* poll.cc (poll): Return count of fds with events instead of total

	event count.

	* poll.cc (poll): Use POSIX type nfds_t for second parameter.
	* include/sys/poll.h: Declare nfds_t.  Use as type for second parameter
	in poll(2) declaration.

3 files changed, 216 insertions, 0 deletions

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 81ea10f82fb..06136ffefa9 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,9 @@
+2007-12-13  Craig MacGregor  <cmacgreg@gmail.com>
+	    Corinna Vinschen  <corinna@vinschen.de>
+
+	* poll.cc (poll): Return count of fds with events instead of total
+	event count.
+
 2007-12-11  Corinna Vinschen  <corinna@vinschen.de>
 
 	* fhandler_disk_file.cc (fhandler_base::fstat_helper): Fix R/O bit
@@ -632,6 +638,12 @@
 	* fhandler_disk_file.cc (fhandler_disk_file::lock): Handle
 	ERROR_NOT_LOCKED returned from UnlockFileEx.
 
+2006-07-31  Corinna Vinschen  <corinna@vinschen.de>
+
+	* poll.cc (poll): Use POSIX type nfds_t for second parameter.
+	* include/sys/poll.h: Declare nfds_t.  Use as type for second parameter
+	in poll(2) declaration.
+
 2006-07-23  Christopher Faylor  <cgf@timesys.com>
 
 	* include/cygwin/version.h: Bump DLL minor version number to 22.
diff --git a/winsup/cygwin/include/sys/poll.h b/winsup/cygwin/include/sys/poll.h
new file mode 100644
index 00000000000..7fd1c6eb053
--- /dev/null
+++ b/winsup/cygwin/include/sys/poll.h
@@ -0,0 +1,45 @@
+/* sys/poll.h
+
+   Copyright 2000, 2001, 2006 Red Hat, Inc.
+
+   This file is part of Cygwin.
+
+   This software is a copyrighted work licensed under the terms of the
+   Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
+   details. */
+
+#ifndef _SYS_POLL_H
+#define _SYS_POLL_H
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+#define POLLIN  1       /* Set if data to read. */
+#define POLLPRI 2       /* Set if urgent data to read. */
+#define POLLOUT 4       /* Set if writing data wouldn't block. */
+#define POLLERR   8     /* An error occured. */
+#define POLLHUP  16     /* Shutdown or close happened. */
+#define POLLNVAL 32     /* Invalid file descriptor. */
+
+#define NPOLLFILE 64    /* Number of canonical fd's in one call to poll(). */
+
+/* The following values are defined by XPG4. */
+#define POLLRDNORM POLLIN
+#define POLLRDBAND POLLPRI
+#define POLLWRNORM POLLOUT
+#define POLLWRBAND POLLOUT
+
+struct pollfd {
+  int fd;
+  short events;
+  short revents;
+};
+
+typedef unsigned int nfds_t;
+
+extern int poll __P ((struct pollfd *fds, nfds_t nfds, int timeout));
+
+__END_DECLS
+
+#endif /* _SYS_POLL_H */
diff --git a/winsup/cygwin/poll.cc b/winsup/cygwin/poll.cc
new file mode 100644
index 00000000000..a9b4a233a68
--- /dev/null
+++ b/winsup/cygwin/poll.cc
@@ -0,0 +1,159 @@
+/* poll.cc. Implements poll(2) via usage of select(2) call.
+
+   Copyright 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 Red Hat, Inc.
+
+   This file is part of Cygwin.
+
+   This software is a copyrighted work licensed under the terms of the
+   Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
+   details. */
+
+#define  __INSIDE_CYGWIN_NET__
+
+#define FD_SETSIZE 16384		// lots of fds
+#include "winsup.h"
+#include <sys/time.h>
+#include <sys/poll.h>
+#include <sys/socket.h>
+#include <stdlib.h>
+#define USE_SYS_TYPES_FD_SET
+#include <winsock2.h>
+#include "cygerrno.h"
+#include "security.h"
+#include "path.h"
+#include "fhandler.h"
+#include "dtable.h"
+#include "cygheap.h"
+#include "sigproc.h"
+
+extern "C" int
+poll (struct pollfd *fds, nfds_t nfds, int timeout)
+{
+  int max_fd = 0;
+  fd_set *read_fds, *write_fds, *except_fds;
+  struct timeval tv = { timeout / 1000, (timeout % 1000) * 1000 };
+
+  for (unsigned int i = 0; i < nfds; ++i)
+    if (fds[i].fd > max_fd)
+      max_fd = fds[i].fd;
+
+  size_t fds_size = howmany (max_fd + 1, NFDBITS) * sizeof (fd_mask);
+
+  read_fds = (fd_set *) alloca (fds_size);
+  write_fds = (fd_set *) alloca (fds_size);
+  except_fds = (fd_set *) alloca (fds_size);
+
+  if (!read_fds || !write_fds || !except_fds)
+    {
+      set_errno (EINVAL);	/* According to SUSv3. */
+      return -1;
+    }
+
+  memset (read_fds, 0, fds_size);
+  memset (write_fds, 0, fds_size);
+  memset (except_fds, 0, fds_size);
+
+  int invalid_fds = 0;
+  for (unsigned int i = 0; i < nfds; ++i)
+    {
+      fds[i].revents = 0;
+      if (!cygheap->fdtab.not_open (fds[i].fd))
+	{
+	  if (fds[i].events & POLLIN)
+	    FD_SET(fds[i].fd, read_fds);
+	  if (fds[i].events & POLLOUT)
+	    FD_SET(fds[i].fd, write_fds);
+	  /* On sockets, except_fds is needed to catch failed connects. */
+	  if ((fds[i].events & POLLPRI)
+	      || cygheap->fdtab[fds[i].fd]->is_socket ())
+	    FD_SET(fds[i].fd, except_fds);
+	}
+      else if (fds[i].fd >= 0)
+	{
+	  ++invalid_fds;
+	  fds[i].revents = POLLNVAL;
+	}
+    }
+
+  if (invalid_fds)
+    return invalid_fds;
+
+  int ret = cygwin_select (max_fd + 1, read_fds, write_fds, except_fds,
+			   timeout < 0 ? NULL : &tv);
+  if (ret <= 0)
+    return ret;
+
+  /* Set revents fields and count fds with non-zero revents fields for
+     return value. */
+  ret = 0;
+  for (unsigned int i = 0; i < nfds; ++i)
+    {
+      if (fds[i].fd >= 0)
+	{
+	  if (cygheap->fdtab.not_open (fds[i].fd))
+	    fds[i].revents = POLLHUP;
+	  else
+	    {
+	      fhandler_socket *sock;
+
+	      if (FD_ISSET(fds[i].fd, read_fds))
+		{
+		  char peek[1];
+		  sock = cygheap->fdtab[fds[i].fd]->is_socket ();
+		  if (!sock)
+		    fds[i].revents |= POLLIN;
+		  else
+		    {
+		      /* The following action can change errno.  We have to
+			 reset it to it's old value. */
+		      int old_errno = get_errno ();
+		      switch (sock->recvfrom (peek, sizeof (peek), MSG_PEEK,
+					      NULL, NULL))
+			{
+			  case -1: /* Something weird happened */
+			    /* When select returns that data is available,
+			       that could mean that the socket is in
+			       listen mode and a client tries to connect.
+			       Unfortunately, recvfrom() doesn't make much
+			       sense then.  It returns WSAENOTCONN in that
+			       case.  Since that's not actually an error,
+			       we must not set POLLERR but POLLIN. */
+			    if (WSAGetLastError () != WSAENOTCONN)
+			      fds[i].revents |= POLLERR;
+			    else
+			      fds[i].revents |= POLLIN;
+			    break;
+			  case 0:  /* Closed on the read side... */
+			    /* ...or shutdown(SHUT_WR) on the write side.
+			       We set revents to POLLHUP until 1.5.18, but
+			       this is semantically borderline. */
+			    fds[i].revents |= POLLIN;
+			    break;
+			  default:
+			    fds[i].revents |= POLLIN;
+			    break;
+			}
+		      set_errno (old_errno);
+		    }
+		}
+	      /* Handle failed connect. */
+	      if (FD_ISSET(fds[i].fd, write_fds)
+		  && FD_ISSET(fds[i].fd, except_fds)
+		  && (sock = cygheap->fdtab[fds[i].fd]->is_socket ())
+		  && sock->connect_state () == connect_failed)
+		fds[i].revents |= (POLLIN | POLLERR);
+	      else
+		{
+		  if (FD_ISSET(fds[i].fd, write_fds))
+		    fds[i].revents |= POLLOUT;
+		  if (FD_ISSET(fds[i].fd, except_fds))
+		    fds[i].revents |= POLLPRI;
+		}
+	    }
+	  if (fds[i].revents)
+	    ++ret;
+	}
+    }
+
+  return ret;
+}