2 * Copyright (c) 1999 - 2002 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of KTH nor the names of its contributors may be
18 * used to endorse or promote products derived from this software without
19 * specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY KTH AND ITS CONTRIBUTORS ``AS IS'' AND ANY
22 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL KTH OR ITS CONTRIBUTORS BE
25 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
28 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
31 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
38 RCSID("$Id: strftime.c,v 1.13 2002/08/20 12:42:37 joda Exp $");
40 static const char *abb_weekdays[] = {
50 static const char *full_weekdays[] = {
60 static const char *abb_month[] = {
75 static const char *full_month[] = {
90 static const char *ampm[] = {
96 * Convert hour in [0, 24] to [12 1 - 11 12 1 - 11 12]
100 hour_24to12 (int hour)
110 * Return AM or PM for `hour'
114 hour_to_ampm (int hour)
116 return ampm[hour / 12];
120 * Return the week number of `tm' (Sunday being the first day of the week)
125 week_number_sun (const struct tm *tm)
127 return (tm->tm_yday + 7 - (tm->tm_yday % 7 - tm->tm_wday + 7) % 7) / 7;
131 * Return the week number of `tm' (Monday being the first day of the week)
136 week_number_mon (const struct tm *tm)
138 int wday = (tm->tm_wday + 6) % 7;
140 return (tm->tm_yday + 7 - (tm->tm_yday % 7 - wday + 7) % 7) / 7;
144 * Return the week number of `tm' (Monday being the first day of the
145 * week) as [01, 53]. Week number one is the one that has four or more
150 week_number_mon4 (const struct tm *tm)
152 int wday = (tm->tm_wday + 6) % 7;
153 int w1day = (wday - tm->tm_yday % 7 + 7) % 7;
156 ret = (tm->tm_yday + w1day) / 7;
171 strftime (char *buf, size_t maxsize, const char *format,
177 while (*format != '\0' && n < maxsize) {
178 if (*format == '%') {
180 if(*format == 'E' || *format == 'O')
184 ret = snprintf (buf, maxsize - n,
185 "%s", abb_weekdays[tm->tm_wday]);
188 ret = snprintf (buf, maxsize - n,
189 "%s", full_weekdays[tm->tm_wday]);
193 ret = snprintf (buf, maxsize - n,
194 "%s", abb_month[tm->tm_mon]);
197 ret = snprintf (buf, maxsize - n,
198 "%s", full_month[tm->tm_mon]);
201 ret = snprintf (buf, maxsize - n,
202 "%d:%02d:%02d %02d:%02d:%02d",
211 ret = snprintf (buf, maxsize - n,
212 "%02d", (tm->tm_year + 1900) / 100);
215 ret = snprintf (buf, maxsize - n,
216 "%02d", tm->tm_mday);
219 ret = snprintf (buf, maxsize - n,
223 (tm->tm_year + 1900) % 100);
226 ret = snprintf (buf, maxsize - n,
230 ret = snprintf (buf, maxsize - n,
231 "%04d-%02d-%02d", tm->tm_year + 1900,
232 tm->tm_mon + 1, tm->tm_mday);
235 /* last two digits of week-based year */
238 /* week-based year */
241 ret = snprintf (buf, maxsize - n,
242 "%02d", tm->tm_hour);
245 ret = snprintf (buf, maxsize - n,
247 hour_24to12 (tm->tm_hour));
250 ret = snprintf (buf, maxsize - n,
251 "%03d", tm->tm_yday + 1);
254 ret = snprintf (buf, maxsize - n,
258 ret = snprintf (buf, maxsize - n,
260 hour_24to12 (tm->tm_hour));
263 ret = snprintf (buf, maxsize - n,
264 "%02d", tm->tm_mon + 1);
267 ret = snprintf (buf, maxsize - n,
271 ret = snprintf (buf, maxsize - n, "\n");
274 ret = snprintf (buf, maxsize - n, "%s",
275 hour_to_ampm (tm->tm_hour));
278 ret = snprintf (buf, maxsize - n,
280 hour_24to12 (tm->tm_hour),
283 hour_to_ampm (tm->tm_hour));
286 ret = snprintf (buf, maxsize - n,
292 ret = snprintf (buf, maxsize - n,
293 "%d", (int)mktime((struct tm *)tm));
296 ret = snprintf (buf, maxsize - n,
300 ret = snprintf (buf, maxsize - n, "\t");
304 ret = snprintf (buf, maxsize - n,
311 ret = snprintf (buf, maxsize - n,
312 "%d", (tm->tm_wday == 0) ? 7 : tm->tm_wday);
315 ret = snprintf (buf, maxsize - n,
316 "%02d", week_number_sun (tm));
319 ret = snprintf (buf, maxsize - n,
320 "%02d", week_number_mon4 (tm));
323 ret = snprintf (buf, maxsize - n,
327 ret = snprintf (buf, maxsize - n,
328 "%02d", week_number_mon (tm));
331 ret = snprintf (buf, maxsize - n,
338 ret = snprintf (buf, maxsize - n,
339 "%02d", (tm->tm_year + 1900) % 100);
342 ret = snprintf (buf, maxsize - n,
343 "%d", tm->tm_year + 1900);
346 ret = snprintf (buf, maxsize - n,
348 #if defined(HAVE_STRUCT_TM_TM_GMTOFF)
350 #elif defined(HAVE_TIMEZONE)
357 #error Where in timezone chaos are you?
362 ret = snprintf (buf, maxsize - n,
365 #if defined(HAVE_STRUCT_TM_TM_ZONE)
367 #elif defined(HAVE_TIMEZONE)
378 ret = snprintf (buf, maxsize - n,
382 ret = snprintf (buf, maxsize - n,
386 if (ret < 0 || ret >= maxsize - n)