qemu-coroutine-io: fix for Win32

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

nbd.c

@@ -156,7 +156,7 @@ ssize_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read)
             err = socket_error();
 
             /* recoverable error */
-            if (err == EINTR || (offset > 0 && err == EAGAIN)) {
+            if (err == EINTR || (offset > 0 && (err == EAGAIN || err == EWOULDBLOCK))) {
                 continue;
             }
 

qemu-coroutine-io.c

@@ -34,13 +34,15 @@ qemu_co_sendv_recvv(int sockfd, struct iovec *iov, unsigned iov_cnt,
 {
     size_t done = 0;
     ssize_t ret;
+    int err;
     while (done < bytes) {
         ret = iov_send_recv(sockfd, iov, iov_cnt,
                             offset + done, bytes - done, do_send);
         if (ret > 0) {
             done += ret;
         } else if (ret < 0) {
-            if (errno == EAGAIN) {
+            err = socket_error();
+            if (err == EAGAIN || err == EWOULDBLOCK) {
                 qemu_coroutine_yield();
             } else if (done == 0) {
                 return -1;