1 /*
2 ** This file is in the public domain, so clarified as of
3 ** 1996-06-05 by Arthur David Olson.
4 */
5 
6 /*
7 ** Leap second handling from Bradley White.
8 ** POSIX-style TZ environment variable handling from Guy Harris.
9 */
10 
11 /*LINTLIBRARY*/
12 
13 #include "private.h"
14 #include "tzfile.h"
15 #include "fcntl.h"
16 
17 #ifndef TZ_ABBR_MAX_LEN
18 #define TZ_ABBR_MAX_LEN 16
19 #endif /* !defined TZ_ABBR_MAX_LEN */
20 
21 #ifndef TZ_ABBR_CHAR_SET
22 #define TZ_ABBR_CHAR_SET \
23     "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 :+-._"
24 #endif /* !defined TZ_ABBR_CHAR_SET */
25 
26 #ifndef TZ_ABBR_ERR_CHAR
27 #define TZ_ABBR_ERR_CHAR    '_'
28 #endif /* !defined TZ_ABBR_ERR_CHAR */
29 
30 /*
31 ** SunOS 4.1.1 headers lack O_BINARY.
32 */
33 
34 #ifdef O_BINARY
35 #define OPEN_MODE   (O_RDONLY | O_BINARY)
36 #endif /* defined O_BINARY */
37 #ifndef O_BINARY
38 #define OPEN_MODE   O_RDONLY
39 #endif /* !defined O_BINARY */
40 
41 #if 0
42 #  define  XLOG(xx)  printf xx , fflush(stdout)
43 #else
44 #  define  XLOG(x)   do{}while (0)
45 #endif
46 
47 /* BEGIN android-added: thread-safety. */
48 #include <pthread.h>
49 static pthread_mutex_t _tzMutex = PTHREAD_MUTEX_INITIALIZER;
_tzLock(void)50 static inline void _tzLock(void) { pthread_mutex_lock(&_tzMutex); }
_tzUnlock(void)51 static inline void _tzUnlock(void) { pthread_mutex_unlock(&_tzMutex); }
52 /* END android-added */
53 
54 #ifndef WILDABBR
55 /*
56 ** Someone might make incorrect use of a time zone abbreviation:
57 **  1.  They might reference tzname[0] before calling tzset (explicitly
58 **      or implicitly).
59 **  2.  They might reference tzname[1] before calling tzset (explicitly
60 **      or implicitly).
61 **  3.  They might reference tzname[1] after setting to a time zone
62 **      in which Daylight Saving Time is never observed.
63 **  4.  They might reference tzname[0] after setting to a time zone
64 **      in which Standard Time is never observed.
65 **  5.  They might reference tm.TM_ZONE after calling offtime.
66 ** What's best to do in the above cases is open to debate;
67 ** for now, we just set things up so that in any of the five cases
68 ** WILDABBR is used. Another possibility: initialize tzname[0] to the
69 ** string "tzname[0] used before set", and similarly for the other cases.
70 ** And another: initialize tzname[0] to "ERA", with an explanation in the
71 ** manual page of what this "time zone abbreviation" means (doing this so
72 ** that tzname[0] has the "normal" length of three characters).
73 */
74 #define WILDABBR    "   "
75 #endif /* !defined WILDABBR */
76 
77 static const char       wildabbr[] = WILDABBR;
78 
79 static const char gmt[] = "GMT";
80 
81 /*
82 ** The DST rules to use if TZ has no rules and we can't load TZDEFRULES.
83 ** We default to US rules as of 1999-08-17.
84 ** POSIX 1003.1 section 8.1.1 says that the default DST rules are
85 ** implementation dependent; for historical reasons, US rules are a
86 ** common default.
87 */
88 #ifndef TZDEFRULESTRING
89 #define TZDEFRULESTRING ",M4.1.0,M10.5.0"
90 #endif /* !defined TZDEFDST */
91 
92 struct ttinfo {              /* time type information */
93     int_fast32_t tt_gmtoff;  /* UT offset in seconds */
94     int          tt_isdst;   /* used to set tm_isdst */
95     int          tt_abbrind; /* abbreviation list index */
96     int          tt_ttisstd; /* TRUE if transition is std time */
97     int          tt_ttisgmt; /* TRUE if transition is UT */
98 };
99 
100 struct lsinfo {              /* leap second information */
101     time_t       ls_trans;   /* transition time */
102     int_fast64_t ls_corr;    /* correction to apply */
103 };
104 
105 #define BIGGEST(a, b)   (((a) > (b)) ? (a) : (b))
106 
107 #ifdef TZNAME_MAX
108 #define MY_TZNAME_MAX   TZNAME_MAX
109 #endif /* defined TZNAME_MAX */
110 #ifndef TZNAME_MAX
111 #define MY_TZNAME_MAX   255
112 #endif /* !defined TZNAME_MAX */
113 
114 struct state {
115     int           leapcnt;
116     int           timecnt;
117     int           typecnt;
118     int           charcnt;
119     int           goback;
120     int           goahead;
121     time_t        ats[TZ_MAX_TIMES];
122     unsigned char types[TZ_MAX_TIMES];
123     struct ttinfo ttis[TZ_MAX_TYPES];
124     char          chars[BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt),
125                   (2 * (MY_TZNAME_MAX + 1)))];
126     struct lsinfo lsis[TZ_MAX_LEAPS];
127     int           defaulttype; /* for early times or if no transitions */
128 };
129 
130 struct rule {
131     int          r_type; /* type of rule; see below */
132     int          r_day;  /* day number of rule */
133     int          r_week; /* week number of rule */
134     int          r_mon;  /* month number of rule */
135     int_fast32_t r_time; /* transition time of rule */
136 };
137 
138 #define JULIAN_DAY             0       /* Jn = Julian day */
139 #define DAY_OF_YEAR            1       /* n = day of year */
140 #define MONTH_NTH_DAY_OF_WEEK  2       /* Mm.n.d = month, week, day of week */
141 
142 /*
143 ** Prototypes for static functions.
144 */
145 
146 /* NOTE: all internal functions assume that _tzLock() was already called */
147 
148 static int __bionic_open_tzdata(const char*, int*);
149 static int_fast32_t detzcode(const char * codep);
150 static int_fast64_t detzcode64(const char * codep);
151 static int      differ_by_repeat(time_t t1, time_t t0);
152 static const char * getzname(const char * strp) ATTRIBUTE_PURE;
153 static const char * getqzname(const char * strp, const int delim)
154         ATTRIBUTE_PURE;
155 static const char * getnum(const char * strp, int * nump, int min,
156                 int max);
157 static const char * getsecs(const char * strp, int_fast32_t * secsp);
158 static const char * getoffset(const char * strp, int_fast32_t * offsetp);
159 static const char * getrule(const char * strp, struct rule * rulep);
160 static void     gmtload(struct state * sp);
161 static struct tm *  gmtsub(const time_t * timep, int_fast32_t offset,
162                 struct tm * tmp, struct state * sp); // android-changed: added sp.
163 static struct tm *  localsub(const time_t * timep, int_fast32_t offset,
164                 struct tm * tmp, struct state * sp); // android-changed: added sp.
165 static int      increment_overflow(int * number, int delta);
166 static int      leaps_thru_end_of(int y) ATTRIBUTE_PURE;
167 static int      increment_overflow32(int_fast32_t * number, int delta);
168 static int      increment_overflow_time(time_t *t, int_fast32_t delta);
169 static int      normalize_overflow32(int_fast32_t * tensptr,
170                 int * unitsptr, int base);
171 static int      normalize_overflow(int * tensptr, int * unitsptr,
172                 int base);
173 static void     settzname(void);
174 static time_t       time1(struct tm * tmp,
175                 struct tm * (*funcp)(const time_t *,
176                 int_fast32_t, struct tm *, struct state *), // android-changed: added state*.
177                 int_fast32_t, struct state * sp); // android-changed: added sp.
178 static time_t       time2(struct tm * tmp,
179                 struct tm * (*funcp)(const time_t *,
180                 int_fast32_t, struct tm*, struct state *), // android-changed: added state*.
181                 int_fast32_t offset, int * okayp, struct state * sp); // android-changed: added sp.
182 static time_t       time2sub(struct tm *tmp,
183                 struct tm * (*funcp) (const time_t *,
184                 int_fast32_t, struct tm*, struct state *), // android-changed: added state*.
185                 int_fast32_t offset, int * okayp, int do_norm_secs, struct state * sp); // android-change: added sp.
186 static struct tm *  timesub(const time_t * timep, int_fast32_t offset,
187                 const struct state * sp, struct tm * tmp);
188 static int      tmcomp(const struct tm * atmp,
189                 const struct tm * btmp);
190 static int_fast32_t transtime(int year, const struct rule * rulep,
191                 int_fast32_t offset)
192         ATTRIBUTE_PURE;
193 static int      typesequiv(const struct state * sp, int a, int b);
194 static int      tzload(const char * name, struct state * sp,
195                 int doextend);
196 static int      tzparse(const char * name, struct state * sp,
197                 int lastditch);
198 
199 #ifdef ALL_STATE
200 static struct state * lclptr;
201 static struct state * gmtptr;
202 #endif /* defined ALL_STATE */
203 
204 #ifndef ALL_STATE
205 static struct state lclmem;
206 static struct state gmtmem;
207 #define lclptr      (&lclmem)
208 #define gmtptr      (&gmtmem)
209 #endif /* State Farm */
210 
211 #ifndef TZ_STRLEN_MAX
212 #define TZ_STRLEN_MAX 255
213 #endif /* !defined TZ_STRLEN_MAX */
214 
215 static char lcl_TZname[TZ_STRLEN_MAX + 1];
216 static int  lcl_is_set;
217 static int  gmt_is_set;
218 
219 char * tzname[2] = {
220     (char *) wildabbr,
221     (char *) wildabbr
222 };
223 
224 /*
225 ** Section 4.12.3 of X3.159-1989 requires that
226 **  Except for the strftime function, these functions [asctime,
227 **  ctime, gmtime, localtime] return values in one of two static
228 **  objects: a broken-down time structure and an array of char.
229 ** Thanks to Paul Eggert for noting this.
230 */
231 
232 static struct tm    tmGlobal;
233 
234 #ifdef USG_COMPAT
235 long                timezone = 0;
236 int                 daylight = 0;
237 #endif /* defined USG_COMPAT */
238 
239 #ifdef ALTZONE
240 long                altzone = 0;
241 #endif /* defined ALTZONE */
242 
243 static int_fast32_t
detzcode(const char * const codep)244 detzcode(const char *const codep)
245 {
246     register int_fast32_t result;
247     register int          i;
248 
249     result = (codep[0] & 0x80) ? -1 : 0;
250     for (i = 0; i < 4; ++i)
251         result = (result << 8) | (codep[i] & 0xff);
252     return result;
253 }
254 
255 static int_fast64_t
detzcode64(const char * const codep)256 detzcode64(const char *const codep)
257 {
258     register int_fast64_t result;
259     register int          i;
260 
261     result = (codep[0] & 0x80) ? -1 : 0;
262     for (i = 0; i < 8; ++i)
263         result = (result << 8) | (codep[i] & 0xff);
264     return result;
265 }
266 
267 static void
settzname(void)268 settzname(void)
269 {
270     register struct state * const sp = lclptr;
271     register int                  i;
272 
273     tzname[0] = tzname[1] = (char *) wildabbr;
274 #ifdef USG_COMPAT
275     daylight = 0;
276     timezone = 0;
277 #endif /* defined USG_COMPAT */
278 #ifdef ALTZONE
279     altzone = 0;
280 #endif /* defined ALTZONE */
281     if (sp == NULL) {
282         tzname[0] = tzname[1] = (char *) gmt;
283         return;
284     }
285     /*
286     ** And to get the latest zone names into tzname. . .
287     */
288     for (i = 0; i < sp->typecnt; ++i) {
289         register const struct ttinfo * const    ttisp = &sp->ttis[i];
290 
291         tzname[ttisp->tt_isdst] = &sp->chars[ttisp->tt_abbrind];
292     }
293     for (i = 0; i < sp->timecnt; ++i) {
294         register const struct ttinfo * const    ttisp =
295                             &sp->ttis[
296                                 sp->types[i]];
297 
298         tzname[ttisp->tt_isdst] =
299             &sp->chars[ttisp->tt_abbrind];
300 #ifdef USG_COMPAT
301         if (ttisp->tt_isdst)
302             daylight = 1;
303         if (!ttisp->tt_isdst)
304             timezone = -(ttisp->tt_gmtoff);
305 #endif /* defined USG_COMPAT */
306 #ifdef ALTZONE
307         if (ttisp->tt_isdst)
308             altzone = -(ttisp->tt_gmtoff);
309 #endif /* defined ALTZONE */
310     }
311     /*
312     ** Finally, scrub the abbreviations.
313     ** First, replace bogus characters.
314     */
315     for (i = 0; i < sp->charcnt; ++i)
316         if (strchr(TZ_ABBR_CHAR_SET, sp->chars[i]) == NULL)
317             sp->chars[i] = TZ_ABBR_ERR_CHAR;
318     /*
319     ** Second, truncate long abbreviations.
320     */
321     for (i = 0; i < sp->typecnt; ++i) {
322         register const struct ttinfo * const    ttisp = &sp->ttis[i];
323         register char *             cp = &sp->chars[ttisp->tt_abbrind];
324 
325         if (strlen(cp) > TZ_ABBR_MAX_LEN &&
326             strcmp(cp, GRANDPARENTED) != 0)
327                 *(cp + TZ_ABBR_MAX_LEN) = '\0';
328     }
329 }
330 
331 static int
differ_by_repeat(const time_t t1 __unused,const time_t t0 __unused)332 differ_by_repeat(const time_t t1 __unused, const time_t t0 __unused)
333 {
334     if (TYPE_BIT(time_t) - TYPE_SIGNED(time_t) < SECSPERREPEAT_BITS)
335         return 0;
336 #if defined(__LP64__) // 32-bit Android only has a signed 32-bit time_t; 64-bit Android is fixed.
337     return t1 - t0 == SECSPERREPEAT;
338 #endif
339 }
340 
341 static int
tzload(register const char * name,register struct state * const sp,register const int doextend)342 tzload(register const char* name, register struct state* const sp,
343        register const int doextend)
344 {
345     register const char * p;
346     register int          i;
347     register int          fid;
348     register int          stored;
349     register int          nread;
350     typedef union {
351         struct tzhead tzhead;
352         char          buf[2 * sizeof(struct tzhead) +
353                       2 * sizeof *sp +
354                       4 * TZ_MAX_TIMES];
355     } u_t;
356     union local_storage {
357         /*
358         ** Section 4.9.1 of the C standard says that
359         ** "FILENAME_MAX expands to an integral constant expression
360         ** that is the size needed for an array of char large enough
361         ** to hold the longest file name string that the implementation
362         ** guarantees can be opened."
363         */
364         //char            fullname[FILENAME_MAX + 1];
365 
366         /* The main part of the storage for this function.  */
367         struct {
368             u_t u;
369             struct state st;
370         } u;
371     };
372     //register char *fullname;
373     register u_t *up;
374     register union local_storage *lsp;
375 #ifdef ALL_STATE
376     lsp = malloc(sizeof *lsp);
377     if (!lsp)
378         return -1;
379 #else /* !defined ALL_STATE */
380     union local_storage ls;
381     lsp = &ls;
382 #endif /* !defined ALL_STATE */
383     //fullname = lsp->fullname;
384     up = &lsp->u.u;
385 
386     sp->goback = sp->goahead = FALSE;
387 
388     if (! name) {
389         name = TZDEFAULT;
390         if (! name)
391             goto oops;
392     }
393 
394     int toread;
395     fid = __bionic_open_tzdata(name, &toread);
396     if (fid < 0)
397         goto oops;
398 
399     nread = read(fid, up->buf, sizeof up->buf);
400     if (close(fid) < 0 || nread <= 0)
401         goto oops;
402     for (stored = 4; stored <= 8; stored *= 2) {
403         int ttisstdcnt;
404         int ttisgmtcnt;
405         int timecnt;
406 
407         ttisstdcnt = (int) detzcode(up->tzhead.tzh_ttisstdcnt);
408         ttisgmtcnt = (int) detzcode(up->tzhead.tzh_ttisgmtcnt);
409         sp->leapcnt = (int) detzcode(up->tzhead.tzh_leapcnt);
410         sp->timecnt = (int) detzcode(up->tzhead.tzh_timecnt);
411         sp->typecnt = (int) detzcode(up->tzhead.tzh_typecnt);
412         sp->charcnt = (int) detzcode(up->tzhead.tzh_charcnt);
413         p = up->tzhead.tzh_charcnt + sizeof up->tzhead.tzh_charcnt;
414         if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS ||
415             sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES ||
416             sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES ||
417             sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS ||
418             (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) ||
419             (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0))
420                 goto oops;
421         if (nread - (p - up->buf) <
422             sp->timecnt * stored +       /* ats */
423             sp->timecnt +                /* types */
424             sp->typecnt * 6 +            /* ttinfos */
425             sp->charcnt +                /* chars */
426             sp->leapcnt * (stored + 4) + /* lsinfos */
427             ttisstdcnt +                 /* ttisstds */
428             ttisgmtcnt)                  /* ttisgmts */
429                 goto oops;
430         timecnt = 0;
431         for (i = 0; i < sp->timecnt; ++i) {
432             int_fast64_t at
433               = stored == 4 ? detzcode(p) : detzcode64(p);
434             sp->types[i] = ((TYPE_SIGNED(time_t)
435                      ? time_t_min <= at
436                      : 0 <= at)
437                     && at <= time_t_max);
438             if (sp->types[i]) {
439                 if (i && !timecnt && at != time_t_min) {
440                     /*
441                     ** Keep the earlier record, but tweak
442                     ** it so that it starts with the
443                     ** minimum time_t value.
444                     */
445                     sp->types[i - 1] = 1;
446                     sp->ats[timecnt++] = time_t_min;
447                 }
448                 sp->ats[timecnt++] = at;
449             }
450             p += stored;
451         }
452         timecnt = 0;
453         for (i = 0; i < sp->timecnt; ++i) {
454             unsigned char typ = *p++;
455             if (sp->typecnt <= typ)
456                 goto oops;
457             if (sp->types[i])
458                 sp->types[timecnt++] = typ;
459         }
460         sp->timecnt = timecnt;
461         for (i = 0; i < sp->typecnt; ++i) {
462             register struct ttinfo *    ttisp;
463 
464             ttisp = &sp->ttis[i];
465             ttisp->tt_gmtoff = detzcode(p);
466             p += 4;
467             ttisp->tt_isdst = (unsigned char) *p++;
468             if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1)
469                 goto oops;
470             ttisp->tt_abbrind = (unsigned char) *p++;
471             if (ttisp->tt_abbrind < 0 ||
472                 ttisp->tt_abbrind > sp->charcnt)
473                     goto oops;
474         }
475         for (i = 0; i < sp->charcnt; ++i)
476             sp->chars[i] = *p++;
477         sp->chars[i] = '\0';    /* ensure '\0' at end */
478         for (i = 0; i < sp->leapcnt; ++i) {
479             register struct lsinfo *    lsisp;
480 
481             lsisp = &sp->lsis[i];
482             lsisp->ls_trans = (stored == 4) ?
483                 detzcode(p) : detzcode64(p);
484             p += stored;
485             lsisp->ls_corr = detzcode(p);
486             p += 4;
487         }
488         for (i = 0; i < sp->typecnt; ++i) {
489             register struct ttinfo *    ttisp;
490 
491             ttisp = &sp->ttis[i];
492             if (ttisstdcnt == 0)
493                 ttisp->tt_ttisstd = FALSE;
494             else {
495                 ttisp->tt_ttisstd = *p++;
496                 if (ttisp->tt_ttisstd != TRUE &&
497                     ttisp->tt_ttisstd != FALSE)
498                         goto oops;
499             }
500         }
501         for (i = 0; i < sp->typecnt; ++i) {
502             register struct ttinfo *    ttisp;
503 
504             ttisp = &sp->ttis[i];
505             if (ttisgmtcnt == 0)
506                 ttisp->tt_ttisgmt = FALSE;
507             else {
508                 ttisp->tt_ttisgmt = *p++;
509                 if (ttisp->tt_ttisgmt != TRUE &&
510                     ttisp->tt_ttisgmt != FALSE)
511                         goto oops;
512             }
513         }
514         /*
515         ** If this is an old file, we're done.
516         */
517         if (up->tzhead.tzh_version[0] == '\0')
518             break;
519         nread -= p - up->buf;
520         for (i = 0; i < nread; ++i)
521             up->buf[i] = p[i];
522         /*
523         ** If this is a signed narrow time_t system, we're done.
524         */
525         if (TYPE_SIGNED(time_t) && stored >= (int) sizeof(time_t))
526             break;
527     }
528     if (doextend && nread > 2 &&
529         up->buf[0] == '\n' && up->buf[nread - 1] == '\n' &&
530         sp->typecnt + 2 <= TZ_MAX_TYPES) {
531             struct state    *ts = &lsp->u.st;
532             register int result;
533 
534             up->buf[nread - 1] = '\0';
535             result = tzparse(&up->buf[1], ts, FALSE);
536             if (result == 0 && ts->typecnt == 2 &&
537                 sp->charcnt + ts->charcnt <= TZ_MAX_CHARS) {
538                     for (i = 0; i < 2; ++i)
539                         ts->ttis[i].tt_abbrind +=
540                             sp->charcnt;
541                     for (i = 0; i < ts->charcnt; ++i)
542                         sp->chars[sp->charcnt++] =
543                             ts->chars[i];
544                     i = 0;
545                     while (i < ts->timecnt &&
546                         ts->ats[i] <=
547                         sp->ats[sp->timecnt - 1])
548                             ++i;
549                     while (i < ts->timecnt &&
550                         sp->timecnt < TZ_MAX_TIMES) {
551                         sp->ats[sp->timecnt] =
552                             ts->ats[i];
553                         sp->types[sp->timecnt] =
554                             sp->typecnt +
555                             ts->types[i];
556                         ++sp->timecnt;
557                         ++i;
558                     }
559                     sp->ttis[sp->typecnt++] = ts->ttis[0];
560                     sp->ttis[sp->typecnt++] = ts->ttis[1];
561             }
562     }
563     if (sp->timecnt > 1) {
564         for (i = 1; i < sp->timecnt; ++i)
565             if (typesequiv(sp, sp->types[i], sp->types[0]) &&
566                     differ_by_repeat(sp->ats[i], sp->ats[0])) {
567                 sp->goback = TRUE;
568                 break;
569             }
570             for (i = sp->timecnt - 2; i >= 0; --i)
571                 if (typesequiv(sp, sp->types[sp->timecnt - 1],
572                                sp->types[i]) &&
573                         differ_by_repeat(sp->ats[sp->timecnt - 1],
574                                          sp->ats[i])) {
575                     sp->goahead = TRUE;
576                     break;
577             }
578         }
579         /*
580         ** If type 0 is is unused in transitions,
581         ** it's the type to use for early times.
582         */
583         for (i = 0; i < sp->typecnt; ++i)
584             if (sp->types[i] == 0)
585                 break;
586         i = (i >= sp->typecnt) ? 0 : -1;
587         /*
588         ** Absent the above,
589         ** if there are transition times
590         ** and the first transition is to a daylight time
591         ** find the standard type less than and closest to
592         ** the type of the first transition.
593         */
594         if (i < 0 && sp->timecnt > 0 && sp->ttis[sp->types[0]].tt_isdst) {
595             i = sp->types[0];
596             while (--i >= 0)
597                 if (!sp->ttis[i].tt_isdst)
598                     break;
599         }
600         /*
601         ** If no result yet, find the first standard type.
602         ** If there is none, punt to type zero.
603         */
604         if (i < 0) {
605             i = 0;
606             while (sp->ttis[i].tt_isdst)
607                 if (++i >= sp->typecnt) {
608                     i = 0;
609                     break;
610                 }
611         }
612         sp->defaulttype = i;
613 #ifdef ALL_STATE
614         free(up);
615 #endif /* defined ALL_STATE */
616         return 0;
617 oops:
618 #ifdef ALL_STATE
619         free(up);
620 #endif /* defined ALL_STATE */
621         return -1;
622 }
623 
624 static int
typesequiv(const struct state * const sp,const int a,const int b)625 typesequiv(const struct state *const sp, const int a, const int b)
626 {
627     register int result;
628 
629     if (sp == NULL ||
630         a < 0 || a >= sp->typecnt ||
631         b < 0 || b >= sp->typecnt)
632             result = FALSE;
633     else {
634         register const struct ttinfo *  ap = &sp->ttis[a];
635         register const struct ttinfo *  bp = &sp->ttis[b];
636         result = ap->tt_gmtoff == bp->tt_gmtoff &&
637             ap->tt_isdst == bp->tt_isdst &&
638             ap->tt_ttisstd == bp->tt_ttisstd &&
639             ap->tt_ttisgmt == bp->tt_ttisgmt &&
640             strcmp(&sp->chars[ap->tt_abbrind],
641             &sp->chars[bp->tt_abbrind]) == 0;
642     }
643     return result;
644 }
645 
646 static const int mon_lengths[2][MONSPERYEAR] = {
647     { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
648     { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }
649 };
650 
651 static const int year_lengths[2] = {
652     DAYSPERNYEAR, DAYSPERLYEAR
653 };
654 
655 /*
656 ** Given a pointer into a time zone string, scan until a character that is not
657 ** a valid character in a zone name is found. Return a pointer to that
658 ** character.
659 */
660 
661 static const char *
getzname(register const char * strp)662 getzname(register const char * strp)
663 {
664     register char   c;
665 
666     while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' &&
667         c != '+')
668             ++strp;
669     return strp;
670 }
671 
672 /*
673 ** Given a pointer into an extended time zone string, scan until the ending
674 ** delimiter of the zone name is located. Return a pointer to the delimiter.
675 **
676 ** As with getzname above, the legal character set is actually quite
677 ** restricted, with other characters producing undefined results.
678 ** We don't do any checking here; checking is done later in common-case code.
679 */
680 
681 static const char *
getqzname(register const char * strp,const int delim)682 getqzname(register const char *strp, const int delim)
683 {
684     register int c;
685 
686     while ((c = *strp) != '\0' && c != delim)
687         ++strp;
688     return strp;
689 }
690 
691 /*
692 ** Given a pointer into a time zone string, extract a number from that string.
693 ** Check that the number is within a specified range; if it is not, return
694 ** NULL.
695 ** Otherwise, return a pointer to the first character not part of the number.
696 */
697 
698 static const char *
getnum(register const char * strp,int * const nump,const int min,const int max)699 getnum(register const char * strp, int * const nump, const int min, const int max)
700 {
701     register char c;
702     register int  num;
703 
704     if (strp == NULL || !is_digit(c = *strp))
705         return NULL;
706     num = 0;
707     do {
708         num = num * 10 + (c - '0');
709         if (num > max)
710             return NULL;    /* illegal value */
711         c = *++strp;
712     } while (is_digit(c));
713     if (num < min)
714         return NULL;        /* illegal value */
715     *nump = num;
716     return strp;
717 }
718 
719 /*
720 ** Given a pointer into a time zone string, extract a number of seconds,
721 ** in hh[:mm[:ss]] form, from the string.
722 ** If any error occurs, return NULL.
723 ** Otherwise, return a pointer to the first character not part of the number
724 ** of seconds.
725 */
726 
727 static const char *
getsecs(register const char * strp,int_fast32_t * const secsp)728 getsecs(register const char *strp, int_fast32_t *const secsp)
729 {
730     int num;
731 
732     /*
733     ** 'HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like
734     ** "M10.4.6/26", which does not conform to Posix,
735     ** but which specifies the equivalent of
736     ** "02:00 on the first Sunday on or after 23 Oct".
737     */
738     strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1);
739     if (strp == NULL)
740         return NULL;
741     *secsp = num * (int_fast32_t) SECSPERHOUR;
742     if (*strp == ':') {
743         ++strp;
744         strp = getnum(strp, &num, 0, MINSPERHOUR - 1);
745         if (strp == NULL)
746             return NULL;
747         *secsp += num * SECSPERMIN;
748         if (*strp == ':') {
749             ++strp;
750             /* 'SECSPERMIN' allows for leap seconds. */
751             strp = getnum(strp, &num, 0, SECSPERMIN);
752             if (strp == NULL)
753                 return NULL;
754             *secsp += num;
755         }
756     }
757     return strp;
758 }
759 
760 /*
761 ** Given a pointer into a time zone string, extract an offset, in
762 ** [+-]hh[:mm[:ss]] form, from the string.
763 ** If any error occurs, return NULL.
764 ** Otherwise, return a pointer to the first character not part of the time.
765 */
766 
767 static const char *
getoffset(register const char * strp,int_fast32_t * const offsetp)768 getoffset(register const char *strp, int_fast32_t *const offsetp)
769 {
770     register int neg = 0;
771 
772     if (*strp == '-') {
773         neg = 1;
774         ++strp;
775     } else if (*strp == '+')
776         ++strp;
777     strp = getsecs(strp, offsetp);
778     if (strp == NULL)
779         return NULL;        /* illegal time */
780     if (neg)
781         *offsetp = -*offsetp;
782     return strp;
783 }
784 
785 /*
786 ** Given a pointer into a time zone string, extract a rule in the form
787 ** date[/time]. See POSIX section 8 for the format of "date" and "time".
788 ** If a valid rule is not found, return NULL.
789 ** Otherwise, return a pointer to the first character not part of the rule.
790 */
791 
792 static const char *
getrule(const char * strp,register struct rule * const rulep)793 getrule(const char * strp, register struct rule * const rulep)
794 {
795     if (*strp == 'J') {
796         /*
797         ** Julian day.
798         */
799         rulep->r_type = JULIAN_DAY;
800         ++strp;
801         strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR);
802     } else if (*strp == 'M') {
803         /*
804         ** Month, week, day.
805         */
806         rulep->r_type = MONTH_NTH_DAY_OF_WEEK;
807         ++strp;
808         strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR);
809         if (strp == NULL)
810             return NULL;
811         if (*strp++ != '.')
812             return NULL;
813         strp = getnum(strp, &rulep->r_week, 1, 5);
814         if (strp == NULL)
815             return NULL;
816         if (*strp++ != '.')
817             return NULL;
818         strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1);
819     } else if (is_digit(*strp)) {
820         /*
821         ** Day of year.
822         */
823         rulep->r_type = DAY_OF_YEAR;
824         strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1);
825     } else  return NULL;        /* invalid format */
826     if (strp == NULL)
827         return NULL;
828     if (*strp == '/') {
829         /*
830         ** Time specified.
831         */
832         ++strp;
833         strp = getoffset(strp, &rulep->r_time);
834     } else  rulep->r_time = 2 * SECSPERHOUR;    /* default = 2:00:00 */
835     return strp;
836 }
837 
838 /*
839 ** Given a year, a rule, and the offset from UT at the time that rule takes
840 ** effect, calculate the year-relative time that rule takes effect.
841 */
842 
843 static int_fast32_t
transtime(const int year,register const struct rule * const rulep,const int_fast32_t offset)844 transtime(const int year, register const struct rule *const rulep,
845           const int_fast32_t offset)
846 {
847     register int          leapyear;
848     register int_fast32_t value;
849     register int          i;
850     int d, m1, yy0, yy1, yy2, dow;
851 
852     INITIALIZE(value);
853     leapyear = isleap(year);
854     switch (rulep->r_type) {
855 
856     case JULIAN_DAY:
857         /*
858         ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap
859         ** years.
860         ** In non-leap years, or if the day number is 59 or less, just
861         ** add SECSPERDAY times the day number-1 to the time of
862         ** January 1, midnight, to get the day.
863         */
864         value = (rulep->r_day - 1) * SECSPERDAY;
865         if (leapyear && rulep->r_day >= 60)
866             value += SECSPERDAY;
867         break;
868 
869     case DAY_OF_YEAR:
870         /*
871         ** n - day of year.
872         ** Just add SECSPERDAY times the day number to the time of
873         ** January 1, midnight, to get the day.
874         */
875         value = rulep->r_day * SECSPERDAY;
876         break;
877 
878     case MONTH_NTH_DAY_OF_WEEK:
879         /*
880         ** Mm.n.d - nth "dth day" of month m.
881         */
882 
883         /*
884         ** Use Zeller's Congruence to get day-of-week of first day of
885         ** month.
886         */
887         m1 = (rulep->r_mon + 9) % 12 + 1;
888         yy0 = (rulep->r_mon <= 2) ? (year - 1) : year;
889         yy1 = yy0 / 100;
890         yy2 = yy0 % 100;
891         dow = ((26 * m1 - 2) / 10 +
892             1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7;
893         if (dow < 0)
894             dow += DAYSPERWEEK;
895 
896         /*
897         ** "dow" is the day-of-week of the first day of the month. Get
898         ** the day-of-month (zero-origin) of the first "dow" day of the
899         ** month.
900         */
901         d = rulep->r_day - dow;
902         if (d < 0)
903             d += DAYSPERWEEK;
904         for (i = 1; i < rulep->r_week; ++i) {
905             if (d + DAYSPERWEEK >=
906                 mon_lengths[leapyear][rulep->r_mon - 1])
907                     break;
908             d += DAYSPERWEEK;
909         }
910 
911         /*
912         ** "d" is the day-of-month (zero-origin) of the day we want.
913         */
914         value = d * SECSPERDAY;
915         for (i = 0; i < rulep->r_mon - 1; ++i)
916             value += mon_lengths[leapyear][i] * SECSPERDAY;
917         break;
918     }
919 
920     /*
921     ** "value" is the year-relative time of 00:00:00 UT on the day in
922     ** question. To get the year-relative time of the specified local
923     ** time on that day, add the transition time and the current offset
924     ** from UT.
925     */
926     return value + rulep->r_time + offset;
927 }
928 
929 /*
930 ** Given a POSIX section 8-style TZ string, fill in the rule tables as
931 ** appropriate.
932 */
933 
934 static int
tzparse(const char * name,register struct state * const sp,const int lastditch)935 tzparse(const char * name, register struct state * const sp,
936         const int lastditch)
937 {
938     const char *         stdname;
939     const char *         dstname;
940     size_t               stdlen;
941     size_t               dstlen;
942     int_fast32_t         stdoffset;
943     int_fast32_t         dstoffset;
944     register char *      cp;
945     register int         load_result;
946     static struct ttinfo zttinfo;
947 
948     stdname = name;
949     if (lastditch) {
950         stdlen = strlen(name);  /* length of standard zone name */
951         name += stdlen;
952         if (stdlen >= sizeof sp->chars)
953             stdlen = (sizeof sp->chars) - 1;
954         stdoffset = 0;
955     } else {
956         if (*name == '<') {
957             name++;
958             stdname = name;
959             name = getqzname(name, '>');
960             if (*name != '>')
961                 return (-1);
962             stdlen = name - stdname;
963             name++;
964         } else {
965             name = getzname(name);
966             stdlen = name - stdname;
967         }
968         if (*name == '\0')
969             return -1;
970         name = getoffset(name, &stdoffset);
971         if (name == NULL)
972             return -1;
973     }
974     load_result = tzload(TZDEFRULES, sp, FALSE);
975     if (load_result != 0)
976         sp->leapcnt = 0;        /* so, we're off a little */
977     if (*name != '\0') {
978         if (*name == '<') {
979             dstname = ++name;
980             name = getqzname(name, '>');
981             if (*name != '>')
982                 return -1;
983             dstlen = name - dstname;
984             name++;
985         } else {
986             dstname = name;
987             name = getzname(name);
988             dstlen = name - dstname; /* length of DST zone name */
989         }
990         if (*name != '\0' && *name != ',' && *name != ';') {
991             name = getoffset(name, &dstoffset);
992             if (name == NULL)
993                 return -1;
994         } else  dstoffset = stdoffset - SECSPERHOUR;
995         if (*name == '\0' && load_result != 0)
996             name = TZDEFRULESTRING;
997         if (*name == ',' || *name == ';') {
998             struct rule  start;
999             struct rule  end;
1000             register int year;
1001             register int yearlim;
1002             register int timecnt;
1003             time_t       janfirst;
1004 
1005             ++name;
1006             if ((name = getrule(name, &start)) == NULL)
1007                 return -1;
1008             if (*name++ != ',')
1009                 return -1;
1010             if ((name = getrule(name, &end)) == NULL)
1011                 return -1;
1012             if (*name != '\0')
1013                 return -1;
1014             sp->typecnt = 2;    /* standard time and DST */
1015             /*
1016             ** Two transitions per year, from EPOCH_YEAR forward.
1017             */
1018             sp->ttis[0] = sp->ttis[1] = zttinfo;
1019             sp->ttis[0].tt_gmtoff = -dstoffset;
1020             sp->ttis[0].tt_isdst = 1;
1021             sp->ttis[0].tt_abbrind = stdlen + 1;
1022             sp->ttis[1].tt_gmtoff = -stdoffset;
1023             sp->ttis[1].tt_isdst = 0;
1024             sp->ttis[1].tt_abbrind = 0;
1025             sp->defaulttype = 0;
1026             timecnt = 0;
1027             janfirst = 0;
1028             yearlim = EPOCH_YEAR + YEARSPERREPEAT;
1029             for (year = EPOCH_YEAR; year < yearlim; year++) {
1030                 int_fast32_t
1031                   starttime = transtime(year, &start, stdoffset),
1032                   endtime = transtime(year, &end, dstoffset);
1033                 int_fast32_t
1034                 yearsecs = (year_lengths[isleap(year)]
1035                             * SECSPERDAY);
1036                 int reversed = endtime < starttime;
1037                 if (reversed) {
1038                     int_fast32_t swap = starttime;
1039                     starttime = endtime;
1040                     endtime = swap;
1041                 }
1042                 if (reversed
1043                     || (starttime < endtime
1044                         && (endtime - starttime
1045                             < (yearsecs
1046                                + (stdoffset - dstoffset))))) {
1047                     if (TZ_MAX_TIMES - 2 < timecnt)
1048                         break;
1049                     yearlim = year + YEARSPERREPEAT + 1;
1050                     sp->ats[timecnt] = janfirst;
1051                     if (increment_overflow_time
1052                         (&sp->ats[timecnt], starttime))
1053                         break;
1054                     sp->types[timecnt++] = reversed;
1055                     sp->ats[timecnt] = janfirst;
1056                     if (increment_overflow_time
1057                         (&sp->ats[timecnt], endtime))
1058                         break;
1059                     sp->types[timecnt++] = !reversed;
1060                     }
1061                 if (increment_overflow_time(&janfirst, yearsecs))
1062                     break;
1063             }
1064             sp->timecnt = timecnt;
1065             if (!timecnt)
1066                 sp->typecnt = 1;    /* Perpetual DST.  */
1067         } else {
1068             register int_fast32_t   theirstdoffset;
1069             register int_fast32_t   theirdstoffset;
1070             register int_fast32_t   theiroffset;
1071             register int    isdst;
1072             register int    i;
1073             register int    j;
1074 
1075             if (*name != '\0')
1076                 return -1;
1077             /*
1078             ** Initial values of theirstdoffset and theirdstoffset.
1079             */
1080             theirstdoffset = 0;
1081             for (i = 0; i < sp->timecnt; ++i) {
1082                 j = sp->types[i];
1083                 if (!sp->ttis[j].tt_isdst) {
1084                     theirstdoffset =
1085                         -sp->ttis[j].tt_gmtoff;
1086                     break;
1087                 }
1088             }
1089             theirdstoffset = 0;
1090             for (i = 0; i < sp->timecnt; ++i) {
1091                 j = sp->types[i];
1092                 if (sp->ttis[j].tt_isdst) {
1093                     theirdstoffset =
1094                         -sp->ttis[j].tt_gmtoff;
1095                     break;
1096                 }
1097             }
1098             /*
1099             ** Initially we're assumed to be in standard time.
1100             */
1101             isdst = FALSE;
1102             theiroffset = theirstdoffset;
1103             /*
1104             ** Now juggle transition times and types
1105             ** tracking offsets as you do.
1106             */
1107             for (i = 0; i < sp->timecnt; ++i) {
1108                 j = sp->types[i];
1109                 sp->types[i] = sp->ttis[j].tt_isdst;
1110                 if (sp->ttis[j].tt_ttisgmt) {
1111                     /* No adjustment to transition time */
1112                 } else {
1113                     /*
1114                     ** If summer time is in effect, and the
1115                     ** transition time was not specified as
1116                     ** standard time, add the summer time
1117                     ** offset to the transition time;
1118                     ** otherwise, add the standard time
1119                     ** offset to the transition time.
1120                     */
1121                     /*
1122                     ** Transitions from DST to DDST
1123                     ** will effectively disappear since
1124                     ** POSIX provides for only one DST
1125                     ** offset.
1126                     */
1127                     if (isdst && !sp->ttis[j].tt_ttisstd) {
1128                         sp->ats[i] += dstoffset -
1129                             theirdstoffset;
1130                     } else {
1131                         sp->ats[i] += stdoffset -
1132                             theirstdoffset;
1133                     }
1134                 }
1135                 theiroffset = -sp->ttis[j].tt_gmtoff;
1136                 if (sp->ttis[j].tt_isdst)
1137                     theirdstoffset = theiroffset;
1138                 else    theirstdoffset = theiroffset;
1139             }
1140             /*
1141             ** Finally, fill in ttis.
1142             */
1143             sp->ttis[0] = sp->ttis[1] = zttinfo;
1144             sp->ttis[0].tt_gmtoff = -stdoffset;
1145             sp->ttis[0].tt_isdst = FALSE;
1146             sp->ttis[0].tt_abbrind = 0;
1147             sp->ttis[1].tt_gmtoff = -dstoffset;
1148             sp->ttis[1].tt_isdst = TRUE;
1149             sp->ttis[1].tt_abbrind = stdlen + 1;
1150             sp->typecnt = 2;
1151             sp->defaulttype = 0;
1152         }
1153     } else {
1154         dstlen = 0;
1155         sp->typecnt = 1;        /* only standard time */
1156         sp->timecnt = 0;
1157         sp->ttis[0] = zttinfo;
1158         sp->ttis[0].tt_gmtoff = -stdoffset;
1159         sp->ttis[0].tt_isdst = 0;
1160         sp->ttis[0].tt_abbrind = 0;
1161         sp->defaulttype = 0;
1162     }
1163     sp->charcnt = stdlen + 1;
1164     if (dstlen != 0)
1165         sp->charcnt += dstlen + 1;
1166     if ((size_t) sp->charcnt > sizeof sp->chars)
1167         return -1;
1168     cp = sp->chars;
1169     (void) strncpy(cp, stdname, stdlen);
1170     cp += stdlen;
1171     *cp++ = '\0';
1172     if (dstlen != 0) {
1173         (void) strncpy(cp, dstname, dstlen);
1174         *(cp + dstlen) = '\0';
1175     }
1176     return 0;
1177 }
1178 
1179 static void
gmtload(struct state * const sp)1180 gmtload(struct state * const sp)
1181 {
1182     if (tzload(gmt, sp, TRUE) != 0)
1183         (void) tzparse(gmt, sp, TRUE);
1184 }
1185 
1186 #ifndef STD_INSPIRED
1187 /*
1188 ** A non-static declaration of tzsetwall in a system header file
1189 ** may cause a warning about this upcoming static declaration...
1190 */
1191 static
1192 #endif /* !defined STD_INSPIRED */
1193 void
tzsetwall(void)1194 tzsetwall(void)
1195 {
1196     if (lcl_is_set < 0)
1197         return;
1198     lcl_is_set = -1;
1199 
1200 #ifdef ALL_STATE
1201     if (lclptr == NULL) {
1202         lclptr = malloc(sizeof *lclptr);
1203         if (lclptr == NULL) {
1204             settzname();    /* all we can do */
1205             return;
1206         }
1207     }
1208 #endif /* defined ALL_STATE */
1209     if (tzload(NULL, lclptr, TRUE) != 0)
1210         gmtload(lclptr);
1211     settzname();
1212 }
1213 
1214 #include <sys/system_properties.h> // For __system_property_get.
1215 
1216 static void
tzset_locked(void)1217 tzset_locked(void)
1218 {
1219     register const char * name;
1220 
1221     name = getenv("TZ");
1222 
1223     // try the "persist.sys.timezone" system property first
1224     static char buf[PROP_VALUE_MAX];
1225     if (name == NULL && __system_property_get("persist.sys.timezone", buf) > 0) {
1226         name = buf;
1227     }
1228 
1229     if (name == NULL) {
1230         tzsetwall();
1231         return;
1232     }
1233 
1234     if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0)
1235         return;
1236     lcl_is_set = strlen(name) < sizeof lcl_TZname;
1237     if (lcl_is_set)
1238         (void) strcpy(lcl_TZname, name);
1239 
1240 #ifdef ALL_STATE
1241     if (lclptr == NULL) {
1242         lclptr = malloc(sizeof *lclptr);
1243         if (lclptr == NULL) {
1244             settzname();    /* all we can do */
1245             return;
1246         }
1247     }
1248 #endif /* defined ALL_STATE */
1249     if (*name == '\0') {
1250         /*
1251         ** User wants it fast rather than right.
1252         */
1253         lclptr->leapcnt = 0;        /* so, we're off a little */
1254         lclptr->timecnt = 0;
1255         lclptr->typecnt = 0;
1256         lclptr->ttis[0].tt_isdst = 0;
1257         lclptr->ttis[0].tt_gmtoff = 0;
1258         lclptr->ttis[0].tt_abbrind = 0;
1259         (void) strcpy(lclptr->chars, gmt);
1260     } else if (tzload(name, lclptr, TRUE) != 0)
1261         if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0)
1262             (void) gmtload(lclptr);
1263     settzname();
1264 }
1265 
1266 void
tzset(void)1267 tzset(void)
1268 {
1269     _tzLock();
1270     tzset_locked();
1271     _tzUnlock();
1272 }
1273 
1274 /*
1275 ** The easy way to behave "as if no library function calls" localtime
1276 ** is to not call it--so we drop its guts into "localsub", which can be
1277 ** freely called. (And no, the PANS doesn't require the above behavior--
1278 ** but it *is* desirable.)
1279 **
1280 ** The unused offset argument is for the benefit of mktime variants.
1281 */
1282 
1283 /*ARGSUSED*/
1284 static struct tm *
localsub(const time_t * const timep,const int_fast32_t offset,struct tm * const tmp,struct state * sp)1285 localsub(const time_t * const timep, const int_fast32_t offset,
1286          struct tm * const tmp, struct state * sp) // android-changed: added sp.
1287 {
1288     register const struct ttinfo * ttisp;
1289     register int         i;
1290     register struct tm * result;
1291     const time_t         t = *timep;
1292 
1293     // BEGIN android-changed: support user-supplied sp.
1294     if (sp == NULL) {
1295         sp = lclptr;
1296     }
1297     // END android-changed
1298     if (sp == NULL)
1299         return gmtsub(timep, offset, tmp, sp); // android-changed: added sp.
1300     if ((sp->goback && t < sp->ats[0]) ||
1301         (sp->goahead && t > sp->ats[sp->timecnt - 1])) {
1302             time_t          newt = t;
1303             register time_t seconds;
1304             register time_t years;
1305 
1306             if (t < sp->ats[0])
1307                 seconds = sp->ats[0] - t;
1308             else    seconds = t - sp->ats[sp->timecnt - 1];
1309             --seconds;
1310             years = (seconds / SECSPERREPEAT + 1) * YEARSPERREPEAT;
1311             seconds = years * AVGSECSPERYEAR;
1312             if (t < sp->ats[0])
1313                 newt += seconds;
1314             else    newt -= seconds;
1315             if (newt < sp->ats[0] ||
1316                 newt > sp->ats[sp->timecnt - 1])
1317                     return NULL;    /* "cannot happen" */
1318             result = localsub(&newt, offset, tmp, sp); // android-changed: added sp.
1319             if (result == tmp) {
1320                 register time_t newy;
1321 
1322                 newy = tmp->tm_year;
1323                 if (t < sp->ats[0])
1324                     newy -= years;
1325                 else    newy += years;
1326                 tmp->tm_year = newy;
1327                 if (tmp->tm_year != newy)
1328                     return NULL;
1329             }
1330             return result;
1331     }
1332     if (sp->timecnt == 0 || t < sp->ats[0]) {
1333         i = sp->defaulttype;
1334     } else {
1335         register int lo = 1;
1336         register int hi = sp->timecnt;
1337 
1338         while (lo < hi) {
1339             register int    mid = (lo + hi) >> 1;
1340 
1341             if (t < sp->ats[mid])
1342                 hi = mid;
1343             else    lo = mid + 1;
1344         }
1345         i = (int) sp->types[lo - 1];
1346     }
1347     ttisp = &sp->ttis[i];
1348     /*
1349     ** To get (wrong) behavior that's compatible with System V Release 2.0
1350     ** you'd replace the statement below with
1351     **  t += ttisp->tt_gmtoff;
1352     **  timesub(&t, 0L, sp, tmp);
1353     */
1354     result = timesub(&t, ttisp->tt_gmtoff, sp, tmp);
1355     tmp->tm_isdst = ttisp->tt_isdst;
1356     tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind];
1357 #ifdef TM_ZONE
1358     tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind];
1359 #endif /* defined TM_ZONE */
1360     return result;
1361 }
1362 
1363 struct tm *
localtime(const time_t * const timep)1364 localtime(const time_t * const timep)
1365 {
1366     return localtime_r(timep, &tmGlobal);
1367 }
1368 
1369 /*
1370 ** Re-entrant version of localtime.
1371 */
1372 
1373 struct tm *
localtime_r(const time_t * const timep,struct tm * tmp)1374 localtime_r(const time_t * const timep, struct tm * tmp)
1375 {
1376     struct tm* result;
1377 
1378     _tzLock();
1379     tzset_locked();
1380     result = localsub(timep, 0L, tmp, NULL); // android-changed: extra parameter.
1381     _tzUnlock();
1382 
1383     return result;
1384 }
1385 
1386 /*
1387 ** gmtsub is to gmtime as localsub is to localtime.
1388 */
1389 
1390 static struct tm *
gmtsub(const time_t * const timep,const int_fast32_t offset,struct tm * const tmp,struct state * sp __unused)1391 gmtsub(const time_t * const timep, const int_fast32_t offset,
1392        struct tm *const tmp, struct state * sp __unused) // android-changed: added sp.
1393 {
1394     register struct tm * result;
1395 
1396     if (!gmt_is_set) {
1397 #ifdef ALL_STATE
1398         gmtptr = malloc(sizeof *gmtptr);
1399         gmt_is_set = gmtptr != NULL;
1400 #else
1401         gmt_is_set = TRUE;
1402 #endif /* defined ALL_STATE */
1403         if (gmt_is_set)
1404             gmtload(gmtptr);
1405     }
1406     result = timesub(timep, offset, gmtptr, tmp);
1407 #ifdef TM_ZONE
1408     /*
1409     ** Could get fancy here and deliver something such as
1410     ** "UT+xxxx" or "UT-xxxx" if offset is non-zero,
1411     ** but this is no time for a treasure hunt.
1412     */
1413     tmp->TM_ZONE = offset ? wildabbr : gmtptr ? gmtptr->chars : gmt;
1414 #endif /* defined TM_ZONE */
1415     return result;
1416 }
1417 
1418 struct tm *
gmtime(const time_t * const timep)1419 gmtime(const time_t * const timep)
1420 {
1421     return gmtime_r(timep, &tmGlobal);
1422 }
1423 
1424 /*
1425 * Re-entrant version of gmtime.
1426 */
1427 
1428 struct tm *
gmtime_r(const time_t * const timep,struct tm * tmp)1429 gmtime_r(const time_t * const timep, struct tm * tmp)
1430 {
1431     struct tm* result;
1432 
1433     _tzLock();
1434     result = gmtsub(timep, 0L, tmp, NULL); // android-changed: extra parameter.
1435     _tzUnlock();
1436 
1437     return result;
1438 }
1439 
1440 #ifdef STD_INSPIRED
1441 
1442 struct tm *
offtime(const time_t * const timep,const long offset)1443 offtime(const time_t *const timep, const long offset)
1444 {
1445     return gmtsub(timep, offset, &tmGlobal, NULL); // android-changed: extra parameter.
1446 }
1447 
1448 #endif /* defined STD_INSPIRED */
1449 
1450 /*
1451 ** Return the number of leap years through the end of the given year
1452 ** where, to make the math easy, the answer for year zero is defined as zero.
1453 */
1454 
1455 static int
leaps_thru_end_of(register const int y)1456 leaps_thru_end_of(register const int y)
1457 {
1458     return (y >= 0) ? (y / 4 - y / 100 + y / 400) :
1459         -(leaps_thru_end_of(-(y + 1)) + 1);
1460 }
1461 
1462 static struct tm *
timesub(const time_t * const timep,const int_fast32_t offset,register const struct state * const sp,register struct tm * const tmp)1463 timesub(const time_t *const timep, const int_fast32_t offset,
1464         register const struct state *const sp,
1465         register struct tm *const tmp)
1466 {
1467     register const struct lsinfo * lp;
1468     register time_t       tdays;
1469     register int          idays;  /* unsigned would be so 2003 */
1470     register int_fast64_t rem;
1471     int                   y;
1472     register const int *  ip;
1473     register int_fast64_t corr;
1474     register int          hit;
1475     register int          i;
1476 
1477     corr = 0;
1478     hit = 0;
1479     i = (sp == NULL) ? 0 : sp->leapcnt;
1480     while (--i >= 0) {
1481         lp = &sp->lsis[i];
1482         if (*timep >= lp->ls_trans) {
1483             if (*timep == lp->ls_trans) {
1484                 hit = ((i == 0 && lp->ls_corr > 0) ||
1485                     lp->ls_corr > sp->lsis[i - 1].ls_corr);
1486                 if (hit)
1487                     while (i > 0 &&
1488                         sp->lsis[i].ls_trans ==
1489                         sp->lsis[i - 1].ls_trans + 1 &&
1490                         sp->lsis[i].ls_corr ==
1491                         sp->lsis[i - 1].ls_corr + 1) {
1492                             ++hit;
1493                             --i;
1494                     }
1495             }
1496             corr = lp->ls_corr;
1497             break;
1498         }
1499     }
1500     y = EPOCH_YEAR;
1501     tdays = *timep / SECSPERDAY;
1502     rem = *timep - tdays * SECSPERDAY;
1503     while (tdays < 0 || tdays >= year_lengths[isleap(y)]) {
1504         int     newy;
1505         register time_t tdelta;
1506         register int    idelta;
1507         register int    leapdays;
1508 
1509         tdelta = tdays / DAYSPERLYEAR;
1510         if (! ((! TYPE_SIGNED(time_t) || INT_MIN <= tdelta)
1511                && tdelta <= INT_MAX))
1512                 return NULL;
1513         idelta = tdelta;
1514         if (idelta == 0)
1515             idelta = (tdays < 0) ? -1 : 1;
1516         newy = y;
1517         if (increment_overflow(&newy, idelta))
1518             return NULL;
1519         leapdays = leaps_thru_end_of(newy - 1) -
1520             leaps_thru_end_of(y - 1);
1521         tdays -= ((time_t) newy - y) * DAYSPERNYEAR;
1522         tdays -= leapdays;
1523         y = newy;
1524     }
1525     {
1526         register int_fast32_t   seconds;
1527 
1528         seconds = tdays * SECSPERDAY;
1529         tdays = seconds / SECSPERDAY;
1530         rem += seconds - tdays * SECSPERDAY;
1531     }
1532     /*
1533     ** Given the range, we can now fearlessly cast...
1534     */
1535     idays = tdays;
1536     rem += offset - corr;
1537     while (rem < 0) {
1538         rem += SECSPERDAY;
1539         --idays;
1540     }
1541     while (rem >= SECSPERDAY) {
1542         rem -= SECSPERDAY;
1543         ++idays;
1544     }
1545     while (idays < 0) {
1546         if (increment_overflow(&y, -1))
1547             return NULL;
1548         idays += year_lengths[isleap(y)];
1549     }
1550     while (idays >= year_lengths[isleap(y)]) {
1551         idays -= year_lengths[isleap(y)];
1552         if (increment_overflow(&y, 1))
1553             return NULL;
1554     }
1555     tmp->tm_year = y;
1556     if (increment_overflow(&tmp->tm_year, -TM_YEAR_BASE))
1557         return NULL;
1558     tmp->tm_yday = idays;
1559     /*
1560     ** The "extra" mods below avoid overflow problems.
1561     */
1562     tmp->tm_wday = EPOCH_WDAY +
1563         ((y - EPOCH_YEAR) % DAYSPERWEEK) *
1564         (DAYSPERNYEAR % DAYSPERWEEK) +
1565         leaps_thru_end_of(y - 1) -
1566         leaps_thru_end_of(EPOCH_YEAR - 1) +
1567         idays;
1568     tmp->tm_wday %= DAYSPERWEEK;
1569     if (tmp->tm_wday < 0)
1570         tmp->tm_wday += DAYSPERWEEK;
1571     tmp->tm_hour = (int) (rem / SECSPERHOUR);
1572     rem %= SECSPERHOUR;
1573     tmp->tm_min = (int) (rem / SECSPERMIN);
1574     /*
1575     ** A positive leap second requires a special
1576     ** representation. This uses "... ??:59:60" et seq.
1577     */
1578     tmp->tm_sec = (int) (rem % SECSPERMIN) + hit;
1579     ip = mon_lengths[isleap(y)];
1580     for (tmp->tm_mon = 0; idays >= ip[tmp->tm_mon]; ++(tmp->tm_mon))
1581         idays -= ip[tmp->tm_mon];
1582     tmp->tm_mday = (int) (idays + 1);
1583     tmp->tm_isdst = 0;
1584 #ifdef TM_GMTOFF
1585     tmp->TM_GMTOFF = offset;
1586 #endif /* defined TM_GMTOFF */
1587     return tmp;
1588 }
1589 
1590 char *
ctime(const time_t * const timep)1591 ctime(const time_t * const timep)
1592 {
1593 /*
1594 ** Section 4.12.3.2 of X3.159-1989 requires that
1595 **  The ctime function converts the calendar time pointed to by timer
1596 **  to local time in the form of a string. It is equivalent to
1597 **      asctime(localtime(timer))
1598 */
1599     return asctime(localtime(timep));
1600 }
1601 
1602 char *
ctime_r(const time_t * const timep,char * buf)1603 ctime_r(const time_t * const timep, char * buf)
1604 {
1605     struct tm   mytm;
1606 
1607     return asctime_r(localtime_r(timep, &mytm), buf);
1608 }
1609 
1610 /*
1611 ** Adapted from code provided by Robert Elz, who writes:
1612 **  The "best" way to do mktime I think is based on an idea of Bob
1613 **  Kridle's (so its said...) from a long time ago.
1614 **  It does a binary search of the time_t space. Since time_t's are
1615 **  just 32 bits, its a max of 32 iterations (even at 64 bits it
1616 **  would still be very reasonable).
1617 */
1618 
1619 #ifndef WRONG
1620 #define WRONG   (-1)
1621 #endif /* !defined WRONG */
1622 
1623 /*
1624 ** Normalize logic courtesy Paul Eggert.
1625 */
1626 
1627 static int
increment_overflow(int * const ip,int j)1628 increment_overflow(int *const ip, int j)
1629 {
1630     register int const i = *ip;
1631 
1632     /*
1633     ** If i >= 0 there can only be overflow if i + j > INT_MAX
1634     ** or if j > INT_MAX - i; given i >= 0, INT_MAX - i cannot overflow.
1635     ** If i < 0 there can only be overflow if i + j < INT_MIN
1636     ** or if j < INT_MIN - i; given i < 0, INT_MIN - i cannot overflow.
1637     */
1638     if ((i >= 0) ? (j > INT_MAX - i) : (j < INT_MIN - i))
1639         return TRUE;
1640     *ip += j;
1641     return FALSE;
1642 }
1643 
1644 static int
increment_overflow32(int_fast32_t * const lp,int const m)1645 increment_overflow32(int_fast32_t *const lp, int const m)
1646 {
1647     register int_fast32_t const l = *lp;
1648 
1649     if ((l >= 0) ? (m > INT_FAST32_MAX - l) : (m < INT_FAST32_MIN - l))
1650         return TRUE;
1651     *lp += m;
1652     return FALSE;
1653 }
1654 
1655 static int
increment_overflow_time(time_t * tp,int_fast32_t j)1656 increment_overflow_time(time_t *tp, int_fast32_t j)
1657 {
1658     /*
1659     ** This is like
1660     ** 'if (! (time_t_min <= *tp + j && *tp + j <= time_t_max)) ...',
1661     ** except that it does the right thing even if *tp + j would overflow.
1662     */
1663     if (! (j < 0
1664            ? (TYPE_SIGNED(time_t) ? time_t_min - j <= *tp : -1 - j < *tp)
1665            : *tp <= time_t_max - j))
1666         return TRUE;
1667     *tp += j;
1668     return FALSE;
1669 }
1670 
1671 static int
normalize_overflow(int * const tensptr,int * const unitsptr,const int base)1672 normalize_overflow(int *const tensptr, int *const unitsptr, const int base)
1673 {
1674     register int tensdelta;
1675 
1676     tensdelta = (*unitsptr >= 0) ?
1677         (*unitsptr / base) :
1678         (-1 - (-1 - *unitsptr) / base);
1679     *unitsptr -= tensdelta * base;
1680     return increment_overflow(tensptr, tensdelta);
1681 }
1682 
1683 static int
normalize_overflow32(int_fast32_t * const tensptr,int * const unitsptr,const int base)1684 normalize_overflow32(int_fast32_t *const tensptr, int *const unitsptr,
1685              const int base)
1686 {
1687     register int tensdelta;
1688 
1689     tensdelta = (*unitsptr >= 0) ?
1690         (*unitsptr / base) :
1691         (-1 - (-1 - *unitsptr) / base);
1692     *unitsptr -= tensdelta * base;
1693     return increment_overflow32(tensptr, tensdelta);
1694 }
1695 
1696 static int
tmcomp(register const struct tm * const atmp,register const struct tm * const btmp)1697 tmcomp(register const struct tm * const atmp,
1698        register const struct tm * const btmp)
1699 {
1700     register int result;
1701 
1702     if (atmp->tm_year != btmp->tm_year)
1703         return atmp->tm_year < btmp->tm_year ? -1 : 1;
1704     if ((result = (atmp->tm_mon - btmp->tm_mon)) == 0 &&
1705         (result = (atmp->tm_mday - btmp->tm_mday)) == 0 &&
1706         (result = (atmp->tm_hour - btmp->tm_hour)) == 0 &&
1707         (result = (atmp->tm_min - btmp->tm_min)) == 0)
1708             result = atmp->tm_sec - btmp->tm_sec;
1709     return result;
1710 }
1711 
1712 static time_t
time2sub(struct tm * const tmp,struct tm * (* const funcp)(const time_t *,int_fast32_t,struct tm *,struct state *),const int_fast32_t offset,int * const okayp,const int do_norm_secs,struct state * sp)1713 time2sub(struct tm * const tmp,
1714          struct tm *(*const funcp)(const time_t*, int_fast32_t, struct tm*, struct state*),
1715          const int_fast32_t offset,
1716          int * const okayp,
1717          const int do_norm_secs, struct state * sp) // android-changed: added sp
1718 {
1719     register int          dir;
1720     register int          i, j;
1721     register int          saved_seconds;
1722     register int_fast32_t li;
1723     register time_t       lo;
1724     register time_t       hi;
1725     int_fast32_t          y;
1726     time_t                newt;
1727     time_t                t;
1728     struct tm             yourtm, mytm;
1729 
1730     *okayp = FALSE;
1731     yourtm = *tmp;
1732     if (do_norm_secs) {
1733         if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec,
1734             SECSPERMIN))
1735                 return WRONG;
1736     }
1737     if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR))
1738         return WRONG;
1739     if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY))
1740         return WRONG;
1741     y = yourtm.tm_year;
1742     if (normalize_overflow32(&y, &yourtm.tm_mon, MONSPERYEAR))
1743         return WRONG;
1744     /*
1745     ** Turn y into an actual year number for now.
1746     ** It is converted back to an offset from TM_YEAR_BASE later.
1747     */
1748     if (increment_overflow32(&y, TM_YEAR_BASE))
1749         return WRONG;
1750     while (yourtm.tm_mday <= 0) {
1751         if (increment_overflow32(&y, -1))
1752             return WRONG;
1753         li = y + (1 < yourtm.tm_mon);
1754         yourtm.tm_mday += year_lengths[isleap(li)];
1755     }
1756     while (yourtm.tm_mday > DAYSPERLYEAR) {
1757         li = y + (1 < yourtm.tm_mon);
1758         yourtm.tm_mday -= year_lengths[isleap(li)];
1759         if (increment_overflow32(&y, 1))
1760             return WRONG;
1761     }
1762     for ( ; ; ) {
1763         i = mon_lengths[isleap(y)][yourtm.tm_mon];
1764         if (yourtm.tm_mday <= i)
1765             break;
1766         yourtm.tm_mday -= i;
1767         if (++yourtm.tm_mon >= MONSPERYEAR) {
1768             yourtm.tm_mon = 0;
1769             if (increment_overflow32(&y, 1))
1770                 return WRONG;
1771         }
1772     }
1773     if (increment_overflow32(&y, -TM_YEAR_BASE))
1774         return WRONG;
1775     yourtm.tm_year = y;
1776     if (yourtm.tm_year != y)
1777         return WRONG;
1778     if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN)
1779         saved_seconds = 0;
1780     else if (y + TM_YEAR_BASE < EPOCH_YEAR) {
1781         /*
1782         ** We can't set tm_sec to 0, because that might push the
1783         ** time below the minimum representable time.
1784         ** Set tm_sec to 59 instead.
1785         ** This assumes that the minimum representable time is
1786         ** not in the same minute that a leap second was deleted from,
1787         ** which is a safer assumption than using 58 would be.
1788         */
1789         if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN))
1790             return WRONG;
1791         saved_seconds = yourtm.tm_sec;
1792         yourtm.tm_sec = SECSPERMIN - 1;
1793     } else {
1794         saved_seconds = yourtm.tm_sec;
1795         yourtm.tm_sec = 0;
1796     }
1797     /*
1798     ** Do a binary search (this works whatever time_t's type is).
1799     */
1800     if (!TYPE_SIGNED(time_t)) {
1801         lo = 0;
1802         hi = lo - 1;
1803     } else {
1804         lo = 1;
1805         for (i = 0; i < (int) TYPE_BIT(time_t) - 1; ++i)
1806             lo *= 2;
1807         hi = -(lo + 1);
1808     }
1809     for ( ; ; ) {
1810         t = lo / 2 + hi / 2;
1811         if (t < lo)
1812             t = lo;
1813         else if (t > hi)
1814             t = hi;
1815         if ((*funcp)(&t, offset, &mytm, sp) == NULL) { // android-changed: added sp.
1816             /*
1817             ** Assume that t is too extreme to be represented in
1818             ** a struct tm; arrange things so that it is less
1819             ** extreme on the next pass.
1820             */
1821             dir = (t > 0) ? 1 : -1;
1822         } else  dir = tmcomp(&mytm, &yourtm);
1823         if (dir != 0) {
1824             if (t == lo) {
1825                 if (t == time_t_max)
1826                     return WRONG;
1827                 ++t;
1828                 ++lo;
1829             } else if (t == hi) {
1830                 if (t == time_t_min)
1831                     return WRONG;
1832                 --t;
1833                 --hi;
1834             }
1835             if (lo > hi)
1836                 return WRONG;
1837             if (dir > 0)
1838                 hi = t;
1839             else    lo = t;
1840             continue;
1841         }
1842         if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst)
1843             break;
1844         /*
1845         ** Right time, wrong type.
1846         ** Hunt for right time, right type.
1847         ** It's okay to guess wrong since the guess
1848         ** gets checked.
1849         */
1850         // BEGIN android-changed: support user-supplied sp
1851         if (sp == NULL) {
1852             sp = (struct state *)
1853                 ((funcp == localsub) ? lclptr : gmtptr);
1854         }
1855         // END android-changed
1856         if (sp == NULL)
1857             return WRONG;
1858         for (i = sp->typecnt - 1; i >= 0; --i) {
1859             if (sp->ttis[i].tt_isdst != yourtm.tm_isdst)
1860                 continue;
1861             for (j = sp->typecnt - 1; j >= 0; --j) {
1862                 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst)
1863                     continue;
1864                 newt = t + sp->ttis[j].tt_gmtoff -
1865                     sp->ttis[i].tt_gmtoff;
1866                 if ((*funcp)(&newt, offset, &mytm, sp) == NULL) // android-changed: added sp.
1867                     continue;
1868                 if (tmcomp(&mytm, &yourtm) != 0)
1869                     continue;
1870                 if (mytm.tm_isdst != yourtm.tm_isdst)
1871                     continue;
1872                 /*
1873                 ** We have a match.
1874                 */
1875                 t = newt;
1876                 goto label;
1877             }
1878         }
1879         return WRONG;
1880     }
1881 label:
1882     newt = t + saved_seconds;
1883     if ((newt < t) != (saved_seconds < 0))
1884         return WRONG;
1885     t = newt;
1886     if ((*funcp)(&t, offset, tmp, sp)) // android-changed: added sp.
1887         *okayp = TRUE;
1888     return t;
1889 }
1890 
1891 static time_t
time2(struct tm * const tmp,struct tm * (* const funcp)(const time_t *,int_fast32_t,struct tm *,struct state *),const int_fast32_t offset,int * const okayp,struct state * sp)1892 time2(struct tm * const tmp,
1893       struct tm * (*const funcp)(const time_t *, int_fast32_t, struct tm *, struct state *), // android-changed: added sp.
1894       const int_fast32_t offset,
1895       int *const okayp, struct state* sp) // android-changed: added sp.
1896 {
1897     time_t t;
1898 
1899     /*
1900     ** First try without normalization of seconds
1901     ** (in case tm_sec contains a value associated with a leap second).
1902     ** If that fails, try with normalization of seconds.
1903     */
1904     t = time2sub(tmp, funcp, offset, okayp, FALSE, sp);
1905     return *okayp ? t : time2sub(tmp, funcp, offset, okayp, TRUE, sp);
1906 }
1907 
1908 static time_t
time1(struct tm * const tmp,struct tm * (* const funcp)(const time_t *,int_fast32_t,struct tm *,struct state *),const int_fast32_t offset,struct state * sp)1909 time1(struct tm * const tmp,
1910       struct tm * (* const funcp) (const time_t *, int_fast32_t, struct tm *, struct state *), // android-changed: added sp.
1911       const int_fast32_t offset, struct state * sp) // android-changed: added sp.
1912 {
1913     register time_t t;
1914     register int    samei, otheri;
1915     register int    sameind, otherind;
1916     register int    i;
1917     register int    nseen;
1918     char            seen[TZ_MAX_TYPES];
1919     unsigned char   types[TZ_MAX_TYPES];
1920     int             okay;
1921 
1922     if (tmp == NULL) {
1923         errno = EINVAL;
1924         return WRONG;
1925     }
1926     if (tmp->tm_isdst > 1)
1927         tmp->tm_isdst = 1;
1928     t = time2(tmp, funcp, offset, &okay, sp); // android-changed: added sp.
1929     if (okay)
1930         return t;
1931     if (tmp->tm_isdst < 0)
1932 #ifdef PCTS
1933         /*
1934         ** POSIX Conformance Test Suite code courtesy Grant Sullivan.
1935         */
1936         tmp->tm_isdst = 0;  /* reset to std and try again */
1937 #else
1938         return t;
1939 #endif /* !defined PCTS */
1940     /*
1941     ** We're supposed to assume that somebody took a time of one type
1942     ** and did some math on it that yielded a "struct tm" that's bad.
1943     ** We try to divine the type they started from and adjust to the
1944     ** type they need.
1945     */
1946     // BEGIN android-changed: support user-supplied sp.
1947     if (sp == NULL) {
1948         sp = (struct state *) ((funcp == localsub) ?  lclptr : gmtptr);
1949     }
1950     // BEGIN android-changed
1951     if (sp == NULL)
1952         return WRONG;
1953     for (i = 0; i < sp->typecnt; ++i)
1954         seen[i] = FALSE;
1955     nseen = 0;
1956     for (i = sp->timecnt - 1; i >= 0; --i)
1957         if (!seen[sp->types[i]]) {
1958             seen[sp->types[i]] = TRUE;
1959             types[nseen++] = sp->types[i];
1960         }
1961     for (sameind = 0; sameind < nseen; ++sameind) {
1962         samei = types[sameind];
1963         if (sp->ttis[samei].tt_isdst != tmp->tm_isdst)
1964             continue;
1965         for (otherind = 0; otherind < nseen; ++otherind) {
1966             otheri = types[otherind];
1967             if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst)
1968                 continue;
1969             tmp->tm_sec += sp->ttis[otheri].tt_gmtoff -
1970                     sp->ttis[samei].tt_gmtoff;
1971             tmp->tm_isdst = !tmp->tm_isdst;
1972             t = time2(tmp, funcp, offset, &okay, sp); // android-changed: added sp.
1973             if (okay)
1974                 return t;
1975             tmp->tm_sec -= sp->ttis[otheri].tt_gmtoff -
1976                     sp->ttis[samei].tt_gmtoff;
1977             tmp->tm_isdst = !tmp->tm_isdst;
1978         }
1979     }
1980     return WRONG;
1981 }
1982 
1983 time_t
mktime(struct tm * const tmp)1984 mktime(struct tm * const tmp)
1985 {
1986     _tzLock();
1987     tzset_locked();
1988     time_t result = time1(tmp, localsub, 0L, NULL); // android-changed: extra parameter.
1989     _tzUnlock();
1990     return result;
1991 }
1992 
1993 #ifdef STD_INSPIRED
1994 
1995 time_t
timelocal(struct tm * const tmp)1996 timelocal(struct tm * const tmp)
1997 {
1998     if (tmp != NULL)
1999         tmp->tm_isdst = -1; /* in case it wasn't initialized */
2000     return mktime(tmp);
2001 }
2002 
2003 time_t
timegm(struct tm * const tmp)2004 timegm(struct tm * const tmp)
2005 {
2006     time_t result;
2007 
2008     if (tmp != NULL)
2009         tmp->tm_isdst = 0;
2010     _tzLock();
2011     result = time1(tmp, gmtsub, 0L, NULL); // android-changed: extra parameter.
2012     _tzUnlock();
2013 
2014     return result;
2015 }
2016 
2017 time_t
timeoff(struct tm * const tmp,const long offset)2018 timeoff(struct tm *const tmp, const long offset)
2019 {
2020     if (tmp != NULL)
2021         tmp->tm_isdst = 0;
2022     return time1(tmp, gmtsub, offset, NULL); // android-changed: extra parameter.
2023 }
2024 
2025 #endif /* defined STD_INSPIRED */
2026 
2027 #ifdef CMUCS
2028 
2029 /*
2030 ** The following is supplied for compatibility with
2031 ** previous versions of the CMUCS runtime library.
2032 */
2033 
2034 long
gtime(struct tm * const tmp)2035 gtime(struct tm * const tmp)
2036 {
2037     const time_t t = mktime(tmp);
2038 
2039     if (t == WRONG)
2040         return -1;
2041     return t;
2042 }
2043 
2044 #endif /* defined CMUCS */
2045 
2046 /*
2047 ** XXX--is the below the right way to conditionalize??
2048 */
2049 
2050 #ifdef STD_INSPIRED
2051 
2052 /*
2053 ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599
2054 ** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which
2055 ** is not the case if we are accounting for leap seconds.
2056 ** So, we provide the following conversion routines for use
2057 ** when exchanging timestamps with POSIX conforming systems.
2058 */
2059 
2060 static int_fast64_t
leapcorr(time_t * timep)2061 leapcorr(time_t * timep)
2062 {
2063     register struct state *  sp;
2064     register struct lsinfo * lp;
2065     register int             i;
2066 
2067     sp = lclptr;
2068     i = sp->leapcnt;
2069     while (--i >= 0) {
2070         lp = &sp->lsis[i];
2071         if (*timep >= lp->ls_trans)
2072             return lp->ls_corr;
2073     }
2074     return 0;
2075 }
2076 
2077 time_t
time2posix(time_t t)2078 time2posix(time_t t)
2079 {
2080     tzset();
2081     return t - leapcorr(&t);
2082 }
2083 
2084 time_t
posix2time(time_t t)2085 posix2time(time_t t)
2086 {
2087     time_t x;
2088     time_t y;
2089 
2090     tzset();
2091     /*
2092     ** For a positive leap second hit, the result
2093     ** is not unique. For a negative leap second
2094     ** hit, the corresponding time doesn't exist,
2095     ** so we return an adjacent second.
2096     */
2097     x = t + leapcorr(&t);
2098     y = x - leapcorr(&x);
2099     if (y < t) {
2100         do {
2101             x++;
2102             y = x - leapcorr(&x);
2103         } while (y < t);
2104         if (t != y)
2105             return x - 1;
2106     } else if (y > t) {
2107         do {
2108             --x;
2109             y = x - leapcorr(&x);
2110         } while (y > t);
2111         if (t != y)
2112             return x + 1;
2113     }
2114     return x;
2115 }
2116 
2117 #endif /* defined STD_INSPIRED */
2118 
2119 // BEGIN android-added
2120 
2121 #include <assert.h>
2122 #include <stdint.h>
2123 #include <arpa/inet.h> // For ntohl(3).
2124 
__bionic_open_tzdata_path(const char * path_prefix_variable,const char * path_suffix,const char * olson_id,int * data_size)2125 static int __bionic_open_tzdata_path(const char* path_prefix_variable, const char* path_suffix,
2126                                      const char* olson_id, int* data_size) {
2127   const char* path_prefix = getenv(path_prefix_variable);
2128   if (path_prefix == NULL) {
2129     fprintf(stderr, "%s: %s not set!\n", __FUNCTION__, path_prefix_variable);
2130     return -1;
2131   }
2132   size_t path_length = strlen(path_prefix) + 1 + strlen(path_suffix) + 1;
2133   char* path = malloc(path_length);
2134   if (path == NULL) {
2135     fprintf(stderr, "%s: couldn't allocate %zu-byte path\n", __FUNCTION__, path_length);
2136     return -1;
2137   }
2138   snprintf(path, path_length, "%s/%s", path_prefix, path_suffix);
2139   int fd = TEMP_FAILURE_RETRY(open(path, OPEN_MODE));
2140   if (fd == -1) {
2141     XLOG(("%s: could not open \"%s\": %s\n", __FUNCTION__, path, strerror(errno)));
2142     free(path);
2143     return -2; // Distinguish failure to find any data from failure to find a specific id.
2144   }
2145 
2146   // byte[12] tzdata_version  -- "tzdata2012f\0"
2147   // int index_offset
2148   // int data_offset
2149   // int zonetab_offset
2150   struct bionic_tzdata_header {
2151     char tzdata_version[12];
2152     int32_t index_offset;
2153     int32_t data_offset;
2154     int32_t zonetab_offset;
2155   } header;
2156   memset(&header, 0, sizeof(header));
2157   ssize_t bytes_read = TEMP_FAILURE_RETRY(read(fd, &header, sizeof(header)));
2158   if (bytes_read != sizeof(header)) {
2159     fprintf(stderr, "%s: could not read header of \"%s\": %s\n",
2160             __FUNCTION__, path, (bytes_read == -1) ? strerror(errno) : "short read");
2161     free(path);
2162     close(fd);
2163     return -1;
2164   }
2165 
2166   if (strncmp(header.tzdata_version, "tzdata", 6) != 0 || header.tzdata_version[11] != 0) {
2167     fprintf(stderr, "%s: bad magic in \"%s\": \"%.6s\"\n",
2168             __FUNCTION__, path, header.tzdata_version);
2169     free(path);
2170     close(fd);
2171     return -1;
2172   }
2173 
2174 #if 0
2175   fprintf(stderr, "version: %s\n", header.tzdata_version);
2176   fprintf(stderr, "index_offset = %d\n", ntohl(header.index_offset));
2177   fprintf(stderr, "data_offset = %d\n", ntohl(header.data_offset));
2178   fprintf(stderr, "zonetab_offset = %d\n", ntohl(header.zonetab_offset));
2179 #endif
2180 
2181   if (TEMP_FAILURE_RETRY(lseek(fd, ntohl(header.index_offset), SEEK_SET)) == -1) {
2182     fprintf(stderr, "%s: couldn't seek to index in \"%s\": %s\n",
2183             __FUNCTION__, path, strerror(errno));
2184     free(path);
2185     close(fd);
2186     return -1;
2187   }
2188 
2189   off_t specific_zone_offset = -1;
2190   ssize_t index_size = ntohl(header.data_offset) - ntohl(header.index_offset);
2191   char* index = malloc(index_size);
2192   if (index == NULL) {
2193     fprintf(stderr, "%s: couldn't allocate %zd-byte index for \"%s\"\n",
2194             __FUNCTION__, index_size, path);
2195     free(path);
2196     close(fd);
2197     return -1;
2198   }
2199   if (TEMP_FAILURE_RETRY(read(fd, index, index_size)) != index_size) {
2200     fprintf(stderr, "%s: could not read index of \"%s\": %s\n",
2201             __FUNCTION__, path, (bytes_read == -1) ? strerror(errno) : "short read");
2202     free(path);
2203     free(index);
2204     close(fd);
2205     return -1;
2206   }
2207 
2208   static const size_t NAME_LENGTH = 40;
2209   struct index_entry_t {
2210     char buf[NAME_LENGTH];
2211     int32_t start;
2212     int32_t length;
2213     int32_t unused; // Was raw GMT offset; always 0 since tzdata2014f (L).
2214   };
2215 
2216   size_t id_count = (ntohl(header.data_offset) - ntohl(header.index_offset)) / sizeof(struct index_entry_t);
2217   struct index_entry_t* entry = (struct index_entry_t*) index;
2218   for (size_t i = 0; i < id_count; ++i) {
2219     char this_id[NAME_LENGTH + 1];
2220     memcpy(this_id, entry->buf, NAME_LENGTH);
2221     this_id[NAME_LENGTH] = '\0';
2222 
2223     if (strcmp(this_id, olson_id) == 0) {
2224       specific_zone_offset = ntohl(entry->start) + ntohl(header.data_offset);
2225       *data_size = ntohl(entry->length);
2226       break;
2227     }
2228 
2229     ++entry;
2230   }
2231   free(index);
2232 
2233   if (specific_zone_offset == -1) {
2234     XLOG(("%s: couldn't find zone \"%s\"\n", __FUNCTION__, olson_id));
2235     free(path);
2236     close(fd);
2237     return -1;
2238   }
2239 
2240   if (TEMP_FAILURE_RETRY(lseek(fd, specific_zone_offset, SEEK_SET)) == -1) {
2241     fprintf(stderr, "%s: could not seek to %ld in \"%s\": %s\n",
2242             __FUNCTION__, specific_zone_offset, path, strerror(errno));
2243     free(path);
2244     close(fd);
2245     return -1;
2246   }
2247 
2248   // TODO: check that there's TZ_MAGIC at this offset, so we can fall back to the other file if not.
2249 
2250   free(path);
2251   return fd;
2252 }
2253 
__bionic_open_tzdata(const char * olson_id,int * data_size)2254 static int __bionic_open_tzdata(const char* olson_id, int* data_size) {
2255   int fd = __bionic_open_tzdata_path("ANDROID_ROOT", "/usr/share/zoneinfo/tzdata", olson_id, data_size);
2256   if (fd == -2) {
2257     // The first thing that 'recovery' does is try to format the current time. It doesn't have
2258     // any tzdata available, so we must not abort here --- doing so breaks the recovery image!
2259     fprintf(stderr, "%s: couldn't find any tzdata when looking for %s!\n", __FUNCTION__, olson_id);
2260   }
2261   return fd;
2262 }
2263 
2264 // Caches the most recent timezone (http://b/8270865).
__bionic_tzload_cached(const char * name,struct state * const sp,const int doextend)2265 static int __bionic_tzload_cached(const char* name, struct state* const sp, const int doextend) {
2266   _tzLock();
2267 
2268   // Our single-item cache.
2269   static char* g_cached_time_zone_name;
2270   static struct state g_cached_time_zone;
2271 
2272   // Do we already have this timezone cached?
2273   if (g_cached_time_zone_name != NULL && strcmp(name, g_cached_time_zone_name) == 0) {
2274     *sp = g_cached_time_zone;
2275     _tzUnlock();
2276     return 0;
2277   }
2278 
2279   // Can we load it?
2280   int rc = tzload(name, sp, doextend);
2281   if (rc == 0) {
2282     // Update the cache.
2283     free(g_cached_time_zone_name);
2284     g_cached_time_zone_name = strdup(name);
2285     g_cached_time_zone = *sp;
2286   }
2287 
2288   _tzUnlock();
2289   return rc;
2290 }
2291 
2292 // Non-standard API: mktime(3) but with an explicit timezone parameter.
2293 // This can't actually be hidden/removed until we fix MtpUtils.cpp
mktime_tz(struct tm * const tmp,const char * tz)2294 __attribute__((visibility("default"))) time_t mktime_tz(struct tm* const tmp, const char* tz) {
2295   struct state* st = malloc(sizeof(*st));
2296   time_t return_value;
2297 
2298   if (st == NULL)
2299     return 0;
2300   if (__bionic_tzload_cached(tz, st, TRUE) != 0) {
2301     // TODO: not sure what's best here, but for now, we fall back to gmt.
2302     gmtload(st);
2303   }
2304 
2305   return_value = time1(tmp, localsub, 0L, st);
2306   free(st);
2307   return return_value;
2308 }
2309 
2310 // END android-added
2311