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/libutil/mkdirp.c

@@ -0,0 +1,39 @@
+/* See LICENSE file for copyright and license details. */
+#include <sys/stat.h>
+
+#include <errno.h>
+#include <limits.h>
+
+#include "../util.h"
+
+int
+mkdirp(const char *path, mode_t mode, mode_t pmode)
+{
+	char tmp[PATH_MAX], *p;
+	struct stat st;
+
+	if (stat(path, &st) == 0) {
+		if (S_ISDIR(st.st_mode))
+			return 0;
+		errno = ENOTDIR;
+		weprintf("%s:", path);
+		return -1;
+	}
+
+	estrlcpy(tmp, path, sizeof(tmp));
+	for (p = tmp + (tmp[0] == '/'); *p; p++) {
+		if (*p != '/')
+			continue;
+		*p = '\0';
+		if (mkdir(tmp, pmode) < 0 && errno != EEXIST) {
+			weprintf("mkdir %s:", tmp);
+			return -1;
+		}
+		*p = '/';
+	}
+	if (mkdir(tmp, mode) < 0 && errno != EEXIST) {
+		weprintf("mkdir %s:", tmp);
+		return -1;
+	}
+	return 0;
+}