Handle signal preventing Start from completing

In the instance where the user sends a signal, such as SIGINT (Ctl-c)
when a Podman Machine is in the middle of starting, make sure the state
doesn't get stuck in the "Currently Starting" status.

Resolves: #24416

Signed-off-by: Jake Correnti <[email protected]>

Author: jakecorrenti

pkg/machine/shim/host.go

@@ -6,10 +6,12 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"os/signal"
 	"path"
 	"path/filepath"
 	"runtime"
 	"strings"
+	"syscall"
 	"time"
 
 	"github.com/containers/podman/v5/pkg/machine"
@@ -440,6 +442,7 @@ func stopLocked(mc *vmconfigs.MachineConfig, mp vmconfigs.VMProvider, dirs *mach
 func Start(mc *vmconfigs.MachineConfig, mp vmconfigs.VMProvider, dirs *machineDefine.MachineDirs, opts machine.StartOptions) error {
 	defaultBackoff := 500 * time.Millisecond
 	maxBackoffs := 6
+	signalChanClosed := false
 
 	mc.Lock()
 	defer mc.Unlock()
@@ -471,17 +474,41 @@ func Start(mc *vmconfigs.MachineConfig, mp vmconfigs.VMProvider, dirs *machineDe
 		}
 	}
 
+	// if the machine cannot continue starting due to a signal, ensure the state
+	// reflects the machine is no longer starting
+	signalChan := make(chan os.Signal, 1)
+	signal.Notify(signalChan, os.Interrupt, syscall.SIGTERM)
+	go func() {
+		sig, ok := <-signalChan
+		if ok {
+			mc.Starting = false
+			logrus.Error("signal received when starting the machine: ", sig)
+
+			if err := mc.Write(); err != nil {
+				logrus.Error(err)
+			}
+
+			os.Exit(1)
+		}
+	}()
+
 	// Set starting to true
 	mc.Starting = true
 	if err := mc.Write(); err != nil {
 		logrus.Error(err)
 	}
+
 	// Set starting to false on exit
 	defer func() {
 		mc.Starting = false
 		if err := mc.Write(); err != nil {
 			logrus.Error(err)
 		}
+
+		if !signalChanClosed {
+			signal.Stop(signalChan)
+			close(signalChan)
+		}
 	}()
 
 	gvproxyPidFile, err := dirs.RuntimeDir.AppendToNewVMFile("gvproxy.pid", nil)
@@ -557,6 +584,11 @@ func Start(mc *vmconfigs.MachineConfig, mp vmconfigs.VMProvider, dirs *machineDe
 		return errors.New(msg)
 	}
 
+	// now that the machine has transitioned into the running state, we don't need a goroutine listening for SIGINT or SIGTERM to handle state
+	signal.Stop(signalChan)
+	close(signalChan)
+	signalChanClosed = true
+
 	if err := proxyenv.ApplyProxies(mc); err != nil {
 		return err
 	}