cb.h

基于EthernetIP协议的应用程序,可以读取AB公司Controllogix系列Ethernetip协议PLC数据. 此软件代码可用于工业控制.

/****************************************************************************
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**
** File Name
** ---------
**
** CB.H
**
*****************************************************************************
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**
** Description
** -----------
**
** Communication buffer services definitions.
**
** Communications buffers (ComBufs) are a structure with an attached buffer
** that provides a way for headers to be prepended and stripped from a packet
** as it passes through the communications stack without data copies or
** moves.
**
*****************************************************************************
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**
** Source Change Indices
** ---------------------
**
** Porting: <none>0----<major>         Customization: <none>0----<major>
**
*****************************************************************************
*****************************************************************************
**
** Services List
** -------------
**
**    CB_AttachComBuf()          - Increment ComBuf UseCount to "attach" user
**    CB_ClearComBuf()           - Clear out the contents of a ComBuf
**    CB_ClearAndExpandComBuf()  - Forcibly set the data size of a ComBuf
**    CB_DeleteComBuf()          - Delete a ComBuf
**    CB_ExpandComBuf()          - Expand the data size of a ComBuf
**    CB_GetDataPtrComBuf()      - Return the data pointer of the ComBuf
**    CB_GetDataSizeComBuf()     - Return the current data size of a ComBuf
**    CB_NewComBuf()             - Create a new ComBuf
**    CB_PrependComBuf()         - Expand and put new data into a ComBuf
**    CB_ShrinkComBuf()          - Reduce the data size of a ComBuf
**    CB_ShrinkOffsetComBuf()    - Remove the middle portion of a ComBuf
**    CB_StripComBuf()           - Take data from a combuf and shrink it
**    CB_TradeForBigger()        - Trade ComBuf (if needed) to ensure space
**    CB_TradeForBiggerClear()   - Trade ComBuf (if needed) to ensure space
**    CB_WordAlignComBuf()       - Ensure first data byte is word aligned
**
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**                                                                         **
** ETHERNET/IP EXAMPLE CODE                                                **
** COPYRIGHT (c) 2000-2005 ODVA (Open DeviceNet Vendor Association)		   **
**						   & ControlNet International Ltd.                 **
**                                                                         **
** All rights reserved, except as specifically licensed in writing.        **
** Use of the Ethernet/IP Example Protocol Software is subject to          **
** ODVA's and ControlNet International's Terms of Use Agreement.           **
** The following work constitutes example program code and is intended     **
** merely to illustrate useful programming techniques.  The user is        **
** responsible for applying the code correctly.  The code is provided      **
** AS IS without warranty and is in no way guaranteed to be error-free.    **
**                                                                         **
*****************************************************************************
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*/

/****************************************************************************
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**
** Change Log
** ----------
**
**
*****************************************************************************
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*/

#ifndef CB_H
#define CB_H



/****************************************************************************
**
** Typedefs
**
*****************************************************************************
*/

/*---------------------------------------------------------------------------
**
** CB_ComBufType
**
** Combuf control structure definition. It is assumed that the data buffer
** immediately follows this structure.
**
**---------------------------------------------------------------------------
*/

typedef struct CB_ComBufType
{
   UINT8  *pData;          /* pointer to start of active buffer data    */
   UINT16  iReqSize;       /* requested allocation size                 */
   UINT16  iBufSize;       /* max size of the buffer (heap block size)  */
   UINT16  iDataSize;      /* size of active data in buffer             */
   UINT8   bUseCount;      /* use count for shared ComBufs              */
   UINT8   bPad;           /* make sure things stay word aligned        */
}
CB_ComBufType;



/****************************************************************************
**
** Public Services
**
*****************************************************************************
*/

/*---------------------------------------------------------------------------
**
** CB_AttachComBuf()
**
** Increment UseCount of ComBuf to indicate another user is "attached"
** and actively using the combuf. Call CB_DeleteComBuf to "detach" a user
** from a combuf. The last user to "detach" from the combuf causes the
** combuf to be freed back to the heap.
**
**---------------------------------------------------------------------------
**
** Inputs:
**    pC                   - Pointer to Combuf
**
** Outputs:
**    None
**
** Usage:
**    CB_AttachComBuf( pComBuf );
**
**---------------------------------------------------------------------------
*/

#define CB_AttachComBuf( pComBuf ) \
   {                               \
      (pComBuf)->bUseCount++;      \
   }



/*---------------------------------------------------------------------------
**
** CB_ClearComBuf()
**
** Reset a ComBuf to its initial empty state.
**
**---------------------------------------------------------------------------
**
** Inputs:
**    pComBuf              - Pointer to Combuf
**
** Outputs:
**    None
**
** Usage:
**    CB_ClearComBuf( pComBuf );
**
**---------------------------------------------------------------------------
*/

#define CB_ClearComBuf( pComBuf )                                                   \
   {                                               \
      (pComBuf)->iDataSize = 0;                    \
      (pComBuf)->pData = (UINT8*)(pComBuf) +       \
                         sizeof( CB_ComBufType ) + \
                         (pComBuf)->iBufSize;      \
   }



/*---------------------------------------------------------------------------
**
** CB_ClearAndExpandComBuf()
**
** Set ComBuf data size to the specified value and adjust the ComBuf data
** pointer to correspond.
**
**---------------------------------------------------------------------------
**
** Inputs:
**    pComBuf                 - Pointer to ComBuf
**    iSize                   - New data size
**
** Outputs:
**    None
**
** Usage:
**    CB_ClearAndExpandComBuf( pComBuf, iSize );
**
**---------------------------------------------------------------------------
*/

#define CB_ClearAndExpandComBuf( pComBuf, iSize )       \
   {                                                    \
      (pComBuf)->iDataSize = (iSize);                   \
      (pComBuf)->pData = (UINT8*)(pComBuf) +            \
                              sizeof( CB_ComBufType ) + \
                              (pComBuf)->iBufSize -     \
                              (iSize);                  \
   }



/*---------------------------------------------------------------------------
**
** CB_DeleteComBuf()
**
** Detach one user from a ComBuf.
** Delete and free its heap memory if this was the last user.
**
**---------------------------------------------------------------------------
**
** Inputs:
**    pComBuf                 - Pointer to Combuf
**
** Outputs:
**    Return                  - TRUE if combuf deleted
**                              FALSE if not deleted
**
** Usage:
**    if( CB_DeleteCombuf( pComBuf ) )...
**
**---------------------------------------------------------------------------
*/

EXTFUNC BOOL CB_DeleteComBuf( CB_ComBufType *pComBuf );


/*---------------------------------------------------------------------------
**
** CB_ExpandComBuf()
**
** Make room in front of a packet in a ComBuf.
**
**---------------------------------------------------------------------------
**
** Inputs:
**    pComBuf                 - Pointer to ComBuf
**    iSize                   - Size of expansion area
**
** Outputs:
**    None
**
** Usage:
**    CB_ExpandComBuf( pComBuf, iSize );
**
**---------------------------------------------------------------------------
*/

#define CB_ExpandComBuf( pComBuf, iSize ) \
   {                                      \
      GS_LogEventIf( (pComBuf)->iDataSize + (iSize) > (pComBuf)->iBufSize, \
                     CB_OVERFLOW,         \
                     ((pComBuf)->iDataSize + (iSize) - (pComBuf)->iBufSize) /* jjw 9/26/99 added parenth for typedef on msvc */, \
                     (void*)(pComBuf),    \
                     FATAL );             \
      (pComBuf)->pData     -= (iSize);    \
      (pComBuf)->iDataSize += (iSize);    \
   }



/*---------------------------------------------------------------------------
**
** CB_GetDataPtrComBuf()
**
** Reference the data ptr (to the packet currently resident) in the ComBuf.
**
**---------------------------------------------------------------------------
**
** Inputs:
**    pComBuf                 - Pointer to ComBuf
**
** Outputs:
**    Return                  - Pointer to the start of the data in ComBuf
**
** Usage:
**    pData = CB_GetDataPtrComBuf( pComBuf );
**
**---------------------------------------------------------------------------
*/

#define CB_GetDataPtrComBuf( pComBuf )  ( (void*)(pComBuf)->pData )



/*---------------------------------------------------------------------------
**
** CB_GetDataSizeComBuf()
**