/* snsRtpHook.c - Socket Name Service hook for RTP deletion */

/*
 * Copyright (c) 2004-2007, 2009, 2011, 2013 Wind River Systems, Inc.
 *
 * The right to copy, distribute, modify or otherwise make use
 * of this software may be licensed only pursuant to the terms
 * of an applicable Wind River license agreement.
 */

/*
modification history
--------------------
01g,16sep13,f_f  fix static overrun (WIND00435182)
01f,19jul11,shi  LP64 conversion
01e,03dec09,cww  Moved rtp funcbind pointers
01d,20jun07,ebh  remove unnecessary variable taskId in snsRtpHookInit
01c,08mar06,ebh  correct typo as per code review
01b,12jan05,bwa  added check for presence of RTP hooks (SPR105673).
01a,02sep04,ymz  created (moved from snsLib.c)
*/

/*
DESCRIPTION

This file contains routines to invoke socket name service (SNS) to
cleanup service records when the RTP where the service resides is deleted.

During the SNS initialization, SNS adds a routine to the RTP delete hook.
The initialization process preallocates a socket used by SNS to receive RTP
delete events. 
When a RTP is deleted, the SNS hook is invoked. The routine  sends an 
asynchronous message to the SNS server asking for cleanup.

The routines in this file runs in the kernel, no matter whether the SNS
server is running in the kernel or in a RTP.

\NOMANUAL
*/

/* includes */

#include <vxWorks.h>
#include <rtpLibCommon.h>
#include <stdio.h>
#include <taskLib.h>
#include <sockLib.h>
#include <private/rtpLibP.h>
#include <dsi/private/salClientP.h>
#include <dsi/private/snsLibP.h>

/* locals */

LOCAL int snsCleanUpSockFd;       /* socket to sns server to request cleanup */

/* forward declarations */

LOCAL void snsCleanupRtnInit (void);
LOCAL void snsCleanupHook (const RTP_ID rtpId, const int exitCode);


/*******************************************************************************
*
* snsRtpHookInit - initialize the cleanup mechanism
*
* This function initializes the cleanup mechanism. A task is spawned so the
* vxWorks system initialization process does not get delayed.
*
* RETURNS: OK if initialization completes, ERROR otherwise.
*
* \NOMANUAL
*/

STATUS snsRtpHookInit
    (
    int         pri                 /* task priority */
    )
    {
    if (_func_rtpDeleteHookAdd == NULL)
        {
        printf ("Can't initialize SNS cleanup subsystem.\n"
                "RTP hooks not present in the system.\n");
        return (ERROR);
        }

    if((taskSpawn ("tSnsCleanupInit",
                    pri,        /* priority */
                    0,          /* task options */
                    20000,      /* stack space */
                    (FUNCPTR) snsCleanupRtnInit,
                    0, 0, 0, 0, 0, 0, 0, 0, 0, 0 )) == TASK_ID_ERROR)
        {
        printf(" Cannot spawn SNS cleanup init task...\n");
        return ERROR;
        }
    return OK;
    }

/*******************************************************************************
*
* snsCleanupRtnInit - initializes SNS cleanup hook
*
* This routine initializes SNS cleanup mechanism by setting up RTP
* deletion hook and attaching a connection to the SNS server.
*
* RETURNS: OK if the initialization is successful, ERROR otherwise.
*
* \NOMANUAL
*/

LOCAL void snsCleanupRtnInit (void)
    {
    int                i;    /* number of attempts attaching to SNS server */

    if ( _func_rtpHandleIdGet == NULL)
        {
        printf(" SNS cleanup init failed...\n");
        return;
        }

    for (i=0; i<SNS_INIT_RETRY; i++)
        {
       
        /* wait if sns server is not started yet */

        if ((snsCleanUpSockFd = salSnsClientCreate ()) <0)
            taskDelay (SNS_INIT_TIMEOUT*10);
        else
            {
            if (_func_rtpDeleteHookAdd (snsCleanupHook, FALSE) != OK)
                {
                salSnsClientDelete (snsCleanUpSockFd);
                snsCleanUpSockFd = -1;
                printf(" Cannot install SNS cleanup hook...\n");
                return;
                }

            /* snsCleanUpSockFd remains opened, no close mechanism 
             * see comments in snsCleanupHook routine
             */

            return;
            }
        }

    printf(" SNS cleanup init failed...\n");

    return;
    }

/*******************************************************************************
*
* snsCleanupHook  - notify SNS server a rtp is being deleted.
*
* This routine notifies SNS server that a RTP is being deleted.
*
* RETURNS: N/A.
*
* \NOMANUAL
*/

LOCAL void snsCleanupHook
    (
    const RTP_ID   rtpId,     /* rtp being deleted */
    const int      exitCode
    )

    {
    SNS_SERV_CLEANUP_MSG   msg;

    msg.cmd = SNS_CMD_CLEANUP;
    msg.rtpId = (long) _func_rtpHandleIdGet (rtpId);

    (void) send (snsCleanUpSockFd, (void *) &msg, sizeof (SNS_SERV_CLEANUP_MSG), 
          MSG_DONTWAIT);

    /* we do not check if send is fails, just keep sending 
     * the alternative is to close the socket and remove delete hook,
     * but it is not safe to delete the hook within the hook routine (the
     * next hook in the hook array may get skipped to call), 
     * so we take the policy of doing nothing.
     */

    return;
    }