1 files changed, 37 insertions, 0 deletions

diff --git a/gl/ftell.c b/gl/ftell.c
new file mode 100644
index 00000000..ce2bd542
--- /dev/null
+++ b/gl/ftell.c
@@ -0,0 +1,37 @@
+/* An ftell() function that works around platform bugs.
+   Copyright (C) 2007-2023 Free Software Foundation, Inc.
+
+   This file is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Lesser General Public License as
+   published by the Free Software Foundation; either version 2.1 of the
+   License, or (at your option) any later version.
+
+   This file is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include <stdio.h>
+
+#include <errno.h>
+#include <limits.h>
+
+long
+ftell (FILE *fp)
+{
+  /* Use the replacement ftello function with all its workarounds.  */
+  off_t offset = ftello (fp);
+  if (LONG_MIN <= offset && offset <= LONG_MAX)
+    return /* (long) */ offset;
+  else
+    {
+      errno = EOVERFLOW;
+      return -1;
+    }
+}