local/mib2c.iterate.conf

## -*- c -*-
######################################################################
## Do the .h file
######################################################################
@open ${name}.h@
/*
 * Note: this file originally auto-generated by mib2c using
 *        $Id$
 */
#ifndef $name.uc_H
#define $name.uc_H

/* function declarations */
void init_$name(void);
@foreach $i table@
void initialize_table_$i(void);
Netsnmp_Node_Handler ${i}_handler;

Netsnmp_First_Data_Point  ${i}_get_first_data_point;
Netsnmp_Next_Data_Point   ${i}_get_next_data_point;
@end@
@foreach $i table@

/* column number definitions for table $i */
#include "${name}_columns.h"
@run mib2c.column_defines.conf@

/* enum definions */
#include "${name}_enums.h"
@run mib2c.column_enums.conf@

@end@ // foreach table

#endif /* $name.uc_H */
######################################################################
## Do the .c file
######################################################################
@open ${name}.c@
/*
 * Note: this file originally auto-generated by mib2c using
 *        $Id$
 */

#include <net-snmp/net-snmp-config.h>
#include <net-snmp/net-snmp-includes.h>
#include <net-snmp/agent/net-snmp-agent-includes.h>
#include "${name}.h"

@foreach $i table@
/** Initialize the $i table by defining its contents and how it's structured */
void
initialize_table_$i(void)
{
    static oid ${i}_oid[] = {$i.commaoid};
    netsnmp_table_registration_info *table_info;
    netsnmp_handler_registration *my_handler;
    netsnmp_iterator_info *iinfo;

    /** create the table registration information structures */
    table_info = SNMP_MALLOC_TYPEDEF(netsnmp_table_registration_info);
    iinfo = SNMP_MALLOC_TYPEDEF(netsnmp_iterator_info);

    /** if your table is read only, it's easiest to change the
        HANDLER_CAN_RWRITE definition below to HANDLER_CAN_RONLY */
    my_handler = netsnmp_create_handler_registration("$i",
                                             ${i}_handler,
                                             ${i}_oid,
                                             OID_LENGTH(${i}_oid),
                                             HANDLER_CAN_RWRITE);
            
    if (!my_handler || !table_info || !iinfo) {
        snmp_log(LOG_ERR, "malloc failed in initialize_table_$i");
        return; /* Serious error. */
    }

    /***************************************************
     * Setting up the table's definition
     */
    netsnmp_table_helper_add_indexes(table_info,
    @foreach $idx index@
                                  $idx.type, /* index: $idx */
    @end@
                             0);

    /** Define the minimum and maximum accessible columns.  This
        optimizes retrival. */
    @eval $minv = 0xffffffff@
    @eval $maxv = 0@
    @foreach $c column@
        @if $c.access =~ /(Read|Create)/@
          @eval $minv = min($minv, $c.subid)@
          @eval $maxv = max($maxv, $c.subid)@
        @end@
    @end@
    table_info->min_column = $minv;
    table_info->max_column = $maxv;

    /* iterator access routines */
    iinfo->get_first_data_point = ${i}_get_first_data_point;
    iinfo->get_next_data_point = ${i}_get_next_data_point;

    /** you may wish to set these as well */
#ifdef MAYBE_USE_THESE
    iinfo->make_data_context = ${i}_context_convert_function;
    iinfo->free_data_context = ${i}_data_free;

    /** pick *only* one of these if you use them */
    iinfo->free_loop_context = ${i}_loop_free;
    iinfo->free_loop_context_at_end = ${i}_loop_free;
#endif

    /** tie the two structures together */
    iinfo->table_reginfo = table_info;

    /***************************************************
     * registering the table with the master agent
     */
    DEBUGMSGTL(("initialize_table_$i",
                "Registering table $i as a table iterator\n"));		 
    netsnmp_register_table_iterator(my_handler, iinfo);
}
@end@ // foreach table

/** Initializes the $name module */
void
init_$name(void)
{

  /** here we initialize all the tables we're planning on supporting */
  @foreach $i table@
    initialize_table_$i();
  @end@
}
@foreach $i table@

/** returns the first data point within the $i table data.

    Set the my_loop_context variable to the first data point structure
    of your choice (from which you can find the next one).  This could
    be anything from the first node in a linked list, to an integer
    pointer containing the beginning of an array variable.

    Set the my_data_context variable to something to be returned to
    you later (in your main ${i}_handler routine) that will provide
    you with the data to return in a given row.  This could be the
    same pointer as what my_loop_context is set to, or something
    different.

    The put_index_data variable contains a list of snmp variable
    bindings, one for each index in your table.  Set the values of
    each appropriately according to the data matching the first row
    and return the put_index_data variable at the end of the function.
*/
netsnmp_variable_list *
${i}_get_first_data_point(void **my_loop_context, void **my_data_context,
                          netsnmp_variable_list *put_index_data,
                          netsnmp_iterator_info *mydata)
{

    netsnmp_variable_list *vptr;

    *my_loop_context = /** XXX */;
    *my_data_context = /** XXX */;

    vptr = put_index_data;
    
    @foreach $idx index@
    snmp_set_var_value(vptr, (u_char *) /** XXX: $idx data */, /** XXX: length of $idx data */);
    vptr = vptr->next_variable;
    @end@

    return put_index_data;
}

/** functionally the same as ${i}_get_first_data_point, but
   my_loop_context has already been set to a previous value and should
   be updated to the next in the list.  For example, if it was a
   linked list, you might want to cast it to your local data type and
   then return my_loop_context->next.  The my_data_context pointer
   should be set to something you need later (in your main
   ${i}_handler routine) and the indexes in put_index_data updated
   again. */
netsnmp_variable_list *
${i}_get_next_data_point(void **my_loop_context, void **my_data_context,
                         netsnmp_variable_list *put_index_data,
                         netsnmp_iterator_info *mydata)
{

    netsnmp_variable_list *vptr;

    *my_loop_context = /** XXX */;
    *my_data_context = /** XXX */;

    vptr = put_index_data;
    
    @foreach $idx index@
    snmp_set_var_value(vptr, (u_char *) /** XXX: $idx data */, /** XXX: length of $idx data */);
    vptr = vptr->next_variable;
    @end@

    return put_index_data;
}

/** handles requests for the $i table, if anything else needs to be done */
int
${i}_handler(
    netsnmp_mib_handler               *handler,
    netsnmp_handler_registration      *reginfo,
    netsnmp_agent_request_info        *reqinfo,
    netsnmp_request_info              *requests) {

    netsnmp_request_info *request;
    netsnmp_table_request_info *table_info;
    netsnmp_variable_list *var;
    
    for(request = requests; request; request = request->next) {
        var = request->requestvb;
        if (request->processed != 0)
            continue;

        /** perform anything here that you need to do before each
           request is processed. */

        /** the following extracts the my_data_context pointer set in
           the loop functions above.  You can then use the results to
           help return data for the columns of the $i table in question */
        /** XXX */ = (/** XXX */ *) netsnmp_extract_iterator_context(request);
        if (/** XXX */ == NULL) {
            if (reqinfo->mode == MODE_GET) {
                netsnmp_set_request_error(reqinfo, request, SNMP_NOSUCHINSTANCE);
                continue;
            }
            /** XXX: no row existed, if you support creation and this is a
               set, start dealing with it here, else continue */
        }

        /** extracts the information about the table from the request */
        table_info = netsnmp_extract_table_info(request);
        /** table_info->colnum contains the column number requested */
        /** table_info->indexes contains a linked list of snmp variable
           bindings for the indexes of the table.  Values in the list
           have been set corresponding to the indexes of the
           request */
        if (table_info==NULL) {
            continue;
        }

        switch(reqinfo->mode) {
            /** the table_iterator helper should change all GETNEXTs
               into GETs for you automatically, so you don't have to
               worry about the GETNEXT case.  Only GETs and SETs need
               to be dealt with here */
            case MODE_GET:
                switch(table_info->colnum) {
                    @foreach $c column@
                        @if $c.access =~ /(Read|Create)/@
                    case COLUMN_$c.uc:
                        snmp_set_var_typed_value(var, $c.type, (u_char *) /** XXX: column data */, /** XXX: column data length */);
                        break;

                        @end@
                    @end@
                    default:
                        /** We shouldn't get here */
                        snmp_log(LOG_ERR, "problem encountered in ${i}_handler: unknown column\n");
                }
                break;

            case MODE_SET_RESERVE1:
                /** set handling... */

            default:
                snmp_log(LOG_ERR, "problem encountered in ${i}_handler: unsupported mode\n");
        }
    }
    return SNMP_ERR_NOERROR;
}
@end@ // foreach table