import os import sys import pwd import time import fcntl import shutil import logging import socket from threading import Lock, Thread as baseThread from errno import EACCES, EAGAIN, EPIPE, ENOTCONN, ECONNABORTED, EINTR, ENOENT, EPERM, ESTALE, errorcode from signal import signal, SIGTERM, SIGKILL from time import sleep import select as oselect from os import waitpid as owaitpid try: from cPickle import PickleError except ImportError: # py 3 from pickle import PickleError from gconf import gconf try: # py 3 from urllib import parse as urllib except ImportError: import urllib try: from hashlib import md5 as md5 except ImportError: # py 2.4 from md5 import new as md5 # auxillary gfid based access prefix _CL_AUX_GFID_PFX = ".gfid/" GF_OP_RETRIES = 20 def escape(s): """the chosen flavor of string escaping, used all over to turn whatever data to creatable representation""" return urllib.quote_plus(s) def unescape(s): """inverse of .escape""" return urllib.unquote_plus(s) def norm(s): if s: return s.replace('-', '_') def update_file(path, updater, merger = lambda f: True): """update a file in a transaction-like manner""" fr = fw = None try: fd = os.open(path, os.O_CREAT|os.O_RDWR) try: fr = os.fdopen(fd, 'r+b') except: os.close(fd) raise fcntl.lockf(fr, fcntl.LOCK_EX) if not merger(fr): return tmpp = path + '.tmp.' + str(os.getpid()) fd = os.open(tmpp, os.O_CREAT|os.O_EXCL|os.O_WRONLY) try: fw = os.fdopen(fd, 'wb', 0) except: os.close(fd) raise updater(fw) os.fsync(fd) os.rename(tmpp, path) finally: for fx in (fr, fw): if fx: fx.close() def create_manifest(fname, content): """ Create manifest file for SSH Control Path """ fd = None try: fd = os.open(fname, os.O_CREAT|os.O_RDWR) try: os.write(fd, content) except: os.close(fd) raise finally: if fd != None: os.close(fd) def setup_ssh_ctl(ctld, remote_addr, resource_url): """ Setup GConf ssh control path parameters """ gconf.ssh_ctl_dir = ctld content = "SLAVE_HOST=%s\nSLAVE_RESOURCE_URL=%s" % (remote_addr, resource_url) content_md5 = md5hex(content) fname = os.path.join(gconf.ssh_ctl_dir, "%s.mft" % content_md5) create_manifest(fname, content) ssh_ctl_path = os.path.join(gconf.ssh_ctl_dir, "%s.sock" % content_md5) gconf.ssh_ctl_args = ["-oControlMaster=auto", "-S", ssh_ctl_path] def grabfile(fname, content=None): """open @fname + contest for its fcntl lock @content: if given, set the file content to it """ # damn those messy open() mode codes fd = os.open(fname, os.O_CREAT|os.O_RDWR) f = os.fdopen(fd, 'r+b', 0) try: fcntl.lockf(f, fcntl.LOCK_EX|fcntl.LOCK_NB) except: ex = sys.exc_info()[1] f.close() if isinstance(ex, IOError) and ex.errno in (EACCES, EAGAIN): # cannot grab, it's taken return raise if content: try: f.truncate() f.write(content) except: f.close() raise gconf.permanent_handles.append(f) return f def grabpidfile(fname=None, setpid=True): """.grabfile customization for pid files""" if not fname: fname = gconf.pid_file content = None if setpid: content = str(os.getpid()) + '\n' return grabfile(fname, content=content) final_lock = Lock() def finalize(*a, **kw): """all those messy final steps we go trough upon termination Do away with pidfile, ssh control dir and logging. """ final_lock.acquire() if getattr(gconf, 'pid_file', None): rm_pidf = gconf.pid_file_owned if gconf.cpid: # exit path from parent branch of daemonization rm_pidf = False while True: f = grabpidfile(setpid=False) if not f: # child has already taken over pidfile break if os.waitpid(gconf.cpid, os.WNOHANG)[0] == gconf.cpid: # child has terminated rm_pidf = True break; time.sleep(0.1) if rm_pidf: try: os.unlink(gconf.pid_file) except: ex = sys.exc_info()[1] if ex.errno == ENOENT: pass else: raise if gconf.ssh_ctl_dir and not gconf.cpid: shutil.rmtree(gconf.ssh_ctl_dir) if getattr(gconf, 'state_socket', None): try: os.unlink(gconf.state_socket) except: if sys.exc_info()[0] == OSError: pass if gconf.log_exit: logging.info("exiting.") sys.stdout.flush() sys.stderr.flush() os._exit(kw.get('exval', 0)) def log_raise_exception(excont): """top-level exception handler Try to some fancy things to cover up we face with an error. Translate some weird sounding but well understood exceptions into human-friendly lingo """ is_filelog = False for h in logging.getLogger().handlers: fno = getattr(getattr(h, 'stream', None), 'fileno', None) if fno and not os.isatty(fno()): is_filelog = True exc = sys.exc_info()[1] if isinstance(exc, SystemExit): excont.exval = exc.code or 0 raise else: logtag = None if isinstance(exc, GsyncdError): if is_filelog: logging.error(exc.args[0]) sys.stderr.write('failure: ' + exc.args[0] + '\n') elif isinstance(exc, PickleError) or isinstance(exc, EOFError) or \ ((isinstance(exc, OSError) or isinstance(exc, IOError)) and \ exc.errno == EPIPE): logging.error('connection to peer is broken') if hasattr(gconf, 'transport'): gconf.transport.wait() if gconf.transport.returncode == 127: logging.warn("!!!!!!!!!!!!!") logging.warn('!!! getting "No such file or directory" errors ' "is most likely due to MISCONFIGURATION, please consult " "http://access.redhat.com/knowledge/docs/en-US/Red_Hat_Storage/2.0/html/Administration_Guide/chap-User_Guide-Geo_Rep-Preparation-Settingup_Environment.html") logging.warn("!!!!!!!!!!!!!") gconf.transport.terminate_geterr() elif isinstance(exc, OSError) and exc.errno in (ENOTCONN, ECONNABORTED): logging.error('glusterfs session went down [%s]', errorcode[exc.errno]) else: logtag = "FAIL" if not logtag and logging.getLogger().isEnabledFor(logging.DEBUG): logtag = "FULL EXCEPTION TRACE" if logtag: logging.exception(logtag + ": ") sys.stderr.write("failed with %s.\n" % type(exc).__name__) excont.exval = 1 sys.exit(excont.exval) class FreeObject(object): """wildcard class for which any attribute can be set""" def __init__(self, **kw): for k,v in kw.items(): setattr(self, k, v) class Thread(baseThread): """thread class flavor for gsyncd - always a daemon thread - force exit for whole program if thread function coughs up an exception """ def __init__(self, *a, **kw): tf = kw.get('target') if tf: def twrap(*aa): excont = FreeObject(exval = 0) try: tf(*aa) except: try: log_raise_exception(excont) finally: finalize(exval = excont.exval) kw['target'] = twrap baseThread.__init__(self, *a, **kw) self.setDaemon(True) class GsyncdError(Exception): pass def getusername(uid = None): if uid == None: uid = os.geteuid() return pwd.getpwuid(uid).pw_name def privileged(): return os.geteuid() == 0 def boolify(s): """ Generic string to boolean converter return - Quick return if string 's' is of type bool - True if it's in true_list - False if it's in false_list - Warn if it's not present in either and return False """ true_list = ['true', 'yes', '1', 'on'] false_list = ['false', 'no', '0', 'off'] if isinstance(s, bool): return s rv = False lstr = s.lower() if lstr in true_list: rv = True elif not lstr in false_list: logging.warn("Unknown string (%s) in string to boolean conversion defaulting to False\n" % (s)) return rv def eintr_wrap(func, exc, *a): """ wrapper around syscalls resilient to interrupt caused by signals """ while True: try: return func(*a) except exc: ex = sys.exc_info()[1] if not ex.args[0] == EINTR: raise def select(*a): return eintr_wrap(oselect.select, oselect.error, *a) def waitpid (*a): return eintr_wrap(owaitpid, OSError, *a) def set_term_handler(hook=lambda *a: finalize(*a, **{'exval': 1})): signal(SIGTERM, hook) def is_host_local(host): locaddr = False for ai in socket.getaddrinfo(host, None): # cf. http://github.com/gluster/glusterfs/blob/ce111f47/xlators/mgmt/glusterd/src/glusterd-utils.c#L125 if ai[0] == socket.AF_INET: if ai[-1][0].split(".")[0] == "127": locaddr = True break elif ai[0] == socket.AF_INET6: if ai[-1][0] == "::1": locaddr = True break else: continue try: # use ICMP socket to avoid net.ipv4.ip_nonlocal_bind issue, # cf. https://bugzilla.redhat.com/show_bug.cgi?id=890587 s = socket.socket(ai[0], socket.SOCK_RAW, socket.IPPROTO_ICMP) except socket.error: ex = sys.exc_info()[1] if ex.errno != EPERM: raise f = None try: f = open("/proc/sys/net/ipv4/ip_nonlocal_bind") if int(f.read()) != 0: raise GsyncdError( "non-local bind is set and not allowed to create raw sockets, " "cannot determine if %s is local" % host) s = socket.socket(ai[0], socket.SOCK_DGRAM) finally: if f: f.close() try: s.bind(ai[-1]) locaddr = True break except: pass s.close() return locaddr def funcode(f): fc = getattr(f, 'func_code', None) if not fc: # python 3 fc = f.__code__ return fc def memoize(f): fc = funcode(f) fn = fc.co_name def ff(self, *a, **kw): rv = getattr(self, '_' + fn, None) if rv == None: rv = f(self, *a, **kw) setattr(self, '_' + fn, rv) return rv return ff def umask(): return os.umask(0) def entry2pb(e): return e.rsplit('/', 1) def gauxpfx(): return _CL_AUX_GFID_PFX def md5hex(s): return md5(s).hexdigest() def selfkill(sig=SIGTERM): os.kill(os.getpid(), sig) def errno_wrap(call, arg=[], errnos=[], retry_errnos=[ESTALE]): """ wrapper around calls resilient to errnos. retry in case of ESTALE by default. """ nr_tries = 0 while True: try: return call(*arg) except OSError: ex = sys.exc_info()[1] if ex.errno in errnos: return ex.errno if not ex.errno in retry_errnos: raise nr_tries += 1 if nr_tries == GF_OP_RETRIES: # probably a screwed state, cannot do much... logging.warn('reached maximum retries (%s)...' % repr(arg)) return time.sleep(0.250) # retry the call def lstat(e): try: return os.lstat(e) except (IOError, OSError): ex = sys.exc_info()[1] if ex.errno == ENOENT: return ex.errno else: raise