bugfix: serial enumerator failures in some rare circumstances (#830)

* Use io.Discard instead of custom nullWriter

* Renamed and slightly refactored port enumerators

* Useless code beautify

* Updated go.bug.st/serial lib to 1.6.0

* Empty port list if the enumerator fails

* Synchronize multiple serial-port update request

* Upgraded go-serial to 1.6.1

* Update serial.go

Co-authored-by: Umberto Baldi <[email protected]>

---------

Co-authored-by: Umberto Baldi <[email protected]>

Author: cmaglie

.licenses/arduino-create-agent/go/go.bug.st/serial.dep.yml

@@ -1,6 +1,6 @@
 ---
 name: go.bug.st/serial
-version: v1.4.1
+version: v1.6.1
 type: go
 summary: Package serial is a cross-platform serial library for the go language.
 homepage: https://pkg.go.dev/go.bug.st/serial
@@ -9,7 +9,7 @@ licenses:
 - sources: LICENSE
   text: |2+
 
-    Copyright (c) 2014-2021, Cristian Maglie.
+    Copyright (c) 2014-2023, Cristian Maglie.
     All rights reserved.
 
     Redistribution and use in source and binary forms, with or without

.licenses/arduino-create-agent/go/go.bug.st/serial/enumerator.dep.yml

@@ -1,16 +1,16 @@
 ---
 name: go.bug.st/serial/enumerator
-version: v1.4.1
+version: v1.6.1
 type: go
 summary: Package enumerator is a golang cross-platform library for USB serial port
   discovery.
 homepage: https://pkg.go.dev/go.bug.st/serial/enumerator
 license: bsd-3-clause
 licenses:
-- sources: serial@v1.4.1/LICENSE
+- sources: serial@v1.6.1/LICENSE
   text: |2+
 
-    Copyright (c) 2014-2021, Cristian Maglie.
+    Copyright (c) 2014-2023, Cristian Maglie.
     All rights reserved.
 
     Redistribution and use in source and binary forms, with or without
@@ -42,7 +42,7 @@ licenses:
     ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     POSSIBILITY OF SUCH DAMAGE.
 
-- sources: serial@v1.4.1/README.md
+- sources: serial@v1.6.1/README.md
   text: |-
     The software is release under a [BSD 3-clause license]
 

.licenses/arduino-create-agent/go/go.bug.st/serial/unixutils.dep.yml

@@ -1,15 +1,15 @@
 ---
 name: go.bug.st/serial/unixutils
-version: v1.4.1
+version: v1.6.1
 type: go
 summary: 
 homepage: https://pkg.go.dev/go.bug.st/serial/unixutils
 license: bsd-3-clause
 licenses:
-- sources: serial@v1.4.1/LICENSE
+- sources: serial@v1.6.1/LICENSE
   text: |2+
 
-    Copyright (c) 2014-2021, Cristian Maglie.
+    Copyright (c) 2014-2023, Cristian Maglie.
     All rights reserved.
 
     Redistribution and use in source and binary forms, with or without
@@ -41,7 +41,7 @@ licenses:
     ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     POSSIBILITY OF SUCH DAMAGE.
 
-- sources: serial@v1.4.1/README.md
+- sources: serial@v1.6.1/README.md
   text: |-
     The software is release under a [BSD 3-clause license]
 

discovery.go

@@ -42,10 +42,10 @@ const timeoutConst = 2
 // SavedNetworkPorts contains the ports which we know are already connected
 var SavedNetworkPorts []OsSerialPort
 
-// GetNetworkList returns a list of Network Ports
+// enumerateNetworkPorts returns a list of Network Ports
 // The research of network ports is articulated in two phases. First we add new ports coming from
 // the bonjour module, then we prune the boards who don't respond to a ping
-func GetNetworkList() ([]OsSerialPort, error) {
+func enumerateNetworkPorts() ([]OsSerialPort, error) {
 	newPorts, err := getPorts()
 	if err != nil {
 		return nil, err

go.mod

@@ -22,7 +22,7 @@ require (
 	github.com/stretchr/testify v1.8.4
 	github.com/xrash/smetrics v0.0.0-20170218160415-a3153f7040e9
 	go.bug.st/downloader/v2 v2.1.1
-	go.bug.st/serial v1.4.1
+	go.bug.st/serial v1.6.1
 	goa.design/goa/v3 v3.12.4
 	golang.org/x/crypto v0.12.0
 	golang.org/x/sys v0.11.0

go.sum

@@ -165,8 +165,8 @@ github.com/xrash/smetrics v0.0.0-20170218160415-a3153f7040e9 h1:w8V9v0qVympSF6Gj
 github.com/xrash/smetrics v0.0.0-20170218160415-a3153f7040e9/go.mod h1:N3UwUGtsrSj3ccvlPHLoLsHnpR27oXr4ZE984MbSER8=
 go.bug.st/downloader/v2 v2.1.1 h1:nyqbUizo3E2IxCCm4YFac4FtSqqFpqWP+Aae5GCMuw4=
 go.bug.st/downloader/v2 v2.1.1/go.mod h1:VZW2V1iGKV8rJL2ZEGIDzzBeKowYv34AedJz13RzVII=
-go.bug.st/serial v1.4.1 h1:AwYUNixVf90XymNeJaUkMrPp+GZQe3RMFQmpVdHIUK8=
-go.bug.st/serial v1.4.1/go.mod h1:z8CesKorE90Qr/oRSJiEuvzYRKol9r/anJZEb5kt304=
+go.bug.st/serial v1.6.1 h1:VSSWmUxlj1T/YlRo2J104Zv3wJFrjHIl/T3NeruWAHY=
+go.bug.st/serial v1.6.1/go.mod h1:UABfsluHAiaNI+La2iESysd9Vetq7VRdpxvjx7CmmOE=
 goa.design/goa/v3 v3.12.4 h1:g3G8yHLk+jyUDNRL2sNg+ZcoQ62zY83rpgagAQ5VmTA=
 goa.design/goa/v3 v3.12.4/go.mod h1:h1vjyGQ+rqWK+VvnqN8oLcpqaHrKIyuY1Vx+jhKodpg=
 golang.org/x/arch v0.0.0-20210923205945-b76863e36670 h1:18EFjUmQOcUvxNYSkA6jO9VAiXCnxFY6NyDX0bHDmkU=

main.go

@@ -22,6 +22,7 @@ import (
 	_ "embed"
 	"encoding/json"
 	"flag"
+	"io"
 	"os"
 	"os/exec"
 	"runtime"
@@ -99,10 +100,6 @@ var (
 	Systray systray.Systray
 )
 
-type nullWriter int
-
-func (nullWriter) Write([]byte) (int, error) { return 0, nil }
-
 type logWriter struct{}
 
 func (u *logWriter) Write(p []byte) (n int, err error) {
@@ -310,7 +307,7 @@ func loop() {
 	}
 
 	// list serial ports
-	portList, _ := GetList(false)
+	portList, _ := enumerateSerialPorts()
 	log.Println("Your serial ports:")
 	if len(portList) == 0 {
 		log.Println("\tThere are no serial ports to list.")
@@ -322,7 +319,7 @@ func loop() {
 
 	if !*verbose {
 		log.Println("You can enter verbose mode to see all logging by starting with the -v command line switch.")
-		log.SetOutput(new(nullWriter)) //route all logging to nullwriter
+		log.SetOutput(io.Discard)
 	}
 
 	// save crashreport to file

serial.go

@@ -71,11 +71,11 @@ type SpPortItem struct {
 	ProductID       string
 }
 
-// SerialPorts contains the ports attached to the machine
-var SerialPorts SpPortList
+// serialPorts contains the ports attached to the machine
+var serialPorts SpPortList
 
-// NetworkPorts contains the ports on the network
-var NetworkPorts SpPortList
+// networkPorts contains the ports on the network
+var networkPorts SpPortList
 
 var sh = serialhub{
 	//write:   	make(chan *serport, chan []byte),
@@ -130,13 +130,13 @@ func spList(network bool) {
 	var ls []byte
 	var err error
 	if network {
-		NetworkPorts.Mu.Lock()
-		ls, err = json.MarshalIndent(&NetworkPorts, "", "\t")
-		NetworkPorts.Mu.Unlock()
+		networkPorts.Mu.Lock()
+		ls, err = json.MarshalIndent(&networkPorts, "", "\t")
+		networkPorts.Mu.Unlock()
 	} else {
-		SerialPorts.Mu.Lock()
-		ls, err = json.MarshalIndent(&SerialPorts, "", "\t")
-		SerialPorts.Mu.Unlock()
+		serialPorts.Mu.Lock()
+		ls, err = json.MarshalIndent(&serialPorts, "", "\t")
+		serialPorts.Mu.Unlock()
 	}
 	if err != nil {
 		//log.Println(err)
@@ -149,81 +149,73 @@ func spList(network bool) {
 
 // discoverLoop periodically update the list of ports found
 func discoverLoop() {
-	SerialPorts.Mu.Lock()
-	SerialPorts.Network = false
-	SerialPorts.Ports = make([]SpPortItem, 0)
-	SerialPorts.Mu.Unlock()
-	NetworkPorts.Mu.Lock()
-	NetworkPorts.Network = true
-	NetworkPorts.Ports = make([]SpPortItem, 0)
-	NetworkPorts.Mu.Unlock()
+	serialPorts.Mu.Lock()
+	serialPorts.Network = false
+	serialPorts.Ports = make([]SpPortItem, 0)
+	serialPorts.Mu.Unlock()
+	networkPorts.Mu.Lock()
+	networkPorts.Network = true
+	networkPorts.Ports = make([]SpPortItem, 0)
+	networkPorts.Mu.Unlock()
 
 	go func() {
 		for {
 			if !upload.Busy {
-				spListDual(false)
+				updateSerialPortList()
 			}
 			time.Sleep(2 * time.Second)
 		}
 	}()
 	go func() {
 		for {
-			spListDual(true)
+			updateNetworkPortList()
 			time.Sleep(2 * time.Second)
 		}
 	}()
 }
 
-func spListDual(network bool) {
+var serialEnumeratorLock sync.Mutex
 
-	// call our os specific implementation of getting the serial list
-	list, err := GetList(network)
+func updateSerialPortList() {
+	if !serialEnumeratorLock.TryLock() {
+		return
+	}
+	defer serialEnumeratorLock.Unlock()
+	ports, err := enumerateSerialPorts()
+	if err != nil {
+		// TODO: report error?
 
-	//log.Println(list)
-	//log.Println(err)
+		// Empty port list if they can not be detected
+		ports = []OsSerialPort{}
+	}
+	list := spListDual(ports)
+	serialPorts.Mu.Lock()
+	serialPorts.Ports = list
+	serialPorts.Mu.Unlock()
+}
 
+func updateNetworkPortList() {
+	ports, err := enumerateNetworkPorts()
 	if err != nil {
-		// avoid reporting dummy data if an error occurred
-		return
-	}
+		// TODO: report error?
 
-	// do a quick loop to see if any of our open ports
-	// did not end up in the list port list. this can
-	// happen on windows in a fallback scenario where an
-	// open port can't be identified because it is locked,
-	// so just solve that by manually inserting
-	// if network {
-	// 	for port := range sh.ports {
-
-	// 		isFound := false
-	// 		for _, item := range list {
-	// 			if strings.ToLower(port.portConf.Name) == strings.ToLower(item.Name) {
-	// 				isFound = true
-	// 			}
-	// 		}
-
-	// 		if !isFound {
-	// 			// artificially push to front of port list
-	// 			log.Println(fmt.Sprintf("Did not find an open port in the serial port list. We are going to artificially push it onto the list. port:%v", port.portConf.Name))
-	// 			var ossp OsSerialPort
-	// 			ossp.Name = port.portConf.Name
-	// 			ossp.FriendlyName = port.portConf.Name
-	// 			list = append([]OsSerialPort{ossp}, list...)
-	// 		}
-	// 	}
-	// }
+		// Empty port list if they can not be detected
+		ports = []OsSerialPort{}
+	}
+	list := spListDual(ports)
+	networkPorts.Mu.Lock()
+	networkPorts.Ports = list
+	networkPorts.Mu.Unlock()
+}
 
+func spListDual(list []OsSerialPort) []SpPortItem {
 	// we have a full clean list of ports now. iterate thru them
 	// to append the open/close state, baud rates, etc to make
 	// a super clean nice list to send back to browser
-	n := len(list)
-	spl := make([]SpPortItem, n)
-
-	ctr := 0
+	spl := []SpPortItem{}
 
 	for _, item := range list {
-
-		spl[ctr] = SpPortItem{
+		port := SpPortItem{
 			Name:            item.Name,
 			SerialNumber:    item.ISerial,
 			DeviceClass:     item.DeviceClass,
@@ -238,26 +230,15 @@ func spListDual(network bool) {
 		}
 
 		// figure out if port is open
-		myport, isFound := findPortByName(item.Name)
-
-		if isFound {
-			// we found our port
-			spl[ctr].IsOpen = true
-			spl[ctr].Baud = myport.portConf.Baud
-			spl[ctr].BufferAlgorithm = myport.BufferType
+		if myport, isFound := findPortByName(item.Name); isFound {
+			// and update data with the open port parameters
+			port.IsOpen = true
+			port.Baud = myport.portConf.Baud
+			port.BufferAlgorithm = myport.BufferType
 		}
-		ctr++
-	}
-
-	if network {
-		NetworkPorts.Mu.Lock()
-		NetworkPorts.Ports = spl
-		NetworkPorts.Mu.Unlock()
-	} else {
-		SerialPorts.Mu.Lock()
-		SerialPorts.Ports = spl
-		SerialPorts.Mu.Unlock()
+		spl = append(spl, port)
 	}
+	return spl
 }
 
 func spErr(err string) {

seriallist.go

@@ -38,14 +38,8 @@ type OsSerialPort struct {
 	NetworkPort  bool
 }
 
-// GetList will return the OS serial port
-func GetList(network bool) ([]OsSerialPort, error) {
-
-	if network {
-		netportList, err := GetNetworkList()
-		return netportList, err
-	}
-
+// enumerateSerialPorts will return the OS serial port
+func enumerateSerialPorts() ([]OsSerialPort, error) {
 	// will timeout in 2 seconds
 	arrPorts := []OsSerialPort{}
 	ports, err := enumerator.GetDetailedPortsList()