1 files changed, 85 insertions, 0 deletions
diff --git a/lib/ftello.c b/lib/ftello.c
new file mode 100644
index 0000000..495c254
--- /dev/null
+++ b/lib/ftello.c
@@ -0,0 +1,85 @@
+/* An ftello() function that works around platform bugs.
+   Copyright (C) 2007, 2009-2018 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
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include <stdio.h>
+
+/* Get lseek.  */
+#include <unistd.h>
+
+#include "stdio-impl.h"
+
+off_t
+ftello (FILE *fp)
+#undef ftello
+#if !HAVE_FTELLO
+# undef ftell
+# define ftello ftell
+#endif
+#if _GL_WINDOWS_64_BIT_OFF_T
+# undef ftello
+# if HAVE__FTELLI64 /* msvc, mingw64 */
+#  define ftello _ftelli64
+# else /* mingw */
+#  define ftello ftello64
+# endif
+#endif
+{
+#if LSEEK_PIPE_BROKEN
+  /* mingw gives bogus answers rather than failure on non-seekable files.  */
+  if (lseek (fileno (fp), 0, SEEK_CUR) == -1)
+    return -1;
+#endif
+
+#if FTELLO_BROKEN_AFTER_SWITCHING_FROM_READ_TO_WRITE /* Solaris */
+  /* The Solaris stdio leaves the _IOREAD flag set after reading from a file
+     reaches EOF and the program then starts writing to the file.  ftello
+     gets confused by this.  */
+  if (fp_->_flag & _IOWRT)
+    {
+      off_t pos;
+
+      /* Call ftello nevertheless, for the side effects that it does on fp.  */
+      ftello (fp);
+
+      /* Compute the file position ourselves.  */
+      pos = lseek (fileno (fp), (off_t) 0, SEEK_CUR);
+      if (pos >= 0)
+        {
+          if ((fp_->_flag & _IONBF) == 0 && fp_->_base != NULL)
+            pos += fp_->_ptr - fp_->_base;
+        }
+      return pos;
+    }
+#endif
+
+#if defined __SL64 && defined __SCLE /* Cygwin */
+  if ((fp->_flags & __SL64) == 0)
+    {
+      /* Cygwin 1.5.0 through 1.5.24 failed to open stdin in 64-bit
+         mode; but has an ftello that requires 64-bit mode.  */
+      FILE *tmp = fopen ("/dev/null", "r");
+      if (!tmp)
+        return -1;
+      fp->_flags |= __SL64;
+      fp->_seek64 = tmp->_seek64;
+      fclose (tmp);
+    }
+#endif
+  return ftello (fp);
+}