From: Thomas Weißschuh <thomas@t-8ch.de>
Date: Tue, 4 Jul 2023 07:45:55 +0000 (+0200)
Subject: timeutils: add strtimespec_relative
X-Git-Tag: v2.40-rc1~346^2~3
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=00ddcaf19c60471b9390a12f65a56c5c0f6877cf;p=thirdparty%2Futil-linux.git

timeutils: add strtimespec_relative

Signed-off-by: Thomas Weißschuh <thomas@t-8ch.de>
---

diff --git a/include/timeutils.h b/include/timeutils.h
index 4257bd1eda..27261abd87 100644
--- a/include/timeutils.h
+++ b/include/timeutils.h
@@ -78,6 +78,7 @@ int strtimeval_iso(const struct timeval *tv, int flags, char *buf, size_t bufsz)
 int strtm_iso(const struct tm *tm, int flags, char *buf, size_t bufsz);
 int strtime_iso(const time_t *t, int flags, char *buf, size_t bufsz);
 int strtimespec_iso(const struct timespec *t, int flags, char *buf, size_t bufsz);
+int strtimespec_relative(const struct timespec *ts, char *buf, size_t bufsz);
 
 #define UL_SHORTTIME_THISYEAR_HHMM (1 << 1)
 
diff --git a/lib/timeutils.c b/lib/timeutils.c
index c1ffc547c0..8f9c8e9be8 100644
--- a/lib/timeutils.c
+++ b/lib/timeutils.c
@@ -617,6 +617,63 @@ int strtime_short(const time_t *t, struct timeval *now, int flags, char *buf, si
 	return rc <= 0 ? -1 : 0;
 }
 
+int strtimespec_relative(const struct timespec *ts, char *buf, size_t bufsz)
+{
+	time_t secs = ts->tv_sec;
+	size_t i, parts = 0;
+	int rc;
+
+	if (bufsz)
+		buf[0] = '\0';
+
+	static const struct {
+		const char * const suffix;
+		int width;
+		int64_t secs;
+	} table[] = {
+		{ "y", 4, NSEC_PER_YEAR   / NSEC_PER_SEC },
+		{ "d", 3, NSEC_PER_DAY    / NSEC_PER_SEC },
+		{ "h", 2, NSEC_PER_HOUR   / NSEC_PER_SEC },
+		{ "m", 2, NSEC_PER_MINUTE / NSEC_PER_SEC },
+		{ "s", 2, NSEC_PER_SEC    / NSEC_PER_SEC },
+	};
+
+	for (i = 0; i < ARRAY_SIZE(table); i++) {
+		if (secs >= table[i].secs) {
+			rc = snprintf(buf, bufsz,
+				      "%*"PRId64"%s%s",
+				      parts ? table[i].width : 0,
+				      secs / table[i].secs, table[i].suffix,
+				      secs % table[i].secs ? " " : "");
+			if (rc < 0 || (size_t) rc > bufsz)
+				goto err;
+			parts++;
+			buf += rc;
+			bufsz -= rc;
+			secs %= table[i].secs;
+		}
+	}
+
+	if (ts->tv_nsec) {
+		if (ts->tv_nsec % NSEC_PER_MSEC) {
+			rc = snprintf(buf, bufsz, "%*luns",
+				      parts ? 10 : 0, ts->tv_nsec);
+			if (rc < 0 || (size_t) rc > bufsz)
+				goto err;
+		} else {
+			rc = snprintf(buf, bufsz, "%*llums",
+				      parts ? 4 : 0, ts->tv_nsec / NSEC_PER_MSEC);
+			if (rc < 0 || (size_t) rc > bufsz)
+				goto err;
+		}
+	}
+
+	return 0;
+ err:
+	warnx(_("format_reltime: buffer overflow."));
+	return -1;
+}
+
 #ifndef HAVE_TIMEGM
 time_t timegm(struct tm *tm)
 {
@@ -727,6 +784,53 @@ static int run_unittest_format(void)
 	return rc;
 }
 
+static int run_unittest_format_relative(void)
+{
+	int rc = EXIT_SUCCESS;
+	char buf[FORMAT_TIMESTAMP_MAX];
+	static const struct testcase {
+		struct timespec ts;
+		const char * const expected;
+	} testcases[] = {
+		{{}, "" },
+		{{         1 },                  "1s" },
+		{{        10 },                 "10s" },
+		{{       100 },              "1m 40s" },
+		{{      1000 },             "16m 40s" },
+		{{     10000 },          "2h 46m 40s" },
+		{{    100000 },      "1d  3h 46m 40s" },
+		{{   1000000 },     "11d 13h 46m 40s" },
+		{{  10000000 },    "115d 17h 46m 40s" },
+		{{ 100000000 }, "3y  61d 15h 46m 40s" },
+		{{        60 },                  "1m" },
+		{{      3600 },                  "1h" },
+
+		{{ 1,       1 }, "1s         1ns" },
+		{{ 0,       1 },            "1ns" },
+		{{ 0, 1000000 },            "1ms" },
+		{{ 0, 1000001 },      "1000001ns" },
+	};
+
+	setenv("TZ", "GMT", 1);
+	tzset();
+
+	for (size_t i = 0; i < ARRAY_SIZE(testcases); i++) {
+		struct testcase t = testcases[i];
+		int r = strtimespec_relative(&t.ts, buf, sizeof(buf));
+		if (r) {
+			fprintf(stderr, "Could not format '%s'\n", t.expected);
+			rc = EXIT_FAILURE;
+		}
+
+		if (strcmp(buf, t.expected)) {
+			fprintf(stderr, "#%02zu '%-20s' != '%-20s'\n", i, buf, t.expected);
+			rc = EXIT_FAILURE;
+		}
+	}
+
+	return rc;
+}
+
 int main(int argc, char *argv[])
 {
 	struct timespec ts = { 0 };
@@ -741,6 +845,8 @@ int main(int argc, char *argv[])
 		return run_unittest_timestamp();
 	else if (strcmp(argv[1], "--unittest-format") == 0)
 		return run_unittest_format();
+	else if (strcmp(argv[1], "--unittest-format-relative") == 0)
+		return run_unittest_format_relative();
 
 	if (strcmp(argv[1], "--timestamp") == 0) {
 		usec_t usec = 0;
@@ -768,6 +874,9 @@ int main(int argc, char *argv[])
 	strtimespec_iso(&ts, ISO_TIMESTAMP_DOT, buf, sizeof(buf));
 	printf("Zone: '%s'\n", buf);
 
+	strtimespec_relative(&ts, buf, sizeof(buf));
+	printf("Rel:  '%s'\n", buf);
+
 	return EXIT_SUCCESS;
 }
 
diff --git a/tests/ts/lib/timeutils b/tests/ts/lib/timeutils
index 74bb17b8e1..043b0c0e13 100755
--- a/tests/ts/lib/timeutils
+++ b/tests/ts/lib/timeutils
@@ -23,4 +23,8 @@ ts_init_subtest "format"
 "$TS_HELPER_TIMEUTILS" --unittest-format 2> "$TS_ERRLOG" || ts_die "test failed"
 ts_finalize_subtest
 
+ts_init_subtest "format-relative"
+"$TS_HELPER_TIMEUTILS" --unittest-format-relative 2> "$TS_ERRLOG" || ts_die "test failed"
+ts_finalize_subtest
+
 ts_finalize