Issue #9950: Fix socket.sendall() crash or misbehaviour when a signal is
received. Now sendall() properly calls signal handlers if necessary,
and retries sending if these returned successfully, including on sockets
with a timeout.
diff --git a/Modules/socketmodule.c b/Modules/socketmodule.c
index 6ebb9d9..cd56ee3 100644
--- a/Modules/socketmodule.c
+++ b/Modules/socketmodule.c
@@ -2568,7 +2568,7 @@
{
char *buf;
Py_ssize_t len, n = -1;
- int flags = 0, timeout;
+ int flags = 0, timeout, saved_errno;
Py_buffer pbuf;
if (!PyArg_ParseTuple(args, "y*|i:sendall", &pbuf, &flags))
@@ -2581,42 +2581,44 @@
return select_error();
}
- Py_BEGIN_ALLOW_THREADS
do {
+ Py_BEGIN_ALLOW_THREADS
timeout = internal_select(s, 1);
n = -1;
- if (timeout)
- break;
+ if (!timeout) {
#ifdef __VMS
- n = sendsegmented(s->sock_fd, buf, len, flags);
+ n = sendsegmented(s->sock_fd, buf, len, flags);
#else
- n = send(s->sock_fd, buf, len, flags);
+ n = send(s->sock_fd, buf, len, flags);
#endif
+ }
+ Py_END_ALLOW_THREADS
+ if (timeout == 1) {
+ PyBuffer_Release(&pbuf);
+ PyErr_SetString(socket_timeout, "timed out");
+ return NULL;
+ }
+ /* PyErr_CheckSignals() might change errno */
+ saved_errno = errno;
+ /* We must run our signal handlers before looping again.
+ send() can return a successful partial write when it is
+ interrupted, so we can't restrict ourselves to EINTR. */
+ if (PyErr_CheckSignals()) {
+ PyBuffer_Release(&pbuf);
+ return NULL;
+ }
if (n < 0) {
-#ifdef EINTR
- /* We must handle EINTR here as there is no way for
- * the caller to know how much was sent otherwise. */
- if (errno == EINTR) {
- /* Run signal handlers. If an exception was
- * raised, abort and leave this socket in
- * an unknown state. */
- if (PyErr_CheckSignals())
- return NULL;
+ /* If interrupted, try again */
+ if (saved_errno == EINTR)
continue;
- }
-#endif
- break;
+ else
+ break;
}
buf += n;
len -= n;
} while (len > 0);
- Py_END_ALLOW_THREADS
PyBuffer_Release(&pbuf);
- if (timeout == 1) {
- PyErr_SetString(socket_timeout, "timed out");
- return NULL;
- }
if (n < 0)
return s->errorhandler();