Add mes and mescc-tools-extra

mescc-tools-extra contains two important tools:
- cp
- chmod

mes first builds itself from a mes 0.21 seed as used by guix, and then
builds a mes 0.22 and then mes 0.22 using that created mes 0.22.

It does /not/ use bootstrap.sh as we don't have a proper shell at this
point, it has been manually adapted for kaem.

sysa/mes-0.22/include/fcntl.h

@@ -0,0 +1,70 @@
+/* -*-comment-start: "//";comment-end:""-*-
+ * GNU Mes --- Maxwell Equations of Software
+ * Copyright © 2017 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ *
+ * This file is part of GNU Mes.
+ *
+ * GNU Mes 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.
+ *
+ * GNU Mes 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 GNU Mes.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __MES_FCNTL_H
+#define __MES_FCNTL_H 1
+
+#if SYSTEM_LIBC
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#undef __MES_FCNTL_H
+#include_next <fcntl.h>
+
+#else // ! SYSTEM_LIBC
+
+// *INDENT-OFF*
+#if __linux__
+#define O_RDONLY          0
+#define O_WRONLY          1
+#define O_RDWR            2
+#define O_CREAT        0x40
+#define O_EXCL         0x80
+#define O_TRUNC       0x200
+#define O_APPEND      0x400
+#define O_DIRECTORY 0x10000
+#elif __GNU__
+#define	O_RDONLY	  1
+#define	O_WRONLY	  2
+#define	O_RDWR		  3
+#define	O_CREAT	       0x10
+#define	O_APPEND      0x100
+#define	O_TRUNC	    0x10000
+#else
+#error platform not supported
+#endif
+// *INDENT-ON*
+
+#define FD_CLOEXEC 1
+
+#define F_DUPFD 0
+#define F_GETFD 1
+#define F_SETFD 2
+#define F_GETFL 3
+#define F_SETFL 4
+
+#define creat(file_name, mode) open (file_name, O_WRONLY | O_CREAT | O_TRUNC, mode)
+int dup (int old);
+int dup2 (int old, int new);
+int fcntl (int filedes, int command, ...);
+int open (char const *s, int flags, ...);
+
+#endif // ! SYSTEM_LIBC
+
+#endif // __MES_FCNTL_H