bpo-39259: ftplib.FTP/FTP_TLS now reject timeout = 0 (GH-17959)
diff --git a/Doc/library/ftplib.rst b/Doc/library/ftplib.rst
index 79a0286..a4bb695 100644
--- a/Doc/library/ftplib.rst
+++ b/Doc/library/ftplib.rst
@@ -72,6 +72,9 @@
.. versionchanged:: 3.3
*source_address* parameter was added.
+ .. versionchanged:: 3.9
+ If the *timeout* parameter is set to be zero, it will raise a
+ :class:`ValueError` to prevent the creation of a non-blocking socket
.. class:: FTP_TLS(host='', user='', passwd='', acct='', keyfile=None, certfile=None, context=None, timeout=None, source_address=None)
@@ -105,6 +108,10 @@
:func:`ssl.create_default_context` select the system's trusted CA
certificates for you.
+ .. versionchanged:: 3.9
+ If the *timeout* parameter is set to be zero, it will raise a
+ :class:`ValueError` to prevent the creation of a non-blocking socket
+
Here's a sample session using the :class:`FTP_TLS` class::
>>> ftps = FTP_TLS('ftp.pureftpd.org')
diff --git a/Doc/whatsnew/3.9.rst b/Doc/whatsnew/3.9.rst
index b6ffa23..859bf44 100644
--- a/Doc/whatsnew/3.9.rst
+++ b/Doc/whatsnew/3.9.rst
@@ -159,6 +159,13 @@
and :data:`~fcntl.F_OFD_SETLKW`.
(Contributed by Dong-hee Na in :issue:`38602`.)
+ftplib
+-------
+
+:class:`~ftplib.FTP` and :class:`~ftplib.FTP_TLS` now raise a :class:`ValueError`
+if the given timeout for their constructor is zero to prevent the creation of
+a non-blocking socket. (Contributed by Dong-hee Na in :issue:`39259`.)
+
gc
--
diff --git a/Lib/ftplib.py b/Lib/ftplib.py
index c339eb2..71b3c28 100644
--- a/Lib/ftplib.py
+++ b/Lib/ftplib.py
@@ -146,6 +146,8 @@
self.port = port
if timeout != -999:
self.timeout = timeout
+ if self.timeout is not None and not self.timeout:
+ raise ValueError('Non-blocking socket (timeout=0) is not supported')
if source_address is not None:
self.source_address = source_address
sys.audit("ftplib.connect", self, self.host, self.port)
@@ -725,12 +727,12 @@
keyfile=keyfile)
self.context = context
self._prot_p = False
- FTP.__init__(self, host, user, passwd, acct, timeout, source_address)
+ super().__init__(host, user, passwd, acct, timeout, source_address)
def login(self, user='', passwd='', acct='', secure=True):
if secure and not isinstance(self.sock, ssl.SSLSocket):
self.auth()
- return FTP.login(self, user, passwd, acct)
+ return super().login(user, passwd, acct)
def auth(self):
'''Set up secure control connection by using TLS/SSL.'''
@@ -740,8 +742,7 @@
resp = self.voidcmd('AUTH TLS')
else:
resp = self.voidcmd('AUTH SSL')
- self.sock = self.context.wrap_socket(self.sock,
- server_hostname=self.host)
+ self.sock = self.context.wrap_socket(self.sock, server_hostname=self.host)
self.file = self.sock.makefile(mode='r', encoding=self.encoding)
return resp
@@ -778,7 +779,7 @@
# --- Overridden FTP methods
def ntransfercmd(self, cmd, rest=None):
- conn, size = FTP.ntransfercmd(self, cmd, rest)
+ conn, size = super().ntransfercmd(cmd, rest)
if self._prot_p:
conn = self.context.wrap_socket(conn,
server_hostname=self.host)
diff --git a/Lib/test/test_ftplib.py b/Lib/test/test_ftplib.py
index 62f673c..f40f3a4 100644
--- a/Lib/test/test_ftplib.py
+++ b/Lib/test/test_ftplib.py
@@ -1045,6 +1045,10 @@
self.evt.wait()
ftp.close()
+ # bpo-39259
+ with self.assertRaises(ValueError):
+ ftplib.FTP(HOST, timeout=0)
+
def testTimeoutConnect(self):
ftp = ftplib.FTP()
ftp.connect(HOST, timeout=30)
diff --git a/Misc/NEWS.d/next/Library/2020-01-12-17-19-40.bpo-39259.iax06r.rst b/Misc/NEWS.d/next/Library/2020-01-12-17-19-40.bpo-39259.iax06r.rst
new file mode 100644
index 0000000..bfcaff3
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2020-01-12-17-19-40.bpo-39259.iax06r.rst
@@ -0,0 +1,3 @@
+:class:`~ftplib.FTP_TLS` and :class:`~ftplib.FTP_TLS` now raise a
+:class:`ValueError` if the given timeout for their constructor is zero to
+prevent the creation of a non-blocking socket. Patch by Dong-hee Na.