// Copyright Terence J. Boldt (c)2020-2022 // Use of this source code is governed by an MIT // license that can be found in the LICENSE file. // This file contains the handler for executing Linux and internal // commands package handlers import ( "errors" "fmt" "io" "os" "os/exec" "strings" ) var forceLowercase = false // ExecCommand handles requests for the Apple II executing Linux commands func ExecCommand() { workingDirectory, err := os.Getwd() if err != nil { workingDirectory = "/home" comm.WriteString("Failed to get current working directory, setting to /home\r") } fmt.Printf("Reading command to execute...\n") linuxCommand, err := comm.ReadString() if forceLowercase { linuxCommand = strings.ToLower(linuxCommand) } linuxCommand = strings.Trim(linuxCommand, " ") if linuxCommand == "" { linuxCommand = "a2help" } fmt.Printf("Command to run: %s\n", linuxCommand) if strings.HasPrefix(linuxCommand, "cd ") { workingDirectory = strings.Replace(linuxCommand, "cd ", "", 1) err = os.Chdir(workingDirectory) if err != nil { comm.WriteString("Failed to set working directory\r") return } comm.WriteString("Working directory set\r") return } if linuxCommand == "a2help" { a2help() return } if linuxCommand == "a2lower" { a2lower(false) return } if linuxCommand == "A2LOWER" { a2lower(true) return } if linuxCommand == "a2wifi" { a2wifi() return } if linuxCommand == "a2prompt" { prompt := fmt.Sprintf("A2IO:%s ", workingDirectory) comm.WriteString(prompt) return } if linuxCommand == "a2wifi list" { linuxCommand = a2wifiList() } if strings.HasPrefix(linuxCommand, "a2wifi select") { linuxCommand, err = a2wifiSelect(linuxCommand) } if err == nil { execCommand(linuxCommand, workingDirectory) } } func execCommand(linuxCommand string, workingDirectory string) { // force the command to combine stderr(2) into stdout(1) linuxCommand += " 2>&1" cmd := exec.Command("bash", "-c", linuxCommand) cmd.Dir = workingDirectory cmd.Env = append(os.Environ(), "TERM=vt100", "LINES=24", "COLUMNS=80", ) stdout, err := cmd.StdoutPipe() if err != nil { fmt.Printf("Failed to set stdout\n") comm.WriteString("Failed to set stdout\r") return } stdin, err := cmd.StdinPipe() if err != nil { fmt.Printf("Failed to set stdin\n") comm.WriteString("Failed to set stdin\r") return } fmt.Printf("Command output:\n") err = cmd.Start() if err != nil { fmt.Printf("Failed to start command\n") comm.WriteString("Failed to start command\r") return } outputComplete := make(chan bool) inputComplete := make(chan bool) userCancelled := make(chan bool) go getStdin(stdin, outputComplete, inputComplete, userCancelled) go getStdout(stdout, outputComplete, userCancelled) for { select { case <-outputComplete: outputComplete <- true cmd.Wait() comm.WriteByte(0) return case <-userCancelled: userCancelled <- true cmd.Process.Kill() return case <-inputComplete: cmd.Wait() comm.WriteByte(0) return } } } func getStdout(stdout io.ReadCloser, outputComplete chan bool, userCancelled chan bool) { for { select { case <-userCancelled: fmt.Printf("User Cancelled stdout\n") stdout.Close() return default: bb := make([]byte, 1) n, err := stdout.Read(bb) if err != nil { stdout.Close() outputComplete <- true return } if n > 0 { b := bb[0] comm.SendCharacter(b) } } } } func getStdin(stdin io.WriteCloser, done chan bool, inputComplete chan bool, userCancelled chan bool) { for { select { case <-done: stdin.Close() inputComplete <- true return default: b, err := comm.ReadByte() if err == nil { if b == 0x00 || b == 0x03 { stdin.Close() userCancelled <- true fmt.Printf("\nUser cancelled stdin\n") return } bb := make([]byte, 1) stdin.Write(bb) } } } } func a2help() { comm.WriteString("\r" + "Built-in commands:\r" + "------------------\r" + "a2help - display this message\r" + "a2wifi - set up wifi\r" + "A2LOWER - force lowercase for II+\r" + "a2lower - disable force lowercase for II+\r" + "\r") } func a2lower(enable bool) { forceLowercase = enable comm.WriteString(fmt.Sprintf("All commands will be converted to lowercase: %t\r", forceLowercase)) } func a2wifi() { comm.WriteString("\r" + "Usage: a2wifi list\r" + " a2wifi select SSID PASSWORD REGION\r" + "\r") } func a2wifiList() string { return "sudo iwlist wlan0 scanning | grep ESSID | sed s/.*ESSID://g | sed s/\\\"//g" } func a2wifiSelect(linuxCommand string) (string, error) { params := strings.Fields(linuxCommand) if len(params) != 5 { comm.WriteString("\rIncorrect number of parameters. Usage: a2wifi select SSID PASSWORD REGION\r\r") return "", errors.New("Incorrect number of parameters. Usage: a2wifi select SSID PASSWORD REGION") } ssid := params[2] psk := params[3] region := params[4] linuxCommand = "printf \"country=%s\\nupdate_config=1\\nctrl_interface=/var/run/wpa_supplicant\\n\\nnetwork={\\n scan_ssid=1\\n ssid=\\\"%s\\\"\n psk=\\\"%s\\\"\\n}\\n\" " + region + " " + ssid + " " + psk + " " + " > /tmp/wpa_supplicant.conf; " + "sudo mv /tmp/wpa_supplicant.conf /etc/wpa_supplicant/; " + "sudo wpa_cli -i wlan0 reconfigure" return linuxCommand, nil }