atomicupdate: add an experimental option to use atomictemp when updating
In some cases Mercurial truncating files when updating causes problems. It can
happens when processes are currently reading the file or with big file or on
NFS mounts.
We add an experimental option to use the atomictemp option of vfs.__call__ in
order to avoid the problem.
The localrepository.wwrite seems to assume the files are created without the
`x` flag; with atomictempfile, the new file might inherit the `x` flag from
the destination. We force remove it afterward. This code could be refactored
and the flag processing could be moved inside vfs.
This patch should be tested with
`--extra-config-opt experimental.update.atomic-file=True`
as we disabled the option by default.
Differential Revision: https://phab.mercurial-scm.org/D1882
from __future__ import absolute_import
import array
import errno
import fcntl
import os
import sys
from . import (
encoding,
pycompat,
util,
)
# BSD 'more' escapes ANSI color sequences by default. This can be disabled by
# $MORE variable, but there's no compatible option with Linux 'more'. Given
# OS X is widely used and most modern Unix systems would have 'less', setting
# 'less' as the default seems reasonable.
fallbackpager = 'less'
def _rcfiles(path):
rcs = [os.path.join(path, 'hgrc')]
rcdir = os.path.join(path, 'hgrc.d')
try:
rcs.extend([os.path.join(rcdir, f)
for f, kind in util.listdir(rcdir)
if f.endswith(".rc")])
except OSError:
pass
return rcs
def systemrcpath():
path = []
if pycompat.sysplatform == 'plan9':
root = 'lib/mercurial'
else:
root = 'etc/mercurial'
# old mod_python does not set sys.argv
if len(getattr(sys, 'argv', [])) > 0:
p = os.path.dirname(os.path.dirname(pycompat.sysargv[0]))
if p != '/':
path.extend(_rcfiles(os.path.join(p, root)))
path.extend(_rcfiles('/' + root))
return path
def userrcpath():
if pycompat.sysplatform == 'plan9':
return [encoding.environ['home'] + '/lib/hgrc']
elif pycompat.isdarwin:
return [os.path.expanduser('~/.hgrc')]
else:
confighome = encoding.environ.get('XDG_CONFIG_HOME')
if confighome is None or not os.path.isabs(confighome):
confighome = os.path.expanduser('~/.config')
return [os.path.expanduser('~/.hgrc'),
os.path.join(confighome, 'hg', 'hgrc')]
def termsize(ui):
try:
import termios
TIOCGWINSZ = termios.TIOCGWINSZ # unavailable on IRIX (issue3449)
except (AttributeError, ImportError):
return 80, 24
for dev in (ui.ferr, ui.fout, ui.fin):
try:
try:
fd = dev.fileno()
except AttributeError:
continue
if not os.isatty(fd):
continue
arri = fcntl.ioctl(fd, TIOCGWINSZ, '\0' * 8)
height, width = array.array(r'h', arri)[:2]
if width > 0 and height > 0:
return width, height
except ValueError:
pass
except IOError as e:
if e[0] == errno.EINVAL:
pass
else:
raise
return 80, 24