rv: added Off variable to shutdown pi if true.

cmd/rv/main.go

@@ -59,6 +59,7 @@ import (
 	"os"
 	"runtime/pprof"
 	"strconv"
+	"syscall"
 	"time"
 
 	"gopkg.in/natefinch/lumberjack.v2"
@@ -212,6 +213,14 @@ func run(rv *revid.Revid, ns *netsender.Sender, l *logger.Logger, nl *netlogger.
 		}
 		l.Log(logger.Debug, "got new vars", "vars", vars)
 
+		// Shutdown pi if variable 'Off' is found and set to true.
+		if v, ok := vars["Off"]; ok && v == "true" {
+			err = syscall.Reboot(syscall.LINUX_REBOOT_CMD_POWER_OFF)
+			if err != nil {
+				l.Log(logger.Error, "could not power off", "error", err)
+			}
+		}
+
 		// Configure revid based on the vars.
 		l.Log(logger.Debug, "updating revid's configuration")
 		err = rv.Update(vars)