[PATCH v6 resend 05/10] server: Defer clearing events until async is completed in send_socket handler.

[Jinoh Kang]

This allows the initial I/O to be performed after the send_socket
handler is called.

Signed-off-by: Jinoh Kang 
---

Notes:
    v4 -> v5: new patch
    v5 -> v6:
    - fix erroneous subject (s/either pending or completed/completed/)

server/sock.c | 56 ++++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 42 insertions(+), 14 deletions(-)

diff --git a/server/sock.c b/server/sock.c
index 91f98556552..0441ce2bbfa 100644
--- a/server/sock.c
+++ b/server/sock.c
@@ -153,6 +153,12 @@ struct connect_req
     unsigned int addr_len, send_len, send_cursor;
 };

+struct send_req
+{
+    struct iosb *iosb;
+    struct sock *sock;
+};
+
 enum connection_state
 {
     SOCK_LISTENING,
@@ -3454,6 +3460,26 @@ DECL_HANDLER(recv_socket)
     release_object( sock );
 }

+static void send_socket_completion_callback( void *private )
+{
+    struct send_req *send_req = private;
+    struct iosb *iosb = send_req->iosb;
+    struct sock *sock = send_req->sock;
+
+    if (iosb->status != STATUS_SUCCESS)
+    {
+        /* send() calls only clear and reselect events if unsuccessful. */
+        sock->pending_events &= ~AFD_POLL_WRITE;
+        sock->reported_events &= ~AFD_POLL_WRITE;
+    }
+
+    sock_reselect( sock );
+
+    release_object( iosb );
+    release_object( sock );
+    free( send_req );
+}
+
 DECL_HANDLER(send_socket)
 {
     struct sock *sock = (struct sock *)get_handle_obj( current->process, req->async.handle, 0, &sock_ops );
@@ -3476,13 +3502,6 @@ DECL_HANDLER(send_socket)
         sock->bound = 1;
     }

-    if (status != STATUS_SUCCESS)
-    {
-        /* send() calls only clear and reselect events if unsuccessful. */
-        sock->pending_events &= ~AFD_POLL_WRITE;
-        sock->reported_events &= ~AFD_POLL_WRITE;
-    }
-
     /* If we had a short write and the socket is nonblocking (and the client is
      * not trying to force the operation to be asynchronous), return success.
      * Windows actually refuses to send any data in this case, and returns
@@ -3510,22 +3529,31 @@ DECL_HANDLER(send_socket)

if ((async = create_request_async( fd, get_fd_comp_flags( fd ), &req->async )))
     {
-        if (status == STATUS_SUCCESS)
+        struct send_req *send_req;
+        struct iosb *iosb = async_get_iosb( async );
+
+        if ((send_req = mem_alloc( sizeof(*send_req) )))
         {
-            struct iosb *iosb = async_get_iosb( async );
-            iosb->result = req->total;
-            release_object( iosb );
+            send_req->iosb = (struct iosb *)grab_object( iosb );
+            send_req->sock = (struct sock *)grab_object( sock );
+            async_set_completion_callback( async, send_socket_completion_callback, send_req );
         }
+        else if (status == STATUS_PENDING || status == STATUS_DEVICE_NOT_READY)
+            status = STATUS_NO_MEMORY;
+
+        if (status == STATUS_SUCCESS) iosb->result = req->total;
+        release_object( iosb );
+
         set_error( status );

if (timeout)
             async_set_timeout( async, timeout, STATUS_IO_TIMEOUT );

if (status == STATUS_PENDING)
+        {
             queue_async( &sock->write_q, async );
-
-        /* always reselect; we changed reported_events above */
-        sock_reselect( sock );
+            sock_reselect( sock );
+        }

reply->wait = async_handoff( async, NULL, 0 );
         reply->options = get_fd_options( fd );