summaryrefslogtreecommitdiff
path: root/absl/random/internal/sequence_urbg.h
diff options
context:
space:
mode:
Diffstat (limited to 'absl/random/internal/sequence_urbg.h')
-rw-r--r--absl/random/internal/sequence_urbg.h56
1 files changed, 56 insertions, 0 deletions
diff --git a/absl/random/internal/sequence_urbg.h b/absl/random/internal/sequence_urbg.h
new file mode 100644
index 00000000..9a9b5773
--- /dev/null
+++ b/absl/random/internal/sequence_urbg.h
@@ -0,0 +1,56 @@
+// Copyright 2017 The Abseil 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
+//
+// https://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.
+
+#ifndef ABSL_RANDOM_INTERNAL_SEQUENCE_URBG_H_
+#define ABSL_RANDOM_INTERNAL_SEQUENCE_URBG_H_
+
+#include <cstdint>
+#include <cstring>
+#include <limits>
+#include <type_traits>
+#include <vector>
+
+namespace absl {
+namespace random_internal {
+
+// `sequence_urbg` is a simple random number generator which meets the
+// requirements of [rand.req.urbg], and is solely for testing absl
+// distributions.
+class sequence_urbg {
+ public:
+ using result_type = uint64_t;
+
+ static constexpr result_type(min)() {
+ return (std::numeric_limits<result_type>::min)();
+ }
+ static constexpr result_type(max)() {
+ return (std::numeric_limits<result_type>::max)();
+ }
+
+ sequence_urbg(std::initializer_list<result_type> data) : i_(0), data_(data) {}
+ void reset() { i_ = 0; }
+
+ result_type operator()() { return data_[i_++ % data_.size()]; }
+
+ size_t invocations() const { return i_; }
+
+ private:
+ size_t i_;
+ std::vector<result_type> data_;
+};
+
+} // namespace random_internal
+} // namespace absl
+
+#endif // ABSL_RANDOM_INTERNAL_SEQUENCE_URBG_H_