1 /*
2 * Copyright (c) 2024 Meta Platforms
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <stdio.h>
8 #include <string.h>
9 #include <time.h>
10
11 #include <zephyr/sys/util.h>
12
13 #define DATE_STRING_BUF_SZ 26U
14 #define DATE_WDAY_STRING_SZ 7U
15 #define DATE_MON_STRING_SZ 12U
16 #define DATE_TM_YEAR_BASE 1900
17
asctime_impl(const struct tm * tp,char * buf)18 static char *asctime_impl(const struct tm *tp, char *buf)
19 {
20 static const char wday_str[DATE_WDAY_STRING_SZ][3] = {
21 "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat",
22 };
23 static const char mon_str[DATE_MON_STRING_SZ][3] = {
24 "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec",
25 };
26
27 if ((buf == NULL) || (tp == NULL) || ((unsigned int)tp->tm_wday >= DATE_WDAY_STRING_SZ) ||
28 ((unsigned int)tp->tm_mon >= DATE_MON_STRING_SZ)) {
29 return NULL;
30 }
31
32 unsigned int n = (unsigned int)snprintf(
33 buf, DATE_STRING_BUF_SZ, "%.3s %.3s%3d %.2d:%.2d:%.2d %d\n", wday_str[tp->tm_wday],
34 mon_str[tp->tm_mon], tp->tm_mday, tp->tm_hour, tp->tm_min, tp->tm_sec,
35 DATE_TM_YEAR_BASE + tp->tm_year);
36
37 if (n >= DATE_STRING_BUF_SZ) {
38 return NULL;
39 }
40
41 return buf;
42 }
43
asctime(const struct tm * tp)44 char *asctime(const struct tm *tp)
45 {
46 static char buf[DATE_STRING_BUF_SZ];
47
48 return asctime_impl(tp, buf);
49 }
50
51 #if defined(CONFIG_COMMON_LIBC_ASCTIME_R)
asctime_r(const struct tm * tp,char * buf)52 char *asctime_r(const struct tm *tp, char *buf)
53 {
54 return asctime_impl(tp, buf);
55 }
56 #endif /* CONFIG_COMMON_LIBC_ASCTIME_R */
57
