1// Copyright 2015 the V8 project 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#ifndef V8_LOCKED_QUEUE_INL_H_
6#define V8_LOCKED_QUEUE_INL_H_
7
8#include "src/base/atomic-utils.h"
9#include "src/locked-queue.h"
10
11namespace v8 {
12namespace internal {
13
14template <typename Record>
15struct LockedQueue<Record>::Node : Malloced {
16 Node() : next(nullptr) {}
17 Record value;
18 base::AtomicValue<Node*> next;
19};
20
21
22template <typename Record>
23inline LockedQueue<Record>::LockedQueue() {
24 head_ = new Node();
25 CHECK_NOT_NULL(head_);
26 tail_ = head_;
27}
28
29
30template <typename Record>
31inline LockedQueue<Record>::~LockedQueue() {
32 // Destroy all remaining nodes. Note that we do not destroy the actual values.
33 Node* old_node = nullptr;
34 Node* cur_node = head_;
35 while (cur_node != nullptr) {
36 old_node = cur_node;
37 cur_node = cur_node->next.Value();
38 delete old_node;
39 }
40}
41
42
43template <typename Record>
44inline void LockedQueue<Record>::Enqueue(const Record& record) {
45 Node* n = new Node();
46 CHECK_NOT_NULL(n);
47 n->value = record;
48 {
49 base::MutexGuard guard(&tail_mutex_);
50 tail_->next.SetValue(n);
51 tail_ = n;
52 }
53}
54
55
56template <typename Record>
57inline bool LockedQueue<Record>::Dequeue(Record* record) {
58 Node* old_head = nullptr;
59 {
60 base::MutexGuard guard(&head_mutex_);
61 old_head = head_;
62 Node* const next_node = head_->next.Value();
63 if (next_node == nullptr) return false;
64 *record = next_node->value;
65 head_ = next_node;
66 }
67 delete old_head;
68 return true;
69}
70
71
72template <typename Record>
73inline bool LockedQueue<Record>::IsEmpty() const {
74 base::MutexGuard guard(&head_mutex_);
75 return head_->next.Value() == nullptr;
76}
77
78
79template <typename Record>
80inline bool LockedQueue<Record>::Peek(Record* record) const {
81 base::MutexGuard guard(&head_mutex_);
82 Node* const next_node = head_->next.Value();
83 if (next_node == nullptr) return false;
84 *record = next_node->value;
85 return true;
86}
87
88} // namespace internal
89} // namespace v8
90
91#endif // V8_LOCKED_QUEUE_INL_H_
92