D7: editor multi-cursor support

Add secondary_cursors field to Editor with insert_char_multi,
delete_back_multi, delete_forward_multi methods. Right-to-left
processing ensures position shifts don't corrupt earlier insertions.

7 new tests: add/clear, all_positions, insert, delete_back,
delete_forward, unicode, duplicate-add.

local/recipes/tools/diffutils/source/lib/iconv_close.c

@@ -0,0 +1,46 @@
+/* Character set conversion.
+   Copyright (C) 2007, 2009-2017 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, 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 <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include <iconv.h>
+
+#include <stdint.h>
+#ifndef uintptr_t
+# define uintptr_t unsigned long
+#endif
+
+int
+rpl_iconv_close (iconv_t cd)
+#undef iconv_close
+{
+#if REPLACE_ICONV_UTF
+  switch ((uintptr_t) cd)
+    {
+    case (uintptr_t) _ICONV_UTF8_UTF16BE:
+    case (uintptr_t) _ICONV_UTF8_UTF16LE:
+    case (uintptr_t) _ICONV_UTF8_UTF32BE:
+    case (uintptr_t) _ICONV_UTF8_UTF32LE:
+    case (uintptr_t) _ICONV_UTF16BE_UTF8:
+    case (uintptr_t) _ICONV_UTF16LE_UTF8:
+    case (uintptr_t) _ICONV_UTF32BE_UTF8:
+    case (uintptr_t) _ICONV_UTF32LE_UTF8:
+      return 0;
+    }
+#endif
+  return iconv_close (cd);
+}