#10053: Don't close FDs when FileIO.__init__ fails

Loosely based on the work by Hirokazu Yamamoto.
diff --git a/Modules/_io/fileio.c b/Modules/_io/fileio.c
index d1941df..e23fc6e 100644
--- a/Modules/_io/fileio.c
+++ b/Modules/_io/fileio.c
@@ -195,6 +195,7 @@
     int flags = 0;
     int fd = -1;
     int closefd = 1;
+    int fd_is_own = 0;
 
     assert(PyFileIO_Check(oself));
     if (self->fd >= 0) {
@@ -345,6 +346,7 @@
 #endif
             self->fd = open(name, flags, 0666);
         Py_END_ALLOW_THREADS
+        fd_is_own = 1;
         if (self->fd < 0) {
 #ifdef MS_WINDOWS
             if (widename != NULL)
@@ -366,19 +368,17 @@
            end of file (otherwise, it might be done only on the
            first write()). */
         PyObject *pos = portable_lseek(self->fd, NULL, 2);
-        if (pos == NULL) {
-            if (closefd) {
-                close(self->fd);
-                self->fd = -1;
-            }
+        if (pos == NULL)
             goto error;
-        }
         Py_DECREF(pos);
     }
 
     goto done;
 
  error:
+    if (!fd_is_own)
+        self->fd = -1;
+
     ret = -1;
 
  done: