8 #include "locale_impl.h"
10 #include "time_impl.h"
12 static int is_leap(int y)
15 if (y>INT_MAX-1900) y -= 2000;
17 return !(y%4) && ((y%100) || !(y%400));
20 static int week_num(const struct tm *tm)
22 int val = (tm->tm_yday + 7U - (tm->tm_wday+6U)%7) / 7;
23 /* If 1 Jan is just 1-3 days past Monday,
24 * the previous week is also in this year. */
25 if ((tm->tm_wday + 371U - tm->tm_yday - 2) % 7 <= 2)
29 /* If 31 December of prev year a Thursday,
30 * or Friday of a leap year, then the
31 * prev year has 53 weeks. */
32 int dec31 = (tm->tm_wday + 7U - tm->tm_yday - 1) % 7;
33 if (dec31 == 4 || (dec31 == 5 && is_leap(tm->tm_year%400-1)))
35 } else if (val == 53) {
36 /* If 1 January is not a Thursday, and not
37 * a Wednesday of a leap year, then this
38 * year has only 52 weeks. */
39 int jan1 = (tm->tm_wday + 371U - tm->tm_yday) % 7;
40 if (jan1 != 4 && (jan1 != 3 || !is_leap(tm->tm_year)))
46 const char *__strftime_fmt_1(char (*s)[100], size_t *l, int f, const struct tm *tm, locale_t loc, int pad)
50 const char *fmt = "-";
51 int width = 2, def_pad = '0';
55 if (tm->tm_wday > 6U) goto string;
56 item = ABDAY_1 + tm->tm_wday;
59 if (tm->tm_wday > 6U) goto string;
60 item = DAY_1 + tm->tm_wday;
64 if (tm->tm_mon > 11U) goto string;
65 item = ABMON_1 + tm->tm_mon;
68 if (tm->tm_mon > 11U) goto string;
69 item = MON_1 + tm->tm_mon;
75 val = (1900LL+tm->tm_year) / 100;
90 val = tm->tm_year + 1900LL;
91 if (tm->tm_yday < 3 && week_num(tm) != 1) val--;
92 else if (tm->tm_yday > 360 && week_num(tm) == 1) val++;
93 if (f=='g') val %= 100;
102 else if (val > 12) val -= 12;
118 item = tm->tm_hour >= 12 ? PM_STR : AM_STR;
127 val = __tm_to_secs(tm) - tm->__tm_gmtoff;
140 val = tm->tm_wday ? tm->tm_wday : 7;
144 val = (tm->tm_yday + 7U - tm->tm_wday) / 7;
147 val = (tm->tm_yday + 7U - (tm->tm_wday+6U)%7) / 7;
163 val = (tm->tm_year + 1900LL) % 100;
164 if (val < 0) val = -val;
167 val = tm->tm_year + 1900LL;
169 *l = snprintf(*s, sizeof *s, "+%lld", val);
175 if (tm->tm_isdst < 0) {
179 *l = snprintf(*s, sizeof *s, "%+.4ld",
180 tm->__tm_gmtoff/3600*100 + tm->__tm_gmtoff%3600/60);
183 if (tm->tm_isdst < 0) {
187 fmt = __tm_to_tzname(tm);
196 switch (pad ? pad : def_pad) {
197 case '-': *l = snprintf(*s, sizeof *s, "%lld", val); break;
198 case '_': *l = snprintf(*s, sizeof *s, "%*lld", width, val); break;
200 default: *l = snprintf(*s, sizeof *s, "%0*lld", width, val); break;
204 fmt = __nl_langinfo_l(item, loc);
209 fmt = __nl_langinfo_l(item, loc);
211 *l = __strftime_l(*s, sizeof *s, fmt, tm, loc);
216 size_t __strftime_l(char *restrict s, size_t n, const char *restrict f, const struct tm *restrict tm, locale_t loc)
224 for (l=0; l<n; f++) {
235 if (*f == '-' || *f == '_' || *f == '0') pad = *f++;
236 if ((plus = (*f == '+'))) f++;
237 width = strtoul(f, &p, 10);
238 if (*p == 'C' || *p == 'F' || *p == 'G' || *p == 'Y') {
239 if (!width && p!=f) width = 1;
244 if (*f == 'E' || *f == 'O') f++;
245 t = __strftime_fmt_1(&buf, &k, *f, tm, loc, pad);
248 /* Trim off any sign and leading zeros, then
249 * count remaining digits to determine behavior
251 if (*t=='+' || *t=='-') t++, k--;
252 for (; *t=='0' && t[1]-'0'<10U; t++, k--);
253 if (width < k) width = k;
255 for (d=0; t[d]-'0'<10U; d++);
256 if (tm->tm_year < -1900) {
259 } else if (plus && d+(width-k) >= (*p=='C'?3:5)) {
263 for (; width > k && l < n; width--)
266 if (k > n-l) k = n-l;
277 size_t strftime(char *restrict s, size_t n, const char *restrict f, const struct tm *restrict tm)
279 return __strftime_l(s, n, f, tm, CURRENT_LOCALE);
282 weak_alias(__strftime_l, strftime_l);