Added versioning - 0.1.2

Go/main.go

@@ -2,10 +2,12 @@ package main
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"os"
 	"os/exec"
 	"regexp"
+	"strconv"
 	"strings"
 )
 
@@ -13,7 +15,7 @@ var (
 	tmpDir  string
 	numeric = regexp.MustCompile(`^[0-9]+$`)
 )
-
+const version = "V0.1.2"
 func main() {
 	if os.Geteuid() != 0 {
 		fmt.Fprintf(os.Stderr, "Run this program as root, for example: sudo %s\n", os.Args[0])
@@ -36,21 +38,8 @@ func main() {
 	mainMenu()
 }
 
-// menu displays a whiptail menu and returns the selected tag.
-// An empty selection means the user cancelled or pressed Esc.
-func menu(title, prompt string, height, width, menuHeight int, items ...string) string {
-	args := []string{
-		"--title", title,
-		"--menu", prompt,
-		fmt.Sprint(height), fmt.Sprint(width), fmt.Sprint(menuHeight),
-	}
-	args = append(args, items...)
-
-	return whiptail(args...)
-}
-
-// dialog runs whiptail and captures its result through file descriptor 3.
-// The menu itself continues to use the terminal.
+// whiptail runs a dialog and captures its selected value through file
+// descriptor 3. The dialog itself uses the terminal.
 func whiptail(args ...string) string {
 	readEnd, writeEnd, err := os.Pipe()
 	if err != nil {
@@ -66,7 +55,7 @@ func whiptail(args ...string) string {
 	cmd.ExtraFiles = []*os.File{writeEnd}
 
 	err = cmd.Run()
-	writeEnd.Close()
+	_ = writeEnd.Close()
 
 	var result bytes.Buffer
 	_, _ = result.ReadFrom(readEnd)
@@ -76,16 +65,22 @@ func whiptail(args ...string) string {
 	return strings.TrimSpace(result.String())
 }
 
+func menu(title, prompt string, height, width, menuHeight int, items ...string) string {
+	args := []string{
+		"--title", title,
+		"--menu", prompt,
+		strconv.Itoa(height),
+		strconv.Itoa(width),
+		strconv.Itoa(menuHeight),
+	}
+	args = append(args, items...)
+	return whiptail(args...)
+}
+
 func message(title, text string) {
 	whiptail("--title", title, "--msgbox", text, "8", "70")
 }
 
-func confirm(text string) bool {
-	return whiptail("--title", "Confirm", "--yesno", text, "10", "70") == ""
-}
-
-// Yes/no dialogs also return an empty string on success, so use this
-// separate helper to distinguish Yes from No or Esc by the process status.
 func confirmAction(text string) bool {
 	readEnd, writeEnd, err := os.Pipe()
 	if err != nil {
@@ -94,7 +89,10 @@ func confirmAction(text string) bool {
 	defer readEnd.Close()
 
 	cmd := exec.Command(
-		"whiptail", "--title", "Confirm", "--yesno", text, "10", "70",
+		"whiptail",
+		"--title", "Confirm",
+		"--yesno", text,
+		"10", "70",
 	)
 	cmd.Stdin = os.Stdin
 	cmd.Stdout = os.Stdout
@@ -102,18 +100,10 @@ func confirmAction(text string) bool {
 	cmd.ExtraFiles = []*os.File{writeEnd}
 
 	err = cmd.Run()
-	writeEnd.Close()
-	_, _ = readEnd.Read(make([]byte, 1))
+	_ = writeEnd.Close()
 	return err == nil
 }
 
-func input(title, prompt string) (string, bool) {
-	value := whiptail("--title", title, "--inputbox", prompt, "9", "72")
-	// An empty value is valid for some prompts, so cancellation is
-	// determined by whiptail itself in inputValue below when needed.
-	return value, true
-}
-
 func inputValue(title, prompt string) (string, bool) {
 	readEnd, writeEnd, err := os.Pipe()
 	if err != nil {
@@ -121,15 +111,20 @@ func inputValue(title, prompt string) (string, bool) {
 	}
 	defer readEnd.Close()
 
-	cmd := exec.Command("whiptail", "--output-fd", "3",
-		"--title", title, "--inputbox", prompt, "9", "72")
+	cmd := exec.Command(
+		"whiptail",
+		"--output-fd", "3",
+		"--title", title,
+		"--inputbox", prompt,
+		"9", "72",
+	)
 	cmd.Stdin = os.Stdin
 	cmd.Stdout = os.Stdout
 	cmd.Stderr = os.Stderr
 	cmd.ExtraFiles = []*os.File{writeEnd}
 
 	err = cmd.Run()
-	writeEnd.Close()
+	_ = writeEnd.Close()
 
 	var result bytes.Buffer
 	_, _ = result.ReadFrom(readEnd)
@@ -141,8 +136,10 @@ func inputValue(title, prompt string) (string, bool) {
 
 func requireCommand(name string) bool {
 	if _, err := exec.LookPath(name); err != nil {
-		message("Command unavailable",
-			fmt.Sprintf("The command '%s' is not installed or not available on this node.", name))
+		message(
+			"Command unavailable",
+			fmt.Sprintf("The command '%s' is not installed or not available on this node.", name),
+		)
 		return false
 	}
 	return true
@@ -160,8 +157,22 @@ func askID(prompt string) (string, bool) {
 	return value, true
 }
 
+func terminalSize(name string, fallback int) int {
+	out, err := exec.Command("tput", name).Output()
+	if err != nil {
+		return fallback
+	}
+
+	value, err := strconv.Atoi(strings.TrimSpace(string(out)))
+	if err != nil || value <= 0 {
+		return fallback
+	}
+	return value
+}
+
 func showOutput(title string, name string, args ...string) {
 	outputPath := tmpDir + "/output.txt"
+
 	output, err := os.Create(outputPath)
 	if err != nil {
 		message("Error", "Could not create a temporary output file.")
@@ -174,24 +185,113 @@ func showOutput(title string, name string, args ...string) {
 	runErr := cmd.Run()
 	_ = output.Close()
 
+	status := 0
+	if runErr != nil {
+		status = 1
+		var exitErr *exec.ExitError
+		if errors.As(runErr, &exitErr) {
+			status = exitErr.ExitCode()
+		}
+	}
+
 	data, _ := os.ReadFile(outputPath)
 	if len(data) == 0 {
-		status := 0
-		if runErr != nil {
-			status = 1
-		}
-		data = []byte(fmt.Sprintf("Command completed with exit status %d; no output.\n", status))
-	} else if runErr != nil {
-		data = append(data, []byte("\nCommand exited with an error.\n")...)
+		data = []byte(fmt.Sprintf(
+			"Command completed with exit status %d; no output.\n",
+			status,
+		))
+	} else if status != 0 {
+		data = append(data, []byte(fmt.Sprintf(
+			"\nCommand exited with status %d.\n",
+			status,
+		))...)
 	}
-	_ = os.WriteFile(outputPath, data, 0600)
 
-	whiptail("--title", title, "--textbox", outputPath, "24", "85")
+	if err := os.WriteFile(outputPath, data, 0600); err != nil {
+		message("Error", "Could not write command output to the temporary file.")
+		return
+	}
+
+	// Leave room around the dialog and use fallback dimensions if tput fails.
+	height := terminalSize("lines", 24) - 4
+	width := terminalSize("cols", 80) - 4
+
+	// Keep dimensions within whiptail's practical limits.
+	if height < 12 {
+		height = 12
+	}
+	if width < 50 {
+		width = 50
+	}
+
+	whiptail(
+		"--title", title,
+		"--textbox", outputPath,
+		strconv.Itoa(height),
+		strconv.Itoa(width),
+	)
+}
+
+func showMemory(title, id string) {
+	output, err := exec.Command("qm", "config", id).CombinedOutput()
+	if err != nil {
+		status := 1
+		var exitErr *exec.ExitError
+		if errors.As(err, &exitErr) {
+			status = exitErr.ExitCode()
+		}
+		text := string(output)
+		if text != "" {
+			text += "\n"
+		}
+		text += fmt.Sprintf("Command exited with status %d.\n", status)
+		showText(title, text)
+		return
+	}
+
+	var matches []string
+	for _, line := range strings.Split(string(output), "\n") {
+		if strings.HasPrefix(line, "memory:") {
+			matches = append(matches, line)
+		}
+	}
+	if len(matches) == 0 {
+		matches = []string{"No memory setting found."}
+	}
+
+	showText(title, strings.Join(matches, "\n")+"\n")
+}
+
+func showText(title, text string) {
+	outputPath := tmpDir + "/output.txt"
+	if err := os.WriteFile(outputPath, []byte(text), 0600); err != nil {
+		message("Error", "Could not write command output to the temporary file.")
+		return
+	}
+
+	height := terminalSize("lines", 24) - 4
+	width := terminalSize("cols", 80) - 4
+	if height < 12 {
+		height = 12
+	}
+	if width < 50 {
+		width = 50
+	}
+
+	whiptail(
+		"--title", title,
+		"--textbox", outputPath,
+		strconv.Itoa(height),
+		strconv.Itoa(width),
+	)
 }
 
 func vmMenu() {
 	for {
-		choice := menu("Virtual Machines (QEMU)", "Choose an action:", 16, 72, 8,
+		choice := menu(
+			"Virtual Machines (QEMU)",
+			"Choose an action:",
+			16, 72, 8,
 			"list", "List VMs (qm list)",
 			"config", "Show VM configuration",
 			"memory", "Show VM memory setting",
@@ -208,6 +308,7 @@ func vmMenu() {
 			if !requireCommand("qm") {
 				continue
 			}
+
 			id, ok := askID("Enter the VMID:")
 			if !ok {
 				continue
@@ -217,9 +318,12 @@ func vmMenu() {
 			case "config":
 				showOutput("VM "+id+" configuration", "qm", "config", id)
 			case "memory":
-				showMemory("VM "+id+" memory", "qm", "config", id, "^memory:")
+				showMemory("VM "+id+" memory", id)
 			case "unlock":
-				if confirmAction("Unlock VM " + id + "?\n\nOnly do this if you have confirmed that no task is still running for this VM.") {
+				if confirmAction(
+					"Unlock VM " + id + "?\n\n" +
+						"Only do this if you have confirmed that no task is still running for this VM.",
+				) {
 					showOutput("Unlock VM "+id, "qm", "unlock", id)
 				}
 			}
@@ -229,31 +333,12 @@ func vmMenu() {
 	}
 }
 
-func showMemory(title, command string, args ...string) {
-	output, err := exec.Command(command, args[:len(args)-1]...).CombinedOutput()
-	if err != nil {
-		showOutput(title, command, args[:len(args)-1]...)
-		return
-	}
-
-	var matches []string
-	for _, line := range strings.Split(string(output), "\n") {
-		if matched, _ := regexp.MatchString(args[len(args)-1], line); matched {
-			matches = append(matches, line)
-		}
-	}
-	if len(matches) == 0 {
-		matches = []string{"No memory setting found."}
-	}
-
-	path := tmpDir + "/output.txt"
-	_ = os.WriteFile(path, []byte(strings.Join(matches, "\n")+"\n"), 0600)
-	whiptail("--title", title, "--textbox", path, "24", "85")
-}
-
 func containerMenu() {
 	for {
-		choice := menu("Containers (LXC)", "Choose an action:", 14, 72, 6,
+		choice := menu(
+			"Containers (LXC)",
+			"Choose an action:",
+			14, 72, 6,
 			"list", "List containers (pct list)",
 			"config", "Show container configuration",
 			"unlock", "Unlock a container",
@@ -269,13 +354,18 @@ func containerMenu() {
 			if !requireCommand("pct") {
 				continue
 			}
+
 			id, ok := askID("Enter the container ID:")
 			if !ok {
 				continue
 			}
+
 			if choice == "config" {
 				showOutput("Container "+id+" configuration", "pct", "config", id)
-			} else if confirmAction("Unlock container " + id + "?\n\nOnly do this if you have confirmed that no task is still running for this container.") {
+			} else if confirmAction(
+				"Unlock container " + id + "?\n\n" +
+					"Only do this if you have confirmed that no task is still running for this container.",
+			) {
 				showOutput("Unlock container "+id, "pct", "unlock", id)
 			}
 		case "back", "":
@@ -288,17 +378,25 @@ func backupMenu() {
 	if !requireCommand("vzdump") {
 		return
 	}
+
 	id, ok := askID("Enter the VM or container ID to back up:")
 	if !ok {
 		return
 	}
-	if confirmAction("Start a backup for ID " + id + " using vzdump defaults?\n\nReview your node's backup configuration and storage capacity first.") {
+
+	if confirmAction(
+		"Start a backup for ID " + id + " using vzdump defaults?\n\n" +
+			"Review your node's backup configuration and storage capacity first.",
+	) {
 		showOutput("Backup ID "+id, "vzdump", id)
 	}
 }
 
 func restoreMenu() {
-	choice := menu("Restore", "Choose what to restore:", 12, 72, 4,
+	choice := menu(
+		"Restore",
+		"Choose what to restore:",
+		12, 72, 4,
 		"vm", "Restore a QEMU VM (qmrestore)",
 		"ct", "Restore a container (pct restore)",
 		"back", "Back",
@@ -311,17 +409,25 @@ func restoreMenu() {
 	if !ok {
 		return
 	}
-	archive, ok := inputValue("Backup archive", "Enter the full path to the vzdump archive:")
+
+	archive, ok := inputValue(
+		"Backup archive",
+		"Enter the full path to the vzdump archive:",
+	)
 	if !ok {
 		return
 	}
+
 	info, err := os.Stat(archive)
 	if archive == "" || err != nil || !info.Mode().IsRegular() {
 		message("Archive not found", "That file does not exist or is not a regular file.")
 		return
 	}
 
-	if !confirmAction("Restore '" + archive + "' as ID " + id + "?\n\nRestoring can create or overwrite resources. Confirm the target ID and archive carefully.") {
+	if !confirmAction(
+		"Restore '" + archive + "' as ID " + id + "?\n\n" +
+			"Restoring can create or overwrite resources. Confirm the target ID and archive carefully.",
+	) {
 		return
 	}
 
@@ -336,7 +442,10 @@ func restoreMenu() {
 
 func storageMenu() {
 	for {
-		choice := menu("Storage / LVM", "Choose a read-only report:", 14, 72, 6,
+		choice := menu(
+			"Storage / LVM",
+			"Choose a read-only report:",
+			14, 72, 6,
 			"pvs", "Physical volumes (pvs)",
 			"vgs", "Volume groups (vgs)",
 			"lvs", "Logical volumes (lvs)",
@@ -344,13 +453,17 @@ func storageMenu() {
 		)
 
 		switch choice {
-		case "pvs", "vgs", "lvs":
-			if requireCommand(choice) {
-				showOutput(map[string]string{
-					"pvs": "Physical volumes",
-					"vgs": "Volume groups",
-					"lvs": "Logical volumes",
-				}[choice], choice)
+		case "pvs":
+			if requireCommand("pvs") {
+				showOutput("Physical volumes", "pvs")
+			}
+		case "vgs":
+			if requireCommand("vgs") {
+				showOutput("Volume groups", "vgs")
+			}
+		case "lvs":
+			if requireCommand("lvs") {
+				showOutput("Logical volumes", "lvs")
 			}
 		case "back", "":
 			return
@@ -360,7 +473,10 @@ func storageMenu() {
 
 func mainMenu() {
 	for {
-		choice := menu("Proxmox VE Toolkit", "Select a task:", 21, 76, 13,
+		choice := menu(
+			"Proxmox VE Toolkit "+version,
+			"Select a task:",
+			21, 76, 13,
 			"vms", "Virtual machines (QEMU)",
 			"containers", "Containers (LXC)",
 			"backup", "Back up a VM or container (vzdump)",
@@ -394,7 +510,8 @@ func mainMenu() {
 		case "storage":
 			storageMenu()
 		case "perf":
-			if requireCommand("pveperf") && confirmAction("Run pveperf?\n\nThis can cause temporary disk activity.") {
+			if requireCommand("pveperf") &&
+				confirmAction("Run pveperf?\n\nThis can cause temporary disk activity.") {
 				showOutput("Host performance", "pveperf")
 			}
 		case "subscription":