diff options
| -rw-r--r-- | src/backend/port/win32/socket.c | 28 | ||||
| -rw-r--r-- | src/backend/storage/ipc/latch.c | 32 |
2 files changed, 44 insertions, 16 deletions
diff --git a/src/backend/port/win32/socket.c b/src/backend/port/win32/socket.c index a6f9070761a..f11d6e6eb86 100644 --- a/src/backend/port/win32/socket.c +++ b/src/backend/port/win32/socket.c @@ -523,11 +523,16 @@ pgwin32_select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, c FD_ZERO(&outwritefds); /* - * Write FDs are different in the way that it is only flagged by - * WSASelectEvent() if we have tried to write to them first. So try an - * empty write + * Windows does not guarantee to log an FD_WRITE network event indicating + * that more data can be sent unless the previous send() failed with + * WSAEWOULDBLOCK. While our caller might well have made such a call, we + * cannot assume that here. Therefore, if waiting for write-ready, force + * the issue by doing a dummy send(). If the dummy send() succeeds, + * assume that the socket is in fact write-ready, and return immediately. + * Also, if it fails with something other than WSAEWOULDBLOCK, return a + * write-ready indication to let our caller deal with the error condition. */ - if (writefds) + if (writefds != NULL) { for (i = 0; i < writefds->fd_count; i++) { @@ -539,20 +544,11 @@ pgwin32_select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, c buf.len = 0; r = WSASend(writefds->fd_array[i], &buf, 1, &sent, 0, NULL, NULL); - if (r == 0) /* Completed - means things are fine! */ + if (r == 0 || WSAGetLastError() != WSAEWOULDBLOCK) FD_SET(writefds->fd_array[i], &outwritefds); - - else - { /* Not completed */ - if (WSAGetLastError() != WSAEWOULDBLOCK) - - /* - * Not completed, and not just "would block", so an error - * occurred - */ - FD_SET(writefds->fd_array[i], &outwritefds); - } } + + /* If we found any write-ready sockets, just return them immediately */ if (outwritefds.fd_count > 0) { memcpy(writefds, &outwritefds, sizeof(fd_set)); diff --git a/src/backend/storage/ipc/latch.c b/src/backend/storage/ipc/latch.c index ea7f930866f..47983704d7e 100644 --- a/src/backend/storage/ipc/latch.c +++ b/src/backend/storage/ipc/latch.c @@ -1401,6 +1401,38 @@ WaitEventSetWaitBlock(WaitEventSet *set, int cur_timeout, WaitEventAdjustWin32(set, cur_event); cur_event->reset = false; } + + /* + * Windows does not guarantee to log an FD_WRITE network event + * indicating that more data can be sent unless the previous send() + * failed with WSAEWOULDBLOCK. While our caller might well have made + * such a call, we cannot assume that here. Therefore, if waiting for + * write-ready, force the issue by doing a dummy send(). If the dummy + * send() succeeds, assume that the socket is in fact write-ready, and + * return immediately. Also, if it fails with something other than + * WSAEWOULDBLOCK, return a write-ready indication to let our caller + * deal with the error condition. + */ + if (cur_event->events & WL_SOCKET_WRITEABLE) + { + char c; + WSABUF buf; + DWORD sent; + int r; + + buf.buf = &c; + buf.len = 0; + + r = WSASend(cur_event->fd, &buf, 1, &sent, 0, NULL, NULL); + if (r == 0 || WSAGetLastError() != WSAEWOULDBLOCK) + { + occurred_events->pos = cur_event->pos; + occurred_events->user_data = cur_event->user_data; + occurred_events->events = WL_SOCKET_WRITEABLE; + occurred_events->fd = cur_event->fd; + return 1; + } + } } /* |