Fix init if devices directory does not exist/is empty

core/configParser.go

@@ -51,13 +51,17 @@ func ParseConfig(valuesRequested [][2]string, missingValueError string) []string
 }
 
 // GenDeviceIDList returns a pointer to a slice of all registered device IDs.
-// Requires: errorOnFail (set to true to throw an error if the device ID list cannot be generated)
+// Requires: errorOnFail (set to true to throw an error if the devices directory cannot be read/does not exist)
 func GenDeviceIDList(errorOnFail bool) *[]fs.DirEntry {
 	// create a slice of all registered devices
 	deviceIDList, err := os.ReadDir(ConfigDir + PathSeparator + "devices")
-	if err != nil && errorOnFail {
-		fmt.Println(AnsiError+"Failed to read the devices directory:", err.Error()+AnsiReset)
-		os.Exit(101)
+	if err != nil {
+		if errorOnFail {
+			fmt.Println(AnsiError+"Failed to read the devices directory:", err.Error()+AnsiReset)
+			os.Exit(101)
+		} else {
+			return nil // a nil return value indicates that the devices directory could not be read/does not exist
+		}
 	}
 	return &deviceIDList
 }

core/init.go

@@ -53,7 +53,7 @@ func GpgKeyGen() string {
 }
 
 // DirInit creates the libmutton directories.
-// Returns: oldDeviceID (from before the directory reset).
+// Returns: oldDeviceID (from before the directory reset; will be sync.FSMisc if there is no pre-existing ID).
 func DirInit(preserveOldConfigDir bool) string {
 	// create EntryRoot
 	err := os.MkdirAll(EntryRoot, 0700)
@@ -63,7 +63,13 @@ func DirInit(preserveOldConfigDir bool) string {
 	}
 
 	// get old device ID before its potential removal
-	oldDeviceID := (*GenDeviceIDList(false))[0].Name() // errorOnFail set to false to ignore error if device ID directory does not exist (error non-critical for this function)
+	oldDeviceIDList := GenDeviceIDList(false) // errorOnFail is false so that nil is received when the devices directory does not exist
+	var oldDeviceID string
+	if oldDeviceIDList != nil && len(*oldDeviceIDList) > 0 { // ensure not derferencing nil, which occurs when the devices directory does not exist
+		oldDeviceID = (*oldDeviceIDList)[0].Name()
+	} else {
+		oldDeviceID = "\u259f" // sync.FSMisc cannot be used directly due to import cycle; indicates to server that no device ID is being replaced
+	}
 
 	// remove existing config directory (if it exists and not in append mode)
 	if !preserveOldConfigDir {

core/utilitiesMisc.go

@@ -20,9 +20,8 @@ func TargetIsFile(targetLocation string, errorOnFail bool, failCondition uint8)
 		if errorOnFail {
 			fmt.Println(AnsiError + "Failed to access \"" + targetLocation + "\" - Ensure it exists and has the correct permissions" + AnsiReset)
 			os.Exit(105)
-		} else {
-			return false, false
 		}
+		return false, false
 	}
 	if targetInfo.IsDir() {
 		if errorOnFail && failCondition == 2 {