diff options
author | Abseil Team <absl-team@google.com> | 2019-06-21T20·11-0700 |
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committer | Gennadiy Rozental <rogeeff@google.com> | 2019-06-21T20·18-0400 |
commit | e9324d926a9189e222741fce6e676f0944661a72 (patch) | |
tree | a08568a709940c376454da34c9d8aac021378e5f /absl/random/internal/explicit_seed_seq.h | |
parent | 43ef2148c0936ebf7cb4be6b19927a9d9d145b8f (diff) |
Export of internal Abseil changes.
-- 7a6ff16a85beb730c172d5d25cf1b5e1be885c56 by Laramie Leavitt <lar@google.com>: Internal change. PiperOrigin-RevId: 254454546 -- ff8f9bafaefc26d451f576ea4a06d150aed63f6f by Andy Soffer <asoffer@google.com>: Internal changes PiperOrigin-RevId: 254451562 -- deefc5b651b479ce36f0b4ef203e119c0c8936f2 by CJ Johnson <johnsoncj@google.com>: Account for subtracting unsigned values from the size of InlinedVector PiperOrigin-RevId: 254450625 -- 3c677316a27bcadc17e41957c809ca472d5fef14 by Andy Soffer <asoffer@google.com>: Add C++17's std::make_from_tuple to absl/utility/utility.h PiperOrigin-RevId: 254411573 -- 4ee3536a918830eeec402a28fc31a62c7c90b940 by CJ Johnson <johnsoncj@google.com>: Adds benchmark for the rest of the InlinedVector public API PiperOrigin-RevId: 254408378 -- e5a21a00700ee83498ff1efbf649169756463ee4 by CJ Johnson <johnsoncj@google.com>: Updates the definition of InlinedVector::shrink_to_fit() to be exception safe and adds exception safety tests for it. PiperOrigin-RevId: 254401387 -- 2ea82e72b86d82d78b4e4712a63a55981b53c64b by Laramie Leavitt <lar@google.com>: Use absl::InsecureBitGen in place of std::mt19937 in tests absl/random/...distribution_test.cc PiperOrigin-RevId: 254289444 -- fa099e02c413a7ffda732415e8105cad26a90337 by Andy Soffer <asoffer@google.com>: Internal changes PiperOrigin-RevId: 254286334 -- ce34b7f36933b30cfa35b9c9a5697a792b5666e4 by Andy Soffer <asoffer@google.com>: Internal changes PiperOrigin-RevId: 254273059 -- 6f9c473da7c2090c2e85a37c5f00622e8a912a89 by Jorg Brown <jorg@google.com>: Change absl::container_internal::CompressedTuple to instantiate its internal Storage class with the name of the type it's holding, rather than the name of the Tuple. This is not an externally-visible change, other than less compiler memory is used and less debug information is generated. PiperOrigin-RevId: 254269285 -- 8bd3c186bf2fc0c55d8a2dd6f28a5327502c9fba by Andy Soffer <asoffer@google.com>: Adding short-hand IntervalClosed for IntervalClosedClosed and IntervalOpen for IntervalOpenOpen. PiperOrigin-RevId: 254252419 -- ea957f99b6a04fccd42aa05605605f3b44b1ecfd by Abseil Team <absl-team@google.com>: Do not directly use __SIZEOF_INT128__. In order to avoid linker errors when building with clang-cl (__fixunsdfti, __udivti3 and __fixunssfti are undefined), this CL uses ABSL_HAVE_INTRINSIC_INT128 which is not defined for clang-cl. PiperOrigin-RevId: 254250739 -- 89ab385cd26b34d64130bce856253aaba96d2345 by Andy Soffer <asoffer@google.com>: Internal changes PiperOrigin-RevId: 254242321 -- cffc793d93eca6d6bdf7de733847b6ab4a255ae9 by CJ Johnson <johnsoncj@google.com>: Adds benchmark for InlinedVector::reserve(size_type) PiperOrigin-RevId: 254199226 -- c90c7a9fa3c8f0c9d5114036979548b055ea2f2a by Gennadiy Rozental <rogeeff@google.com>: Import of CCTZ from GitHub. PiperOrigin-RevId: 254072387 -- c4c388beae016c9570ab54ffa1d52660e4a85b7b by Laramie Leavitt <lar@google.com>: Internal cleanup. PiperOrigin-RevId: 254062381 -- d3c992e221cc74e5372d0c8fa410170b6a43c062 by Tom Manshreck <shreck@google.com>: Update distributions.h to Abseil standards PiperOrigin-RevId: 254054946 -- d15ad0035c34ef11b14fadc5a4a2d3ec415f5518 by CJ Johnson <johnsoncj@google.com>: Removes functions with only one caller from the implementation details of InlinedVector by manually inlining the definitions PiperOrigin-RevId: 254005427 -- 2f37e807efc3a8ef1f4b539bdd379917d4151520 by Andy Soffer <asoffer@google.com>: Initial release of Abseil Random PiperOrigin-RevId: 253999861 -- 24ed1694b6430791d781ed533a8f8ccf6cac5856 by CJ Johnson <johnsoncj@google.com>: Updates the definition of InlinedVector::assign(...)/InlinedVector::operator=(...) to new, exception-safe implementations with exception safety tests to boot PiperOrigin-RevId: 253993691 -- 5613d95f5a7e34a535cfaeadce801441e990843e by CJ Johnson <johnsoncj@google.com>: Adds benchmarks for InlinedVector::shrink_to_fit() PiperOrigin-RevId: 253989647 -- 2a96ddfdac40bbb8cb6a7f1aeab90917067c6e63 by Abseil Team <absl-team@google.com>: Initial release of Abseil Random PiperOrigin-RevId: 253927497 -- bf1aff8fc9ffa921ad74643e9525ecf25b0d8dc1 by Andy Soffer <asoffer@google.com>: Initial release of Abseil Random PiperOrigin-RevId: 253920512 -- bfc03f4a3dcda3cf3a4b84bdb84cda24e3394f41 by Laramie Leavitt <lar@google.com>: Internal change. PiperOrigin-RevId: 253886486 -- 05036cfcc078ca7c5f581a00dfb0daed568cbb69 by Eric Fiselier <ericwf@google.com>: Don't include `winsock2.h` because it drags in `windows.h` and friends, and they define awful macros like OPAQUE, ERROR, and more. This has the potential to break abseil users. Instead we only forward declare `timeval` and require Windows users include `winsock2.h` themselves. This is both inconsistent and poor QoI, but so including 'windows.h' is bad too. PiperOrigin-RevId: 253852615 GitOrigin-RevId: 7a6ff16a85beb730c172d5d25cf1b5e1be885c56 Change-Id: Icd6aff87da26f29ec8915da856f051129987cef6
Diffstat (limited to 'absl/random/internal/explicit_seed_seq.h')
-rw-r--r-- | absl/random/internal/explicit_seed_seq.h | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/absl/random/internal/explicit_seed_seq.h b/absl/random/internal/explicit_seed_seq.h new file mode 100644 index 000000000000..b660ece50017 --- /dev/null +++ b/absl/random/internal/explicit_seed_seq.h @@ -0,0 +1,87 @@ +// 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_EXPLICIT_SEED_SEQ_H_ +#define ABSL_RANDOM_INTERNAL_EXPLICIT_SEED_SEQ_H_ + +#include <algorithm> +#include <cstddef> +#include <cstdint> +#include <initializer_list> +#include <iterator> +#include <vector> + +namespace absl { +namespace random_internal { + +// This class conforms to the C++ Standard "Seed Sequence" concept +// [rand.req.seedseq]. +// +// An "ExplicitSeedSeq" is meant to provide a conformant interface for +// forwarding pre-computed seed material to the constructor of a class +// conforming to the "Uniform Random Bit Generator" concept. This class makes no +// attempt to mutate the state provided by its constructor, and returns it +// directly via ExplicitSeedSeq::generate(). +// +// If this class is asked to generate more seed material than was provided to +// the constructor, then the remaining bytes will be filled with deterministic, +// nonrandom data. +class ExplicitSeedSeq { + public: + using result_type = uint32_t; + + ExplicitSeedSeq() : state_() {} + + // Copy and move both allowed. + ExplicitSeedSeq(const ExplicitSeedSeq& other) = default; + ExplicitSeedSeq& operator=(const ExplicitSeedSeq& other) = default; + ExplicitSeedSeq(ExplicitSeedSeq&& other) = default; + ExplicitSeedSeq& operator=(ExplicitSeedSeq&& other) = default; + + template <typename Iterator> + ExplicitSeedSeq(Iterator begin, Iterator end) { + for (auto it = begin; it != end; it++) { + state_.push_back(*it & 0xffffffff); + } + } + + template <typename T> + ExplicitSeedSeq(std::initializer_list<T> il) + : ExplicitSeedSeq(il.begin(), il.end()) {} + + size_t size() const { return state_.size(); } + + template <typename OutIterator> + void param(OutIterator out) const { + std::copy(std::begin(state_), std::end(state_), out); + } + + template <typename OutIterator> + void generate(OutIterator begin, OutIterator end) { + for (size_t index = 0; begin != end; begin++) { + *begin = state_.empty() ? 0 : state_[index++]; + if (index >= state_.size()) { + index = 0; + } + } + } + + protected: + std::vector<uint32_t> state_; +}; + +} // namespace random_internal +} // namespace absl + +#endif // ABSL_RANDOM_INTERNAL_EXPLICIT_SEED_SEQ_H_ |