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/cut.c

@@ -0,0 +1,215 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "text.h"
+#include "utf.h"
+#include "util.h"
+
+typedef struct Range {
+	size_t min, max;
+	struct Range *next;
+} Range;
+
+static Range *list     = NULL;
+static char   mode     = 0;
+static char  *delim    = "\t";
+static size_t delimlen = 1;
+static int    nflag    = 0;
+static int    sflag    = 0;
+
+static void
+insert(Range *r)
+{
+	Range *l, *p, *t;
+
+	for (p = NULL, l = list; l; p = l, l = l->next) {
+		if (r->max && r->max + 1 < l->min) {
+			r->next = l;
+			break;
+		} else if (!l->max || r->min < l->max + 2) {
+			l->min = MIN(r->min, l->min);
+			for (p = l, t = l->next; t; p = t, t = t->next)
+				if (r->max && r->max + 1 < t->min)
+					break;
+			l->max = (p->max && r->max) ? MAX(p->max, r->max) : 0;
+			l->next = t;
+			return;
+		}
+	}
+	if (p)
+		p->next = r;
+	else
+		list = r;
+}
+
+static void
+parselist(char *str)
+{
+	char *s;
+	size_t n = 1;
+	Range *r;
+
+	if (!*str)
+		eprintf("empty list\n");
+	for (s = str; *s; s++) {
+		if (*s == ' ')
+			*s = ',';
+		if (*s == ',')
+			n++;
+	}
+	r = ereallocarray(NULL, n, sizeof(*r));
+	for (s = str; n; n--, s++) {
+		r->min = (*s == '-') ? 1 : strtoul(s, &s, 10);
+		r->max = (*s == '-') ? strtoul(s + 1, &s, 10) : r->min;
+		r->next = NULL;
+		if (!r->min || (r->max && r->max < r->min) || (*s && *s != ','))
+			eprintf("bad list value\n");
+		insert(r++);
+	}
+}
+
+static size_t
+seek(struct line *s, size_t pos, size_t *prev, size_t count)
+{
+	size_t n = pos - *prev, i, j;
+
+	if (mode == 'b') {
+		if (n >= s->len)
+			return s->len;
+		if (nflag)
+			while (n && !UTF8_POINT(s->data[n]))
+				n--;
+		*prev += n;
+		return n;
+	} else if (mode == 'c') {
+		for (n++, i = 0; i < s->len; i++)
+			if (UTF8_POINT(s->data[i]) && !--n)
+				break;
+	} else {
+		for (i = (count < delimlen + 1) ? 0 : delimlen; n && i < s->len; ) {
+			if ((s->len - i) >= delimlen &&
+			    !memcmp(s->data + i, delim, delimlen)) {
+				if (!--n && count)
+					break;
+				i += delimlen;
+				continue;
+			}
+			for (j = 1; j + i <= s->len && !fullrune(s->data + i, j); j++);
+			i += j;
+		}
+	}
+	*prev = pos;
+
+	return i;
+}
+
+static void
+cut(FILE *fp, const char *fname)
+{
+	Range *r;
+	struct line s;
+	static struct line line;
+	static size_t size;
+	size_t i, n, p;
+	ssize_t len;
+
+	while ((len = getline(&line.data, &size, fp)) > 0) {
+		line.len = len;
+		if (line.data[line.len - 1] == '\n')
+			line.data[--line.len] = '\0';
+		if (mode == 'f' && !memmem(line.data, line.len, delim, delimlen)) {
+			if (!sflag) {
+				fwrite(line.data, 1, line.len, stdout);
+				fputc('\n', stdout);
+			}
+			continue;
+		}
+		for (i = 0, p = 1, s = line, r = list; r; r = r->next) {
+			n = seek(&s, r->min, &p, i);
+			s.data += n;
+			s.len -= n;
+			i += (mode == 'f') ? delimlen : 1;
+			if (!s.len)
+				break;
+			if (!r->max) {
+				fwrite(s.data, 1, s.len, stdout);
+				break;
+			}
+			n = seek(&s, r->max + 1, &p, i);
+			i += (mode == 'f') ? delimlen : 1;
+			if (fwrite(s.data, 1, n, stdout) != n)
+				eprintf("fwrite <stdout>:");
+			s.data += n;
+			s.len -= n;
+		}
+		putchar('\n');
+	}
+	if (ferror(fp))
+		eprintf("getline %s:", fname);
+}
+
+static void
+usage(void)
+{
+	eprintf("usage: %s -b list [-n] [file ...]\n"
+	        "       %s -c list [file ...]\n"
+	        "       %s -f list [-d delim] [-s] [file ...]\n",
+		argv0, argv0, argv0);
+}
+
+int
+main(int argc, char *argv[])
+{
+	FILE *fp;
+	int ret = 0;
+
+	ARGBEGIN {
+	case 'b':
+	case 'c':
+	case 'f':
+		mode = ARGC();
+		parselist(EARGF(usage()));
+		break;
+	case 'd':
+		delim = EARGF(usage());
+		if (!*delim)
+			eprintf("empty delimiter\n");
+		delimlen = unescape(delim);
+		break;
+	case 'n':
+		nflag = 1;
+		break;
+	case 's':
+		sflag = 1;
+		break;
+	default:
+		usage();
+	} ARGEND
+
+	if (!mode)
+		usage();
+
+	if (!argc)
+		cut(stdin, "<stdin>");
+	else {
+		for (; *argv; argc--, argv++) {
+			if (!strcmp(*argv, "-")) {
+				*argv = "<stdin>";
+				fp = stdin;
+			} else if (!(fp = fopen(*argv, "r"))) {
+				weprintf("fopen %s:", *argv);
+				ret = 1;
+				continue;
+			}
+			cut(fp, *argv);
+			if (fp != stdin && fshut(fp, *argv))
+				ret = 1;
+		}
+	}
+
+	ret |= fshut(stdin, "<stdin>") | fshut(stdout, "<stdout>");
+
+	return ret;
+}