compileopts: add 'retries' flag to allow setting the number of times to retry locating the MSD volume when flashing

Signed-off-by: deadprogram <ron@hybridgroup.com>

compileopts/options.go

@@ -51,6 +51,7 @@ type Options struct {
 	PrintJSON       bool
 	Monitor         bool
 	BaudRate        int
+	Retries         int
 }
 
 // Verify performs a validation on the given options, raising an error if options are not valid.

main.go

@@ -928,8 +928,6 @@ func touchSerialPortAt1200bps(port string) (err error) {
 	return fmt.Errorf("opening port: %s", err)
 }
 
-const maxMSDRetries = 10
-
 func flashUF2UsingMSD(volume, tmppath string, options *compileopts.Options) error {
 	// find standard UF2 info path
 	var infoPath string
@@ -951,7 +949,7 @@ func flashUF2UsingMSD(volume, tmppath string, options *compileopts.Options) erro
 		infoPath = path + "/INFO_UF2.TXT"
 	}
 
-	d, err := locateDevice(volume, infoPath)
+	d, err := locateDevice(volume, infoPath, options.Retries)
 	if err != nil {
 		return err
 	}
@@ -980,7 +978,7 @@ func flashHexUsingMSD(volume, tmppath string, options *compileopts.Options) erro
 		destPath = path + "/"
 	}
 
-	d, err := locateDevice(volume, destPath)
+	d, err := locateDevice(volume, destPath, options.Retries)
 	if err != nil {
 		return err
 	}
@@ -988,10 +986,10 @@ func flashHexUsingMSD(volume, tmppath string, options *compileopts.Options) erro
 	return moveFile(tmppath, d+"/flash.hex")
 }
 
-func locateDevice(volume, path string) (string, error) {
+func locateDevice(volume, path string, maxRetries int) (string, error) {
 	var d []string
 	var err error
-	for i := 0; i < maxMSDRetries; i++ {
+	for i := 0; i < maxRetries; i++ {
 		d, err = filepath.Glob(path)
 		if err != nil {
 			return "", err
@@ -1398,6 +1396,7 @@ func main() {
 	ocdCommandsString := flag.String("ocd-commands", "", "OpenOCD commands, overriding target spec (can specify multiple separated by commas)")
 	ocdOutput := flag.Bool("ocd-output", false, "print OCD daemon output during debug")
 	port := flag.String("port", "", "flash port (can specify multiple candidates separated by commas)")
+	maxRetries := flag.Int("retries", 10, "the maximum number of times to retry locating the MSD volume to be used for flashing")
 	programmer := flag.String("programmer", "", "which hardware programmer to use")
 	ldflags := flag.String("ldflags", "", "Go link tool compatible ldflags")
 	llvmFeatures := flag.String("llvm-features", "", "comma separated LLVM features to enable")
@@ -1494,6 +1493,7 @@ func main() {
 		PrintJSON:       flagJSON,
 		Monitor:         *monitor,
 		BaudRate:        *baudrate,
+		Retries:         *maxRetries,
 	}
 	if *printCommands {
 		options.PrintCommands = printCommand