Merge with Python 3.4 (asyncio)

- Close #22063: socket operations (socket,recv, sock_sendall, sock_connect,
  sock_accept) now raise an exception in debug mode if sockets are in blocking
  mode.
- asyncio: Use the new os.set_blocking() function of Python 3.5 if available

Lib/asyncio/proactor_events.py

@@ -385,12 +385,18 @@ class BaseProactorEventLoop(base_events.BaseEventLoop):
         self._selector = None
 
     def sock_recv(self, sock, n):
+        if self.get_debug() and sock.gettimeout() != 0:
+            raise ValueError("the socket must be non-blocking")
         return self._proactor.recv(sock, n)
 
     def sock_sendall(self, sock, data):
+        if self.get_debug() and sock.gettimeout() != 0:
+            raise ValueError("the socket must be non-blocking")
         return self._proactor.send(sock, data)
 
     def sock_connect(self, sock, address):
+        if self.get_debug() and sock.gettimeout() != 0:
+            raise ValueError("the socket must be non-blocking")
         try:
             base_events._check_resolved_address(sock, address)
         except ValueError as err:
@@ -401,6 +407,8 @@ class BaseProactorEventLoop(base_events.BaseEventLoop):
             return self._proactor.connect(sock, address)
 
     def sock_accept(self, sock):
+        if self.get_debug() and sock.gettimeout() != 0:
+            raise ValueError("the socket must be non-blocking")
         return self._proactor.accept(sock)
 
     def _socketpair(self):

Lib/asyncio/selector_events.py

@@ -256,6 +256,8 @@ class BaseSelectorEventLoop(base_events.BaseEventLoop):
 
         This method is a coroutine.
         """
+        if self.get_debug() and sock.gettimeout() != 0:
+            raise ValueError("the socket must be non-blocking")
         fut = futures.Future(loop=self)
         self._sock_recv(fut, False, sock, n)
         return fut
@@ -292,6 +294,8 @@ class BaseSelectorEventLoop(base_events.BaseEventLoop):
 
         This method is a coroutine.
         """
+        if self.get_debug() and sock.gettimeout() != 0:
+            raise ValueError("the socket must be non-blocking")
         fut = futures.Future(loop=self)
         if data:
             self._sock_sendall(fut, False, sock, data)
@@ -333,6 +337,8 @@ class BaseSelectorEventLoop(base_events.BaseEventLoop):
 
         This method is a coroutine.
         """
+        if self.get_debug() and sock.gettimeout() != 0:
+            raise ValueError("the socket must be non-blocking")
         fut = futures.Future(loop=self)
         try:
             base_events._check_resolved_address(sock, address)
@@ -374,6 +380,8 @@ class BaseSelectorEventLoop(base_events.BaseEventLoop):
 
         This method is a coroutine.
         """
+        if self.get_debug() and sock.gettimeout() != 0:
+            raise ValueError("the socket must be non-blocking")
         fut = futures.Future(loop=self)
         self._sock_accept(fut, False, sock)
         return fut

Lib/asyncio/unix_events.py

@@ -258,6 +258,16 @@ class _UnixSelectorEventLoop(selector_events.BaseSelectorEventLoop):
         return server
 
 
+if hasattr(os, 'set_blocking'):
+    def _set_nonblocking(fd):
+        os.set_blocking(fd, False)
+else:
+    def _set_nonblocking(fd):
+        flags = fcntl.fcntl(fd, fcntl.F_GETFL)
+        flags = flags | os.O_NONBLOCK
+        fcntl.fcntl(fd, fcntl.F_SETFL, flags)
+
+
 class _UnixReadPipeTransport(transports.ReadTransport):
 
     max_size = 256 * 1024  # max bytes we read in one event loop iteration
@@ -273,7 +283,7 @@ class _UnixReadPipeTransport(transports.ReadTransport):
                 stat.S_ISSOCK(mode) or
                 stat.S_ISCHR(mode)):
             raise ValueError("Pipe transport is for pipes/sockets only.")
-        os.set_blocking(self._fileno, False)
+        _set_nonblocking(self._fileno)
         self._protocol = protocol
         self._closing = False
         self._loop.add_reader(self._fileno, self._read_ready)
@@ -366,7 +376,7 @@ class _UnixWritePipeTransport(transports._FlowControlMixin,
                 stat.S_ISCHR(mode)):
             raise ValueError("Pipe transport is only for "
                              "pipes, sockets and character devices")
-        os.set_blocking(self._fileno, False)
+        _set_nonblocking(self._fileno)
         self._protocol = protocol
         self._buffer = []
         self._conn_lost = 0