* dtable.cc (dtable::vfork_parent_restore): Add debugging statement.

* exceptions.cc (try_to_debug): Spin only as long as we don't have a debugger
attached.
* fhandler.h (fhandler_base::set_nohandle): New method.
(fhandler_base::get_nohandle): New method.
* fhandler.cc (fhandler_base::dup): Avoid duplicating handle if there is no
handle.
* fhandler_disk_file.cc (fhandler_disk_file::opendir): Set nohandle flag on
dummy fd.
* Makefile.in: Make intermediate library for eventual inclusion in libcygwin.a
* fhandler.h (fhandler_pipe::fhandler_pipe): Remove default argument setting
since it is no longer used.
* miscfuncs.cc (check_null_str): New function.
(+check_null_str_errno): Ditto.
* net.cc: Add defensive buffer checking throughout.
(cygwin_sendto): Protect against invalid fd.
(cygwin_recvfrom): Ditto.
(cygwin_getpeername): Ditto.
(cygwin_recv): Ditto.
(cygwin_send): Ditto.
* winsup.h: Declare a new function.
* select.cc (set_bits): Fix conditional for setting fd in exceptfds.
* dtable.cc (dtable::build_fhandler): Create fhandler_pipe using correct device
type.
* path.cc (get_devn): Set correct pipe device type from device name.

winsup/cygwin/miscfuncs.cc

@@ -115,6 +115,15 @@ strcasestr (const char *searchee, const char *lookfor)
   return NULL;
 }
 
+int __stdcall
+check_null_str (const char *name)
+{
+  if (name && !IsBadStringPtr (name, MAX_PATH))
+    return 0;
+
+  return EFAULT;
+}
+
 int __stdcall
 check_null_empty_str (const char *name)
 {
@@ -133,6 +142,15 @@ check_null_empty_str_errno (const char *name)
   return __err;
 }
 
+int __stdcall
+check_null_str_errno (const char *name)
+{
+  int __err;
+  if ((__err = check_null_str (name)))
+    set_errno (__err);
+  return __err;
+}
+
 int __stdcall
 __check_null_invalid_struct (const void *s, unsigned sz)
 {