import logging
import logging.handlers
import signal
+import datetime
+import calendar
from cStringIO import StringIO
# as efficient.
if mkdir and err.errno == errno.ENOENT:
# Create directory and try again
- dirname = os.path.dirname(new)
- try:
- os.makedirs(dirname, mode=mkdir_mode)
- except OSError, err:
- # Ignore EEXIST. This is only handled in os.makedirs as included in
- # Python 2.5 and above.
- if err.errno != errno.EEXIST or not os.path.exists(dirname):
- raise
+ Makedirs(os.path.dirname(new), mode=mkdir_mode)
return os.rename(old, new)
raise
+def Makedirs(path, mode=0750):
+ """Super-mkdir; create a leaf directory and all intermediate ones.
+
+ This is a wrapper around C{os.makedirs} adding error handling not implemented
+ before Python 2.5.
+
+ """
+ try:
+ os.makedirs(path, mode)
+ except OSError, err:
+ # Ignore EEXIST. This is only handled in os.makedirs as included in
+ # Python 2.5 and above.
+ if err.errno != errno.EEXIST or not os.path.exists(path):
+ raise
+
+
def ResetTempfileModule():
"""Resets the random name generator of the tempfile module.
RemoveEtcHostsEntry(constants.ETC_HOSTS, hi.ShortName())
+def TimestampForFilename():
+ """Returns the current time formatted for filenames.
+
+ The format doesn't contain colons as some shells and applications them as
+ separators.
+
+ """
+ return time.strftime("%Y-%m-%d_%H_%M_%S")
+
+
def CreateBackup(file_name):
"""Creates a backup of a file.
raise errors.ProgrammerError("Can't make a backup of a non-file '%s'" %
file_name)
- prefix = '%s.backup-%d.' % (os.path.basename(file_name), int(time.time()))
+ prefix = ("%s.backup-%s." %
+ (os.path.basename(file_name), TimestampForFilename()))
dir_name = os.path.dirname(file_name)
fsrc = open(file_name, 'rb')
(fd, backup_name) = tempfile.mkstemp(prefix=prefix, dir=dir_name)
fdst = os.fdopen(fd, 'wb')
try:
+ logging.debug("Backing up %s at %s", file_name, backup_name)
shutil.copyfileobj(fsrc, fdst)
finally:
fdst.close()
return False
+def SingleWaitForFdCondition(fdobj, event, timeout):
+ """Waits for a condition to occur on the socket.
+
+ Immediately returns at the first interruption.
+
+ @type fdobj: integer or object supporting a fileno() method
+ @param fdobj: entity to wait for events on
+ @type event: integer
+ @param event: ORed condition (see select module)
+ @type timeout: float or None
+ @param timeout: Timeout in seconds
+ @rtype: int or None
+ @return: None for timeout, otherwise occured conditions
+
+ """
+ check = (event | select.POLLPRI |
+ select.POLLNVAL | select.POLLHUP | select.POLLERR)
+
+ if timeout is not None:
+ # Poller object expects milliseconds
+ timeout *= 1000
+
+ poller = select.poll()
+ poller.register(fdobj, event)
+ try:
+ # TODO: If the main thread receives a signal and we have no timeout, we
+ # could wait forever. This should check a global "quit" flag or something
+ # every so often.
+ io_events = poller.poll(timeout)
+ except select.error, err:
+ if err[0] != errno.EINTR:
+ raise
+ io_events = []
+ if io_events and io_events[0][1] & check:
+ return io_events[0][1]
+ else:
+ return None
+
+
+class FdConditionWaiterHelper(object):
+ """Retry helper for WaitForFdCondition.
+
+ This class contains the retried and wait functions that make sure
+ WaitForFdCondition can continue waiting until the timeout is actually
+ expired.
+
+ """
+
+ def __init__(self, timeout):
+ self.timeout = timeout
+
+ def Poll(self, fdobj, event):
+ result = SingleWaitForFdCondition(fdobj, event, self.timeout)
+ if result is None:
+ raise RetryAgain()
+ else:
+ return result
+
+ def UpdateTimeout(self, timeout):
+ self.timeout = timeout
+
+
+def WaitForFdCondition(fdobj, event, timeout):
+ """Waits for a condition to occur on the socket.
+
+ Retries until the timeout is expired, even if interrupted.
+
+ @type fdobj: integer or object supporting a fileno() method
+ @param fdobj: entity to wait for events on
+ @type event: integer
+ @param event: ORed condition (see select module)
+ @type timeout: float or None
+ @param timeout: Timeout in seconds
+ @rtype: int or None
+ @return: None for timeout, otherwise occured conditions
+
+ """
+ if timeout is not None:
+ retrywaiter = FdConditionWaiterHelper(timeout)
+ try:
+ result = Retry(retrywaiter.Poll, RETRY_REMAINING_TIME, timeout,
+ args=(fdobj, event), wait_fn=retrywaiter.UpdateTimeout)
+ except RetryTimeout:
+ result = None
+ else:
+ result = None
+ while result is None:
+ result = SingleWaitForFdCondition(fdobj, event, timeout)
+ return result
+
+
+def partition(seq, pred=bool): # # pylint: disable-msg=W0622
+ "Partition a list in two, based on the given predicate"
+ return (list(itertools.ifilter(pred, seq)),
+ list(itertools.ifilterfalse(pred, seq)))
+
+
def UniqueSequence(seq):
"""Returns a list with unique elements.
return rows[-lines:]
+def _ParseAsn1Generalizedtime(value):
+ """Parses an ASN1 GENERALIZEDTIME timestamp as used by pyOpenSSL.
+
+ @type value: string
+ @param value: ASN1 GENERALIZEDTIME timestamp
+
+ """
+ m = re.match(r"^(\d+)([-+]\d\d)(\d\d)$", value)
+ if m:
+ # We have an offset
+ asn1time = m.group(1)
+ hours = int(m.group(2))
+ minutes = int(m.group(3))
+ utcoffset = (60 * hours) + minutes
+ else:
+ if not value.endswith("Z"):
+ raise ValueError("Missing timezone")
+ asn1time = value[:-1]
+ utcoffset = 0
+
+ parsed = time.strptime(asn1time, "%Y%m%d%H%M%S")
+
+ tt = datetime.datetime(*(parsed[:7])) - datetime.timedelta(minutes=utcoffset)
+
+ return calendar.timegm(tt.utctimetuple())
+
+
+def GetX509CertValidity(cert):
+ """Returns the validity period of the certificate.
+
+ @type cert: OpenSSL.crypto.X509
+ @param cert: X509 certificate object
+
+ """
+ # The get_notBefore and get_notAfter functions are only supported in
+ # pyOpenSSL 0.7 and above.
+ try:
+ get_notbefore_fn = cert.get_notBefore
+ except AttributeError:
+ not_before = None
+ else:
+ not_before_asn1 = get_notbefore_fn()
+
+ if not_before_asn1 is None:
+ not_before = None
+ else:
+ not_before = _ParseAsn1Generalizedtime(not_before_asn1)
+
+ try:
+ get_notafter_fn = cert.get_notAfter
+ except AttributeError:
+ not_after = None
+ else:
+ not_after_asn1 = get_notafter_fn()
+
+ if not_after_asn1 is None:
+ not_after = None
+ else:
+ not_after = _ParseAsn1Generalizedtime(not_after_asn1)
+
+ return (not_before, not_after)
+
+
def SafeEncode(text):
"""Return a 'safe' version of a source string.
return (tsize, fsize)
-def RunInSeparateProcess(fn):
+def RunInSeparateProcess(fn, *args):
"""Runs a function in a separate process.
Note: Only boolean return values are supported.
@type fn: callable
@param fn: Function to be called
- @rtype: tuple of (int/None, int/None)
- @return: Exit code and signal number
+ @rtype: bool
+ @return: Function's result
"""
pid = os.fork()
ResetTempfileModule()
# Call function
- result = int(bool(fn()))
+ result = int(bool(fn(*args)))
assert result in (0, 1)
except: # pylint: disable-msg=W0702
logging.exception("Error while calling function in separate process")
return fn(*args)
except RetryAgain:
pass
+ except RetryTimeout:
+ raise errors.ProgrammerError("Nested retry loop detected that didn't"
+ " handle RetryTimeout")
remaining_time = end_time - _time_fn()
"""Utility class for file locks.
"""
- def __init__(self, filename):
+ def __init__(self, fd, filename):
"""Constructor for FileLock.
- This will open the file denoted by the I{filename} argument.
-
+ @type fd: file
+ @param fd: File object
@type filename: str
- @param filename: path to the file to be locked
+ @param filename: Path of the file opened at I{fd}
"""
+ self.fd = fd
self.filename = filename
- self.fd = open(self.filename, "w")
+
+ @classmethod
+ def Open(cls, filename):
+ """Creates and opens a file to be used as a file-based lock.
+
+ @type filename: string
+ @param filename: path to the file to be locked
+
+ """
+ # Using "os.open" is necessary to allow both opening existing file
+ # read/write and creating if not existing. Vanilla "open" will truncate an
+ # existing file -or- allow creating if not existing.
+ return cls(os.fdopen(os.open(filename, os.O_RDWR | os.O_CREAT), "w+"),
+ filename)
def __del__(self):
self.Close()
assert self.fd, "Lock was closed"
assert timeout is None or timeout >= 0, \
"If specified, timeout must be positive"
+ assert not (flag & fcntl.LOCK_NB), "LOCK_NB must not be set"
- if timeout is not None:
+ # When a timeout is used, LOCK_NB must always be set
+ if not (timeout is None and blocking):
flag |= fcntl.LOCK_NB
- timeout_end = time.time() + timeout
- # Blocking doesn't have effect with timeout
- elif not blocking:
- flag |= fcntl.LOCK_NB
- timeout_end = None
+ if timeout is None:
+ self._Lock(self.fd, flag, timeout)
+ else:
+ try:
+ Retry(self._Lock, (0.1, 1.2, 1.0), timeout,
+ args=(self.fd, flag, timeout))
+ except RetryTimeout:
+ raise errors.LockError(errmsg)
- # TODO: Convert to utils.Retry
+ @staticmethod
+ def _Lock(fd, flag, timeout):
+ try:
+ fcntl.flock(fd, flag)
+ except IOError, err:
+ if timeout is not None and err.errno == errno.EAGAIN:
+ raise RetryAgain()
- retry = True
- while retry:
- try:
- fcntl.flock(self.fd, flag)
- retry = False
- except IOError, err:
- if err.errno in (errno.EAGAIN, ):
- if timeout_end is not None and time.time() < timeout_end:
- # Wait before trying again
- time.sleep(max(0.1, min(1.0, timeout)))
- else:
- raise errors.LockError(errmsg)
- else:
- logging.exception("fcntl.flock failed")
- raise
+ logging.exception("fcntl.flock failed")
+ raise
def Exclusive(self, blocking=False, timeout=None):
"""Locks the file in exclusive mode.
projects / ganeti-local / blobdiff