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/chmod.c

@@ -0,0 +1,77 @@
+/* See LICENSE file for copyright and license details. */
+#include <fcntl.h>
+#include <sys/stat.h>
+
+#include "fs.h"
+#include "util.h"
+
+static char  *modestr = "";
+static mode_t mask    = 0;
+static int    ret     = 0;
+
+static void
+chmodr(int dirfd, const char *name, struct stat *st, void *data, struct recursor *r)
+{
+	mode_t m;
+
+	m = parsemode(modestr, st->st_mode, mask);
+	if (!S_ISLNK(st->st_mode) && fchmodat(dirfd, name, m, 0) < 0) {
+		weprintf("chmod %s:", r->path);
+		ret = 1;
+	} else if (S_ISDIR(st->st_mode)) {
+		recurse(dirfd, name, NULL, r);
+	}
+}
+
+static void
+usage(void)
+{
+	eprintf("usage: %s [-R] mode file ...\n", argv0);
+}
+
+int
+main(int argc, char *argv[])
+{
+	struct recursor r = { .fn = chmodr, .maxdepth = 1, .follow = 'H', .flags = DIRFIRST };
+	size_t i;
+
+	argv0 = *argv, argv0 ? (argc--, argv++) : (void *)0;
+
+	for (; *argv && (*argv)[0] == '-'; argc--, argv++) {
+		if (!(*argv)[1])
+			usage();
+		for (i = 1; (*argv)[i]; i++) {
+			switch ((*argv)[i]) {
+			case 'R':
+				r.maxdepth = 0;
+				break;
+			case 'r': case 'w': case 'x': case 'X': case 's': case 't':
+				/* -[rwxXst] are valid modes, so we're done */
+				if (i == 1)
+					goto done;
+				/* fallthrough */
+			case '-':
+				/* -- terminator */
+				if (i == 1 && !(*argv)[i + 1]) {
+					argv++;
+					argc--;
+					goto done;
+				}
+				/* fallthrough */
+			default:
+				usage();
+			}
+		}
+	}
+done:
+	mask = getumask();
+	modestr = *argv;
+
+	if (argc < 2)
+		usage();
+
+	for (--argc, ++argv; *argv; argc--, argv++)
+		recurse(AT_FDCWD, *argv, NULL, &r);
+
+	return ret || recurse_status;
+}