xref: /aosp_15_r20/external/federated-compute/fcp/secagg/testing/fake_prng.h (revision 14675a029014e728ec732f129a32e299b2da0601)
1 /*
2  * Copyright 2018 Google LLC
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef FCP_SECAGG_TESTING_FAKE_PRNG_H_
18 #define FCP_SECAGG_TESTING_FAKE_PRNG_H_
19 
20 #include <cstdint>
21 
22 #include "fcp/secagg/shared/prng.h"
23 
24 namespace fcp {
25 namespace secagg {
26 
27 // Fake Implementation of SecurePrng that just returns constantly incrementing
28 // values.
29 
30 class FakePrng : public SecurePrng {
31  public:
32   // Returns 1, 2, 3, etc.
33   FakePrng() = default;
34 
35   // Returns the selected value first, and increments by 1 each time from there.
FakePrng(uint64_t value)36   explicit FakePrng(uint64_t value) : value_(value - 1) {}
37 
Rand8()38   uint8_t Rand8() override { return static_cast<uint8_t>(++value_); }
Rand64()39   uint64_t Rand64() override { return ++value_; }
40 
41  private:
42   uint64_t value_ = 0;
43 };
44 
45 }  // namespace secagg
46 }  // namespace fcp
47 
48 #endif  // FCP_SECAGG_TESTING_FAKE_PRNG_H_
49