-*- indented-text -*- BUGS --------------------------------------------------------------- Fix progress indicator to not corrupt log lchmod question Do not rely on having a group called "nobody" Incorrect timestamps (Debian #100295) Win32 FEATURES ------------------------------------------------------------ server-imposed bandwidth limits rsyncd over ssh Use chroot only if supported Allow supplementary groups in rsyncd.conf 2002/04/09 Handling IPv6 on old machines Other IPv6 stuff: Add ACL support 2001/12/02 Lazy directory creation proxy authentication 2002/01/23 SOCKS 2002/01/23 FAT support Allow forcing arbitrary permissions 2002/03/12 --diff david.e.sewell 2002/03/15 Add daemon --no-fork option Create more granular verbosity jw 2003/05/15 DOCUMENTATION -------------------------------------------------------- Update README Keep list of open issues and todos on the web site Perhaps redo manual as SGML LOGGING -------------------------------------------------------------- Make dry run list all updates 2002/04/03 Memory accounting Improve error messages Better statistics: Rasmus 2002/03/08 Perhaps flush stdout like syslog Log deamon sessions that just list modules Log child death on signal Keep stderr and stdout properly separated (Debian #23626) Log errors with function that reports process of origin verbose output David Stein 2001/12/20 Add reason for transfer to file logging debugging of daemon 2002/04/08 internationalization DEVELOPMENT -------------------------------------------------------- Handling duplicate names Use generic zlib 2002/02/25 TDB: 2002/03/12 Splint 2002/03/12 Memory debugger Create release script Add machines to build farm PERFORMANCE ---------------------------------------------------------- File list structure in memory Traverse just one directory at a time Allow skipping MD4 file_sum 2002/04/08 Accelerate MD4 TESTING -------------------------------------------------------------- Torture test Cross-test versions 2001/08/22 Test on kernel source Test large files Create mutator program for testing Create configure option to enable dangerous tests If tests are skipped, say why. Test daemon feature to disallow particular options. Create pipe program for testing Create test makefile target for some tests RELATED PROJECTS ----------------------------------------------------- rsyncsh http://rsync.samba.org/rsync-and-debian/ rsyncable gzip patch rsyncsplit as alternative to real integration with gzip? reverse rsync over HTTP Range BUGS --------------------------------------------------------------- Fix progress indicator to not corrupt log Progress indicator can produce corrupt output when transferring directories: main/binary-arm/ main/binary-arm/admin/ main/binary-arm/base/ main/binary-arm/comm/8.56kB/s 0:00:52 main/binary-arm/devel/ main/binary-arm/doc/ main/binary-arm/editors/ main/binary-arm/electronics/s 0:00:53 main/binary-arm/games/ main/binary-arm/graphics/ main/binary-arm/hamradio/ main/binary-arm/interpreters/ main/binary-arm/libs/6.61kB/s 0:00:54 main/binary-arm/mail/ main/binary-arm/math/ main/binary-arm/misc/ -- -- lchmod question I don't think we handle this properly on systems that don't have the call. Are there any such? -- -- Do not rely on having a group called "nobody" http://www.linuxbase.org/spec/refspecs/LSB_1.1.0/gLSB/usernames.html On Debian it's "nogroup" -- -- Incorrect timestamps (Debian #100295) A bit hard to believe, but apparently it happens. -- -- Win32 Don't detach, because this messes up --srvany. http://sources.redhat.com/ml/cygwin/2001-08/msg00234.html -- -- FEATURES ------------------------------------------------------------ server-imposed bandwidth limits -- -- rsyncd over ssh There are already some patches to do this. BitKeeper uses a server whose login shell is set to bkd. That's probably a reasonable approach. -- -- Use chroot only if supported If the platform doesn't support it, then don't even try. If running as non-root, then don't fail, just give a warning. (There was a thread about this a while ago?) http://lists.samba.org/pipermail/rsync/2001-August/thread.html http://lists.samba.org/pipermail/rsync/2001-September/thread.html -- -- Allow supplementary groups in rsyncd.conf 2002/04/09 Perhaps allow supplementary groups to be specified in rsyncd.conf; then make the first one the primary gid and all the rest be supplementary gids. -- -- Handling IPv6 on old machines The KAME IPv6 patch is nice in theory but has proved a bit of a nightmare in practice. The basic idea of their patch is that rsync is rewritten to use the new getaddrinfo()/getnameinfo() interface, rather than gethostbyname()/gethostbyaddr() as in rsync 2.4.6. Systems that don't have the new interface are handled by providing our own implementation in lib/, which is selectively linked in. The problem with this is that it is really hard to get right on platforms that have a half-working implementation, so redefining these functions clashes with system headers, and leaving them out breaks. This affects at least OSF/1, RedHat 5, and Cobalt, which are moderately improtant. Perhaps the simplest solution would be to have two different files implementing the same interface, and choose either the new or the old API. This is probably necessary for systems that e.g. have IPv6, but gethostbyaddr() can't handle it. The Linux manpage claims this is currently the case. In fact, our internal sockets interface (things like open_socket_out(), etc) is much narrower than the getaddrinfo() interface, and so probably simpler to get right. In addition, the old code is known to work well on old machines. We could drop the rather large lib/getaddrinfo files. -- -- Other IPv6 stuff: Implement suggestions from http://www.kame.net/newsletter/19980604/ and ftp://ftp.iij.ad.jp/pub/RFC/rfc2553.txt If a host has multiple addresses, then listen try to connect to all in order until we get through. (getaddrinfo may return multiple addresses.) This is kind of implemented already. Possibly also when starting as a server we may need to listen on multiple passive addresses. This might be a bit harder, because we may need to select on all of them. Hm. Define a syntax for IPv6 literal addresses. Since they include colons, they tend to break most naming systems, including ours. Based on the HTTP IPv6 syntax, I think we should use rsync://[::1]/foo/bar [::1]::bar which should just take a small change to the parser code. -- -- Add ACL support 2001/12/02 Transfer ACLs. Need to think of a standard representation. Probably better not to even try to convert between NT and POSIX. Possibly can share some code with Samba. -- -- Lazy directory creation With the current common --include '*/' --exclude '*' pattern, people can end up with many empty directories. We might avoid this by lazily creating such directories. -- -- proxy authentication 2002/01/23 Allow RSYNC_PROXY to be http://user:pass@proxy.foo:3128/, and do HTTP Basic Proxy-Authentication. Multiple schemes are possible, up to and including the insanity that is NTLM, but Basic probably covers most cases. -- -- SOCKS 2002/01/23 Add --with-socks, and then perhaps a command-line option to put them on or off. This might be more reliable than LD_PRELOAD hacks. -- -- FAT support rsync to a FAT partition on a Unix machine doesn't work very well at the moment. I think we get errors about invalid filenames and perhaps also trying to do atomic renames. I guess the code to do this is currently #ifdef'd on Windows; perhaps we ought to intelligently fall back to it on Unix too. -- -- Allow forcing arbitrary permissions 2002/03/12 On 12 Mar 2002, Dave Dykstra wrote: > If we would add an option to do that functionality, I > would vote for one that was more general which could mask > off any set of permission bits and possibly add any set of > bits. Perhaps a chmod-like syntax if it could be > implemented simply. I think that would be good too. For example, people uploading files to a web server might like to say rsync -avzP --chmod a+rX ./ sourcefrog.net:/home/www/sourcefrog/ Ideally the patch would implement as many of the gnu chmod semantics as possible. I think the mode parser should be a separate function that passes back something like (mask,set) description to the rest of the program. For bonus points there would be a test case for the parser. Possibly also --chown (Debian #23628) -- -- --diff david.e.sewell 2002/03/15 Allow people to specify the diff command. (Might want to use wdiff, gnudiff, etc.) Just diff the temporary file with the destination file, and delete the tmp file rather than moving it into place. Interaction with --partial. Security interactions with daemon mode? -- -- Add daemon --no-fork option Very useful for debugging. Also good when running under a daemon-monitoring process that tries to restart the service when the parent exits. -- -- Create more granular verbosity jw 2003/05/15 Control output with the --report option. The option takes as a single argument (no whitespace) a comma delimited lists of keywords. This would separate debugging from "logging" as well as fine grained selection of statistical reporting and what actions are logged. http://lists.samba.org/archive/rsync/2003-May/006059.html -- -- DOCUMENTATION -------------------------------------------------------- Update README -- -- Keep list of open issues and todos on the web site -- -- Perhaps redo manual as SGML The man page is getting rather large, and there is more information that ought to be added. TexInfo source is probably a dying format. Linuxdoc looks like the most likely contender. I know DocBook is favoured by some people, but it's so bloody verbose, even with emacs support. -- -- LOGGING -------------------------------------------------------------- Make dry run list all updates 2002/04/03 --dry-run is too dry Mark Santcroos points out that -n fails to list files which have only metadata changes, though it probably should. There may be a Debian bug about this as well. -- -- Memory accounting At exit, show how much memory was used for the file list, etc. Also we do a wierd exponential-growth allocation in flist.c. I'm not sure this makes sense with modern mallocs. At any rate it will make us allocate a huge amount of memory for large file lists. -- -- Improve error messages If we hang or get SIGINT, then explain where we were up to. Perhaps have a static buffer that contains the current function name, or some kind of description of what we were trying to do. This is a little easier on people than needing to run strace/truss. "The dungeon collapses! You are killed." Rather than "unexpected eof" give a message that is more detailed if possible and also more helpful. If we get an error writing to a socket, then we should perhaps continue trying to read to see if an error message comes across explaining why the socket is closed. I'm not sure if this would work, but it would certainly make our messages more helpful. What happens if a directory is missing -x attributes. Do we lose our load? (Debian #28416) Probably fixed now, but a test case would be good. When running as a daemon, some errors should both be returned to the user and logged. This will make interacting with a daemon less cryptic. -- -- Better statistics: Rasmus 2002/03/08 hey, how about an rsync option that just gives you the summary without the list of files? And perhaps gives more information like the number of new files, number of changed, deleted, etc. ? nice idea there is --stats but at the moment it's very tridge-oriented rather than user-friendly it would be nice to improve it that would also work well with --dryrun -- -- Perhaps flush stdout like syslog Perhaps flush stdout after each filename, so that people trying to monitor progress in a log file can do so more easily. See http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=48108 -- -- Log deamon sessions that just list modules At the connections that just get a list of modules are not logged, but they should be. -- -- Log child death on signal If a child of the rsync daemon dies with a signal, we should notice that when we reap it and log a message. -- -- Keep stderr and stdout properly separated (Debian #23626) -- -- Log errors with function that reports process of origin Use a separate function for reporting errors; prefix it with "rsync:" or "rsync(remote)", or perhaps even "rsync(local generator): ". -- -- verbose output David Stein 2001/12/20 Indicate whether files are new, updated, or deleted At end of transfer, show how many files were or were not transferred correctly. -- -- Add reason for transfer to file logging Explain *why* every file is transferred or not (e.g. "local mtime 123123 newer than 1283198") -- -- debugging of daemon 2002/04/08 Add an rsyncd.conf parameter to turn on debugging on the server. -- -- internationalization Change to using gettext(). Probably need to ship this for platforms that don't have it. Solicit translations. Does anyone care? Before we bother modifying the code, we ought to get the manual translated first, because that's possibly more useful and at any rate demonstrates desire. -- -- DEVELOPMENT -------------------------------------------------------- Handling duplicate names We need to be careful of duplicate names getting into the file list. See clean_flist(). This could happen if multiple arguments include the same file. Bad. I think duplicates are only a problem if they're both flowing through the pipeline at the same time. For example we might have updated the first occurrence after reading the checksums for the second. So possibly we just need to make sure that we don't have both in the pipeline at the same time. Possibly if we did one directory at a time that would be sufficient. Alternatively we could pre-process the arguments to make sure no duplicates will ever be inserted. There could be some bad cases when we're collapsing symlinks. We could have a hash table. The root of the problem is that we do not want more than one file list entry referring to the same file. At first glance there are several ways this could happen: symlinks, hardlinks, and repeated names on the command line. If names are repeated on the command line, they may be present in different forms, perhaps by traversing directory paths in different ways, traversing paths including symlinks. Also we need to allow for expansion of globs by rsync. At the moment, clean_flist() requires having the entire file list in memory. Duplicate names are detected just by a string comparison. We don't need to worry about hard links causing duplicates because files are never updated in place. Similarly for symlinks. I think even if we're using a different symlink mode we don't need to worry. Unless we're really clever this will introduce a protocol incompatibility, so we need to be able to accept the old format as well. -- -- Use generic zlib 2002/02/25 Perhaps don't use our own zlib. Advantages: - will automatically be up to date with bugfixes in zlib - can leave it out for small rsync on e.g. recovery disks - can use a shared library - avoids people breaking rsync by trying to do this themselves and messing up Should we ship zlib for systems that don't have it, or require people to install it separately? Apparently this will make us incompatible with versions of rsync that use the patched version of rsync. Probably the simplest way to do this is to just disable gzip (with a warning) when talking to old versions. -- -- TDB: 2002/03/12 Rather than storing the file list in memory, store it in a TDB. This *might* make memory usage lower while building the file list. Hashtable lookup will mean files are not transmitted in order, though... hm. This would neatly eliminate one of the major post-fork shared data structures. -- -- Splint 2002/03/12 Build rsync with SPLINT to try to find security holes. Add annotations as necessary. Keep track of the number of warnings found initially, and see how many of them are real bugs, or real security bugs. Knowing the percentage of likely hits would be really interesting for other projects. -- -- Memory debugger jra recommends Valgrind: http://devel-home.kde.org/~sewardj/ -- -- Create release script Script would: Update spec files Build tar file; upload Send announcement to mailing list and c.o.l.a. Make freshmeat announcement Update web site -- -- Add machines to build farm Cygwin (on different versions of Win32?) HP-UX variants (via HP?) SCO -- -- PERFORMANCE ---------------------------------------------------------- File list structure in memory Rather than one big array, perhaps have a tree in memory mirroring the directory tree. This might make sorting much faster! (I'm not sure it's a big CPU problem, mind you.) It might also reduce memory use in storing repeated directory names -- again I'm not sure this is a problem. -- -- Traverse just one directory at a time Traverse just one directory at a time. Tridge says it's possible. At the moment rsync reads the whole file list into memory at the start, which makes us use a lot of memory and also not pipeline network access as much as we could. -- -- Allow skipping MD4 file_sum 2002/04/08 If we're doing a local transfer, or using -W, then perhaps don't send the file checksum. If we're doing a local transfer, then calculating MD4 checksums uses 90% of CPU and is unlikely to be useful. Indeed for transfers over zlib or ssh we can also rely on the transport to have quite strong protection against corruption. Perhaps we should have an option to disable this, analogous to --whole-file, although it would default to disabled. The file checksum takes up a definite space in the protocol -- we can either set it to 0, or perhaps just leave it out. -- -- Accelerate MD4 Perhaps borrow an assembler MD4 from someone? Make sure we call MD4 with properly-sized blocks whenever possible to avoid copying into the residue region? -- -- TESTING -------------------------------------------------------------- Torture test Something that just keeps running rsync continuously over a data set likely to generate problems. -- -- Cross-test versions 2001/08/22 Part of the regression suite should be making sure that we don't break backwards compatibility: old clients vs new servers and so on. Ideally we would test both up and down from the current release to all old versions. Run current rsync versions against significant past releases. We might need to omit broken old versions, or versions in which particular functionality is broken It might be sufficient to test downloads from well-known public rsync servers running different versions of rsync. This will give some testing and also be the most common case for having different versions and not being able to upgrade. The new --protocol option may help in this. -- -- Test on kernel source Download all versions of kernel; unpack, sync between them. Also sync between uncompressed tarballs. Compare directories after transfer. Use local mode; ssh; daemon; --whole-file and --no-whole-file. Use awk to pull out the 'speedup' number for each transfer. Make sure it is >= x. -- -- Test large files Sparse and non-sparse -- -- Create mutator program for testing Insert bytes, delete bytes, swap blocks, ... -- -- Create configure option to enable dangerous tests -- -- If tests are skipped, say why. -- -- Test daemon feature to disallow particular options. -- -- Create pipe program for testing Create pipe program that makes slow/jerky connections for testing Versions of read() and write() that corrupt the stream, or abruptly fail -- -- Create test makefile target for some tests Separate makefile target to run rough tests -- or perhaps just run them every time? -- -- RELATED PROJECTS ----------------------------------------------------- rsyncsh Write a small emulation of interactive ftp as a Pythonn program that calls rsync. Commands such as "cd", "ls", "ls *.c" etc map fairly directly into rsync commands: it just needs to remember the current host, directory and so on. We can probably even do completion of remote filenames. -- -- http://rsync.samba.org/rsync-and-debian/ -- -- rsyncable gzip patch Exhaustive, tortuous testing Cleanups? -- -- rsyncsplit as alternative to real integration with gzip? -- -- reverse rsync over HTTP Range Goswin Brederlow suggested this on Debian; I think tridge and I talked about it previous in relation to rproxy. -- --