phosphor-pid-control/hoststatemonitor.hpp at master · openbmc/phosphor-pid-control · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
#pragma once

#include <boost/container/flat_map.hpp>
#include <sdbusplus/bus.hpp>
#include <sdbusplus/bus/match.hpp>
#include <sdbusplus/message.hpp>
#include <xyz/openbmc_project/State/Host/common.hpp>

#include <functional>
#include <iostream>
#include <memory>
#include <string>
#include <variant>

using HostState = sdbusplus::common::xyz::openbmc_project::state::Host;

constexpr const char* PROPERTIES_INTERFACE = "org.freedesktop.DBus.Properties";
constexpr const char* HOST_STATE_PATH = "/xyz/openbmc_project/state/host0";

class HostStateMonitor
{
  public:
    static HostStateMonitor& getInstance();
    static HostStateMonitor& getInstance(sdbusplus::bus_t& bus);

    ~HostStateMonitor() = default;

    // Delete copy constructor and assignment operator
    HostStateMonitor(const HostStateMonitor&) = delete;
    HostStateMonitor& operator=(const HostStateMonitor&) = delete;

    // Delete move constructor and assignment operator for singleton
    HostStateMonitor(HostStateMonitor&&) = delete;
    HostStateMonitor& operator=(HostStateMonitor&&) = delete;

    void startMonitoring();
    void stopMonitoring();
    bool isPowerOn() const
    {
        return powerStatusOn;
    }

  private:
    explicit HostStateMonitor(sdbusplus::bus_t& bus);

    void handleStateChange(sdbusplus::message_t& message);
    void getInitialState();

    sdbusplus::bus_t& bus;
    bool powerStatusOn;
    std::unique_ptr<sdbusplus::bus::match_t> hostStateMatch;
};

// Implementation
inline HostStateMonitor& HostStateMonitor::getInstance()
{
    static sdbusplus::bus_t defaultBus = sdbusplus::bus::new_default();
    return getInstance(defaultBus);
}

inline HostStateMonitor& HostStateMonitor::getInstance(sdbusplus::bus_t& bus)
{
    static HostStateMonitor instance(bus);
    return instance;
}

inline HostStateMonitor::HostStateMonitor(sdbusplus::bus_t& bus) :
    bus(bus), powerStatusOn(false), hostStateMatch(nullptr)
{
    getInitialState();
}

inline void HostStateMonitor::startMonitoring()
{
    if (hostStateMatch == nullptr)
    {
        using namespace sdbusplus::bus::match::rules;

        hostStateMatch = std::make_unique<sdbusplus::bus::match_t>(
            bus,
            propertiesChangedNamespace(HOST_STATE_PATH, HostState::interface),
            [this](sdbusplus::message_t& message) {
                handleStateChange(message);
            });
    }
}

inline void HostStateMonitor::stopMonitoring()
{
    hostStateMatch.reset();
}

inline void HostStateMonitor::handleStateChange(sdbusplus::message_t& message)
{
    std::string objectName;
    boost::container::flat_map<std::string, std::variant<std::string>> values;

    try
    {
        message.read(objectName, values);

        auto findState =
            values.find(HostState::property_names::current_host_state);
        if (findState != values.end())
        {
            const std::string& stateValue =
                std::get<std::string>(findState->second);
            bool newPowerStatus = stateValue.ends_with(".Running");

            if (newPowerStatus != powerStatusOn)
            {
                powerStatusOn = newPowerStatus;
            }
        }
    }
    catch (const std::exception& e)
    {
        std::cerr << "Failed to handle host state change: " << e.what()
                  << std::endl;
    }
}

inline void HostStateMonitor::getInitialState()
{
    try
    {
        auto method =
            bus.new_method_call("xyz.openbmc_project.State.Host0",
                                HOST_STATE_PATH, PROPERTIES_INTERFACE, "Get");
        method.append(HostState::interface,
                      HostState::property_names::current_host_state);

        auto reply = bus.call(method);
        auto currentState = reply.unpack<std::variant<std::string>>();

        const std::string& stateValue = std::get<std::string>(currentState);
        powerStatusOn = stateValue.ends_with(".Running");
    }
    catch (const std::exception& e)
    {
        powerStatusOn = false;
    }
}