMED_SHARABLE_MUTEX_HPP