1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
|
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
//
#include "util/random.h"
#include <climits>
#include <cstdint>
#include <cstring>
#include <thread>
#include <utility>
#include "port/likely.h"
#include "util/aligned_storage.h"
#include "util/thread_local.h"
#define STORAGE_DECL static thread_local
namespace ROCKSDB_NAMESPACE {
Random* Random::GetTLSInstance() {
STORAGE_DECL Random* tls_instance;
STORAGE_DECL aligned_storage<Random>::type tls_instance_bytes;
auto rv = tls_instance;
if (UNLIKELY(rv == nullptr)) {
size_t seed = std::hash<std::thread::id>()(std::this_thread::get_id());
rv = new (&tls_instance_bytes) Random((uint32_t)seed);
tls_instance = rv;
}
return rv;
}
std::string Random::HumanReadableString(int len) {
std::string ret;
ret.resize(len);
for (int i = 0; i < len; ++i) {
ret[i] = static_cast<char>('a' + Uniform(26));
}
return ret;
}
std::string Random::RandomString(int len) {
std::string ret;
ret.resize(len);
for (int i = 0; i < len; i++) {
ret[i] = static_cast<char>(' ' + Uniform(95)); // ' ' .. '~'
}
return ret;
}
std::string Random::RandomBinaryString(int len) {
std::string ret;
ret.resize(len);
for (int i = 0; i < len; i++) {
ret[i] = static_cast<char>(Uniform(CHAR_MAX));
}
return ret;
}
} // namespace ROCKSDB_NAMESPACE
|
