Mount local FS; get struct pointer so we can modify values

cmd/list.go

@@ -16,13 +16,13 @@ import (
 
 // Recurse into structure, returning reflect.Value of wanted field.
 //  Nested fields are named with a dot (ex "MyStruct.MyField")
-func getStructFieldValue(parentStruct interface{}, fieldName string) (reflect.Value, string, error) {
+func getStructFieldValue(parentStruct interface{}, fieldName string) (*reflect.Value, string, error) {
 	v := reflect.ValueOf(parentStruct)
 
-	if v.Kind() == reflect.Ptr {
+/*	if v.Kind() == reflect.Ptr {
 		v = v.Elem()
 	}
-
+*/
 	if false {
 		for i := 0 ; i < v.NumField(); i++ {
 			f := v.Field(i)
@@ -34,7 +34,8 @@ func getStructFieldValue(parentStruct interface{}, fieldName string) (reflect.Va
 
 	if strings.Contains(fieldName, ".") {
 		fs := strings.Split(fieldName, ".")
-		f := v.FieldByName(fs[0])
+		//f := v.FieldByName(fs[0])
+		f := v.Elem().FieldByName(fs[0])
 		if f.Kind() == reflect.Struct {
 			return getStructFieldValue(f.Interface(), strings.Join(fs[1:], "."))
 		} else {
@@ -43,13 +44,13 @@ func getStructFieldValue(parentStruct interface{}, fieldName string) (reflect.Va
 	} else {
 		f := v.FieldByName(fieldName)
 		if f.IsValid() {
-			return f, fieldName, nil
+			return &f, fieldName, nil
 		} else {
-			return v, fieldName, errors.New(fmt.Sprintf("Field not found: %s", fieldName))
+			return &v, fieldName, errors.New(fmt.Sprintf("Field not found: %s", fieldName))
 		}
 	}
 
-	return v, fieldName, nil
+	return &v, fieldName, nil
 }
 
 
@@ -365,7 +366,7 @@ func ListJails(args []string, display bool) {
 		js := initSortStruct()
 
 		// The way we manage criteria quantity is not very elegant...
-		var fct1, fct2, fct3 reflect.Value
+		var fct1, fct2, fct3 *reflect.Value
 		for i, c := range strings.Split(gSortFields, ",") {
 			var fctName string
 			if strings.HasPrefix(c, "-") {

cmd/root.go

@@ -3,14 +3,16 @@ package cmd
 import (
 	"os"
 	"fmt"
+	"strconv"
 	"strings"
+	"encoding/json"
 
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 )
 
 const (
-	version = "0.02"
+	gVersion = "0.022a"
 )
 
 var (
@@ -24,6 +26,8 @@ var (
 	gSortFields		string
 	gNoLineSep		bool
 
+	gHostVersion	float64
+
 
 	rootCmd = & cobra.Command{
     	Use:    "gocage",
@@ -33,6 +37,7 @@ It support iocage jails and can coexist with iocage.`,
 
 	    Run: func(cmd *cobra.Command, args []string) {
 	        fmt.Println("Here we are in the Run")
+			cleanAfterRun()
 	    },
 	}
 
@@ -41,7 +46,8 @@ It support iocage jails and can coexist with iocage.`,
 	    Short: "Print the version number of GoCage",
 	    Long:  `Let this show you how much fail I had to get this *cough* perfect`,
 	    Run: func(cmd *cobra.Command, args []string) {
-	        fmt.Printf("GoCage v.%s\n", version)
+	        fmt.Printf("GoCage v.%s on FreeBSD %.1f\n", gVersion, gHostVersion)
+			cleanAfterRun()
 	    },
 	}
 
@@ -53,6 +59,7 @@ Jail list can be restricted by adding name on command line
 ex: gocage list srv-db srv-web`,
 		Run: func(cmd *cobra.Command, args []string) {
 			ListJails(args, true)
+			cleanAfterRun()
 		},
 	}
 	
@@ -64,6 +71,7 @@ ex: gocage list srv-db srv-web`,
 			// Get the inventory
 			ListJails(args, false)
 			StopJail(args)
+			cleanAfterRun()
 		},
 	}
 
@@ -74,6 +82,7 @@ ex: gocage list srv-db srv-web`,
 			// Get the inventory
 			ListJails(args, false)
 			StartJail(args)
+			cleanAfterRun()
 		},
 	}
 )
@@ -98,6 +107,15 @@ func init() {
     rootCmd.AddCommand(listCmd)
     rootCmd.AddCommand(stopCmd)
     rootCmd.AddCommand(startCmd)
+
+	// Get FreeBSD version
+	out, err := executeCommand("freebsd-version")
+	if err != nil {
+		fmt.Printf("Error running \"freebsd-version\": %s", err.Error())
+		os.Exit(1)
+	}
+	gHostVersion, _ = strconv.ParseFloat(strings.Split(out, "-")[0], 32)
+
 }
 
 func initConfig() {
@@ -141,6 +159,21 @@ func initConfig() {
 	}
 }
 
+// Called after execution
+func cleanAfterRun() {
+	for _, j := range gJails {
+		if j.ConfigUpdated {
+			// TODO : Marshall to disk
+			fmt.Printf("Config for jail %s will be updated\n", j.Name)
+			marshaled, err := json.MarshalIndent(j.Config, "", "    ")
+			if err != nil {
+				fmt.Printf("ERROR marshaling config: %s\n", err.Error())
+			}
+			fmt.Printf(string(marshaled))
+		}
+	}
+}
+
 func Execute() {
     if err := rootCmd.Execute(); err != nil {
         fmt.Fprintln(os.Stderr, err)

cmd/start.go

@@ -9,8 +9,132 @@ import (
 //	"os/exec"
 //	"reflect"
 	"strings"
+//	"strconv"
 )
 
+// WIP. Not working now (need to address the real struct field, not a copy of it)
+// setJailProperty takes a string as propValue, whatever the real property type is.
+//  It will be converted.
+func setJailProperty(jail *Jail, propName string, propValue string) error {
+	// First get propName type, to convert propValue
+/*	k, _, err := getStructFieldKind(jail, propName)
+	if err != nil {
+		return err
+	}
+	kind := k.String()
+*/
+
+	for i, j := range gJails {
+		if j.Name == jail.Name {
+			val, _, err := getStructFieldValue(&gJails[i], propName)
+			if err != nil {
+				return errors.New(fmt.Sprintf("Field not found: %s", propName))
+			}
+
+			/*if kind == "string" {
+			// WIll the affectation be done in source object or a copy?
+				val.Set(propValue)
+			} else if kind == "int" {
+				v, err := strconv.Atoi(propValue)
+				if err != nil {
+					return errors.New(fmt.Sprintf("propValue have wrong type: %s\n", err.Error()))
+				}
+				val.Set(v)
+			} else {
+				return errors.New(fmt.Sprintf("Property %s have an unsupported type in setJailProperty!\n", propName))
+			}*/
+
+			// panic: reflect: reflect.Value.Set using unaddressable value
+			//val.Set(reflect.ValueOf(propValue).Elem())
+			// ...Because val settability is false :-(
+			fmt.Printf("settability of val: %v\n", val.CanSet())
+
+			// This is OK, using the index to get the real jail object
+			//gJails[i].Config.Allow_mlock = 1
+			
+
+			// TODO : integrate this function
+			setJailConfigUpdated(jail)
+		}
+	}
+
+	return nil
+}
+
+//  We cant use internalName as the value exist only when jail is running
+func setJailConfigUpdated(jail *Jail) error {
+	if len(jail.ConfigPath) == 0 {
+		return errors.New(fmt.Sprintf("No config path for jail %s", jail.Name))
+	}
+
+	for i, j := range gJails {
+		if jail.ConfigPath == j.ConfigPath {
+			gJails[i].ConfigUpdated = true
+			return nil
+		}
+	}
+
+	return errors.New("Jail not found")
+}
+
+func mountProcFs(jail *Jail) error {
+	cmd = fmt.Sprintf("mount -t procfs proc %s/proc", jail.RootPath)
+	_, err := executeCommand(cmd)
+	if err != nil {
+		return errors.New(fmt.Sprintf("Error mounting procfs on %s/proc: %s", jail.RootPath, err.Error()))
+	}
+	
+	return nil
+}
+
+func mountLinProcFs(jail *Jail) error {
+	ldir := fmt.Sprintf("%s/compat/linux/proc", jail.RootPath)
+	_, err := os.Stat(ldir)
+	if os.IsNotExist(err) {
+		errDir := os.MkdirAll(ldir, 0755)
+		if errDir != nil {
+			return errors.New(fmt.Sprintf("Error creating directory %s: %s", ldir, errDir.Error()))
+		}
+	}
+	cmd = fmt.Sprintf("mount -t linprocfs linproc %s", ldir)
+	_, err = executeCommand(cmd)
+	if err != nil {
+		return errors.New(fmt.Sprintf("Error mounting linprocfs on %s: %s", ldir, err.Error()))
+	}
+	
+	return nil
+}
+
+func mountDevFs(jail *Jail) error {
+	cmd = fmt.Sprintf("mount -t devfs dev %s/dev", jail.RootPath)
+	_, err := executeCommand(cmd)
+	if err != nil {
+		return errors.New(fmt.Sprintf("Error mounting devfs on %s/dev: %s", jail.RootPath, err.Error()))
+	}
+	
+	return nil
+}
+
+func mountFdescFs(jail *Jail) error {
+	// FreeBSD <= 9.3 do not support fdescfs
+	if gHostVersion <= 9.3 {
+		fmt.Printf("    FreeBSD <= 9.3 does not support fdescfs, disabling in config\n")
+		jail.Config.Mount_fdescfs = 0
+		// Tag config so it will be synced on disk
+		jail.ConfigUpdated = true
+	
+		// Should we consider this an error?
+		return nil
+	}
+	
+	cmd = fmt.Sprintf("mount -t fdescfs descfs %s/dev/fd", jail.RootPath)
+	_, err := executeCommand(cmd)
+	if err != nil {
+		return errors.New(fmt.Sprintf("Error mounting fdescfs on %s/dev/fd: %s", jail.RootPath, err.Error()))
+	}
+	
+	return nil
+}
 
 func mountAllJailFsFromHost(jail *Jail) error {
 	procfsFound := false
@@ -52,59 +176,107 @@ func mountAllJailFsFromHost(jail *Jail) error {
 
 	// Mount wanted FS
 	if jail.Config.Mount_procfs > 0 && procfsFound == false {
-		cmd = fmt.Sprintf("mount -t procfs proc %s/proc", jail.RootPath)
+		err := mountProcFs(jail)
-		_, err := executeCommand(cmd)
         if err != nil {
-	        return errors.New(fmt.Sprintf("Error mounting procfs on %s/proc: %s", jail.RootPath, err.Error()))
+	        return err
         }   
 	}
+	
 	if jail.Config.Mount_linprocfs > 0 && linProcfsFound == false {
-		ldir := fmt.Sprintf("%s/compat/linux/proc", jail.RootPath)
+		err = mountLinProcFs(jail)
-		_, err := os.Stat(ldir)
-		if os.IsNotExist(err) {
-			errDir := os.MkdirAll(ldir, 0755)
-			if errDir != nil {
-				return errors.New(fmt.Sprintf("Error creating directory %s: %s", ldir, errDir.Error()))
-			}
-		}
-		cmd = fmt.Sprintf("mount -t linprocfs proc %s", ldir)
-		_, err = executeCommand(cmd)
         if err != nil {
-	        return errors.New(fmt.Sprintf("Error mounting linprocfs on %s: %s", ldir, err.Error()))
+	        return err
         }
 	}
+	
 	if jail.Config.Mount_devfs > 0 && devfsFound == false {
-		cmd = fmt.Sprintf("mount -t devfs dev %s/dev", jail.RootPath)
+		err := mountDevFs(jail)
-		_, err := executeCommand(cmd)
+		if err != nil {
-        if err != nil {
+	        return err
-	        return errors.New(fmt.Sprintf("Error mounting devfs on %s/dev: %s", jail.RootPath, err.Error()))
+		}
-        }
 	}
 	if jail.Config.Mount_fdescfs > 0 && fdescfsFound == false {
-		cmd = fmt.Sprintf("mount -t fdescfs descfs %s/dev/fd", jail.RootPath)
+		err := mountFdescFs(jail)
-		_, err := executeCommand(cmd)
+		if err != nil {
-        if err != nil {
+			return err
-	        return errors.New(fmt.Sprintf("Error mounting fdescfs on %s/dev/fd: %s", jail.RootPath, err.Error()))
+		}
-        }
+	}
+
+	
+	// Ces montages doivent-ils etre effectués une fois le jail démarré?
+
+	// FreeBSD <= 9.3 do not support fdescfs
+	//if gHostVersion <= 9.3 && jail.Config.Allow_mount_tmpfs > 0 {
+	if gHostVersion <= 9.3 && jail.Config.Allow_mount_tmpfs > 0 {
+		fmt.Printf("    FreeBSD <= 9.3 does not support tmpfs, disabling in config\n")
+		jail.Config.Allow_mount_tmpfs = 0
+		// Tag config so it will be synced on disk
+		jail.ConfigUpdated = true
+		err = setJailConfigUpdated(jail)
+		if err != nil {
+			fmt.Printf(fmt.Sprintf("Error updating config for jail %s: %s", jail.Name, err.Error()))
+			return err
+		}
+	}
+
+	if gHostVersion < 12 {
+		if jail.Config.Allow_mlock > 0 {
+			jail.Config.Allow_mlock = 0		
+			jail.ConfigUpdated = true
+			/* WIP
+			err = setJailProperty(jail, "Config.Allow_mlock", "0")
+			if err != nil {
+				return err
+			}*/
+		}
+		if jail.Config.Allow_mount_fusefs > 0 {
+		}
+		if jail.Config.Allow_vmm > 0 {
+		}
 	}
 
     return nil 
 }
 
-/*
+
 // TODO 
-func mountJailZfs(jail *Jail) error {
+func prepareJailedZfsDatasets(jail *Jail) error {
 	if jail.Config.Jail_zfs > 0 {
+		// For jail to mount filesystem, enforce_statfs should be 1 or lower (2 is the default)
 		// TODO : Write these changes in jail config file
 		jail.Config.Allow_mount = 1
 		jail.Config.Allow_mount_zfs = 1
+		// TODO : Overload Json Unmarshalling to fix bad typed values, keeping iocage compatibility
+		if jail.Config.Enforce_statfs > "1" {
+			jail.Config.Enforce_statfs = "1"
+		}
 		for _, d := range strings.Split(jail.Config.Jail_zfs_dataset, " ") {
-			
+			// Check if dataset exist, create if necessary
+			cmd := fmt.Sprintf("zfs get -H creation %s/%s", jail.Zpool, d)
+			out, err := executeCommand(cmd)
+			if err != nil {
+				if strings.HasSuffix(out, "dataset does not exist") {
+					cmd = fmt.Sprintf("zfs create -o compression=lz4 -o mountpoint=none %s/%s", jail.Zpool, d)
+					_, err = executeCommand(cmd)
+					if err != nil {
+						return errors.New(fmt.Sprintf("Error creating dataset %s/%s: %s", jail.Zpool, d, err.Error()))
+					}
+				} else {
+					return errors.New(fmt.Sprintf("Error getting zfs dataset %s: %s", d, err.Error()))
+				}
+			}
+
+			cmd = fmt.Sprintf("zfs set jailed=on %s/%s", jail.Zpool, d)
+			out, err = executeCommand(cmd)
+			if err != nil {
+				return errors.New(fmt.Sprintf("Error executing \"zfs set jailed=on %s/%s\": %s", jail.Zpool, d, err.Error()))
+			}
+			// TODO : Execute "zfs jail $jailname $dataset" when jail will be up
 		}
 	}
 	return nil
 }
-*/
+
 
 
 /*
@@ -139,9 +311,10 @@ func StartJail(args []string) {
 	for _, j := range args {
 		fmt.Printf("> Starting jail %s\n", j)
 
-		for _, rj := range gJails {
+		for i, rj := range gJails {
 			if rj.Name == j {
-				cj = &rj
+				// Get jail reference, not a copy of it; So we can modify attributes
+				cj = &gJails[i]
 				break
 			}
 		}
@@ -163,6 +336,16 @@ func StartJail(args []string) {
 			fmt.Printf("  > Mount special filesystems: OK\n")
 		}
 
+		if cj.Config.Jail_zfs > 0 {
+			fmt.Printf("  > Prepare ZFS Datasets:\n")
+			err := prepareJailedZfsDatasets(cj)
+			if err != nil {
+				fmt.Printf("ERROR: %s\n", err.Error())
+			} else {
+				fmt.Printf("  > Prepare ZFS Datasets: OK\n")
+			}
+		}
+
 
 /*
 		out, err := executeCommand(fmt.Sprintf("rctl jail:%s", cj.InternalName))