# linuxserver.py - inotify status server for linux
#
# Copyright 2006, 2007, 2008 Bryan O'Sullivan <bos@serpentine.com>
# Copyright 2007, 2008 Brendan Cully <brendan@kublai.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from mercurial.i18n import _
from mercurial import osutil, util
import server
import errno, os, select, stat, sys, time
try:
import linux as inotify
from linux import watcher
except ImportError:
raise
def walkrepodirs(dirstate, absroot):
'''Iterate over all subdirectories of this repo.
Exclude the .hg directory, any nested repos, and ignored dirs.'''
def walkit(dirname, top):
fullpath = server.join(absroot, dirname)
try:
for name, kind in osutil.listdir(fullpath):
if kind == stat.S_IFDIR:
if name == '.hg':
if not top:
return
else:
d = server.join(dirname, name)
if dirstate._ignore(d):
continue
for subdir in walkit(d, False):
yield subdir
except OSError, err:
if err.errno not in server.walk_ignored_errors:
raise
yield fullpath
return walkit('', True)
def _explain_watch_limit(ui, dirstate, rootabs):
path = '/proc/sys/fs/inotify/max_user_watches'
try:
limit = int(file(path).read())
except IOError, err:
if err.errno != errno.ENOENT:
raise
raise util.Abort(_('this system does not seem to '
'support inotify'))
ui.warn(_('*** the current per-user limit on the number '
'of inotify watches is %s\n') % limit)
ui.warn(_('*** this limit is too low to watch every '
'directory in this repository\n'))
ui.warn(_('*** counting directories: '))
ndirs = len(list(walkrepodirs(dirstate, rootabs)))
ui.warn(_('found %d\n') % ndirs)
newlimit = min(limit, 1024)
while newlimit < ((limit + ndirs) * 1.1):
newlimit *= 2
ui.warn(_('*** to raise the limit from %d to %d (run as root):\n') %
(limit, newlimit))
ui.warn(_('*** echo %d > %s\n') % (newlimit, path))
raise util.Abort(_('cannot watch %s until inotify watch limit is raised')
% rootabs)
class pollable(object):
"""
Interface to support polling.
The file descriptor returned by fileno() is registered to a polling
object.
Usage:
Every tick, check if an event has happened since the last tick:
* If yes, call handle_events
* If no, call handle_timeout
"""
poll_events = select.POLLIN
instances = {}
poll = select.poll()
def fileno(self):
raise NotImplementedError
def handle_events(self, events):
raise NotImplementedError
def handle_timeout(self):
raise NotImplementedError
def shutdown(self):
raise NotImplementedError
def register(self, timeout):
fd = self.fileno()
pollable.poll.register(fd, pollable.poll_events)
pollable.instances[fd] = self
self.registered = True
self.timeout = timeout
def unregister(self):
pollable.poll.unregister(self)
self.registered = False
@classmethod
def run(cls):
while True:
timeout = None
timeobj = None
for obj in cls.instances.itervalues():
if obj.timeout is not None and (timeout is None
or obj.timeout < timeout):
timeout, timeobj = obj.timeout, obj
try:
events = cls.poll.poll(timeout)
except select.error, err:
if err.args[0] == errno.EINTR:
continue
raise
if events:
by_fd = {}
for fd, event in events:
by_fd.setdefault(fd, []).append(event)
for fd, events in by_fd.iteritems():
cls.instances[fd].handle_pollevents(events)
elif timeobj:
timeobj.handle_timeout()
def eventaction(code):
"""
Decorator to help handle events in repowatcher
"""
def decorator(f):
def wrapper(self, wpath):
if code == 'm' and wpath in self.lastevent and \
self.lastevent[wpath] in 'cm':
return
self.lastevent[wpath] = code
self.timeout = 250
f(self, wpath)
wrapper.func_name = f.func_name
return wrapper
return decorator
class repowatcher(server.repowatcher, pollable):
"""
Watches inotify events
"""
mask = (
inotify.IN_ATTRIB |
inotify.IN_CREATE |
inotify.IN_DELETE |
inotify.IN_DELETE_SELF |
inotify.IN_MODIFY |
inotify.IN_MOVED_FROM |
inotify.IN_MOVED_TO |
inotify.IN_MOVE_SELF |
inotify.IN_ONLYDIR |
inotify.IN_UNMOUNT |
0)
def __init__(self, ui, dirstate, root):
server.repowatcher.__init__(self, ui, dirstate, root)
self.lastevent = {}
self.dirty = False
try:
self.watcher = watcher.watcher()
except OSError, err:
raise util.Abort(_('inotify service not available: %s') %
err.strerror)
self.threshold = watcher.threshold(self.watcher)
self.fileno = self.watcher.fileno
self.register(timeout=None)
self.handle_timeout()
self.scan()
def event_time(self):
last = self.last_event
now = time.time()
self.last_event = now
if last is None:
return 'start'
delta = now - last
if delta < 5:
return '+%.3f' % delta
if delta < 50:
return '+%.2f' % delta
return '+%.1f' % delta
def add_watch(self, path, mask):
if not path:
return
if self.watcher.path(path) is None:
if self.ui.debugflag:
self.ui.note(_('watching %r\n') % path[self.prefixlen:])
try:
self.watcher.add(path, mask)
except OSError, err:
if err.errno in (errno.ENOENT, errno.ENOTDIR):
return
if err.errno != errno.ENOSPC:
raise
_explain_watch_limit(self.ui, self.dirstate, self.wprefix)
def setup(self):
self.ui.note(_('watching directories under %r\n') % self.wprefix)
self.add_watch(self.wprefix + '.hg', inotify.IN_DELETE)
def scan(self, topdir=''):
ds = self.dirstate._map.copy()
self.add_watch(server.join(self.wprefix, topdir), self.mask)
for root, dirs, files in server.walk(self.dirstate, self.wprefix,
topdir):
for d in dirs:
self.add_watch(server.join(root, d), self.mask)
wroot = root[self.prefixlen:]
for fn in files:
wfn = server.join(wroot, fn)
self.updatefile(wfn, self.getstat(wfn))
ds.pop(wfn, None)
wtopdir = topdir
if wtopdir and wtopdir[-1] != '/':
wtopdir += '/'
for wfn, state in ds.iteritems():
if not wfn.startswith(wtopdir):
continue
try:
st = self.stat(wfn)
except OSError:
status = state[0]
self.deletefile(wfn, status)
else:
self.updatefile(wfn, st)
self.check_deleted('!')
self.check_deleted('r')
@eventaction('c')
def created(self, wpath):
if wpath == '.hgignore':
self.update_hgignore()
try:
st = self.stat(wpath)
if stat.S_ISREG(st[0]) or stat.S_ISLNK(st[0]):
self.updatefile(wpath, st)
except OSError:
pass
@eventaction('m')
def modified(self, wpath):
if wpath == '.hgignore':
self.update_hgignore()
try:
st = self.stat(wpath)
if stat.S_ISREG(st[0]):
if self.dirstate[wpath] in 'lmn':
self.updatefile(wpath, st)
except OSError:
pass
@eventaction('d')
def deleted(self, wpath):
if wpath == '.hgignore':
self.update_hgignore()
elif wpath.startswith('.hg/'):
return
self.deletefile(wpath, self.dirstate[wpath])
def process_create(self, wpath, evt):
if self.ui.debugflag:
self.ui.note(_('%s event: created %s\n') %
(self.event_time(), wpath))
if evt.mask & inotify.IN_ISDIR:
self.scan(wpath)
else:
self.created(wpath)
def process_delete(self, wpath, evt):
if self.ui.debugflag:
self.ui.note(_('%s event: deleted %s\n') %
(self.event_time(), wpath))
if evt.mask & inotify.IN_ISDIR:
tree = self.tree.dir(wpath)
todelete = [wfn for wfn, ignore in tree.walk('?')]
for fn in todelete:
self.deletefile(fn, '?')
self.scan(wpath)
else:
self.deleted(wpath)
def process_modify(self, wpath, evt):
if self.ui.debugflag:
self.ui.note(_('%s event: modified %s\n') %
(self.event_time(), wpath))
if not (evt.mask & inotify.IN_ISDIR):
self.modified(wpath)
def process_unmount(self, evt):
self.ui.warn(_('filesystem containing %s was unmounted\n') %
evt.fullpath)
sys.exit(0)
def handle_pollevents(self, events):
if self.ui.debugflag:
self.ui.note(_('%s readable: %d bytes\n') %
(self.event_time(), self.threshold.readable()))
if not self.threshold():
if self.registered:
if self.ui.debugflag:
self.ui.note(_('%s below threshold - unhooking\n') %
(self.event_time()))
self.unregister()
self.timeout = 250
else:
self.read_events()
def read_events(self, bufsize=None):
events = self.watcher.read(bufsize)
if self.ui.debugflag:
self.ui.note(_('%s reading %d events\n') %
(self.event_time(), len(events)))
for evt in events:
if evt.fullpath == self.wprefix[:-1]:
# events on the root of the repository
# itself, e.g. permission changes or repository move
continue
assert evt.fullpath.startswith(self.wprefix)
wpath = evt.fullpath[self.prefixlen:]
# paths have been normalized, wpath never ends with a '/'
if wpath.startswith('.hg/') and evt.mask & inotify.IN_ISDIR:
# ignore subdirectories of .hg/ (merge, patches...)
continue
if wpath == ".hg/wlock":
if evt.mask & inotify.IN_DELETE:
self.dirstate.invalidate()
self.dirty = False
self.scan()
elif evt.mask & inotify.IN_CREATE:
self.dirty = True
else:
if self.dirty:
continue
if evt.mask & inotify.IN_UNMOUNT:
self.process_unmount(wpath, evt)
elif evt.mask & (inotify.IN_MODIFY | inotify.IN_ATTRIB):
self.process_modify(wpath, evt)
elif evt.mask & (inotify.IN_DELETE | inotify.IN_DELETE_SELF |
inotify.IN_MOVED_FROM):
self.process_delete(wpath, evt)
elif evt.mask & (inotify.IN_CREATE | inotify.IN_MOVED_TO):
self.process_create(wpath, evt)
self.lastevent.clear()
def handle_timeout(self):
if not self.registered:
if self.ui.debugflag:
self.ui.note(_('%s hooking back up with %d bytes readable\n') %
(self.event_time(), self.threshold.readable()))
self.read_events(0)
self.register(timeout=None)
self.timeout = None
def shutdown(self):
self.watcher.close()
def debug(self):
"""
Returns a sorted list of relatives paths currently watched,
for debugging purposes.
"""
return sorted(tuple[0][self.prefixlen:] for tuple in self.watcher)
class socketlistener(server.socketlistener, pollable):
"""
Listens for client queries on unix socket inotify.sock
"""
def __init__(self, ui, root, repowatcher, timeout):
server.socketlistener.__init__(self, ui, root, repowatcher, timeout)
self.register(timeout=timeout)
def handle_timeout(self):
raise server.TimeoutException
def handle_pollevents(self, events):
for e in events:
self.accept_connection()
def shutdown(self):
self.sock.close()
try:
os.unlink(self.sockpath)
if self.realsockpath:
os.unlink(self.realsockpath)
os.rmdir(os.path.dirname(self.realsockpath))
except OSError, err:
if err.errno != errno.ENOENT:
raise
def answer_stat_query(self, cs):
if self.repowatcher.timeout:
# We got a query while a rescan is pending. Make sure we
# rescan before responding, or we could give back a wrong
# answer.
self.repowatcher.handle_timeout()
return server.socketlistener.answer_stat_query(self, cs)
class master(object):
def __init__(self, ui, dirstate, root, timeout=None):
self.ui = ui
self.repowatcher = repowatcher(ui, dirstate, root)
self.socketlistener = socketlistener(ui, root, self.repowatcher,
timeout)
def shutdown(self):
for obj in pollable.instances.itervalues():
obj.shutdown()
def run(self):
self.repowatcher.setup()
self.ui.note(_('finished setup\n'))
if os.getenv('TIME_STARTUP'):
sys.exit(0)
pollable.run()