strtoumax: fix typo in previous commit.

[gnulib.git] / lib / sockets.c

diff --git a/lib/sockets.c b/lib/sockets.c
index cbec12d..ae96148 100644 (file)
--- a/lib/sockets.c
+++ b/lib/sockets.c
@@ -1,6 +1,6 @@
 /* sockets.c --- wrappers for Windows socket functions
 
-   Copyright (C) 2008-2009 Free Software Foundation, Inc.
+   Copyright (C) 2008-2013 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -22,22 +22,114 @@
 /* Specification.  */
 #include "sockets.h"
 
+#if WINDOWS_SOCKETS
+
 /* This includes winsock2.h on MinGW. */
-#include <sys/socket.h>
+# include <sys/socket.h>
+
+# include "fd-hook.h"
+# include "msvc-nothrow.h"
+
+/* Get set_winsock_errno, FD_TO_SOCKET etc. */
+# include "w32sock.h"
+
+static int
+close_fd_maybe_socket (const struct fd_hook *remaining_list,
+                       gl_close_fn primary,
+                       int fd)
+{
+  /* Note about multithread-safety: There is a race condition where, between
+     our calls to closesocket() and the primary close(), some other thread
+     could make system calls that allocate precisely the same HANDLE value
+     as sock; then the primary close() would call CloseHandle() on it.  */
+  SOCKET sock;
+  WSANETWORKEVENTS ev;
+
+  /* Test whether fd refers to a socket.  */
+  sock = FD_TO_SOCKET (fd);
+  ev.lNetworkEvents = 0xDEADBEEF;
+  WSAEnumNetworkEvents (sock, NULL, &ev);
+  if (ev.lNetworkEvents != 0xDEADBEEF)
+    {
+      /* fd refers to a socket.  */
+      /* FIXME: other applications, like squid, use an undocumented
+         _free_osfhnd free function.  But this is not enough: The 'osfile'
+         flags for fd also needs to be cleared, but it is hard to access it.
+         Instead, here we just close twice the file descriptor.  */
+      if (closesocket (sock))
+        {
+          set_winsock_errno ();
+          return -1;
+        }
+      else
+        {
+          /* This call frees the file descriptor and does a
+             CloseHandle ((HANDLE) _get_osfhandle (fd)), which fails.  */
+          _close (fd);
+          return 0;
+        }
+    }
+  else
+    /* Some other type of file descriptor.  */
+    return execute_close_hooks (remaining_list, primary, fd);
+}
+
+static int
+ioctl_fd_maybe_socket (const struct fd_hook *remaining_list,
+                       gl_ioctl_fn primary,
+                       int fd, int request, void *arg)
+{
+  SOCKET sock;
+  WSANETWORKEVENTS ev;
+
+  /* Test whether fd refers to a socket.  */
+  sock = FD_TO_SOCKET (fd);
+  ev.lNetworkEvents = 0xDEADBEEF;
+  WSAEnumNetworkEvents (sock, NULL, &ev);
+  if (ev.lNetworkEvents != 0xDEADBEEF)
+    {
+      /* fd refers to a socket.  */
+      if (ioctlsocket (sock, request, arg) < 0)
+        {
+          set_winsock_errno ();
+          return -1;
+        }
+      else
+        return 0;
+    }
+  else
+    /* Some other type of file descriptor.  */
+    return execute_ioctl_hooks (remaining_list, primary, fd, request, arg);
+}
+
+static struct fd_hook fd_sockets_hook;
+
+static int initialized_sockets_version /* = 0 */;
+
+#endif /* WINDOWS_SOCKETS */
 
 int
-gl_sockets_startup (int version)
+gl_sockets_startup (int version _GL_UNUSED)
 {
 #if WINDOWS_SOCKETS
-  WSADATA data;
-  int err;
+  if (version > initialized_sockets_version)
+    {
+      WSADATA data;
+      int err;
 
-  err = WSAStartup (version, &data);
-  if (err != 0)
-    return 1;
+      err = WSAStartup (version, &data);
+      if (err != 0)
+        return 1;
+
+      if (data.wVersion < version)
+        return 2;
+
+      if (initialized_sockets_version == 0)
+        register_fd_hook (close_fd_maybe_socket, ioctl_fd_maybe_socket,
+                          &fd_sockets_hook);
 
-  if (data.wVersion < version)
-    return 2;
+      initialized_sockets_version = version;
+    }
 #endif
 
   return 0;
@@ -49,6 +141,10 @@ gl_sockets_cleanup (void)
 #if WINDOWS_SOCKETS
   int err;
 
+  initialized_sockets_version = 0;
+
+  unregister_fd_hook (&fd_sockets_hook);
+
   err = WSACleanup ();
   if (err != 0)
     return 1;