| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you under the Apache License, Version 2.0 (the |
| // "License"); you may not use this file except in compliance |
| // with the License. You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, |
| // software distributed under the License is distributed on an |
| // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| // KIND, either express or implied. See the License for the |
| // specific language governing permissions and limitations |
| // under the License. |
| |
| #include "kudu/util/random_util.h" |
| |
| #include <algorithm> |
| #include <cmath> |
| #include <cstring> |
| |
| #include "kudu/util/random.h" |
| #include "kudu/util/test_util.h" |
| |
| namespace kudu { |
| |
| class RandomUtilTest : public KuduTest { |
| protected: |
| RandomUtilTest() : rng_(SeedRandom()) {} |
| |
| Random rng_; |
| |
| static const int kLenMax = 100; |
| static const int kNumTrials = 100; |
| }; |
| |
| namespace { |
| |
| // Checks string defined at start is set to \0 everywhere but [from, to) |
| void CheckEmpty(char* start, int from, int to, int stop) { |
| DCHECK_LE(0, from); |
| DCHECK_LE(from, to); |
| DCHECK_LE(to, stop); |
| for (int j = 0; (j == from ? j = to : j) < stop; ++j) { |
| CHECK_EQ(start[j], '\0') << "Index " << j << " not null after defining" |
| << "indices [" << from << "," << to << ") of " |
| << "a nulled string [0," << stop << ")."; |
| } |
| } |
| |
| } // anonymous namespace |
| |
| // Makes sure that RandomString only writes the specified amount |
| TEST_F(RandomUtilTest, TestRandomString) { |
| char start[kLenMax]; |
| |
| for (int i = 0; i < kNumTrials; ++i) { |
| memset(start, '\0', kLenMax); |
| int to = rng_.Uniform(kLenMax + 1); |
| int from = rng_.Uniform(to + 1); |
| RandomString(start + from, to - from, &rng_); |
| CheckEmpty(start, from, to, kLenMax); |
| } |
| |
| // Corner case |
| memset(start, '\0', kLenMax); |
| RandomString(start, 0, &rng_); |
| CheckEmpty(start, 0, 0, kLenMax); |
| } |
| |
| } // namespace kudu |