#include <net-snmp/net-snmp-config.h>

#include <net-snmp/net-snmp-features.h>

#include <net-snmp/net-snmp-includes.h>

#include <net-snmp/agent/net-snmp-agent-includes.h>

netsnmp_feature_provide(stash_to_next);

netsnmp_feature_child_of(stash_to_next, mib_helpers);

#ifdef NETSNMP_FEATURE_REQUIRE_STASH_TO_NEXT

netsnmp_feature_require(oid_stash);

netsnmp_feature_require(oid_stash_add_data);

#endif

#ifndef NETSNMP_FEATURE_REMOVE_STASH_TO_NEXT

#include <net-snmp/agent/stash_to_next.h>

#include <net-snmp/agent/stash_cache.h>

/** @defgroup stash_to_next stash_to_next

 *  Convert GET_STASH requests into GETNEXT requests for the handler.

 *  The purpose of this handler is to convert a GET_STASH auto-cache request

 *  to a series of GETNEXT requests.  It can be inserted into a handler chain

 *  where the lower-level handlers don't process such requests themselves.

 *  @ingroup utilities

 *  @{

 */

/** returns a stash_to_next handler that can be injected into a given

 *  handler chain.

 */

netsnmp_mib_handler *

netsnmp_get_stash_to_next_handler(void)

{

    netsnmp_mib_handler *handler =

        netsnmp_create_handler("stash_to_next",

                               netsnmp_stash_to_next_helper);

    if (NULL != handler)

        handler->flags |= MIB_HANDLER_AUTO_NEXT;

    return handler;

}

/** @internal Implements the stash_to_next handler */

int

netsnmp_stash_to_next_helper(netsnmp_mib_handler *handler,

                            netsnmp_handler_registration *reginfo,

                            netsnmp_agent_request_info *reqinfo,

                            netsnmp_request_info *requests)

{

    int             ret = SNMP_ERR_NOERROR;

    int             namelen;

    int             finished = 0;

    netsnmp_oid_stash_node **cinfo;

    netsnmp_variable_list   *vb;

    netsnmp_request_info    *reqtmp;

    /*

     * this code depends on AUTO_NEXT being set

     */

    netsnmp_assert(handler->flags & MIB_HANDLER_AUTO_NEXT);

    /*

     * Don't do anything for any modes except GET_STASH. Just return,

     * and the agent will call the next handler (AUTO_NEXT).

     *

     * If the handler chain already supports GET_STASH, we don't

     * need to do anything here either.  Once again, we just return

     * and the agent will call the next handler (AUTO_NEXT).

     *

     * Otherwise, we munge the mode to GET_NEXT, and call the

     * next handler ourselves, repeatedly until we've retrieved the

     * full contents of the table or subtree.

     *   Then restore the mode and return to the calling handler 

     * (setting AUTO_NEXT_OVERRRIDE so the agent knows what we did).

     */

    if (MODE_GET_STASH == reqinfo->mode) {

        if ( reginfo->modes & HANDLER_CAN_STASH ) {

            return ret;

        }

        cinfo  = netsnmp_extract_stash_cache( reqinfo );

        reqtmp = SNMP_MALLOC_TYPEDEF(netsnmp_request_info);

        vb = reqtmp->requestvb = SNMP_MALLOC_TYPEDEF( netsnmp_variable_list );

        vb->type = ASN_NULL;

        snmp_set_var_objid( vb, reginfo->rootoid, reginfo->rootoid_len );

        reqinfo->mode = MODE_GETNEXT;

        while (!finished) {

            ret = netsnmp_call_next_handler(handler, reginfo, reqinfo, reqtmp);

            namelen = SNMP_MIN(vb->name_length, reginfo->rootoid_len);

            if ( !snmp_oid_compare( reginfo->rootoid, reginfo->rootoid_len,

                                   vb->name, namelen) &&

                 vb->type != ASN_NULL && vb->type != SNMP_ENDOFMIBVIEW ) {

                /*

                 * This result is relevant so save it, and prepare

                 * the request varbind for the next query.

                 */

                netsnmp_oid_stash_add_data( cinfo, vb->name, vb->name_length,

                                            snmp_clone_varbind( vb ));

                    /*

                     * Tidy up the response structure,

                     *  ready for retrieving the next entry

                     */

                netsnmp_free_all_list_data(reqtmp->parent_data);

                reqtmp->parent_data = NULL;

                reqtmp->processed = 0;

                vb->type = ASN_NULL;

            } else {

                finished = 1;

            }

        }

        reqinfo->mode = MODE_GET_STASH;

        /*

         * let the handler chain processing know that we've already

         * called the next handler

         */

        handler->flags |= MIB_HANDLER_AUTO_NEXT_OVERRIDE_ONCE;

    }

    return ret;

}

/**  @} */

#else  /* ! NETSNMP_FEATURE_REMOVE_STASH_TO_NEXT */

netsnmp_feature_unused(stash_to_next);

#endif /* ! NETSNMP_FEATURE_REMOVE_STASH_TO_NEXT */