config/git: import suckless sbase

i currently use the output of sha512sum in several
places of xbmk, which is a bit unreliable in case
output changes.

other cases where i use util outputs in variables
are probably reliable, because i'm using mostly
posix utilities in those.

to mitigate this, i now import suckless sbase, which
has a reasonable sha512sum implementation.

*every* binary it builds is being placed in build.list,
because i'll probably start using more of them.

for example, i may start modifying the "date"
implementation, adding the GNU-specific options that
i need as mentioned on init.sh

i'm importing it in util/ because the sha512sum
util is needed for verifying project sources, so
if sbase itself is a "project source", that means
we can into a chicken and egg bootstrapping problem.

this is sbase at revision:
055cc1ae1b3a13c3d8f25af0a4a3316590efcd48

Signed-off-by: Leah Rowe <leah@libreboot.org>

util/sbase/mknod.c

@@ -0,0 +1,72 @@
+/* See LICENSE file for copyright and license details. */
+#include <sys/stat.h>
+#include <sys/types.h>
+#ifndef makedev
+#include <sys/sysmacros.h>
+#endif
+
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "util.h"
+
+static void
+usage(void)
+{
+	eprintf("usage: %s [-m mode] name b|c|u major minor\n"
+	        "       %s [-m mode] name p\n",
+	        argv0, argv0);
+}
+
+int
+main(int argc, char *argv[])
+{
+	mode_t mode = 0666;
+	dev_t dev;
+
+	ARGBEGIN {
+	case 'm':
+		mode = parsemode(EARGF(usage()), mode, umask(0));
+		break;
+	default:
+		usage();
+	} ARGEND;
+
+	if (argc < 2)
+		usage();
+
+	if (strlen(argv[1]) != 1)
+		goto invalid;
+	switch (argv[1][0]) {
+	case 'b':
+		mode |= S_IFBLK;
+		break;
+	case 'u':
+	case 'c':
+		mode |= S_IFCHR;
+		break;
+	case 'p':
+		mode |= S_IFIFO;
+		break;
+	default:
+	invalid:
+		eprintf("invalid type '%s'\n", argv[1]);
+	}
+
+	if (S_ISFIFO(mode)) {
+		if (argc != 2)
+			usage();
+		dev = 0;
+	} else {
+		if (argc != 4)
+			usage();
+		dev = makedev(estrtonum(argv[2], 0, LLONG_MAX), estrtonum(argv[3], 0, LLONG_MAX));
+	}
+
+	if (mknod(argv[0], mode, dev) == -1)
+		eprintf("mknod %s:", argv[0]);
+	return 0;
+}