Fix fs error handling

cmds/portmaster-start/lock.go

@@ -33,7 +33,7 @@ func checkAndCreateInstanceLock(path, name string, perUser bool) (pid int32, err
 	// read current pid file
 	data, err := os.ReadFile(lockFilePath)
 	if err != nil {
-		if os.IsNotExist(err) {
+		if errors.Is(err, fs.ErrNotExist) {
 			// create new lock
 			return 0, createInstanceLock(lockFilePath)
 		}

cmds/updatemgr/sign.go

@@ -3,6 +3,7 @@ package main
 import (
 	"errors"
 	"fmt"
+	"io/fs"
 	"os"
 	"path/filepath"
 	"strings"
@@ -79,7 +80,7 @@ func sign(cmd *cobra.Command, args []string) error {
 			// Check if there is an existing signature.
 			_, err := os.Stat(file.Path() + filesig.Extension)
 			switch {
-			case err == nil || os.IsExist(err):
+			case err == nil || errors.Is(err, fs.ErrExist):
 				// If the file exists, just verify.
 				fileData, err := filesig.VerifyFile(
 					file.Path(),
@@ -97,7 +98,7 @@ func sign(cmd *cobra.Command, args []string) error {
 					verified++
 				}
 
-			case os.IsNotExist(err):
+			case errors.Is(err, fs.ErrNotExist):
 				// Attempt to sign file.
 				fileData, err := filesig.SignFile(
 					file.Path(),
@@ -123,10 +124,10 @@ func sign(cmd *cobra.Command, args []string) error {
 	}
 
 	if verified > 0 {
-		fmt.Printf("[STAT] verified %d files", verified)
+		fmt.Printf("[STAT] verified %d files\n", verified)
 	}
 	if signed > 0 {
-		fmt.Printf("[STAT] signed %d files", signed)
+		fmt.Printf("[STAT] signed %d files\n", signed)
 	}
 	if fails > 0 {
 		return fmt.Errorf("signing or verification failed on %d files", fails)
@@ -170,7 +171,7 @@ func signIndex(cmd *cobra.Command, args []string) error {
 		// Check if there is an existing signature.
 		_, err := os.Stat(sigFile)
 		switch {
-		case err == nil || os.IsExist(err):
+		case err == nil || errors.Is(err, fs.ErrExist):
 			// If the file exists, just verify.
 			fileData, err := filesig.VerifyFile(
 				file,
@@ -189,7 +190,7 @@ func signIndex(cmd *cobra.Command, args []string) error {
 			}
 
 			fallthrough
-		case os.IsNotExist(err):
+		case errors.Is(err, fs.ErrNotExist):
 			// Attempt to sign file.
 			fileData, err := filesig.SignFile(
 				file,

netenv/dbus_linux_test.go

@@ -1,6 +1,8 @@
 package netenv
 
 import (
+	"errors"
+	"io/fs"
 	"os"
 	"testing"
 )
@@ -12,7 +14,7 @@ func TestDbus(t *testing.T) {
 		t.Skip("skipping test in short mode because it fails in the CI")
 	}
 
-	if _, err := os.Stat("/var/run/dbus/system_bus_socket"); os.IsNotExist(err) {
+	if _, err := os.Stat("/var/run/dbus/system_bus_socket"); errors.Is(err, fs.ErrNotExist) {
 		t.Logf("skipping dbus tests, as dbus does not seem to be installed: %s", err)
 		return
 	}

network/proc/findpid.go

@@ -3,7 +3,9 @@
 package proc
 
 import (
+	"errors"
 	"fmt"
+	"io/fs"
 	"os"
 	"time"
 
@@ -103,7 +105,7 @@ func findSocketFromPid(pid int, socketName string) bool {
 	for _, entry := range entries {
 		link, err := os.Readlink(fmt.Sprintf("/proc/%d/fd/%s", pid, entry))
 		if err != nil {
-			if !os.IsNotExist(err) {
+			if !errors.Is(err, fs.ErrNotExist) {
 				log.Warningf("proc: failed to read link /proc/%d/fd/%s: %s", pid, entry, err)
 			}
 			continue
@@ -122,7 +124,7 @@ func findSocketFromPid(pid int, socketName string) bool {
 func readDirNames(dir string) (names []string) {
 	file, err := os.Open(dir)
 	if err != nil {
-		if !os.IsNotExist(err) {
+		if !errors.Is(err, fs.ErrNotExist) {
 			log.Warningf("proc: could not open directory %s: %s", dir, err)
 		}
 		return

network/proc/pids_by_user.go

@@ -3,7 +3,9 @@
 package proc
 
 import (
+	"errors"
 	"fmt"
+	"io/fs"
 	"os"
 	"strconv"
 	"sync"
@@ -50,7 +52,7 @@ func updatePids() {
 
 			statData, err := os.Stat(fmt.Sprintf("/proc/%d", pid))
 			if err != nil {
-				if !os.IsNotExist(err) {
+				if !errors.Is(err, fs.ErrNotExist) {
 					log.Warningf("proc: could not stat /proc/%d: %s", pid, err)
 				}
 				continue entryLoop

profile/framework.go

@@ -57,7 +57,7 @@ package profile
 // 				lastError = fmt.Errorf("constructed path \"%s\" from framework is not absolute", buildPath)
 // 				continue
 // 			}
-// 			if _, err := os.Stat(buildPath); os.IsNotExist(err) {
+// 			if _, err := os.Stat(buildPath); errors.Is(err, fs.ErrNotExist) {
 // 				lastError = fmt.Errorf("constructed path \"%s\" does not exist", buildPath)
 // 				continue
 // 			}

ui/serve.go

@@ -4,9 +4,9 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"io/fs"
 	"net/http"
 	"net/url"
-	"os"
 	"path/filepath"
 	"strings"
 	"sync"
@@ -125,7 +125,7 @@ func (bs *archiveServer) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 func ServeFileFromArchive(w http.ResponseWriter, r *http.Request, archiveName string, archiveFS *zipfs.FileSystem, path string) {
 	readCloser, err := archiveFS.Open(path)
 	if err != nil {
-		if os.IsNotExist(err) {
+		if errors.Is(err, fs.ErrNotExist) {
 			// Check if there is a base index.html file we can serve instead.
 			var indexErr error
 			path = "index.html"

updates/helper/indexes.go

@@ -1,7 +1,9 @@
 package helper
 
 import (
+	"errors"
 	"fmt"
+	"io/fs"
 	"os"
 	"path/filepath"
 
@@ -106,13 +108,13 @@ func indexExists(registry *updater.ResourceRegistry, indexPath string) bool {
 func deleteIndex(registry *updater.ResourceRegistry, indexPath string) error {
 	// Remove index itself.
 	err := os.Remove(filepath.Join(registry.StorageDir().Path, indexPath))
-	if err != nil && !os.IsNotExist(err) {
+	if err != nil && !errors.Is(err, fs.ErrNotExist) {
 		return err
 	}
 
 	// Remove any accompanying signature.
 	err = os.Remove(filepath.Join(registry.StorageDir().Path, indexPath+filesig.Extension))
-	if err != nil && !os.IsNotExist(err) {
+	if err != nil && !errors.Is(err, fs.ErrNotExist) {
 		return err
 	}