commit e1646276a815471e4b3510825c21293095fc322f
author Alexander Hansen <alexander.hansen@9elements.com> Fri Jul 25 11:47:17 2025 +0200
committer Alexander Hansen <alexander.hansen@9elements.com> Thu Jul 31 12:46:26 2025 +0200
tree e06283d963b2a30eab72f6c90413c1bf1c1c2c5e
parent 0a4bb2a943bf277a0f2a0559abbed244da2aec88

PowerStatusMonitor: create DBus match in ctor

On request [1], create this change to create the DBus match for our
power status monitor in its constructor.

We get rid of the invalid state of the match not existing and can drop a
check for it.

We can also drop a call in 'main' function previously used to initialize
the match. The public API of this class is simplified.

Tested: Inspection only.

References:
[1] https://gerrit.openbmc.org/c/openbmc/entity-manager/+/81483/comment/858d95be_e2f9f6b8/

Change-Id: Ib05941a90ba2520b25e2c2b1e9a1e325caa722ae
Signed-off-by: Alexander Hansen <alexander.hansen@9elements.com>

src/entity_manager/entity_manager.cpp

diff --git a/src/entity_manager/entity_manager.cpp b/src/entity_manager/entity_manager.cpp
index 83240be..09cc7ba 100644
--- a/src/entity_manager/entity_manager.cpp
+++ b/src/entity_manager/entity_manager.cpp
@@ -73,7 +73,7 @@
     objServer(sdbusplus::asio::object_server(systemBus, /*skipManager=*/true)),
     lastJson(nlohmann::json::object()),
     systemConfiguration(nlohmann::json::object()), io(io),
-    propertiesChangedTimer(io)
+    powerStatus(*systemBus), propertiesChangedTimer(io)
 {
     // All other objects that EntityManager currently support are under the
     // inventory subtree.

src/entity_manager/main.cpp

diff --git a/src/entity_manager/main.cpp b/src/entity_manager/main.cpp
index efcb4d0..6a98279 100644
--- a/src/entity_manager/main.cpp
+++ b/src/entity_manager/main.cpp
@@ -34,10 +34,6 @@
 
     em.handleCurrentConfigurationJson();
 
-    // some boards only show up after power is on, we want to not say they are
-    // removed until the same state happens
-    em.powerStatus.setupPowerMatch(em.systemBus);
-
     io.run();
 
     return 0;

src/entity_manager/power_status_monitor.cpp

diff --git a/src/entity_manager/power_status_monitor.cpp b/src/entity_manager/power_status_monitor.cpp
index 93617d2..b281602 100644
--- a/src/entity_manager/power_status_monitor.cpp
+++ b/src/entity_manager/power_status_monitor.cpp
@@ -15,12 +15,21 @@
 const static constexpr char* path = "/xyz/openbmc_project/state/host0";
 const static constexpr char* property = "CurrentHostState";
 
-bool PowerStatusMonitor::isPowerOn()
+PowerStatusMonitor::PowerStatusMonitor(sdbusplus::asio::connection& conn) :
+
+    powerMatch(static_cast<sdbusplus::bus_t&>(conn),
+               "type='signal',interface='" +
+                   std::string(em_utils::properties::interface) + "',path='" +
+                   std::string(power::path) + "',arg0='" +
+                   std::string(power::interface) + "'",
+               std::bind_front(&PowerStatusMonitor::handlePowerMatch, this))
+
 {
-    if (!powerMatch)
-    {
-        throw std::runtime_error("Power Match Not Created");
-    }
+    getInitialPowerStatus(conn);
+}
+
+bool PowerStatusMonitor::isPowerOn() const
+{
     return powerStatusOn;
 }
 
@@ -39,18 +48,10 @@
     }
 }
 
-void PowerStatusMonitor::setupPowerMatch(
-    const std::shared_ptr<sdbusplus::asio::connection>& conn)
+void PowerStatusMonitor::getInitialPowerStatus(
+    sdbusplus::asio::connection& conn)
 {
-    powerMatch = std::make_unique<sdbusplus::bus::match_t>(
-        static_cast<sdbusplus::bus_t&>(*conn),
-        "type='signal',interface='" +
-            std::string(em_utils::properties::interface) + "',path='" +
-            std::string(power::path) + "',arg0='" +
-            std::string(power::interface) + "'",
-        std::bind_front(&PowerStatusMonitor::handlePowerMatch, this));
-
-    conn->async_method_call(
+    conn.async_method_call(
         [this](boost::system::error_code ec,
                const std::variant<std::string>& state) {
             if (ec)

src/entity_manager/power_status_monitor.hpp

diff --git a/src/entity_manager/power_status_monitor.hpp b/src/entity_manager/power_status_monitor.hpp
index 0955607..b6fd272 100644
--- a/src/entity_manager/power_status_monitor.hpp
+++ b/src/entity_manager/power_status_monitor.hpp
@@ -9,15 +9,16 @@
 class PowerStatusMonitor
 {
   public:
-    bool isPowerOn();
-    void setupPowerMatch(
-        const std::shared_ptr<sdbusplus::asio::connection>& conn);
+    explicit PowerStatusMonitor(sdbusplus::asio::connection& conn);
+
+    bool isPowerOn() const;
 
   private:
     void handlePowerMatch(sdbusplus::message_t& message);
+    void getInitialPowerStatus(sdbusplus::asio::connection& conn);
 
     bool powerStatusOn = false;
-    std::unique_ptr<sdbusplus::bus::match_t> powerMatch = nullptr;
+    sdbusplus::bus::match_t powerMatch;
 };
 
 } // namespace power