www.pudn.com > Demo C.rar > intdisc.c

/*
 * File:  intDisconnect.c
 * Date:  September 1996
 *
 * Description:
 * -----------
 * This function un-installs an interrupt service routine on a Tornado/PPC board
 *
 */

#include 
#include 
#include 
#include 
#include 
#include 
#include 


/*
#include 
*/
typedef struct intHandlerDesc           /* interrupt handler desciption */
    {
    VOIDFUNCPTR                 vec;    /* interrupt vector */
    int                         arg;    /* interrupt handler argument */
    struct intHandlerDesc *     next;   /* next interrupt handler & argument */
    } INT_HANDLER_DESC;


extern sysIntTbl[];
extern sysVmeIntTable[];
STATUS intDisconnect();
LOCAL int handlerDelete();

/******************************************************************************
 *
 * intDisconnect - un-install an ISR
 *
 * This routine un-installs an ISR from the interrupt vector table used by
 * the local and VMEbus interrupt dispatchers.
 *
 *****************************************************************************/

STATUS
intDisconnect(int vector)
{

  INT_HANDLER_DESC *handler;

  if (vector < 16)
    {
      printf("ERROR: cannot disconnect a local bus ISR with intDisconnect\n");
      return(ERROR);
    }
  if (vector > 255)
    {
      printf("ERROR: interrupt vector out of range\n");
      return(ERROR);
    }

  handler = (INT_HANDLER_DESC *)sysIntTbl[(int)vector];

  if (handler != NULL)
    {
      printf("disconnecting vector %d \n", vector);

      handlerDelete(handler);
      sysIntTbl[(int)vector] = NULL;

    }
  return(OK);

}

/******************************************************************************
 *
 * handlerDelete() - recursively deletes ISRs from sysIntTbl vector
 *
 *****************************************************************************/

LOCAL int
handlerDelete(INT_HANDLER_DESC *handler)
{
  if (handler->next != NULL)
    {
      handlerDelete(handler->next);
    }

  free(handler);
  handler = NULL;

  return(OK);

}