[RPC] Add an uptime command that displays the amount of time that bitcoind has been running

src/rpc/server.cpp

@@ -258,6 +258,22 @@ UniValue stop(const JSONRPCRequest& jsonRequest)
     return "Bitcoin server stopping";
 }
 
+UniValue uptime(const JSONRPCRequest& jsonRequest)
+{
+    if (jsonRequest.fHelp || jsonRequest.params.size() > 1)
+        throw std::runtime_error(
+                "uptime\n"
+                        "\nReturns the total uptime of the server.\n"
+                        "\nResult:\n"
+                        "ttt        (numeric) The number of seconds that the server has been running\n"
+                        "\nExamples:\n"
+                + HelpExampleCli("uptime", "")
+                + HelpExampleRpc("uptime", "")
+        );
+
+    return GetTime() - GetStartupTime();
+}
+
 /**
  * Call Table
  */
@@ -267,6 +283,7 @@ static const CRPCCommand vRPCCommands[] =
     /* Overall control/query calls */
     { "control",            "help",                   &help,                   true,  {"command"}  },
     { "control",            "stop",                   &stop,                   true,  {}  },
+    { "control",            "uptime",                 &uptime,                 true,  {}  },
 };
 
 CRPCTable::CRPCTable()