Re: make-network-process(:nowait t) on MS-Windows

[Kyotaro HORIGUCHI <horiguti@meadowy.org>]

me> make-network-process<f> with parameter `:nowait t' returns nil
me> instead of process when evaluating the sample lisp code below on
me> MS-Windows. It seems to have worked once, but does not now.
me> 
me> The following patch make this work again.

The errors occurrs after make-network-process returned cannot be
caught with the previous patch. Because select() of Winsock
returns the failure of the connect with efds, not wfds.

Concerning only this issue, and using select(), the simplest way
to make this work as expected is to merge efds into wfds returned
by Winsock select().

-- 
Kyotaro HORIGUCHI

Index: w32proc.c
===================================================================
RCS file: /cvsroot/emacs/emacs/src/w32proc.c,v
retrieving revision 1.65
diff -u -2 -r1.65 w32proc.c
--- w32proc.c	7 Aug 2005 12:33:18 -0000	1.65
+++ w32proc.c	29 Nov 2005 04:13:45 -0000
@@ -1056,5 +1056,5 @@
   SELECT_TYPE orfds;
   DWORD timeout_ms, start_time;
-  int i, nh, nc, nr;
+  int i, nh, nc, nr, nw;
   DWORD active;
   child_process *cp, *cps[MAX_CHILDREN];
@@ -1072,5 +1072,5 @@
 
   /* Otherwise, we only handle rfds, so fail otherwise.  */
-  if (rfds == NULL || wfds != NULL || efds != NULL)
+  if ((rfds == NULL && wfds == NULL) || efds != NULL)
     {
       errno = EINVAL;
@@ -1081,4 +1081,5 @@
   FD_ZERO (rfds);
   nr = 0;
+  nw = 0;
 
   /* Always wait on interrupt_handle, to detect C-g (quit).  */
@@ -1185,4 +1186,25 @@
       }
 
+  if (wfds)
+    {
+      int i;
+      SELECT_TYPE efds = *wfds;
+      struct timeval tm = {0, 0};
+
+      nw = sys_select_socket (nfds, NULL, wfds, &efds, &tm);
+
+      /* merge retuend efds and wfds */
+      for (i = 0 ; i < nfds ; i++)
+	{
+	  if (FD_ISSET (i, &efds))
+	    FD_SET (i, wfds);
+	}
+
+      /* Assume this socket is waiting for connection of
+	 non-blocking socket. */
+      if (nw < 0)
+	return nw;
+    }
+
 count_children:
   /* Add handles of child processes.  */
@@ -1326,4 +1348,5 @@
 
   /* If no input has arrived and timeout hasn't expired, wait again.  */
+  nr += nw;
   if (nr == 0)
     {
Index: w32.c
===================================================================
RCS file: /cvsroot/emacs/emacs/src/w32.c,v
retrieving revision 1.97
diff -u -2 -r1.97 w32.c
--- w32.c	12 Sep 2005 10:27:02 -0000	1.97
+++ w32.c	29 Nov 2005 04:13:46 -0000
@@ -101,4 +101,9 @@
 #include "systime.h"
 
+typedef struct {
+  unsigned int fd_count;
+  SOCKET fd_array[FD_SETSIZE];
+} pfn_fd_set;
+
 typedef HRESULT (WINAPI * ShGetFolderPath_fn)
   (IN HWND, IN int, IN HANDLE, IN DWORD, OUT char *);
@@ -2696,4 +2701,5 @@
 int (PASCAL *pfn_bind) (SOCKET s, const struct sockaddr *addr, int namelen);
 int (PASCAL *pfn_connect) (SOCKET s, const struct sockaddr *addr, int namelen);
+int (PASCAL *pfn_select) (int nfds, pfn_fd_set *readfds, pfn_fd_set *writefds, pfn_fd_set *excepfds, const struct timeval FAR *timeout);
 int (PASCAL *pfn_ioctlsocket) (SOCKET s, long cmd, u_long *argp);
 int (PASCAL *pfn_recv) (SOCKET s, char * buf, int len, int flags);
@@ -2778,4 +2784,5 @@
       LOAD_PROC( bind );
       LOAD_PROC( connect );
+      LOAD_PROC( select );
       LOAD_PROC( ioctlsocket );
       LOAD_PROC( recv );
@@ -2852,4 +2859,5 @@
     case WSAENAMETOOLONG: 	h_errno = ENAMETOOLONG; break;
     case WSAENOTEMPTY:		h_errno = ENOTEMPTY; break;
+    case WSAEWOULDBLOCK:	h_errno = EINPROGRESS; break;
     }
   errno = h_errno;
@@ -3136,4 +3144,69 @@
   h_errno = ENOTSOCK;
   return SOCKET_ERROR;
+}
+
+int
+sys_select_socket (int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout)
+{
+  int i, j, k, rc, cfds;
+  pfn_fd_set *fds[3];
+  fd_set *efds[3];
+
+  if (winsock_lib == NULL)
+    {
+      h_errno = ENOTSOCK;
+      return SOCKET_ERROR;
+    }
+
+  check_errno ();
+
+  cfds = 0;
+  efds[0] = readfds;
+  efds[1] = writefds;
+  efds[2] = exceptfds;
+
+  for (i = 0 ; i < 3 ; i++)
+    {
+      fds[i] = NULL;
+      if (efds[i])
+	{
+	  fds[i] = (pfn_fd_set*)alloca (sizeof (pfn_fd_set));
+	  fds[i]->fd_count = 0;
+	  for (j = 0 ; j < nfds ; j++)
+	    if (FD_ISSET (j, efds[i]))
+	      {
+		if (! (fd_info[j].flags & FILE_SOCKET))
+		  {
+		    h_errno = ENOTSOCK;
+		    return SOCKET_ERROR;
+		  }
+	      
+		fds[i]->fd_array[fds[i]->fd_count++] = SOCK_HANDLE (j);
+		cfds++;
+	      }
+	  FD_ZERO (efds[i]);
+	}
+    }
+
+  if (cfds == 0)
+    return 0;
+
+  rc = pfn_select (nfds, fds[0], fds[1], fds[2], timeout);
+
+  if (rc > 0)
+    for (i = 0 ; i < 3 ; i++)
+      if (fds[i])
+	for (j = 0 ; j < fds[i]->fd_count ; j++)
+	  {
+	    for (k = 0 ;
+		 k < nfds && fds[i]->fd_array [j] != SOCK_HANDLE (k) ;
+		 k++);
+	    if (k < nfds)
+	      FD_SET (k, efds[i]);
+	  }
+
+  if (rc == SOCKET_ERROR)
+    set_errno ();
+  return rc;
 }