inotify: improve error messages

* prefix messages by inotify-(client|server)
* make sure that all warning and abort messages use the same format.
* in the case where inotify.sock is an old broken symlink, say so and abort
  instead of trying to overwrite the already existing link

hgext/inotify/client.py

@@ -1,170 +1,171
 # client.py - inotify status client
 #
 # Copyright 2006, 2007, 2008 Bryan O'Sullivan <[e-mail]>
 # Copyright 2007, 2008 Brendan Cully <[e-mail]>
 # Copyright 2009 Nicolas Dumazet <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2, incorporated herein by reference.
 
 from mercurial.i18n import _
 import common, server
 import errno, os, socket, struct
 
 class QueryFailed(Exception): pass
 
 def start_server(function):
     """
     Decorator.
     Tries to call function, if it fails, try to (re)start inotify server.
     Raise QueryFailed if something went wrong
     """
     def decorated_function(self, *args):
         result = None
         try:
             return function(self, *args)
         except (OSError, socket.error), err:
             autostart = self.ui.configbool('inotify', 'autostart', True)
 
             if err[0] == errno.ECONNREFUSED:
-                self.ui.warn(_('(found dead inotify server socket; '
-                               'removing it)\n'))
+                self.ui.warn(_('inotify-client: found dead inotify server '
+                               'socket; removing it\n'))
                 os.unlink(os.path.join(self.root, '.hg', 'inotify.sock'))
             if err[0] in (errno.ECONNREFUSED, errno.ENOENT) and autostart:
                 self.ui.debug('(starting inotify server)\n')
                 try:
                     try:
                         server.start(self.ui, self.dirstate, self.root,
                                      dict(daemon=True, daemon_pipefds=''))
                     except server.AlreadyStartedException, inst:
                         # another process may have started its own
                         # inotify server while this one was starting.
                         self.ui.debug(str(inst))
                 except Exception, inst:
-                    self.ui.warn(_('could not start inotify server: '
-                                   '%s\n') % inst)
+                    self.ui.warn(_('inotify-client: could not start inotify '
+                                   'server: %s\n') % inst)
                 else:
                     try:
                         return function(self, *args)
                     except socket.error, err:
-                        self.ui.warn(_('could not talk to new inotify '
-                                       'server: %s\n') % err[-1])
+                        self.ui.warn(_('inotify-client: could not talk to new '
+                                       'inotify server: %s\n') % err[-1])
             elif err[0] in (errno.ECONNREFUSED, errno.ENOENT):
                 # silently ignore normal errors if autostart is False
                 self.ui.debug('(inotify server not running)\n')
             else:
-                self.ui.warn(_('failed to contact inotify server: %s\n')
-                         % err[-1])
+                self.ui.warn(_('inotify-client: failed to contact inotify '
+                               'server: %s\n') % err[-1])
 
         self.ui.traceback()
         raise QueryFailed('inotify query failed')
 
     return decorated_function
 
 
 class client(object):
     def __init__(self, ui, repo):
         self.ui = ui
         self.dirstate = repo.dirstate
         self.root = repo.root
         self.sock = socket.socket(socket.AF_UNIX)
 
     def _connect(self):
         sockpath = os.path.join(self.root, '.hg', 'inotify.sock')
         try:
             self.sock.connect(sockpath)
         except socket.error, err:
             if err[0] == "AF_UNIX path too long":
                 sockpath = os.readlink(sockpath)
                 self.sock.connect(sockpath)
             else:
                 raise
 
     def _send(self, type, data):
         """Sends protocol version number, and the data"""
         self.sock.sendall(chr(common.version) + type + data)
 
         self.sock.shutdown(socket.SHUT_WR)
 
     def _receive(self, type):
         """
         Read data, check version number, extract headers,
         and returns a tuple (data descriptor, header)
         Raises QueryFailed on error
         """
         cs = common.recvcs(self.sock)
         try:
             version = ord(cs.read(1))
         except TypeError:
             # empty answer, assume the server crashed
-            self.ui.warn(_('received empty answer from inotify server'))
+            self.ui.warn(_('inotify-client: received empty answer from inotify '
+                           'server'))
             raise QueryFailed('server crashed')
 
         if version != common.version:
             self.ui.warn(_('(inotify: received response from incompatible '
                       'server version %d)\n') % version)
             raise QueryFailed('incompatible server version')
 
         readtype = cs.read(4)
         if readtype != type:
             self.ui.warn(_('(inotify: received \'%s\' response when expecting'
                        ' \'%s\')\n') % (readtype, type))
             raise QueryFailed('wrong response type')
 
         hdrfmt = common.resphdrfmts[type]
         hdrsize = common.resphdrsizes[type]
         try:
             resphdr = struct.unpack(hdrfmt, cs.read(hdrsize))
         except struct.error:
             raise QueryFailed('unable to retrieve query response headers')
 
         return cs, resphdr
 
     def query(self, type, req):
         self._connect()
 
         self._send(type, req)
 
         return self._receive(type)
 
     @start_server
     def statusquery(self, names, match, ignored, clean, unknown=True):
 
         def genquery():
             for n in names:
                 yield n
             states = 'almrx!'
             if ignored:
                 raise ValueError('this is insanity')
             if clean: states += 'c'
             if unknown: states += '?'
             yield states
 
         req = '\0'.join(genquery())
 
         cs, resphdr = self.query('STAT', req)
 
         def readnames(nbytes):
             if nbytes:
                 names = cs.read(nbytes)
                 if names:
                     return filter(match, names.split('\0'))
             return []
         results = map(readnames, resphdr[:-1])
 
         if names:
             nbytes = resphdr[-1]
             vdirs = cs.read(nbytes)
             if vdirs:
                 for vdir in vdirs.split('\0'):
                     match.dir(vdir)
 
         return results
 
     @start_server
     def debugquery(self):
         cs, resphdr = self.query('DBUG', '')
 
         nbytes = resphdr[0]
         names = cs.read(nbytes)
         return names.split('\0')

hgext/inotify/server.py

@@ -1,864 +1,869
 # server.py - inotify status server
 #
 # Copyright 2006, 2007, 2008 Bryan O'Sullivan <[e-mail]>
 # Copyright 2007, 2008 Brendan Cully <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2, incorporated herein by reference.
 
 from mercurial.i18n import _
 from mercurial import cmdutil, osutil, util
 import common
 import errno, os, select, socket, stat, struct, sys, tempfile, time
 
 try:
     import linux as inotify
     from linux import watcher
 except ImportError:
     raise
 
 class AlreadyStartedException(Exception): pass
 
 def join(a, b):
     if a:
         if a[-1] == '/':
             return a + b
         return a + '/' + b
     return b
 
 def split(path):
     c = path.rfind('/')
     if c == -1:
         return '', path
     return path[:c], path[c+1:]
 
 walk_ignored_errors = (errno.ENOENT, errno.ENAMETOOLONG)
 
 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 = 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 = join(dirname, name)
                         if dirstate._ignore(d):
                             continue
                         for subdir in walkit(d, False):
                             yield subdir
         except OSError, err:
             if err.errno not in walk_ignored_errors:
                 raise
         yield fullpath
 
     return walkit('', True)
 
 def walk(dirstate, absroot, root):
     '''Like os.walk, but only yields regular files.'''
 
     # This function is critical to performance during startup.
 
     def walkit(root, reporoot):
         files, dirs = [], []
 
         try:
             fullpath = join(absroot, root)
             for name, kind in osutil.listdir(fullpath):
                 if kind == stat.S_IFDIR:
                     if name == '.hg':
                         if not reporoot:
                             return
                     else:
                         dirs.append(name)
                         path = join(root, name)
                         if dirstate._ignore(path):
                             continue
                         for result in walkit(path, False):
                             yield result
                 elif kind in (stat.S_IFREG, stat.S_IFLNK):
                     files.append(name)
             yield fullpath, dirs, files
 
         except OSError, err:
             if err.errno == errno.ENOTDIR:
                 # fullpath was a directory, but has since been replaced
                 # by a file.
                 yield fullpath, dirs, files
             elif err.errno not in walk_ignored_errors:
                 raise
 
     return walkit(root, root == '')
 
 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[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 directory(object):
     """
     Representing a directory
 
     * path is the relative path from repo root to this directory
     * files is a dict listing the files in this directory
         - keys are file names
         - values are file status
     * dirs is a dict listing the subdirectories
         - key are subdirectories names
         - values are directory objects
     """
     def __init__(self, relpath=''):
         self.path = relpath
         self.files = {}
         self.dirs = {}
 
     def dir(self, relpath):
         """
         Returns the directory contained at the relative path relpath.
         Creates the intermediate directories if necessary.
         """
         if not relpath:
             return self
         l = relpath.split('/')
         ret = self
         while l:
             next = l.pop(0)
             try:
                 ret = ret.dirs[next]
             except KeyError:
                 d = directory(join(ret.path, next))
                 ret.dirs[next] = d
                 ret = d
         return ret
 
     def walk(self, states, visited=None):
         """
         yield (filename, status) pairs for items in the trees
         that have status in states.
         filenames are relative to the repo root
         """
         for file, st in self.files.iteritems():
             if st in states:
                 yield join(self.path, file), st
         for dir in self.dirs.itervalues():
             if visited is not None:
                 visited.add(dir.path)
             for e in dir.walk(states):
                 yield e
 
     def lookup(self, states, path, visited):
         """
         yield root-relative filenames that match path, and whose
         status are in states:
         * if path is a file, yield path
         * if path is a directory, yield directory files
         * if path is not tracked, yield nothing
         """
         if path[-1] == '/':
             path = path[:-1]
 
         paths = path.split('/')
 
         # we need to check separately for last node
         last = paths.pop()
 
         tree = self
         try:
             for dir in paths:
                 tree = tree.dirs[dir]
         except KeyError:
             # path is not tracked
             visited.add(tree.path)
             return
 
         try:
             # if path is a directory, walk it
             target = tree.dirs[last]
             visited.add(target.path)
             for file, st in target.walk(states, visited):
                 yield file
         except KeyError:
             try:
                 if tree.files[last] in states:
                     # path is a file
                     visited.add(tree.path)
                     yield path
             except KeyError:
                 # path is not tracked
                 pass
 
 class repowatcher(pollable):
     """
     Watches inotify events
     """
     statuskeys = 'almr!?'
     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):
         self.ui = ui
         self.dirstate = dirstate
 
         self.wprefix = join(root, '')
         self.prefixlen = len(self.wprefix)
         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.tree = directory()
         self.statcache = {}
         self.statustrees = dict([(s, directory()) for s in self.statuskeys])
 
         self.last_event = None
 
         self.lastevent = {}
 
         self.register(timeout=None)
 
         self.ds_info = self.dirstate_info()
         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 dirstate_info(self):
         try:
             st = os.lstat(self.wprefix + '.hg/dirstate')
             return st.st_mtime, st.st_ino
         except OSError, err:
             if err.errno != errno.ENOENT:
                 raise
             return 0, 0
 
     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)
         self.check_dirstate()
 
     def filestatus(self, fn, st):
         try:
             type_, mode, size, time = self.dirstate._map[fn][:4]
         except KeyError:
             type_ = '?'
         if type_ == 'n':
             st_mode, st_size, st_mtime = st
             if size == -1:
                 return 'l'
             if size and (size != st_size or (mode ^ st_mode) & 0100):
                 return 'm'
             if time != int(st_mtime):
                 return 'l'
             return 'n'
         if type_ == '?' and self.dirstate._ignore(fn):
             return 'i'
         return type_
 
     def updatefile(self, wfn, osstat):
         '''
         update the file entry of an existing file.
 
         osstat: (mode, size, time) tuple, as returned by os.lstat(wfn)
         '''
 
         self._updatestatus(wfn, self.filestatus(wfn, osstat))
 
     def deletefile(self, wfn, oldstatus):
         '''
         update the entry of a file which has been deleted.
 
         oldstatus: char in statuskeys, status of the file before deletion
         '''
         if oldstatus == 'r':
             newstatus = 'r'
         elif oldstatus in 'almn':
             newstatus = '!'
         else:
             newstatus = None
 
         self.statcache.pop(wfn, None)
         self._updatestatus(wfn, newstatus)
 
     def _updatestatus(self, wfn, newstatus):
         '''
         Update the stored status of a file.
 
         newstatus: - char in (statuskeys + 'ni'), new status to apply.
                    - or None, to stop tracking wfn
         '''
         root, fn = split(wfn)
         d = self.tree.dir(root)
 
         oldstatus = d.files.get(fn)
         # oldstatus can be either:
         # - None : fn is new
         # - a char in statuskeys: fn is a (tracked) file
 
         if self.ui.debugflag and oldstatus != newstatus:
             self.ui.note(_('status: %r %s -> %s\n') %
                              (wfn, oldstatus, newstatus))
 
         if oldstatus and oldstatus in self.statuskeys \
             and oldstatus != newstatus:
             del self.statustrees[oldstatus].dir(root).files[fn]
 
         if newstatus in (None, 'i'):
             d.files.pop(fn, None)
         elif oldstatus != newstatus:
             d.files[fn] = newstatus
             if newstatus != 'n':
                 self.statustrees[newstatus].dir(root).files[fn] = newstatus
 
 
     def check_deleted(self, key):
         # Files that had been deleted but were present in the dirstate
         # may have vanished from the dirstate; we must clean them up.
         nuke = []
         for wfn, ignore in self.statustrees[key].walk(key):
             if wfn not in self.dirstate:
                 nuke.append(wfn)
         for wfn in nuke:
             root, fn = split(wfn)
             del self.statustrees[key].dir(root).files[fn]
             del self.tree.dir(root).files[fn]
 
     def scan(self, topdir=''):
         ds = self.dirstate._map.copy()
         self.add_watch(join(self.wprefix, topdir), self.mask)
         for root, dirs, files in walk(self.dirstate, self.wprefix, topdir):
             for d in dirs:
                 self.add_watch(join(root, d), self.mask)
             wroot = root[self.prefixlen:]
             for fn in files:
                 wfn = 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')
 
     def check_dirstate(self):
         ds_info = self.dirstate_info()
         if ds_info == self.ds_info:
             return
         self.ds_info = ds_info
         if not self.ui.debugflag:
             self.last_event = None
         self.ui.note(_('%s dirstate reload\n') % self.event_time())
         self.dirstate.invalidate()
         self.handle_timeout()
         self.scan()
         self.ui.note(_('%s end dirstate reload\n') % self.event_time())
 
     def update_hgignore(self):
         # An update of the ignore file can potentially change the
         # states of all unknown and ignored files.
 
         # XXX If the user has other ignore files outside the repo, or
         # changes their list of ignore files at run time, we'll
         # potentially never see changes to them.  We could get the
         # client to report to us what ignore data they're using.
         # But it's easier to do nothing than to open that can of
         # worms.
 
         if '_ignore' in self.dirstate.__dict__:
             delattr(self.dirstate, '_ignore')
             self.ui.note(_('rescanning due to .hgignore change\n'))
             self.handle_timeout()
             self.scan()
 
     def getstat(self, wpath):
         try:
             return self.statcache[wpath]
         except KeyError:
             try:
                 return self.stat(wpath)
             except OSError, err:
                 if err.errno != errno.ENOENT:
                     raise
 
     def stat(self, wpath):
         try:
             st = os.lstat(join(self.wprefix, wpath))
             ret = st.st_mode, st.st_size, st.st_mtime
             self.statcache[wpath] = ret
             return ret
         except OSError:
             self.statcache.pop(wpath, None)
             raise
 
     @eventaction('c')
     def created(self, wpath):
         if wpath == '.hgignore':
             self.update_hgignore()
         try:
             st = self.stat(wpath)
             if stat.S_ISREG(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/'):
             if wpath == '.hg/wlock':
                 self.check_dirstate()
             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:
             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 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 server(pollable):
     """
     Listens for client queries on unix socket inotify.sock
     """
     def __init__(self, ui, root, repowatcher, timeout):
         self.ui = ui
         self.repowatcher = repowatcher
         self.sock = socket.socket(socket.AF_UNIX)
         self.sockpath = join(root, '.hg/inotify.sock')
         self.realsockpath = None
         try:
             self.sock.bind(self.sockpath)
         except socket.error, err:
             if err[0] == errno.EADDRINUSE:
-                raise AlreadyStartedException(_('could not start server: %s')
-                                              % err[1])
+                raise AlreadyStartedException( _('cannot start: socket is '
+                                                 'already bound'))
             if err[0] == "AF_UNIX path too long":
+                if os.path.islink(self.sockpath) and \
+                        not os.path.exists(self.sockpath):
+                    raise util.Abort('inotify-server: cannot start: '
+                                    '.hg/inotify.sock is a broken symlink')
                 tempdir = tempfile.mkdtemp(prefix="hg-inotify-")
                 self.realsockpath = os.path.join(tempdir, "inotify.sock")
                 try:
                     self.sock.bind(self.realsockpath)
                     os.symlink(self.realsockpath, self.sockpath)
                 except (OSError, socket.error), inst:
                     try:
                         os.unlink(self.realsockpath)
                     except:
                         pass
                     os.rmdir(tempdir)
                     if inst.errno == errno.EEXIST:
-                        raise AlreadyStartedException(_('could not start server: %s')
-                                                      % inst.strerror)
+                        raise AlreadyStartedException(_('cannot start: tried '
+                            'linking .hg/inotify.sock to a temporary socket but'
+                            ' .hg/inotify.sock already exists'))
                     raise
             else:
                 raise
         self.sock.listen(5)
         self.fileno = self.sock.fileno
         self.register(timeout=timeout)
 
     def handle_timeout(self):
         pass
 
     def answer_stat_query(self, cs):
         names = cs.read().split('\0')
 
         states = names.pop()
 
         self.ui.note(_('answering query for %r\n') % states)
 
         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()
 
         visited = set()
         if not names:
             def genresult(states, tree):
                 for fn, state in tree.walk(states):
                     yield fn
         else:
             def genresult(states, tree):
                 for fn in names:
                     for f in tree.lookup(states, fn, visited):
                         yield f
 
         return ['\0'.join(r) for r in [
             genresult('l', self.repowatcher.statustrees['l']),
             genresult('m', self.repowatcher.statustrees['m']),
             genresult('a', self.repowatcher.statustrees['a']),
             genresult('r', self.repowatcher.statustrees['r']),
             genresult('!', self.repowatcher.statustrees['!']),
             '?' in states
                 and genresult('?', self.repowatcher.statustrees['?'])
                 or [],
             [],
             'c' in states and genresult('n', self.repowatcher.tree) or [],
             visited
             ]]
 
     def answer_dbug_query(self):
         return ['\0'.join(self.repowatcher.debug())]
 
     def handle_pollevents(self, events):
         for e in events:
             self.handle_pollevent()
 
     def handle_pollevent(self):
         sock, addr = self.sock.accept()
 
         cs = common.recvcs(sock)
         version = ord(cs.read(1))
 
         if version != common.version:
             self.ui.warn(_('received query from incompatible client '
                            'version %d\n') % version)
             try:
                 # try to send back our version to the client
                 # this way, the client too is informed of the mismatch
                 sock.sendall(chr(common.version))
             except:
                 pass
             return
 
         type = cs.read(4)
 
         if type == 'STAT':
             results = self.answer_stat_query(cs)
         elif type == 'DBUG':
             results = self.answer_dbug_query()
         else:
             self.ui.warn(_('unrecognized query type: %s\n') % type)
             return
 
         try:
             try:
                 v = chr(common.version)
 
                 sock.sendall(v + type + struct.pack(common.resphdrfmts[type],
                                             *map(len, results)))
                 sock.sendall(''.join(results))
             finally:
                 sock.shutdown(socket.SHUT_WR)
         except socket.error, err:
             if err[0] != errno.EPIPE:
                 raise
 
     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
 
 class master(object):
     def __init__(self, ui, dirstate, root, timeout=None):
         self.ui = ui
         self.repowatcher = repowatcher(ui, dirstate, root)
         self.server = server(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()
 
 def start(ui, dirstate, root, opts):
     timeout = opts.get('timeout')
     if timeout:
         timeout = float(timeout) * 1e3
 
     class service(object):
         def init(self):
             try:
                 self.master = master(ui, dirstate, root, timeout)
             except AlreadyStartedException, inst:
-                raise util.Abort(str(inst))
+                raise util.Abort("inotify-server: %s" % inst)
 
         def run(self):
             try:
                 self.master.run()
             finally:
                 self.master.shutdown()
 
     if 'inserve' not in sys.argv:
         runargs = [sys.argv[0], 'inserve', '-R', root]
     else:
         runargs = sys.argv[:]
 
     pidfile = ui.config('inotify', 'pidfile')
     if opts['daemon'] and pidfile is not None and 'pid-file' not in runargs:
         runargs.append("--pid-file=%s" % pidfile)
 
     service = service()
     logfile = ui.config('inotify', 'log')
     cmdutil.service(opts, initfn=service.init, runfn=service.run,
                     logfile=logfile, runargs=runargs)

tests/test-inotify

@@ -1,96 +1,100
 #!/bin/sh
 
 "$TESTDIR/hghave" inotify || exit 80
 
 hg init repo1
 cd repo1
 
 touch a b c d e
 mkdir dir
 mkdir dir/bar
 touch dir/x dir/y dir/bar/foo
 
 hg ci -Am m
 cd ..
 hg clone repo1 repo2
 
 echo "[extensions]" >> $HGRCPATH
 echo "inotify=" >> $HGRCPATH
 
 cd repo2
 echo b >> a
 # check that daemon started automatically works correctly
 # and make sure that inotify.pidfile works
 hg --config "inotify.pidfile=../hg2.pid" status
 
 # make sure that pidfile worked. Output should be silent.
 kill `cat ../hg2.pid`
 
 cd ../repo1
 echo % inserve
 hg inserve -d --pid-file=hg.pid
 cat hg.pid >> "$DAEMON_PIDS"
 
 # let the daemon finish its stuff
 sleep 1
+
+echo % cannot start, already bound
+hg inserve
+
 # issue907
 hg status
 echo % clean
 hg status -c
 echo % all
 hg status -A
 
 echo '% path patterns'
 echo x > dir/x
 hg status .
 hg status dir
 cd dir
 hg status .
 cd ..
 
 #issue 1375
 #Testing that we can remove a folder and then add a file with the same name
 echo % issue 1375
 
 mkdir h
 echo h > h/h
 hg ci -Am t
 hg rm h
 
 echo h >h
 hg add h
 
 hg status
 hg ci -m0
 
 # Test for issue1735: inotify watches files in .hg/merge
 hg st
 
 echo a > a
 
 hg ci -Am a
 hg st
 
 echo b >> a
 hg ci -m ab
 hg st
 
 echo c >> a
 hg st
 
 hg up 0
 hg st
 
 HGMERGE=internal:local hg up
 hg st
 
 # Test for 1844: "hg ci folder" will not commit all changes beneath "folder"
 mkdir 1844
 echo a > 1844/foo
 hg add 1844
 hg ci -m 'working'
 
 echo b >> 1844/foo
 hg ci 1844 -m 'broken'
 
 kill `cat hg.pid`

tests/test-inotify-issue1208.out

@@ -1,7 +1,7
 % fail
-abort: could not start server: File exists
-could not talk to new inotify server: No such file or directory
-abort: could not start server: File exists
+abort: inotify-server: cannot start: .hg/inotify.sock is a broken symlink
+inotify-client: could not talk to new inotify server: No such file or directory
+abort: inotify-server: cannot start: .hg/inotify.sock is a broken symlink
 % inserve
 % status
 ? hg.pid

tests/test-inotify.out

@@ -1,50 +1,52
 adding a
 adding b
 adding c
 adding d
 adding dir/bar/foo
 adding dir/x
 adding dir/y
 adding e
 updating to branch default
 8 files updated, 0 files merged, 0 files removed, 0 files unresolved
 M a
 % inserve
+% cannot start, already bound
+abort: inotify-server: cannot start: socket is already bound
 ? hg.pid
 % clean
 C a
 C b
 C c
 C d
 C dir/bar/foo
 C dir/x
 C dir/y
 C e
 % all
 ? hg.pid
 C a
 C b
 C c
 C d
 C dir/bar/foo
 C dir/x
 C dir/y
 C e
 % path patterns
 M dir/x
 ? hg.pid
 M dir/x
 M x
 % issue 1375
 adding h/h
 adding hg.pid
 removing h/h
 A h
 R h/h
 M a
 merging a
 1 files updated, 1 files merged, 2 files removed, 0 files unresolved
 M a
 3 files updated, 1 files merged, 0 files removed, 0 files unresolved
 M a
 adding 1844/foo