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>

1 files changed, 147 insertions, 0 deletions

diff --git a/util/sbase/seq.c b/util/sbase/seq.c
new file mode 100644
index 00000000..70763d1e
--- /dev/null
+++ b/util/sbase/seq.c
@@ -0,0 +1,147 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "util.h"
+
+static int
+digitsleft(const char *d)
+{
+	int shift;
+	char *exp;
+
+	if (*d == '+')
+		d++;
+	exp = strpbrk(d, "eE");
+	shift = exp ? estrtonum(exp + 1, INT_MIN, INT_MAX) : 0;
+
+	return MAX(0, strspn(d, "-0123456789") + shift);
+}
+
+static int
+digitsright(const char *d)
+{
+	int shift, after;
+	char *exp;
+
+	exp = strpbrk(d, "eE");
+	shift = exp ? estrtonum(&exp[1], INT_MIN, INT_MAX) : 0;
+	after = (d = strchr(d, '.')) ? strspn(&d[1], "0123456789") : 0;
+
+	return MAX(0, after - shift);
+}
+
+static int
+validfmt(const char *fmt)
+{
+	int occur = 0;
+
+literal:
+	while (*fmt)
+		if (*fmt++ == '%')
+			goto format;
+	return occur == 1;
+
+format:
+	if (*fmt == '%') {
+		fmt++;
+		goto literal;
+	}
+	fmt += strspn(fmt, "-+#0 '");
+	fmt += strspn(fmt, "0123456789");
+	if (*fmt == '.') {
+		fmt++;
+		fmt += strspn(fmt, "0123456789");
+	}
+	if (*fmt == 'L')
+		fmt++;
+
+	switch (*fmt) {
+	case 'f': case 'F':
+	case 'g': case 'G':
+	case 'e': case 'E':
+	case 'a': case 'A':
+		occur++;
+		goto literal;
+	default:
+		return 0;
+	}
+}
+
+static void
+usage(void)
+{
+	eprintf("usage: %s [-f fmt] [-s sep] [-w] "
+	        "[startnum [step]] endnum\n", argv0);
+}
+
+int
+main(int argc, char *argv[])
+{
+	double start, step, end, out, dir;
+	int wflag = 0, left, right;
+	char *tmp, ftmp[BUFSIZ], *fmt = ftmp;
+	const char *starts = "1", *steps = "1", *ends = "1", *sep = "\n";
+
+	ARGBEGIN {
+	case 'f':
+		if (!validfmt(tmp=EARGF(usage())))
+			eprintf("%s: invalid format\n", tmp);
+		fmt = tmp;
+		break;
+	case 's':
+		sep = EARGF(usage());
+		break;
+	case 'w':
+		wflag = 1;
+		break;
+	default:
+		usage();
+	} ARGEND
+
+	switch (argc) {
+	case 3:
+		steps = argv[1];
+		argv[1] = argv[2];
+		/* fallthrough */
+	case 2:
+		starts = argv[0];
+		argv++;
+		/* fallthrough */
+	case 1:
+		ends = argv[0];
+		break;
+	default:
+		usage();
+	}
+	start = estrtod(starts);
+	step  = estrtod(steps);
+	end   = estrtod(ends);
+
+	dir = (step > 0) ? 1.0 : -1.0;
+	if (step == 0 || start * dir > end * dir)
+		return 1;
+
+	if (fmt == ftmp) {
+		right = MAX(digitsright(starts),
+		            MAX(digitsright(ends),
+		                digitsright(steps)));
+
+		if (wflag) {
+			left = MAX(digitsleft(starts), digitsleft(ends));
+
+			snprintf(ftmp, sizeof ftmp, "%%0%d.%df",
+					right + left + (right != 0), right);
+		} else
+			snprintf(ftmp, sizeof ftmp, "%%.%df", right);
+	}
+	for (out = start; out * dir <= end * dir; out += step) {
+		if (out != start)
+			fputs(sep, stdout);
+		printf(fmt, out);
+	}
+	putchar('\n');
+
+	return fshut(stdout, "<stdout>");
+}