table: Helps you implement a table.(3)

NAME
table: Helps you implement a table. - This handler helps you implement a table by doing some of the processing for you. More...

  Modules
table_iterator: The table iterator helper is designed to simplify the task of writing a table handler for the net-snmp agent when the data being accessed is not in an oid sorted form and must be accessed externally.
Functionally, it is a specialized version of the more generic table helper but easies the burden of GETNEXT processing by manually looping through all the data indexes retrieved through function calls which should be supplied by the module that wishes help.

table_data: Helps you implement a table with datamatted storage.
This helper helps you implement a table where all the indexes are expected to be stored within the agent itself and not in some external storage location.

table_array: Helps you implement a table when data can be stored locally. The data is stored in a sorted array, using a binary search for lookups.
The table_array handler is used (automatically) in conjuntion with the table handler.

  Functions
netsnmp_mib_handler * netsnmp_get_table_handler (netsnmp_table_registration_info *tabreq)
Given a netsnmp_table_registration_info object, creates a table handler.
int netsnmp_register_table (netsnmp_handler_registration *reginfo, netsnmp_table_registration_info *tabreq)
creates a table handler given the netsnmp_table_registration_info object, inserts it into the request chain and then calls netsnmp_register_handler() to register the table into the agent.
netsnmp_table_request_info * netsnmp_extract_table_info (netsnmp_request_info *request)
extracts the processed table information from a given request.
netsnmp_table_registration_info * netsnmp_find_table_registration_info (netsnmp_handler_registration *reginfo)
extracts the registered netsnmp_table_registration_info object from a netsnmp_handler_registration object.
int table_helper_handler (netsnmp_mib_handler *handler, netsnmp_handler_registration *reginfo, netsnmp_agent_request_info *reqinfo, netsnmp_request_info *requests)
implements the table helper handler.
int netsnmp_table_build_result (netsnmp_handler_registration *reginfo, netsnmp_request_info *reqinfo, netsnmp_table_request_info *table_info, u_char type, u_char *result, size_t result_len)
Builds the result to be returned to the agent given the table information.
int netsnmp_table_build_oid (netsnmp_handler_registration *reginfo, netsnmp_request_info *reqinfo, netsnmp_table_request_info *table_info)
given a registration info object, a request object and the table info object it builds the request->requestvb->name oid from the index values and column information found in the table_info object.
int netsnmp_table_build_oid_from_index (netsnmp_handler_registration *reginfo, netsnmp_request_info *reqinfo, netsnmp_table_request_info *table_info)
Builds an oid from index information.
int netsnmp_update_variable_list_from_index (netsnmp_table_request_info *tri)
parses an OID into table indexses.
int netsnmp_update_indexes_from_variable_list (netsnmp_table_request_info *tri)
builds an oid given a set of indexes.
int netsnmp_check_getnext_reply (netsnmp_request_info *request, oid *prefix, size_t prefix_len, netsnmp_variable_list *newvar, netsnmp_variable_list **outvar)
checks the original request against the current data being passed in if its greater than the request oid but less than the current valid return, set the current valid return to the new value.

DETAILED DESCRIPTION

This handler helps you implement a table by doing some of the processing for you.

This handler truly shows the power of the new handler mechanism. By creating a table handler and injecting it into your calling chain, or by using the netsnmp_register_table() function to register your table, you get access to some pre-parsed information. Specifically, the table handler pulls out the column number and indexes from the request oid so that you don't have to do the complex work to do that parsing within your own code.

To do this, the table handler needs to know up front how your table is structured. To inform it about this, you fill in a table_registeration_info structure that is passed to the table handler. It contains the asn index types for the table as well as the minimum and maximum column that should be used.

FUNCTION DOCUMENTATION

  int netsnmp_check_getnext_reply (netsnmp_request_info * request, oid * prefix, size_t prefix_len, netsnmp_variable_list * newvar, netsnmp_variable_list ** outvar)

checks the original request against the current data being passed in if its greater than the request oid but less than the current valid return, set the current valid return to the new value.

returns 1 if outvar was replaced with the oid from newvar (success). returns 0 if not.

Definition at line 563 of file table.c.

  netsnmp_table_request_info* netsnmp_extract_table_info (netsnmp_request_info * request) [inline]

extracts the processed table information from a given request.

call this from subhandlers on a request to extract the processed netsnmp_request_info information. The resulting information includes the index values and the column number.

Definition at line 92 of file table.c.

Referenced by netsnmp_table_data_helper_handler(), and netsnmp_table_data_set_helper_handler().

  netsnmp_table_registration_info* netsnmp_find_table_registration_info (netsnmp_handler_registration * reginfo)

extracts the registered netsnmp_table_registration_info object from a netsnmp_handler_registration object.

Definition at line 101 of file table.c.

Referenced by netsnmp_table_data_helper_handler().

  netsnmp_mib_handler* netsnmp_get_table_handler (netsnmp_table_registration_info * tabreq)

Given a netsnmp_table_registration_info object, creates a table handler.

You can use this table handler by injecting it into a calling chain. When the handler gets called, it'll do processing and store it's information into the request->parent_data structure.

Definition at line 56 of file table.c.

Referenced by netsnmp_register_table().

  int netsnmp_register_table (netsnmp_handler_registration * reginfo, netsnmp_table_registration_info * tabreq)

creates a table handler given the netsnmp_table_registration_info object, inserts it into the request chain and then calls netsnmp_register_handler() to register the table into the agent.

Definition at line 79 of file table.c.

Referenced by netsnmp_register_table_array(), and netsnmp_register_table_data().

  int netsnmp_table_build_oid (netsnmp_handler_registration * reginfo, netsnmp_request_info * reqinfo, netsnmp_table_request_info * table_info)

given a registration info object, a request object and the table info object it builds the request->requestvb->name oid from the index values and column information found in the table_info object.

Definition at line 488 of file table.c.

Referenced by netsnmp_table_build_result().

  int netsnmp_table_build_oid_from_index (netsnmp_handler_registration * reginfo, netsnmp_request_info * reqinfo, netsnmp_table_request_info * table_info)

Builds an oid from index information.

Definition at line 513 of file table.c.

  int netsnmp_table_build_result (netsnmp_handler_registration * reginfo, netsnmp_request_info * reqinfo, netsnmp_table_request_info * table_info, u_char type, u_char * result, size_t result_len)

Builds the result to be returned to the agent given the table information.

Use this function to return results from lowel level handlers to the agent. It takes care of building the proper resulting oid (containing proper indexing) and inserts the result value into the returning varbind.

Definition at line 456 of file table.c.

  int netsnmp_update_indexes_from_variable_list (netsnmp_table_request_info * tri)

builds an oid given a set of indexes.

Definition at line 548 of file table.c.

  int netsnmp_update_variable_list_from_index (netsnmp_table_request_info * tri)

parses an OID into table indexses.

Definition at line 540 of file table.c.

  int table_helper_handler (netsnmp_mib_handler * handler, netsnmp_handler_registration * reginfo, netsnmp_agent_request_info * reqinfo, netsnmp_request_info * requests)

implements the table helper handler.

Definition at line 109 of file table.c.