[PATCH] Re: Resend ([Q] apr_poll_revents_get() before apr_accept() on Windows)

[Saxon <sa...@saxon.cx>]

Thanks INOUE - I was going to repost it myself in a few days :)

Here's the patch again in case the old one is missing / too hard to find:

========================================================================
--- apr/network_io/win32/poll.c.old Mon Mar 25 16:37:46 2002
+++ apr/network_io/win32/poll.c Mon Mar 25 16:38:53 2002
@@ -156,6 +156,9 @@
     DWORD dummy;
     DWORD flags = MSG_PEEK;

+    BOOL optval;
+    int optlen;
+
     /* We just want to PEEK at the data, so I am setting up a dummy WSABUF
      * variable here.
      */
@@ -164,27 +167,45 @@

     if (FD_ISSET(sock->sock, aprset->read)) {
         revents |= APR_POLLIN;
-        if (WSARecv(sock->sock, &data, 1, &dummy, &flags, NULL,
-                    NULL) == SOCKET_ERROR) {
-            /* This is only legit since we don't return the error */
-            dummy = WSAGetLastError();
-            switch (dummy) {
-                case WSAECONNRESET:
-                case WSAECONNABORTED:
-                case WSAESHUTDOWN:
-                case WSAENETRESET: {
-                    revents ^= APR_POLLIN;
-                    revents |= APR_POLLHUP;
-                    break;
-                }
-                case WSAENOTSOCK: {
-                    revents ^= APR_POLLIN;
-                    revents |= APR_POLLNVAL;
-                }
-                default: {
-                    revents ^= APR_POLLIN;
-                    revents |= APR_POLLERR;
+
+        /* Check if the socket is listening for a connection (SO_ACCEPTCONN
+         * is true) - if it is we just leave APR_POLLIN in revents and
+         * don't attempt the WSARecv, since it would return WSAENOTCONN.
+         */
+        optlen = sizeof(optval);
+        getsockopt(sock->sock, SOL_SOCKET, SO_ACCEPTCONN, (char *)&optval,
+            &optlen);
+        if (!optval) {
+            /* The socket is not listening */
+            if (WSARecv(sock->sock, &data, 1, &dummy, &flags, NULL,
+                        NULL) == SOCKET_ERROR) {
+                /* This is only legit since we don't return the error */
+                dummy = WSAGetLastError();
+                switch (dummy) {
+                    case WSAECONNRESET:
+                    case WSAECONNABORTED:
+                    case WSAESHUTDOWN:
+                    case WSAENETRESET: {
+                        revents ^= APR_POLLIN;
+                        revents |= APR_POLLHUP;
+                        break;
+                    }
+                    case WSAENOTSOCK: {
+                        revents ^= APR_POLLIN;
+                        revents |= APR_POLLNVAL;
+                    }
+                    default: {
+                        revents ^= APR_POLLIN;
+                        revents |= APR_POLLERR;
+                    }
                 }
+            }
+            else if ((dummy == 0) && (sock->type == SOCK_STREAM)) {
+                /* Zero bytes received (dummy is the number of bytes)
+                 * from a stream socket indicates graceful shutdown.
+                 */
+                revents ^= APR_POLLIN;
+                revents |= APR_POLLHUP;
             }
         }
     }

========================================================================

bye,
Saxon Druce (saxon@blocksoftware.com)

----- Original Message -----
From: "INOUE Seiichiro" <in...@ariel-networks.com>
To: <de...@apr.apache.org>
Sent: Monday, April 22, 2002 11:31 PM
Subject: Resend ([Q] apr_poll_revents_get() before apr_accept() on Windows)


> Hi,
>
> I formerly sent a question about the issue on Subject.
> For my post, Mr. Saxon showed his patch, but the patch hasn't been
committed yet.
>
> What is goint on?
>
> Thanks.
>
>
> > ----- My Original Message -----
> > From: "INOUE Seiichiro" <in...@ariel-networks.com>
> > To: <de...@apr.apache.org>
> > Sent: Monday, March 25, 2002 12:32 AM
> > Subject: [Q] apr_poll_revents_get() before apr_accept() on Windows
> > > Hi,
> > >
> > > I have a question about apr_poll_revents_get() behavior on Windows.
> > > I want to check whether the socket is apr_accept()'able.
> > > On Unix, I can check the socket becomes readable by apr_poll().
> > > On Windows, when I do the same thing, apr_poll_revents_get() returns
> > APR_POLLERR.
> > >
> > > In apr_poll_revents_get(), WSARecv() causes WSAENOTCONN,
> > > if the socket hasn't been apr_accept()'ed yet.
> > > (Windows2000 case. I don't know other Windows.)
> > >
> > > I attach a sample program for an easy reproduction.
> > >
> > > My question is,
> > > What is a proper solution?
> > > libapr should take care of it, or applications should?
> > >
> > > Thanks in advance.
> > >
> > > - INOUE Seiichiro <in...@ariel-networks.com>
> > >   http://www.ariel-networks.com