Split up functions into seperate files

Makefile

@@ -83,7 +83,7 @@ clean: # @HELP removes built binaries and temporary files
 clean: bin-clean
 
 bin-clean:
-	rm -rf .go bin
+	rm -rf .go bin *.exe
 
 help: # @HELP prints this message
 help:

apg.go

@@ -1,17 +1,14 @@
 package main
 
 import (
-	"crypto/rand"
 	"flag"
 	"fmt"
-	"math/big"
 	"os"
-	"regexp"
 )
 
 // Constants
 const DefaultPwLenght int = 20
-const VersionString string = "0.2.3"
+const VersionString string = "0.2.4"
 const PwLowerCharsHuman string = "abcdefghjkmnpqrstuvwxyz"
 const PwUpperCharsHuman string = "ABCDEFGHJKMNPQRSTUVWXYZ"
 const PwLowerChars string = "abcdefghijklmnopqrstuvwxyz"
@@ -32,6 +29,7 @@ type cliOpts struct {
 	useSpecial    bool
 	humanReadable bool
 	excludeChars  string
+	newStyleModes string
 	showHelp      bool
 	showVersion   bool
 }
@@ -56,6 +54,8 @@ func init() {
 
 	// String flags
 	flag.StringVar(&config.excludeChars, "E", "", "Exclude list of characters from generated password")
+	flag.StringVar(&config.newStyleModes, "M", "",
+		"New style password parameters (higher priority than single parameters)")
 
 	flag.Parse()
 	if config.showVersion {
@@ -66,21 +66,8 @@ func init() {
 
 // Main function that generated the passwords and returns them
 func main() {
-	pwLength := config.minPassLen
+	parseParams()
-	if pwLength < config.minPassLen {
+	pwLength := getPwLengthFromParams()
-		pwLength = config.minPassLen
-	}
-	if pwLength > config.maxPassLen {
-		pwLength = config.maxPassLen
-	}
-	if config.useComplex {
-		config.useUpperCase = true
-		config.useLowerCase = true
-		config.useSpecial = true
-		config.useNumber = true
-		config.humanReadable = false
-	}
-
 	charRange := getCharRange()
 
 	for i := 1; i <= config.numOfPass; i++ {
@@ -92,80 +79,3 @@ func main() {
 		fmt.Println(pwString)
 	}
 }
-
-// Provide the range of available characters based on provided parameters
-func getCharRange() string {
-	pwUpperChars := PwUpperChars
-	pwLowerChars := PwLowerChars
-	pwNumbers := PwNumbers
-	pwSpecialChars := PwSpecialChars
-	if config.humanReadable {
-		pwUpperChars = PwUpperCharsHuman
-		pwLowerChars = PwLowerCharsHuman
-		pwNumbers = PwNumbersHuman
-		pwSpecialChars = PwSpecialCharsHuman
-	}
-
-	var charRange string
-	if config.useLowerCase {
-		charRange = charRange + pwLowerChars
-	}
-	if config.useUpperCase {
-		charRange = charRange + pwUpperChars
-	}
-	if config.useNumber {
-		charRange = charRange + pwNumbers
-	}
-	if config.useSpecial {
-		charRange = charRange + pwSpecialChars
-	}
-	if config.excludeChars != "" {
-		regExp := regexp.MustCompile("[" + config.excludeChars + "]")
-		charRange = regExp.ReplaceAllLiteralString(charRange, "")
-	}
-
-	return charRange
-}
-
-// Generate random characters based on given character range
-// and password length
-func getRandChar(charRange *string, pwLength int) (string, error) {
-	if pwLength <= 0 {
-		err := fmt.Errorf("provided pwLength value is <= 0: %v", pwLength)
-		return "", err
-	}
-	availCharsLength := len(*charRange)
-	charSlice := []byte(*charRange)
-	returnString := make([]byte, pwLength)
-	for i := 0; i < pwLength; i++ {
-		randNum, err := getRandNum(availCharsLength)
-		if err != nil {
-			return "", err
-		}
-		returnString[i] = charSlice[randNum]
-	}
-	return string(returnString), nil
-}
-
-// Generate a random number with given maximum value
-func getRandNum(maxNum int) (int, error) {
-	if maxNum <= 0 {
-		err := fmt.Errorf("provided maxNum is <= 0: %v", maxNum)
-		return 0, err
-	}
-	maxNumBigInt := big.NewInt(int64(maxNum))
-	if !maxNumBigInt.IsUint64() {
-		err := fmt.Errorf("big.NewInt() generation returned negative value: %v", maxNumBigInt)
-		return 0, err
-	}
-	randNum64, err := rand.Int(rand.Reader, maxNumBigInt)
-	if err != nil {
-		return 0, err
-	}
-	randNum := int(randNum64.Int64())
-	if randNum < 0 {
-		err := fmt.Errorf("generated random number does not fit as int64: %v", randNum64)
-		return 0, err
-	}
-	return randNum, nil
-}

chars.go

@@ -0,0 +1,37 @@
+package main
+
+import "regexp"
+
+// Provide the range of available characters based on provided parameters
+func getCharRange() string {
+	pwUpperChars := PwUpperChars
+	pwLowerChars := PwLowerChars
+	pwNumbers := PwNumbers
+	pwSpecialChars := PwSpecialChars
+	if config.humanReadable {
+		pwUpperChars = PwUpperCharsHuman
+		pwLowerChars = PwLowerCharsHuman
+		pwNumbers = PwNumbersHuman
+		pwSpecialChars = PwSpecialCharsHuman
+	}
+
+	var charRange string
+	if config.useLowerCase {
+		charRange = charRange + pwLowerChars
+	}
+	if config.useUpperCase {
+		charRange = charRange + pwUpperChars
+	}
+	if config.useNumber {
+		charRange = charRange + pwNumbers
+	}
+	if config.useSpecial {
+		charRange = charRange + pwSpecialChars
+	}
+	if config.excludeChars != "" {
+		regExp := regexp.MustCompile("[" + config.excludeChars + "]")
+		charRange = regExp.ReplaceAllLiteralString(charRange, "")
+	}
+
+	return charRange
+}

params.go

@@ -0,0 +1,87 @@
+package main
+
+import (
+	"fmt"
+	"os"
+)
+
+// Parse the new style parameters
+func parseNewStyleParams() {
+	for _, curParam := range config.newStyleModes {
+		switch curParam {
+		case 'S':
+			config.useSpecial = true
+			break
+		case 's':
+			config.useSpecial = false
+			break
+		case 'N':
+			config.useNumber = true
+			break
+		case 'n':
+			config.useNumber = false
+			break
+		case 'L':
+			config.useLowerCase = true
+			break
+		case 'l':
+			config.useLowerCase = false
+			break
+		case 'U':
+			config.useUpperCase = true
+			break
+		case 'u':
+			config.useUpperCase = false
+			break
+		case 'H':
+			config.humanReadable = true
+			break
+		case 'h':
+			config.humanReadable = false
+			break
+		// APG compatbilitly
+		case 'C':
+			config.useUpperCase = true
+			break
+		case 'c':
+			config.useUpperCase = false
+			break
+		default:
+			fmt.Printf("Unknown password style parameter: %q\n", string(curParam))
+			os.Exit(1)
+		}
+	}
+}
+
+func getPwLengthFromParams() int {
+	pwLength := config.minPassLen
+	if pwLength < config.minPassLen {
+		pwLength = config.minPassLen
+	}
+	if pwLength > config.maxPassLen {
+		pwLength = config.maxPassLen
+	}
+
+	return pwLength
+}
+
+func parseParams() {
+	if config.useComplex {
+		config.useUpperCase = true
+		config.useLowerCase = true
+		config.useSpecial = true
+		config.useNumber = true
+		config.humanReadable = false
+	}
+	if config.newStyleModes != "" {
+		parseNewStyleParams()
+	}
+
+	if config.useUpperCase == false &&
+		config.useLowerCase == false &&
+		config.useNumber == false &&
+		config.useSpecial == false {
+		fmt.Printf("No password mode set. Cannot generate password from empty character set.")
+		os.Exit(1)
+	}
+}

rand.go

@@ -0,0 +1,50 @@
+package main
+
+import (
+	"crypto/rand"
+	"fmt"
+	"math/big"
+)
+
+// Generate random characters based on given character range
+// and password length
+func getRandChar(charRange *string, pwLength int) (string, error) {
+	if pwLength <= 0 {
+		err := fmt.Errorf("provided pwLength value is <= 0: %v", pwLength)
+		return "", err
+	}
+	availCharsLength := len(*charRange)
+	charSlice := []byte(*charRange)
+	returnString := make([]byte, pwLength)
+	for i := 0; i < pwLength; i++ {
+		randNum, err := getRandNum(availCharsLength)
+		if err != nil {
+			return "", err
+		}
+		returnString[i] = charSlice[randNum]
+	}
+	return string(returnString), nil
+}
+
+// Generate a random number with given maximum value
+func getRandNum(maxNum int) (int, error) {
+	if maxNum <= 0 {
+		err := fmt.Errorf("provided maxNum is <= 0: %v", maxNum)
+		return 0, err
+	}
+	maxNumBigInt := big.NewInt(int64(maxNum))
+	if !maxNumBigInt.IsUint64() {
+		err := fmt.Errorf("big.NewInt() generation returned negative value: %v", maxNumBigInt)
+		return 0, err
+	}
+	randNum64, err := rand.Int(rand.Reader, maxNumBigInt)
+	if err != nil {
+		return 0, err
+	}
+	randNum := int(randNum64.Int64())
+	if randNum < 0 {
+		err := fmt.Errorf("generated random number does not fit as int64: %v", randNum64)
+		return 0, err
+	}
+	return randNum, nil
+}