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authorColin Cross <ccross@android.com>2022-04-13 03:15:00 +0000
committerAutomerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>2022-04-13 03:15:00 +0000
commit6c9587948173932b64d97c288a947e43d2a2ac14 (patch)
tree2ce94d7f0804ccb77d1fa9b2a1bca00eecdff1e2 /third_party/abseil-cpp/absl/cleanup/cleanup.h
parentf60eaea2240ba9e1c508e8e0c91d39ee9fc47be5 (diff)
parent43d8f56cdc20240b37c36bf417dd0d6999bce738 (diff)
downloadwebrtc-android13-d4-release.tar.gz
Merge changes I0ab600cd,I1e74c64a am: 798f3afdf6 am: 2f9c4b2c3b am: a9167328fc am: 7563023510 am: 43d8f56cdcandroid-13.0.0_r83android-13.0.0_r82android-13.0.0_r81android-13.0.0_r80android-13.0.0_r79android-13.0.0_r78android-13.0.0_r77android-13.0.0_r76android-13.0.0_r75android-13.0.0_r74android-13.0.0_r73android-13.0.0_r72android-13.0.0_r71android-13.0.0_r70android-13.0.0_r69android-13.0.0_r68android-13.0.0_r67android-13.0.0_r66android-13.0.0_r65android-13.0.0_r64android-13.0.0_r63android-13.0.0_r62android-13.0.0_r61android-13.0.0_r60android-13.0.0_r59android-13.0.0_r58android-13.0.0_r56android-13.0.0_r54android-13.0.0_r53android-13.0.0_r52android-13.0.0_r51android-13.0.0_r50android-13.0.0_r49android-13.0.0_r48android-13.0.0_r47android-13.0.0_r46android-13.0.0_r45android-13.0.0_r44android-13.0.0_r43android-13.0.0_r42android-13.0.0_r41android-13.0.0_r40android-13.0.0_r39android-13.0.0_r38android-13.0.0_r37android-13.0.0_r36android-13.0.0_r35android-13.0.0_r34android-13.0.0_r33android-13.0.0_r32android13-qpr3-s9-releaseandroid13-qpr3-s8-releaseandroid13-qpr3-s7-releaseandroid13-qpr3-s6-releaseandroid13-qpr3-s5-releaseandroid13-qpr3-s4-releaseandroid13-qpr3-s3-releaseandroid13-qpr3-s2-releaseandroid13-qpr3-s14-releaseandroid13-qpr3-s13-releaseandroid13-qpr3-s12-releaseandroid13-qpr3-s11-releaseandroid13-qpr3-s10-releaseandroid13-qpr3-s1-releaseandroid13-qpr3-releaseandroid13-qpr3-c-s8-releaseandroid13-qpr3-c-s7-releaseandroid13-qpr3-c-s6-releaseandroid13-qpr3-c-s5-releaseandroid13-qpr3-c-s4-releaseandroid13-qpr3-c-s3-releaseandroid13-qpr3-c-s2-releaseandroid13-qpr3-c-s12-releaseandroid13-qpr3-c-s11-releaseandroid13-qpr3-c-s10-releaseandroid13-qpr3-c-s1-releaseandroid13-qpr2-s9-releaseandroid13-qpr2-s8-releaseandroid13-qpr2-s7-releaseandroid13-qpr2-s6-releaseandroid13-qpr2-s5-releaseandroid13-qpr2-s3-releaseandroid13-qpr2-s2-releaseandroid13-qpr2-s12-releaseandroid13-qpr2-s11-releaseandroid13-qpr2-s10-releaseandroid13-qpr2-s1-releaseandroid13-qpr2-releaseandroid13-qpr2-b-s1-releaseandroid13-d4-s2-releaseandroid13-d4-s1-releaseandroid13-d4-release
Original change: https://android-review.googlesource.com/c/platform/external/webrtc/+/2062410 Change-Id: I1aa9f459b825711b800cc65782979943a9151ec7 Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
Diffstat (limited to 'third_party/abseil-cpp/absl/cleanup/cleanup.h')
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diff --git a/third_party/abseil-cpp/absl/cleanup/cleanup.h b/third_party/abseil-cpp/absl/cleanup/cleanup.h
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+++ b/third_party/abseil-cpp/absl/cleanup/cleanup.h
@@ -0,0 +1,140 @@
+// Copyright 2021 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.
+//
+// -----------------------------------------------------------------------------
+// File: cleanup.h
+// -----------------------------------------------------------------------------
+//
+// `absl::Cleanup` implements the scope guard idiom, invoking the contained
+// callback's `operator()() &&` on scope exit.
+//
+// Example:
+//
+// ```
+// absl::Status CopyGoodData(const char* source_path, const char* sink_path) {
+// FILE* source_file = fopen(source_path, "r");
+// if (source_file == nullptr) {
+// return absl::NotFoundError("No source file"); // No cleanups execute
+// }
+//
+// // C++17 style cleanup using class template argument deduction
+// absl::Cleanup source_closer = [source_file] { fclose(source_file); };
+//
+// FILE* sink_file = fopen(sink_path, "w");
+// if (sink_file == nullptr) {
+// return absl::NotFoundError("No sink file"); // First cleanup executes
+// }
+//
+// // C++11 style cleanup using the factory function
+// auto sink_closer = absl::MakeCleanup([sink_file] { fclose(sink_file); });
+//
+// Data data;
+// while (ReadData(source_file, &data)) {
+// if (!data.IsGood()) {
+// absl::Status result = absl::FailedPreconditionError("Read bad data");
+// return result; // Both cleanups execute
+// }
+// SaveData(sink_file, &data);
+// }
+//
+// return absl::OkStatus(); // Both cleanups execute
+// }
+// ```
+//
+// Methods:
+//
+// `std::move(cleanup).Cancel()` will prevent the callback from executing.
+//
+// `std::move(cleanup).Invoke()` will execute the callback early, before
+// destruction, and prevent the callback from executing in the destructor.
+//
+// Usage:
+//
+// `absl::Cleanup` is not an interface type. It is only intended to be used
+// within the body of a function. It is not a value type and instead models a
+// control flow construct. Check out `defer` in Golang for something similar.
+
+#ifndef ABSL_CLEANUP_CLEANUP_H_
+#define ABSL_CLEANUP_CLEANUP_H_
+
+#include <utility>
+
+#include "absl/base/config.h"
+#include "absl/base/macros.h"
+#include "absl/cleanup/internal/cleanup.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+
+template <typename Arg, typename Callback = void()>
+class ABSL_MUST_USE_RESULT Cleanup final {
+ static_assert(cleanup_internal::WasDeduced<Arg>(),
+ "Explicit template parameters are not supported.");
+
+ static_assert(cleanup_internal::ReturnsVoid<Callback>(),
+ "Callbacks that return values are not supported.");
+
+ public:
+ Cleanup(Callback callback) : storage_(std::move(callback)) {} // NOLINT
+
+ Cleanup(Cleanup&& other) = default;
+
+ void Cancel() && {
+ ABSL_HARDENING_ASSERT(storage_.IsCallbackEngaged());
+ storage_.DestroyCallback();
+ }
+
+ void Invoke() && {
+ ABSL_HARDENING_ASSERT(storage_.IsCallbackEngaged());
+ storage_.InvokeCallback();
+ storage_.DestroyCallback();
+ }
+
+ ~Cleanup() {
+ if (storage_.IsCallbackEngaged()) {
+ storage_.InvokeCallback();
+ storage_.DestroyCallback();
+ }
+ }
+
+ private:
+ cleanup_internal::Storage<Callback> storage_;
+};
+
+// `absl::Cleanup c = /* callback */;`
+//
+// C++17 type deduction API for creating an instance of `absl::Cleanup`
+#if defined(ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION)
+template <typename Callback>
+Cleanup(Callback callback) -> Cleanup<cleanup_internal::Tag, Callback>;
+#endif // defined(ABSL_HAVE_CLASS_TEMPLATE_ARGUMENT_DEDUCTION)
+
+// `auto c = absl::MakeCleanup(/* callback */);`
+//
+// C++11 type deduction API for creating an instance of `absl::Cleanup`
+template <typename... Args, typename Callback>
+absl::Cleanup<cleanup_internal::Tag, Callback> MakeCleanup(Callback callback) {
+ static_assert(cleanup_internal::WasDeduced<cleanup_internal::Tag, Args...>(),
+ "Explicit template parameters are not supported.");
+
+ static_assert(cleanup_internal::ReturnsVoid<Callback>(),
+ "Callbacks that return values are not supported.");
+
+ return {std::move(callback)};
+}
+
+ABSL_NAMESPACE_END
+} // namespace absl
+
+#endif // ABSL_CLEANUP_CLEANUP_H_