begin refactoring strftime to make adding field widths easier
authorRich Felker <dalias@aerifal.cx>
Thu, 22 Aug 2013 23:02:52 +0000 (19:02 -0400)
committerRich Felker <dalias@aerifal.cx>
Thu, 22 Aug 2013 23:02:52 +0000 (19:02 -0400)
src/time/strftime.c

index 3f0ec3e..87e87d5 100644 (file)
@@ -44,168 +44,178 @@ static int week_num(const struct tm *tm)
        return val;
 }
 
-size_t __strftime_l(char *restrict s, size_t n, const char *restrict f, const struct tm *restrict tm, locale_t loc)
+size_t __strftime_l(char *restrict, size_t, const char *restrict, const struct tm *restrict, locale_t);
+
+int __strftime_fmt_1(char *s, size_t n, int f, const struct tm *tm, locale_t loc)
 {
        nl_item item;
        int val;
        const char *fmt;
        size_t l;
-       for (l=0; *f && l<n; f++) {
-               if (*f != '%') {
-literal:
-                       s[l++] = *f;
-                       continue;
-               }
-do_fmt:
-               switch (*++f) {
-               case '%':
-                       goto literal;
-               case 'E':
-               case 'O':
-                       goto do_fmt;
-               case 'a':
-                       item = ABDAY_1 + tm->tm_wday;
-                       goto nl_strcat;
-               case 'A':
-                       item = DAY_1 + tm->tm_wday;
-                       goto nl_strcat;
-               case 'h':
-               case 'b':
-                       item = ABMON_1 + tm->tm_mon;
-                       goto nl_strcat;
-               case 'B':
-                       item = MON_1 + tm->tm_mon;
-                       goto nl_strcat;
-               case 'c':
-                       item = D_T_FMT;
-                       goto nl_strftime;
-               case 'C':
-                       val = (1900+tm->tm_year) / 100;
-                       fmt = "%02d";
-                       goto number;
-               case 'd':
-                       val = tm->tm_mday;
-                       fmt = "%02d";
-                       goto number;
-               case 'D':
-                       fmt = "%m/%d/%y";
-                       goto recu_strftime;
-               case 'e':
-                       val = tm->tm_mday;
-                       fmt = "%2d";
-                       goto number;
-               case 'F':
-                       fmt = "%Y-%m-%d";
-                       goto recu_strftime;
-               case 'g':
-               case 'G':
-                       fmt = "%04d";
-                       val = tm->tm_year + 1900;
-                       if (tm->tm_yday < 3 && week_num(tm) != 1) val--;
-                       else if (tm->tm_yday > 360 && week_num(tm) == 1) val++;
-                       if (*f=='g') {
-                               fmt = "%02d";
-                               val %= 100;
-                       }
-                       goto number;
-               case 'H':
-                       val = tm->tm_hour;
-                       fmt = "%02d";
-                       goto number;
-               case 'I':
-                       val = tm->tm_hour;
-                       if (!val) val = 12;
-                       else if (val > 12) val -= 12;
-                       fmt = "%02d";
-                       goto number;
-               case 'j':
-                       val = tm->tm_yday+1;
-                       fmt = "%03d";
-                       goto number;
-               case 'm':
-                       val = tm->tm_mon+1;
-                       fmt = "%02d";
-                       goto number;
-               case 'M':
-                       val = tm->tm_min;
-                       fmt = "%02d";
-                       goto number;
-               case 'n':
-                       s[l++] = '\n';
-                       continue;
-               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->tm_sec;
-                       fmt = "%02d";
-                       goto number;
-               case 't':
-                       s[l++] = '\t';
-                       continue;
-               case 'T':
-                       fmt = "%H:%M:%S";
-                       goto recu_strftime;
-               case 'u':
-                       val = tm->tm_wday ? tm->tm_wday : 7;
-                       fmt = "%d";
-                       goto number;
-               case 'U':
-                       val = (tm->tm_yday + 7 - tm->tm_wday) / 7;
-                       fmt = "%02d";
-                       goto number;
-               case 'W':
-                       val = (tm->tm_yday + 7 - (tm->tm_wday+6)%7) / 7;
-                       fmt = "%02d";
-                       goto number;
-               case 'V':
-                       val = week_num(tm);
-                       fmt = "%02d";
-                       goto number;
-               case 'w':
-                       val = tm->tm_wday;
-                       fmt = "%d";
-                       goto number;
-               case 'x':
-                       item = D_FMT;
-                       goto nl_strftime;
-               case 'X':
-                       item = T_FMT;
-                       goto nl_strftime;
-               case 'y':
-                       val = tm->tm_year % 100;
+
+       if (n<2) return 0;
+
+       switch (f) {
+       case 'a':
+               item = ABDAY_1 + tm->tm_wday;
+               goto nl_strcat;
+       case 'A':
+               item = DAY_1 + tm->tm_wday;
+               goto nl_strcat;
+       case 'h':
+       case 'b':
+               item = ABMON_1 + tm->tm_mon;
+               goto nl_strcat;
+       case 'B':
+               item = MON_1 + tm->tm_mon;
+               goto nl_strcat;
+       case 'c':
+               item = D_T_FMT;
+               goto nl_strftime;
+       case 'C':
+               val = (1900+tm->tm_year) / 100;
+               fmt = "%02d";
+               goto number;
+       case 'd':
+               val = tm->tm_mday;
+               fmt = "%02d";
+               goto number;
+       case 'D':
+               fmt = "%m/%d/%y";
+               goto recu_strftime;
+       case 'e':
+               val = tm->tm_mday;
+               fmt = "%2d";
+               goto number;
+       case 'F':
+               fmt = "%Y-%m-%d";
+               goto recu_strftime;
+       case 'g':
+       case 'G':
+               fmt = "%04d";
+               val = tm->tm_year + 1900;
+               if (tm->tm_yday < 3 && week_num(tm) != 1) val--;
+               else if (tm->tm_yday > 360 && week_num(tm) == 1) val++;
+               if (f=='g') {
                        fmt = "%02d";
-                       goto number;
-               case 'Y':
-                       val = tm->tm_year + 1900;
-                       fmt = "%04d";
-                       goto number;
-               case 'z':
-                       val = -tm->__tm_gmtoff;
-                       l += snprintf(s+l, n-l, "%+.2d%.2d", val/3600, abs(val%3600)/60);
-                       continue;
-               case 'Z':
-                       l += snprintf(s+l, n-l, "%s", tm->__tm_zone);
-                       continue;
-               default:
-                       return 0;
+                       val %= 100;
                }
+               goto number;
+       case 'H':
+               val = tm->tm_hour;
+               fmt = "%02d";
+               goto number;
+       case 'I':
+               val = tm->tm_hour;
+               if (!val) val = 12;
+               else if (val > 12) val -= 12;
+               fmt = "%02d";
+               goto number;
+       case 'j':
+               val = tm->tm_yday+1;
+               fmt = "%03d";
+               goto number;
+       case 'm':
+               val = tm->tm_mon+1;
+               fmt = "%02d";
+               goto number;
+       case 'M':
+               val = tm->tm_min;
+               fmt = "%02d";
+               goto number;
+       case 'n':
+               s[0] = '\n';
+               s[1] = 0;
+               return 1;
+       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->tm_sec;
+               fmt = "%02d";
+               goto number;
+       case 't':
+               s[0] = '\t';
+               s[1] = 0;
+               return 1;
+       case 'T':
+               fmt = "%H:%M:%S";
+               goto recu_strftime;
+       case 'u':
+               val = tm->tm_wday ? tm->tm_wday : 7;
+               fmt = "%d";
+               goto number;
+       case 'U':
+               val = (tm->tm_yday + 7 - tm->tm_wday) / 7;
+               fmt = "%02d";
+               goto number;
+       case 'W':
+               val = (tm->tm_yday + 7 - (tm->tm_wday+6)%7) / 7;
+               fmt = "%02d";
+               goto number;
+       case 'V':
+               val = week_num(tm);
+               fmt = "%02d";
+               goto number;
+       case 'w':
+               val = tm->tm_wday;
+               fmt = "%d";
+               goto number;
+       case 'x':
+               item = D_FMT;
+               goto nl_strftime;
+       case 'X':
+               item = T_FMT;
+               goto nl_strftime;
+       case 'y':
+               val = tm->tm_year % 100;
+               fmt = "%02d";
+               goto number;
+       case 'Y':
+               val = tm->tm_year + 1900;
+               fmt = "%04d";
+               goto number;
+       case 'z':
+               val = -tm->__tm_gmtoff;
+               return snprintf(s, n, "%+.2d%.2d", val/3600, abs(val%3600)/60);
+       case 'Z':
+               return snprintf(s, n, "%s", tm->__tm_zone);
+       case '%':
+               s[0] = '%';
+               s[1] = 0;
+               return 1;
+       default:
+               return 0;
+       }
 number:
-               l += snprintf(s+l, n-l, fmt, val);
-               continue;
+       return snprintf(s, n, fmt, val);
 nl_strcat:
-               l += snprintf(s+l, n-l, "%s", __nl_langinfo_l(item, loc));
-               continue;
+       return snprintf(s, n, "%s", __nl_langinfo_l(item, loc));
 nl_strftime:
-               fmt = __nl_langinfo_l(item, loc);
+       fmt = __nl_langinfo_l(item, loc);
 recu_strftime:
-               l += __strftime_l(s+l, n-l, fmt, tm, loc);
+       return __strftime_l(s, n, fmt, tm, loc);
+}
+
+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;
+       for (l=0; *f && l<n; f++) {
+               if (*f != '%') {
+                       s[l++] = *f;
+                       continue;
+               }
+               f++;
+               if (*f == 'E' || *f == 'O') f++;
+               k = __strftime_fmt_1(s+l, n-l, *f, tm, loc);
+               if (!k) return 0;
+               l += k;
        }
        if (l >= n) return 0;
        s[l] = 0;