Function to free whole datatree

[lukasmacko]

I would like to suggest including a function that frees whole data tree including siblings. It doesn't make difference if there is only one node at root level, however if there are multiple nodes it would be handy. Currently, you can read data tree by one function call but you have to use loop to free it.

Example:

module example-module {
   namespace "urn:ietf:params:xml:ns:yang:example";
   prefix ie; 

   organization "organization";
   description  "example yang module";
   contact      "contact@example.com";

   container container {
      config true;
      list list {
         leaf leaf {
            type string;
         }
         leaf key1 {
            type string;
         }
         key "key1";
      }   
   }   
   leaf-list number{
      type uint16;
   }   
}

FILE *data = fopen("example-module.data","r"); 

struct lyd_node *data_tree = lyd_parse_fd(ctx, fileno(data), LYD_XML, 0); 
fclose(data); 
lyd_free(data_tree); /*This causes MEMLEAK if data contains container and leaflist*/

My suggestion:

/**
 * Free the subtree and its siblings.
 * @param [in] root
 */
void lyd_free_datatree(struct lyd_node *root){
    struct lyd_node *next = NULL;
    while(NULL != root){
        next = root->next;
        lyd_free(root);
        root = next;
    }
}

(The function name could be also lyd_free_with_siblings.)

What do you think? Or is there something I've overlooked?

[rkrejci]

My first thinking was that using simple loop or our LY_TREE_FOR/LYTREE_FOR_SAFE macros is not a big deal for callers. But now I see that the function makes sense since there is possible some optimization in case the provided node is not the "first" sibling. The function was named lyd_free_withsiblings() and it is available from 0.5.3.

[lukasmacko]

ok, thanks!