7#ifndef _PICO_UTIL_PHEAP_H
8#define _PICO_UTIL_PHEAP_H
17#ifndef PARAM_ASSERTIONS_ENABLED_PHEAP
18#define PARAM_ASSERTIONS_ENABLED_PHEAP 0
39#ifndef PICO_PHEAP_MAX_ENTRIES
40#define PICO_PHEAP_MAX_ENTRIES 255
44#if PICO_PHEAP_MAX_ENTRIES < 256
45typedef uint8_t pheap_node_id_t;
46#elif PICO_PHEAP_MAX_ENTRIES < 65535
47typedef uint16_t pheap_node_id_t;
49#error invalid PICO_PHEAP_MAX_ENTRIES
53 pheap_node_id_t child, sibling, parent;
61typedef bool (*
pheap_comparator)(
void *user_data, pheap_node_id_t a, pheap_node_id_t b);
67 pheap_node_id_t max_nodes;
68 pheap_node_id_t root_id;
70 pheap_node_id_t free_head_id;
71 pheap_node_id_t free_tail_id;
105 assert(
id && id <= heap->max_nodes);
106 return heap->nodes +
id - 1;
110static void ph_add_child_node(
pheap_t *heap, pheap_node_id_t parent_id, pheap_node_id_t child_id) {
114 assert(parent_id != child_id);
116 c->parent = parent_id;
120 c->sibling = n->child;
126static pheap_node_id_t ph_merge_nodes(
pheap_t *heap, pheap_node_id_t a, pheap_node_id_t b) {
129 if (heap->comparator(heap->user_data, a, b)) {
130 ph_add_child_node(heap, a, b);
133 ph_add_child_node(heap, b, a);
145 if (!heap->free_head_id)
return 0;
146 pheap_node_id_t
id = heap->free_head_id;
148 heap->free_head_id = hn->sibling;
149 if (!heap->free_head_id) heap->free_tail_id = 0;
150 hn->child = hn->sibling = hn->parent = 0;
168 hn->child = hn->sibling = hn->parent = 0;
169 heap->root_id = ph_merge_nodes(heap, heap->root_id,
id);
170 return heap->root_id;
181 return heap->root_id;
236 return id == heap->root_id || ph_get_node(heap,
id)->parent;
248 if (heap->free_tail_id) {
249 ph_get_node(heap, heap->free_tail_id)->sibling = id;
251 heap->free_tail_id = id;
261void ph_dump(
pheap_t *heap,
void (*dump_key)(pheap_node_id_t
id,
void *user_data),
void *user_data);
278#define PHEAP_DEFINE_STATIC(name, _max_nodes) \
279 static_assert(_max_nodes && _max_nodes < (1u << (8 * sizeof(pheap_node_id_t))), ""); \
280 static pheap_node_t name ## _nodes[_max_nodes]; \
281 static pheap_t name = { \
282 .nodes = name ## _nodes, \
283 .max_nodes = _max_nodes \
bool(* pheap_comparator)(void *user_data, pheap_node_id_t a, pheap_node_id_t b)
A user comparator function for nodes in a pairing heap.
Definition: pheap.h:61
void ph_destroy(pheap_t *heap)
De-allocates a pairing heap.
Definition: pheap.c:37
static void ph_free_node(pheap_t *heap, pheap_node_id_t id)
Free a node that is not currently in the heap, but has been allocated.
Definition: pheap.h:246
void ph_clear(pheap_t *heap)
Removes all nodes from the pairing heap.
Definition: pheap.c:27
void ph_post_alloc_init(pheap_t *heap, uint max_nodes, pheap_comparator comparator, void *user_data)
Initialize a statically allocated heap (ph_create() using the C heap).
Definition: pheap.c:19
static bool ph_contains_node(pheap_t *heap, pheap_node_id_t id)
Determine if the heap contains a given node.
Definition: pheap.h:235
bool ph_remove_and_free_node(pheap_t *heap, pheap_node_id_t id)
Remove and free an arbitrary node from the pairing heap.
Definition: pheap.c:78
pheap_node_id_t ph_remove_head(pheap_t *heap, bool free)
Remove the head node from the pairing heap.
Definition: pheap.c:72
static pheap_node_id_t ph_peek_head(pheap_t *heap)
Returns the head node in the heap, i.e.
Definition: pheap.h:180
void ph_dump(pheap_t *heap, void(*dump_key)(pheap_node_id_t id, void *user_data), void *user_data)
Print a representation of the heap for debugging.
static pheap_node_id_t ph_insert_node(pheap_t *heap, pheap_node_id_t id)
Inserts a node into the heap.
Definition: pheap.h:165
pheap_t * ph_create(uint max_nodes, pheap_comparator comparator, void *user_data)
Create a pairing heap, which effectively maintains an efficient sorted ordering of nodes.
Definition: pheap.c:11
static pheap_node_id_t ph_remove_and_free_head(pheap_t *heap)
Remove the head node from the pairing heap.
Definition: pheap.h:213
static pheap_node_id_t ph_new_node(pheap_t *heap)
Allocate a new node from the unused space in the heap.
Definition: pheap.h:144