bool serialize_correctly(roaring_bitmap_t *r) {
uint32_t expectedsize = roaring_bitmap_portable_size_in_bytes(r);
char *serialized = malloc(expectedsize);
if (serialized == NULL) {
printf("failure to allocate memory!\n");
return false;
}
uint32_t serialize_len = roaring_bitmap_portable_serialize(r, serialized);
if (serialize_len != expectedsize) {
printf("Bad serialized size!\n");
free(serialized);
return false;
}
roaring_bitmap_t *r2 = roaring_bitmap_portable_deserialize(serialized);
free(serialized);
if (!roaring_bitmap_equals(r, r2)) {
printf("Won't recover original bitmap!\n");
roaring_bitmap_free(r2);
return false;
}
if (!roaring_bitmap_equals(r2, r)) {
printf("Won't recover original bitmap!\n");
roaring_bitmap_free(r2);
return false;
}
roaring_bitmap_free(r2);
return true;
}
void test_example(bool copy_on_write) {
// create a new empty bitmap
roaring_bitmap_t *r1 = roaring_bitmap_create();
r1->copy_on_write = copy_on_write;
assert_ptr_not_equal(r1, NULL);
// then we can add values
for (uint32_t i = 100; i < 1000; i++) {
roaring_bitmap_add(r1, i);
}
// check whether a value is contained
assert_true(roaring_bitmap_contains(r1, 500));
// compute how many bits there are:
uint32_t cardinality = roaring_bitmap_get_cardinality(r1);
printf("Cardinality = %d \n", cardinality);
assert_int_equal(900, cardinality);
// if your bitmaps have long runs, you can compress them by calling
// run_optimize
uint32_t size = roaring_bitmap_portable_size_in_bytes(r1);
roaring_bitmap_run_optimize(r1);
uint32_t compact_size = roaring_bitmap_portable_size_in_bytes(r1);
printf("size before run optimize %d bytes, and after %d bytes\n", size,
compact_size);
// create a new bitmap with varargs
roaring_bitmap_t *r2 = roaring_bitmap_of(5, 1, 2, 3, 5, 6);
assert_ptr_not_equal(r2, NULL);
roaring_bitmap_printf(r2);
printf("\n");
// we can also create a bitmap from a pointer to 32-bit integers
const uint32_t values[] = {2, 3, 4};
roaring_bitmap_t *r3 = roaring_bitmap_of_ptr(3, values);
r3->copy_on_write = copy_on_write;
// we can also go in reverse and go from arrays to bitmaps
uint64_t card1 = roaring_bitmap_get_cardinality(r1);
uint32_t *arr1 = new uint32_t[card1];
assert_ptr_not_equal(arr1, NULL);
roaring_bitmap_to_uint32_array(r1, arr1);
roaring_bitmap_t *r1f = roaring_bitmap_of_ptr(card1, arr1);
delete[] arr1;
assert_ptr_not_equal(r1f, NULL);
// bitmaps shall be equal
assert_true(roaring_bitmap_equals(r1, r1f));
roaring_bitmap_free(r1f);
// we can copy and compare bitmaps
roaring_bitmap_t *z = roaring_bitmap_copy(r3);
z->copy_on_write = copy_on_write;
assert_true(roaring_bitmap_equals(r3, z));
roaring_bitmap_free(z);
// we can compute union two-by-two
roaring_bitmap_t *r1_2_3 = roaring_bitmap_or(r1, r2);
r1_2_3->copy_on_write = copy_on_write;
roaring_bitmap_or_inplace(r1_2_3, r3);
// we can compute a big union
const roaring_bitmap_t *allmybitmaps[] = {r1, r2, r3};
roaring_bitmap_t *bigunion = roaring_bitmap_or_many(3, allmybitmaps);
assert_true(roaring_bitmap_equals(r1_2_3, bigunion));
roaring_bitmap_t *bigunionheap =
roaring_bitmap_or_many_heap(3, allmybitmaps);
assert_true(roaring_bitmap_equals(r1_2_3, bigunionheap));
roaring_bitmap_free(r1_2_3);
roaring_bitmap_free(bigunion);
roaring_bitmap_free(bigunionheap);
// we can compute intersection two-by-two
roaring_bitmap_t *i1_2 = roaring_bitmap_and(r1, r2);
roaring_bitmap_free(i1_2);
// we can write a bitmap to a pointer and recover it later
uint32_t expectedsize = roaring_bitmap_portable_size_in_bytes(r1);
char *serializedbytes = (char *)malloc(expectedsize);
roaring_bitmap_portable_serialize(r1, serializedbytes);
roaring_bitmap_t *t = roaring_bitmap_portable_deserialize(serializedbytes);
assert_true(expectedsize == roaring_bitmap_portable_size_in_bytes(t));
assert_true(roaring_bitmap_equals(r1, t));
roaring_bitmap_free(t);
free(serializedbytes);
// we can iterate over all values using custom functions
uint32_t counter = 0;
roaring_iterate(r1, roaring_iterator_sumall, &counter);
/**
* void roaring_iterator_sumall(uint32_t value, void *param) {
* *(uint32_t *) param += value;
* }
*
*/
roaring_bitmap_free(r1);
roaring_bitmap_free(r2);
roaring_bitmap_free(r3);
}