From 236d70ce2c5e56d89a88f1ef9eeec8180561fbcd Mon Sep 17 00:00:00 2001 From: Antoine Pitrou Date: Wed, 2 Nov 2016 00:41:05 +0100 Subject: [PATCH] Fix freezing the SSL write buffer --- tornado/iostream.py | 48 ++++++++++++++++++++++++++++++++------------- 1 file changed, 34 insertions(+), 14 deletions(-) diff --git a/tornado/iostream.py b/tornado/iostream.py index 05ddef0bd..54b6382a9 100644 --- a/tornado/iostream.py +++ b/tornado/iostream.py @@ -167,6 +167,7 @@ class BaseIOStream(object): self._write_buffer_pos = 0 self._write_buffer_size = 0 self._write_buffer_frozen = False + self._pending_writes_while_frozen = [] self._read_delimiter = None self._read_regex = None self._read_max_bytes = None @@ -382,8 +383,11 @@ class BaseIOStream(object): if (self.max_write_buffer_size is not None and self._write_buffer_size + len(data) > self.max_write_buffer_size): raise StreamBufferFullError("Reached maximum write buffer size") - self._write_buffer += data - self._write_buffer_size += len(data) + if self._write_buffer_frozen: + self._pending_writes_while_frozen.append(data) + else: + self._write_buffer += data + self._write_buffer_size += len(data) if callback is not None: self._write_callback = stack_context.wrap(callback) future = None @@ -816,8 +820,21 @@ class BaseIOStream(object): "delimiter %r not found within %d bytes" % ( delimiter, self._read_max_bytes)) + def _freeze_write_buffer(self, size): + self._write_buffer_frozen = size + + def _unfreeze_write_buffer(self): + self._write_buffer_frozen = False + self._write_buffer += b''.join(self._pending_writes_while_frozen) + self._write_buffer_size += sum(map(len, self._pending_writes_while_frozen)) + self._pending_writes_while_frozen[:] = [] + + def _got_empty_write(self, size): + pass + def _handle_write(self): while self._write_buffer_size: + assert self._write_buffer_size >= 0 try: start = self._write_buffer_pos if self._write_buffer_frozen: @@ -833,28 +850,20 @@ class BaseIOStream(object): size = self._write_buffer_size num_bytes = self.write_to_fd( memoryview(self._write_buffer)[start:start + size]) - assert self._write_buffer_size >= 0 if num_bytes == 0: - # With OpenSSL, if we couldn't write the entire buffer, - # the very same string object must be used on the - # next call to send. Therefore we suppress - # merging the write buffer after an incomplete send. - # A cleaner solution would be to set - # SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER, but this is - # not yet accessible from python - # (http://bugs.python.org/issue8240) - self._write_buffer_frozen = size + self._got_empty_write(size) break - self._write_buffer_frozen = False self._write_buffer_pos += num_bytes self._write_buffer_size -= num_bytes # Amortized O(1) shrink if self._write_buffer_pos > self._write_buffer_size: del self._write_buffer[:self._write_buffer_pos] self._write_buffer_pos = 0 + if self._write_buffer_frozen: + self._unfreeze_write_buffer() except (socket.error, IOError, OSError) as e: if e.args[0] in _ERRNO_WOULDBLOCK: - self._write_buffer_frozen = size + self._got_empty_write(size) break else: if not self._is_connreset(e): @@ -1263,6 +1272,17 @@ class SSLIOStream(IOStream): def writing(self): return self._handshake_writing or super(SSLIOStream, self).writing() + def _got_empty_write(self, size): + # With OpenSSL, if we couldn't write the entire buffer, + # the very same string object must be used on the + # next call to send. Therefore we suppress + # merging the write buffer after an incomplete send. + # A cleaner solution would be to set + # SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER, but this is + # not yet accessible from python + # (http://bugs.python.org/issue8240) + self._freeze_write_buffer(size) + def _do_ssl_handshake(self): # Based on code from test_ssl.py in the python stdlib try: -- 2.47.2