90 lines
2.7 KiB
C++
90 lines
2.7 KiB
C++
|
// Copyright 2021 The Tint Authors.
|
||
|
|
//
|
||
|
|
// Licensed 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 "fuzzers/random_generator.h"
|
||
|
|
|
||
|
|
#include <algorithm>
|
||
|
|
#include <cassert>
|
||
|
|
#include <vector>
|
||
|
|
|
||
|
|
namespace tint {
|
||
|
|
namespace fuzzers {
|
||
|
|
|
||
|
|
namespace {
|
||
|
|
|
||
|
|
/// Generate integer from uniform distribution
|
||
|
|
/// @tparam I - integer type
|
||
|
|
/// @param engine - random number engine to use
|
||
|
|
/// @param lower - Lower bound of integer generated
|
||
|
|
/// @param upper - Upper bound of integer generated
|
||
|
|
/// @returns i, where lower <= i < upper
|
||
|
|
template <typename I>
|
||
|
|
I RandomUInt(std::mt19937* engine, I lower, I upper) {
|
||
|
|
assert(lower < upper && "|lower| must be stictly less than |upper|");
|
||
|
|
|
||
|
|
return std::uniform_int_distribution<I>(lower, upper - 1)(*engine);
|
||
|
|
}
|
||
|
|
|
||
|
|
} // namespace
|
||
|
|
|
||
|
|
RandomGenerator::RandomGenerator(uint32_t seed) : engine_(seed) {}
|
||
|
|
|
||
|
|
uint32_t RandomGenerator::GetUInt32(uint32_t lower, uint32_t upper) {
|
||
|
|
return RandomUInt(&engine_, lower, upper);
|
||
|
|
}
|
||
|
|
|
||
|
|
uint32_t RandomGenerator::GetUInt32(uint32_t bound) {
|
||
|
|
assert(bound > 0 && "|bound| must be greater than 0");
|
||
|
|
return RandomUInt(&engine_, 0u, bound);
|
||
|
|
}
|
||
|
|
|
||
|
|
uint64_t RandomGenerator::GetUInt64(uint64_t lower, uint64_t upper) {
|
||
|
|
return RandomUInt(&engine_, lower, upper);
|
||
|
|
}
|
||
|
|
|
||
|
|
uint64_t RandomGenerator::GetUInt64(uint64_t bound) {
|
||
|
|
assert(bound > 0 && "|bound| must be greater than 0");
|
||
|
|
return RandomUInt(&engine_, static_cast<uint64_t>(0), bound);
|
||
|
|
}
|
||
|
|
|
||
|
|
uint8_t RandomGenerator::GetByte() {
|
||
|
|
return std::independent_bits_engine<std::mt19937, 8, uint8_t>(engine_)();
|
||
|
|
}
|
||
|
|
|
||
|
|
uint32_t RandomGenerator::Get4Bytes() {
|
||
|
|
return std::independent_bits_engine<std::mt19937, 32, uint32_t>(engine_)();
|
||
|
|
}
|
||
|
|
|
||
|
|
std::vector<uint8_t> RandomGenerator::GetNBytes(size_t n) {
|
||
|
|
std::vector<uint8_t> result(n);
|
||
|
|
std::generate(
|
||
|
|
std::begin(result), std::end(result),
|
||
|
|
std::independent_bits_engine<std::mt19937, 8, uint8_t>(engine_));
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
bool RandomGenerator::GetBool() {
|
||
|
|
return RandomUInt(&engine_, 0u, 2u);
|
||
|
|
}
|
||
|
|
|
||
|
|
bool RandomGenerator::GetWeightedBool(uint32_t percentage) {
|
||
|
|
static const uint32_t kMaxPercentage = 100;
|
||
|
|
assert(percentage <= kMaxPercentage &&
|
||
|
|
"|percentage| needs to be within [0, 100]");
|
||
|
|
return RandomUInt(&engine_, 0u, kMaxPercentage) < percentage;
|
||
|
|
}
|
||
|
|
|
||
|
|
} // namespace fuzzers
|
||
|
|
} // namespace tint
|