1 /*
2  * Copyright (c) 2022 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *     http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #include "link_stack.h"
17 #include "ace_log.h"
18 
19 namespace OHOS {
20 namespace ACELite {
InitStack()21 void LinkStack::InitStack()
22 {
23     head_ = new StackNode(nullptr);
24     if (head_ == nullptr) {
25         HILOG_ERROR(HILOG_MODULE_ACE, "create head failed");
26         return;
27     }
28     top_ = head_;
29     count_ = 0;
30 }
31 
FreeNode()32 void LinkStack::FreeNode()
33 {
34     StackNode *tmp = head_;
35     count_ = 0;
36     while (tmp != nullptr) {
37         head_ = head_->GetNodeNext();
38         delete tmp;
39         tmp = head_;
40     }
41     top_ = nullptr;
42 }
43 
IsEmpty() const44 bool LinkStack::IsEmpty() const
45 {
46     return head_ == top_;
47 }
48 
IsFull() const49 bool LinkStack::IsFull() const
50 {
51     return maxSize_ > 0 && count_ >= maxSize_;
52 }
53 
Push(const char * value)54 bool LinkStack::Push(const char *value)
55 {
56     if (value == nullptr || top_ == nullptr) {
57         return false;
58     }
59     if (IsFull()) {
60         HILOG_ERROR(HILOG_MODULE_ACE, "stack is full");
61         return false;
62     }
63 
64     StackNode *node = new StackNode(value);
65     if (node == nullptr) {
66         return false;
67     }
68 
69     top_->SetNodeNext(node);
70     node->SetNodePrev(top_);
71     count_++;
72     top_ = top_->GetNodeNext();
73     return true;
74 }
75 
Pop(const char ** value)76 bool LinkStack::Pop(const char **value)
77 {
78     if (top_ == nullptr || IsEmpty()) {
79         return false;
80     }
81     StackNode *tmp = top_;
82     if (value != nullptr) {
83         *value = top_->GetNodeData();
84     }
85     top_->SetNodeData(nullptr);
86     top_ = top_->GetNodePrev();
87     delete tmp;
88     tmp = nullptr;
89     top_->SetNodeNext(nullptr);
90     count_--;
91     return true;
92 }
93 } // namespace ACELite
94 } // namespace OHOS
95