table_dataset.c

开发snmp的开发包有两个开放的SNMP开发库

     * loop through indexes and add types 
     */
    for (index = tp->indexes; index; index = index->next) {
        if (!snmp_parse_oid(index->ilabel, name, &name_length) ||
            (NULL ==
             (indexnode = get_tree(name, name_length, get_tree_head())))) {
            config_pwarn("can't instatiate table since "
                         "I don't know anything about one index");
            snmp_log(LOG_WARNING, "  index %s not found in tree\n",
                     index->ilabel);
            return;             /* xxx mem leak */
        }
            
        type = mib_to_asn_type(indexnode->type);
        if (type == (u_char) - 1) {
            config_pwarn("unknown index type");
            return;             /* xxx mem leak */
        }
        /*
         * if implied, mark it as such. also mark fixed length
         * octet strings as implied (ie no length prefix) as well.
         * */
        if ((TYPE_OCTETSTR == indexnode->type) &&  /* octet str */
            (NULL != indexnode->ranges) &&         /* & has range */
            (NULL == indexnode->ranges->next) &&   /*   but only one */
            (indexnode->ranges->high ==            /*   & high==low */
             indexnode->ranges->low)) {
            type |= ASN_PRIVATE;
            fixed_len = indexnode->ranges->high;
        }
        else if (index->isimplied)
            type |= ASN_PRIVATE;
        
        DEBUGMSGTL(("table_set_add_table",
                    "adding default index of type %d\n", type));
        netsnmp_table_dataset_add_index(table_set, type);

        /*
         * hack alert: for fixed lenght strings, save the
         * lenght for use during oid parsing.
         */
        if (fixed_len) {
            /*
             * find last (just added) index
             */
            netsnmp_variable_list *var =  table_set->table->indexes_template;
            while (NULL != var->next_variable)
                var = var->next_variable;
            var->val_len = fixed_len;
        }
    }
}
/** @internal */
void
netsnmp_config_parse_table_set(const char *token, char *line)
{
    oid             table_name[MAX_OID_LEN];
    size_t          table_name_length = MAX_OID_LEN;
    struct tree    *tp;
    netsnmp_table_data_set *table_set;
    data_set_tables *tables;
    unsigned int    mincol = 0xffffff, maxcol = 0;
    char           *pos;

    /*
     * instatiate a fake table based on MIB information 
     */
    DEBUGMSGTL(("9:table_set_add_table", "processing '%s'\n", line));
    if (NULL != (pos = strchr(line,' '))) {
        config_pwarn("ignoring extra tokens on line");
        snmp_log(LOG_WARNING,"  ignoring '%s'\n", pos);
        *pos = '\0';
    }

    /*
     * check for duplicate table
     */
    tables = (data_set_tables *) netsnmp_get_list_data(auto_tables, line);
    if (NULL != tables) {
        config_pwarn("duplicate table definition");
        return;
    }

    /*
     * parse oid and find tree structure
     */
    if (!snmp_parse_oid(line, table_name, &table_name_length)) {
        config_pwarn
            ("can't instatiate table since I can't parse the table name");
        return;
    }
    if(NULL == (tp = get_tree(table_name, table_name_length,
                              get_tree_head()))) {
        config_pwarn("can't instatiate table since "
                     "I can't find mib information about it");
        return;
    }

    if (NULL == (tp = tp->child_list) || NULL == tp->child_list) {
        config_pwarn("can't instatiate table since it doesn't appear to be "
                     "a proper table (no children)");
        return;
    }

    table_set = netsnmp_create_table_data_set(line);

    /*
     * check for augments indexes
     */
    if (NULL != tp->augments) {
        oid             name[MAX_OID_LEN];
        size_t          name_length = MAX_OID_LEN;
        struct tree    *tp2;
    
        if (!snmp_parse_oid(tp->augments, name, &name_length)) {
            config_pwarn("I can't parse the augment tabel name");
            snmp_log(LOG_WARNING, "  can't parse %s\n", tp->augments);
            return;
        }
        if(NULL == (tp2 = get_tree(name, name_length, get_tree_head()))) {
            config_pwarn("can't instatiate table since "
                         "I can't find mib information about augment table");
            snmp_log(LOG_WARNING, "  table %s not found in tree\n",
                     tp->augments);
            return;
        }
        _table_set_add_indexes(table_set, tp2);
    }

    _table_set_add_indexes(table_set, tp);
    
    /*
     * loop through children and add each column info 
     */
    for (tp = tp->child_list; tp; tp = tp->next_peer) {
        int             canwrite = 0;
        u_char          type;
        type = mib_to_asn_type(tp->type);
        if (type == (u_char) - 1) {
            config_pwarn("unknown column type");
            return;             /* xxx mem leak */
        }

        DEBUGMSGTL(("table_set_add_table",
                    "adding column %s(%d) of type %d (access %d)\n",
                    tp->label, tp->subid, type, tp->access));

        switch (tp->access) {
        case MIB_ACCESS_CREATE:
            table_set->allow_creation = 1;
        case MIB_ACCESS_READWRITE:
        case MIB_ACCESS_WRITEONLY:
            canwrite = 1;
        case MIB_ACCESS_READONLY:
            DEBUGMSGTL(("table_set_add_table",
                        "adding column %d of type %d\n", tp->subid, type));
            netsnmp_table_set_add_default_row(table_set, tp->subid, type,
                                              canwrite, NULL, 0);
            mincol = SNMP_MIN(mincol, tp->subid);
            maxcol = SNMP_MAX(maxcol, tp->subid);
            break;

        case MIB_ACCESS_NOACCESS:
        case MIB_ACCESS_NOTIFY:
            break;

        default:
            config_pwarn("unknown column access type");
            break;
        }
    }

    /*
     * register the table 
     */
    netsnmp_register_table_data_set(netsnmp_create_handler_registration
                                    (line, NULL, table_name,
                                     table_name_length,
                                     HANDLER_CAN_RWRITE), table_set, NULL);

    netsnmp_register_auto_data_table(table_set, NULL);
}
#endif /* NETSNMP_DISABLE_MIB_LOADING */

/** @internal */
void
netsnmp_config_parse_add_row(const char *token, char *line)
{
    char            buf[SNMP_MAXBUF_MEDIUM];
    char            tname[SNMP_MAXBUF_MEDIUM];
    size_t          buf_size;
    int             rc;

    data_set_tables *tables;
    netsnmp_variable_list *vb;  /* containing only types */
    netsnmp_table_row *row;
    netsnmp_table_data_set_storage *dr;

    line = copy_nword(line, tname, SNMP_MAXBUF_MEDIUM);

    tables = (data_set_tables *) netsnmp_get_list_data(auto_tables, tname);
    if (!tables) {
        config_pwarn("Unknown table trying to add a row");
        return;
    }

    /*
     * do the indexes first 
     */
    row = netsnmp_create_table_data_row();

    for (vb = tables->table_set->table->indexes_template; vb;
         vb = vb->next_variable) {
        if (!line) {
            config_pwarn("missing an index value");
            return;
        }

        DEBUGMSGTL(("table_set_add_row", "adding index of type %d\n",
                    vb->type));
        buf_size = SNMP_MAXBUF_MEDIUM;
        line = read_config_read_memory(vb->type, line, buf, &buf_size);
        netsnmp_table_row_add_index(row, vb->type, buf, buf_size);
    }

    /*
     * then do the data 
     */
    for (dr = tables->table_set->default_row; dr; dr = dr->next) {
        if (!line) {
            config_pwarn("missing a data value. "
                         "All columns must be specified.");
            snmp_log(LOG_WARNING,"  can't find value for column %d\n",
                     dr->column - 1);
            return;
        }

        buf_size = SNMP_MAXBUF_MEDIUM;
        line = read_config_read_memory(dr->type, line, buf, &buf_size);
        DEBUGMSGTL(("table_set_add_row",
                    "adding data at column %d of type %d\n", dr->column,
                    dr->type));
        netsnmp_set_row_column(row, dr->column, dr->type, buf, buf_size);
        if (dr->writable)
            netsnmp_mark_row_column_writable(row, dr->column, 1);       /* make writable */
    }
    rc = netsnmp_table_data_add_row(tables->table_set->table, row);
    if (SNMPERR_SUCCESS != rc) {
        config_pwarn("error adding table row");
    }
    if (NULL != line) {
        config_pwarn("extra data value. Too many columns specified.");
        snmp_log(LOG_WARNING,"  extra data '%s'\n", line);
    }
}


/* ==================================
 *
 * Data Set API: Row operations
 *
 * ================================== */

/** returns the first row in the table */
netsnmp_table_row *
netsnmp_table_data_set_get_first_row(netsnmp_table_data_set *table)
{
    return netsnmp_table_data_get_first_row(table->table);
}

/** returns the next row in the table */
netsnmp_table_row *
netsnmp_table_data_set_get_next_row(netsnmp_table_data_set *table,
                                    netsnmp_table_row      *row)
{
    return netsnmp_table_data_get_next_row(table->table, row);
}

int
netsnmp_table_set_num_rows(netsnmp_table_data_set *table)
{
    if (!table)
        return 0;
    return netsnmp_table_data_num_rows(table->table);
}

/* ==================================
 *
 * Data Set API: Column operations
 *
 * ================================== */

/** Finds a column within a given storage set, given the pointer to
   the start of the storage set list.
*/
netsnmp_table_data_set_storage *
netsnmp_table_data_set_find_column(netsnmp_table_data_set_storage *start,
                                   unsigned int column)
{
    while (start && start->column != column)
        start = start->next;
    return start;
}

/**
 * marks a given column in a row as writable or not.
 */
int
netsnmp_mark_row_column_writable(netsnmp_table_row *row, int column,
                                 int writable)
{
    netsnmp_table_data_set_storage *data;

    if (!row)
        return SNMPERR_GENERR;

    data = (netsnmp_table_data_set_storage *) row->data;
    data = netsnmp_table_data_set_find_column(data, column);

    if (!data) {
        /*
         * create it 
         */
        data = SNMP_MALLOC_TYPEDEF(netsnmp_table_data_set_storage);
        if (!data) {
            snmp_log(LOG_CRIT, "no memory in netsnmp_set_row_column");
            return SNMPERR_MALLOC;
        }
        data->column = column;
        data->writable = writable;
        data->next = row->data;
        row->data = data;
    } else {
        data->writable = writable;
    }
    return SNMPERR_SUCCESS;
}

/**
 * sets a given column in a row with data given a type, value, and
 * length.  Data is memdup'ed by the function.
 */
int
netsnmp_set_row_column(netsnmp_table_row *row, unsigned int column,
                       int type, const char *value, size_t value_len)
{
    netsnmp_table_data_set_storage *data;

    if (!row)
        return SNMPERR_GENERR;

    data = (netsnmp_table_data_set_storage *) row->data;
    data = netsnmp_table_data_set_find_column(data, column);

    if (!data) {
        /*
         * create it 
         */
        data = SNMP_MALLOC_TYPEDEF(netsnmp_table_data_set_storage);
        if (!data) {
            snmp_log(LOG_CRIT, "no memory in netsnmp_set_row_column");
            return SNMPERR_MALLOC;
        }

        data->column = column;
        data->type = type;
        data->next = row->data;
        row->data = data;
    }

    if (value) {
        if (data->type != type)
            return SNMPERR_GENERR;

        SNMP_FREE(data->data.voidp);
        if (value_len) {
            if (memdup(&data->data.string, value, (value_len)) !=
                SNMPERR_SUCCESS) {
                snmp_log(LOG_CRIT, "no memory in netsnmp_set_row_column");
                return SNMPERR_MALLOC;
            }
        } else {
            data->data.string = malloc(1);
        }
        data->data_len = value_len;
    }
    return SNMPERR_SUCCESS;
}

/* ==================================
 *
 * Data Set API: Index operations
 *
 * ================================== */

/** adds an index to the table.  Call this repeatly for each index. */
NETSNMP_INLINE void
netsnmp_table_dataset_add_index(netsnmp_table_data_set *table, u_char type)
{
    if (!table)
        return;
    netsnmp_table_data_add_index(table->table, type);
}

/** adds multiple indexes to a table_dataset helper object.
 *  To end the list, use a 0 after the list of ASN index types. */
void
#if HAVE_STDARG_H
netsnmp_table_set_add_indexes(netsnmp_table_data_set *tset,
                              ...)
#else
netsnmp_table_set_add_indexes(va_alist)
     va_dcl
#endif
{
    va_list         debugargs;
    int             type;

#if HAVE_STDARG_H
    va_start(debugargs, tset);
#else
    netsnmp_table_data_set *tset;

    va_start(debugargs);
    tset = va_arg(debugargs, netsnmp_table_data_set *);
#endif

    while ((type = va_arg(debugargs, int)) != 0) {
        netsnmp_table_dataset_add_index(tset, (u_char)type);
    }

    va_end(debugargs);
}

/** @} 
 */