| // Copyright 2020 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include <iostream> |
| #include <memory> |
| #include <string> |
| |
| #include "include/cppgc/allocation.h" |
| #include "include/cppgc/default-platform.h" |
| #include "include/cppgc/garbage-collected.h" |
| #include "include/cppgc/heap.h" |
| #include "include/cppgc/member.h" |
| #include "include/cppgc/visitor.h" |
| |
| #if !CPPGC_IS_STANDALONE |
| #include "include/v8-initialization.h" |
| #endif // !CPPGC_IS_STANDALONE |
| |
| /** |
| * This sample program shows how to set up a stand-alone cppgc heap. |
| */ |
| |
| /** |
| * Simple string rope to illustrate allocation and garbage collection below. |
| * The rope keeps the next parts alive via regular managed reference. |
| */ |
| class Rope final : public cppgc::GarbageCollected<Rope> { |
| public: |
| explicit Rope(std::string part, Rope* next = nullptr) |
| : part_(std::move(part)), next_(next) {} |
| |
| void Trace(cppgc::Visitor* visitor) const { visitor->Trace(next_); } |
| |
| private: |
| const std::string part_; |
| const cppgc::Member<Rope> next_; |
| |
| friend std::ostream& operator<<(std::ostream& os, const Rope& rope) { |
| os << rope.part_; |
| if (rope.next_) { |
| os << *rope.next_; |
| } |
| return os; |
| } |
| }; |
| |
| int main(int argc, char* argv[]) { |
| // Create a default platform that is used by cppgc::Heap for execution and |
| // backend allocation. |
| auto cppgc_platform = std::make_shared<cppgc::DefaultPlatform>(); |
| #if !CPPGC_IS_STANDALONE |
| // When initializing a stand-alone cppgc heap in a regular V8 build, the |
| // internal V8 platform will be reused. Reusing the V8 platform requires |
| // initializing it properly. |
| v8::V8::InitializePlatform(cppgc_platform->GetV8Platform()); |
| #endif // !CPPGC_IS_STANDALONE |
| // Initialize the process. This must happen before any cppgc::Heap::Create() |
| // calls. |
| cppgc::DefaultPlatform::InitializeProcess(cppgc_platform.get()); |
| { |
| // Create a managed heap. |
| std::unique_ptr<cppgc::Heap> heap = cppgc::Heap::Create(cppgc_platform); |
| // Allocate a string rope on the managed heap. |
| Rope* greeting = cppgc::MakeGarbageCollected<Rope>( |
| heap->GetAllocationHandle(), "Hello ", |
| cppgc::MakeGarbageCollected<Rope>(heap->GetAllocationHandle(), |
| "World!")); |
| // Manually trigger garbage collection. The object greeting is held alive |
| // through conservative stack scanning. |
| heap->ForceGarbageCollectionSlow("CppGC example", "Testing"); |
| std::cout << *greeting << std::endl; |
| } |
| // Gracefully shutdown the process. |
| cppgc::ShutdownProcess(); |
| return 0; |
| } |