WIP

cmds/cmdbase/service_linux.go

@@ -0,0 +1,128 @@
+package cmdbase
+
+import (
+	"fmt"
+	"log/slog"
+	"os"
+	"os/exec"
+	"os/signal"
+	"syscall"
+
+	processInfo "github.com/shirou/gopsutil/process"
+
+	"github.com/safing/portmaster/base/log"
+)
+
+type LinuxSystemService struct {
+	instance ServiceInstance
+}
+
+func NewSystemService(instance ServiceInstance) *LinuxSystemService {
+	return &LinuxSystemService{instance: instance}
+}
+
+func (s *LinuxSystemService) Run() {
+	// Start instance.
+	err := s.instance.Start()
+	if err != nil {
+		slog.Error("failed to start", "err", err)
+
+		// Print stack on start failure, if enabled.
+		if PrintStackOnExit {
+			printStackTo(log.GlobalWriter, "PRINTING STACK ON START FAILURE")
+		}
+
+		os.Exit(1)
+	}
+
+	// Subscribe to signals.
+	signalCh := make(chan os.Signal, 1)
+	signal.Notify(
+		signalCh,
+		os.Interrupt,
+		syscall.SIGHUP,
+		syscall.SIGINT,
+		syscall.SIGTERM,
+		syscall.SIGQUIT,
+		syscall.SIGUSR1,
+	)
+
+	// Wait for shutdown signal.
+wait:
+	for {
+		select {
+		case <-s.instance.ShuttingDown():
+			break wait
+		case sig := <-signalCh:
+			// Only print and continue to wait if SIGUSR1
+			if sig == syscall.SIGUSR1 {
+				printStackTo(log.GlobalWriter, "PRINTING STACK ON REQUEST")
+				continue wait
+			} else {
+				// Trigger shutdown.
+				fmt.Printf(" <SIGNAL: %v>\n", sig) // CLI output.
+				slog.Warn("received stop signal", "signal", sig)
+				s.instance.Shutdown()
+				break wait
+			}
+		}
+	}
+
+	// Wait for shutdown to finish.
+
+	// Catch signals during shutdown.
+	// Force exit after 5 interrupts.
+	forceCnt := 5
+	for {
+		select {
+		case <-s.instance.ShutdownComplete():
+			return
+		case sig := <-signalCh:
+			if sig != syscall.SIGUSR1 {
+				forceCnt--
+				if forceCnt > 0 {
+					fmt.Printf(" <SIGNAL: %s> again, but already shutting down - %d more to force\n", sig, forceCnt)
+				} else {
+					printStackTo(log.GlobalWriter, "PRINTING STACK ON FORCED EXIT")
+					os.Exit(1)
+				}
+			}
+		}
+	}
+}
+
+func (s *LinuxSystemService) RestartService() error {
+	// Check if user defined custom command for restarting the service.
+	restartCommand, exists := os.LookupEnv("PORTMASTER_RESTART_COMMAND")
+
+	// Run the service restart
+	var cmd *exec.Cmd
+	if exists && restartCommand != "" {
+		slog.Debug("running custom restart command", "command", restartCommand)
+		cmd = exec.Command("sh", "-c", restartCommand)
+	} else {
+		cmd = exec.Command("systemctl", "restart", "portmaster")
+	}
+	if err := cmd.Start(); err != nil {
+		return fmt.Errorf("failed run restart command: %w", err)
+	}
+	return nil
+}
+
+func (s *LinuxSystemService) IsService() bool {
+	// Get own process ID
+	pid := os.Getpid()
+
+	// Get parent process ID.
+	currentProcess, err := processInfo.NewProcess(int32(pid)) //nolint:gosec
+	if err != nil {
+		return false
+	}
+	ppid, err := currentProcess.Ppid()
+	if err != nil {
+		return false
+	}
+
+	// Check if the parent process ID is 1 == init system
+	return ppid == 1
+}