userapps/opensource/net-snmp/agent/helpers/bulk_to_next.c

   1 #include <net-snmp/net-snmp-config.h>
   2
   3 #if HAVE_STRING_H
   4 #include <string.h>
   5 #else
   6 #include <strings.h>
   7 #endif
   8
   9 #include <net-snmp/net-snmp-includes.h>
  10 #include <net-snmp/agent/net-snmp-agent-includes.h>
  11
  12 #include <net-snmp/agent/bulk_to_next.h>
  13
  14 #if HAVE_DMALLOC_H
  15 #include <dmalloc.h>
  16 #endif
  17
  18 /** @defgroup bulk_to_next bulk_to_next: convert GETBULK requests into GETNEXT requests for the handler.
  19  *  The only purpose of this handler is to convert a GETBULK request
  20  *  to a GETNEXT request.  It is inserted into handler chains where
  21  *  the handler has not set the HANDLER_CAN_GETBULK flag.
  22  *  @ingroup handler
  23  *  @{
  24  */
  25
  26 /** returns a bulk_to_next handler that can be injected into a given
  27  *  handler chain.
  28  */
  29 netsnmp_mib_handler *
  30 netsnmp_get_bulk_to_next_handler(void)
  31 {
  32     return netsnmp_create_handler("bulk_to_next",
  33                                   netsnmp_bulk_to_next_helper);
  34 }
  35
  36 /** takes answered requests and decrements the repeat count and
  37  *  updates the requests to the next to-do varbind in the list */
  38 void
  39 netsnmp_bulk_to_next_fix_requests(netsnmp_request_info *requests)
  40 {
  41     netsnmp_request_info *request;
  42     /*
  43      * update the varbinds for the next request series
  44      */
  45     for (request = requests; request; request = request->next) {
  46         if (request->repeat > 0 &&
  47             request->requestvb->type != ASN_NULL &&
  48             request->requestvb->type != ASN_PRIV_RETRY) {
  49             request->repeat--;
  50             snmp_set_var_objid(request->requestvb->next_variable,
  51                                request->requestvb->name,
  52                                request->requestvb->name_length);
  53             request->requestvb = request->requestvb->next_variable;
  54             request->requestvb->type = ASN_PRIV_RETRY;
  55         }
  56     }
  57 }
  58
  59 /** @internal Implements the bulk_to_next handler */
  60 int
  61 netsnmp_bulk_to_next_helper(netsnmp_mib_handler *handler,
  62                             netsnmp_handler_registration *reginfo,
  63                             netsnmp_agent_request_info *reqinfo,
  64                             netsnmp_request_info *requests)
  65 {
  66
  67     int             ret;
  68
  69     switch (reqinfo->mode) {
  70
  71     case MODE_GETBULK:
  72         reqinfo->mode = MODE_GETNEXT;
  73         ret =
  74             netsnmp_call_next_handler(handler, reginfo, reqinfo, requests);
  75         reqinfo->mode = MODE_GETBULK;
  76
  77         /*
  78          * update the varbinds for the next request series
  79          */
  80         netsnmp_bulk_to_next_fix_requests(requests);
  81         return ret;
  82
  83     default:
  84         return netsnmp_call_next_handler(handler, reginfo, reqinfo,
  85                                          requests);
  86     }
  87     return SNMP_ERR_GENERR;     /* should never get here */
  88 }
  89
  90 /** initializes the bulk_to_next helper which then registers a bulk_to_next
  91  *  handler as a run-time injectable handler for configuration file
  92  *  use.
  93  */
  94 void
  95 netsnmp_init_bulk_to_next_helper(void)
  96 {
  97     netsnmp_register_handler_by_name("bulk_to_next",
  98                                      netsnmp_get_bulk_to_next_handler());
  99 }