ospf_vs_lib.c

vxworks下ospf协议栈

/* ospf_vs_lib.c - ospf virtual stack management library */

/* Copyright 2000-2003 Wind River Systems, Inc. */

/*
modification history
--------------------
02c,02jun03,ram Changed native memory usage to OSPF memory partition
02b,29may03,agi Modified RWOS calls to OSPF calls as part of RWOS removal 
02a,08oct02,agi Fixed empty file compiler warning
02,17sep01,kc  Moved ospfConfigurationTableInit() from ospf_init.c.
01,07mar01jkw	 written.
*/

/*
DESCRIPTION

This module implements the framework for OSPF Virtual Stacks.  Each stack is
represented by an OSPF_GLOBAL_DATA structure defined in
target/src/wrn/ospf/ospf_vs_data.h.  Please see that file for information
on particular elements of that data structure.

The system is an array of pointers to these structures stored in vsOspfTbl and
indexed by an integer from 0 to OSPF_VSID_MAX.  There is a special stack, referred
to as the management stack, which is defined as VS_MGMT_STACK_OSPF.  This is
defined in target/src/wrn/ospf/ospf_vs_lib.h.

For tasks calling into the stack we provide a current Ospf Virtual Stack
number concept via a task variable called myTaskNum.  This variable can be
gotten or set via a set of routines in this module.  Routines called in the
context of a task (though NEVER tNetTask) it is possible to reference elements
of the stack's virtual stack like this:

.CS

ospfVsTbl[myTaskNum]->stackGlobalYouWantToLookAt
*/

/* this include is here to fix the "empty file" compiler warning */
#include "vxWorks.h"

/*
 * This huge ifdef means that the file gets run through the compiler but is
 * empty in the case where we're building the stack without 
 * __OSPF_VIRTUAL_STACK__ support.
 */

#ifdef __OSPF_VIRTUAL_STACK__

/* includes */
#include "ospf_vs_lib.h"
#include "ospf_vs_data.h"

/* defines */

/* globals */
int myStackNum = 0; /* Task local stack number. */
OSPF_GLOBAL_DATA* ospfVsTbl[OSPF_VSID_MAX];
SEM_ID ospfVsTblLock;
OSPF_VSID mgmtStackId;


/*******************************************************************************
*
* ospfVirtualStackLibInit - initialize the Ospf Virtual Stack system
*
* This routine initializes all the global data required by the ospf virtual stack
* system.
*
* RETURNS: OK or ERROR if any resources are unavailable.
*
*/

STATUS ospfVirtualStackLibInit
    (
    )
    {
    int count;

    /*
     * Create a semaphore to protect our table.
     */

    ospfVsTblLock = semBCreate(SEM_Q_PRIORITY, SEM_FULL);

    if (ospfVsTblLock == NULL)
        return (ERROR);

    for (count = 0; count < OSPF_VSID_MAX; count++)
        {
        ospfVsTbl[count] = NULL;
        }

    return (OK);
    }

/*******************************************************************************
*
* ospfVirtualStackCreate - creates an instance of an ospf virtual stack
*
* This routine creates an instance of a Ospf Virtual Stack and returns a pointer
* to the OSPF_VSID on successful completion.  Once this routine returns the
* desired initialization sequence may be called to start the appropriate
* protocols and initialize the network data structures.
*
* The stack index (i.e.  0 1 2 ...) is assigned.
*
* RETURNS: OK or ERROR. If ERROR is returned the <pOSPF_VSID> contents are
* not valid.
*
*/

STATUS ospfVirtualStackCreate
    (
    OSPF_VSID* pOSPF_VSID 		/* Buffer for storing virtual stack identifier */
    )
    {
    int ospfVsIndex, i;
    char tempName[OSPF_VS_NAME_MAX + 1];

    /* Lock out access until creation is complete or error is returned. */
    semTake(ospfVsTblLock, WAIT_FOREVER);

    /* Find the first empty slot. */

    for (ospfVsIndex = 0; ospfVsIndex < OSPF_VSID_MAX; ospfVsIndex++)
        {
        if (ospfVsTbl[ospfVsIndex] == NULL)
            break; /* Hey, we found one! */
        }

    if (ospfVsIndex == OSPF_VSID_MAX)
        {
        semGive(ospfVsTblLock);
        return (ERROR);
        }


        sprintf(tempName, "%d", ospfVsIndex);

    /* null-terminate it, just in case... */

    *(tempName + OSPF_VS_NAME_MAX) = EOS;

    /* Check that a stack with the same name doesn't already exist */
    for (i = 0; i < OSPF_VSID_MAX; i++)
        {
        if (ospfVsTbl[i] == NULL)  /* empty slot */
            continue;
        if (strcmp(ospfVsTbl[i]->pName, tempName) == 0)
            {
            semGive(ospfVsTblLock);
            return ERROR;
            }
        }

    /* Allocate our global structure.  */

    *pOSPF_VSID = ospfVsTbl[ospfVsIndex] = (OSPF_GLOBAL_DATA *)buffer_malloc
        (sizeof(OSPF_GLOBAL_DATA));

    if (ospfVsTbl[ospfVsIndex] == NULL)
        {
        semGive(ospfVsTblLock);
        return (ERROR);
        }

    /* Clear out the structure to NULL */
    memset ((char *)*pOSPF_VSID,0, sizeof(OSPF_GLOBAL_DATA));

    /*
     * Make the name the OSPF VS number.
     */

    ospfVsTbl[ospfVsIndex]->pName = (char *)&ospfVsTbl[ospfVsIndex]->name;

    memcpy(tempName, ospfVsTbl[ospfVsIndex]->pName, sizeof(tempName));

    semGive(ospfVsTblLock);

    return (OK);
    }

/*******************************************************************************
*
* ospfVirtualStackInit - initialize an ospf virtual stack
*
* This routine performs the default initialization of an OSPF Virtual stack
* created with the ospfVirtualStackCreate() routine. When this routine
* completes, the OSPF protocol will be initialized and
* the corresponding data structures for the stack will be valid.
*
* RETURNS: OK, or ERROR if initialization fails.
*/

STATUS ospfVirtualStackInit
    (
    OSPF_VSID ospfVsId	  /* Stack identifier from ospfVirtualStackCreate() routine */
    )
    {
    int ospfVsIndex;

     /* Verify stack identifier. Exit if not found. */

    semTake(ospfVsTblLock, WAIT_FOREVER);

    for (ospfVsIndex = 0; ospfVsIndex < OSPF_VSID_MAX; ospfVsIndex++)
        if (ospfVsTbl[ospfVsIndex] == ospfVsId)
            break;

    if (ospfVsIndex == OSPF_VSID_MAX)
        {
        semGive(ospfVsTblLock);
        return (ERROR);
        }

    semGive(ospfVsTblLock);

    return (OK);
    }

/*******************************************************************************
*
* ospfVirtualStackDelete - delete an ospf virtual stack
*
* This routine deletes the ospf virtual stack referenced by the OSPF_VSID passed to it.
*
* RETURNS: OK or ERROR if the OSPF_VSID passed to the call was in some way invalid
*
*/

STATUS ospfVirtualStackDelete
    (
    OSPF_VSID ospfVsId /* VID returned by virtualStackCreate */
    )
    {
    int ospfVsIndex;

    semTake(ospfVsTblLock, WAIT_FOREVER);

    for (ospfVsIndex = 0; ospfVsIndex < OSPF_VSID_MAX; ospfVsIndex++)
        if (ospfVsTbl[ospfVsIndex] == ospfVsId)
            break; /* Hey, we found it! */

    /* Check that we did find it. */
    if (ospfVsIndex == OSPF_VSID_MAX)
        {
        semGive(ospfVsTblLock);