rclone/cmd/bisync/deltas.go
nielash 422b037087 bisync: fallback to cryptcheck or --download when can't check hash
Bisync checks file equality before renaming sync conflicts by comparing
checksums. Before this change, backends without checksum support (notably
Crypt) would fall back to --size-only for these checks, which is not a very
safe method (differing files can sometimes have the same size, especially if
they're small.) After this change, Crypt remotes fallback to using Cryptcheck
so that checksums can be compared. As a last resort when neither Check nor
Cryptcheck are available, files are compared using --download so that we can be
certain the files are identical regardless of checksum support.
2024-01-20 14:50:08 -05:00

526 lines
14 KiB
Go

// Package bisync implements bisync
// Copyright (c) 2017-2020 Chris Nelson
package bisync
import (
"context"
"fmt"
"path/filepath"
"sort"
"strings"
"github.com/rclone/rclone/cmd/bisync/bilib"
"github.com/rclone/rclone/fs"
"github.com/rclone/rclone/fs/filter"
"github.com/rclone/rclone/fs/operations"
"golang.org/x/text/unicode/norm"
)
// delta
type delta uint8
const (
deltaZero delta = 0
deltaNew delta = 1 << iota
deltaNewer
deltaOlder
deltaSize
deltaHash
deltaDeleted
)
const (
deltaModified delta = deltaNewer | deltaOlder | deltaSize | deltaHash | deltaDeleted
deltaOther delta = deltaNew | deltaNewer | deltaOlder
)
func (d delta) is(cond delta) bool {
return d&cond != 0
}
// deltaSet
type deltaSet struct {
deltas map[string]delta
opt *Options
fs fs.Fs // base filesystem
msg string // filesystem name for logging
oldCount int // original number of files (for "excess deletes" check)
deleted int // number of deleted files (for "excess deletes" check)
foundSame bool // true if found at least one unchanged file
checkFiles bilib.Names
}
func (ds *deltaSet) empty() bool {
return len(ds.deltas) == 0
}
func (ds *deltaSet) sort() (sorted []string) {
if ds.empty() {
return
}
sorted = make([]string, 0, len(ds.deltas))
for file := range ds.deltas {
sorted = append(sorted, file)
}
sort.Strings(sorted)
return
}
func (ds *deltaSet) printStats() {
if ds.empty() {
return
}
nAll := len(ds.deltas)
nNew := 0
nNewer := 0
nOlder := 0
nDeleted := 0
for _, d := range ds.deltas {
if d.is(deltaNew) {
nNew++
}
if d.is(deltaNewer) {
nNewer++
}
if d.is(deltaOlder) {
nOlder++
}
if d.is(deltaDeleted) {
nDeleted++
}
}
fs.Infof(nil, "%s: %4d changes: %4d new, %4d newer, %4d older, %4d deleted",
ds.msg, nAll, nNew, nNewer, nOlder, nDeleted)
}
// findDeltas
func (b *bisyncRun) findDeltas(fctx context.Context, f fs.Fs, oldListing string, now *fileList, msg string) (ds *deltaSet, err error) {
var old *fileList
newListing := oldListing + "-new"
old, err = b.loadListing(oldListing)
if err != nil {
fs.Errorf(nil, "Failed loading prior %s listing: %s", msg, oldListing)
b.abort = true
return
}
if err = b.checkListing(old, oldListing, "prior "+msg); err != nil {
return
}
if err == nil {
err = b.checkListing(now, newListing, "current "+msg)
}
if err != nil {
return
}
ds = &deltaSet{
deltas: map[string]delta{},
fs: f,
msg: msg,
oldCount: len(old.list),
opt: b.opt,
checkFiles: bilib.Names{},
}
for _, file := range old.list {
d := deltaZero
if !now.has(file) {
b.indent(msg, file, "File was deleted")
ds.deleted++
d |= deltaDeleted
} else {
// skip dirs here, as we only care if they are new/deleted, not newer/older
if !now.isDir(file) {
if old.getTime(file) != now.getTime(file) {
if old.beforeOther(now, file) {
fs.Debugf(file, "(old: %v current: %v", old.getTime(file), now.getTime(file))
b.indent(msg, file, "File is newer")
d |= deltaNewer
} else { // Current version is older than prior sync.
fs.Debugf(file, "(old: %v current: %v", old.getTime(file), now.getTime(file))
b.indent(msg, file, "File is OLDER")
d |= deltaOlder
}
}
// TODO Compare sizes and hashes
}
}
if d.is(deltaModified) {
ds.deltas[file] = d
} else {
// Once we've found at least one unchanged file,
// we know that not everything has changed,
// as with a DST time change
ds.foundSame = true
}
}
for _, file := range now.list {
if !old.has(file) {
b.indent(msg, file, "File is new")
ds.deltas[file] = deltaNew
}
}
if b.opt.CheckAccess {
// checkFiles is a small structure compared with the `now`, so we
// return it alone and let the full delta map be garbage collected.
for _, file := range now.list {
if filepath.Base(file) == b.opt.CheckFilename {
ds.checkFiles.Add(file)
}
}
}
return
}
// applyDeltas
func (b *bisyncRun) applyDeltas(ctx context.Context, ds1, ds2 *deltaSet) (changes1, changes2 bool, results2to1, results1to2 []Results, queues queues, err error) {
path1 := bilib.FsPath(b.fs1)
path2 := bilib.FsPath(b.fs2)
copy1to2 := bilib.Names{}
copy2to1 := bilib.Names{}
delete1 := bilib.Names{}
delete2 := bilib.Names{}
handled := bilib.Names{}
renamed1 := bilib.Names{}
renamed2 := bilib.Names{}
renameSkipped := bilib.Names{}
deletedonboth := bilib.Names{}
skippedDirs1 := newFileList()
skippedDirs2 := newFileList()
ctxMove := b.opt.setDryRun(ctx)
// update AliasMap for deleted files, as march does not know about them
b.updateAliases(ctx, ds1, ds2)
// efficient isDir check
// we load the listing just once and store only the dirs
dirs1, dirs1Err := b.listDirsOnly(1)
if dirs1Err != nil {
b.critical = true
b.retryable = true
fs.Debugf(nil, "Error generating dirsonly list for path1: %v", dirs1Err)
return
}
dirs2, dirs2Err := b.listDirsOnly(2)
if dirs2Err != nil {
b.critical = true
b.retryable = true
fs.Debugf(nil, "Error generating dirsonly list for path2: %v", dirs2Err)
return
}
// build a list of only the "deltaOther"s so we don't have to check more files than necessary
// this is essentially the same as running rclone check with a --files-from filter, then exempting the --match results from being renamed
// we therefore avoid having to list the same directory more than once.
// we are intentionally overriding DryRun here because we need to perform the check, even during a dry run, or the results would be inaccurate.
// check is a read-only operation by its nature, so it's already "dry" in that sense.
ctxNew, ciCheck := fs.AddConfig(ctx)
ciCheck.DryRun = false
ctxCheck, filterCheck := filter.AddConfig(ctxNew)
for _, file := range ds1.sort() {
alias := b.aliases.Alias(file)
d1 := ds1.deltas[file]
if d1.is(deltaOther) {
d2, in2 := ds2.deltas[file]
if !in2 && file != alias {
d2 = ds2.deltas[alias]
}
if d2.is(deltaOther) {
checkit := func(filename string) {
if err := filterCheck.AddFile(filename); err != nil {
fs.Debugf(nil, "Non-critical error adding file to list of potential conflicts to check: %s", err)
} else {
fs.Debugf(nil, "Added file to list of potential conflicts to check: %s", filename)
}
}
checkit(file)
if file != alias {
checkit(alias)
}
}
}
}
//if there are potential conflicts to check, check them all here (outside the loop) in one fell swoop
matches, err := b.checkconflicts(ctxCheck, filterCheck, b.fs1, b.fs2)
for _, file := range ds1.sort() {
alias := b.aliases.Alias(file)
p1 := path1 + file
p2 := path2 + alias
d1 := ds1.deltas[file]
if d1.is(deltaOther) {
d2, in2 := ds2.deltas[file]
// try looking under alternate name
if !in2 && file != alias {
d2, in2 = ds2.deltas[alias]
}
if !in2 {
b.indent("Path1", p2, "Queue copy to Path2")
copy1to2.Add(file)
} else if d2.is(deltaDeleted) {
b.indent("Path1", p2, "Queue copy to Path2")
copy1to2.Add(file)
handled.Add(file)
} else if d2.is(deltaOther) {
b.indent("!WARNING", file, "New or changed in both paths")
//if files are identical, leave them alone instead of renaming
if (dirs1.has(file) || dirs1.has(alias)) && (dirs2.has(file) || dirs2.has(alias)) {
fs.Debugf(nil, "This is a directory, not a file. Skipping equality check and will not rename: %s", file)
ls1.getPut(file, skippedDirs1)
ls2.getPut(file, skippedDirs2)
} else {
equal := matches.Has(file)
if !equal {
equal = matches.Has(alias)
}
if equal {
if ciCheck.FixCase && file != alias {
// the content is equal but filename still needs to be FixCase'd, so copy1to2
// the Path1 version is deemed "correct" in this scenario
fs.Infof(alias, "Files are equal but will copy anyway to fix case to %s", file)
copy1to2.Add(file)
} else {
fs.Infof(nil, "Files are equal! Skipping: %s", file)
renameSkipped.Add(file)
renameSkipped.Add(alias)
}
} else {
fs.Debugf(nil, "Files are NOT equal: %s", file)
b.indent("!Path1", p1+"..path1", "Renaming Path1 copy")
ctxMove = b.setBackupDir(ctxMove, 1) // in case already a file with new name
if err = operations.MoveFile(ctxMove, b.fs1, b.fs1, file+"..path1", file); err != nil {
err = fmt.Errorf("path1 rename failed for %s: %w", p1, err)
b.critical = true
return
}
if b.opt.DryRun {
renameSkipped.Add(file)
} else {
renamed1.Add(file)
}
b.indent("!Path1", p2+"..path1", "Queue copy to Path2")
copy1to2.Add(file + "..path1")
b.indent("!Path2", p2+"..path2", "Renaming Path2 copy")
ctxMove = b.setBackupDir(ctxMove, 2) // in case already a file with new name
if err = operations.MoveFile(ctxMove, b.fs2, b.fs2, alias+"..path2", alias); err != nil {
err = fmt.Errorf("path2 rename failed for %s: %w", alias, err)
return
}
if b.opt.DryRun {
renameSkipped.Add(alias)
} else {
renamed2.Add(alias)
}
b.indent("!Path2", p1+"..path2", "Queue copy to Path1")
copy2to1.Add(alias + "..path2")
}
}
handled.Add(file)
}
} else {
// Path1 deleted
d2, in2 := ds2.deltas[file]
// try looking under alternate name
fs.Debugf(file, "alias: %s, in2: %v", alias, in2)
if !in2 && file != alias {
fs.Debugf(file, "looking for alias: %s", alias)
d2, in2 = ds2.deltas[alias]
if in2 {
fs.Debugf(file, "detected alias: %s", alias)
}
}
if !in2 {
b.indent("Path2", p2, "Queue delete")
delete2.Add(file)
copy1to2.Add(file)
} else if d2.is(deltaOther) {
b.indent("Path2", p1, "Queue copy to Path1")
copy2to1.Add(file)
handled.Add(file)
} else if d2.is(deltaDeleted) {
handled.Add(file)
deletedonboth.Add(file)
deletedonboth.Add(alias)
}
}
}
for _, file := range ds2.sort() {
alias := b.aliases.Alias(file)
p1 := path1 + alias
d2 := ds2.deltas[file]
if handled.Has(file) || handled.Has(alias) {
continue
}
if d2.is(deltaOther) {
b.indent("Path2", p1, "Queue copy to Path1")
copy2to1.Add(file)
} else {
// Deleted
b.indent("Path1", p1, "Queue delete")
delete1.Add(file)
copy2to1.Add(file)
}
}
// Do the batch operation
if copy2to1.NotEmpty() {
changes1 = true
b.indent("Path2", "Path1", "Do queued copies to")
ctx = b.setBackupDir(ctx, 1)
results2to1, err = b.fastCopy(ctx, b.fs2, b.fs1, copy2to1, "copy2to1")
// retries, if any
results2to1, err = b.retryFastCopy(ctx, b.fs2, b.fs1, copy2to1, "copy2to1", results2to1, err)
if err != nil {
return
}
//copy empty dirs from path2 to path1 (if --create-empty-src-dirs)
b.syncEmptyDirs(ctx, b.fs1, copy2to1, dirs2, &results2to1, "make")
}
if copy1to2.NotEmpty() {
changes2 = true
b.indent("Path1", "Path2", "Do queued copies to")
ctx = b.setBackupDir(ctx, 2)
results1to2, err = b.fastCopy(ctx, b.fs1, b.fs2, copy1to2, "copy1to2")
// retries, if any
results1to2, err = b.retryFastCopy(ctx, b.fs1, b.fs2, copy1to2, "copy1to2", results1to2, err)
if err != nil {
return
}
//copy empty dirs from path1 to path2 (if --create-empty-src-dirs)
b.syncEmptyDirs(ctx, b.fs2, copy1to2, dirs1, &results1to2, "make")
}
if delete1.NotEmpty() {
if err = b.saveQueue(delete1, "delete1"); err != nil {
return
}
//propagate deletions of empty dirs from path2 to path1 (if --create-empty-src-dirs)
b.syncEmptyDirs(ctx, b.fs1, delete1, dirs1, &results2to1, "remove")
}
if delete2.NotEmpty() {
if err = b.saveQueue(delete2, "delete2"); err != nil {
return
}
//propagate deletions of empty dirs from path1 to path2 (if --create-empty-src-dirs)
b.syncEmptyDirs(ctx, b.fs2, delete2, dirs2, &results1to2, "remove")
}
queues.copy1to2 = copy1to2
queues.copy2to1 = copy2to1
queues.renamed1 = renamed1
queues.renamed2 = renamed2
queues.renameSkipped = renameSkipped
queues.deletedonboth = deletedonboth
queues.skippedDirs1 = skippedDirs1
queues.skippedDirs2 = skippedDirs2
return
}
// excessDeletes checks whether number of deletes is within allowed range
func (ds *deltaSet) excessDeletes() bool {
maxDelete := ds.opt.MaxDelete
maxRatio := float64(maxDelete) / 100.0
curRatio := 0.0
if ds.deleted > 0 && ds.oldCount > 0 {
curRatio = float64(ds.deleted) / float64(ds.oldCount)
}
if curRatio <= maxRatio {
return false
}
fs.Errorf("Safety abort",
"too many deletes (>%d%%, %d of %d) on %s %s. Run with --force if desired.",
maxDelete, ds.deleted, ds.oldCount, ds.msg, quotePath(bilib.FsPath(ds.fs)))
return true
}
// normally we build the AliasMap from march results,
// however, march does not know about deleted files, so need to manually check them for aliases
func (b *bisyncRun) updateAliases(ctx context.Context, ds1, ds2 *deltaSet) {
ci := fs.GetConfig(ctx)
// skip if not needed
if ci.NoUnicodeNormalization && !ci.IgnoreCaseSync && !b.fs1.Features().CaseInsensitive && !b.fs2.Features().CaseInsensitive {
return
}
if ds1.deleted < 1 && ds2.deleted < 1 {
return
}
fs.Debugf(nil, "Updating AliasMap")
transform := func(s string) string {
if !ci.NoUnicodeNormalization {
s = norm.NFC.String(s)
}
// note: march only checks the dest, but we check both here
if ci.IgnoreCaseSync || b.fs1.Features().CaseInsensitive || b.fs2.Features().CaseInsensitive {
s = strings.ToLower(s)
}
return s
}
delMap1 := map[string]string{} // [transformedname]originalname
delMap2 := map[string]string{} // [transformedname]originalname
fullMap1 := map[string]string{} // [transformedname]originalname
fullMap2 := map[string]string{} // [transformedname]originalname
for _, name := range ls1.list {
fullMap1[transform(name)] = name
}
for _, name := range ls2.list {
fullMap2[transform(name)] = name
}
addDeletes := func(ds *deltaSet, delMap, fullMap map[string]string) {
for _, file := range ds.sort() {
d := ds.deltas[file]
if d.is(deltaDeleted) {
delMap[transform(file)] = file
fullMap[transform(file)] = file
}
}
}
addDeletes(ds1, delMap1, fullMap1)
addDeletes(ds2, delMap2, fullMap2)
addAliases := func(delMap, fullMap map[string]string) {
for transformedname, name := range delMap {
matchedName, found := fullMap[transformedname]
if found && name != matchedName {
fs.Debugf(name, "adding alias %s", matchedName)
b.aliases.Add(name, matchedName)
}
}
}
addAliases(delMap1, fullMap2)
addAliases(delMap2, fullMap1)
}