Add option to follow symbolic links

cmd/restic/cmd_backup.go

@@ -96,6 +96,7 @@ type BackupOptions struct {
 	FilesFromRaw            []string
 	TimeStamp               string
 	WithAtime               bool
+	FollowSymLinks          bool
 	IgnoreInode             bool
 	IgnoreCtime             bool
 	UseFsSnapshot           bool
@@ -138,6 +139,7 @@ func init() {
 	f.StringArrayVar(&backupOptions.FilesFromRaw, "files-from-raw", nil, "read the files to backup from `file` (can be combined with file args; can be specified multiple times)")
 	f.StringVar(&backupOptions.TimeStamp, "time", "", "`time` of the backup (ex. '2012-11-01 22:08:41') (default: now)")
 	f.BoolVar(&backupOptions.WithAtime, "with-atime", false, "store the atime for all files and directories")
+	f.BoolVar(&backupOptions.FollowSymLinks, "follow-symlinks", false, "treat symbolic links as transparent and dereference their destination")
 	f.BoolVar(&backupOptions.IgnoreInode, "ignore-inode", false, "ignore inode number changes when checking for modified files")
 	f.BoolVar(&backupOptions.IgnoreCtime, "ignore-ctime", false, "ignore ctime changes when checking for modified files")
 	f.BoolVarP(&backupOptions.DryRun, "dry-run", "n", false, "do not upload or write any data, just show what would be done")
@@ -679,6 +681,7 @@ func runBackup(opts BackupOptions, gopts GlobalOptions, term *termstatus.Termina
 	sc.Select = selectFilter
 	sc.Error = progressReporter.ScannerError
 	sc.Result = progressReporter.ReportTotal
+	sc.FollowSymLinks = opts.FollowSymLinks
 
 	if !gopts.JSON {
 		progressPrinter.V("start scan on %v", targets)
@@ -689,6 +692,7 @@ func runBackup(opts BackupOptions, gopts GlobalOptions, term *termstatus.Termina
 	arch.SelectByName = selectByNameFilter
 	arch.Select = selectFilter
 	arch.WithAtime = opts.WithAtime
+	arch.FollowSymLinks = opts.FollowSymLinks
 	success := true
 	arch.Error = func(item string, err error) error {
 		success = false

internal/archiver/archiver.go

@@ -83,6 +83,10 @@ type Archiver struct {
 	// default.
 	WithAtime bool
 
+	// When symbolic links are encountered, dereference them and access the
+	// content they point to instead.
+	FollowSymLinks bool
+
 	// Flags controlling change detection. See doc/040_backup.rst for details.
 	ChangeIgnoreFlags uint
 }
@@ -141,15 +145,16 @@ func (o Options) ApplyDefaults() Options {
 // New initializes a new archiver.
 func New(repo restic.Repository, fs fs.FS, opts Options) *Archiver {
 	arch := &Archiver{
-		Repo:         repo,
-		SelectByName: func(item string) bool { return true },
-		Select:       func(item string, fi os.FileInfo) bool { return true },
-		FS:           fs,
-		Options:      opts.ApplyDefaults(),
+		Repo:           repo,
+		SelectByName:   func(item string) bool { return true },
+		Select:         func(item string, fi os.FileInfo) bool { return true },
+		FS:             fs,
+		Options:        opts.ApplyDefaults(),
 
-		CompleteItem: func(string, *restic.Node, *restic.Node, ItemStats, time.Duration) {},
-		StartFile:    func(string) {},
-		CompleteBlob: func(string, uint64) {},
+		CompleteItem:   func(string, *restic.Node, *restic.Node, ItemStats, time.Duration) {},
+		StartFile:      func(string) {},
+		CompleteBlob:   func(string, uint64) {},
+		FollowSymLinks: false,
 	}
 
 	return arch
@@ -367,7 +372,12 @@ func (arch *Archiver) Save(ctx context.Context, snPath, target string, previous
 	}
 
 	// get file info and run remaining select functions that require file information
-	fi, err := arch.FS.Lstat(target)
+	var fi os.FileInfo
+	if arch.FollowSymLinks {
+		fi, err = arch.FS.Stat(target)
+	} else {
+		fi, err = arch.FS.Lstat(target)
+	}
 	if err != nil {
 		debug.Log("lstat() for %v returned error: %v", target, err)
 		err = arch.error(abstarget, err)

internal/archiver/scanner.go

@@ -14,21 +14,23 @@ import (
 // stats concerning the files and folders found. Select is used to decide which
 // items should be included. Error is called when an error occurs.
 type Scanner struct {
-	FS           fs.FS
-	SelectByName SelectByNameFunc
-	Select       SelectFunc
-	Error        ErrorFunc
-	Result       func(item string, s ScanStats)
+	FS             fs.FS
+	SelectByName   SelectByNameFunc
+	Select         SelectFunc
+	Error          ErrorFunc
+	Result         func(item string, s ScanStats)
+	FollowSymLinks bool
 }
 
 // NewScanner initializes a new Scanner.
 func NewScanner(fs fs.FS) *Scanner {
 	return &Scanner{
-		FS:           fs,
-		SelectByName: func(item string) bool { return true },
-		Select:       func(item string, fi os.FileInfo) bool { return true },
-		Error:        func(item string, err error) error { return err },
-		Result:       func(item string, s ScanStats) {},
+		FS:             fs,
+		SelectByName:   func(item string) bool { return true },
+		Select:         func(item string, fi os.FileInfo) bool { return true },
+		Error:          func(item string, err error) error { return err },
+		Result:         func(item string, s ScanStats) {},
+		FollowSymLinks: false,
 	}
 }
 
@@ -109,7 +111,13 @@ func (s *Scanner) scan(ctx context.Context, stats ScanStats, target string) (Sca
 	}
 
 	// get file information
-	fi, err := s.FS.Lstat(target)
+	var fi os.FileInfo
+	var err error
+	if s.FollowSymLinks {
+		fi, err = s.FS.Stat(target)
+	} else {
+		fi, err = s.FS.Lstat(target)
+	}
 	if err != nil {
 		return stats, s.Error(target, err)
 	}