| /* | |
| * binaryheap.h | |
| * | |
| * A simple binary heap implementation | |
| * | |
| * Portions Copyright (c) 2012-2023, PostgreSQL Global Development Group | |
| * | |
| * src/include/lib/binaryheap.h | |
| */ | |
| /* | |
| * For a max-heap, the comparator must return <0 iff a < b, 0 iff a == b, | |
| * and >0 iff a > b. For a min-heap, the conditions are reversed. | |
| */ | |
| typedef int (*binaryheap_comparator) (Datum a, Datum b, void *arg); | |
| /* | |
| * binaryheap | |
| * | |
| * bh_size how many nodes are currently in "nodes" | |
| * bh_space how many nodes can be stored in "nodes" | |
| * bh_has_heap_property no unordered operations since last heap build | |
| * bh_compare comparison function to define the heap property | |
| * bh_arg user data for comparison function | |
| * bh_nodes variable-length array of "space" nodes | |
| */ | |
| typedef struct binaryheap | |
| { | |
| int bh_size; | |
| int bh_space; | |
| bool bh_has_heap_property; /* debugging cross-check */ | |
| binaryheap_comparator bh_compare; | |
| void *bh_arg; | |
| Datum bh_nodes[FLEXIBLE_ARRAY_MEMBER]; | |
| } binaryheap; | |
| extern binaryheap *binaryheap_allocate(int capacity, | |
| binaryheap_comparator compare, | |
| void *arg); | |
| extern void binaryheap_reset(binaryheap *heap); | |
| extern void binaryheap_free(binaryheap *heap); | |
| extern void binaryheap_add_unordered(binaryheap *heap, Datum d); | |
| extern void binaryheap_build(binaryheap *heap); | |
| extern void binaryheap_add(binaryheap *heap, Datum d); | |
| extern Datum binaryheap_first(binaryheap *heap); | |
| extern Datum binaryheap_remove_first(binaryheap *heap); | |
| extern void binaryheap_replace_first(binaryheap *heap, Datum d); | |