ACE/ace/SV_Shared_Memory.h

   1 // -*- C++ -*-
   2
   3 //==========================================================================
   4 /**
   5  *  @file    SV_Shared_Memory.h
   6  *
   7  *  @author Douglas C. Schmidt <d.schmidt@vanderbilt.edu>
   8  */
   9 //==========================================================================
  10
  11 #ifndef ACE_SV_SHARED_MEMORY_H
  12 #define ACE_SV_SHARED_MEMORY_H
  13
  14 #include /**/ "ace/pre.h"
  15
  16 #include /**/ "ace/ACE_export.h"
  17
  18 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  19 # pragma once
  20 #endif /* ACE_LACKS_PRAGMA_ONCE */
  21
  22 #include "ace/os_include/sys/os_stat.h"
  23 #include "ace/os_include/sys/os_ipc.h"
  24 #include "ace/Default_Constants.h"
  25
  26 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  27
  28 /**
  29  * @class ACE_SV_Shared_Memory
  30  *
  31  * @brief This is a wrapper for System V shared memory.
  32  */
  33 class ACE_Export ACE_SV_Shared_Memory
  34 {
  35 public:
  36   enum
  37   {
  38     ACE_CREATE = IPC_CREAT,
  39     ACE_OPEN   = 0
  40   };
  41
  42   ACE_SV_Shared_Memory ();
  43   ACE_SV_Shared_Memory (key_t external_id,
  44                         size_t size,
  45                         int create,
  46                         int perms = ACE_DEFAULT_FILE_PERMS,
  47                         void *virtual_addr = 0,
  48                         int flags = 0);
  49
  50   ACE_SV_Shared_Memory (ACE_HANDLE internal_id,
  51                         int flags = 0);
  52
  53   int  open (key_t external_id,
  54              size_t size,
  55              int create = ACE_SV_Shared_Memory::ACE_OPEN,
  56              int perms = ACE_DEFAULT_FILE_PERMS);
  57
  58   int  open_and_attach (key_t external_id,
  59                         size_t size,
  60                         int create = ACE_SV_Shared_Memory::ACE_OPEN,
  61                         int perms = ACE_DEFAULT_FILE_PERMS,
  62                         void *virtual_addr = 0,
  63                         int flags = 0);
  64
  65   /// Attach this shared memory segment.
  66   int  attach (void *virtual_addr = 0, int flags = 0);
  67
  68   /// Detach this shared memory segment.
  69   int  detach ();
  70
  71   /// Remove this shared memory segment.
  72   int  remove ();
  73
  74   /// Forward to underlying System V <shmctl>.
  75   int  control (int cmd, void *buf);
  76
  77   // = Segment-related info.
  78   void *get_segment_ptr () const;
  79   size_t get_segment_size () const;
  80
  81   /// Return the ID of the shared memory segment (i.e., an ACE_HANDLE).
  82   ACE_HANDLE get_id () const;
  83
  84   /// Dump the state of an object.
  85   void dump () const;
  86
  87   /// Declare the dynamic allocation hooks.
  88   ACE_ALLOC_HOOK_DECLARE;
  89
  90 protected:
  91   enum
  92   {
  93     /// Most restrictive alignment.
  94     ALIGN_WORDB = 8
  95   };
  96
  97   /// Internal identifier.
  98   ACE_HANDLE internal_id_;
  99
 100   /// Size of the mapped segment.
 101   size_t size_;
 102
 103   /// Pointer to the beginning of the segment.
 104   void *segment_ptr_;
 105
 106   /// Round up to an appropriate page size.
 107   size_t round_up (size_t len);
 108 };
 109
 110 ACE_END_VERSIONED_NAMESPACE_DECL
 111
 112 #if defined (__ACE_INLINE__)
 113 #include "ace/SV_Shared_Memory.inl"
 114 #endif /* __ACE_INLINE__ */
 115
 116 #include /**/ "ace/post.h"
 117
 118 #endif /* ACE_SV_SHARED_MEMORY_H */