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authorLeah Rowe <leah@libreboot.org>2025-10-04 09:14:33 +0100
committerLeah Rowe <leah@libreboot.org>2025-10-04 09:20:12 +0100
commite9a910b33c7837b4b868e3abda18eb4810df7f02 (patch)
tree749e1830cb0607952df1a1afc0ae09ec1db54140 /util/sbase/date.c
parent2cfaba181b3c68761871fa47b32725c934423c14 (diff)
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>
Diffstat (limited to 'util/sbase/date.c')
-rw-r--r--util/sbase/date.c103
1 files changed, 103 insertions, 0 deletions
diff --git a/util/sbase/date.c b/util/sbase/date.c
new file mode 100644
index 00000000..109f3710
--- /dev/null
+++ b/util/sbase/date.c
@@ -0,0 +1,103 @@
+/* See LICENSE file for copyright and license details. */
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#include "util.h"
+
+static void
+usage(void)
+{
+ eprintf("usage: %s [-u] [-d time] [+format | mmddHHMM[[CC]yy]]\n", argv0);
+}
+
+static int
+datefield(const char *s, size_t i)
+{
+ if (!isdigit(s[i]) || !isdigit(s[i+1]))
+ eprintf("invalid date format: %s\n", s);
+
+ return (s[i] - '0') * 10 + (s[i+1] - '0');
+}
+
+static void
+setdate(const char *s, struct tm *now)
+{
+ struct tm date;
+ struct timespec ts;
+
+ switch (strlen(s)) {
+ case 8:
+ date.tm_year = now->tm_year;
+ break;
+ case 10:
+ date.tm_year = datefield(s, 8);
+ if (date.tm_year < 69)
+ date.tm_year += 100;
+ break;
+ case 12:
+ date.tm_year = ((datefield(s, 8) - 19) * 100) + datefield(s, 10);
+ break;
+ default:
+ eprintf("invalid date format: %s\n", s);
+ break;
+ }
+
+ date.tm_mon = datefield(s, 0) - 1;
+ date.tm_mday = datefield(s, 2);
+ date.tm_hour = datefield(s, 4);
+ date.tm_min = datefield(s, 6);
+ date.tm_sec = 0;
+ date.tm_isdst = -1;
+
+ ts.tv_sec = mktime(&date);
+ if (ts.tv_sec == -1)
+ eprintf("mktime:");
+ ts.tv_nsec = 0;
+
+ if (clock_settime(CLOCK_REALTIME, &ts) == -1)
+ eprintf("clock_settime:");
+}
+
+int
+main(int argc, char *argv[])
+{
+ struct tm *now;
+ time_t t;
+ char buf[BUFSIZ], *fmt = "%a %b %e %H:%M:%S %Z %Y";
+
+ t = time(NULL);
+ if (t == -1)
+ eprintf("time:");
+
+ ARGBEGIN {
+ case 'd':
+ t = estrtonum(EARGF(usage()), 0, LLONG_MAX);
+ break;
+ case 'u':
+ if (setenv("TZ", "UTC0", 1) < 0)
+ eprintf("setenv:");
+ break;
+ default:
+ usage();
+ } ARGEND
+
+ if (!(now = localtime(&t)))
+ eprintf("localtime:");
+ if (argc) {
+ if (argc != 1)
+ usage();
+ if (argv[0][0] != '+') {
+ setdate(argv[0], now);
+ return 0;
+ }
+ fmt = &argv[0][1];
+ }
+
+ strftime(buf, sizeof(buf), fmt, now);
+ puts(buf);
+
+ return fshut(stdout, "<stdout>");
+}