Make the serial communication work

This commit is contained in:
Aaron Fischer 2016-09-28 20:56:31 +02:00
parent 67462dcf04
commit ad792a9dcc

View file

@ -1,36 +1,44 @@
package main package main
// Create a new virtual serial device:
// socat PTY,link=/dev/ttyS10 PTY,link=/dev/ttyS11
import ( import (
"log" "log"
"os" "os"
"path" "path"
"errors"
"github.com/fsnotify/fsnotify" "github.com/fsnotify/fsnotify"
"github.com/tarm/serial"
"github.com/mkideal/cli" "github.com/mkideal/cli"
"github.com/tarm/serial"
) )
// TODO: Make the error code optional (as a parameter) func stop(exitCode int) {
func stop() {
log.Println("Have a nice day.") log.Println("Have a nice day.")
os.Exit(0) os.Exit(exitCode)
} }
func waitAndExecuteCommandsFromDevice(device string) { type message struct {
config := &serial.Config{Name: device, Baud: 115200} msgType byte
serial, err := serial.OpenPort(config) data []byte
}
if err != nil { const (
log.Fatal(err) MSG_TYPE_ANSWER_OK = 0x01
MSG_TYPE_ANSWER_NOOK = 0x02
MSG_TYPE_AGENTID = 0x03
MSG_TYPE_CONFIG = 0x04
)
func decodeByteString(bytes []byte, num int) (msg message, err error) {
if bytes[0] == 0x3c && bytes[1] == 0x3e &&
bytes[num-1] == 0x0A && bytes[num-2] == 0x0D {
return message{msgType: bytes[2], data: bytes[3:num-2]}, nil
} }
log.Printf("Open the connection to the n3rdpad over %s", device) return message{msgType: 0x00, data: make([]byte, 1)}, errors.New("Can't decode the byte array.")
}
// Read from serial func waitAndExecuteCommandsFromDevice(serial *serial.Port) {
buffer := make([]byte, 128) buffer := make([]byte, 40)
for { for {
num, err := serial.Read(buffer) num, err := serial.Read(buffer)
@ -38,12 +46,21 @@ func waitAndExecuteCommandsFromDevice(device string) {
log.Fatal(err) log.Fatal(err)
} }
// TODO: Do something with the incomind commands input, err := decodeByteString(buffer, num)
log.Printf("%q", buffer[:num]) if err != nil {
log.Fatal(err)
} else {
switch (input.msgType) {
case MSG_TYPE_AGENTID:
log.Printf("Key pressed: %d", input.data[0])
default:
log.Fatal("Can't recognize the message type.")
}
}
} }
} }
func watchForConfigChanges(configFile string) { func watchForConfigChanges(configFile string, serial *serial.Port) {
watcher, err := fsnotify.NewWatcher() watcher, err := fsnotify.NewWatcher()
if err != nil { if err != nil {
log.Fatal(err) log.Fatal(err)
@ -72,7 +89,7 @@ func watchForConfigChanges(configFile string) {
} }
} }
// Some editors have a feature calles "swap save" (like vim), which // Some editors have a feature called "swap save" (like vim), which
// will trigger a simple WRITE event, instead it wil trigger RENAME // will trigger a simple WRITE event, instead it wil trigger RENAME
// -> CHMOD -> REMOVE in that order. So we lost track of the file. // -> CHMOD -> REMOVE in that order. So we lost track of the file.
// To prevent this, we add the file again, if it exist after a // To prevent this, we add the file again, if it exist after a
@ -82,13 +99,13 @@ func watchForConfigChanges(configFile string) {
watcher.Add(event.Name) watcher.Add(event.Name)
} else { } else {
log.Fatal("Lost the configuration file. We stop now.") log.Fatal("Lost the configuration file. We stop now.")
stop() stop(1)
} }
} }
case err := <-watcher.Errors: case err := <-watcher.Errors:
log.Println("We have the following problem with the configuration file: ", err) log.Println("We have the following problem with the configuration file: ", err)
log.Println("Try the fix this problem by yourself and restart the agent.") log.Println("Try the fix this problem by yourself and restart the agent.")
stop() stop(2)
} }
} }
}() }()
@ -117,16 +134,28 @@ func main() {
} }
if args.Device == "" { if args.Device == "" {
log.Fatal("You need to specify the serial device with the --device parameter.") log.Fatal("You need to specify the serial device with the --device parameter.")
stop(); stop(3)
} }
if !args.Help { if !args.Help {
// Start up the application // Start up the application
log.Println("Using the configuration file", configFile) log.Println("Using the configuration file", configFile)
go watchForConfigChanges(configFile)
waitAndExecuteCommandsFromDevice(args.Device)
stop() // Open the serial connection
config := &serial.Config{Name: args.Device, Baud: 115200}
serial, err := serial.OpenPort(config)
if err != nil {
log.Fatal(err)
return nil
}
log.Printf("Open the connection to the n3rdpad over %s", args.Device)
go watchForConfigChanges(configFile, serial)
waitAndExecuteCommandsFromDevice(serial)
stop(0)
} }
return nil return nil