n = tree->tbst_alloc->libavl_malloc (tree->tbst_alloc, sizeof *n); if (n == NULL) return NULL; tree->tbst_count++; n->tbst_data = item; n->tbst_tag[0] = n->tbst_tag[1] = TBST_THREAD; n->tbst_link[dir] = p->tbst_link[dir]; if (tree->tbst_root != NULL) { p->tbst_tag[dir] = TBST_CHILD; n->tbst_link[!dir] = p; } else n->tbst_link[1] = NULL; p->tbst_link[dir] = n;