1.1 --- a/src/tree.c Mon Feb 19 22:12:13 2024 +0100
1.2 +++ b/src/tree.c Wed Feb 21 18:32:38 2024 +0100
1.3 @@ -182,40 +182,58 @@
1.4 off_t const loc_children = iter->loc_children;
1.5
1.6 // TODO: support mutating iterator
1.7 - // TODO: support visit_on_exit
1.8
1.9 - void *children = tree_children(iter->node);
1.10 + void *children;
1.11 +
1.12 + // check if we are currently exiting or entering nodes
1.13 + if (iter->exiting) {
1.14 + children = NULL;
1.15 + } else {
1.16 + children = tree_children(iter->node);
1.17 + }
1.18 +
1.19 if (children == NULL) {
1.20 // search for the next node
1.21 - void *current = iter->node;
1.22 - do {
1.23 - // check if there is a sibling
1.24 - void *next = tree_next(current);
1.25 - if (next == NULL) {
1.26 - // no sibling, check again for parent node
1.27 - --iter->depth;
1.28 - if (iter->depth == 0) {
1.29 + void *next;
1.30 + cx_tree_iter_search_next:
1.31 + // check if there is a sibling
1.32 + next = tree_next(iter->node);
1.33 + if (next == NULL) {
1.34 + // no sibling, we are done with this node and exit
1.35 + if (iter->visit_on_exit && !iter->exiting) {
1.36 + // iter is supposed to visit the node again
1.37 + iter->exiting = true;
1.38 + } else {
1.39 + iter->exiting = false;
1.40 + if (iter->depth == 1) {
1.41 // there is no parent - we have iterated the entire tree
1.42 // invalidate the iterator and free the node stack
1.43 iter->node = NULL;
1.44 - current = NULL;
1.45 - iter->stack_capacity = 0;
1.46 + iter->stack_capacity = iter->depth = 0;
1.47 free(iter->stack);
1.48 iter->stack = NULL;
1.49 } else {
1.50 // the parent node can be obtained from the top of stack
1.51 // this way we can avoid the loc_parent in the iterator
1.52 - current = iter->stack[iter->depth - 1];
1.53 + iter->depth--;
1.54 + iter->node = iter->stack[iter->depth - 1];
1.55 + // retry with the parent node to find a sibling
1.56 + goto cx_tree_iter_search_next;
1.57 }
1.58 + }
1.59 + } else {
1.60 + if (iter->visit_on_exit && !iter->exiting) {
1.61 + // iter is supposed to visit the node again
1.62 + iter->exiting = true;
1.63 } else {
1.64 - // move to the sibling and break the loop
1.65 - current = NULL;
1.66 + iter->exiting = false;
1.67 + // move to the sibling
1.68 iter->counter++;
1.69 iter->node = next;
1.70 // new top of stack is the sibling
1.71 iter->stack[iter->depth - 1] = next;
1.72 }
1.73 - } while (current != NULL);
1.74 + }
1.75 } else {
1.76 // node has children, push the first child onto the stack and enter it
1.77 cx_array_simple_add(iter->stack, children);
