ACE/ace/MEM_SAP.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file    MEM_SAP.h
   6  *
   7  *  @author Nanbor Wang <nanbor@cs.wustl.edu>
   8  */
   9 //=============================================================================
  10
  11 #ifndef ACE_MEM_SAP_H
  12 #define ACE_MEM_SAP_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 // MEM_SAP requries position independent pointers to work
  23 #if (ACE_HAS_POSITION_INDEPENDENT_POINTERS == 1)
  24
  25 #include "ace/PI_Malloc.h"
  26 #include "ace/Malloc_T.h"
  27 #include "ace/MMAP_Memory_Pool.h"
  28 #include "ace/Process_Mutex.h"
  29
  30 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  31
  32 class ACE_MEM_SAP;
  33 class ACE_Reactive_MEM_IO;
  34 class ACE_MT_MEM_IO;
  35 class ACE_MEM_IO;
  36
  37 // Internal data structure
  38 // MEM_SAP uses to queue up
  39 // data.
  40 class ACE_MEM_SAP_Node
  41 {
  42 public:
  43   typedef ACE_Based_Pointer<ACE_MEM_SAP_Node> ACE_MEM_SAP_NODE_PTR;
  44
  45   /// Initialize the node with its capacity.
  46   ACE_MEM_SAP_Node (size_t cap);
  47
  48   /// Get the size of the data we hold.
  49   size_t size () const;
  50
  51   /// Get the capacity of this block of data.
  52   size_t capacity () const;
  53
  54   /// Get the pointer to the block of data we hold.
  55   void *data ();
  56
  57   /// The maximum size of this memory block.
  58   size_t capacity_;
  59
  60   /// The actualy size used.
  61   size_t size_;
  62
  63   ACE_MEM_SAP_NODE_PTR next_;
  64 };
  65
  66 /**
  67  * @class ACE_MEM_SAP
  68  *
  69  * @brief Defines the methods of shared memory management for
  70  * shared memory transport.
  71  */
  72 class ACE_Export ACE_MEM_SAP
  73 {
  74 public:
  75   typedef ACE_Malloc_T<ACE_MMAP_MEMORY_POOL, ACE_Process_Mutex, ACE_PI_Control_Block> MALLOC_TYPE;
  76   typedef ACE_MMAP_Memory_Pool_Options MALLOC_OPTIONS;
  77
  78   /// Destructor.
  79   virtual ~ACE_MEM_SAP ();
  80
  81   /**
  82    * Initialize the MEM_SAP object.
  83    */
  84   virtual int init (ACE_HANDLE handle,
  85                     const ACE_TCHAR *name,
  86                     MALLOC_OPTIONS *options) = 0;
  87
  88   /**
  89    * Finalizing the MEM_SAP object.  This method doesn't invoke
  90    * the <remove> method.
  91    */
  92   virtual int fini ();
  93
  94   /**
  95    * Fetch location of next available data into <recv_buffer_>.
  96    * As this operation read the address of the data off the socket
  97    * using ACE::recv, @a timeout only applies to ACE::recv.
  98    */
  99   virtual ssize_t recv_buf (ACE_MEM_SAP_Node *&buf,
 100                             int flags,
 101                             const ACE_Time_Value *timeout) = 0;
 102
 103   /**
 104    * Wait to to @a timeout amount of time to send @a buf.  If <send>
 105    * times out a -1 is returned with @c errno == ETIME.  If it succeeds
 106    * the number of bytes sent is returned.  */
 107   virtual ssize_t send_buf (ACE_MEM_SAP_Node *buf,
 108                             int flags,
 109                             const ACE_Time_Value *timeout) = 0;
 110
 111   /// request a buffer of size @a size.  Return 0 if the <shm_malloc_> is
 112   /// not initialized.
 113   ACE_MEM_SAP_Node *acquire_buffer (const ssize_t size);
 114
 115   /// release a buffer pointed by @a buf.  Return -1 if the <shm_malloc_>
 116   /// is not initialized.
 117   int release_buffer (ACE_MEM_SAP_Node *buf);
 118
 119   /// Dump the state of an object.
 120   void dump () const;
 121
 122   /// Declare the dynamic allocation hooks.
 123   ACE_ALLOC_HOOK_DECLARE;
 124
 125 protected:
 126   // = Class initializing methods to create/connect to a shared memory pool.
 127
 128   /**
 129    * Create a new shm_malloc object.  Return 0 if succeed and -1
 130    * otherwise.  This method should only be called from an acceptor
 131    * class that wants to create a new memory pool for inter process
 132    * communication.
 133    */
 134   int create_shm_malloc (const ACE_TCHAR *name,
 135                          MALLOC_OPTIONS *options);
 136
 137   /// Close down the share memory pool.  Clean up the
 138   /// mmap file if we are the last one using it.
 139   int close_shm_malloc ();
 140
 141   ACE_HANDLE handle_;
 142
 143   /// Data exchange channel.
 144   MALLOC_TYPE *shm_malloc_;
 145
 146   /// Constructor.  Prevent this class from being instantiated.
 147   ACE_MEM_SAP ();
 148 };
 149
 150 ACE_END_VERSIONED_NAMESPACE_DECL
 151
 152 #if defined (__ACE_INLINE__)
 153 #include "ace/MEM_SAP.inl"
 154 #endif /* __ACE_INLINE__ */
 155
 156 #endif /* ACE_HAS_POSITION_INDEPENDENT_POINTERS == 1 */
 157
 158 #include /**/ "ace/post.h"
 159
 160 #endif /* ACE_SOCK_IO_H */