NET-SNMP кодирование, помогите с реализацией таблицы.

Oops 0

2 июня, 2011

Опубликовано 2 июня, 2011 (изменено) · Жалоба

Здрасти, здрасти!!!

Имеется ОС Linux на которой поднят SNMP демон ( snmpd ). Я пишу библиотеку, которую подключает snmpd при старте и используя которую реагирует на команды. Библиотеку пишу на обычном С, пользуюсь помощью тут: http://www.net-snmp.org/wiki/index.php/TUT...oding_Tutorials .

Понадобилось написать SNMP таблицу в кторой надо менять переменные.

Работать с таблицей состоящей из одной строки - просто, вот пример:

   static oid ipConfTable_registration_oid[] = { 1, 3, 6, 1, 4, 1, 1958, 7, 2, 2, 3 };    // прикрепляем к таблици OID.
   int ipConfTable_handler (netsnmp_mib_handler *handler,netsnmp_handler_registration *reginfo,netsnmp_agent_request_info *reqinfo,netsnmp_request_info *requests);  // объявляем функцию-обработчик обытий таблицы

/// TABLE    ///

       {
            netsnmp_table_data_set *table_set;
            netsnmp_table_row *row;

            table_set = netsnmp_create_table_data_set("Table");

            table_set->allow_creation = 1;

            netsnmp_table_dataset_add_index(table_set, ASN_OCTET_STR);

            netsnmp_table_set_multi_add_default_row(table_set,  // таблица из 5 колонок

                                                    1, ASN_IPADDRESS, 1, NULL, 0,
                                                    2, ASN_INTEGER, 1, NULL, 0,

                                                    3, ASN_IPADDRESS, 1, NULL, 0,
                                                    4, ASN_OCTET_STR, 1, NULL, 0,
                                                    5, ASN_IPADDRESS, 1, NULL, 0,
                                                    0  );

            netsnmp_register_table_data_set(netsnmp_create_handler_registration
                                            ("Table",//NULL,
                                             ipConfTable_handler // прикрепляем фукцию обработчик,
                                             ipConfTable_registration_oid,
                                             OID_LENGTH(ipConfTable_registration_oid),
                                             HANDLER_CAN_RWRITE), table_set, NULL);


            row = netsnmp_create_table_data_row();


            int index;
            index = 0;
            netsnmp_table_row_add_index(row, ASN_INTEGER, &index, sizeof(index));

            ipConfAddress = 0x00000000;
            netsnmp_set_row_column(row, 1, ASN_IPADDRESS,(char*)&ipConfAddress, sizeof(ipConfAddress));
            netsnmp_mark_row_column_writable(row, 1, 1);

            unsigned int num = 1;
            netsnmp_set_row_column(row, 2, ASN_INTEGER,(char*)&num, sizeof(num));
            netsnmp_mark_row_column_writable(row, 2, 1);       

            u_long ipConfNetMask = 0x00000000;
            netsnmp_set_row_column(row, 3, ASN_IPADDRESS, (char*)&ipConfNetMask,sizeof(ipConfNetMask));
            netsnmp_mark_row_column_writable(row, 3, 1);        

            netsnmp_set_row_column(row, 4, ASN_OCTET_STR, "eth0",strlen("eth0"));
            netsnmp_mark_row_column_writable(row, 4, 1);        

            u_long gateway = 0x00000000;
            netsnmp_set_row_column(row, 5, ASN_IPADDRESS, (char*)&gateway,sizeof(gateway));
            netsnmp_mark_row_column_writable(row, 5, 1);        

            netsnmp_table_dataset_add_row(table_set, row);

            netsnmp_register_auto_data_table(table_set, NULL);

       }

Далее в функции обработчике производим запись и чтение значений таблицы.

int ipConfTable_handler(netsnmp_mib_handler *handler,netsnmp_handler_registration *reginfo,netsnmp_agent_request_info *reqinfo,netsnmp_request_info *requests)
{
        
        u_long         *ipConfAddress_cache = NULL;
        u_long         *ipConfNetMask_cache = NULL;
        u_long         *gateway_cache = NULL;

        netsnmp_variable_list *var;

        long int ret;
        netsnmp_request_info       *request;
        netsnmp_table_request_info *table_info;
        long int  variable;
        char i;

        for (request=requests; request; request=request->next) {
        
        var = request->requestvb;
        
        netsnmp_extract_iterator_context(request);
        table_info = netsnmp_extract_table_info(request);

        switch (reqinfo->mode) {
        
            case MODE_GET:

                    if(key == 0){   readConfigEthernet(); key = 1;}

                        switch (table_info->colnum) {
                        case 1:
                            snmp_set_var_typed_value(var, ASN_IPADDRESS,(u_char *) &ipConfAddress,sizeof( TYPE ));
                            break;
                        case 2:
                            break;
                        case 3:
                            snmp_set_var_typed_value(var, ASN_IPADDRESS,(u_char *) &ipConfNetMask,sizeof( TYPE ));
                            break;
                        case 4:
                            break;
                        case 5:
                            snmp_set_var_typed_value(var, ASN_IPADDRESS,(u_char *) &gateway,sizeof( TYPE ));
                            break;
                        default:
                            break;
                        }

                    break;

                 case MODE_SET_RESERVE1:

                        switch (table_info->colnum) {
                        case 1:
                            if (requests->requestvb->type != ASN_IPADDRESS) {

                    netsnmp_set_request_error(reqinfo, requests,SNMP_ERR_WRONGTYPE);

                        return SNMP_ERR_WRONGTYPE;
                            }
                            break;
                        case 3:
                           if (requests->requestvb->type != ASN_IPADDRESS) {

                    netsnmp_set_request_error(reqinfo, requests,SNMP_ERR_WRONGTYPE);

                        return SNMP_ERR_WRONGTYPE;
                            }
                            break;
                        case 5:
                       
                            if (requests->requestvb->type != ASN_IPADDRESS) {

                    netsnmp_set_request_error(reqinfo, requests,SNMP_ERR_WRONGTYPE);

                        return SNMP_ERR_WRONGTYPE;
                            }
                            break;
                        default:
                       
                            break;
                        }
     

                    break;

    case MODE_SET_RESERVE2:

                       switch (table_info->colnum) {
                        case 1:
                            memdup((u_char **) & ipConfAddress_cache, (u_char *) & ipConfAddress, sizeof(ipConfAddress));

                            if (ipConfAddress_cache == NULL) {
                                netsnmp_set_request_error(reqinfo, requests,SNMP_ERR_RESOURCEUNAVAILABLE);
                return SNMP_ERR_RESOURCEUNAVAILABLE;
                            }

                            netsnmp_request_add_list_data(requests,netsnmp_create_data_list(DELAYED_INSTANCE_SET_NAME,ipConfAddress_cache, free));
           
                            break;
                        case 3:
                            memdup((u_char **) & ipConfNetMask_cache, (u_char *) & ipConfNetMask, sizeof(ipConfNetMask));

                            if (ipConfNetMask_cache == NULL) {
                                netsnmp_set_request_error(reqinfo, requests,SNMP_ERR_RESOURCEUNAVAILABLE);
                return SNMP_ERR_RESOURCEUNAVAILABLE;
                            }

                            netsnmp_request_add_list_data(requests,netsnmp_create_data_list(DELAYED_INSTANCE_SET_NAME,ipConfNetMask_cache, free));
                            break;
                        case 5:
                            memdup((u_char **) & gateway_cache, (u_char *) & gateway, sizeof(gateway));

                            if (gateway_cache == NULL) {
                                netsnmp_set_request_error(reqinfo, requests,SNMP_ERR_RESOURCEUNAVAILABLE);
                return SNMP_ERR_RESOURCEUNAVAILABLE;
                            }

                            netsnmp_request_add_list_data(requests,netsnmp_create_data_list(DELAYED_INSTANCE_SET_NAME,gateway_cache, free));
                            break;
                        default:
                            break;
                        }
                   break;

        case MODE_SET_ACTION:

                              
                    variable = 0;

                        switch (table_info->colnum) {
                        case 1:

                            ipConfAddress = *(requests->requestvb->val.integer);

                            break;
                        case 3:
                            ipConfNetMask = *(requests->requestvb->val.integer);

                            break;
                        case 5:
                            gateway = *(requests->requestvb->val.integer);
                            break;
                        default:
                            break;
                      }
                    
                break;

    case MODE_SET_UNDO:

                        switch (table_info->colnum) {
                        case 1:
                            ipConfAddress = *((u_long *) netsnmp_request_get_list_data(requests,DELAYED_INSTANCE_SET_NAME));
                            break;
                        case 3:
                            ipConfNetMask = *((u_long *) netsnmp_request_get_list_data(requests,DELAYED_INSTANCE_SET_NAME));
                            break;
                        case 5:
                            gateway = *((u_long *) netsnmp_request_get_list_data(requests,DELAYED_INSTANCE_SET_NAME));
                            break;
                        default:
    
                            break;
     
                    }

                break;


        case MODE_SET_COMMIT:
                    
        case MODE_SET_FREE:

            break;

    }
        }
    return SNMP_ERR_NOERROR;
}

Подскажите как создать таблицу из нескольких строк?

Как определить индекс строки к которой обратились из вне?

Как создавать и удалять строки в таблице?

Буду благодарен за простой понятный для новичка код на С.

Помогите пожалуйста...

Изменено 2 июня, 2011 пользователем Oops