3 BUGS ---------------------------------------------------------------
5 rsync-url barfs on upload
7 rsync foo rsync://localhost/transfer/
12 There seems to be a bug with hardlinks
14 mbp/2 build$ ls -l /tmp/a /tmp/b -i
17 2568307 -rw-rw-r-- 3 mbp mbp 29 Mar 25 17:30 a1
18 2568307 -rw-rw-r-- 3 mbp mbp 29 Mar 25 17:30 a2
19 2568307 -rw-rw-r-- 3 mbp mbp 29 Mar 25 17:30 a3
20 2568310 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 a4
21 2568310 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 a5
22 2568310 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 b1
23 2568310 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 b2
24 2568310 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 b3
28 2568309 -rw-rw-r-- 3 mbp mbp 29 Mar 25 17:30 a1
29 2568309 -rw-rw-r-- 3 mbp mbp 29 Mar 25 17:30 a2
30 2568309 -rw-rw-r-- 3 mbp mbp 29 Mar 25 17:30 a3
31 2568311 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 a4
32 2568311 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 a5
33 2568311 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 b1
34 2568311 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 b2
35 2568311 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 b3
36 mbp/2 build$ rm -r /tmp/b && ./rsync -avH /tmp/a/ /tmp/b
37 building file list ... done
38 created directory /tmp/b
44 wrote 350 bytes read 52 bytes 804.00 bytes/sec
45 total size is 232 speedup is 0.58
46 mbp/2 build$ rm -r /tmp/b
47 mbp/2 build$ ls -l /tmp/b
48 ls: /tmp/b: No such file or directory
49 mbp/2 build$ rm -r /tmp/b && ./rsync -avH /tmp/a/ /tmp/b
50 rm: cannot remove `/tmp/b': No such file or directory
51 mbp/2 build$ rm -f -r /tmp/b && ./rsync -avH /tmp/a/ /tmp/b
52 building file list ... done
53 created directory /tmp/b
59 wrote 350 bytes read 52 bytes 804.00 bytes/sec
60 total size is 232 speedup is 0.58
61 mbp/2 build$ ls -l /tmp/b
63 -rw-rw-r-- 3 mbp mbp 29 Mar 25 17:30 a1
64 -rw-rw-r-- 3 mbp mbp 29 Mar 25 17:30 a2
65 -rw-rw-r-- 3 mbp mbp 29 Mar 25 17:30 a3
66 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 a4
67 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 a5
68 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 b1
69 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 b2
70 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 b3
71 mbp/2 build$ ls -l /tmp/a
73 -rw-rw-r-- 3 mbp mbp 29 Mar 25 17:30 a1
74 -rw-rw-r-- 3 mbp mbp 29 Mar 25 17:30 a2
75 -rw-rw-r-- 3 mbp mbp 29 Mar 25 17:30 a3
76 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 a4
77 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 a5
78 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 b1
79 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 b2
80 -rw-rw-r-- 5 mbp mbp 29 Mar 25 17:30 b3
83 Progress indicator can produce corrupt output when transferring directories:
86 main/binary-arm/admin/
88 main/binary-arm/comm/8.56kB/s 0:00:52
89 main/binary-arm/devel/
91 main/binary-arm/editors/
92 main/binary-arm/electronics/s 0:00:53
93 main/binary-arm/games/
94 main/binary-arm/graphics/
95 main/binary-arm/hamradio/
96 main/binary-arm/interpreters/
97 main/binary-arm/libs/6.61kB/s 0:00:54
100 main/binary-arm/misc/
103 I don't think we handle this properly on systems that don't have the
107 Part of the regression suite should be making sure that we don't
108 break backwards compatibility: old clients vs new servers and so
109 on. Ideally we would test the cross product of versions.
111 It might be sufficient to test downloads from well-known public
112 rsync servers running different versions of rsync. This will give
113 some testing and also be the most common case for having different
114 versions and not being able to upgrade.
116 --no-blocking-io might be broken
118 in the same way as --no-whole-file; somebody needs to check.
121 DAEMON --------------------------------------------------------------
123 server-imposed bandwidth limits
127 There are already some patches to do this.
129 BitKeeper uses a server whose login shell is set to bkd. That's
130 probably a reasonable approach.
133 FEATURES ------------------------------------------------------------
136 --dry-run is insufficiently dry
138 Mark Santcroos points out that -n fails to list files which have
139 only metadata changes, though it probably should.
141 There may be a Debian bug about this as well.
146 If the platform doesn't support it, then don't even try.
148 If running as non-root, then don't fail, just give a warning.
149 (There was a thread about this a while ago?)
151 http://lists.samba.org/pipermail/rsync/2001-August/thread.html
152 http://lists.samba.org/pipermail/rsync/2001-September/thread.html
157 Avoids traversal. Better option than a pile of --include statements
158 for people who want to generate the file list using a find(1)
164 Perhaps allow supplementary groups to be specified in rsyncd.conf;
165 then make the first one the primary gid and all the rest be
169 File list structure in memory
171 Rather than one big array, perhaps have a tree in memory mirroring
174 This might make sorting much faster! (I'm not sure it's a big CPU
177 It might also reduce memory use in storing repeated directory names
178 -- again I'm not sure this is a problem.
182 Traverse just one directory at a time. Tridge says it's possible.
184 At the moment rsync reads the whole file list into memory at the
185 start, which makes us use a lot of memory and also not pipeline
186 network access as much as we could.
189 Handling duplicate names
191 We need to be careful of duplicate names getting into the file list.
192 See clean_flist(). This could happen if multiple arguments include
195 I think duplicates are only a problem if they're both flowing
196 through the pipeline at the same time. For example we might have
197 updated the first occurrence after reading the checksums for the
198 second. So possibly we just need to make sure that we don't have
199 both in the pipeline at the same time.
201 Possibly if we did one directory at a time that would be sufficient.
203 Alternatively we could pre-process the arguments to make sure no
204 duplicates will ever be inserted. There could be some bad cases
205 when we're collapsing symlinks.
207 We could have a hash table.
209 The root of the problem is that we do not want more than one file
210 list entry referring to the same file. At first glance there are
211 several ways this could happen: symlinks, hardlinks, and repeated
212 names on the command line.
214 If names are repeated on the command line, they may be present in
215 different forms, perhaps by traversing directory paths in different
216 ways, traversing paths including symlinks. Also we need to allow
217 for expansion of globs by rsync.
219 At the moment, clean_flist() requires having the entire file list in
220 memory. Duplicate names are detected just by a string comparison.
222 We don't need to worry about hard links causing duplicates because
223 files are never updated in place. Similarly for symlinks.
225 I think even if we're using a different symlink mode we don't need
228 Unless we're really clever this will introduce a protocol
229 incompatibility, so we need to be able to accept the old format as
235 At exit, show how much memory was used for the file list, etc.
237 Also we do a wierd exponential-growth allocation in flist.c. I'm
238 not sure this makes sense with modern mallocs. At any rate it will
239 make us allocate a huge amount of memory for large file lists.
244 At the moment hardlink handling is very expensive, so it's off by
245 default. It does not need to be so.
247 Since most of the solutions are rather intertwined with the file
248 list it is probably better to fix that first, although fixing
249 hardlinks is possibly simpler.
251 We can rule out hardlinked directories since they will probably
252 screw us up in all kinds of ways. They simply should not be used.
254 At the moment rsync only cares about hardlinks to regular files. I
255 guess you could also use them for sockets, devices and other beasts,
256 but I have not seen them.
258 When trying to reproduce hard links, we only need to worry about
259 files that have more than one name (nlinks>1 && !S_ISDIR).
261 The basic point of this is to discover alternate names that refer to
262 the same file. All operations, including creating the file and
263 writing modifications to it need only to be done for the first name.
264 For all later names, we just create the link and then leave it
267 If hard links are to be preserved:
269 Before the generator/receiver fork, the list of files is received
270 from the sender (recv_file_list), and a table for detecting hard
273 The generator looks for hard links within the file list and does
274 not send checksums for them, though it does send other metadata.
276 The sender sends the device number and inode with file entries, so
277 that files are uniquely identified.
279 The receiver goes through and creates hard links (do_hard_links)
280 after all data has been written, but before directory permissions
283 At the moment device and inum are sent as 4-byte integers, which
284 will probably cause problems on large filesystems. On Linux the
285 kernel uses 64-bit ino_t's internally, and people will soon have
286 filesystems big enough to use them. We ought to follow NFS4 in
287 using 64-bit device and inode identification, perhaps with a
288 protocol version bump.
290 Once we've seen all the names for a particular file, we no longer
291 need to think about it and we can deallocate the memory.
293 We can also have the case where there are links to a file that are
294 not in the tree being transferred. There's nothing we can do about
295 that. Because we rename the destination into place after writing,
296 any hardlinks to the old file are always going to be orphaned. In
297 fact that is almost necessary because otherwise we'd get really
298 confused if we were generating checksums for one name of a file and
301 At the moment the code seems to make a whole second copy of the file
302 list, which seems unnecessary.
304 We should have a test case that exercises hard links. Since it
305 might be hard to compare ./tls output where the inodes change we
306 might need a little program to check whether several names refer to
311 Implement suggestions from http://www.kame.net/newsletter/19980604/
312 and ftp://ftp.iij.ad.jp/pub/RFC/rfc2553.txt
314 If a host has multiple addresses, then listen try to connect to all
315 in order until we get through. (getaddrinfo may return multiple
316 addresses.) This is kind of implemented already.
318 Possibly also when starting as a server we may need to listen on
319 multiple passive addresses. This might be a bit harder, because we
320 may need to select on all of them. Hm.
322 Define a syntax for IPv6 literal addresses. Since they include
323 colons, they tend to break most naming systems, including ours.
324 Based on the HTTP IPv6 syntax, I think we should use
326 rsync://[::1]/foo/bar
329 which should just take a small change to the parser code.
334 If we hang or get SIGINT, then explain where we were up to. Perhaps
335 have a static buffer that contains the current function name, or
336 some kind of description of what we were trying to do. This is a
337 little easier on people than needing to run strace/truss.
339 "The dungeon collapses! You are killed." Rather than "unexpected
340 eof" give a message that is more detailed if possible and also more
343 If we get an error writing to a socket, then we should perhaps
344 continue trying to read to see if an error message comes across
345 explaining why the socket is closed. I'm not sure if this would
346 work, but it would certainly make our messages more helpful.
348 What happens if a directory is missing -x attributes. Do we lose
349 our load? (Debian #28416) Probably fixed now, but a test case
355 Device major/minor numbers should be at least 32 bits each. See
356 http://lists.samba.org/pipermail/rsync/2001-November/005357.html
358 Transfer ACLs. Need to think of a standard representation.
359 Probably better not to even try to convert between NT and POSIX.
360 Possibly can share some code with Samba.
364 With the current common --include '*/' --exclude '*' pattern, people
365 can end up with many empty directories. We might avoid this by
366 lazily creating such directories.
371 Perhaps don't use our own zlib.
375 - will automatically be up to date with bugfixes in zlib
377 - can leave it out for small rsync on e.g. recovery disks
379 - can use a shared library
381 - avoids people breaking rsync by trying to do this themselves and
384 Should we ship zlib for systems that don't have it, or require
385 people to install it separately?
387 Apparently this will make us incompatible with versions of rsync
388 that use the patched version of rsync. Probably the simplest way to
389 do this is to just disable gzip (with a warning) when talking to old
395 Perhaps flush stdout after each filename, so that people trying to
396 monitor progress in a log file can do so more easily. See
397 http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=48108
399 At the connections that just get a list of modules are not logged,
402 If a child of the rsync daemon dies with a signal, we should notice
403 that when we reap it and log a message.
405 Keep stderr and stdout properly separated (Debian #23626)
407 After we get the @RSYNCD greeting from the server, we know it's
408 version but we have not yet sent the command line, so we could just
409 remove the -z option if the server is too old.
411 For ssh invocation it's not so simple, because we actually use the
412 command line to start the remote process. However, we only actually
413 do compression in token.c, and we could therefore once we discover
414 the remote version emit an error if it's too old. I'm not sure if
415 that's a good tradeoff or not.
420 There are already some patches to do this.
424 Allow RSYNC_PROXY to be http://user:pass@proxy.foo:3128/, and do
425 HTTP Basic Proxy-Authentication.
427 Multiple schemes are possible, up to and including the insanity that
428 is NTLM, but Basic probably covers most cases.
432 Add --with-socks, and then perhaps a command-line option to put them
433 on or off. This might be more reliable than LD_PRELOAD hacks.
437 rsync to a FAT partition on a Unix machine doesn't work very well
438 at the moment. I think we get errors about invalid filenames and
439 perhaps also trying to do atomic renames.
441 I guess the code to do this is currently #ifdef'd on Windows; perhaps
442 we ought to intelligently fall back to it on Unix too.
447 <Rasmus> mbp: hey, how about an rsync option that just gives you the
448 summary without the list of files? And perhaps gives more
449 information like the number of new files, number of changed,
451 <mbp> Rasmus: nice idea
452 <mbp> there is --stats
453 <mbp> but at the moment it's very tridge-oriented
454 <mbp> rather than user-friendly
455 <mbp> it would be nice to improve it
456 <mbp> that would also work well with --dryrun
460 Rather than storing the file list in memory, store it in a TDB.
462 This *might* make memory usage lower while building the file list.
464 Hashtable lookup will mean files are not transmitted in order,
467 This would neatly eliminate one of the major post-fork shared data
473 On 12 Mar 2002, Dave Dykstra <dwd@bell-labs.com> wrote:
474 > If we would add an option to do that functionality, I would vote for one
475 > that was more general which could mask off any set of permission bits and
476 > possibly add any set of bits. Perhaps a chmod-like syntax if it could be
477 > implemented simply.
479 I think that would be good too. For example, people uploading files
480 to a web server might like to say
482 rsync -avzP --chmod a+rX ./ sourcefrog.net:/home/www/sourcefrog/
484 Ideally the patch would implement as many of the gnu chmod semantics
485 as possible. I think the mode parser should be a separate function
486 that passes back something like (mask,set) description to the rest of
487 the program. For bonus points there would be a test case for the
495 Allow people to specify the diff command. (Might want to use wdiff,
498 Just diff the temporary file with the destination file, and delete
499 the tmp file rather than moving it into place.
501 Interaction with --partial.
503 Security interactions with daemon mode?
505 (Suggestion from david.e.sewell)
508 Incorrect timestamps (Debian #100295)
510 A bit hard to believe, but apparently it happens.
513 Check "refuse options works"
515 We need a test case for this...
517 Was this broken when we changed to popt?
520 PERFORMANCE ----------------------------------------------------------
524 If we're doing a local transfer, or using -W, then perhaps don't
525 send the file checksum. If we're doing a local transfer, then
526 calculating MD4 checksums uses 90% of CPU and is unlikely to be
529 Indeed for transfers over zlib or ssh we can also rely on the
530 transport to have quite strong protection against corruption.
532 Perhaps we should have an option to disable this, analogous to
533 --whole-file, although it would default to disabled. The file
534 checksum takes up a definite space in the protocol -- we can either
535 set it to 0, or perhaps just leave it out.
539 Perhaps borrow an assembler MD4 from someone?
541 Make sure we call MD4 with properly-sized blocks whenever possible
542 to avoid copying into the residue region?
546 Test whether this is actually faster than just using malloc(). If
547 it's not (anymore), throw it out.
550 PLATFORMS ------------------------------------------------------------
554 Don't detach, because this messes up --srvany.
556 http://sources.redhat.com/ml/cygwin/2001-08/msg00234.html
558 According to "Effective TCP/IP Programming" (??) close() on a socket
559 has incorrect behaviour on Windows -- it sends a RST packet to the
560 other side, which gives a "connection reset by peer" error. On that
561 platform we should probably do shutdown() instead. However, on Unix
562 we are correct to call close(), because shutdown() discards
566 DEVELOPMENT ----------------------------------------------------------
570 Build rsync with SPLINT to try to find security holes. Add
571 annotations as necessary. Keep track of the number of warnings
572 found initially, and see how many of them are real bugs, or real
573 security bugs. Knowing the percentage of likely hits would be
574 really interesting for other projects.
578 Something that just keeps running rsync continuously over a data set
579 likely to generate problems.
583 Run current rsync versions against significant past releases.
587 jra recommends Valgrind:
589 http://devel-home.kde.org/~sewardj/
595 Build tar file; upload
597 Send announcement to mailing list and c.o.l.a.
599 Make freshmeat announcement
605 TESTING --------------------------------------------------------------
609 Part of the regression suite should be making sure that we don't
610 break backwards compatibility: old clients vs new servers and so
611 on. Ideally we would test both up and down from the current release
614 We might need to omit broken old versions, or versions in which
615 particular functionality is broken
617 It might be sufficient to test downloads from well-known public
618 rsync servers running different versions of rsync. This will give
619 some testing and also be the most common case for having different
620 versions and not being able to upgrade.
623 Test on kernel source
625 Download all versions of kernel; unpack, sync between them. Also
626 sync between uncompressed tarballs. Compare directories after
629 Use local mode; ssh; daemon; --whole-file and --no-whole-file.
631 Use awk to pull out the 'speedup' number for each transfer. Make
637 Sparse and non-sparse
641 Insert bytes, delete bytes, swap blocks, ...
643 configure option to enable dangerous tests
645 If tests are skipped, say why.
647 Test daemon feature to disallow particular options.
649 Pipe program that makes slow/jerky connections.
651 Versions of read() and write() that corrupt the stream, or abruptly fail
653 Separate makefile target to run rough tests -- or perhaps just run
656 Test "refuse options" works
658 What about for --recursive?
660 If you specify an unrecognized option here, you should get an error.
663 DOCUMENTATION --------------------------------------------------------
667 Keep list of open issues and todos on the web site
669 Update web site from CVS
672 Perhaps redo manual as SGML
674 The man page is getting rather large, and there is more information
675 that ought to be added.
677 TexInfo source is probably a dying format.
679 Linuxdoc looks like the most likely contender. I know DocBook is
680 favoured by some people, but it's so bloody verbose, even with emacs
684 BUILD FARM -----------------------------------------------------------
688 AMDAHL UTS (Dave Dykstra)
690 Cygwin (on different versions of Win32?)
692 HP-UX variants (via HP?)
697 LOGGING --------------------------------------------------------------
699 Perhaps flush stdout after each filename, so that people trying to
700 monitor progress in a log file can do so more easily. See
701 http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=48108
703 At the connections that just get a list of modules are not logged,
706 If a child of the rsync daemon dies with a signal, we should notice
707 that when we reap it and log a message.
709 Keep stderr and stdout properly separated (Debian #23626)
711 Use a separate function for reporting errors; prefix it with
712 "rsync:" or "rsync(remote)", or perhaps even "rsync(local
717 Indicate whether files are new, updated, or deleted
719 At end of transfer, show how many files were or were not transferred
724 Explain *why* every file is transferred or not (e.g. "local mtime
725 123123 newer than 1283198")
730 Add an rsyncd.conf parameter to turn on debugging on the server.
734 NICE -----------------------------------------------------------------
736 --no-detach and --no-fork options
738 Very useful for debugging. Also good when running under a
739 daemon-monitoring process that tries to restart the service when the
742 hang/timeout friendliness
746 Change to using gettext(). Probably need to ship this for platforms
749 Solicit translations.
751 Does anyone care? Before we bother modifying the code, we ought to
752 get the manual translated first, because that's possibly more useful
753 and at any rate demonstrates desire.
757 Write a small emulation of interactive ftp as a Pythonn program
758 that calls rsync. Commands such as "cd", "ls", "ls *.c" etc map
759 fairly directly into rsync commands: it just needs to remember the
760 current host, directory and so on. We can probably even do
761 completion of remote filenames.
764 RELATED PROJECTS -----------------------------------------------------
766 http://rsync.samba.org/rsync-and-debian/
770 Exhaustive, tortuous testing
774 rsyncsplit as alternative to real integration with gzip?
776 reverse rsync over HTTP Range
778 Goswin Brederlow suggested this on Debian; I think tridge and I
779 talked about it previous in relation to rproxy.