X-Git-Url: https://ruderich.org/simon/gitweb/?a=blobdiff_plain;f=remote%2Fainsl%2Fainsl.go;h=6437a5a08a5745237731325e084af4dcfa3be5f9;hb=refs%2Fheads%2Fmaster;hp=d716b2b4d5ce0868b4006a19ed47acb3f7da5ece;hpb=9269fa3c94e700afc0be823f58ea473a2db8f3dc;p=safcm%2Fsafcm.git

diff --git a/remote/ainsl/ainsl.go b/remote/ainsl/ainsl.go
index d716b2b..6437a5a 100644
--- a/remote/ainsl/ainsl.go
+++ b/remote/ainsl/ainsl.go
@@ -4,20 +4,8 @@
 //
 // FAI: https://fai-project.org
 
-// Copyright (C) 2021  Simon Ruderich
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+// SPDX-License-Identifier: GPL-3.0-or-later
+// Copyright (C) 2021-2024  Simon Ruderich
 
 package ainsl
 
@@ -28,10 +16,11 @@ import (
 	"io"
 	"io/fs"
 	"os"
-	"path/filepath"
 	"strings"
 	"syscall"
 
+	"golang.org/x/sys/unix"
+
 	"ruderich.org/simon/safcm/remote/sync"
 )
 
@@ -46,7 +35,7 @@ func Main(args []string) error {
 	optionCreate := flag.Bool("create", false,
 		"create the path if it does not exist")
 
-	flag.CommandLine.Parse(args[2:])
+	flag.CommandLine.Parse(args[2:]) //nolint:errcheck
 
 	if flag.NArg() != 2 {
 		flag.Usage()
@@ -74,14 +63,20 @@ func handle(path string, line string, create bool) ([]string, error) {
 			line)
 	}
 
+	parentFd, baseName, err := sync.OpenParentDirectoryNoSymlinks(path)
+	if err != nil {
+		return nil, err
+	}
+	defer unix.Close(parentFd)
+
 	var changes []string
 
 	var uid, gid int
 	var mode fs.FileMode
-	data, stat, err := readFileNoFollow(path)
+	data, stat, err := readFileAtNoFollow(parentFd, baseName)
 	if err != nil {
 		if !os.IsNotExist(err) {
-			return nil, err
+			return nil, fmt.Errorf("%q: %v", path, err)
 		}
 		if !create {
 			return nil, fmt.Errorf(
@@ -112,7 +107,7 @@ func handle(path string, line string, create bool) ([]string, error) {
 		gid = int(x.Gid)
 		mode = stat.Mode()
 	}
-	stat = nil // prevent accidental use
+	stat = nil //nolint:wastedassign // prevent accidental use
 
 	// Check if the expected line is present
 	var found bool
@@ -147,18 +142,17 @@ func handle(path string, line string, create bool) ([]string, error) {
 	}
 
 	// Write via temporary file and rename
-	dir := filepath.Dir(path)
-	base := filepath.Base(path)
-	tmpPath, err := sync.WriteTemp(dir, "."+base, data, uid, gid, mode)
+	tmpBase, err := sync.WriteTempAt(parentFd, "."+baseName,
+		data, uid, gid, mode)
 	if err != nil {
 		return nil, err
 	}
-	err = os.Rename(tmpPath, path)
+	err = unix.Renameat(parentFd, tmpBase, parentFd, baseName)
 	if err != nil {
-		os.Remove(tmpPath)
+		unix.Unlinkat(parentFd, tmpBase, 0 /* flags */) //nolint:errcheck
 		return nil, err
 	}
-	err = sync.SyncPath(dir)
+	err = unix.Fsync(parentFd)
 	if err != nil {
 		return nil, err
 	}
@@ -166,8 +160,8 @@ func handle(path string, line string, create bool) ([]string, error) {
 	return changes, nil
 }
 
-func readFileNoFollow(path string) ([]byte, fs.FileInfo, error) {
-	fh, err := sync.OpenFileNoFollow(path)
+func readFileAtNoFollow(dirfd int, base string) ([]byte, fs.FileInfo, error) {
+	fh, err := sync.OpenAtNoFollow(dirfd, base)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -178,13 +172,13 @@ func readFileNoFollow(path string) ([]byte, fs.FileInfo, error) {
 		return nil, nil, err
 	}
 	if stat.Mode().Type() != 0 /* regular file */ {
-		return nil, nil, fmt.Errorf("%q is not a regular file but %s",
-			path, stat.Mode().Type())
+		return nil, nil, fmt.Errorf("not a regular file but %s",
+			stat.Mode().Type())
 	}
 
 	x, err := io.ReadAll(fh)
 	if err != nil {
-		return nil, nil, fmt.Errorf("%q: %v", path, err)
+		return nil, nil, err
 	}
 
 	return x, stat, nil