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/lib/tests/scaffold/61-array.c

@@ -0,0 +1,150 @@
+/* -*-comment-start: "//";comment-end:""-*-
+ * GNU Mes --- Maxwell Equations of Software
+ * Copyright © 2017,2018 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/>.
+ */
+
+#include <mes/lib.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+char *env[] = { "foo", "bar", "baz", 0 };
+
+#if 0                           //!SYSTEM_LIBC
+#define getenv xgetenv
+
+char *
+getenv (char const *s)
+{
+  eputs ("getenv\n");
+  char **p = environ;
+  int length = strlen (s);
+  eputs ("getenv length=");
+  eputs (itoa (length));
+  eputs ("\n");
+  while (*p)
+    {
+      eputs ("*p=");
+      eputs (*p);
+      eputs ("\n");;
+      eputs (" p=");
+      eputs (itoa ((long) p));
+      eputs ("\n");
+      if (!strncmp (s, *p, length) && *(*p + length) == '=')
+        return (*p + length + 1);
+      p++;
+    }
+  return 0;
+}
+#endif
+
+int
+test (char **e)
+{
+  int i = 0;
+
+  oputs ("\n");
+  oputs ("a[i] = i-1\n");
+  int a[3];
+  for (int i = 0; i < 3; i++)
+    a[i] = i - 1;
+  for (int i = 0; i < 3; i++)
+    if (a[i] != i - 1)
+      return 1;
+
+  oputs ("env [");
+  oputs (itoa ((long) env));
+  oputs ("]\n");
+
+  oputs ("e [");
+  oputs (itoa ((int) e));
+  oputs ("]\n");
+
+  oputs ("env [0] == \"foo\"\n");
+  if (strcmp (env[0], "foo"))
+    return 2;
+
+  oputs ("env [1] == \"bar\"\n");
+  if (strcmp (env[1], "bar"))
+    return 3;
+
+  oputs ("t: **p in *env[]\n");
+
+  char **pp = env;
+  while (*pp)
+    {
+      oputs ("pp [");
+      oputs (itoa ((int) pp));
+      oputs ("]: ");
+      if (*pp)
+        oputs (*pp);
+      oputs ("\n");
+      pp++;
+      i++;
+    }
+  if (i != 3)
+    return i;
+
+  pp = env;
+  oputs ("t: *pp++ == \"foo\"\n");
+  if (strcmp (*pp++, "foo"))
+    return 4;
+
+  oputs ("t: *pp++ == \"bar\"\n");
+  if (strcmp (*pp++, "bar"))
+    return 5;
+
+  char *buf = "hello";
+  oputs ("t: buf[0]\n");
+  if (buf[0] != 'h')
+    return 6;
+
+  oputs ("t: buf + 1\n");
+  if (*(buf + 1) != 'e')
+    return 7;
+
+  char **p = &buf;
+  oputs ("t: **p\n");
+  if (**p != 'h')
+    return 8;
+
+  oputs ("t: *(p + 1)\n");
+  if (*(*p + 1) != 'e')
+    return 9;
+
+  oputs ("t: getenv ()\n");
+  if (!getenv ("PATH"))
+    return 10;
+
+  oputs ("t: setenv ()\n");
+  if (setenv ("61-array", "yes", 1))
+    return 11;
+
+  oputs ("t: getenv2 ()\n");
+  if (strcmp (getenv ("61-array"), "yes"))
+    return 12;
+
+  return 0;
+}
+
+int
+main (int argc, char *argv[])
+{
+  return test (env);
+}