table_array(3) net-snmp table_array(3)
NAME
table_array - Helps you implement a table when data can be stored
locally.
Functions
int netsnmp_table_container_register (netsnmp_handler_registration
*reginfo, netsnmp_table_registration_info *tabreg,
netsnmp_table_array_callbacks *cb, netsnmp_container *container,
int group_rows)
register specified callbacks for the specified table/oid.
int netsnmp_table_array_register (netsnmp_handler_registration
*reginfo, netsnmp_table_registration_info *tabreg,
netsnmp_table_array_callbacks *cb, netsnmp_container *container,
int group_rows)
netsnmp_mib_handler * netsnmp_find_table_array_handler
(netsnmp_handler_registration *reginfo)
find the handler for the table_array helper.
netsnmp_container * netsnmp_extract_array_context (netsnmp_request_info
*request)
find the context data used by the table_array helper
int netsnmp_table_array_check_row_status (netsnmp_table_array_callbacks
*cb, netsnmp_request_group *ag, long *rs_new, long *rs_old)
this function is called to validate RowStatus transitions.
Detailed Description
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. It is primarily intended to be used with the mib2c
configuration file mib2c.array-user.conf.
The code generated by mib2c is useful when you have control of the data
for each row. If you cannot control when rows are added and deleted (or
at least be notified of changes to row data), then this handler is
probably not for you.
This handler makes use of callbacks (function pointers) to handle
various tasks. Code is generated for each callback, but will need to be
reviewed and flushed out by the user.
NOTE NOTE NOTE: Once place where mib2c is somewhat lacking is with
regards to tables with external indices. If your table makes use of one
or more external indices, please review the generated code very
carefully for comments regarding external indices.
NOTE NOTE NOTE: This helper, the API and callbacks are still being
tested and may change.
The generated code will define a structure for storage of table related
data. This structure must be used, as it contains the index OID for the
row, which is used for keeping the array sorted. You can add addition
fields or data to the structure for your own use.
The generated code will also have code to handle SNMP-SET processing.
If your table does not support any SET operations, simply comment out
the #define <PREFIX>_SET_HANDLING (where <PREFIX> is your table name)
in the header file.
SET processing modifies the row in-place. The duplicate_row callback
will be called to save a copy of the original row. In the event of a
failure before the commite phase, the row_copy callback will be called
to restore the original row from the copy.
Code will be generated to handle row creation. This code may be
disabled by commenting out the #define <PREFIX>_ROW_CREATION in the
header file.
If your table contains a RowStatus object, by default the code will not
allow object in an active row to be modified. To allow active rows to
be modified, remove the comment block around the #define
<PREFIX>_CAN_MODIFY_ACTIVE_ROW in the header file.
Code will be generated to maintain a secondary index for all rows,
stored in a binary tree. This is very useful for finding rows by a key
other than the OID index. By default, the functions for maintaining
this tree will be based on a character string. NOTE: this will likely
be made into a more generic mechanism, using new callback methods, in
the near future.
The generated code contains many TODO comments. Make sure you check
each one to see if it applies to your code. Examples include checking
indices for syntax (ranges, etc), initializing default values in newly
created rows, checking for row activation and deactivation
requirements, etc.
Function Documentation
netsnmp_container* netsnmp_extract_array_context (netsnmp_request_info *
request)
find the context data used by the table_array helper
Definition at line 229 of file table_array.c.
References netsnmp_request_get_list_data().
netsnmp_mib_handler* netsnmp_find_table_array_handler
(netsnmp_handler_registration * reginfo)
find the handler for the table_array helper.
Definition at line 212 of file table_array.c.
References netsnmp_mib_handler_s::access_method,
netsnmp_handler_registration_s::handler, netsnmp_mib_handler_s::next,
and NULL.
int netsnmp_table_array_check_row_status (netsnmp_table_array_callbacks *
cb, netsnmp_request_group * ag, long * rs_new, long * rs_old)
this function is called to validate RowStatus transitions.
Definition at line 236 of file table_array.c.
References netsnmp_table_array_callbacks_s::can_activate,
netsnmp_table_array_callbacks_s::can_deactivate,
netsnmp_table_array_callbacks_s::can_delete,
netsnmp_request_group_s::existing_row, NULL,
netsnmp_request_group_s::row_deleted, and
netsnmp_request_group_s::undo_info.
int netsnmp_table_container_register (netsnmp_handler_registration *
reginfo, netsnmp_table_registration_info * tabreg,
netsnmp_table_array_callbacks * cb, netsnmp_container * container, int
group_rows)
register specified callbacks for the specified table/oid.
If the group_rows parameter is set, the row related callbacks will be
called once for each unique row index. Otherwise, each callback will be
called only once, for all objects.
Definition at line 149 of file table_array.c.
References netsnmp_table_array_callbacks_s::can_set,
table_container_data_s::cb, netsnmp_container_s::compare,
netsnmp_table_array_callbacks_s::delete_row,
netsnmp_table_array_callbacks_s::duplicate_row,
netsnmp_handler_registration_s::handler, netsnmp_mib_handler_s::myvoid,
netsnmp_container_s::ncompare, netsnmp_register_table(), NULL,
netsnmp_table_array_callbacks_s::row_copy, snmp_log(),
SNMP_MALLOC_TYPEDEF, table_container_data_s::table, and
table_container_data_s::tblreg_info.
Referenced by netsnmp_table_array_register().
Version 5.4.2 5 Sep 2008 table_array(3)
Mac OS X 10.6 - Generated Thu Sep 17 20:21:45 CDT 2009