bdiff: don't check border condition in loop
This is pretty much a copy of d500ddae7494, just to a different loop.
The condition `p == plast` (`plast == a + len - 1`) was only true on
the final iteration of the loop. So it was wasteful to check for it
on every iteration. We decrease the iteration count by 1 and add an
explicit check for `p == plast` after the loop.
Again, we see modest wins.
From the mozilla-unified repository:
$ perfbdiff -m 3041e4d59df2
! wall 0.035502 comb 0.040000 user 0.040000 sys 0.000000 (best of 100)
! wall 0.030480 comb 0.030000 user 0.030000 sys 0.000000 (best of 100)
$ perfbdiff 0e9928989e9c --alldata --count 100
! wall 4.097394 comb 4.100000 user 4.100000 sys 0.000000 (best of 3)
! wall 3.597798 comb 3.600000 user 3.600000 sys 0.000000 (best of 3)
The 2nd example throws a total of ~3.3GB of data at bdiff. This
change increases the throughput from ~811 MB/s to ~924 MB/s.
#!/usr/bin/env python
#
# Copyright 2005-2007 by Intevation GmbH <intevation@intevation.de>
#
# Author(s):
# Thomas Arendsen Hein <thomas@intevation.de>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""
hg-ssh - a wrapper for ssh access to a limited set of mercurial repos
To be used in ~/.ssh/authorized_keys with the "command" option, see sshd(8):
command="hg-ssh path/to/repo1 /path/to/repo2 ~/repo3 ~user/repo4" ssh-dss ...
(probably together with these other useful options:
no-port-forwarding,no-X11-forwarding,no-agent-forwarding)
This allows pull/push over ssh from/to the repositories given as arguments.
If all your repositories are subdirectories of a common directory, you can
allow shorter paths with:
command="cd path/to/my/repositories && hg-ssh repo1 subdir/repo2"
You can use pattern matching of your normal shell, e.g.:
command="cd repos && hg-ssh user/thomas/* projects/{mercurial,foo}"
You can also add a --read-only flag to allow read-only access to a key, e.g.:
command="hg-ssh --read-only repos/*"
"""
# enable importing on demand to reduce startup time
from mercurial import demandimport; demandimport.enable()
from mercurial import dispatch
import sys, os, shlex
def main():
cwd = os.getcwd()
readonly = False
args = sys.argv[1:]
while len(args):
if args[0] == '--read-only':
readonly = True
args.pop(0)
else:
break
allowed_paths = [os.path.normpath(os.path.join(cwd,
os.path.expanduser(path)))
for path in args]
orig_cmd = os.getenv('SSH_ORIGINAL_COMMAND', '?')
try:
cmdargv = shlex.split(orig_cmd)
except ValueError as e:
sys.stderr.write('Illegal command "%s": %s\n' % (orig_cmd, e))
sys.exit(255)
if cmdargv[:2] == ['hg', '-R'] and cmdargv[3:] == ['serve', '--stdio']:
path = cmdargv[2]
repo = os.path.normpath(os.path.join(cwd, os.path.expanduser(path)))
if repo in allowed_paths:
cmd = ['-R', repo, 'serve', '--stdio']
if readonly:
cmd += [
'--config',
'hooks.pretxnopen.hg-ssh=python:__main__.rejectpush',
'--config',
'hooks.prepushkey.hg-ssh=python:__main__.rejectpush'
]
dispatch.dispatch(dispatch.request(cmd))
else:
sys.stderr.write('Illegal repository "%s"\n' % repo)
sys.exit(255)
else:
sys.stderr.write('Illegal command "%s"\n' % orig_cmd)
sys.exit(255)
def rejectpush(ui, **kwargs):
ui.warn(("Permission denied\n"))
# mercurial hooks use unix process conventions for hook return values
# so a truthy return means failure
return True
if __name__ == '__main__':
main()