X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fpoll.c;h=780a6d67b52f131be89b161724b72b8b364f98f6;hb=88236bad53d1dd5e6b8a592a724736bbd9db7851;hp=aeb7a356fcbd05043f2c1523e5eaea725a577867;hpb=51c2a23373ee3583682e6faae3dc4f518bd03f04;p=gnulib.git

diff --git a/lib/poll.c b/lib/poll.c
index aeb7a356f..780a6d67b 100644
--- a/lib/poll.c
+++ b/lib/poll.c
@@ -1,7 +1,7 @@
 /* Emulation for poll(2)
    Contributed by Paolo Bonzini.
 
-   Copyright 2001-2003, 2006-2010 Free Software Foundation, Inc.
+   Copyright 2001-2003, 2006-2012 Free Software Foundation, Inc.
 
    This file is part of gnulib.
 
@@ -28,18 +28,22 @@
 #include <alloca.h>
 
 #include <sys/types.h>
-#include "poll.h"
+
+/* Specification.  */
+#include <poll.h>
+
 #include <errno.h>
 #include <limits.h>
 #include <assert.h>
 
 #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
-# define WIN32_NATIVE
+# define WINDOWS_NATIVE
 # include <winsock2.h>
 # include <windows.h>
 # include <io.h>
 # include <stdio.h>
 # include <conio.h>
+# include "msvc-nothrow.h"
 #else
 # include <sys/time.h>
 # include <sys/socket.h>
@@ -65,8 +69,10 @@
 # define MSG_PEEK 0
 #endif
 
-#ifdef WIN32_NATIVE
+#ifdef WINDOWS_NATIVE
 
+/* Optimized test whether a HANDLE refers to a console.
+   See <http://lists.gnu.org/archive/html/bug-gnulib/2009-08/msg00065.html>.  */
 #define IsConsoleHandle(h) (((long) (h) & 3) == 3)
 
 static BOOL
@@ -122,7 +128,7 @@ typedef DWORD (WINAPI *PNtQueryInformationFile)
    for the handle, eliminate them from *P_SOUGHT.  */
 
 static int
-win32_compute_revents (HANDLE h, int *p_sought)
+windows_compute_revents (HANDLE h, int *p_sought)
 {
   int i, ret, happened;
   INPUT_RECORD *irbuffer;
@@ -157,11 +163,12 @@ win32_compute_revents (HANDLE h, int *p_sought)
         {
           /* It was the write-end of the pipe.  Check if it is writable.
              If NtQueryInformationFile fails, optimistically assume the pipe is
-             writable.  This could happen on Win9x, where NtQueryInformationFile
-             is not available, or if we inherit a pipe that doesn't permit
-             FILE_READ_ATTRIBUTES access on the write end (I think this should
-             not happen since WinXP SP2; WINE seems fine too).  Otherwise,
-             ensure that enough space is available for atomic writes.  */
+             writable.  This could happen on Windows 9x, where
+             NtQueryInformationFile is not available, or if we inherit a pipe
+             that doesn't permit FILE_READ_ATTRIBUTES access on the write end
+             (I think this should not happen since Windows XP SP2; WINE seems
+             fine too).  Otherwise, ensure that enough space is available for
+             atomic writes.  */
           memset (&iosb, 0, sizeof (iosb));
           memset (&fpli, 0, sizeof (fpli));
 
@@ -220,7 +227,7 @@ win32_compute_revents (HANDLE h, int *p_sought)
 /* Convert fd_sets returned by select into revents values.  */
 
 static int
-win32_compute_revents_socket (SOCKET h, int sought, long lNetworkEvents)
+windows_compute_revents_socket (SOCKET h, int sought, long lNetworkEvents)
 {
   int happened = 0;
 
@@ -312,12 +319,9 @@ compute_revents (int fd, int sought, fd_set *rfds, fd_set *wfds, fd_set *efds)
 #endif /* !MinGW */
 
 int
-poll (pfd, nfd, timeout)
-     struct pollfd *pfd;
-     nfds_t nfd;
-     int timeout;
+poll (struct pollfd *pfd, nfds_t nfd, int timeout)
 {
-#ifndef WIN32_NATIVE
+#ifndef WINDOWS_NATIVE
   fd_set rfds, wfds, efds;
   struct timeval tv;
   struct timeval *ptv;
@@ -452,6 +456,7 @@ poll (pfd, nfd, timeout)
   if (!hEvent)
     hEvent = CreateEvent (NULL, FALSE, FALSE, NULL);
 
+restart:
   handle_array[0] = hEvent;
   nhandles = 1;
   FD_ZERO (&rfds);
@@ -499,13 +504,13 @@ poll (pfd, nfd, timeout)
         {
           /* Poll now.  If we get an event, do not poll again.  Also,
              screen buffer handles are waitable, and they'll block until
-             a character is available.  win32_compute_revents eliminates
+             a character is available.  windows_compute_revents eliminates
              bits for the "wrong" direction. */
-          pfd[i].revents = win32_compute_revents (h, &sought);
+          pfd[i].revents = windows_compute_revents (h, &sought);
           if (sought)
             handle_array[nhandles++] = h;
           if (pfd[i].revents)
-            wait_timeout = 0;
+            timeout = 0;
         }
     }
 
@@ -577,14 +582,14 @@ poll (pfd, nfd, timeout)
           if (FD_ISSET ((SOCKET) h, &xfds))
             ev.lNetworkEvents |= FD_OOB;
 
-          happened = win32_compute_revents_socket ((SOCKET) h, pfd[i].events,
-                                                   ev.lNetworkEvents);
+          happened = windows_compute_revents_socket ((SOCKET) h, pfd[i].events,
+                                                     ev.lNetworkEvents);
         }
       else
         {
           /* Not a socket.  */
           int sought = pfd[i].events;
-          happened = win32_compute_revents (h, &sought);
+          happened = windows_compute_revents (h, &sought);
           nhandles++;
         }
 
@@ -592,6 +597,12 @@ poll (pfd, nfd, timeout)
         rc++;
     }
 
+  if (!rc && timeout == INFTIM)
+    {
+      SwitchToThread();
+      goto restart;
+    }
+
   return rc;
 #endif
 }