* Data captures the current state and will not be updated.
* Caller must deallocate data when done.
*/
-meshlink_edge_t **meshlink_get_all_edges_state(meshlink_handle_t *mesh, size_t *nmemb) {
- if(!mesh || !nmemb) {
+meshlink_edge_t **meshlink_get_all_edges_state(meshlink_handle_t *mesh, meshlink_edge_t **edges, size_t *nmemb) {
+ if(!mesh || !nmemb || (*nmemb && !edges)) {
meshlink_errno = MESHLINK_EINVAL;
return NULL;
}
meshlink_edge_t **result = NULL;
meshlink_edge_t *copy = NULL;
+ int result_size = 0;
- // mesh->edges->count is the max size
- *nmemb = mesh->edges->count;
+ result_size = mesh->edges->count;
- result = xzalloc(*nmemb * sizeof (meshlink_edge_t*));
+ // if result is smaller than edges, we have to dealloc all the excess meshlink_edge_t
+ if(result_size > *nmemb) {
+ result = realloc(edges, result_size * sizeof (meshlink_edge_t*));
+ } else {
+ result = edges;
+ }
if(result) {
meshlink_edge_t **p = result;
+ int n = 0;
for splay_each(edge_t, e, mesh->edges) {
// skip edges that do not represent a two-directional connection
if((!e->reverse) || (e->reverse->to != e->from)) {
- *nmemb--;
+ result_size--;
continue;
}
- // copy the edge so it can't be mutated
- copy = xzalloc(sizeof *copy);
+ n++;
+ // the first *nmemb members of result can be re-used
+ if(n > *nmemb) {
+ copy = xzalloc(sizeof *copy);
+ }
+ else {
+ copy = *p;
+ }
copy->from = (meshlink_node_t*)e->from;
copy->to = (meshlink_node_t*)e->to;
#ifdef HAVE_STRUCT_SOCKADDR_STORAGE
*p++ = copy;
}
// shrink result to the actual amount of memory used
- result = realloc(result, *nmemb * sizeof (meshlink_edge_t*));
+ for(int i = *nmemb; i > result_size; i--) {
+ free(result[i - 1]);
+ }
+ result = realloc(result, result_size * sizeof (meshlink_edge_t*));
+ *nmemb = result_size;
} else {
*nmemb = 0;
+ free(result);
meshlink_errno = MESHLINK_ENOMEM;
}