[pacman-dev] Downgradability...sort of....

[Jatheendra]

Hi all,
Im trying to add some downgradability magic into pacman .Being quite
new to pacman code, i need your help  to identify the possible
pitfalls of my approach before trying something.

What i plan to do is..

In libalpm/remove.c  unlink_file()  [ I guess remove.c is the only
place where we are removing files ]

replace all unlink(), rename() etc with  copyandunlink , copyandrename
etc which will copy the file first into an archive file
package-backup.tgs in cache,then do unlink or rename. Then finally
include  all the necessary .INSTALL ,PKGINFO ,.CHANGELOG etc and clean
up.

So even if i do a -Scc i will have a backup of what was installed on
my system and can roll back to the previous state.

And can sombody please point me to some documentation for libarchive
apart from the manpages...

Jatheendra