1// (C) Copyright Andy Tompkins 2010. Permission to copy, use, modify, sell and
2// distribute this software is granted provided this copyright notice appears
3// in all copies. This software is provided "as is" without express or implied
4// warranty, and with no claim as to its suitability for any purpose.
5
6// Distributed under the Boost Software License, Version 1.0. (See
7// accompanying file LICENSE_1_0.txt or copy at
8// https://www.boost.org/LICENSE_1_0.txt)
9
10// libs/uuid/test/test_random_generator.cpp -------------------------------//
11
12#include <boost/core/ignore_unused.hpp>
13#include <boost/detail/lightweight_test.hpp>
14#include <boost/predef/library/c/cloudabi.h>
15#include <boost/random.hpp>
16#include <boost/uuid/entropy_error.hpp>
17#include <boost/uuid/random_generator.hpp>
18#include <boost/uuid/uuid_io.hpp>
19#include <boost/uuid/uuid.hpp>
20#include <boost/move/utility_core.hpp>
21
22template <typename RandomUuidGenerator>
23void check_random_generator(RandomUuidGenerator& uuid_gen)
24{
25 boost::uuids::uuid u1 = uuid_gen();
26 boost::uuids::uuid u2 = uuid_gen();
27
28 BOOST_TEST_NE(u1, u2);
29
30 // check variant
31 BOOST_TEST_EQ(u1.variant(), boost::uuids::uuid::variant_rfc_4122);
32
33 // version
34 BOOST_TEST_EQ(u1.version(), boost::uuids::uuid::version_random_number_based);
35}
36
37// This is the example block from the documentation - ensure it works!
38void test_examples()
39{
40 // Depending on the platform there may be a setup cost in
41 // initializing the generator so plan to reuse it if you can.
42 boost::uuids::random_generator gen;
43 boost::uuids::uuid id = gen();
44 boost::uuids::uuid id2 = gen();
45#if !BOOST_LIB_C_CLOUDABI
46 std::cout << id << std::endl;
47 std::cout << id2 << std::endl;
48#endif
49 BOOST_TEST_NE(id, id2);
50 boost::ignore_unused(id);
51 boost::ignore_unused(id2);
52
53 // You can still use a PseudoRandomNumberGenerator to create
54 // UUIDs, however this is not the preferred mechanism. For
55 // large numbers of UUIDs this may be more CPU efficient but
56 // it comes with all the perils of a PRNG. The test code
57 // in test_bench_random identifies the transition point for
58 // a given system.
59 boost::uuids::random_generator_mt19937 bulkgen;
60 for (size_t i = 0; i < 1000; ++i)
61 {
62 boost::uuids::uuid u = bulkgen();
63 // do something with u
64 boost::ignore_unused(u);
65 }
66}
67
68int main(int, char*[])
69{
70 using namespace boost::uuids;
71
72 // default random number generator
73 {
74 random_generator uuid_gen1;
75 check_random_generator(uuid_gen&: uuid_gen1);
76#if !BOOST_LIB_C_CLOUDABI
77 // dump 10 of them to cout for observation
78 for (size_t i = 0; i < 10; ++i)
79 {
80 std::cout << uuid_gen1() << std::endl;
81 }
82#endif
83 }
84
85 // specific random number generator
86 {
87 basic_random_generator<boost::rand48> uuid_gen2;
88 check_random_generator(uuid_gen&: uuid_gen2);
89 }
90
91 // pass by reference
92 {
93 boost::ecuyer1988 ecuyer1988_gen;
94 basic_random_generator<boost::ecuyer1988> uuid_gen3(ecuyer1988_gen);
95 check_random_generator(uuid_gen&: uuid_gen3);
96 }
97
98 // pass by pointer
99 {
100 boost::lagged_fibonacci607 lagged_fibonacci607_gen;
101 basic_random_generator<boost::lagged_fibonacci607> uuid_gen4(&lagged_fibonacci607_gen);
102 check_random_generator(uuid_gen&: uuid_gen4);
103 }
104
105 // check move construction
106 {
107 random_generator uuid_gen1;
108 random_generator uuid_gen2(boost::move(t&: uuid_gen1));
109 boost::ignore_unused(uuid_gen2);
110 }
111 {
112 basic_random_generator<boost::rand48> uuid_gen1;
113 basic_random_generator<boost::rand48> uuid_gen2(boost::move(t&: uuid_gen1));
114 boost::ignore_unused(uuid_gen2);
115 }
116
117 // check move assignment
118 {
119 random_generator uuid_gen1, uuid_gen2;
120 uuid_gen2 = boost::move(t&: uuid_gen1);
121 boost::ignore_unused(uuid_gen2);
122 }
123 {
124 basic_random_generator<boost::rand48> uuid_gen1, uuid_gen2;
125 uuid_gen2 = boost::move(t&: uuid_gen1);
126 boost::ignore_unused(uuid_gen2);
127 }
128
129 // there was a bug in basic_random_generator where it did not
130 // produce very random numbers. This checks for that bug.
131 {
132 random_generator_mt19937 bulkgen;
133 uuid u = bulkgen();
134 if ((u.data[4] == u.data[12]) &&
135 (u.data[5] == u.data[9] && u.data[5] == u.data[13]) &&
136 (u.data[7] == u.data[11] && u.data[7] == u.data[15]) &&
137 (u.data[10] == u.data[14]))
138 {
139 BOOST_ERROR("basic_random_generator is not producing random uuids");
140 }
141
142 // pseudo
143 check_random_generator(uuid_gen&: bulkgen);
144 }
145
146 // make sure default construction seeding is happening for PRNGs
147 {
148 random_generator_mt19937 gen1;
149 random_generator_mt19937 gen2;
150 BOOST_TEST_NE(gen1(), gen2());
151 }
152
153 // The example code snippet in the documentation
154 test_examples();
155
156 return boost::report_errors();
157}
158

source code of boost/libs/uuid/test/test_random_generator.cpp