958 lines
26 KiB
C++
958 lines
26 KiB
C++
/*
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* flow.h
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*
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* This source file is part of the FoundationDB open source project
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*
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* Copyright 2013-2018 Apple Inc. and the FoundationDB project authors
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifndef FLOW_FLOW_H
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#define FLOW_FLOW_H
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#pragma once
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#pragma warning( disable: 4244 4267 ) // SOMEDAY: Carefully check for integer overflow issues (e.g. size_t to int conversions like this suppresses)
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#pragma warning( disable: 4345 )
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#pragma warning( error: 4239 )
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#include <vector>
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#include <queue>
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#include <map>
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#include <unordered_map>
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#include <set>
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#include <functional>
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#include <iostream>
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#include <string>
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#include <utility>
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#include <algorithm>
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#include "flow/Platform.h"
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#include "flow/FastAlloc.h"
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#include "flow/IRandom.h"
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#include "flow/serialize.h"
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#include "flow/Deque.h"
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#include "flow/ThreadPrimitives.h"
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#include "flow/network.h"
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using namespace std::rel_ops;
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#define TEST( condition ) if (!(condition)); else { static TraceEvent* __test = &(TraceEvent("CodeCoverage").detail("File", __FILE__).detail("Line",__LINE__).detail("Condition", #condition)); }
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/*
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usage:
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if (BUGGIFY) (
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// code here is executed on some runs (with probability P_BUGGIFIED_SECTION_ACTIVATED),
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// sometimes --
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)
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*/
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extern double P_BUGGIFIED_SECTION_ACTIVATED, P_BUGGIFIED_SECTION_FIRES, P_EXPENSIVE_VALIDATION;
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int getSBVar(std::string file, int line);
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void enableBuggify(bool enabled); // Currently controls buggification and (randomized) expensive validation
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bool validationIsEnabled();
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#define BUGGIFY_WITH_PROB(x) (getSBVar(__FILE__, __LINE__) && g_random->random01() < (x))
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#define BUGGIFY BUGGIFY_WITH_PROB(P_BUGGIFIED_SECTION_FIRES)
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#define EXPENSIVE_VALIDATION (validationIsEnabled() && g_random->random01() < P_EXPENSIVE_VALIDATION)
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extern Optional<uint64_t> parse_with_suffix(std::string toparse, std::string default_unit = "");
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extern std::string format(const char* form, ...);
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// On success, returns the number of characters written. On failure, returns a negative number.
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extern int vsformat(std::string &outputString, const char* form, va_list args);
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extern Standalone<StringRef> strinc(StringRef const& str);
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extern StringRef strinc(StringRef const& str, Arena& arena);
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extern Standalone<StringRef> addVersionStampAtEnd(StringRef const& str);
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extern StringRef addVersionStampAtEnd(StringRef const& str, Arena& arena);
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template <typename Iter>
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StringRef concatenate( Iter b, Iter const& e, Arena& arena ) {
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int rsize = 0;
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Iter i = b;
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while(i != e) {
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rsize += i->size();
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++i;
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}
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uint8_t* s = new (arena) uint8_t[ rsize ];
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uint8_t* p = s;
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while(b != e) {
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memcpy(p, b->begin(),b->size());
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p += b->size();
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++b;
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}
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return StringRef(s, rsize);
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}
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template <typename Iter>
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Standalone<StringRef> concatenate( Iter b, Iter const& e ) {
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Standalone<StringRef> r;
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((StringRef &)r) = concatenate(b, e, r.arena());
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return r;
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}
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class Void {
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public:
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template <class Ar>
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void serialize(Ar&) {}
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};
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class Never {};
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template <class T>
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class Optional {
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public:
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Optional() : valid(false) {}
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Optional(const Optional<T>& o) : valid(o.valid) {
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if (valid) new (&value) T(o.get());
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}
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template <class U>
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Optional(const U& t) : valid(true) { new (&value) T(t); }
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/* This conversion constructor was nice, but combined with the prior constructor it means that Optional<int> can be converted to Optional<Optional<int>> in the wrong way
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(a non-present Optional<int> converts to a non-present Optional<Optional<int>>).
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Use .cast_to<>() instead.
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template <class S> Optional(const Optional<S>& o) : valid(o.present()) { if (valid) new (&value) T(o.get()); } */
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Optional(Arena& a, const Optional<T>& o) : valid(o.valid) {
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if (valid) new (&value) T(a, o.get());
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}
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int expectedSize() const { return valid ? get().expectedSize() : 0; }
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template <class R> Optional<R> cast_to() const {
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if (present())
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return Optional<R>(get());
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else
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return Optional<R>();
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}
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~Optional() {
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if (valid) ((T*)&value)->~T();
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}
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Optional & operator=(Optional const& o) {
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if (valid) {
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valid = false;
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((T*)&value)->~T();
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}
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if (o.valid) {
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new (&value) T(o.get());
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valid = true;
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}
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return *this;
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}
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bool present() const { return valid; }
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T& get() {
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UNSTOPPABLE_ASSERT(valid);
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return *(T*)&value;
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}
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T const& get() const {
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UNSTOPPABLE_ASSERT(valid);
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return *(T const*)&value;
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}
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T orDefault(T const& default_value) const { if (valid) return get(); else return default_value; }
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template <class Ar>
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void serialize(Ar& ar) {
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// SOMEDAY: specialize for space efficiency?
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if (valid && Ar::isDeserializing)
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(*(T *)&value).~T();
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ar & valid;
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if (valid) {
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if (Ar::isDeserializing) new (&value) T();
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ar & *(T*)&value;
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}
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}
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bool operator == (Optional const& o) const {
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return present() == o.present() && (!present() || get() == o.get());
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}
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bool operator != (Optional const& o) const {
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return !(*this == o);
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}
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// Ordering: If T is ordered, then Optional() < Optional(t) and (Optional(u)<Optional(v))==(u<v)
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bool operator < (Optional const& o) const {
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if (present() != o.present()) return o.present();
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if (!present()) return false;
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return get() < o.get();
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}
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private:
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typename std::aligned_storage< sizeof(T), __alignof(T) >::type value;
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bool valid;
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};
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template <class T>
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class ErrorOr {
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public:
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ErrorOr() : error(default_error_or()) {}
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ErrorOr(Error const& error) : error(error) {}
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ErrorOr(const ErrorOr<T>& o) : error(o.error) {
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if (present()) new (&value) T(o.get());
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}
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template <class U>
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ErrorOr(const U& t) : error() { new (&value) T(t); }
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ErrorOr(Arena& a, const ErrorOr<T>& o) : error(o.error) {
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if (present()) new (&value) T(a, o.get());
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}
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int expectedSize() const { return present() ? get().expectedSize() : 0; }
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template <class R> ErrorOr<R> cast_to() const {
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if (present())
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return ErrorOr<R>(get());
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else
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return ErrorOr<R>();
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}
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~ErrorOr() {
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if (present()) ((T*)&value)->~T();
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}
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ErrorOr & operator=(ErrorOr const& o) {
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if (present()) {
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((T*)&value)->~T();
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}
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if (o.present()) {
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new (&value) T(o.get());
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}
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error = o.error;
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return *this;
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}
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bool present() const { return error.code() == invalid_error_code; }
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T& get() {
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UNSTOPPABLE_ASSERT(present());
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return *(T*)&value;
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}
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T const& get() const {
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UNSTOPPABLE_ASSERT(present());
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return *(T const*)&value;
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}
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T orDefault(T const& default_value) const { if (present()) return get(); else return default_value; }
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template <class Ar>
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void serialize(Ar& ar) {
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// SOMEDAY: specialize for space efficiency?
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ar & error;
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if (present()) {
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if (Ar::isDeserializing) new (&value) T();
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ar & *(T*)&value;
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}
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}
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bool operator == (ErrorOr const& o) const {
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return error == o.error && (!present() || get() == o.get());
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}
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bool operator != (ErrorOr const& o) const {
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return !(*this == o);
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}
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bool operator < (ErrorOr const& o) const {
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if (error != o.error) return error < o.error;
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if (!present()) return false;
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return get() < o.get();
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}
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bool isError() const { return error.code() != invalid_error_code; }
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bool isError(int code) const { return error.code() == code; }
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Error getError() const { ASSERT(isError()); return error; }
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private:
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typename std::aligned_storage< sizeof(T), __alignof(T) >::type value;
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Error error;
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};
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template <class T>
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struct Callback {
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Callback<T> *prev, *next;
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virtual void fire(T const&) {}
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virtual void error(Error) {}
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virtual void unwait() {}
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void insert(Callback<T>* into) {
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// Add this (uninitialized) callback just after `into`
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this->prev = into;
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this->next = into->next;
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into->next->prev = this;
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into->next = this;
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}
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void insertBack(Callback<T>* into) {
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// Add this (uninitialized) callback just before `into`
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this->next = into;
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this->prev = into->prev;
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into->prev->next = this;
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into->prev = this;
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}
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void insertChain(Callback<T>* into) {
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// Combine this callback's (initialized) chain and `into`'s such that this callback is just after `into`
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auto p = this->prev;
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auto n = into->next;
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this->prev = into;
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into->next = this;
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p->next = n;
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n->prev = p;
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}
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void remove() {
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// Remove this callback from the list it is in, and call unwait() on the head of that list if this was the last callback
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next->prev = prev;
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prev->next = next;
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if (prev == next)
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next->unwait();
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}
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int countCallbacks() {
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int count = 0;
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for (Callback* c = next; c != this; c = c->next)
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count++;
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return count;
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}
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};
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template <class T>
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struct SingleCallback {
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// Used for waiting on FutureStreams, which don't support multiple callbacks
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SingleCallback<T> *next;
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virtual void fire(T const&) {}
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virtual void error(Error) {}
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virtual void unwait() {}
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void insert(SingleCallback<T>* into) {
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this->next = into->next;
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into->next = this;
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}
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void remove() {
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ASSERT(next->next == this);
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next->next = next;
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next->unwait();
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}
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};
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template <class T>
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struct SAV : private Callback<T>, FastAllocated<SAV<T>> {
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int promises; // one for each promise (and one for an active actor if this is an actor)
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int futures; // one for each future and one more if there are any callbacks
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private:
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typename std::aligned_storage< sizeof(T), __alignof(T) >::type value_storage;
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public:
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Error error_state;
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enum { UNSET_ERROR_CODE = -3, NEVER_ERROR_CODE, SET_ERROR_CODE };
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T& value() { return *(T*)&value_storage; }
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SAV(int futures, int promises) : futures(futures), promises(promises), error_state(Error::fromCode(UNSET_ERROR_CODE)) {
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Callback<T>::prev = Callback<T>::next = this;
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}
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~SAV() {
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if (int16_t(error_state.code()) == SET_ERROR_CODE)
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value().~T();
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}
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bool isSet() const { return int16_t(error_state.code()) > NEVER_ERROR_CODE; }
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bool canBeSet() const { return int16_t(error_state.code()) == UNSET_ERROR_CODE; }
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bool isError() const { return int16_t(error_state.code()) > SET_ERROR_CODE; }
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T const& get() {
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ASSERT(isSet());
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if (isError()) throw error_state;
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return value();
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}
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template <class U>
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void send(U && value) {
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ASSERT(canBeSet());
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new (&value_storage) T(std::forward<U>(value));
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this->error_state = Error::fromCode(SET_ERROR_CODE);
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while (Callback<T>::next != this)
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Callback<T>::next->fire(this->value());
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}
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void send(Never) {
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ASSERT(canBeSet());
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this->error_state = Error::fromCode(NEVER_ERROR_CODE);
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}
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void sendError(Error err) {
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ASSERT(canBeSet() && int16_t(err.code()) > 0);
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this->error_state = err;
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while (Callback<T>::next != this)
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Callback<T>::next->error(err);
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}
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template <class U>
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void sendAndDelPromiseRef(U && value) {
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ASSERT(canBeSet());
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if (promises == 1 && !futures) {
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// No one is left to receive the value, so we can just die
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destroy();
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return;
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}
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new (&value_storage) T(std::forward<U>(value));
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finishSendAndDelPromiseRef();
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}
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void finishSendAndDelPromiseRef() {
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// Call only after value_storage has already been initialized!
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this->error_state = Error::fromCode(SET_ERROR_CODE);
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while (Callback<T>::next != this)
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Callback<T>::next->fire(this->value());
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if (!--promises && !futures)
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destroy();
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}
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void sendAndDelPromiseRef(Never) {
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ASSERT(canBeSet());
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this->error_state = Error::fromCode(NEVER_ERROR_CODE);
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if (!--promises && !futures)
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destroy();
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}
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void sendErrorAndDelPromiseRef(Error err) {
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ASSERT(canBeSet() && int16_t(err.code()) > 0);
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if (promises == 1 && !futures) {
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// No one is left to receive the value, so we can just die
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destroy();
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return;
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}
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this->error_state = err;
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while (Callback<T>::next != this)
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Callback<T>::next->error(err);
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if (!--promises && !futures)
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destroy();
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}
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void addPromiseRef() { promises++; }
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void addFutureRef() { futures++; }
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void delPromiseRef() {
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if (promises == 1) {
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if (futures && canBeSet()) {
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sendError(broken_promise());
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ASSERT(promises == 1); // Once there is only one promise, there is no one else with the right to change the promise reference count
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}
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promises = 0;
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if (!futures)
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destroy();
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}
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else
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--promises;
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}
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void delFutureRef() {
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if (!--futures) {
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if (promises)
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cancel();
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else
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destroy();
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}
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}
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int getFutureReferenceCount() const { return futures; }
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int getPromiseReferenceCount() const { return promises; }
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virtual void destroy() { delete this; }
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virtual void cancel() {}
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void addCallbackAndDelFutureRef(Callback<T>* cb) {
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// We are always *logically* dropping one future reference from this, but if we are adding a first callback
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// we also need to add one (since futures is defined as being +1 if there are any callbacks), so net nothing
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if (Callback<T>::next != this)
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delFutureRef();
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cb->insert(this);
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}
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void addYieldedCallbackAndDelFutureRef(Callback<T>* cb) {
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// Same contract as addCallbackAndDelFutureRef, except that the callback is placed at the end of the callback chain rather than at the beginning
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if (Callback<T>::next != this)
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delFutureRef();
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cb->insertBack(this);
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}
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void addCallbackChainAndDelFutureRef(Callback<T>* cb) {
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if (Callback<T>::next != this)
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delFutureRef();
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cb->insertChain(this);
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}
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virtual void unwait() {
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delFutureRef();
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}
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virtual void fire() { ASSERT(false); }
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};
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template <class T>
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struct NotifiedQueue : private SingleCallback<T>, FastAllocated<NotifiedQueue<T>> {
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int promises; // one for each promise (and one for an active actor if this is an actor)
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int futures; // one for each future and one more if there are any callbacks
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// Invariant: SingleCallback<T>::next==this || (queue.empty() && !error.isValid())
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std::queue<T, Deque<T>> queue;
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Error error;
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NotifiedQueue(int futures, int promises) : futures(futures), promises(promises) {
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SingleCallback<T>::next = this;
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}
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bool isReady() const { return !queue.empty() || error.isValid(); }
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bool isError() const { return queue.empty() && error.isValid(); } // the *next* thing queued is an error
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T pop() {
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if (queue.empty()) {
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if (error.isValid()) throw error;
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throw internal_error();
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}
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auto copy = queue.front();
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queue.pop();
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return copy;
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}
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|
|
|
template <class U>
|
|
void send(U && value) {
|
|
if (error.isValid()) return;
|
|
|
|
if (SingleCallback<T>::next != this) {
|
|
SingleCallback<T>::next->fire(std::forward<U>(value));
|
|
}
|
|
else {
|
|
queue.emplace(std::forward<U>(value));
|
|
}
|
|
}
|
|
|
|
void sendError(Error err) {
|
|
if (error.isValid()) return;
|
|
|
|
this->error = err;
|
|
if (SingleCallback<T>::next != this)
|
|
SingleCallback<T>::next->error(err);
|
|
}
|
|
|
|
void addPromiseRef() { promises++; }
|
|
void addFutureRef() { futures++; }
|
|
|
|
void delPromiseRef() {
|
|
if (!--promises) {
|
|
if (futures) {
|
|
sendError(broken_promise());
|
|
}
|
|
else
|
|
destroy();
|
|
}
|
|
}
|
|
void delFutureRef() {
|
|
if (!--futures) {
|
|
if (promises)
|
|
cancel();
|
|
else
|
|
destroy();
|
|
}
|
|
}
|
|
|
|
int getFutureReferenceCount() const { return futures; }
|
|
int getPromiseReferenceCount() const { return promises; }
|
|
|
|
virtual void destroy() { delete this; }
|
|
virtual void cancel() {}
|
|
|
|
void addCallbackAndDelFutureRef(SingleCallback<T>* cb) {
|
|
ASSERT(SingleCallback<T>::next == this);
|
|
cb->insert(this);
|
|
}
|
|
virtual void unwait() {
|
|
delFutureRef();
|
|
}
|
|
virtual void fire() { ASSERT(false); }
|
|
};
|
|
|
|
|
|
template <class T>
|
|
class Promise;
|
|
|
|
template <class T>
|
|
class Future
|
|
{
|
|
public:
|
|
T const& get() const { return sav->get(); }
|
|
T getValue() const { return get(); }
|
|
|
|
bool isValid() const {
|
|
return sav != 0;
|
|
}
|
|
bool isReady() const {
|
|
return sav->isSet();
|
|
}
|
|
bool isError() const {
|
|
return sav->isError();
|
|
}
|
|
Error& getError() const {
|
|
ASSERT(isError());
|
|
return sav->error_state;
|
|
}
|
|
|
|
Future() : sav(0) {}
|
|
Future(const Future<T>& rhs) : sav(rhs.sav) {
|
|
if (sav) sav->addFutureRef();
|
|
//if (sav->endpoint.isValid()) cout << "Future copied for " << sav->endpoint.key << endl;
|
|
}
|
|
Future(Future<T>&& rhs) noexcept(true) : sav(rhs.sav) {
|
|
rhs.sav = 0;
|
|
//if (sav->endpoint.isValid()) cout << "Future moved for " << sav->endpoint.key << endl;
|
|
}
|
|
Future(const T& presentValue)
|
|
: sav(new SAV<T>(1, 0))
|
|
{
|
|
sav->send(presentValue);
|
|
}
|
|
Future(Never)
|
|
: sav(new SAV<T>(1, 0))
|
|
{
|
|
sav->send(Never());
|
|
}
|
|
Future(const Error& error)
|
|
: sav(new SAV<T>(1, 0))
|
|
{
|
|
sav->sendError(error);
|
|
}
|
|
|
|
~Future() {
|
|
//if (sav && sav->endpoint.isValid()) cout << "Future destroyed for " << sav->endpoint.key << endl;
|
|
if (sav) sav->delFutureRef();
|
|
}
|
|
void operator=(const Future<T>& rhs) {
|
|
if (rhs.sav) rhs.sav->addFutureRef();
|
|
if (sav) sav->delFutureRef();
|
|
sav = rhs.sav;
|
|
}
|
|
void operator=(Future<T>&& rhs) noexcept(true) {
|
|
if (sav != rhs.sav) {
|
|
if (sav) sav->delFutureRef();
|
|
sav = rhs.sav;
|
|
rhs.sav = 0;
|
|
}
|
|
}
|
|
bool operator == (const Future& rhs) { return rhs.sav == sav; }
|
|
bool operator != (const Future& rhs) { return rhs.sav != sav; }
|
|
|
|
void cancel() {
|
|
if (sav) sav->cancel();
|
|
}
|
|
|
|
void addCallbackAndClear(Callback<T>* cb) {
|
|
sav->addCallbackAndDelFutureRef(cb);
|
|
sav = 0;
|
|
}
|
|
|
|
void addYieldedCallbackAndClear(Callback<T>* cb) {
|
|
sav->addYieldedCallbackAndDelFutureRef(cb);
|
|
sav = 0;
|
|
}
|
|
|
|
void addCallbackChainAndClear(Callback<T>* cb) {
|
|
sav->addCallbackChainAndDelFutureRef(cb);
|
|
sav = 0;
|
|
}
|
|
|
|
int getFutureReferenceCount() const { return sav->getFutureReferenceCount(); }
|
|
int getPromiseReferenceCount() const { return sav->getPromiseReferenceCount(); }
|
|
|
|
explicit Future(SAV<T> * sav) : sav(sav) {
|
|
//if (sav->endpoint.isValid()) cout << "Future created for " << sav->endpoint.key << endl;
|
|
}
|
|
|
|
private:
|
|
SAV<T>* sav;
|
|
friend class Promise<T>;
|
|
};
|
|
|
|
// This class is used by the flow compiler when generating code around wait statements to avoid confusing situations
|
|
// regarding Futures.
|
|
//
|
|
// For example, the following is legal with Future but not with StrictFuture:
|
|
//
|
|
// Future<T> x = ...
|
|
// T result = wait(x); // This is the correct code
|
|
// Future<T> result = wait(x); // This is legal if wait() generates Futures, but it's probably wrong. It's a compilation error if wait() generates StrictFutures.
|
|
template <class T>
|
|
class StrictFuture : public Future<T> {
|
|
public:
|
|
inline StrictFuture(Future<T> const& f) : Future<T>(f) {}
|
|
inline StrictFuture(Never n) : Future<T>(n) {}
|
|
private:
|
|
StrictFuture(T t) {}
|
|
StrictFuture(Error e) {}
|
|
};
|
|
|
|
template <class T>
|
|
class Promise sealed
|
|
{
|
|
public:
|
|
template <class U>
|
|
void send(U && value) const {
|
|
sav->send(std::forward<U>(value));
|
|
}
|
|
template <class E>
|
|
void sendError(const E& exc) const { sav->sendError(exc); }
|
|
|
|
Future<T> getFuture() const { sav->addFutureRef(); return Future<T>(sav); }
|
|
bool isSet() { return sav->isSet(); }
|
|
bool canBeSet() { return sav->canBeSet(); }
|
|
bool isValid() const { return sav != NULL; }
|
|
Promise() : sav(new SAV<T>(0, 1)) {}
|
|
Promise(const Promise& rhs) : sav(rhs.sav) { sav->addPromiseRef(); }
|
|
Promise(Promise&& rhs) noexcept(true) : sav(rhs.sav) { rhs.sav = 0; }
|
|
~Promise() { if (sav) sav->delPromiseRef(); }
|
|
|
|
void operator=(const Promise& rhs) {
|
|
if (rhs.sav) rhs.sav->addPromiseRef();
|
|
if (sav) sav->delPromiseRef();
|
|
sav = rhs.sav;
|
|
}
|
|
void operator=(Promise && rhs) noexcept(true) {
|
|
if (sav != rhs.sav) {
|
|
if (sav) sav->delPromiseRef();
|
|
sav = rhs.sav;
|
|
rhs.sav = 0;
|
|
}
|
|
}
|
|
void reset() {
|
|
*this = Promise<T>();
|
|
}
|
|
void swap(Promise& other) {
|
|
std::swap(sav, other.sav);
|
|
}
|
|
|
|
// Beware, these operations are very unsafe
|
|
SAV<T>* extractRawPointer() { auto ptr = sav; sav = NULL; return ptr; }
|
|
explicit Promise<T>(SAV<T>* ptr) : sav(ptr) {}
|
|
|
|
int getFutureReferenceCount() const { return sav->getFutureReferenceCount(); }
|
|
int getPromiseReferenceCount() const { return sav->getPromiseReferenceCount(); }
|
|
|
|
private:
|
|
SAV<T> *sav;
|
|
};
|
|
|
|
|
|
template <class T>
|
|
class FutureStream {
|
|
public:
|
|
bool isValid() const {
|
|
return queue != 0;
|
|
}
|
|
bool isReady() const {
|
|
return queue->isReady();
|
|
}
|
|
bool isError() const {
|
|
// This means that the next thing to be popped is an error - it will be false if there is an error in the stream but some actual data first
|
|
return queue->isError();
|
|
}
|
|
void addCallbackAndClear(SingleCallback<T>* cb) {
|
|
queue->addCallbackAndDelFutureRef(cb);
|
|
queue = 0;
|
|
}
|
|
FutureStream() : queue(NULL) {}
|
|
FutureStream(const FutureStream& rhs) : queue(rhs.queue) { queue->addFutureRef(); }
|
|
FutureStream(FutureStream&& rhs) noexcept(true) : queue(rhs.queue) { rhs.queue = 0; }
|
|
~FutureStream() { if (queue) queue->delFutureRef(); }
|
|
void operator=(const FutureStream& rhs) {
|
|
rhs.queue->addFutureRef();
|
|
if (queue) queue->delFutureRef();
|
|
queue = rhs.queue;
|
|
}
|
|
void operator=(FutureStream&& rhs) noexcept(true) {
|
|
if (rhs.queue != queue) {
|
|
if (queue) queue->delFutureRef();
|
|
queue = rhs.queue;
|
|
rhs.queue = 0;
|
|
}
|
|
}
|
|
bool operator == (const FutureStream& rhs) { return rhs.queue == queue; }
|
|
bool operator != (const FutureStream& rhs) { return rhs.queue != queue; }
|
|
|
|
T pop() {
|
|
return queue->pop();
|
|
}
|
|
Error getError() {
|
|
ASSERT(queue->isError());
|
|
return queue->error;
|
|
}
|
|
|
|
explicit FutureStream(NotifiedQueue<T>* queue) : queue(queue) {}
|
|
|
|
private:
|
|
NotifiedQueue<T>* queue;
|
|
};
|
|
|
|
template <class Request>
|
|
decltype(fake<Request>().reply) const& getReplyPromise(Request const& r) { return r.reply; }
|
|
|
|
|
|
|
|
// Neither of these implementations of REPLY_TYPE() works on both MSVC and g++, so...
|
|
#ifdef __GNUG__
|
|
#define REPLY_TYPE(RequestType) decltype( getReplyPromise( fake<RequestType>() ).getFuture().getValue() )
|
|
//#define REPLY_TYPE(RequestType) decltype( getReplyFuture( fake<RequestType>() ).getValue() )
|
|
#else
|
|
template <class T>
|
|
struct ReplyType {
|
|
// Doing this calculation directly in the return value declaration for PromiseStream<T>::getReply()
|
|
// breaks IntelliSense in VS2010; this is a workaround.
|
|
typedef decltype(fake<T>().reply.getFuture().getValue()) Type;
|
|
};
|
|
template <class T> class ReplyPromise;
|
|
template <class T>
|
|
struct ReplyType<ReplyPromise<T>> {
|
|
typedef T Type;
|
|
};
|
|
#define REPLY_TYPE(RequestType) typename ReplyType<RequestType>::Type
|
|
#endif
|
|
|
|
|
|
|
|
|
|
template <class T>
|
|
class PromiseStream {
|
|
public:
|
|
// stream.send( request )
|
|
// Unreliable at most once delivery: Delivers request unless there is a connection failure (zero or one times)
|
|
|
|
void send(const T& value) const {
|
|
queue->send(value);
|
|
}
|
|
void sendError(const Error& error) const {
|
|
queue->sendError(error);
|
|
}
|
|
|
|
// stream.getReply( request )
|
|
// Reliable at least once delivery: Eventually delivers request at least once and returns one of the replies if communication is possible. Might deliver request
|
|
// more than once.
|
|
// If a reply is returned, request was or will be delivered one or more times.
|
|
// If cancelled, request was or will be delivered zero or more times.
|
|
template <class X>
|
|
Future<REPLY_TYPE(X)> getReply(const X& value) const {
|
|
send(value);
|
|
return getReplyPromise(value).getFuture();
|
|
}
|
|
template <class X>
|
|
Future<REPLY_TYPE(X)> getReply(const X& value, int taskID) const {
|
|
setReplyPriority(value, taskID);
|
|
return getReplyPromise(value).getFuture();
|
|
}
|
|
|
|
template <class X>
|
|
Future<X> getReply() const {
|
|
return getReply(Promise<X>());
|
|
}
|
|
template <class X>
|
|
Future<X> getReplyWithTaskID(int taskID) const {
|
|
Promise<X> reply;
|
|
reply.getEndpoint(taskID);
|
|
return getReply(reply);
|
|
}
|
|
|
|
FutureStream<T> getFuture() const { queue->addFutureRef(); return FutureStream<T>(queue); }
|
|
PromiseStream() : queue(new NotifiedQueue<T>(0, 1)) {}
|
|
PromiseStream(const PromiseStream& rhs) : queue(rhs.queue) { queue->addPromiseRef(); }
|
|
PromiseStream(PromiseStream&& rhs) noexcept(true) : queue(rhs.queue) { rhs.queue = 0; }
|
|
void operator=(const PromiseStream& rhs) {
|
|
rhs.queue->addPromiseRef();
|
|
if (queue) queue->delPromiseRef();
|
|
queue = rhs.queue;
|
|
}
|
|
void operator=(PromiseStream&& rhs) noexcept(true) {
|
|
if (queue != rhs.queue) {
|
|
if (queue) queue->delPromiseRef();
|
|
queue = rhs.queue;
|
|
rhs.queue = 0;
|
|
}
|
|
}
|
|
~PromiseStream() {
|
|
if (queue)
|
|
queue->delPromiseRef();
|
|
//queue = (NotifiedQueue<T>*)0xdeadbeef;
|
|
}
|
|
|
|
bool operator == (const PromiseStream<T>& rhs) const { return queue == rhs.queue; }
|
|
bool isEmpty() const { return !queue->isReady(); }
|
|
|
|
private:
|
|
NotifiedQueue<T>* queue;
|
|
};
|
|
|
|
|
|
//extern int actorCount;
|
|
|
|
template <class T>
|
|
static inline void destruct(T& t) {
|
|
t.~T();
|
|
}
|
|
|
|
template <class ReturnValue>
|
|
struct Actor : SAV<ReturnValue> {
|
|
int8_t actor_wait_state; // -1 means actor is cancelled; 0 means actor is not waiting; 1-N mean waiting in callback group #
|
|
|
|
Actor() : SAV<ReturnValue>(1, 1), actor_wait_state(0) { /*++actorCount;*/ }
|
|
//~Actor() { --actorCount; }
|
|
};
|
|
|
|
template <>
|
|
struct Actor<void> {
|
|
// This specialization is for a void actor (one not returning a future, hence also uncancellable)
|
|
|
|
int8_t actor_wait_state; // 0 means actor is not waiting; 1-N mean waiting in callback group #
|
|
|
|
Actor() : actor_wait_state(0) { /*++actorCount;*/ }
|
|
//~Actor() { --actorCount; }
|
|
};
|
|
|
|
template <class ActorType, int CallbackNumber, class ValueType>
|
|
struct ActorCallback : Callback<ValueType> {
|
|
virtual void fire(ValueType const& value) {
|
|
static_cast<ActorType*>(this)->a_callback_fire(this, value);
|
|
}
|
|
virtual void error(Error e) {
|
|
static_cast<ActorType*>(this)->a_callback_error(this, e);
|
|
}
|
|
};
|
|
|
|
template <class ActorType, int CallbackNumber, class ValueType>
|
|
struct ActorSingleCallback : SingleCallback<ValueType> {
|
|
virtual void fire(ValueType const& value) {
|
|
static_cast<ActorType*>(this)->a_callback_fire(this, value);
|
|
}
|
|
virtual void error(Error e) {
|
|
static_cast<ActorType*>(this)->a_callback_error(this, e);
|
|
}
|
|
};
|
|
inline double now() { return g_network->now(); }
|
|
inline Future<Void> delay(double seconds, int taskID = TaskDefaultDelay) { return g_network->delay(seconds, taskID); }
|
|
inline Future<Void> delayUntil(double time, int taskID = TaskDefaultDelay) { return g_network->delay(std::max(0.0, time - g_network->now()), taskID); }
|
|
inline Future<Void> delayJittered(double seconds, int taskID = TaskDefaultDelay) { return g_network->delay(seconds*(FLOW_KNOBS->DELAY_JITTER_OFFSET + FLOW_KNOBS->DELAY_JITTER_RANGE*g_random->random01()), taskID); }
|
|
inline Future<Void> yield(int taskID = TaskDefaultYield) { return g_network->yield(taskID); }
|
|
inline bool check_yield(int taskID = TaskDefaultYield) { return g_network->check_yield(taskID); }
|
|
#include "flow/genericactors.actor.h"
|
|
#endif
|