Directory callback example

The following example fragment defines a directory callback. This callback:

• Confirms that the directory object pointer is valid.

• Adds the directory object to the application’s list of servers by calling the sil_add_object example routine. When the mainline code calls ct_ds_lookup, it passes the address of an initialized SERVER_INFO_LIST as the ct_ds_lookup userdata parameter. The callback receives the same address as its own userdata parameter.

• If the list of servers is full, the callback returns CS_SUCCEED to truncate the search results. Otherwise, the callback returns CS_CONTINUE.

 /*

 ** directory_cb() -- Directory callback to install in Client-Library.

 **   When we call ct_ds_lookup(), Client-Library calls this function

 **   once for each object that is found in the search.

 **

 **   This particular callback collects the objects in

 **   the SERVER_INFO_LIST that is received as userdata.

 **

 ** Parameters

 **   conn -- The connection handle passed to ct_ds_lookup() to

 **      begin the search.

 **   reqid -- The request id for the operation (assigned by Client-Library).

 **   status -- CS_SUCCEED when search succeeded (ds_object is valid).

 **      CS_FAIL if the search failed (ds_object is not valid).

 **   numentries -- The count of objects to be returned for the

 **      search. Includes the current object. Can be 0 if search

 **      failed.

 **   ds_object -- Pointer to a CS_DS_OBJECT structure. Will

 **      be NULL if the search failed.

 **   userdata -- The address of user-allocated data that was

 **      passed to ct_ds_lookup().

 **

 **      This particular callback requires userdata to be the

 **      address of a valid, initialized SERVER_INFO_LIST pointer.

 **      (SERVER_INFO_LIST is an application data structure defined

 **      by this sample).

 **

 ** Returns

 **   CS_CONTINUE unless the SERVER_INFO_LIST pointed at by userdata fills

 **     up, then CS_SUCCEED to truncate the search results.

 */

 S_RETCODE          CS_PUBLIC

 directory_cb(conn, reqid, status, numentries, ds_object, userdata)

 CS_CONNECTION      *conn;

 CS_INT              reqid;

 CS_RETCODE          status;

 CS_INT              numentries;

 CS_DS_OBJECT       *ds_object;

 CS_VOID            *userdata;

 {

     CS_RETCODE          ret;

     SERVER_INFO_LIST   *server_list;

     if (status != CS_SUCCEED || numentries <= 0)

     {

         return CS_SUCCEED;

     }

     /*

     ** Append the object to the list of servers.

     */

     server_list = *((SERVER_INFO_LIST **)userdata);

     ret = sil_add_object(server_list, ds_object);

     if (ret != CS_SUCCEED)

     {

         /*

         ** Return CS_SUCCEED to discard the rest of the objects that were

         ** found in the search.

         */

         ex_error(

            "directory_cb: Too many servers! Truncating search results.");

         return CS_SUCCEED;

     }

     /*
     ** Return CS_CONTINUE so Client-Library will call us again if more

     ** entries are found.

     */

     return CS_CONTINUE;

 } /* directory_cb() */