Inside Bitcoin

1// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file. See the AUTHORS file for names of contributors.
4
5#include "util/arena.h"
6
7#include "util/random.h"
8#include "util/testharness.h"
9
10namespace leveldb {
11
12class ArenaTest {};
13
14TEST(ArenaTest, Empty) { Arena arena; }
15
16TEST(ArenaTest, Simple) {
17  std::vector<std::pair<size_t, char*>> allocated;
18  Arena arena;
19  const int N = 100000;
20  size_t bytes = 0;
21  Random rnd(301);
22  for (int i = 0; i < N; i++) {
23    size_t s;
24    if (i % (N / 10) == 0) {
25      s = i;
26    } else {
27      s = rnd.OneIn(4000)
28              ? rnd.Uniform(6000)
29              : (rnd.OneIn(10) ? rnd.Uniform(100) : rnd.Uniform(20));
30    }
31    if (s == 0) {
32      // Our arena disallows size 0 allocations.
33      s = 1;
34    }
35    char* r;
36    if (rnd.OneIn(10)) {
37      r = arena.AllocateAligned(s);
38    } else {
39      r = arena.Allocate(s);
40    }
41
42    for (size_t b = 0; b < s; b++) {
43      // Fill the "i"th allocation with a known bit pattern
44      r[b] = i % 256;
45    }
46    bytes += s;
47    allocated.push_back(std::make_pair(s, r));
48    ASSERT_GE(arena.MemoryUsage(), bytes);
49    if (i > N / 10) {
50      ASSERT_LE(arena.MemoryUsage(), bytes * 1.10);
51    }
52  }
53  for (size_t i = 0; i < allocated.size(); i++) {
54    size_t num_bytes = allocated[i].first;
55    const char* p = allocated[i].second;
56    for (size_t b = 0; b < num_bytes; b++) {
57      // Check the "i"th allocation for the known bit pattern
58      ASSERT_EQ(int(p[b]) & 0xff, i % 256);
59    }
60  }
61}
62
63}  // namespace leveldb
64
65int main(int argc, char** argv) { return leveldb::test::RunAllTests(); }
66