1 /*
2  * Copyright (c) 2021 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 "thread_ex.h"
17 #include <sys/resource.h>
18 #include <sys/prctl.h>
19 #include <iostream>
20 #include "utils_log.h"
21 
22 namespace OHOS {
23 using ThreadFunc = int (*)(void*);
24 using PThreadRoutine = void* (*) (void*);
25 
26 struct ThreadParam {
27     ThreadFunc startRoutine;
28     void* args;
29     int priority;
30     std::string name;
31 
32     // prctl only support set the name of the calling process.
ProxyOHOS::ThreadParam33     static int Proxy(const ThreadParam* t)
34     {
35         if (t == nullptr) {
36             UTILS_LOGD("invalid param.");
37             return -1;
38         }
39         ThreadFunc f = t->startRoutine;
40         void* userData = t->args;
41         int prio = t->priority;
42         std::string threadName = t->name;
43 
44         delete t;
45 
46         // set thread priority
47         (void)setpriority(PRIO_PROCESS, 0, prio);
48 
49         // set thread name
50         if (!threadName.empty()) {
51             prctl(PR_SET_NAME, threadName.substr(0, MAX_THREAD_NAME_LEN).c_str(), 0, 0, 0);
52         }
53 
54         return f(userData);
55     }
56 };
57 
CreatePThread(ThreadParam & para,size_t stackSize,pthread_t * threadId)58 bool CreatePThread(ThreadParam& para, size_t stackSize, pthread_t *threadId)
59 
60 {
61     pthread_attr_t attr;
62     pthread_attr_init(&attr);
63 
64     // create thread as "detached", so it cleans up after itself.
65     pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
66 
67     auto t = new ThreadParam; // t would be delete in ThreadParam::Proxy
68     t->startRoutine = para.startRoutine;
69     t->args = para.args;
70     t->priority = para.priority;
71     t->name = para.name;
72 
73     para.startRoutine = reinterpret_cast<ThreadFunc>(&ThreadParam::Proxy);
74     para.args = t;
75 
76     if (stackSize) {
77         pthread_attr_setstacksize(&attr, stackSize);
78     }
79 
80     errno = 0;
81     pthread_t thread;
82     int result = pthread_create(&thread, &attr, reinterpret_cast<PThreadRoutine>(para.startRoutine), para.args);
83     pthread_attr_destroy(&attr);
84     para.args = nullptr;
85 
86     if (result != 0) {
87         return false;
88     }
89 
90     if (threadId != nullptr) {
91         *threadId = thread;
92     }
93 
94     return true;
95 }
96 
Thread()97 Thread::Thread()
98     : thread_(INVALID_PTHREAD_T), status_(ThreadStatus::OK), exitPending_(false), running_(false)
99 {
100 }
101 
~Thread()102 Thread::~Thread()
103 {
104 }
105 
Start(const std::string & name,int32_t priority,size_t stack)106 ThreadStatus Thread::Start(const std::string& name, int32_t priority, size_t stack)
107 {
108     std::lock_guard<std::mutex> lk(lock_);
109     if (running_) {
110         // already started
111         return ThreadStatus::INVALID_OPERATION;
112     }
113 
114     status_ = ThreadStatus::OK;
115     exitPending_ = false;
116     thread_ = INVALID_PTHREAD_T;
117     running_ = true;
118 
119     ThreadParam para;
120     para.startRoutine = ThreadStart;
121     para.args = this;
122     para.name = name;
123     para.priority = priority;
124 
125     bool res = CreatePThread(para, stack, &thread_);
126     if (!res) {
127         status_ = ThreadStatus::UNKNOWN_ERROR;   // something happened!
128         running_ = false;
129         thread_ = INVALID_PTHREAD_T;
130         return ThreadStatus::UNKNOWN_ERROR;
131     }
132 
133     return ThreadStatus::OK;
134 }
135 
NotifyExitSync()136 ThreadStatus Thread::NotifyExitSync()
137 {
138     // If the two thread IDs are equal, pthread_equal() returns a non-zero value; otherwise, it returns 0.
139     if (pthread_equal(thread_, pthread_self()) != 0) {
140         // don't call NotifyExitSync() from this !;
141         return ThreadStatus::WOULD_BLOCK;
142     }
143 
144     std::unique_lock<std::mutex> lk(lock_);
145     exitPending_ = true;
146 
147     while (running_) {
148         cvThreadExited_.wait(lk);
149     }
150 
151     exitPending_ = false;
152 
153     return status_;
154 }
155 
NotifyExitAsync()156 void Thread::NotifyExitAsync()
157 {
158     std::lock_guard<std::mutex> lk(lock_);
159     exitPending_ = true;
160 }
161 
ReadyToWork()162 bool Thread::ReadyToWork()
163 {
164     return true;
165 }
166 
IsExitPending() const167 bool Thread::IsExitPending() const
168 {
169     std::lock_guard<std::mutex> lk(lock_);
170     return exitPending_;
171 }
172 
IsRunning() const173 bool Thread::IsRunning() const
174 {
175     std::lock_guard<std::mutex> lk(lock_);
176     return running_;
177 }
178 
ThreadStart(void * args)179 int Thread::ThreadStart(void* args)
180 {
181     Thread* const self = static_cast<Thread*>(args);
182     bool first = true;
183 
184     do {
185         bool result = false;
186         if (first) {
187             first = false;
188             if (self->ReadyToWork() && !self->IsExitPending()) {
189                 result = self->Run();
190             }
191         } else {
192             result = self->Run();
193         }
194 
195         {
196             std::unique_lock<std::mutex> lk(self->lock_);
197             if ((!result) || self->exitPending_) {
198                 self->exitPending_ = true;
199                 self->running_ = false;
200                 self->thread_ = INVALID_PTHREAD_T;
201                 self->cvThreadExited_.notify_all();
202                 break;
203             }
204         }
205     } while (true);
206 
207     return 0;
208 }
209 
210 } // namespace OHOS
211