Inside Bitcoin

1/**********************************************************************
2 * Copyright (c) 2018 Pieter Wuille, Greg Maxwell, Gleb Naumenko      *
3 * Distributed under the MIT software license, see the accompanying   *
4 * file LICENSE or http://www.opensource.org/licenses/mit-license.php.*
5 **********************************************************************/
6
7#include <stdio.h>
8#include <assert.h>
9#include "../include/minisketch.h"
10
11int main(void) {
12
13  minisketch *sketch_a = minisketch_create(12, 0, 4);
14
15  for (int i = 3000; i < 3010; ++i) {
16    minisketch_add_uint64(sketch_a, i);
17  }
18
19  size_t sersize = minisketch_serialized_size(sketch_a);
20  assert(sersize == 12 * 4 / 8); // 4 12-bit values is 6 bytes.
21  unsigned char *buffer_a = malloc(sersize);
22  minisketch_serialize(sketch_a, buffer_a);
23  minisketch_destroy(sketch_a);
24
25  minisketch *sketch_b = minisketch_create(12, 0, 4); // Bob's own sketch
26  for (int i = 3002; i < 3012; ++i) {
27    minisketch_add_uint64(sketch_b, i);
28  }
29
30  sketch_a = minisketch_create(12, 0, 4);     // Alice's sketch
31  minisketch_deserialize(sketch_a, buffer_a); // Load Alice's sketch
32  free(buffer_a);
33
34  // Merge the elements from sketch_a into sketch_b. The result is a sketch_b
35  // which contains all elements that occurred in Alice's or Bob's sets, but not
36  // in both.
37  minisketch_merge(sketch_b, sketch_a);
38
39  uint64_t differences[4];
40  ssize_t num_differences = minisketch_decode(sketch_b, 4, differences);
41  minisketch_destroy(sketch_a);
42  minisketch_destroy(sketch_b);
43  if (num_differences < 0) {
44    printf("More than 4 differences!\n");
45  } else {
46    ssize_t i;
47    for (i = 0; i < num_differences; ++i) {
48      printf("%u is in only one of the two sets\n", (unsigned)differences[i]);
49    }
50  }
51}
52