libcamera  v0.4.0
Supporting cameras in Linux since 2019
thread.h
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1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2 /*
3  * Copyright (C) 2019, Google Inc.
4  *
5  * Thread support
6  */
7 
8 #pragma once
9 
10 #include <memory>
11 #include <sys/types.h>
12 #include <thread>
13 
14 #include <libcamera/base/private.h>
15 
16 #include <libcamera/base/message.h>
17 #include <libcamera/base/signal.h>
18 #include <libcamera/base/span.h>
19 #include <libcamera/base/utils.h>
20 
21 namespace libcamera {
22 
23 class EventDispatcher;
24 class Message;
25 class Object;
26 class ThreadData;
27 class ThreadMain;
28 
29 class Thread
30 {
31 public:
32  Thread();
33  virtual ~Thread();
34 
35  void start();
36  void exit(int code = 0);
37  bool wait(utils::duration duration = utils::duration::max());
38 
39  int setThreadAffinity(const Span<const unsigned int> &cpus);
40 
41  bool isRunning();
42 
44 
45  static Thread *current();
46  static pid_t currentId();
47 
49 
50  void dispatchMessages(Message::Type type = Message::Type::None);
51 
52 protected:
53  int exec();
54  virtual void run();
55 
56 private:
57  void startThread();
58  void finishThread();
59 
60  void setThreadAffinityInternal();
61 
62  void postMessage(std::unique_ptr<Message> msg, Object *receiver);
63  void removeMessages(Object *receiver);
64 
65  friend class Object;
66  friend class ThreadData;
67  friend class ThreadMain;
68 
69  void moveObject(Object *object);
70  void moveObject(Object *object, ThreadData *currentData,
71  ThreadData *targetData);
72 
73  std::thread thread_;
74  ThreadData *data_;
75 };
76 
77 } /* namespace libcamera */
bool wait(utils::duration duration=utils::duration::max())
Wait for the thread to finish.
Definition: thread.cpp:394
static Thread * current()
Retrieve the Thread instance for the current thread.
Definition: thread.cpp:487
EventDispatcher * eventDispatcher()
Retrieve the event dispatcher.
Definition: thread.cpp:519
Top-level libcamera namespace.
Definition: backtrace.h:17
Interface to manage the libcamera events and timers.
Definition: event_dispatcher.h:17
Message queue support.
Thread-local internal data.
Definition: thread.cpp:105
A thread of execution.
Definition: thread.h:29
static pid_t currentId()
Retrieve the ID of the current thread.
Definition: thread.cpp:503
int setThreadAffinity(const Span< const unsigned int > &cpus)
Set the CPU affinity mask of the thread.
Definition: thread.cpp:428
Miscellaneous utility functions.
virtual void run()
Main function of the thread.
Definition: thread.cpp:336
Signal & slot implementation.
bool isRunning()
Check if the thread is running.
Definition: thread.cpp:471
void dispatchMessages(Message::Type type=Message::Type::None)
Dispatch posted messages for this thread.
Definition: thread.cpp:620
std::chrono::steady_clock::duration duration
The libcamera duration related to libcamera::utils::clock.
Definition: utils.h:72
int exec()
Enter the event loop.
Definition: thread.cpp:302
void exit(int code=0)
Stop the thread&#39;s event loop.
Definition: thread.cpp:369
Thread()
Create a thread.
Definition: thread.cpp:233
Generic signal and slot communication mechanism.
Definition: object.h:20
Signal finished
Signal the end of thread execution.
Definition: thread.h:43
void start()
Start the thread.
Definition: thread.cpp:248
Type
The message type.
Definition: message.h:26
Base object to support automatic signal disconnection.
Definition: object.h:24
Thread wrapper for the main thread.
Definition: thread.cpp:139