diff options
author | Abseil Team <absl-team@google.com> | 2020-09-18 15:55:15 -0700 |
---|---|---|
committer | Derek Mauro <dmauro@google.com> | 2020-09-24 13:47:15 -0400 |
commit | b56cbdd23834a65682c0b46f367f8679e83bc894 (patch) | |
tree | dacab9a64dd1a9e9668737e511d1a5420ff96001 /absl/random/internal/distribution_caller.h | |
parent | b832dce8489ef7b6231384909fd9b68d5a5ff2b7 (diff) |
Abseil LTS 2020092320200923
What's New:
* `absl::StatusOr<T>` has been released. See our [blog
post](https://abseil.io/blog/2020-091021-status) for more
information.
* Abseil Flags reflection interfaces have been released.
* Abseil Flags memory usage has been significantly optimized.
* Abseil now supports a "hardened" build mode. This build mode enables
runtime checks that guard against programming errors that may lead
to security vulnerabilities.
Notable Fixes:
* Sanitizer dynamic annotations like `AnnotateRWLockCreate` that are
also defined by the compiler sanitizer implementation are no longer
also defined by Abseil.
* Sanitizer macros are now prefixed with `ABSL_` to avoid naming collisions.
* Sanitizer usage is now automatically detected and no longer requires
macros like `ADDRESS_SANITIZER` to be defined on the command line.
Breaking Changes:
* Abseil no longer contains a `dynamic_annotations` library. Users
using a supported build system (Bazel or CMake) are unaffected by
this, but users manually specifying link libraries may get an error
about a missing linker input.
Baseline: 7680a5f8efe32de4753baadbd63e74e59d95bac1
Cherry picks: None
Diffstat (limited to 'absl/random/internal/distribution_caller.h')
-rw-r--r-- | absl/random/internal/distribution_caller.h | 66 |
1 files changed, 49 insertions, 17 deletions
diff --git a/absl/random/internal/distribution_caller.h b/absl/random/internal/distribution_caller.h index 02603cf8..fc81b787 100644 --- a/absl/random/internal/distribution_caller.h +++ b/absl/random/internal/distribution_caller.h @@ -20,6 +20,8 @@ #include <utility> #include "absl/base/config.h" +#include "absl/base/internal/fast_type_id.h" +#include "absl/utility/utility.h" namespace absl { ABSL_NAMESPACE_BEGIN @@ -30,27 +32,57 @@ namespace random_internal { // to intercept such calls. template <typename URBG> struct DistributionCaller { - // Call the provided distribution type. The parameters are expected - // to be explicitly specified. - // DistrT is the distribution type. - // FormatT is the formatter type: + // SFINAE to detect whether the URBG type includes a member matching + // bool InvokeMock(base_internal::FastTypeIdType, void*, void*). // - // struct FormatT { - // using result_type = distribution_t::result_type; - // static std::string FormatCall( - // const distribution_t& distr, - // absl::Span<const result_type>); - // - // static std::string FormatExpectation( - // absl::string_view match_args, - // absl::Span<const result_t> results); - // } - // - template <typename DistrT, typename FormatT, typename... Args> - static typename DistrT::result_type Call(URBG* urbg, Args&&... args) { + // These live inside BitGenRef so that they have friend access + // to MockingBitGen. (see similar methods in DistributionCaller). + template <template <class...> class Trait, class AlwaysVoid, class... Args> + struct detector : std::false_type {}; + template <template <class...> class Trait, class... Args> + struct detector<Trait, absl::void_t<Trait<Args...>>, Args...> + : std::true_type {}; + + template <class T> + using invoke_mock_t = decltype(std::declval<T*>()->InvokeMock( + std::declval<::absl::base_internal::FastTypeIdType>(), + std::declval<void*>(), std::declval<void*>())); + + using HasInvokeMock = typename detector<invoke_mock_t, void, URBG>::type; + + // Default implementation of distribution caller. + template <typename DistrT, typename... Args> + static typename DistrT::result_type Impl(std::false_type, URBG* urbg, + Args&&... args) { DistrT dist(std::forward<Args>(args)...); return dist(*urbg); } + + // Mock implementation of distribution caller. + // The underlying KeyT must match the KeyT constructed by MockOverloadSet. + template <typename DistrT, typename... Args> + static typename DistrT::result_type Impl(std::true_type, URBG* urbg, + Args&&... args) { + using ResultT = typename DistrT::result_type; + using ArgTupleT = std::tuple<absl::decay_t<Args>...>; + using KeyT = ResultT(DistrT, ArgTupleT); + + ArgTupleT arg_tuple(std::forward<Args>(args)...); + ResultT result; + if (!urbg->InvokeMock(::absl::base_internal::FastTypeId<KeyT>(), &arg_tuple, + &result)) { + auto dist = absl::make_from_tuple<DistrT>(arg_tuple); + result = dist(*urbg); + } + return result; + } + + // Default implementation of distribution caller. + template <typename DistrT, typename... Args> + static typename DistrT::result_type Call(URBG* urbg, Args&&... args) { + return Impl<DistrT, Args...>(HasInvokeMock{}, urbg, + std::forward<Args>(args)...); + } }; } // namespace random_internal |