Use systemd for stopping lokinet, also some DRY

src/process/LokinetProcessManager.cpp

@@ -65,6 +65,22 @@ bool LokinetProcessManager::stopLokinetProcess()
         qDebug("warning, lokinet process is already stopping, we'll try to stop again anyway");
     }
 
+    bool success = doStopLokinetProcess();
+    if (not success)
+    {
+        qDebug() << "doStopLokinetProcess() failed";
+        return false;
+    }
+
+    // note that we don't touch m_didLaunchProcess here because we don't
+    // know whether or not lokinet will gracefully exit
+
+    setLastKnownStatus(ProcessStatus::Stopping);
+    return true;
+}
+
+bool LokinetProcessManager::doStopLokinetProcess()
+{
     bool success = m_apiClient.llarpAdminDie([](QNetworkReply* reply) {
         qDebug() << "llarp.admin.die response: " << reply->readAll();
     });
@@ -74,11 +90,7 @@ bool LokinetProcessManager::stopLokinetProcess()
         return false;
     }
 
-    // note that we don't touch m_didLaunchProcess here because we don't
-    // know whether or not lokinet will gracefully exit
-
-    setLastKnownStatus(ProcessStatus::Stopping);
-    return true;
+    return success;
 }
 
 bool LokinetProcessManager::forciblyStopLokinetProcess()

src/process/LokinetProcessManager.hpp

@@ -138,6 +138,16 @@ protected:
      */
     virtual bool doStartLokinetProcess() = 0;
     
+    /**
+     * Subclasses may provide platform-specific means of stopping the
+     * lokinet process. Note, however, that this has an "intelligent default"
+     * which will use the 'llarp.admin.die' API call, which should cause
+     * lokinet to gracefully exit.
+     *
+     * @return true on successful request to stop, false otherwise
+     */
+    virtual bool doStopLokinetProcess();
+    
     /**
      * Subclasses should provide platform-specific means of forcibly stopping
      * the lokinet process.

src/process/SystemdLokinetProcessManager.cpp

@@ -26,32 +26,36 @@ SystemdStatus fromString(const QString& str) {
     return SystemdStatus::unknown;
 }
 
-bool SystemdLokinetProcessManager::doStartLokinetProcess()
+bool invoke(const QString& cmd, const QStringList& args)
 {
-    QStringList args = { "--noblock", "start", "lokinet.service" };
-    int result = QProcess::execute("systemctl", args);
+    int result = QProcess::execute(cmd, args);
     if (result)
     {
-        qDebug("Failed to 'systemctl start lokinet': %d", result);
+        qDebug() << "Failed to invoke " << cmd;
+        qDebug() << "    Args:";
+        for (const auto arg : args)
+        {
+            qDebug() << "        " << arg;
+        }
         return false;
     }
 
     return true;
 }
 
+bool SystemdLokinetProcessManager::doStopLokinetProcess()
+{
+    return invoke("systemctl", { "--no-block", "stop", "lokinet.service" });
+}
+
+bool SystemdLokinetProcessManager::doStartLokinetProcess()
+{
+    return invoke("systemctl", { "--no-block", "start", "lokinet.service" });
+}
+
 bool SystemdLokinetProcessManager::doForciblyStopLokinetProcess()
 {
-    // note that this will do its own graceful attempt before doing a forceful kill.
-    // "kill" instead of "stop" should perform an immediate, forceful kill
-    QStringList args = { "stop", "lokinet.service" };
-    int result = QProcess::execute("systemctl", args);
-    if (result)
-    {
-        qDebug("Failed to 'systemctl stop lokinet': %d", result);
-        return false;
-    }
-
-    return true;
+    return invoke("systemctl", { "--noblock", "kill", "lokinet.service" });
 }
 
 bool SystemdLokinetProcessManager::doGetProcessPid(int& pid)

src/process/SystemdLokinetProcessManager.hpp

@@ -15,6 +15,7 @@ class SystemdLokinetProcessManager : public LokinetProcessManager
 
 protected:
     
+    bool doStopLokinetProcess() override;
     bool doStartLokinetProcess() override;
     bool doForciblyStopLokinetProcess() override;
     bool doGetProcessPid(int& pid) override;