Better logging + runVM impl

cmd/utils.go

@@ -1,10 +1,14 @@
 package cmd
 
 import (
-	"fmt"
+	"context"
 	"os"
 	"os/user"
+	"sync"
 
+	"log/slog"
+
+	"github.com/AlexSSD7/vldisk/vm"
 	"github.com/pkg/errors"
 )
 
@@ -19,12 +23,76 @@ func checkIfRoot() (bool, error) {
 func doRootCheck() {
 	ok, err := checkIfRoot()
 	if err != nil {
-		fmt.Printf("Failed to check whether the command is ran by root: %v.\n", err)
+		slog.Error("Failed to check whether the command is ran by root", "error", err.Error())
 		os.Exit(1)
 	}
 
 	if !ok {
-		fmt.Printf("Root permissions are required.\n")
+		slog.Error("You must run this program as root")
 		os.Exit(1)
 	}
 }
+
+func runVM(passthroughArg string, fn func(context.Context, *vm.Instance, *vm.FileManager)) *vm.Instance {
+	doRootCheck()
+
+	passthroughConfig := getDevicePassthroughConfig(passthroughArg)
+
+	// TODO: Alpine image should be downloaded from somewhere.
+	vi, err := vm.NewInstance(slog.Default(), "alpine-img/alpine.qcow2", []vm.USBDevicePassthroughConfig{passthroughConfig}, true)
+	if err != nil {
+		slog.Error("Failed to create vm instance", "error", err.Error())
+		os.Exit(1)
+	}
+
+	runErrCh := make(chan error, 1)
+	var wg sync.WaitGroup
+
+	ctx, ctxCancel := context.WithCancel(context.Background())
+
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+
+		err := vi.Run()
+		ctxCancel()
+		runErrCh <- err
+	}()
+
+	fm := vm.NewFileManager(vi)
+
+	for {
+		select {
+		case err := <-runErrCh:
+			slog.Error("Failed to start the VM", "error", err.Error())
+			os.Exit(1)
+		case <-vi.SSHUpNotifyChan():
+			err := fm.Init()
+			if err != nil {
+				slog.Error("Failed to initialize File Manager", "error", err.Error())
+				os.Exit(1)
+			}
+
+			fn(ctx, vi, fm)
+
+			err = vi.Cancel()
+			if err != nil {
+				slog.Error("Failed to cancel VM context", "error", err.Error())
+				os.Exit(1)
+			}
+
+			wg.Wait()
+
+			select {
+			case err := <-runErrCh:
+				if err != nil {
+					slog.Error("Failed to run the VM", "error", err.Error())
+					os.Exit(1)
+				}
+			default:
+			}
+
+			return nil
+		}
+	}
+}