Feat: conditional permissions behavior (#28)

* Fix: don't need sudo if we're root + other aesthetics

* Heavy refactoring, see PR #28

* Fix: avoid silent fatalities

demo: https://tcp.ac/i/JMSUc.gif

* Fix: Inverse check on `IsRoot`

* D.R.Y: check for permissions error in `common.ErrorCheck`

Reduce cognitive complexity.

* Fix: Issue with copying

* Resolve #28 (comment)

* Resolve #28 (comment) and #28 (comment)

* Revert "Resolve #28 (comment) and #28 (comment)"

This reverts commit ce15213.

* Resolve #28 (comment)

Author: yunginnanet

internal/common/errors.go

@@ -0,0 +1,50 @@
+package common
+
+import (
+	"errors"
+	"os"
+	"time"
+
+	"github.com/HikariKnight/ls-iommu/pkg/errorcheck"
+	"github.com/gookit/color"
+)
+
+const PermissionNotice = `
+<yellowB>Permissions error occured during file operations.</>
+
+<blue_b>Hint</>:
+
+	If you initially ran QuickPassthrough as root or using sudo,
+	but are now running it as a normal user, this is expected behavior.
+
+	<us>Try running QuickPassthrough as root or using sudo if so.</>
+
+	If this does not work, double check your filesystem's permissions,
+	and be sure to check the debug log for more information.
+`
+
+// ErrorCheck serves as a wrapper for HikariKnight/ls-iommu/pkg/common.ErrorCheck that allows for visibile error messages
+func ErrorCheck(err error, msg ...string) {
+	_, _ = os.Stdout.WriteString("\033[H\033[2J") // clear the screen
+	if err == nil {
+		return
+	}
+	if errors.Is(err, os.ErrPermission) {
+		color.Printf(PermissionNotice)
+	}
+	oneMsg := ""
+	if len(msg) < 1 {
+		oneMsg = ""
+	} else {
+		for _, v := range msg {
+			oneMsg += v + "\n"
+		}
+	}
+	color.Printf("\n<red_b>FATAL</>: %s\n%s\nAborting", err.Error(), oneMsg)
+	for i := 0; i < 10; i++ {
+		time.Sleep(1 * time.Second)
+		print(".")
+	}
+	print("\n")
+	errorcheck.ErrorCheck(err, msg...)
+}

internal/configs/config_bootloaders.go

@@ -1,16 +1,19 @@
 package configs
 
 import (
+	"errors"
 	"fmt"
 	"os"
+	"os/exec"
 	"regexp"
 	"strings"
 
-	"github.com/HikariKnight/ls-iommu/pkg/errorcheck"
+	"github.com/klauspost/cpuid/v2"
+
+	"github.com/HikariKnight/quickpassthrough/internal/common"
 	"github.com/HikariKnight/quickpassthrough/internal/logger"
 	"github.com/HikariKnight/quickpassthrough/pkg/command"
 	"github.com/HikariKnight/quickpassthrough/pkg/fileio"
-	"github.com/klauspost/cpuid/v2"
 )
 
 // This function just adds what bootloader the system has to our config.bootloader value
@@ -70,39 +73,32 @@ func Set_Cmdline(gpu_IDs []string) {
 	fileio.AppendContent(fmt.Sprintf(" vfio_pci.ids=%s", strings.Join(gpu_IDs, ",")), config.Path.CMDLINE)
 }
 
-// Configures systemd-boot using kernelstub
-func Set_KernelStub() string {
+// Set_KernelStub configures systemd-boot using kernelstub.
+func Set_KernelStub(isRoot bool) {
 	// Get the config
 	config := GetConfig()
 
 	// Get the kernel args
 	kernel_args := fileio.ReadFile(config.Path.CMDLINE)
 
-	// Write to logger
-	logger.Printf("Running command:\nsudo kernelstub -a \"%s\"\n", kernel_args)
-
-	// Run the command
-	_, err := command.Run("sudo", "kernelstub", "-a", kernel_args)
-	errorcheck.ErrorCheck(err, "Error, kernelstub command returned exit code 1")
-
-	// Return what we did
-	return fmt.Sprintf("Executed: sudo kernelstub -a \"%s\"", kernel_args)
+	// Run and log, check for errors
+	common.ErrorCheck(
+		command.ExecAndLogSudo(isRoot, true, "kernelstub", "-a", kernel_args),
+		"Error, kernelstub command returned exit code 1",
+	)
 }
 
-// Configures grub2 and/or systemd-boot using grubby
-func Set_Grubby() string {
+// Set_Grubby configures grub2 and/or systemd-boot using grubby
+func Set_Grubby(isRoot bool) string {
 	// Get the config
 	config := GetConfig()
 
 	// Get the kernel args
 	kernel_args := fileio.ReadFile(config.Path.CMDLINE)
 
-	// Write to logger
-	logger.Printf("Running command:\nsudo grubby --update-kernel=ALL --args=\"%s\"\n", kernel_args)
-
-	// Run the command
-	_, err := command.Run("sudo", "grubby", "--update-kernel=ALL", fmt.Sprintf("--args=%s", kernel_args))
-	errorcheck.ErrorCheck(err, "Error, grubby command returned exit code 1")
+	// Run and log, check for errors
+	err := command.ExecAndLogSudo(isRoot, true, "grubby", "--update-kernel=ALL", fmt.Sprintf("--args=%s", kernel_args))
+	common.ErrorCheck(err, "Error, grubby command returned exit code 1")
 
 	// Return what we did
 	return fmt.Sprintf("Executed: sudo grubby --update-kernel=ALL --args=\"%s\"", kernel_args)
@@ -116,8 +112,8 @@ func Configure_Grub2() {
 	conffile := fmt.Sprintf("%s/grub", config.Path.DEFAULT)
 
 	// Make sure we start from scratch by deleting any old file
-	if fileio.FileExist(conffile) {
-		os.Remove(conffile)
+	if exists, _ := fileio.FileExist(conffile); exists {
+		_ = os.Remove(conffile)
 	}
 
 	// Make a regex to get the system path instead of the config path
@@ -201,8 +197,8 @@ func clean_Grub2_Args(old_kernel_args []string) []string {
 	return clean_kernel_args
 }
 
-// This function copies our config to /etc/default/grub and updates grub
-func Set_Grub2() ([]string, error) {
+// Set_Grub2 copies our config to /etc/default/grub and updates grub
+func Set_Grub2(isRoot bool) error {
 	// Get the config
 	config := GetConfig()
 
@@ -213,38 +209,45 @@ func Set_Grub2() ([]string, error) {
 	sysfile_re := regexp.MustCompile(`^config`)
 	sysfile := sysfile_re.ReplaceAllString(conffile, "")
 
-	// Write to logger
-	logger.Printf("Executing command:\nsudo cp -v \"%s\" %s\n", conffile, sysfile)
-
-	// Make our output slice
-	var output []string
+	// [CopyToSystem] will log the operation
+	// logger.Printf("Executing command:\nsudo cp -v \"%s\" %s\n", conffile, sysfile)
 
-	// Copy files to system
-	output = append(output, CopyToSystem(conffile, sysfile))
+	// Copy files to system, logging and error checking is done in the function
+	CopyToSystem(isRoot, conffile, sysfile)
 
 	// Set a variable for the mkconfig command
-	mkconfig := "grub-mkconfig"
+	var mkconfig string
+	var grubPath = "/boot/grub/grub.cfg"
+	var lpErr error
+
 	// Check for grub-mkconfig
-	_, err := command.Run("which", "grub-mkconfig")
-	if err == nil {
-		// Set binary as grub-mkconfig
-		mkconfig = "grub-mkconfig"
-	} else {
-		mkconfig = "grub2-mkconfig"
+	mkconfig, lpErr = exec.LookPath("grub-mkconfig")
+	switch {
+	case errors.Is(lpErr, exec.ErrNotFound) || mkconfig == "":
+		// Check for grub2-mkconfig
+		mkconfig, lpErr = exec.LookPath("grub2-mkconfig")
+		if lpErr == nil && mkconfig != "" {
+			grubPath = "/boot/grub2/grub.cfg"
+			break // skip below, we found grub2-mkconfig
+		}
+		if lpErr == nil {
+			// we know mkconfig is empty despite no error;
+			// so set an error for [common.ErrorCheck].
+			lpErr = errors.New("neither grub-mkconfig or grub2-mkconfig found")
+		}
+		common.ErrorCheck(lpErr, lpErr.Error()+"\n")
+		return lpErr // note: unreachable as [common.ErrorCheck] calls fatal
+	default:
 	}
 
-	// Update grub.cfg
-	if fileio.FileExist("/boot/grub/grub.cfg") {
-		output = append(output, fmt.Sprintf("Executed: sudo %s -o /boot/grub/grub.cfg\nSee debug.log for more detailed output", mkconfig))
-		_, mklog, err := command.RunErr("sudo", mkconfig, "-o", "/boot/grub/grub.cfg")
-		logger.Printf(strings.Join(mklog, "\n"))
-		errorcheck.ErrorCheck(err, "Failed to update /boot/grub/grub.cfg")
-	} else {
-		output = append(output, fmt.Sprintf("Executed: sudo %s -o /boot/grub/grub.cfg\nSee debug.log for more detailed output", mkconfig))
-		_, mklog, err := command.RunErr("sudo", mkconfig, "-o", "/boot/grub2/grub.cfg")
-		logger.Printf(strings.Join(mklog, "\n"))
-		errorcheck.ErrorCheck(err, "Failed to update /boot/grub/grub.cfg")
-	}
+	_, mklog, err := command.RunErrSudo(isRoot, mkconfig, "-o", grubPath)
+
+	// tabulate the output, [command.RunErrSudo] logged the execution.
+	logger.Printf("\t" + strings.Join(mklog, "\n\t"))
+	common.ErrorCheck(err, "Failed to update /boot/grub/grub.cfg")
 
-	return output, err
+	// always returns nil as [common.ErrorCheck] calls fatal
+	// keeping the ret signature, as we should consider passing down errors
+	// but that's a massive rabbit hole to go down for this codebase as a whole
+	return err
 }

internal/configs/config_dracut.go

@@ -9,16 +9,16 @@ import (
 	"github.com/HikariKnight/quickpassthrough/pkg/fileio"
 )
 
-// This function writes a dracut configuration file for /etc/dracut.conf.d/
+// Set_Dracut writes a dracut configuration file for `/etc/dracut.conf.d/`.
 func Set_Dracut() {
 	config := GetConfig()
 
 	// Set the dracut config file
 	dracutConf := fmt.Sprintf("%s/vfio.conf", config.Path.DRACUT)
 
 	// If the file already exists then delete it
-	if fileio.FileExist(dracutConf) {
-		os.Remove(dracutConf)
+	if exists, _ := fileio.FileExist(dracutConf); exists {
+		_ = os.Remove(dracutConf)
 	}
 
 	// Write to logger

internal/configs/config_initramfstools.go

@@ -7,15 +7,15 @@ import (
 	"regexp"
 	"strings"
 
-	"github.com/HikariKnight/ls-iommu/pkg/errorcheck"
+	"github.com/HikariKnight/quickpassthrough/internal/common"
 	"github.com/HikariKnight/quickpassthrough/pkg/fileio"
 )
 
 // Special function to read the header of a file (reads the first N lines)
 func initramfs_readHeader(lines int, fileName string) string {
 	// Open the file
 	f, err := os.Open(fileName)
-	errorcheck.ErrorCheck(err, fmt.Sprintf("Error opening %s", fileName))
+	common.ErrorCheck(err, fmt.Sprintf("Error opening %s", fileName))
 	defer f.Close()
 
 	header_re := regexp.MustCompile(`^#`)
@@ -50,7 +50,7 @@ func initramfs_addModules(conffile string) {
 
 	// Open the system file for reading
 	sysfile, err := os.Open(syspath)
-	errorcheck.ErrorCheck(err, fmt.Sprintf("Error opening file for reading %s", syspath))
+	common.ErrorCheck(err, fmt.Sprintf("Error opening file for reading %s", syspath))
 	defer sysfile.Close()
 
 	// Check if user has vendor-reset installed/enabled and make sure that is first

internal/configs/config_mkinitcpio.go

@@ -10,14 +10,14 @@ import (
 	"github.com/HikariKnight/quickpassthrough/pkg/fileio"
 )
 
-// This function copies the content of /etc/mkinitcpio.conf to the config folder and does an inline replace/insert on the MODULES=() line
+// Set_Mkinitcpio copies the content of /etc/mkinitcpio.conf to the config folder and does an inline replace/insert on the MODULES=() line
 func Set_Mkinitcpio() {
 	// Get the config struct
 	config := GetConfig()
 
 	// Make sure we start from scratch by deleting any old file
-	if fileio.FileExist(config.Path.MKINITCPIO) {
-		os.Remove(config.Path.MKINITCPIO)
+	if exists, _ := fileio.FileExist(config.Path.MKINITCPIO); exists {
+		_ = os.Remove(config.Path.MKINITCPIO)
 	}
 
 	// Make a regex to get the system path instead of the config path

internal/configs/config_modprobe.go

@@ -30,9 +30,9 @@ func Set_Modprobe(gpu_IDs []string) {
 	conffile := fmt.Sprintf("%s/vfio.conf", config.Path.MODPROBE)
 
 	// If the file exists
-	if fileio.FileExist(conffile) {
+	if exists, _ := fileio.FileExist(conffile); exists {
 		// Delete the old file
-		os.Remove(conffile)
+		_ = os.Remove(conffile)
 	}
 
 	content := fmt.Sprint(

internal/configs/config_vbios_dumper.go

@@ -6,7 +6,7 @@ import (
 	"path/filepath"
 	"strings"
 
-	"github.com/HikariKnight/ls-iommu/pkg/errorcheck"
+	"github.com/HikariKnight/quickpassthrough/internal/common"
 	"github.com/HikariKnight/quickpassthrough/internal/logger"
 )
 
@@ -55,12 +55,12 @@ func GenerateVBIOSDumper(vbios_path string) {
 
 	// Make the script file
 	scriptfile, err := os.Create("utils/dump_vbios.sh")
-	errorcheck.ErrorCheck(err, "Cannot create file \"utils/dump_vbios.sh\"")
+	common.ErrorCheck(err, "Cannot create file \"utils/dump_vbios.sh\"")
 	defer scriptfile.Close()
 
 	// Make the script executable
 	scriptfile.Chmod(0775)
-	errorcheck.ErrorCheck(err, "Could not change permissions of \"utils/dump_vbios.sh\"")
+	common.ErrorCheck(err, "Could not change permissions of \"utils/dump_vbios.sh\"")
 
 	// Write to logger
 	logger.Printf("Writing utils/dump_vbios.sh\n")

internal/configs/config_vfio_video.go

@@ -5,7 +5,7 @@ import (
 	"os"
 	"strings"
 
-	"github.com/HikariKnight/ls-iommu/pkg/errorcheck"
+	"github.com/HikariKnight/quickpassthrough/internal/common"
 	"github.com/HikariKnight/quickpassthrough/internal/logger"
 	"github.com/HikariKnight/quickpassthrough/pkg/fileio"
 )
@@ -26,7 +26,7 @@ func DisableVFIOVideo(i int) {
 	if strings.Contains(kernel_args, "vfio_pci.disable_vga") {
 		// Remove the old file
 		err := os.Remove(config.Path.CMDLINE)
-		errorcheck.ErrorCheck(err, fmt.Sprintf("Could not rewrite %s", config.Path.CMDLINE))
+		common.ErrorCheck(err, fmt.Sprintf("Could not rewrite %s", config.Path.CMDLINE))
 
 		// Enable or disable the VGA based on our given value
 		if i == 0 {