pselect: reject invalid file descriptors

[gnulib.git] / lib / pselect.c

diff --git a/lib/pselect.c b/lib/pselect.c
index 4e7a7ed..b544c7c 100644 (file)
--- a/lib/pselect.c
+++ b/lib/pselect.c
@@ -33,6 +33,8 @@
    pointer parameter stands for no descriptors, an infinite timeout,
    or an unaffected signal mask.  */
 
+#if !HAVE_PSELECT
+
 int
 pselect (int nfds, fd_set *restrict rfds,
          fd_set *restrict wfds, fd_set *restrict xfds,
@@ -74,3 +76,35 @@ pselect (int nfds, fd_set *restrict rfds,
 
   return select_result;
 }
+
+#else /* HAVE_PSELECT */
+# include <unistd.h>
+# undef pselect
+
+int
+rpl_pselect (int nfds, fd_set *restrict rfds,
+            fd_set *restrict wfds, fd_set *restrict xfds,
+             struct timespec const *restrict timeout,
+            sigset_t const *restrict sigmask)
+{
+  int i;
+
+  /* FreeBSD 8.2 has a bug: it does not always detect invalid fds.  */
+  if (nfds < 0 || nfds > FD_SETSIZE)
+    {
+      errno = EINVAL;
+      return -1;
+    }
+  for (i = 0; i < nfds; i++)
+    {
+      if (((rfds && FD_ISSET (i, rfds))
+           || (wfds && FD_ISSET (i, wfds))
+           || (xfds && FD_ISSET (i, xfds)))
+          && dup2 (i, i) != i)
+        return -1;
+    }
+
+  return pselect (nfds, rfds, wfds, xfds, timeout, sigmask);
+}
+
+#endif