strftime.c revision a48fa7f4deb6ba703e1da55143771476d4e668ce 
1#ifndef lint
2#ifndef NOID
3static char elsieid[] = "@(#)strftime.c 8.1";
4/*
5** Based on the UCB version with the ID appearing below.
6** This is ANSIish only when "multibyte character == plain character".
7*/
8#endif /* !defined NOID */
9#endif /* !defined lint */
10
11#include "private.h"
12
13/*
14** Copyright (c) 1989 The Regents of the University of California.
15** All rights reserved.
16**
17** Redistribution and use in source and binary forms are permitted
18** provided that the above copyright notice and this paragraph are
19** duplicated in all such forms and that any documentation,
20** advertising materials, and other materials related to such
21** distribution and use acknowledge that the software was developed
22** by the University of California, Berkeley. The name of the
23** University may not be used to endorse or promote products derived
24** from this software without specific prior written permission.
25** THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
26** IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
27** WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
28*/
29
30#ifndef LIBC_SCCS
31#ifndef lint
32static const char   sccsid[] = "@(#)strftime.c  5.4 (Berkeley) 3/14/89";
33#endif /* !defined lint */
34#endif /* !defined LIBC_SCCS */
35
36#include "tzfile.h"
37#include "fcntl.h"
38#include "locale.h"
39#include <ctype.h>
40#include <time64.h>
41
42/* struct lc_time_T is now defined as strftime_locale
43 * in <time.h>
44 */
45#if 1
46#define  lc_time_T    strftime_locale
47#else
48struct lc_time_T {
49    const char *    mon[MONSPERYEAR];
50    const char *    month[MONSPERYEAR];
51    const char *    wday[DAYSPERWEEK];
52    const char *    weekday[DAYSPERWEEK];
53    const char *    X_fmt;
54    const char *    x_fmt;
55    const char *    c_fmt;
56    const char *    am;
57    const char *    pm;
58    const char *    date_fmt;
59};
60#endif
61
62#define Locale  (&C_time_locale)
63
64static const struct lc_time_T   C_time_locale = {
65    {
66        "Jan", "Feb", "Mar", "Apr", "May", "Jun",
67        "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
68    }, {
69        "January", "February", "March", "April", "May", "June",
70        "July", "August", "September", "October", "November", "December"
71    }, {
72        "January", "February", "March", "April", "May", "June",
73        "July", "August", "September", "October", "November", "December"
74    }, {
75        "Sun", "Mon", "Tue", "Wed",
76        "Thu", "Fri", "Sat"
77    }, {
78        "Sunday", "Monday", "Tuesday", "Wednesday",
79        "Thursday", "Friday", "Saturday"
80    },
81
82    /* X_fmt */
83    "%H:%M:%S",
84
85    /*
86    ** x_fmt
87    ** C99 requires this format.
88    ** Using just numbers (as here) makes Quakers happier;
89    ** it's also compatible with SVR4.
90    */
91    "%m/%d/%y",
92
93    /*
94    ** c_fmt
95    ** C99 requires this format.
96    ** Previously this code used "%D %X", but we now conform to C99.
97    ** Note that
98    **  "%a %b %d %H:%M:%S %Y"
99    ** is used by Solaris 2.3.
100    */
101    "%a %b %e %T %Y",
102
103    /* am */
104    "AM",
105
106    /* pm */
107    "PM",
108
109    /* date_fmt */
110    "%a %b %e %H:%M:%S %Z %Y"
111};
112
113static char *   _add P((const char *, char *, const char *, int));
114static char *   _conv P((int, const char *, char *, const char *));
115static char *   _fmt P((const char *, const struct tm *, char *, const char *,
116            int *, const struct strftime_locale*));
117static char *   _yconv P((int, int, int, int, char *, const char *, int));
118static char *   getformat P((int, char *, char *, char *, char *));
119
120extern char *   tzname[];
121
122#ifndef YEAR_2000_NAME
123#define YEAR_2000_NAME  "CHECK_STRFTIME_FORMATS_FOR_TWO_DIGIT_YEARS"
124#endif /* !defined YEAR_2000_NAME */
125
126#define IN_NONE 0
127#define IN_SOME 1
128#define IN_THIS 2
129#define IN_ALL  3
130
131#define FORCE_LOWER_CASE 0x100
132
133size_t
134strftime(s, maxsize, format, t)
135char * const        s;
136const size_t        maxsize;
137const char * const  format;
138const struct tm * const t;
139{
140    return strftime_tz(s, maxsize, format, t, Locale);
141}
142
143size_t
144strftime_tz(s, maxsize, format, t, locale)
145char * const        s;
146const size_t        maxsize;
147const char * const  format;
148const struct tm * const t;
149const struct strftime_locale *locale;
150{
151    char *  p;
152    int warn;
153
154    tzset();
155    warn = IN_NONE;
156    p = _fmt(((format == NULL) ? "%c" : format), t, s, s + maxsize, &warn, locale);
157#if 0  /* ifndef NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU */
158    if (warn != IN_NONE && getenv(YEAR_2000_NAME) != NULL) {
159        (void) fprintf(stderr, "\n");
160        if (format == NULL)
161            (void) fprintf(stderr, "NULL strftime format ");
162        else    (void) fprintf(stderr, "strftime format \"%s\" ",
163                format);
164        (void) fprintf(stderr, "yields only two digits of years in ");
165        if (warn == IN_SOME)
166            (void) fprintf(stderr, "some locales");
167        else if (warn == IN_THIS)
168            (void) fprintf(stderr, "the current locale");
169        else    (void) fprintf(stderr, "all locales");
170        (void) fprintf(stderr, "\n");
171    }
172#endif /* !defined NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU */
173    if (p == s + maxsize)
174        return 0;
175    *p = '\0';
176    return p - s;
177}
178
179static char *getformat(int modifier, char *normal, char *underscore,
180                       char *dash, char *zero) {
181    switch (modifier) {
182    case '_':
183        return underscore;
184
185    case '-':
186        return dash;
187
188    case '0':
189        return zero;
190    }
191
192    return normal;
193}
194
195static char *
196_fmt(format, t, pt, ptlim, warnp, locale)
197const char *        format;
198const struct tm * const t;
199char *          pt;
200const char * const  ptlim;
201int *           warnp;
202const struct strftime_locale* locale;
203{
204    for ( ; *format; ++format) {
205        if (*format == '%') {
206            int modifier = 0;
207label:
208            switch (*++format) {
209            case '\0':
210                --format;
211                break;
212            case 'A':
213                pt = _add((t->tm_wday < 0 ||
214                    t->tm_wday >= DAYSPERWEEK) ?
215                    "?" : locale->weekday[t->tm_wday],
216                    pt, ptlim, modifier);
217                continue;
218            case 'a':
219                pt = _add((t->tm_wday < 0 ||
220                    t->tm_wday >= DAYSPERWEEK) ?
221                    "?" : locale->wday[t->tm_wday],
222                    pt, ptlim, modifier);
223                continue;
224            case 'B':
225                if (modifier == '-') {
226                    pt = _add((t->tm_mon < 0 ||
227                                t->tm_mon >= MONSPERYEAR) ?
228                                "?" : Locale->standalone_month[t->tm_mon],
229                                pt, ptlim, modifier);
230                } else {
231                    pt = _add((t->tm_mon < 0 ||
232                                t->tm_mon >= MONSPERYEAR) ?
233                                "?" : Locale->month[t->tm_mon],
234                                pt, ptlim, modifier);
235                }
236                continue;
237            case 'b':
238            case 'h':
239                pt = _add((t->tm_mon < 0 ||
240                    t->tm_mon >= MONSPERYEAR) ?
241                    "?" : locale->mon[t->tm_mon],
242                    pt, ptlim, modifier);
243                continue;
244            case 'C':
245                /*
246                ** %C used to do a...
247                **  _fmt("%a %b %e %X %Y", t);
248                ** ...whereas now POSIX 1003.2 calls for
249                ** something completely different.
250                ** (ado, 1993-05-24)
251                */
252                pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 0,
253                    pt, ptlim, modifier);
254                continue;
255            case 'c':
256                {
257                int warn2 = IN_SOME;
258
259                pt = _fmt(locale->c_fmt, t, pt, ptlim, warnp, locale);
260                if (warn2 == IN_ALL)
261                    warn2 = IN_THIS;
262                if (warn2 > *warnp)
263                    *warnp = warn2;
264                }
265                continue;
266            case 'D':
267                                pt = _fmt("%m/%d/%y", t, pt, ptlim, warnp, locale);
268                continue;
269            case 'd':
270                                pt = _conv(t->tm_mday,
271                                           getformat(modifier, "%02d",
272                                                     "%2d", "%d", "%02d"),
273                                           pt, ptlim);
274                continue;
275            case 'E':
276            case 'O':
277                /*
278                ** C99 locale modifiers.
279                ** The sequences
280                **  %Ec %EC %Ex %EX %Ey %EY
281                **  %Od %oe %OH %OI %Om %OM
282                **  %OS %Ou %OU %OV %Ow %OW %Oy
283                ** are supposed to provide alternate
284                ** representations.
285                */
286                goto label;
287            case '_':
288            case '-':
289            case '0':
290            case '^':
291            case '#':
292                modifier = *format;
293                goto label;
294            case 'e':
295                pt = _conv(t->tm_mday,
296                                           getformat(modifier, "%2d",
297                                                     "%2d", "%d", "%02d"),
298                                           pt, ptlim);
299                continue;
300            case 'F':
301                pt = _fmt("%Y-%m-%d", t, pt, ptlim, warnp, locale);
302                continue;
303            case 'H':
304                pt = _conv(t->tm_hour,
305                                           getformat(modifier, "%02d",
306                                                     "%2d", "%d", "%02d"),
307                                           pt, ptlim);
308                continue;
309            case 'I':
310                pt = _conv((t->tm_hour % 12) ?
311                    (t->tm_hour % 12) : 12,
312                    getformat(modifier, "%02d",
313                                                  "%2d", "%d", "%02d"),
314                                        pt, ptlim);
315                continue;
316            case 'j':
317                pt = _conv(t->tm_yday + 1,
318                           getformat(modifier, "%03d", "%3d", "%d", "%03d"),
319                           pt, ptlim);
320                continue;
321            case 'k':
322                /*
323                ** This used to be...
324                **  _conv(t->tm_hour % 12 ?
325                **      t->tm_hour % 12 : 12, 2, ' ');
326                ** ...and has been changed to the below to
327                ** match SunOS 4.1.1 and Arnold Robbins'
328                ** strftime version 3.0. That is, "%k" and
329                ** "%l" have been swapped.
330                ** (ado, 1993-05-24)
331                */
332                pt = _conv(t->tm_hour,
333                                           getformat(modifier, "%2d",
334                                                     "%2d", "%d", "%02d"),
335                                           pt, ptlim);
336                continue;
337#ifdef KITCHEN_SINK
338            case 'K':
339                /*
340                ** After all this time, still unclaimed!
341                */
342                pt = _add("kitchen sink", pt, ptlim, modifier);
343                continue;
344#endif /* defined KITCHEN_SINK */
345            case 'l':
346                /*
347                ** This used to be...
348                **  _conv(t->tm_hour, 2, ' ');
349                ** ...and has been changed to the below to
350                ** match SunOS 4.1.1 and Arnold Robbin's
351                ** strftime version 3.0. That is, "%k" and
352                ** "%l" have been swapped.
353                ** (ado, 1993-05-24)
354                */
355                pt = _conv((t->tm_hour % 12) ?
356                    (t->tm_hour % 12) : 12,
357                    getformat(modifier, "%2d",
358                                                  "%2d", "%d", "%02d"),
359                                        pt, ptlim);
360                continue;
361            case 'M':
362                pt = _conv(t->tm_min,
363                                           getformat(modifier, "%02d",
364                                                     "%2d", "%d", "%02d"),
365                                           pt, ptlim);
366                continue;
367            case 'm':
368                pt = _conv(t->tm_mon + 1,
369                                           getformat(modifier, "%02d",
370                                                     "%2d", "%d", "%02d"),
371                                           pt, ptlim);
372                continue;
373            case 'n':
374                pt = _add("\n", pt, ptlim, modifier);
375                continue;
376            case 'p':
377                pt = _add((t->tm_hour >= (HOURSPERDAY / 2)) ?
378                    locale->pm :
379                    locale->am,
380                    pt, ptlim, modifier);
381                continue;
382            case 'P':
383                pt = _add((t->tm_hour >= (HOURSPERDAY / 2)) ?
384                    locale->pm :
385                    locale->am,
386                    pt, ptlim, FORCE_LOWER_CASE);
387                continue;
388            case 'R':
389                pt = _fmt("%H:%M", t, pt, ptlim, warnp, locale);
390                continue;
391            case 'r':
392                pt = _fmt("%I:%M:%S %p", t, pt, ptlim, warnp, locale);
393                continue;
394            case 'S':
395                pt = _conv(t->tm_sec,
396                                           getformat(modifier, "%02d",
397                                                     "%2d", "%d", "%02d"),
398                                           pt, ptlim);
399                continue;
400            case 's':
401                {
402                    struct tm   tm;
403                    char        buf[INT_STRLEN_MAXIMUM(
404                                time64_t) + 1];
405                    time64_t    mkt;
406
407                    tm = *t;
408                    mkt = mktime64(&tm);
409                    if (TYPE_SIGNED(time64_t))
410                        (void) sprintf(buf, "%lld",
411                            (long long) mkt);
412                    else    (void) sprintf(buf, "%llu",
413                            (unsigned long long) mkt);
414                    pt = _add(buf, pt, ptlim, modifier);
415                }
416                continue;
417            case 'T':
418                pt = _fmt("%H:%M:%S", t, pt, ptlim, warnp, locale);
419                continue;
420            case 't':
421                pt = _add("\t", pt, ptlim, modifier);
422                continue;
423            case 'U':
424                pt = _conv((t->tm_yday + DAYSPERWEEK -
425                    t->tm_wday) / DAYSPERWEEK,
426                    getformat(modifier, "%02d",
427                                                  "%2d", "%d", "%02d"),
428                                        pt, ptlim);
429                continue;
430            case 'u':
431                /*
432                ** From Arnold Robbins' strftime version 3.0:
433                ** "ISO 8601: Weekday as a decimal number
434                ** [1 (Monday) - 7]"
435                ** (ado, 1993-05-24)
436                */
437                pt = _conv((t->tm_wday == 0) ?
438                    DAYSPERWEEK : t->tm_wday, "%d", pt, ptlim);
439                continue;
440            case 'V':   /* ISO 8601 week number */
441            case 'G':   /* ISO 8601 year (four digits) */
442            case 'g':   /* ISO 8601 year (two digits) */
443/*
444** From Arnold Robbins' strftime version 3.0: "the week number of the
445** year (the first Monday as the first day of week 1) as a decimal number
446** (01-53)."
447** (ado, 1993-05-24)
448**
449** From "http://www.ft.uni-erlangen.de/~mskuhn/iso-time.html" by Markus Kuhn:
450** "Week 01 of a year is per definition the first week which has the
451** Thursday in this year, which is equivalent to the week which contains
452** the fourth day of January. In other words, the first week of a new year
453** is the week which has the majority of its days in the new year. Week 01
454** might also contain days from the previous year and the week before week
455** 01 of a year is the last week (52 or 53) of the previous year even if
456** it contains days from the new year. A week starts with Monday (day 1)
457** and ends with Sunday (day 7). For example, the first week of the year
458** 1997 lasts from 1996-12-30 to 1997-01-05..."
459** (ado, 1996-01-02)
460*/
461                {
462                    int year;
463                    int base;
464                    int yday;
465                    int wday;
466                    int w;
467
468                    year = t->tm_year;
469                    base = TM_YEAR_BASE;
470                    yday = t->tm_yday;
471                    wday = t->tm_wday;
472                    for ( ; ; ) {
473                        int len;
474                        int bot;
475                        int top;
476
477                        len = isleap_sum(year, base) ?
478                            DAYSPERLYEAR :
479                            DAYSPERNYEAR;
480                        /*
481                        ** What yday (-3 ... 3) does
482                        ** the ISO year begin on?
483                        */
484                        bot = ((yday + 11 - wday) %
485                            DAYSPERWEEK) - 3;
486                        /*
487                        ** What yday does the NEXT
488                        ** ISO year begin on?
489                        */
490                        top = bot -
491                            (len % DAYSPERWEEK);
492                        if (top < -3)
493                            top += DAYSPERWEEK;
494                        top += len;
495                        if (yday >= top) {
496                            ++base;
497                            w = 1;
498                            break;
499                        }
500                        if (yday >= bot) {
501                            w = 1 + ((yday - bot) /
502                                DAYSPERWEEK);
503                            break;
504                        }
505                        --base;
506                        yday += isleap_sum(year, base) ?
507                            DAYSPERLYEAR :
508                            DAYSPERNYEAR;
509                    }
510#ifdef XPG4_1994_04_09
511                    if ((w == 52 &&
512                        t->tm_mon == TM_JANUARY) ||
513                        (w == 1 &&
514                        t->tm_mon == TM_DECEMBER))
515                            w = 53;
516#endif /* defined XPG4_1994_04_09 */
517                    if (*format == 'V')
518                        pt = _conv(w,
519                                                           getformat(modifier,
520                                                                     "%02d",
521                                                                     "%2d",
522                                                                     "%d",
523                                                                     "%02d"),
524                               pt, ptlim);
525                    else if (*format == 'g') {
526                        *warnp = IN_ALL;
527                        pt = _yconv(year, base, 0, 1,
528                            pt, ptlim, modifier);
529                    } else  pt = _yconv(year, base, 1, 1,
530                            pt, ptlim, modifier);
531                }
532                continue;
533            case 'v':
534                /*
535                ** From Arnold Robbins' strftime version 3.0:
536                ** "date as dd-bbb-YYYY"
537                ** (ado, 1993-05-24)
538                */
539                pt = _fmt("%e-%b-%Y", t, pt, ptlim, warnp, locale);
540                continue;
541            case 'W':
542                pt = _conv((t->tm_yday + DAYSPERWEEK -
543                    (t->tm_wday ?
544                    (t->tm_wday - 1) :
545                    (DAYSPERWEEK - 1))) / DAYSPERWEEK,
546                    getformat(modifier, "%02d",
547                                                  "%2d", "%d", "%02d"),
548                                        pt, ptlim);
549                continue;
550            case 'w':
551                pt = _conv(t->tm_wday, "%d", pt, ptlim);
552                continue;
553            case 'X':
554                pt = _fmt(locale->X_fmt, t, pt, ptlim, warnp, locale);
555                continue;
556            case 'x':
557                {
558                int warn2 = IN_SOME;
559
560                pt = _fmt(locale->x_fmt, t, pt, ptlim, &warn2, locale);
561                if (warn2 == IN_ALL)
562                    warn2 = IN_THIS;
563                if (warn2 > *warnp)
564                    *warnp = warn2;
565                }
566                continue;
567            case 'y':
568                *warnp = IN_ALL;
569                pt = _yconv(t->tm_year, TM_YEAR_BASE, 0, 1,
570                    pt, ptlim, modifier);
571                continue;
572            case 'Y':
573                pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 1,
574                    pt, ptlim, modifier);
575                continue;
576            case 'Z':
577#ifdef TM_ZONE
578                if (t->TM_ZONE != NULL)
579                    pt = _add(t->TM_ZONE, pt, ptlim,
580                                                  modifier);
581                else
582#endif /* defined TM_ZONE */
583                if (t->tm_isdst >= 0)
584                    pt = _add(tzname[t->tm_isdst != 0],
585                        pt, ptlim, modifier);
586                /*
587                ** C99 says that %Z must be replaced by the
588                ** empty string if the time zone is not
589                ** determinable.
590                */
591                continue;
592            case 'z':
593                {
594                int     diff;
595                char const *    sign;
596
597                if (t->tm_isdst < 0)
598                    continue;
599#ifdef TM_GMTOFF
600                diff = t->TM_GMTOFF;
601#else /* !defined TM_GMTOFF */
602                /*
603                ** C99 says that the UTC offset must
604                ** be computed by looking only at
605                ** tm_isdst. This requirement is
606                ** incorrect, since it means the code
607                ** must rely on magic (in this case
608                ** altzone and timezone), and the
609                ** magic might not have the correct
610                ** offset. Doing things correctly is
611                ** tricky and requires disobeying C99;
612                ** see GNU C strftime for details.
613                ** For now, punt and conform to the
614                ** standard, even though it's incorrect.
615                **
616                ** C99 says that %z must be replaced by the
617                ** empty string if the time zone is not
618                ** determinable, so output nothing if the
619                ** appropriate variables are not available.
620                */
621                if (t->tm_isdst == 0)
622#ifdef USG_COMPAT
623                    diff = -timezone;
624#else /* !defined USG_COMPAT */
625                    continue;
626#endif /* !defined USG_COMPAT */
627                else
628#ifdef ALTZONE
629                    diff = -altzone;
630#else /* !defined ALTZONE */
631                    continue;
632#endif /* !defined ALTZONE */
633#endif /* !defined TM_GMTOFF */
634                if (diff < 0) {
635                    sign = "-";
636                    diff = -diff;
637                } else  sign = "+";
638                pt = _add(sign, pt, ptlim, modifier);
639                diff /= SECSPERMIN;
640                diff = (diff / MINSPERHOUR) * 100 +
641                    (diff % MINSPERHOUR);
642                pt = _conv(diff,
643                                           getformat(modifier, "%04d",
644                                                     "%4d", "%d", "%04d"),
645                                           pt, ptlim);
646                }
647                continue;
648            case '+':
649                pt = _fmt(locale->date_fmt, t, pt, ptlim,
650                    warnp, locale);
651                continue;
652            case '%':
653            /*
654            ** X311J/88-090 (4.12.3.5): if conversion char is
655            ** undefined, behavior is undefined. Print out the
656            ** character itself as printf(3) also does.
657            */
658            default:
659                break;
660            }
661        }
662        if (pt == ptlim)
663            break;
664        *pt++ = *format;
665    }
666    return pt;
667}
668
669static char *
670_conv(n, format, pt, ptlim)
671const int       n;
672const char * const  format;
673char * const        pt;
674const char * const  ptlim;
675{
676    char    buf[INT_STRLEN_MAXIMUM(int) + 1];
677
678    (void) snprintf(buf, sizeof(buf), format, n);
679    return _add(buf, pt, ptlim, 0);
680}
681
682static char *
683_add(str, pt, ptlim, modifier)
684const char *        str;
685char *          pt;
686const char * const  ptlim;
687int                     modifier;
688{
689        int c;
690
691        switch (modifier) {
692        case FORCE_LOWER_CASE:
693                while (pt < ptlim && (*pt = tolower(*str++)) != '\0') {
694                        ++pt;
695                }
696                break;
697
698        case '^':
699                while (pt < ptlim && (*pt = toupper(*str++)) != '\0') {
700                        ++pt;
701                }
702                break;
703
704        case '#':
705                while (pt < ptlim && (c = *str++) != '\0') {
706                        if (isupper(c)) {
707                                c = tolower(c);
708                        } else if (islower(c)) {
709                                c = toupper(c);
710                        }
711                        *pt = c;
712                        ++pt;
713                }
714
715                break;
716
717        default:
718                while (pt < ptlim && (*pt = *str++) != '\0') {
719                        ++pt;
720                }
721        }
722
723    return pt;
724}
725
726/*
727** POSIX and the C Standard are unclear or inconsistent about
728** what %C and %y do if the year is negative or exceeds 9999.
729** Use the convention that %C concatenated with %y yields the
730** same output as %Y, and that %Y contains at least 4 bytes,
731** with more only if necessary.
732*/
733
734static char *
735_yconv(a, b, convert_top, convert_yy, pt, ptlim, modifier)
736const int       a;
737const int       b;
738const int       convert_top;
739const int       convert_yy;
740char *          pt;
741const char * const  ptlim;
742int                     modifier;
743{
744    register int    lead;
745    register int    trail;
746
747#define DIVISOR 100
748    trail = a % DIVISOR + b % DIVISOR;
749    lead = a / DIVISOR + b / DIVISOR + trail / DIVISOR;
750    trail %= DIVISOR;
751    if (trail < 0 && lead > 0) {
752        trail += DIVISOR;
753        --lead;
754    } else if (lead < 0 && trail > 0) {
755        trail -= DIVISOR;
756        ++lead;
757    }
758    if (convert_top) {
759        if (lead == 0 && trail < 0)
760            pt = _add("-0", pt, ptlim, modifier);
761        else    pt = _conv(lead, getformat(modifier, "%02d",
762                                                   "%2d", "%d", "%02d"),
763                                   pt, ptlim);
764    }
765    if (convert_yy)
766        pt = _conv(((trail < 0) ? -trail : trail),
767                           getformat(modifier, "%02d", "%2d", "%d", "%02d"),
768                           pt, ptlim);
769    return pt;
770}
771