xref: /aosp_15_r20/external/openscreen/osp/impl/service_publisher_impl.cc (revision 3f982cf4871df8771c9d4abe6e9a6f8d829b2736) 
1 // Copyright 2018 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 "osp/impl/service_publisher_impl.h"
6 
7 #include <utility>
8 
9 #include "util/osp_logging.h"
10 
11 namespace openscreen {
12 namespace osp {
13 namespace {
14 
IsTransitionValid(ServicePublisher::State from,ServicePublisher::State to)15 bool IsTransitionValid(ServicePublisher::State from,
16                        ServicePublisher::State to) {
17   using State = ServicePublisher::State;
18   switch (from) {
19     case State::kStopped:
20       return to == State::kStarting || to == State::kStopping;
21     case State::kStarting:
22       return to == State::kRunning || to == State::kStopping ||
23              to == State::kSuspended;
24     case State::kRunning:
25       return to == State::kSuspended || to == State::kStopping;
26     case State::kStopping:
27       return to == State::kStopped;
28     case State::kSuspended:
29       return to == State::kRunning || to == State::kStopping;
30     default:
31       OSP_DCHECK(false) << "unknown State value: " << static_cast<int>(from);
32       break;
33   }
34   return false;
35 }
36 
37 }  // namespace
38 
39 ServicePublisherImpl::Delegate::Delegate() = default;
40 ServicePublisherImpl::Delegate::~Delegate() = default;
41 
SetPublisherImpl(ServicePublisherImpl * publisher)42 void ServicePublisherImpl::Delegate::SetPublisherImpl(
43     ServicePublisherImpl* publisher) {
44   OSP_DCHECK(!publisher_);
45   publisher_ = publisher;
46 }
47 
ServicePublisherImpl(Observer * observer,std::unique_ptr<Delegate> delegate)48 ServicePublisherImpl::ServicePublisherImpl(Observer* observer,
49                                            std::unique_ptr<Delegate> delegate)
50     : ServicePublisher(observer), delegate_(std::move(delegate)) {
51   delegate_->SetPublisherImpl(this);
52 }
53 
54 ServicePublisherImpl::~ServicePublisherImpl() = default;
55 
Start()56 bool ServicePublisherImpl::Start() {
57   if (state_ != State::kStopped)
58     return false;
59   state_ = State::kStarting;
60   delegate_->StartPublisher(config_);
61   return true;
62 }
StartAndSuspend()63 bool ServicePublisherImpl::StartAndSuspend() {
64   if (state_ != State::kStopped)
65     return false;
66   state_ = State::kStarting;
67   delegate_->StartAndSuspendPublisher(config_);
68   return true;
69 }
Stop()70 bool ServicePublisherImpl::Stop() {
71   if (state_ == State::kStopped || state_ == State::kStopping)
72     return false;
73 
74   state_ = State::kStopping;
75   delegate_->StopPublisher();
76   return true;
77 }
Suspend()78 bool ServicePublisherImpl::Suspend() {
79   if (state_ != State::kRunning && state_ != State::kStarting)
80     return false;
81 
82   delegate_->SuspendPublisher();
83   return true;
84 }
Resume()85 bool ServicePublisherImpl::Resume() {
86   if (state_ != State::kSuspended)
87     return false;
88 
89   delegate_->ResumePublisher(config_);
90   return true;
91 }
92 
SetState(State state)93 void ServicePublisherImpl::SetState(State state) {
94   OSP_DCHECK(IsTransitionValid(state_, state));
95   state_ = state;
96   if (observer_)
97     MaybeNotifyObserver();
98 }
99 
MaybeNotifyObserver()100 void ServicePublisherImpl::MaybeNotifyObserver() {
101   OSP_DCHECK(observer_);
102   switch (state_) {
103     case State::kRunning:
104       observer_->OnStarted();
105       break;
106     case State::kStopped:
107       observer_->OnStopped();
108       break;
109     case State::kSuspended:
110       observer_->OnSuspended();
111       break;
112     default:
113       break;
114   }
115 }
116 
117 }  // namespace osp
118 }  // namespace openscreen
119