1#include <stdio.h> 2#include <stdlib.h> 3#include <string.h> 4#include <langinfo.h> 5#include <locale.h> 6#include <time.h> 7#include <limits.h> 8#include "locale_impl.h" 9#include "libc.h" 10#include "time_impl.h" 11 12const char *__nl_langinfo_l(nl_item, locale_t); 13 14static int is_leap(int y) 15{ 16 /* Avoid overflow */ 17 if (y>INT_MAX-1900) y -= 2000; 18 y += 1900; 19 return !(y%4) && ((y%100) || !(y%400)); 20} 21 22static int week_num(const struct tm *tm) 23{ 24 int val = (tm->tm_yday + 7U - (tm->tm_wday+6U)%7) / 7; 25 /* If 1 Jan is just 1-3 days past Monday, 26 * the previous week is also in this year. */ 27 if ((tm->tm_wday + 371U - tm->tm_yday - 2) % 7 <= 2) 28 val++; 29 if (!val) { 30 val = 52; 31 /* If 31 December of prev year a Thursday, 32 * or Friday of a leap year, then the 33 * prev year has 53 weeks. */ 34 int dec31 = (tm->tm_wday + 7U - tm->tm_yday - 1) % 7; 35 if (dec31 == 4 || (dec31 == 5 && is_leap(tm->tm_year%400-1))) 36 val++; 37 } else if (val == 53) { 38 /* If 1 January is not a Thursday, and not 39 * a Wednesday of a leap year, then this 40 * year has only 52 weeks. */ 41 int jan1 = (tm->tm_wday + 371U - tm->tm_yday) % 7; 42 if (jan1 != 4 && (jan1 != 3 || !is_leap(tm->tm_year))) 43 val = 1; 44 } 45 return val; 46} 47 48const char *__tm_to_tzname(const struct tm *); 49size_t __strftime_l(char *restrict, size_t, const char *restrict, const struct tm *restrict, locale_t); 50 51const char *__strftime_fmt_1(char (*s)[100], size_t *l, int f, const struct tm *tm, locale_t loc) 52{ 53 nl_item item; 54 long long val; 55 const char *fmt = "-"; 56 int width = 2; 57 58 switch (f) { 59 case 'a': 60 if (tm->tm_wday > 6U) goto string; 61 item = ABDAY_1 + tm->tm_wday; 62 goto nl_strcat; 63 case 'A': 64 if (tm->tm_wday > 6U) goto string; 65 item = DAY_1 + tm->tm_wday; 66 goto nl_strcat; 67 case 'h': 68 case 'b': 69 if (tm->tm_mon > 11U) goto string; 70 item = ABMON_1 + tm->tm_mon; 71 goto nl_strcat; 72 case 'B': 73 if (tm->tm_mon > 11U) goto string; 74 item = MON_1 + tm->tm_mon; 75 goto nl_strcat; 76 case 'c': 77 item = D_T_FMT; 78 goto nl_strftime; 79 case 'C': 80 val = (1900LL+tm->tm_year) / 100; 81 goto number; 82 case 'd': 83 val = tm->tm_mday; 84 goto number; 85 case 'D': 86 fmt = "%m/%d/%y"; 87 goto recu_strftime; 88 case 'e': 89 *l = snprintf(*s, sizeof *s, "%2d", tm->tm_mday); 90 return *s; 91 case 'F': 92 fmt = "%Y-%m-%d"; 93 goto recu_strftime; 94 case 'g': 95 case 'G': 96 val = tm->tm_year + 1900LL; 97 if (tm->tm_yday < 3 && week_num(tm) != 1) val--; 98 else if (tm->tm_yday > 360 && week_num(tm) == 1) val++; 99 if (f=='g') val %= 100; 100 else width = 4; 101 goto number; 102 case 'H': 103 val = tm->tm_hour; 104 goto number; 105 case 'I': 106 val = tm->tm_hour; 107 if (!val) val = 12; 108 else if (val > 12) val -= 12; 109 goto number; 110 case 'j': 111 val = tm->tm_yday+1; 112 width = 3; 113 goto number; 114 case 'm': 115 val = tm->tm_mon+1; 116 goto number; 117 case 'M': 118 val = tm->tm_min; 119 goto number; 120 case 'n': 121 *l = 1; 122 return "\n"; 123 case 'p': 124 item = tm->tm_hour >= 12 ? PM_STR : AM_STR; 125 goto nl_strcat; 126 case 'r': 127 item = T_FMT_AMPM; 128 goto nl_strftime; 129 case 'R': 130 fmt = "%H:%M"; 131 goto recu_strftime; 132 case 's': 133 val = __tm_to_secs(tm) - tm->__tm_gmtoff; 134 width = 1; 135 goto number; 136 case 'S': 137 val = tm->tm_sec; 138 goto number; 139 case 't': 140 *l = 1; 141 return "\t"; 142 case 'T': 143 fmt = "%H:%M:%S"; 144 goto recu_strftime; 145 case 'u': 146 val = tm->tm_wday ? tm->tm_wday : 7; 147 width = 1; 148 goto number; 149 case 'U': 150 val = (tm->tm_yday + 7U - tm->tm_wday) / 7; 151 goto number; 152 case 'W': 153 val = (tm->tm_yday + 7U - (tm->tm_wday+6U)%7) / 7; 154 goto number; 155 case 'V': 156 val = week_num(tm); 157 goto number; 158 case 'w': 159 val = tm->tm_wday; 160 width = 1; 161 goto number; 162 case 'x': 163 item = D_FMT; 164 goto nl_strftime; 165 case 'X': 166 item = T_FMT; 167 goto nl_strftime; 168 case 'y': 169 val = tm->tm_year % 100; 170 if (val<0) val += 100; 171 goto number; 172 case 'Y': 173 val = tm->tm_year + 1900LL; 174 if (val >= 10000) { 175 *l = snprintf(*s, sizeof *s, "+%lld", val); 176 return *s; 177 } 178 width = 4; 179 goto number; 180 case 'z': 181 if (tm->tm_isdst < 0) { 182 *l = 0; 183 return ""; 184 } 185 *l = snprintf(*s, sizeof *s, "%+.2d%.2d", 186 (tm->__tm_gmtoff)/3600, 187 abs(tm->__tm_gmtoff%3600)/60); 188 return *s; 189 case 'Z': 190 if (tm->tm_isdst < 0) { 191 *l = 0; 192 return ""; 193 } 194 fmt = __tm_to_tzname(tm); 195 goto string; 196 case '%': 197 *l = 1; 198 return "%"; 199 default: 200 return 0; 201 } 202number: 203 *l = snprintf(*s, sizeof *s, "%0*lld", width, val); 204 return *s; 205nl_strcat: 206 fmt = __nl_langinfo_l(item, loc); 207string: 208 *l = strlen(fmt); 209 return fmt; 210nl_strftime: 211 fmt = __nl_langinfo_l(item, loc); 212recu_strftime: 213 *l = __strftime_l(*s, sizeof *s, fmt, tm, loc); 214 if (!*l) return 0; 215 return *s; 216} 217 218size_t __strftime_l(char *restrict s, size_t n, const char *restrict f, const struct tm *restrict tm, locale_t loc) 219{ 220 size_t l, k; 221 char buf[100]; 222 char *p; 223 const char *t; 224 int plus; 225 unsigned long width; 226 for (l=0; l<n; f++) { 227 if (!*f) { 228 s[l] = 0; 229 return l; 230 } 231 if (*f != '%') { 232 s[l++] = *f; 233 continue; 234 } 235 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; 240 } else { 241 width = 0; 242 } 243 f = p; 244 if (*f == 'E' || *f == 'O') f++; 245 t = __strftime_fmt_1(&buf, &k, *f, tm, loc); 246 if (!t) break; 247 if (width) { 248 for (; *t=='+' || *t=='-' || (*t=='0'&&t[1]); t++, k--); 249 width--; 250 if (plus && tm->tm_year >= 10000-1900) 251 s[l++] = '+'; 252 else if (tm->tm_year < -1900) 253 s[l++] = '-'; 254 else 255 width++; 256 for (; width > k && l < n; width--) 257 s[l++] = '0'; 258 } 259 if (k > n-l) k = n-l; 260 memcpy(s+l, t, k); 261 l += k; 262 } 263 if (n) { 264 if (l==n) l=n-1; 265 s[l] = 0; 266 } 267 return 0; 268} 269 270size_t strftime(char *restrict s, size_t n, const char *restrict f, const struct tm *restrict tm) 271{ 272 return __strftime_l(s, n, f, tm, CURRENT_LOCALE); 273} 274 275weak_alias(__strftime_l, strftime_l); 276