C DLL mit Delphi verwenden

[Beowulf01]

C Beispiel:

Header-File

Code:

#undef ATTR_PACKED
#if defined(_MSC_VER)
 #pragma pack( push, safe_old_packing, 4 )
 #define ATTR_PACKED
...
#endif

#ifdef PASCAL
    #define CODE_ATTR __stdcall
#else
    #define CODE_ATTR
#endif

typedef IOXS    (*CBF_DATA_WRITE) /* write data to IO stack (local ==> remote) */
       (UINT32          DevHndl,       /* Handle for device */
        DEV_ADDR      * pAddr,         /* address */
        UINT32          BufLen,        /* length of input data */
        UINT8         * pBuffer,       /* Ptr to data buffer to write to */
        IOXS            Iocs);         /* remote status */

typedef IOXS    (*CBF_DATA_READ)  /* read data from IO stack (remote ==> local) */
       (UINT32          DevHndl,       /* Handle for device */
        DEV_ADDR      * pAddr,         /* address */
        UINT32          BufLen,        /* length of input data */
        UINT8         * pBuffer,       /* Ptr to data buffer to read from */
        IOXS            Iops);         /* provider status */

/* structure for callback function block */
typedef struct {
    UINT32               size;          // size of struct = sizeof(CBF_FUNCTIONS)
    CBF_DATA_WRITE       cbf_data_write;
    CBF_DATA_READ        cbf_data_read;
} ATTR_PACKED CBF_FUNCTIONS;

UINT32 CODE_ATTR device_open (
        UINT16          DeviceId,       /* [in]  device id */
        CBF_FUNCTIONS * pCbf,           /* [in]  cbf */
        UINT32        * pDevHndl);      /* [out] device handle */

Hätte ich vorher schon genauer hingeschaut, hätte ich gesehen, dass es stdcall ist...(s.o.)

Und hier meine Umsetzung in Delphi:

Code:

{$Z4}

TCbfDataRWProc  =
  procedure(
    DevHndl     : UINT32;
    pAddr       : PTDevAddr;
    BufLen      : UINT32;
    pBuffer     : PTUINT8;
    Ioxs        : EIoXS
  ); EIoXS; stdcall;

TCbfFunctions =
  packed record
    size                : UINT32;
    cbf_data_write      : TCbfDataRWProc;
    cbf_data_read       : TCbfDataRWProc;
  end;

PTCbfFunctions = ^TCbfFunctions;

function device_open(
  DeviceId        : UINT16;
  pCbf            : PTCbfFunctions;
  pDevHndl        : PTUINT32
  ): UINT32; stdcall;