diff options
Diffstat (limited to '')
| -rw-r--r-- | libc-top-half/musl/src/time/strftime.c | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/libc-top-half/musl/src/time/strftime.c b/libc-top-half/musl/src/time/strftime.c new file mode 100644 index 0000000..a1db9cb --- /dev/null +++ b/libc-top-half/musl/src/time/strftime.c @@ -0,0 +1,285 @@ +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <langinfo.h> +#include <locale.h> +#include <time.h> +#include <limits.h> +#include "locale_impl.h" +#include "time_impl.h" + +static int is_leap(int y) +{ + /* Avoid overflow */ + if (y>INT_MAX-1900) y -= 2000; + y += 1900; + return !(y%4) && ((y%100) || !(y%400)); +} + +static int week_num(const struct tm *tm) +{ + int val = (tm->tm_yday + 7U - (tm->tm_wday+6U)%7) / 7; + /* If 1 Jan is just 1-3 days past Monday, + * the previous week is also in this year. */ + if ((tm->tm_wday + 371U - tm->tm_yday - 2) % 7 <= 2) + val++; + if (!val) { + val = 52; + /* If 31 December of prev year a Thursday, + * or Friday of a leap year, then the + * prev year has 53 weeks. */ + int dec31 = (tm->tm_wday + 7U - tm->tm_yday - 1) % 7; + if (dec31 == 4 || (dec31 == 5 && is_leap(tm->tm_year%400-1))) + val++; + } else if (val == 53) { + /* If 1 January is not a Thursday, and not + * a Wednesday of a leap year, then this + * year has only 52 weeks. */ + int jan1 = (tm->tm_wday + 371U - tm->tm_yday) % 7; + if (jan1 != 4 && (jan1 != 3 || !is_leap(tm->tm_year))) + val = 1; + } + return val; +} + +const char *__strftime_fmt_1(char (*s)[100], size_t *l, int f, const struct tm *tm, locale_t loc, int pad) +{ + nl_item item; + long long val; + const char *fmt = "-"; + int width = 2, def_pad = '0'; + + switch (f) { + case 'a': + if (tm->tm_wday > 6U) goto string; + item = ABDAY_1 + tm->tm_wday; + goto nl_strcat; + case 'A': + if (tm->tm_wday > 6U) goto string; + item = DAY_1 + tm->tm_wday; + goto nl_strcat; + case 'h': + case 'b': + if (tm->tm_mon > 11U) goto string; + item = ABMON_1 + tm->tm_mon; + goto nl_strcat; + case 'B': + if (tm->tm_mon > 11U) goto string; + item = MON_1 + tm->tm_mon; + goto nl_strcat; + case 'c': + item = D_T_FMT; + goto nl_strftime; + case 'C': + val = (1900LL+tm->tm_year) / 100; + goto number; + case 'e': + def_pad = '_'; + case 'd': + val = tm->tm_mday; + goto number; + case 'D': + fmt = "%m/%d/%y"; + goto recu_strftime; + case 'F': + fmt = "%Y-%m-%d"; + goto recu_strftime; + case 'g': + case 'G': + val = tm->tm_year + 1900LL; + if (tm->tm_yday < 3 && week_num(tm) != 1) val--; + else if (tm->tm_yday > 360 && week_num(tm) == 1) val++; + if (f=='g') val %= 100; + else width = 4; + goto number; + case 'H': + val = tm->tm_hour; + goto number; + case 'I': + val = tm->tm_hour; + if (!val) val = 12; + else if (val > 12) val -= 12; + goto number; + case 'j': + val = tm->tm_yday+1; + width = 3; + goto number; + case 'm': + val = tm->tm_mon+1; + goto number; + case 'M': + val = tm->tm_min; + goto number; + case 'n': + *l = 1; + return "\n"; + case 'p': + item = tm->tm_hour >= 12 ? PM_STR : AM_STR; + goto nl_strcat; + case 'r': + item = T_FMT_AMPM; + goto nl_strftime; + case 'R': + fmt = "%H:%M"; + goto recu_strftime; + case 's': + val = __tm_to_secs(tm) - tm->__tm_gmtoff; + width = 1; + goto number; + case 'S': + val = tm->tm_sec; + goto number; + case 't': + *l = 1; + return "\t"; + case 'T': + fmt = "%H:%M:%S"; + goto recu_strftime; + case 'u': + val = tm->tm_wday ? tm->tm_wday : 7; + width = 1; + goto number; + case 'U': + val = (tm->tm_yday + 7U - tm->tm_wday) / 7; + goto number; + case 'W': + val = (tm->tm_yday + 7U - (tm->tm_wday+6U)%7) / 7; + goto number; + case 'V': + val = week_num(tm); + goto number; + case 'w': + val = tm->tm_wday; + width = 1; + goto number; + case 'x': + item = D_FMT; + goto nl_strftime; + case 'X': + item = T_FMT; + goto nl_strftime; + case 'y': + val = (tm->tm_year + 1900LL) % 100; + if (val < 0) val = -val; + goto number; + case 'Y': + val = tm->tm_year + 1900LL; + if (val >= 10000) { + *l = snprintf(*s, sizeof *s, "+%lld", val); + return *s; + } + width = 4; + goto number; + case 'z': + if (tm->tm_isdst < 0) { + *l = 0; + return ""; + } +#ifdef __wasilibc_unmodified_upstream // wasi-libc's __tm_gmtoff is an int + *l = snprintf(*s, sizeof *s, "%+.4ld", +#else + *l = snprintf(*s, sizeof *s, "%+.4d", +#endif + tm->__tm_gmtoff/3600*100 + tm->__tm_gmtoff%3600/60); + return *s; + case 'Z': + if (tm->tm_isdst < 0) { + *l = 0; + return ""; + } + fmt = __tm_to_tzname(tm); + goto string; + case '%': + *l = 1; + return "%"; + default: + return 0; + } +number: + switch (pad ? pad : def_pad) { + case '-': *l = snprintf(*s, sizeof *s, "%lld", val); break; + case '_': *l = snprintf(*s, sizeof *s, "%*lld", width, val); break; + case '0': + default: *l = snprintf(*s, sizeof *s, "%0*lld", width, val); break; + } + return *s; +nl_strcat: + fmt = __nl_langinfo_l(item, loc); +string: + *l = strlen(fmt); + return fmt; +nl_strftime: + fmt = __nl_langinfo_l(item, loc); +recu_strftime: + *l = __strftime_l(*s, sizeof *s, fmt, tm, loc); + if (!*l) return 0; + return *s; +} + +size_t __strftime_l(char *restrict s, size_t n, const char *restrict f, const struct tm *restrict tm, locale_t loc) +{ + size_t l, k; + char buf[100]; + char *p; + const char *t; + int pad, plus; + unsigned long width; + for (l=0; l<n; f++) { + if (!*f) { + s[l] = 0; + return l; + } + if (*f != '%') { + s[l++] = *f; + continue; + } + f++; + pad = 0; + if (*f == '-' || *f == '_' || *f == '0') pad = *f++; + if ((plus = (*f == '+'))) f++; + width = strtoul(f, &p, 10); + if (*p == 'C' || *p == 'F' || *p == 'G' || *p == 'Y') { + if (!width && p!=f) width = 1; + } else { + width = 0; + } + f = p; + if (*f == 'E' || *f == 'O') f++; + t = __strftime_fmt_1(&buf, &k, *f, tm, loc, pad); + if (!t) break; + if (width) { + /* Trim off any sign and leading zeros, then + * count remaining digits to determine behavior + * for the + flag. */ + if (*t=='+' || *t=='-') t++, k--; + for (; *t=='0' && t[1]-'0'<10U; t++, k--); + if (width < k) width = k; + size_t d; + for (d=0; t[d]-'0'<10U; d++); + if (tm->tm_year < -1900) { + s[l++] = '-'; + width--; + } else if (plus && d+(width-k) >= (*p=='C'?3:5)) { + s[l++] = '+'; + width--; + } + for (; width > k && l < n; width--) + s[l++] = '0'; + } + if (k > n-l) k = n-l; + memcpy(s+l, t, k); + l += k; + } + if (n) { + if (l==n) l=n-1; + s[l] = 0; + } + return 0; +} + +size_t strftime(char *restrict s, size_t n, const char *restrict f, const struct tm *restrict tm) +{ + return __strftime_l(s, n, f, tm, CURRENT_LOCALE); +} + +weak_alias(__strftime_l, strftime_l); |