ioc.c

nuclues plus 源代码程序

/*************************************************************************/
/*                                                                       */
/*        Copyright (c) 1993-1996 Accelerated Technology, Inc.           */
/*                                                                       */
/* PROPRIETARY RIGHTS of Accelerated Technology are involved in the      */
/* subject matter of this material.  All manufacturing, reproduction,    */
/* use, and sales rights pertaining to this subject matter are governed  */
/* by the license agreement.  The recipient of this software implicitly  */
/* accepts the terms of the license.                                     */
/*                                                                       */
/*************************************************************************/

/*************************************************************************/
/*                                                                       */
/* FILE NAME                                            VERSION          */
/*                                                                       */
/*      ioc.c                                           PLUS  1.2        */
/*                                                                       */
/* COMPONENT                                                             */
/*                                                                       */
/*      IO - Input/Output Driver Management                              */
/*                                                                       */
/* DESCRIPTION                                                           */
/*                                                                       */
/*      This file contains the core routines for the I/O Driver          */
/*      Management component.                                            */
/*                                                                       */
/* AUTHOR                                                                */
/*                                                                       */
/*      William E. Lamie, Accelerated Technology, Inc.                   */
/*                                                                       */
/* DATA STRUCTURES                                                       */
/*                                                                       */
/*      None                                                             */
/*                                                                       */
/* FUNCTIONS                                                             */
/*                                                                       */
/*      IOC_Create_Driver                   Create an I/O driver         */
/*      IOC_Delete_Driver                   Delete an I/O driver         */
/*      IOC_Request_Driver                  Make an I/O driver request   */
/*      IOC_Resume_Driver                   Resume a task suspended in   */
/*                                            an I/O driver              */
/*      IOC_Suspend_Driver                  Suspend a task inside an I/O */
/*                                            driver                     */
/*                                                                       */
/* DEPENDENCIES                                                          */
/*                                                                       */
/*      cs_extr.h                           Common Service functions     */
/*      tc_extr.h                           Thread Control functions     */
/*      io_extr.h                           I/O driver functions         */
/*      hi_extr.h                           History functions            */
/*                                                                       */
/* HISTORY                                                               */
/*                                                                       */
/*         NAME            DATE                    REMARKS               */
/*                                                                       */
/*      W. Lamie        03-01-1993      Created initial version 1.0      */
/*      D. Lamie        04-19-1993      Verified version 1.0             */
/*      W. Lamie        08-09-1993      Corrected pointer retrieval      */
/*                                       loop, resulting in version 1.0a */
/*      D. Lamie        08-09-1993      Verified version 1.0a            */
/*      W. Lamie        03-01-1994      Moved non-core functions into    */
/*                                        supplemental files, changed    */
/*                                        function interfaces to match   */
/*                                        those in prototype, changed    */
/*                                        protection logic to reduce     */
/*                                        overhead, resulting in         */
/*                                        version 1.1                    */
/*      R. Pfaff -                                                       */
/*      D. Lamie        03-15-1994      Verified version 1.1             */
/*      M.Q. Qian       04-17-1996      updated to version 1.2           */
/*                                                                       */
/*************************************************************************/
#define         NU_SOURCE_FILE


#include        "cs_extr.h"                 /* Common service functions  */
#include        "tc_extr.h"                 /* Thread control functions  */
#include        "io_extr.h"                 /* I/O driver functions      */
#include        "hi_extr.h"                 /* History functions         */

/* Define external inner-component global data references.  */

extern CS_NODE         *IOD_Created_Drivers_List;
extern UNSIGNED         IOD_Total_Drivers;
extern TC_PROTECT       IOD_List_Protect;



/*************************************************************************/
/*                                                                       */
/* FUNCTION                                                              */
/*                                                                       */
/*      IOC_Create_Driver                                                */
/*                                                                       */
/* DESCRIPTION                                                           */
/*                                                                       */
/*      This function creates an I/O driver and places it on the list of */
/*      created I/O drivers.  Note that this function does not actually  */
/*      invoke the driver.                                               */
/*                                                                       */
/* AUTHOR                                                                */
/*                                                                       */
/*      William E. Lamie, Accelerated Technology, Inc.                   */
/*                                                                       */
/* CALLED BY                                                             */
/*                                                                       */
/*      Application                                                      */
/*      IOCE_Create_Driver                  Error checking shell         */
/*                                                                       */
/* CALLS                                                                 */
/*                                                                       */
/*      CSC_Place_On_List                   Add node to linked-list      */
/*      [HIC_Make_History_Entry]            Make entry in history log    */
/*      [TCT_Check_Stack]                   Stack checking function      */
/*      TCT_Protect                         Data structure protect       */
/*      TCT_Unprotect                       Un-protect data structure    */
/*                                                                       */
/* INPUTS                                                                */
/*                                                                       */
/*      driver                              Driver control block pointer */
/*      name                                Driver's logical name        */
/*      driver_entry                        Driver's point of entry      */
/*                                                                       */
/* OUTPUTS                                                               */
/*                                                                       */
/*      NU_SUCCESS                                                       */
/*                                                                       */
/* HISTORY                                                               */
/*                                                                       */
/*         NAME            DATE                    REMARKS               */
/*                                                                       */
/*      W. Lamie        03-01-1993      Created initial version 1.0      */
/*      D. Lamie        04-19-1993      Verified version 1.0             */
/*                                                                       */
/*************************************************************************/
STATUS  IOC_Create_Driver(NU_DRIVER *driver, CHAR *name, 
                        VOID (*driver_entry)(NU_DRIVER *, NU_DRIVER_REQUEST *))
{

INT             i;                          /* Working index variable    */


#ifdef  NU_ENABLE_STACK_CHECK

    /* Call stack checking function to check for an overflow condition.  */
    TCT_Check_Stack();

#endif

#ifdef  NU_ENABLE_HISTORY

    /* Make an entry that corresponds to this function in the system history
       log.  */
    HIC_Make_History_Entry(NU_CREATE_DRIVER_ID, (UNSIGNED) driver, 
                                (UNSIGNED) name, (UNSIGNED) driver_entry);

#endif

    /* First, clear the driver ID just in case it is an old Driver
       Control Block.  */
    driver -> nu_driver_id =             0;
    
    /* Fill in the driver's name.  */
    for (i = 0; i < NU_MAX_NAME; i++)
        driver  -> nu_driver_name[i] =  name[i];    

    /* Save the driver's entry function in the control block.  */
    driver -> nu_driver_entry =  driver_entry;

    /* Protect against access to the list of created drivers.  */
    TCT_Protect(&IOD_List_Protect);
    
    /* At this point the driver  is completely built.  The ID can now be 
       set and it can be linked into the created driver  list.  */
    driver  -> nu_driver_id =           IO_DRIVER_ID;

    /* Link the driver  into the list of created I/O drivers and increment the
       total number of drivers in the system.  */
    CSC_Place_On_List(&IOD_Created_Drivers_List, (CS_NODE *) driver);
    IOD_Total_Drivers++;

    /* Release protection against access to the list of created I/O drivers. */
    TCT_Unprotect();

    /* Return successful completion.  */
    return(NU_SUCCESS);
}