+ - 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.
+
+ -- --
+
+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.
+
+ 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.
+
+ -- --