revlog: add clone method
Upcoming patches will introduce functionality for in-place
repository/store "upgrades." Copying the contents of a revlog
feels sufficiently low-level to warrant being in the revlog
class. So this commit implements that functionality.
Because full delta recomputation can be *very* expensive (we're
talking several hours on the Firefox repository), we support
multiple modes of execution with regards to delta (re)use. This
will allow repository upgrades to choose the "level" of
processing/optimization they wish to perform when converting
revlogs.
It's not obvious from this commit, but "addrevisioncb" will be
used for progress reporting.
#!/bin/rc
# 9mail - Mercurial email wrapper for upas/marshal
fn usage {
echo >[1=2] usage: mercurial/9mail -f from to [cc]
exit usage
}
from=()
cc=()
to=()
switch($1){
case -f
from=$2
case *
usage
}
to=($3)
if(~ $#* 4)
cc=(-C $4)
upasname=$from
upas/marshal $cc $to