dep/ACE_wrappers/ace/SUN_Proactor.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file    SUN_Proactor.h
   6  *
   7  *  $Id: SUN_Proactor.h 80826 2008-03-04 14:51:23Z wotte $
   8  *
   9  *  @author Alexander Libman <alibman@baltimore.com>
  10  */
  11 //=============================================================================
  12
  13 #ifndef ACE_SUN_PROACTOR_H
  14 #define ACE_SUN_PROACTOR_H
  15
  16 #include /**/ "ace/config-all.h"
  17
  18 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  19 # pragma once
  20 #endif /* ACE_LACKS_PRAGMA_ONCE */
  21
  22 #if defined (ACE_HAS_AIO_CALLS) && defined (sun)
  23
  24 #include "ace/POSIX_Proactor.h"
  25 #include /**/ <sys/asynch.h>    // Sun native aio calls
  26
  27 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  28
  29 /**
  30  * @class ACE_SUN_Proactor
  31  *
  32  * @brief Implementation of the fast and reliable Proactor
  33  * for SunOS 5.6, 5.7, etc.
  34  *
  35  * This proactor, based on ACE_POSIX_AIOCB_Proactor,
  36  * works with Sun native interface for aio calls.
  37  * POSIX_API          Native SUN_API
  38  * aio_read           aioread
  39  * aio_write          aiowrite
  40  * aio_suspend        aiowait
  41  * aio_error          aio_result_t.errno
  42  * aio_return         aio_result_t.return
  43  * On Solaris, the Sun <aio*()> native implementation is more
  44  * reliable and efficient than POSIX <aio_*()> implementation.
  45  * There is a problem of lost RT signals with POSIX, if we start
  46  * more than SIGQUEUEMAX asynchronous operations at the same
  47  * time.
  48  * The Sun <aiocb> it is not the standard POSX <aiocb>, instead,
  49  * it has the following structure:
  50  * typedef struct aiocb
  51  * {
  52  * int          aio_fildes;     File descriptor
  53  * void         *aio_buf;       buffer location
  54  * size_t       aio_nbytes;     length of transfer
  55  * off_t        aio_offset;     file offset
  56  * int          aio_reqprio;    request priority offset
  57  * sigevent     aio_sigevent;   signal number and offset
  58  * int          aio_lio_opcode; listio operation
  59  * aio_result_t aio_resultp;    results
  60  * int          aio_state;      state flag for List I/O
  61  * int          aio__pad[1];    extension padding
  62  * };
  63  */
  64 class ACE_Export ACE_SUN_Proactor : public ACE_POSIX_AIOCB_Proactor
  65 {
  66
  67 public:
  68   virtual Proactor_Type get_impl_type (void);
  69
  70   /// Destructor.
  71   virtual ~ACE_SUN_Proactor (void);
  72
  73   /// Constructor defines max number asynchronous operations that can
  74   /// be started at the same time.
  75   ACE_SUN_Proactor (size_t max_aio_operations = ACE_AIO_DEFAULT_SIZE);
  76
  77 protected:
  78   /**
  79    * Dispatch a single set of events.  If @a wait_time elapses before
  80    * any events occur, return 0.  Return 1 on success i.e., when a
  81    * completion is dispatched, non-zero (-1) on errors and errno is
  82    * set accordingly.
  83    */
  84   virtual int handle_events (ACE_Time_Value &wait_time);
  85
  86   /**
  87    * Block indefinitely until at least one event is dispatched.
  88    * Dispatch a single set of events. Return 1 on success i.e., when a
  89    * completion is dispatched, non-zero (-1) on errors and errno is
  90    * set accordingly.
  91    */
  92   virtual int handle_events (void);
  93
  94   /// Internal completion detection and dispatching.
  95   int handle_events_i (ACE_Time_Value *delta);
  96
  97   /// Initiate an aio operation.
  98   virtual int start_aio_i (ACE_POSIX_Asynch_Result *result);
  99
 100   /// Check AIO for completion, error and result status
 101   /// Return: 1 - AIO completed , 0 - not completed yet
 102   virtual int get_result_status (ACE_POSIX_Asynch_Result* asynch_result,
 103                                  int &error_status,
 104                                  size_t &transfer_count);
 105
 106   /// Extract the results of aio.
 107   ACE_POSIX_Asynch_Result *find_completed_aio (aio_result_t *result,
 108                                                int &error_status,
 109                                                size_t &transfer_count);
 110
 111   /// From ACE_POSIX_AIOCB_Proactor.
 112   /// Attempt to cancel running request
 113   virtual int cancel_aiocb (ACE_POSIX_Asynch_Result *result);
 114
 115   /// Specific Sun aiowait
 116   int wait_for_start (ACE_Time_Value * abstime);
 117
 118   /// Condition variable .
 119   /// used to wait the first AIO start
 120   ACE_SYNCH_CONDITION condition_;
 121 };
 122
 123 ACE_END_VERSIONED_NAMESPACE_DECL
 124
 125 #endif /* ACE_HAS_AIO_CALLS && sun */
 126 #endif /* ACE_SUN_PROACTOR_H*/