-*- indented-text -*-
-URGENT ---------------------------------------------------------------
+FEATURES ------------------------------------------------------------
+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
+proxy authentication 2002/01/23
+SOCKS 2002/01/23
+FAT support
+--diff david.e.sewell 2002/03/15
+Add daemon --no-fork option
+Create more granular verbosity 2003/05/15
+DOCUMENTATION --------------------------------------------------------
+Keep list of open issues and todos on the web site
+Perhaps redo manual as SGML
-IMPORTANT ------------------------------------------------------------
+LOGGING --------------------------------------------------------------
+Memory accounting
+Improve error messages
+Better statistics Rasmus 2002/03/08
+Perhaps flush stdout like syslog
+Log child death on signal
+verbose output David Stein 2001/12/20
+internationalization
-Cross-test versions
+DEVELOPMENT --------------------------------------------------------
+Handling duplicate names
+Use generic zlib 2002/02/25
+TDB 2002/03/12
+Splint 2002/03/12
+
+PERFORMANCE ----------------------------------------------------------
+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
+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
- 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 the cross product of versions.
- 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.
-use chroot
+FEATURES ------------------------------------------------------------
+
+
+Use chroot only if supported
If the platform doesn't support it, then don't even try.
http://lists.samba.org/pipermail/rsync/2001-August/thread.html
http://lists.samba.org/pipermail/rsync/2001-September/thread.html
---files-from
+ -- --
- Avoids traversal. Better option than a pile of --include statements
- for people who want to generate the file list using a find(1)
- command or a script.
-File list structure in memory
+Allow supplementary groups in rsyncd.conf 2002/04/09
- Rather than one big array, perhaps have a tree in memory mirroring
- the directory tree.
+ 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.
- 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.
-Performance
+Handling IPv6 on old machines
- Traverse just one directory at a time. Tridge says it's possible.
+ 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.
- 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.
+ 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.
-Handling duplicate names
+ 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 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.
+ We could drop the rather large lib/getaddrinfo files.
- 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.
+Other IPv6 stuff
+
+ Implement suggestions from http://www.kame.net/newsletter/19980604/
+ and ftp://ftp.iij.ad.jp/pub/RFC/rfc2553.txt
- We could have a hash table.
+ 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.
- 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.
+ 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.
- 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.
+Add ACL support 2001/12/02
- I think even if we're using a different symlink mode we don't need
- to worry.
+ 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.
+ NOTE: there is a patch that implements this in the "patches" subdir.
- Unless we're really clever this will introduce a protocol
- incompatibility, so we need to be able to accept the old format as
- well.
+ -- --
-Memory accounting
+proxy authentication 2002/01/23
- At exit, show how much memory was used for the file list, etc.
+ Allow RSYNC_PROXY to be http://user:pass@proxy.foo:3128/, and do
+ HTTP Basic Proxy-Authentication.
- 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.
+ Multiple schemes are possible, up to and including the insanity that
+ is NTLM, but Basic probably covers most cases.
- We can try using the GNU/SVID/XPG mallinfo() function to get some
- heap statistics.
+ -- --
-Hard-link handling
+SOCKS 2002/01/23
- At the moment hardlink handling is very expensive, so it's off by
- default. It does not need to be so.
+ 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.
- Since most of the solutions are rather intertwined with the file
- list it is probably better to fix that first, although fixing
- hardlinks is possibly simpler.
+ -- --
- We can rule out hardlinked directories since they will probably
- screw us up in all kinds of ways. They simply should not be used.
- At the moment rsync only cares about hardlinks to regular files. I
- guess you could also use them for sockets, devices and other beasts,
- but I have not seen them.
+FAT support
- When trying to reproduce hard links, we only need to worry about
- files that have more than one name (nlinks>1 && !S_ISDIR).
+ 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.
- The basic point of this is to discover alternate names that refer to
- the same file. All operations, including creating the file and
- writing modifications to it need only to be done for the first name.
- For all later names, we just create the link and then leave it
- alone.
+ 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.
- If hard links are to be preserved:
+ -- --
- Before the generator/receiver fork, the list of files is received
- from the sender (recv_file_list), and a table for detecting hard
- links is built.
- The generator looks for hard links within the file list and does
- not send checksums for them, though it does send other metadata.
+--diff david.e.sewell 2002/03/15
- The sender sends the device number and inode with file entries, so
- that files are uniquely identified.
+ Allow people to specify the diff command. (Might want to use wdiff,
+ gnudiff, etc.)
- The receiver goes through and creates hard links (do_hard_links)
- after all data has been written, but before directory permissions
- are set.
+ Just diff the temporary file with the destination file, and delete
+ the tmp file rather than moving it into place.
- At the moment device and inum are sent as 4-byte integers, which
- will probably cause problems on large filesystems. On Linux the
- kernel uses 64-bit ino_t's internally, and people will soon have
- filesystems big enough to use them. We ought to follow NFS4 in
- using 64-bit device and inode identification, perhaps with a
- protocol version bump.
+ Interaction with --partial.
- Once we've seen all the names for a particular file, we no longer
- need to think about it and we can deallocate the memory.
+ Security interactions with daemon mode?
- We can also have the case where there are links to a file that are
- not in the tree being transferred. There's nothing we can do about
- that. Because we rename the destination into place after writing,
- any hardlinks to the old file are always going to be orphaned. In
- fact that is almost necessary because otherwise we'd get really
- confused if we were generating checksums for one name of a file and
- modifying another.
+ -- --
- At the moment the code seems to make a whole second copy of the file
- list, which seems unnecessary.
- We should have a test case that exercises hard links. Since it
- might be hard to compare ./tls output where the inodes change we
- might need a little program to check whether several names refer to
- the same file.
+Add daemon --no-fork option
-IPv6
+ Very useful for debugging. Also good when running under a
+ daemon-monitoring process that tries to restart the service when the
+ parent exits.
- 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.
+Create more granular verbosity 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 --------------------------------------------------------
+
+
+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 --------------------------------------------------------------
- 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.
+Memory accounting
+
+ At exit, show how much memory was used for the file list, etc.
-Errors
+ 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
"The dungeon collapses! You are killed." Rather than "unexpected
eof" give a message that is more detailed if possible and also more
- helpful.
+ helpful.
-File attributes
+ 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.
- Device major/minor numbers should be at least 32 bits each. See
- http://lists.samba.org/pipermail/rsync/2001-November/005357.html
+ 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.
- 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.
+ -- --
+
+
+Better statistics Rasmus 2002/03/08
-Empty directories
+ <Rasmus>
+ 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. ?
- With the current common --include '*/' --exclude '*' pattern, people
- can end up with many empty directories. We might avoid this by
- lazily creating such directories.
+ <mbp>
+ 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
-zlib
+ -- --
- Perhaps don't use our own zlib. Will we actually be incompatible,
- or just be slightly less efficient?
-logging
+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
- At the connections that just get a list of modules are not logged,
- but they should be.
+ -- --
-rsyncd over ssh
- There are already some patches to do this.
+Log child death on signal
-proxy authentication
+ If a child of the rsync daemon dies with a signal, we should notice
+ that when we reap it and log a message.
- 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
+verbose output David Stein 2001/12/20
+
+ At end of transfer, show how many files were or were not transferred
+ correctly.
- 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.
+ -- --
-PLATFORMS ------------------------------------------------------------
-Win32
+internationalization
- Don't detach, because this messes up --srvany.
+ Change to using gettext(). Probably need to ship this for platforms
+ that don't have it.
- http://sources.redhat.com/ml/cygwin/2001-08/msg00234.html
+ Solicit translations.
- According to "Effective TCP/IP Programming" (??) close() on a socket
- has incorrect behaviour on Windows -- it sends a RST packet to the
- other side, which gives a "connection reset by peer" error. On that
- platform we should probably do shutdown() instead. However, on Unix
- we are correct to call close(), because shutdown() discards
- untransmitted data.
+ 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.
-DOCUMENTATION --------------------------------------------------------
+ -- --
-Update README
+DEVELOPMENT --------------------------------------------------------
-BUILD FARM -----------------------------------------------------------
+Handling duplicate names
-Add machines
+ Some folks would like rsync to be deterministic in how it handles
+ duplicate names that come from mering multiple source directories
+ into a single destination directory; e.g. the last name wins. We
+ could do this by switching our sort algorithm to one that will
+ guarantee that the names won't be reordered. Alternately, we could
+ assign an ever-increasing number to each item as we insert it into
+ the list and then make sure that we leave the largest number when
+ cleaning the file list (see clean_flist()). Another solution would
+ be to add a hash table, and thus never put any duplicate names into
+ the file list (and bump the protocol to handle this).
- AMDAHL UTS (Dave Dykstra)
+ -- --
- Cygwin (on different versions of Win32?)
- HP-UX variants (via HP?)
+Use generic zlib 2002/02/25
- SCO
+ Perhaps don't use our own zlib.
-NICE -----------------------------------------------------------------
+ Advantages:
+
+ - will automatically be up to date with bugfixes in zlib
---no-detach and --no-fork options
+ - can leave it out for small rsync on e.g. recovery disks
- Very useful for debugging. Also good when running under a
- daemon-monitoring process that tries to restart the service when the
- parent exits.
+ - can use a shared library
-hang/timeout friendliness
+ - avoids people breaking rsync by trying to do this themselves and
+ messing up
-verbose output
-
- Indicate whether files are new, updated, or deleted
+ Should we ship zlib for systems that don't have it, or require
+ people to install it separately?
-internationalization
+ 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.
- Change to using gettext(). Probably need to ship this for platforms
- that don't have it.
+ -- --
- Solicit translations.
- Does anyone care?
+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.
+
+ -- --
+
+PERFORMANCE ----------------------------------------------------------
+
+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.
+
+ We should not allow it to be disabled separately from -W, though
+ as it is the only thing that lets us know when the rsync algorithm
+ got out of sync and messed the file up (i.e. if the basis file
+ changed between checksum generation and reception).
+
+ -- --
+
+
+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.
-rsyncsh
+ 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
+
+ -- --
+
+
+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
current host, directory and so on. We can probably even do
completion of remote filenames.
-%K%
+ -- --
+
+
+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.
+
+ Addendum: It looks like someone is working on a version of this:
+
+ http://zsync.moria.org.uk/
+
+ -- --
+