1.1 --- a/src/cx/tree.h Sun Feb 18 13:16:38 2024 +0100
1.2 +++ b/src/cx/tree.h Sun Feb 18 13:38:42 2024 +0100
1.3 @@ -45,28 +45,6 @@
1.4 #endif
1.5
1.6 /**
1.7 - * When entering a node.
1.8 - *
1.9 - * When this is the first sibling, source is the parent, otherwise it is the previous child.
1.10 - */
1.11 -#define CX_TREE_ITERATOR_ENTER 0x1
1.12 -/**
1.13 - * When advancing to the next child.
1.14 - *
1.15 - * The visited node is the next child and the source is the previous child.
1.16 - * This pass is triggered after exiting the previous child and before entering the next child.
1.17 - */
1.18 -#define CX_TREE_ITERATOR_NEXT_CHILD 0x2
1.19 -/**
1.20 - * When exiting the node.
1.21 - *
1.22 - * The visited node is the node being exited and source is the previously entered node
1.23 - * (usually the last child of the exited node, unless it has no children, in which case it is the node itself).
1.24 - * When advancing to the next child in a list of siblings, the previous child is exited, first.
1.25 - */
1.26 -#define CX_TREE_ITERATOR_EXIT 0x4
1.27 -
1.28 -/**
1.29 * Tree iterator.
1.30 *
1.31 * This iterator is not position-aware in a strict sense, as it does not assume a particular order of elements in the
1.32 @@ -74,9 +52,8 @@
1.33 * Each node, regardless of the number of passes, is counted only once.
1.34 *
1.35 * @note Objects that are pointed to by an iterator are mutable through that iterator. However, if the
1.36 - * iterator is based on a collection and the underlying collection is mutated by other means than this iterator
1.37 - * (e.g. elements added or removed), the iterator becomes invalid (regardless of what cxIteratorValid() returns)
1.38 - * and MUST be re-obtained from the collection.
1.39 + * underlying data structure is mutated by other means than this iterator (e.g. elements added or removed),
1.40 + * the iterator becomes invalid (regardless of what cxIteratorValid() returns).
1.41 *
1.42 * @see CxIterator
1.43 */
1.44 @@ -86,20 +63,14 @@
1.45 */
1.46 struct cx_iterator_base_s base;
1.47 /**
1.48 - * The passes that are requested by this iterator.
1.49 - * A combination of the flags #CX_TREE_ITERATOR_ENTER, #CX_TREE_ITERATOR_NEXT_CHILD, #CX_TREE_ITERATOR_EXIT.
1.50 - *
1.51 - * Changing the value after beginning the iteration is unspecified.
1.52 + * Set to true, when the iterator shall visit a node again
1.53 + * when all it's children have been processed.
1.54 */
1.55 - uint8_t requested_passes;
1.56 + bool visit_on_exit;
1.57 /**
1.58 - * The current pass.
1.59 - *
1.60 - * @see CX_TREE_ITERATOR_ENTER
1.61 - * @see CX_TREE_ITERATOR_NEXT_CHILD
1.62 - * @see CX_TREE_ITERATOR_EXIT
1.63 + * True, if this iterator is currently leaving the node.
1.64 */
1.65 - uint8_t current_pass;
1.66 + bool exiting;
1.67 /**
1.68 * Offset in the node struct for the children linked list.
1.69 */
1.70 @@ -119,14 +90,6 @@
1.71 */
1.72 void *node;
1.73 /**
1.74 - * The node where we came from.
1.75 - *
1.76 - * - When entering the root node, this is \c NULL.
1.77 - * - When entering another node, this is the node's parent.
1.78 - * - When advancing to the next child, this is the previous child.
1.79 - */
1.80 - void *source;
1.81 - /**
1.82 * Internal stack.
1.83 * Will be automatically freed once the iterator becomes invalid.
1.84 *
1.85 @@ -138,10 +101,16 @@
1.86 * Internal capacity of the stack.
1.87 */
1.88 size_t stack_capacity;
1.89 - /**
1.90 - * Current depth.
1.91 - */
1.92 - size_t depth;
1.93 + union {
1.94 + /**
1.95 + * Internal stack size.
1.96 + */
1.97 + size_t stack_size;
1.98 + /**
1.99 + * The current depth in the tree.
1.100 + */
1.101 + size_t depth;
1.102 + };
1.103 } CxTreeIterator;
1.104
1.105 /**
1.106 @@ -261,17 +230,6 @@
1.107 /**
1.108 * Creates an iterator for a tree with the specified root node.
1.109 *
1.110 - * The \p passes argument is supposed to be a combination of the flags
1.111 - * #CX_TREE_ITERATOR_ENTER, #CX_TREE_ITERATOR_NEXT_CHILD, and #CX_TREE_ITERATOR_EXIT.
1.112 - * Alternatively, the integer 1 is equivalent to just specifying #CX_TREE_ITERATOR_ENTER
1.113 - * which will cause the iterator to pass every node only once (when entering the node).
1.114 - *
1.115 - * When #CX_TREE_ITERATOR_EXIT is set, the iterator will visit a parent node again,
1.116 - * when \em every of it's children has been visited (including the case when the node does not have any children).
1.117 - *
1.118 - * When #CX_TREE_ITERATOR_NEXT_CHILD is set, the iterator will visit a parent node again,
1.119 - * when advancing from one child to the next.
1.120 - *
1.121 * @note A tree iterator needs to maintain a stack of visited nodes, which is allocated using stdlib malloc().
1.122 * When the iterator becomes invalid, this memory is automatically released. However, if you wish to cancel the
1.123 * iteration before the iterator becomes invalid by itself, you MUST call cxTreeIteratorDispose() manually to release
1.124 @@ -280,7 +238,7 @@
1.125 * @remark At the moment, the returned iterator does not support cxIteratorFlagRemoval().
1.126 *
1.127 * @param root the root node
1.128 - * @param passes the passes this iterator shall perform
1.129 + * @param visit_on_exit set to true, when the iterator shall visit a node again after processing all children
1.130 * @param loc_children offset in the node struct for the children linked list
1.131 * @param loc_next offset in the node struct for the next pointer
1.132 * @return the new tree iterator
1.133 @@ -289,7 +247,7 @@
1.134 __attribute__((__nonnull__))
1.135 CxTreeIterator cx_tree_iterator(
1.136 void *root,
1.137 - int passes,
1.138 + bool visit_on_exit,
1.139 ptrdiff_t loc_children,
1.140 ptrdiff_t loc_next
1.141 );
