1 // Copyright 2018 The Abseil Authors.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #include "absl/container/internal/hash_generator_testing.h"
16
17 #include <deque>
18
19 #include "absl/base/no_destructor.h"
20
21 namespace absl {
22 ABSL_NAMESPACE_BEGIN
23 namespace container_internal {
24 namespace hash_internal {
25 namespace {
26
27 class RandomDeviceSeedSeq {
28 public:
29 using result_type = typename std::random_device::result_type;
30
31 template <class Iterator>
generate(Iterator start,Iterator end)32 void generate(Iterator start, Iterator end) {
33 while (start != end) {
34 *start = gen_();
35 ++start;
36 }
37 }
38
39 private:
40 std::random_device gen_;
41 };
42
43 } // namespace
44
GetSharedRng()45 std::mt19937_64* GetSharedRng() {
46 static absl::NoDestructor<std::mt19937_64> rng([] {
47 RandomDeviceSeedSeq seed_seq;
48 return std::mt19937_64(seed_seq);
49 }());
50 return rng.get();
51 }
52
operator ()() const53 std::string Generator<std::string>::operator()() const {
54 // NOLINTNEXTLINE(runtime/int)
55 std::uniform_int_distribution<short> chars(0x20, 0x7E);
56 std::string res;
57 res.resize(32);
58 std::generate(res.begin(), res.end(),
59 [&]() { return chars(*GetSharedRng()); });
60 return res;
61 }
62
operator ()() const63 absl::string_view Generator<absl::string_view>::operator()() const {
64 static absl::NoDestructor<std::deque<std::string>> arena;
65 // NOLINTNEXTLINE(runtime/int)
66 std::uniform_int_distribution<short> chars(0x20, 0x7E);
67 arena->emplace_back();
68 auto& res = arena->back();
69 res.resize(32);
70 std::generate(res.begin(), res.end(),
71 [&]() { return chars(*GetSharedRng()); });
72 return res;
73 }
74
75 } // namespace hash_internal
76 } // namespace container_internal
77 ABSL_NAMESPACE_END
78 } // namespace absl
79