bspatch thus does not verify file hashes, and that consequently it
is recommended that users store hashes separately and verify files
before and after running bspatch.
Requested by: BugMagnet
MFC after: 1 week
constructing and applying binary patches; in particular, they perform
well (in the sense of constructing small patches) for executable code.
Both portsnap (coming to the base system Real Soon Now) and FreeBSD
Update (coming to the base system a bit later) use bspatch.
This is the same code as the bsdiff-4.2 which has been in the ports
tree (misc/bsdiff) for the past year, with the following exceptions:
1. The license is now the traditional 2-clause BSD;
2. Instead of forking and execing bzip2, the code now uses libbz2; and
3. Some minor changes have been made to fit this code into the base
system (adding $FreeBSD$ tags, putting bsdiff and bspatch into separate
directories, etc.)
This code is rather ugly and has lots of style bugs (mostly because I
wrote it before I had ever heard of style(9)). Some day I'll come
back and clean it up.
Discussed on: freebsd-arch
MFC before: 5.5-RELEASE
Tested by: Several million users (earlier version).
