1 // Copyright 2013 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "base/barrier_closure.h" 6 7 #include "base/atomic_ref_count.h" 8 #include "base/bind.h" 9 10 namespace { 11 12 // Maintains state for a BarrierClosure. 13 class BarrierInfo { 14 public: 15 BarrierInfo(int num_callbacks_left, const base::Closure& done_closure); 16 void Run(); 17 18 private: 19 base::AtomicRefCount num_callbacks_left_; 20 base::Closure done_closure_; 21 }; 22 23 BarrierInfo::BarrierInfo(int num_callbacks, const base::Closure& done_closure) 24 : num_callbacks_left_(num_callbacks), 25 done_closure_(done_closure) { 26 } 27 28 void BarrierInfo::Run() { 29 DCHECK(!base::AtomicRefCountIsZero(&num_callbacks_left_)); 30 if (!base::AtomicRefCountDec(&num_callbacks_left_)) { 31 done_closure_.Run(); 32 done_closure_.Reset(); 33 } 34 } 35 36 } // namespace 37 38 namespace base { 39 40 base::Closure BarrierClosure(int num_callbacks_left, 41 const base::Closure& done_closure) { 42 DCHECK(num_callbacks_left >= 0); 43 44 if (num_callbacks_left == 0) 45 done_closure.Run(); 46 47 return base::Bind(&BarrierInfo::Run, 48 base::Owned( 49 new BarrierInfo(num_callbacks_left, done_closure))); 50 } 51 52 } // namespace base 53
