/* $NetBSD: localtime.c,v 1.78 2013/09/20 19:06:54 christos Exp $ */ /* ** This file is in the public domain, so clarified as of ** 1996-06-05 by Arthur David Olson. */ #include #if defined(LIBC_SCCS) && !defined(lint) #if 0 static char elsieid[] = "@(#)localtime.c 8.17"; #else __RCSID("$NetBSD: localtime.c,v 1.78 2013/09/20 19:06:54 christos Exp $"); #endif #endif /* LIBC_SCCS and not lint */ /* ** Leap second handling from Bradley White. ** POSIX-style TZ environment variable handling from Guy Harris. */ /*LINTLIBRARY*/ #include "namespace.h" #include #include "private.h" #include "tzfile.h" #include "fcntl.h" #include "reentrant.h" #if defined(__weak_alias) __weak_alias(daylight,_daylight) __weak_alias(tzname,_tzname) #endif #ifndef TZ_ABBR_MAX_LEN #define TZ_ABBR_MAX_LEN 16 #endif /* !defined TZ_ABBR_MAX_LEN */ #ifndef TZ_ABBR_CHAR_SET #define TZ_ABBR_CHAR_SET \ "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 :+-._" #endif /* !defined TZ_ABBR_CHAR_SET */ #ifndef TZ_ABBR_ERR_CHAR #define TZ_ABBR_ERR_CHAR '_' #endif /* !defined TZ_ABBR_ERR_CHAR */ /* ** SunOS 4.1.1 headers lack O_BINARY. */ #ifdef O_BINARY #define OPEN_MODE (O_RDONLY | O_BINARY) #endif /* defined O_BINARY */ #ifndef O_BINARY #define OPEN_MODE O_RDONLY #endif /* !defined O_BINARY */ #ifndef WILDABBR /* ** Someone might make incorrect use of a time zone abbreviation: ** 1. They might reference tzname[0] before calling tzset (explicitly ** or implicitly). ** 2. They might reference tzname[1] before calling tzset (explicitly ** or implicitly). ** 3. They might reference tzname[1] after setting to a time zone ** in which Daylight Saving Time is never observed. ** 4. They might reference tzname[0] after setting to a time zone ** in which Standard Time is never observed. ** 5. They might reference tm.TM_ZONE after calling offtime. ** What's best to do in the above cases is open to debate; ** for now, we just set things up so that in any of the five cases ** WILDABBR is used. Another possibility: initialize tzname[0] to the ** string "tzname[0] used before set", and similarly for the other cases. ** And another: initialize tzname[0] to "ERA", with an explanation in the ** manual page of what this "time zone abbreviation" means (doing this so ** that tzname[0] has the "normal" length of three characters). */ #define WILDABBR " " #endif /* !defined WILDABBR */ static const char wildabbr[] = WILDABBR; static const char gmt[] = "GMT"; /* ** The DST rules to use if TZ has no rules and we can't load TZDEFRULES. ** We default to US rules as of 1999-08-17. ** POSIX 1003.1 section 8.1.1 says that the default DST rules are ** implementation dependent; for historical reasons, US rules are a ** common default. */ #ifndef TZDEFRULESTRING #define TZDEFRULESTRING ",M4.1.0,M10.5.0" #endif /* !defined TZDEFDST */ struct ttinfo { /* time type information */ int_fast32_t tt_gmtoff; /* UT offset in seconds */ int tt_isdst; /* used to set tm_isdst */ int tt_abbrind; /* abbreviation list index */ int tt_ttisstd; /* TRUE if transition is std time */ int tt_ttisgmt; /* TRUE if transition is UT */ }; struct lsinfo { /* leap second information */ time_t ls_trans; /* transition time */ int_fast64_t ls_corr; /* correction to apply */ }; #define BIGGEST(a, b) (((a) > (b)) ? (a) : (b)) #ifdef TZNAME_MAX #define MY_TZNAME_MAX TZNAME_MAX #endif /* defined TZNAME_MAX */ #ifndef TZNAME_MAX #define MY_TZNAME_MAX 255 #endif /* !defined TZNAME_MAX */ struct __state { int leapcnt; int timecnt; int typecnt; int charcnt; int goback; int goahead; time_t ats[TZ_MAX_TIMES]; unsigned char types[TZ_MAX_TIMES]; struct ttinfo ttis[TZ_MAX_TYPES]; char chars[/*CONSTCOND*/BIGGEST(BIGGEST(TZ_MAX_CHARS + 1, sizeof gmt), (2 * (MY_TZNAME_MAX + 1)))]; struct lsinfo lsis[TZ_MAX_LEAPS]; int defaulttype; /* for early times or if no transitions */ }; struct rule { int r_type; /* type of rule--see below */ int r_day; /* day number of rule */ int r_week; /* week number of rule */ int r_mon; /* month number of rule */ int_fast32_t r_time; /* transition time of rule */ }; #define JULIAN_DAY 0 /* Jn - Julian day */ #define DAY_OF_YEAR 1 /* n - day of year */ #define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */ typedef struct tm *(*subfun_t)(const timezone_t sp, const time_t *timep, const int_fast32_t offset, struct tm *tmp); /* ** Prototypes for static functions. */ static int_fast32_t detzcode(const char * codep); static time_t detzcode64(const char * codep); static int differ_by_repeat(time_t t1, time_t t0); static const char * getzname(const char * strp) ATTRIBUTE_PURE; static const char * getqzname(const char * strp, const int delim) ATTRIBUTE_PURE; static const char * getnum(const char * strp, int * nump, int min, int max); static const char * getsecs(const char * strp, int_fast32_t * secsp); static const char * getoffset(const char * strp, int_fast32_t * offsetp); static const char * getrule(const char * strp, struct rule * rulep); static void gmtload(timezone_t sp); static struct tm * gmtsub(const timezone_t sp, const time_t *timep, const int_fast32_t offset, struct tm * tmp); static struct tm * localsub(const timezone_t sp, const time_t *timep, const int_fast32_t offset, struct tm *tmp); static int increment_overflow(int * number, int delta); static int increment_overflow32(int_fast32_t * number, int delta); static int leaps_thru_end_of(int y) ATTRIBUTE_PURE; static int normalize_overflow(int * tensptr, int * unitsptr, int base); static int normalize_overflow32(int_fast32_t * tensptr, int * unitsptr, int base); static void settzname(void); static time_t time1(const timezone_t sp, struct tm * const tmp, subfun_t funcp, const int_fast32_t offset); static time_t time2(const timezone_t sp, struct tm * const tmp, subfun_t funcp, const int_fast32_t offset, int *const okayp); static time_t time2sub(const timezone_t sp, struct tm * const tmp, subfun_t funcp, const int_fast32_t offset, int *const okayp, const int do_norm_secs); static struct tm * timesub(const timezone_t sp, const time_t * timep, const int_fast32_t offset, struct tm * tmp); static int tmcomp(const struct tm * atmp, const struct tm * btmp); static time_t transtime(time_t janfirst, int year, const struct rule * rulep, const int_fast32_t offset) ATTRIBUTE_PURE; static int typesequiv(const timezone_t sp, int a, int b); static int tzload(timezone_t sp, const char * name, int doextend); static int tzparse(timezone_t sp, const char * name, int lastditch); static void tzset_unlocked(void); static void tzsetwall_unlocked(void); static int_fast64_t leapcorr(const timezone_t sp, time_t * timep); static timezone_t lclptr; static timezone_t gmtptr; #ifndef TZ_STRLEN_MAX #define TZ_STRLEN_MAX 255 #endif /* !defined TZ_STRLEN_MAX */ static char lcl_TZname[TZ_STRLEN_MAX + 1]; static int lcl_is_set; static int gmt_is_set; #if !defined(__LIBC12_SOURCE__) __aconst char * tzname[2] = { (__aconst char *)__UNCONST(wildabbr), (__aconst char *)__UNCONST(wildabbr) }; #else extern __aconst char * tzname[2]; #endif #ifdef _REENTRANT static rwlock_t lcl_lock = RWLOCK_INITIALIZER; #endif /* ** Section 4.12.3 of X3.159-1989 requires that ** Except for the strftime function, these functions [asctime, ** ctime, gmtime, localtime] return values in one of two static ** objects: a broken-down time structure and an array of char. ** Thanks to Paul Eggert for noting this. */ static struct tm tm; #ifdef USG_COMPAT #if !defined(__LIBC12_SOURCE__) long timezone = 0; int daylight = 0; #else extern int daylight; extern long timezone __RENAME(__timezone13); #endif #endif /* defined USG_COMPAT */ #ifdef ALTZONE time_t altzone = 0; #endif /* defined ALTZONE */ static int_fast32_t detzcode(const char *const codep) { int_fast32_t result; int i; result = (codep[0] & 0x80) ? -1 : 0; for (i = 0; i < 4; ++i) result = (result << 8) | (codep[i] & 0xff); return result; } static time_t detzcode64(const char *const codep) { time_t result; int i; result = (time_t)((codep[0] & 0x80) ? (~(int_fast64_t) 0) : 0); for (i = 0; i < 8; ++i) result = result * 256 + (codep[i] & 0xff); return result; } const char * tzgetname(const timezone_t sp, int isdst) { int i; for (i = 0; i < sp->timecnt; ++i) { const struct ttinfo *const ttisp = &sp->ttis[sp->types[i]]; if (ttisp->tt_isdst == isdst) return &sp->chars[ttisp->tt_abbrind]; } return NULL; } static void settzname_z(timezone_t sp) { int i; /* ** Scrub the abbreviations. ** First, replace bogus characters. */ for (i = 0; i < sp->charcnt; ++i) if (strchr(TZ_ABBR_CHAR_SET, sp->chars[i]) == NULL) sp->chars[i] = TZ_ABBR_ERR_CHAR; /* ** Second, truncate long abbreviations. */ for (i = 0; i < sp->typecnt; ++i) { const struct ttinfo * const ttisp = &sp->ttis[i]; char * cp = &sp->chars[ttisp->tt_abbrind]; if (strlen(cp) > TZ_ABBR_MAX_LEN && strcmp(cp, GRANDPARENTED) != 0) *(cp + TZ_ABBR_MAX_LEN) = '\0'; } } static void settzname(void) { timezone_t const sp = lclptr; int i; tzname[0] = (__aconst char *)__UNCONST(wildabbr); tzname[1] = (__aconst char *)__UNCONST(wildabbr); #ifdef USG_COMPAT daylight = 0; timezone = 0; #endif /* defined USG_COMPAT */ #ifdef ALTZONE altzone = 0; #endif /* defined ALTZONE */ if (sp == NULL) { tzname[0] = tzname[1] = (__aconst char *)__UNCONST(gmt); return; } /* ** And to get the latest zone names into tzname. . . */ for (i = 0; i < sp->typecnt; ++i) { const struct ttinfo * const ttisp = &sp->ttis[i]; tzname[ttisp->tt_isdst] = &sp->chars[ttisp->tt_abbrind]; #ifdef USG_COMPAT if (ttisp->tt_isdst) daylight = 1; if (!ttisp->tt_isdst) timezone = -(ttisp->tt_gmtoff); #endif /* defined USG_COMPAT */ #ifdef ALTZONE if (ttisp->tt_isdst) altzone = -(ttisp->tt_gmtoff); #endif /* defined ALTZONE */ } settzname_z(sp); } static int differ_by_repeat(const time_t t1, const time_t t0) { if (TYPE_BIT(time_t) - TYPE_SIGNED(time_t) < SECSPERREPEAT_BITS) return 0; return (int_fast64_t)t1 - (int_fast64_t)t0 == SECSPERREPEAT; } static int tzload(timezone_t sp, const char *name, const int doextend) { const char * p; int i; int fid; int stored; ssize_t nread; typedef union { struct tzhead tzhead; char buf[2 * sizeof(struct tzhead) + 2 * sizeof *sp + 4 * TZ_MAX_TIMES]; } u_t; u_t * up; up = calloc(1, sizeof *up); if (up == NULL) return -1; sp->goback = sp->goahead = FALSE; if (name == NULL && (name = TZDEFAULT) == NULL) goto oops; { int doaccess; /* ** Section 4.9.1 of the C standard says that ** "FILENAME_MAX expands to an integral constant expression ** that is the size needed for an array of char large enough ** to hold the longest file name string that the implementation ** guarantees can be opened." */ char fullname[FILENAME_MAX + 1]; if (name[0] == ':') ++name; doaccess = name[0] == '/'; if (!doaccess) { if ((p = TZDIR) == NULL) goto oops; if ((strlen(p) + strlen(name) + 1) >= sizeof fullname) goto oops; (void) strcpy(fullname, p); /* XXX strcpy is safe */ (void) strcat(fullname, "/"); /* XXX strcat is safe */ (void) strcat(fullname, name); /* XXX strcat is safe */ /* ** Set doaccess if '.' (as in "../") shows up in name. */ if (strchr(name, '.') != NULL) doaccess = TRUE; name = fullname; } if (doaccess && access(name, R_OK) != 0) goto oops; /* * XXX potential security problem here if user of a set-id * program has set TZ (which is passed in as name) here, * and uses a race condition trick to defeat the access(2) * above. */ if ((fid = open(name, OPEN_MODE)) == -1) goto oops; } nread = read(fid, up->buf, sizeof up->buf); if (close(fid) < 0 || nread <= 0) goto oops; for (stored = 4; stored <= 8; stored *= 2) { int ttisstdcnt; int ttisgmtcnt; ttisstdcnt = (int) detzcode(up->tzhead.tzh_ttisstdcnt); ttisgmtcnt = (int) detzcode(up->tzhead.tzh_ttisgmtcnt); sp->leapcnt = (int) detzcode(up->tzhead.tzh_leapcnt); sp->timecnt = (int) detzcode(up->tzhead.tzh_timecnt); sp->typecnt = (int) detzcode(up->tzhead.tzh_typecnt); sp->charcnt = (int) detzcode(up->tzhead.tzh_charcnt); p = up->tzhead.tzh_charcnt + sizeof up->tzhead.tzh_charcnt; if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS || sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES || sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES || sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS || (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) || (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0)) goto oops; if (nread - (p - up->buf) < sp->timecnt * stored + /* ats */ sp->timecnt + /* types */ sp->typecnt * 6 + /* ttinfos */ sp->charcnt + /* chars */ sp->leapcnt * (stored + 4) + /* lsinfos */ ttisstdcnt + /* ttisstds */ ttisgmtcnt) /* ttisgmts */ goto oops; for (i = 0; i < sp->timecnt; ++i) { sp->ats[i] = (time_t)((stored == 4) ? detzcode(p) : detzcode64(p)); p += stored; } for (i = 0; i < sp->timecnt; ++i) { sp->types[i] = (unsigned char) *p++; if (sp->types[i] >= sp->typecnt) goto oops; } for (i = 0; i < sp->typecnt; ++i) { struct ttinfo * ttisp; ttisp = &sp->ttis[i]; ttisp->tt_gmtoff = detzcode(p); p += 4; ttisp->tt_isdst = (unsigned char) *p++; if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1) goto oops; ttisp->tt_abbrind = (unsigned char) *p++; if (ttisp->tt_abbrind < 0 || ttisp->tt_abbrind > sp->charcnt) goto oops; } for (i = 0; i < sp->charcnt; ++i) sp->chars[i] = *p++; sp->chars[i] = '\0'; /* ensure '\0' at end */ for (i = 0; i < sp->leapcnt; ++i) { struct lsinfo * lsisp; lsisp = &sp->lsis[i]; lsisp->ls_trans = (time_t)((stored == 4) ? detzcode(p) : detzcode64(p)); p += stored; lsisp->ls_corr = detzcode(p); p += 4; } for (i = 0; i < sp->typecnt; ++i) { struct ttinfo * ttisp; ttisp = &sp->ttis[i]; if (ttisstdcnt == 0) ttisp->tt_ttisstd = FALSE; else { ttisp->tt_ttisstd = *p++; if (ttisp->tt_ttisstd != TRUE && ttisp->tt_ttisstd != FALSE) goto oops; } } for (i = 0; i < sp->typecnt; ++i) { struct ttinfo * ttisp; ttisp = &sp->ttis[i]; if (ttisgmtcnt == 0) ttisp->tt_ttisgmt = FALSE; else { ttisp->tt_ttisgmt = *p++; if (ttisp->tt_ttisgmt != TRUE && ttisp->tt_ttisgmt != FALSE) goto oops; } } /* ** Out-of-sort ats should mean we're running on a ** signed time_t system but using a data file with ** unsigned values (or vice versa). */ for (i = 0; i < sp->timecnt; ++i) if ((i < sp->timecnt - 1 && sp->ats[i] > sp->ats[i + 1]) || (i == sp->timecnt - 1 && !TYPE_SIGNED(time_t) && sp->ats[i] > ((stored == 4) ? INT32_MAX : INT64_MAX))) { if (TYPE_SIGNED(time_t)) { /* ** Ignore the end (easy). */ sp->timecnt = i + 1; } else { /* ** Ignore the beginning (harder). */ int j; /* ** Keep the record right before the ** epoch boundary, ** but tweak it so that it starts ** right with the epoch ** (thanks to Doug Bailey). */ sp->ats[i] = 0; for (j = 0; j + i < sp->timecnt; ++j) { sp->ats[j] = sp->ats[j + i]; sp->types[j] = sp->types[j + i]; } sp->timecnt = j; } break; } /* ** If this is an old file, we're done. */ if (up->tzhead.tzh_version[0] == '\0') break; nread -= p - up->buf; for (i = 0; i < nread; ++i) up->buf[i] = p[i]; /* ** If this is a narrow time_t system, we're done. */ if (stored >= (int) sizeof(time_t)) break; } if (doextend && nread > 2 && up->buf[0] == '\n' && up->buf[nread - 1] == '\n' && sp->typecnt + 2 <= TZ_MAX_TYPES) { struct __state ts; int result; up->buf[nread - 1] = '\0'; result = tzparse(&ts, &up->buf[1], FALSE); if (result == 0 && ts.typecnt == 2 && sp->charcnt + ts.charcnt <= TZ_MAX_CHARS) { for (i = 0; i < 2; ++i) ts.ttis[i].tt_abbrind += sp->charcnt; for (i = 0; i < ts.charcnt; ++i) sp->chars[sp->charcnt++] = ts.chars[i]; i = 0; while (i < ts.timecnt && ts.ats[i] <= sp->ats[sp->timecnt - 1]) ++i; while (i < ts.timecnt && sp->timecnt < TZ_MAX_TIMES) { sp->ats[sp->timecnt] = ts.ats[i]; sp->types[sp->timecnt] = sp->typecnt + ts.types[i]; ++sp->timecnt; ++i; } sp->ttis[sp->typecnt++] = ts.ttis[0]; sp->ttis[sp->typecnt++] = ts.ttis[1]; } } if (sp->timecnt > 1) { for (i = 1; i < sp->timecnt; ++i) if (typesequiv(sp, sp->types[i], sp->types[0]) && differ_by_repeat(sp->ats[i], sp->ats[0])) { sp->goback = TRUE; break; } for (i = sp->timecnt - 2; i >= 0; --i) if (typesequiv(sp, sp->types[sp->timecnt - 1], sp->types[i]) && differ_by_repeat(sp->ats[sp->timecnt - 1], sp->ats[i])) { sp->goahead = TRUE; break; } } /* ** If type 0 is is unused in transitions, ** it's the type to use for early times. */ for (i = 0; i < sp->typecnt; ++i) if (sp->types[i] == 0) break; i = (i >= sp->typecnt) ? 0 : -1; /* ** Absent the above, ** if there are transition times ** and the first transition is to a daylight time ** find the standard type less than and closest to ** the type of the first transition. */ if (i < 0 && sp->timecnt > 0 && sp->ttis[sp->types[0]].tt_isdst) { i = sp->types[0]; while (--i >= 0) if (!sp->ttis[i].tt_isdst) break; } /* ** If no result yet, find the first standard type. ** If there is none, punt to type zero. */ if (i < 0) { i = 0; while (sp->ttis[i].tt_isdst) if (++i >= sp->typecnt) { i = 0; break; } } sp->defaulttype = i; free(up); return 0; oops: free(up); return -1; } static int typesequiv(const timezone_t sp, const int a, const int b) { int result; if (sp == NULL || a < 0 || a >= sp->typecnt || b < 0 || b >= sp->typecnt) result = FALSE; else { const struct ttinfo * ap = &sp->ttis[a]; const struct ttinfo * bp = &sp->ttis[b]; result = ap->tt_gmtoff == bp->tt_gmtoff && ap->tt_isdst == bp->tt_isdst && ap->tt_ttisstd == bp->tt_ttisstd && ap->tt_ttisgmt == bp->tt_ttisgmt && strcmp(&sp->chars[ap->tt_abbrind], &sp->chars[bp->tt_abbrind]) == 0; } return result; } static const int mon_lengths[2][MONSPERYEAR] = { { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } }; static const int year_lengths[2] = { DAYSPERNYEAR, DAYSPERLYEAR }; /* ** Given a pointer into a time zone string, scan until a character that is not ** a valid character in a zone name is found. Return a pointer to that ** character. */ static const char * getzname(const char *strp) { char c; while ((c = *strp) != '\0' && !is_digit(c) && c != ',' && c != '-' && c != '+') ++strp; return strp; } /* ** Given a pointer into an extended time zone string, scan until the ending ** delimiter of the zone name is located. Return a pointer to the delimiter. ** ** As with getzname above, the legal character set is actually quite ** restricted, with other characters producing undefined results. ** We don't do any checking here; checking is done later in common-case code. */ static const char * getqzname(const char *strp, const int delim) { int c; while ((c = *strp) != '\0' && c != delim) ++strp; return strp; } /* ** Given a pointer into a time zone string, extract a number from that string. ** Check that the number is within a specified range; if it is not, return ** NULL. ** Otherwise, return a pointer to the first character not part of the number. */ static const char * getnum(const char *strp, int *const nump, const int min, const int max) { char c; int num; if (strp == NULL || !is_digit(c = *strp)) { errno = EINVAL; return NULL; } num = 0; do { num = num * 10 + (c - '0'); if (num > max) { errno = EOVERFLOW; return NULL; /* illegal value */ } c = *++strp; } while (is_digit(c)); if (num < min) { errno = EINVAL; return NULL; /* illegal value */ } *nump = num; return strp; } /* ** Given a pointer into a time zone string, extract a number of seconds, ** in hh[:mm[:ss]] form, from the string. ** If any error occurs, return NULL. ** Otherwise, return a pointer to the first character not part of the number ** of seconds. */ static const char * getsecs(const char *strp, int_fast32_t *const secsp) { int num; /* ** `HOURSPERDAY * DAYSPERWEEK - 1' allows quasi-Posix rules like ** "M10.4.6/26", which does not conform to Posix, ** but which specifies the equivalent of ** ``02:00 on the first Sunday on or after 23 Oct''. */ strp = getnum(strp, &num, 0, HOURSPERDAY * DAYSPERWEEK - 1); if (strp == NULL) return NULL; *secsp = num * (int_fast32_t) SECSPERHOUR; if (*strp == ':') { ++strp; strp = getnum(strp, &num, 0, MINSPERHOUR - 1); if (strp == NULL) return NULL; *secsp += num * SECSPERMIN; if (*strp == ':') { ++strp; /* `SECSPERMIN' allows for leap seconds. */ strp = getnum(strp, &num, 0, SECSPERMIN); if (strp == NULL) return NULL; *secsp += num; } } return strp; } /* ** Given a pointer into a time zone string, extract an offset, in ** [+-]hh[:mm[:ss]] form, from the string. ** If any error occurs, return NULL. ** Otherwise, return a pointer to the first character not part of the time. */ static const char * getoffset(const char *strp, int_fast32_t *const offsetp) { int neg = 0; if (*strp == '-') { neg = 1; ++strp; } else if (*strp == '+') ++strp; strp = getsecs(strp, offsetp); if (strp == NULL) return NULL; /* illegal time */ if (neg) *offsetp = -*offsetp; return strp; } /* ** Given a pointer into a time zone string, extract a rule in the form ** date[/time]. See POSIX section 8 for the format of "date" and "time". ** If a valid rule is not found, return NULL. ** Otherwise, return a pointer to the first character not part of the rule. */ static const char * getrule(const char *strp, struct rule *const rulep) { if (*strp == 'J') { /* ** Julian day. */ rulep->r_type = JULIAN_DAY; ++strp; strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR); } else if (*strp == 'M') { /* ** Month, week, day. */ rulep->r_type = MONTH_NTH_DAY_OF_WEEK; ++strp; strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR); if (strp == NULL) return NULL; if (*strp++ != '.') return NULL; strp = getnum(strp, &rulep->r_week, 1, 5); if (strp == NULL) return NULL; if (*strp++ != '.') return NULL; strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1); } else if (is_digit(*strp)) { /* ** Day of year. */ rulep->r_type = DAY_OF_YEAR; strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1); } else return NULL; /* invalid format */ if (strp == NULL) return NULL; if (*strp == '/') { /* ** Time specified. */ ++strp; strp = getoffset(strp, &rulep->r_time); } else rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */ return strp; } /* ** Given the Epoch-relative time of January 1, 00:00:00 UTC, in a year, the ** year, a rule, and the offset from UT at the time that rule takes effect, ** calculate the Epoch-relative time that rule takes effect. */ static time_t transtime(const time_t janfirst, const int year, const struct rule *const rulep, const int_fast32_t offset) { int leapyear; time_t value; int i; int d, m1, yy0, yy1, yy2, dow; INITIALIZE(value); leapyear = isleap(year); switch (rulep->r_type) { case JULIAN_DAY: /* ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap ** years. ** In non-leap years, or if the day number is 59 or less, just ** add SECSPERDAY times the day number-1 to the time of ** January 1, midnight, to get the day. */ value = (time_t)(janfirst + (rulep->r_day - 1) * SECSPERDAY); if (leapyear && rulep->r_day >= 60) value += SECSPERDAY; break; case DAY_OF_YEAR: /* ** n - day of year. ** Just add SECSPERDAY times the day number to the time of ** January 1, midnight, to get the day. */ value = (time_t)(janfirst + rulep->r_day * SECSPERDAY); break; case MONTH_NTH_DAY_OF_WEEK: /* ** Mm.n.d - nth "dth day" of month m. */ value = janfirst; for (i = 0; i < rulep->r_mon - 1; ++i) value += (time_t)(mon_lengths[leapyear][i] * SECSPERDAY); /* ** Use Zeller's Congruence to get day-of-week of first day of ** month. */ m1 = (rulep->r_mon + 9) % 12 + 1; yy0 = (rulep->r_mon <= 2) ? (year - 1) : year; yy1 = yy0 / 100; yy2 = yy0 % 100; dow = ((26 * m1 - 2) / 10 + 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7; if (dow < 0) dow += DAYSPERWEEK; /* ** "dow" is the day-of-week of the first day of the month. Get ** the day-of-month (zero-origin) of the first "dow" day of the ** month. */ d = rulep->r_day - dow; if (d < 0) d += DAYSPERWEEK; for (i = 1; i < rulep->r_week; ++i) { if (d + DAYSPERWEEK >= mon_lengths[leapyear][rulep->r_mon - 1]) break; d += DAYSPERWEEK; } /* ** "d" is the day-of-month (zero-origin) of the day we want. */ value += (time_t)(d * SECSPERDAY); break; } /* ** "value" is the Epoch-relative time of 00:00:00 UT on the day in ** question. To get the Epoch-relative time of the specified local ** time on that day, add the transition time and the current offset ** from UT. */ return (time_t)(value + rulep->r_time + offset); } /* ** Given a POSIX section 8-style TZ string, fill in the rule tables as ** appropriate. */ static int tzparse(timezone_t sp, const char *name, const int lastditch) { const char * stdname; const char * dstname; size_t stdlen; size_t dstlen; int_fast32_t stdoffset; int_fast32_t dstoffset; time_t * atp; unsigned char * typep; char * cp; int load_result; INITIALIZE(dstname); stdname = name; if (lastditch) { stdlen = strlen(name); /* length of standard zone name */ name += stdlen; if (stdlen >= sizeof sp->chars) stdlen = (sizeof sp->chars) - 1; stdoffset = 0; } else { if (*name == '<') { name++; stdname = name; name = getqzname(name, '>'); if (*name != '>') return (-1); stdlen = name - stdname; name++; } else { name = getzname(name); stdlen = name - stdname; } if (*name == '\0') return -1; name = getoffset(name, &stdoffset); if (name == NULL) return -1; } load_result = tzload(sp, TZDEFRULES, FALSE); if (load_result != 0) sp->leapcnt = 0; /* so, we're off a little */ if (*name != '\0') { if (*name == '<') { dstname = ++name; name = getqzname(name, '>'); if (*name != '>') return -1; dstlen = name - dstname; name++; } else { dstname = name; name = getzname(name); dstlen = name - dstname; /* length of DST zone name */ } if (*name != '\0' && *name != ',' && *name != ';') { name = getoffset(name, &dstoffset); if (name == NULL) return -1; } else dstoffset = stdoffset - SECSPERHOUR; if (*name == '\0' && load_result != 0) name = TZDEFRULESTRING; if (*name == ',' || *name == ';') { struct rule start; struct rule end; int year; int yearlim; time_t janfirst; time_t starttime; time_t endtime; ++name; if ((name = getrule(name, &start)) == NULL) return -1; if (*name++ != ',') return -1; if ((name = getrule(name, &end)) == NULL) return -1; if (*name != '\0') return -1; sp->typecnt = 2; /* standard time and DST */ /* ** Two transitions per year, from EPOCH_YEAR forward. */ memset(sp->ttis, 0, sizeof(sp->ttis)); sp->ttis[0].tt_gmtoff = -dstoffset; sp->ttis[0].tt_isdst = 1; sp->ttis[0].tt_abbrind = (int)(stdlen + 1); sp->ttis[1].tt_gmtoff = -stdoffset; sp->ttis[1].tt_isdst = 0; sp->ttis[1].tt_abbrind = 0; atp = sp->ats; typep = sp->types; janfirst = 0; sp->timecnt = 0; yearlim = EPOCH_YEAR + YEARSPERREPEAT; for (year = EPOCH_YEAR; year < yearlim; year++) { int_fast32_t yearsecs; starttime = transtime(janfirst, year, &start, stdoffset); endtime = transtime(janfirst, year, &end, dstoffset); yearsecs = (year_lengths[isleap(year)] * SECSPERDAY); if (starttime > endtime || (starttime < endtime && (endtime - starttime < (yearsecs + (stdoffset - dstoffset))))) { if (&sp->ats[TZ_MAX_TIMES - 2] < atp) break; yearlim = year + YEARSPERREPEAT + 1; if (starttime > endtime) { *atp++ = endtime; *typep++ = 1; /* DST ends */ *atp++ = starttime; *typep++ = 0; /* DST begins */ } else { *atp++ = starttime; *typep++ = 0; /* DST begins */ *atp++ = endtime; *typep++ = 1; /* DST ends */ } } if (time_t_max - janfirst < yearsecs) break; janfirst += yearsecs; } _DIAGASSERT(__type_fit(int, atp - sp->ats)); sp->timecnt = (int)(atp - sp->ats); if (!sp->timecnt) sp->typecnt = 1; /* Perpetual DST. */ } else { int_fast32_t theirstdoffset; int_fast32_t theirdstoffset; int_fast32_t theiroffset; int isdst; int i; int j; if (*name != '\0') return -1; /* ** Initial values of theirstdoffset and theirdstoffset. */ theirstdoffset = 0; for (i = 0; i < sp->timecnt; ++i) { j = sp->types[i]; if (!sp->ttis[j].tt_isdst) { theirstdoffset = -sp->ttis[j].tt_gmtoff; break; } } theirdstoffset = 0; for (i = 0; i < sp->timecnt; ++i) { j = sp->types[i]; if (sp->ttis[j].tt_isdst) { theirdstoffset = -sp->ttis[j].tt_gmtoff; break; } } /* ** Initially we're assumed to be in standard time. */ isdst = FALSE; theiroffset = theirstdoffset; /* ** Now juggle transition times and types ** tracking offsets as you do. */ for (i = 0; i < sp->timecnt; ++i) { j = sp->types[i]; sp->types[i] = sp->ttis[j].tt_isdst; if (sp->ttis[j].tt_ttisgmt) { /* No adjustment to transition time */ } else { /* ** If summer time is in effect, and the ** transition time was not specified as ** standard time, add the summer time ** offset to the transition time; ** otherwise, add the standard time ** offset to the transition time. */ /* ** Transitions from DST to DDST ** will effectively disappear since ** POSIX provides for only one DST ** offset. */ if (isdst && !sp->ttis[j].tt_ttisstd) { sp->ats[i] += (time_t) (dstoffset - theirdstoffset); } else { sp->ats[i] += (time_t) (stdoffset - theirstdoffset); } } theiroffset = -sp->ttis[j].tt_gmtoff; if (!sp->ttis[j].tt_isdst) theirstdoffset = theiroffset; else theirdstoffset = theiroffset; } /* ** Finally, fill in ttis. ** ttisstd and ttisgmt need not be handled */ memset(sp->ttis, 0, sizeof(sp->ttis)); sp->ttis[0].tt_gmtoff = -stdoffset; sp->ttis[0].tt_isdst = FALSE; sp->ttis[0].tt_abbrind = 0; sp->ttis[1].tt_gmtoff = -dstoffset; sp->ttis[1].tt_isdst = TRUE; sp->ttis[1].tt_abbrind = (int)(stdlen + 1); sp->typecnt = 2; } } else { dstlen = 0; sp->typecnt = 1; /* only standard time */ sp->timecnt = 0; memset(sp->ttis, 0, sizeof(sp->ttis)); sp->ttis[0].tt_gmtoff = -stdoffset; sp->ttis[0].tt_isdst = 0; sp->ttis[0].tt_abbrind = 0; } sp->charcnt = (int)(stdlen + 1); if (dstlen != 0) sp->charcnt += (int)(dstlen + 1); if ((size_t) sp->charcnt > sizeof sp->chars) return -1; cp = sp->chars; (void) strncpy(cp, stdname, stdlen); cp += stdlen; *cp++ = '\0'; if (dstlen != 0) { (void) strncpy(cp, dstname, dstlen); *(cp + dstlen) = '\0'; } return 0; } static void gmtload(timezone_t sp) { if (tzload(sp, gmt, TRUE) != 0) (void) tzparse(sp, gmt, TRUE); } timezone_t tzalloc(const char *name) { timezone_t sp = calloc(1, sizeof *sp); if (sp == NULL) return NULL; if (tzload(sp, name, TRUE) != 0) { free(sp); return NULL; } settzname_z(sp); return sp; } void tzfree(const timezone_t sp) { free(sp); } static void tzsetwall_unlocked(void) { if (lcl_is_set < 0) return; lcl_is_set = -1; if (lclptr == NULL) { int saveerrno = errno; lclptr = calloc(1, sizeof *lclptr); errno = saveerrno; if (lclptr == NULL) { settzname(); /* all we can do */ return; } } if (tzload(lclptr, NULL, TRUE) != 0) gmtload(lclptr); settzname(); } #ifndef STD_INSPIRED /* ** A non-static declaration of tzsetwall in a system header file ** may cause a warning about this upcoming static declaration... */ static #endif /* !defined STD_INSPIRED */ void tzsetwall(void) { rwlock_wrlock(&lcl_lock); tzsetwall_unlocked(); rwlock_unlock(&lcl_lock); } #ifndef STD_INSPIRED /* ** A non-static declaration of tzsetwall in a system header file ** may cause a warning about this upcoming static declaration... */ static #endif /* !defined STD_INSPIRED */ void tzset_unlocked(void) { const char * name; name = getenv("TZ"); if (name == NULL) { tzsetwall_unlocked(); return; } if (lcl_is_set > 0 && strcmp(lcl_TZname, name) == 0) return; lcl_is_set = strlen(name) < sizeof lcl_TZname; if (lcl_is_set) (void)strlcpy(lcl_TZname, name, sizeof(lcl_TZname)); if (lclptr == NULL) { int saveerrno = errno; lclptr = calloc(1, sizeof *lclptr); errno = saveerrno; if (lclptr == NULL) { settzname(); /* all we can do */ return; } } if (*name == '\0') { /* ** User wants it fast rather than right. */ lclptr->leapcnt = 0; /* so, we're off a little */ lclptr->timecnt = 0; lclptr->typecnt = 0; lclptr->ttis[0].tt_isdst = 0; lclptr->ttis[0].tt_gmtoff = 0; lclptr->ttis[0].tt_abbrind = 0; (void) strlcpy(lclptr->chars, gmt, sizeof(lclptr->chars)); } else if (tzload(lclptr, name, TRUE) != 0) if (name[0] == ':' || tzparse(lclptr, name, FALSE) != 0) (void) gmtload(lclptr); settzname(); } void tzset(void) { rwlock_wrlock(&lcl_lock); tzset_unlocked(); rwlock_unlock(&lcl_lock); } /* ** The easy way to behave "as if no library function calls" localtime ** is to not call it--so we drop its guts into "localsub", which can be ** freely called. (And no, the PANS doesn't require the above behavior-- ** but it *is* desirable.) ** ** The unused offset argument is for the benefit of mktime variants. */ /*ARGSUSED*/ static struct tm * localsub(const timezone_t sp, const time_t * const timep, const int_fast32_t offset, struct tm *const tmp) { const struct ttinfo * ttisp; int i; struct tm * result; const time_t t = *timep; if ((sp->goback && t < sp->ats[0]) || (sp->goahead && t > sp->ats[sp->timecnt - 1])) { time_t newt = t; time_t seconds; time_t years; if (t < sp->ats[0]) seconds = sp->ats[0] - t; else seconds = t - sp->ats[sp->timecnt - 1]; --seconds; years = (time_t)((seconds / SECSPERREPEAT + 1) * YEARSPERREPEAT); seconds = (time_t)(years * AVGSECSPERYEAR); if (t < sp->ats[0]) newt += seconds; else newt -= seconds; if (newt < sp->ats[0] || newt > sp->ats[sp->timecnt - 1]) return NULL; /* "cannot happen" */ result = localsub(sp, &newt, offset, tmp); if (result == tmp) { time_t newy; newy = tmp->tm_year; if (t < sp->ats[0]) newy -= years; else newy += years; tmp->tm_year = (int)newy; if (tmp->tm_year != newy) return NULL; } return result; } if (sp->timecnt == 0 || t < sp->ats[0]) { i = sp->defaulttype; } else { int lo = 1; int hi = sp->timecnt; while (lo < hi) { int mid = (lo + hi) / 2; if (t < sp->ats[mid]) hi = mid; else lo = mid + 1; } i = (int) sp->types[lo - 1]; } ttisp = &sp->ttis[i]; /* ** To get (wrong) behavior that's compatible with System V Release 2.0 ** you'd replace the statement below with ** t += ttisp->tt_gmtoff; ** timesub(&t, 0L, sp, tmp); */ result = timesub(sp, &t, ttisp->tt_gmtoff, tmp); tmp->tm_isdst = ttisp->tt_isdst; if (sp == lclptr) tzname[tmp->tm_isdst] = &sp->chars[ttisp->tt_abbrind]; #ifdef TM_ZONE tmp->TM_ZONE = &sp->chars[ttisp->tt_abbrind]; #endif /* defined TM_ZONE */ return result; } /* ** Re-entrant version of localtime. */ struct tm * localtime_r(const time_t * __restrict timep, struct tm *tmp) { rwlock_rdlock(&lcl_lock); tzset_unlocked(); tmp = localtime_rz(lclptr, timep, tmp); rwlock_unlock(&lcl_lock); return tmp; } struct tm * localtime(const time_t *const timep) { return localtime_r(timep, &tm); } struct tm * localtime_rz(const timezone_t sp, const time_t * __restrict timep, struct tm *tmp) { if (sp == NULL) tmp = gmtsub(NULL, timep, 0, tmp); else tmp = localsub(sp, timep, 0, tmp); if (tmp == NULL) errno = EOVERFLOW; return tmp; } /* ** gmtsub is to gmtime as localsub is to localtime. */ static struct tm * gmtsub(const timezone_t sp, const time_t *const timep, const int_fast32_t offset, struct tm *const tmp) { struct tm * result; #ifdef _REENTRANT static mutex_t gmt_mutex = MUTEX_INITIALIZER; #endif mutex_lock(&gmt_mutex); if (!gmt_is_set) { int saveerrno; gmt_is_set = TRUE; saveerrno = errno; gmtptr = calloc(1, sizeof *gmtptr); errno = saveerrno; if (gmtptr != NULL) gmtload(gmtptr); } mutex_unlock(&gmt_mutex); result = timesub(gmtptr, timep, offset, tmp); #ifdef TM_ZONE /* ** Could get fancy here and deliver something such as ** "UT+xxxx" or "UT-xxxx" if offset is non-zero, ** but this is no time for a treasure hunt. */ if (offset != 0) tmp->TM_ZONE = (__aconst char *)__UNCONST(wildabbr); else { if (gmtptr == NULL) tmp->TM_ZONE = (__aconst char *)__UNCONST(gmt); else tmp->TM_ZONE = gmtptr->chars; } #endif /* defined TM_ZONE */ return result; } struct tm * gmtime(const time_t *const timep) { struct tm *tmp = gmtsub(NULL, timep, 0, &tm); if (tmp == NULL) errno = EOVERFLOW; return tmp; } /* ** Re-entrant version of gmtime. */ struct tm * gmtime_r(const time_t * const timep, struct tm *tmp) { tmp = gmtsub(NULL, timep, 0, tmp); if (tmp == NULL) errno = EOVERFLOW; return tmp; } #ifdef STD_INSPIRED struct tm * offtime(const time_t *const timep, long offset) { struct tm *tmp; if ((offset > 0 && offset > INT_FAST32_MAX) || (offset < 0 && offset < INT_FAST32_MIN)) { errno = EOVERFLOW; return NULL; } tmp = gmtsub(NULL, timep, (int_fast32_t)offset, &tm); if (tmp == NULL) errno = EOVERFLOW; return tmp; } struct tm * offtime_r(const time_t *timep, long offset, struct tm *tmp) { if ((offset > 0 && offset > INT_FAST32_MAX) || (offset < 0 && offset < INT_FAST32_MIN)) { errno = EOVERFLOW; return NULL; } tmp = gmtsub(NULL, timep, (int_fast32_t)offset, tmp); if (tmp == NULL) errno = EOVERFLOW; return tmp; } #endif /* defined STD_INSPIRED */ /* ** Return the number of leap years through the end of the given year ** where, to make the math easy, the answer for year zero is defined as zero. */ static int leaps_thru_end_of(const int y) { return (y >= 0) ? (y / 4 - y / 100 + y / 400) : -(leaps_thru_end_of(-(y + 1)) + 1); } static struct tm * timesub(const timezone_t sp, const time_t *const timep, const int_fast32_t offset, struct tm *const tmp) { const struct lsinfo * lp; time_t tdays; int idays; /* unsigned would be so 2003 */ int_fast64_t rem; int y; const int * ip; int_fast64_t corr; int hit; int i; corr = 0; hit = 0; i = (sp == NULL) ? 0 : sp->leapcnt; while (--i >= 0) { lp = &sp->lsis[i]; if (*timep >= lp->ls_trans) { if (*timep == lp->ls_trans) { hit = ((i == 0 && lp->ls_corr > 0) || lp->ls_corr > sp->lsis[i - 1].ls_corr); if (hit) while (i > 0 && sp->lsis[i].ls_trans == sp->lsis[i - 1].ls_trans + 1 && sp->lsis[i].ls_corr == sp->lsis[i - 1].ls_corr + 1) { ++hit; --i; } } corr = lp->ls_corr; break; } } y = EPOCH_YEAR; tdays = (time_t)(*timep / SECSPERDAY); rem = (int_fast64_t) (*timep - tdays * SECSPERDAY); while (tdays < 0 || tdays >= year_lengths[isleap(y)]) { int newy; time_t tdelta; int idelta; int leapdays; tdelta = tdays / DAYSPERLYEAR; if (! ((! TYPE_SIGNED(time_t) || INT_MIN <= tdelta) && tdelta <= INT_MAX)) return NULL; idelta = tdelta; if (idelta == 0) idelta = (tdays < 0) ? -1 : 1; newy = y; if (increment_overflow(&newy, idelta)) return NULL; leapdays = leaps_thru_end_of(newy - 1) - leaps_thru_end_of(y - 1); tdays -= ((time_t) newy - y) * DAYSPERNYEAR; tdays -= leapdays; y = newy; } { int_fast32_t seconds; seconds = (int_fast32_t)(tdays * SECSPERDAY); tdays = (time_t)(seconds / SECSPERDAY); rem += (int_fast64_t)(seconds - tdays * SECSPERDAY); } /* ** Given the range, we can now fearlessly cast... */ idays = (int) tdays; rem += offset - corr; while (rem < 0) { rem += SECSPERDAY; --idays; } while (rem >= SECSPERDAY) { rem -= SECSPERDAY; ++idays; } while (idays < 0) { if (increment_overflow(&y, -1)) return NULL; idays += year_lengths[isleap(y)]; } while (idays >= year_lengths[isleap(y)]) { idays -= year_lengths[isleap(y)]; if (increment_overflow(&y, 1)) return NULL; } tmp->tm_year = y; if (increment_overflow(&tmp->tm_year, -TM_YEAR_BASE)) return NULL; tmp->tm_yday = idays; /* ** The "extra" mods below avoid overflow problems. */ tmp->tm_wday = EPOCH_WDAY + ((y - EPOCH_YEAR) % DAYSPERWEEK) * (DAYSPERNYEAR % DAYSPERWEEK) + leaps_thru_end_of(y - 1) - leaps_thru_end_of(EPOCH_YEAR - 1) + idays; tmp->tm_wday %= DAYSPERWEEK; if (tmp->tm_wday < 0) tmp->tm_wday += DAYSPERWEEK; tmp->tm_hour = (int) (rem / SECSPERHOUR); rem %= SECSPERHOUR; tmp->tm_min = (int) (rem / SECSPERMIN); /* ** A positive leap second requires a special ** representation. This uses "... ??:59:60" et seq. */ tmp->tm_sec = (int) (rem % SECSPERMIN) + hit; ip = mon_lengths[isleap(y)]; for (tmp->tm_mon = 0; idays >= ip[tmp->tm_mon]; ++(tmp->tm_mon)) idays -= ip[tmp->tm_mon]; tmp->tm_mday = (int) (idays + 1); tmp->tm_isdst = 0; #ifdef TM_GMTOFF tmp->TM_GMTOFF = offset; #endif /* defined TM_GMTOFF */ return tmp; } #if !defined(__minix) || !defined(_LIBMINC) char * ctime(const time_t *const timep) { /* ** Section 4.12.3.2 of X3.159-1989 requires that ** The ctime function converts the calendar time pointed to by timer ** to local time in the form of a string. It is equivalent to ** asctime(localtime(timer)) */ struct tm *rtm = localtime(timep); if (rtm == NULL) return NULL; return asctime(rtm); } char * ctime_r(const time_t *const timep, char *buf) { struct tm mytm, *rtm; rtm = localtime_r(timep, &mytm); if (rtm == NULL) return NULL; return asctime_r(rtm, buf); } char * ctime_rz(const timezone_t sp, const time_t * timep, char *buf) { struct tm mytm, *rtm; rtm = localtime_rz(sp, timep, &mytm); if (rtm == NULL) return NULL; return asctime_r(rtm, buf); } #endif /* !defined(__minix) || !defined(_LIBMINC) */ /* ** Adapted from code provided by Robert Elz, who writes: ** The "best" way to do mktime I think is based on an idea of Bob ** Kridle's (so its said...) from a long time ago. ** It does a binary search of the time_t space. Since time_t's are ** just 32 bits, its a max of 32 iterations (even at 64 bits it ** would still be very reasonable). */ #ifndef WRONG #define WRONG ((time_t)-1) #endif /* !defined WRONG */ /* ** Simplified normalize logic courtesy Paul Eggert. */ static int increment_overflow(int *const ip, int j) { int i = *ip; /* ** If i >= 0 there can only be overflow if i + j > INT_MAX ** or if j > INT_MAX - i; given i >= 0, INT_MAX - i cannot overflow. ** If i < 0 there can only be overflow if i + j < INT_MIN ** or if j < INT_MIN - i; given i < 0, INT_MIN - i cannot overflow. */ if ((i >= 0) ? (j > INT_MAX - i) : (j < INT_MIN - i)) return TRUE; *ip += j; return FALSE; } static int increment_overflow32(int_fast32_t *const lp, int const m) { int_fast32_t l = *lp; if ((l >= 0) ? (m > INT_FAST32_MAX - l) : (m < INT_FAST32_MIN - l)) return TRUE; *lp += m; return FALSE; } static int normalize_overflow(int *const tensptr, int *const unitsptr, const int base) { int tensdelta; tensdelta = (*unitsptr >= 0) ? (*unitsptr / base) : (-1 - (-1 - *unitsptr) / base); *unitsptr -= tensdelta * base; return increment_overflow(tensptr, tensdelta); } static int normalize_overflow32(int_fast32_t *const tensptr, int *const unitsptr, const int base) { int tensdelta; tensdelta = (*unitsptr >= 0) ? (*unitsptr / base) : (-1 - (-1 - *unitsptr) / base); *unitsptr -= tensdelta * base; return increment_overflow32(tensptr, tensdelta); } static int tmcomp(const struct tm *const atmp, const struct tm *const btmp) { int result; if (atmp->tm_year != btmp->tm_year) return atmp->tm_year < btmp->tm_year ? -1 : 1; if ((result = (atmp->tm_mon - btmp->tm_mon)) == 0 && (result = (atmp->tm_mday - btmp->tm_mday)) == 0 && (result = (atmp->tm_hour - btmp->tm_hour)) == 0 && (result = (atmp->tm_min - btmp->tm_min)) == 0) result = atmp->tm_sec - btmp->tm_sec; return result; } static time_t time2sub(const timezone_t sp, struct tm *const tmp, subfun_t funcp, const int_fast32_t offset, int *const okayp, const int do_norm_secs) { int dir; int i, j; int saved_seconds; int_fast32_t li; time_t lo; time_t hi; #ifdef NO_ERROR_IN_DST_GAP time_t ilo; #endif int_fast32_t y; time_t newt; time_t t; struct tm yourtm, mytm; *okayp = FALSE; yourtm = *tmp; #ifdef NO_ERROR_IN_DST_GAP again: #endif if (do_norm_secs) { if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec, SECSPERMIN)) goto overflow; } if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR)) goto overflow; if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY)) goto overflow; y = yourtm.tm_year; if (normalize_overflow32(&y, &yourtm.tm_mon, MONSPERYEAR)) goto overflow; /* ** Turn y into an actual year number for now. ** It is converted back to an offset from TM_YEAR_BASE later. */ if (increment_overflow32(&y, TM_YEAR_BASE)) goto overflow; while (yourtm.tm_mday <= 0) { if (increment_overflow32(&y, -1)) goto overflow; li = y + (1 < yourtm.tm_mon); yourtm.tm_mday += year_lengths[isleap(li)]; } while (yourtm.tm_mday > DAYSPERLYEAR) { li = y + (1 < yourtm.tm_mon); yourtm.tm_mday -= year_lengths[isleap(li)]; if (increment_overflow32(&y, 1)) goto overflow; } for ( ; ; ) { i = mon_lengths[isleap(y)][yourtm.tm_mon]; if (yourtm.tm_mday <= i) break; yourtm.tm_mday -= i; if (++yourtm.tm_mon >= MONSPERYEAR) { yourtm.tm_mon = 0; if (increment_overflow32(&y, 1)) goto overflow; } } if (increment_overflow32(&y, -TM_YEAR_BASE)) goto overflow; yourtm.tm_year = (int)y; if (yourtm.tm_year != y) goto overflow; if (yourtm.tm_sec >= 0 && yourtm.tm_sec < SECSPERMIN) saved_seconds = 0; else if (y + TM_YEAR_BASE < EPOCH_YEAR) { /* ** We can't set tm_sec to 0, because that might push the ** time below the minimum representable time. ** Set tm_sec to 59 instead. ** This assumes that the minimum representable time is ** not in the same minute that a leap second was deleted from, ** which is a safer assumption than using 58 would be. */ if (increment_overflow(&yourtm.tm_sec, 1 - SECSPERMIN)) goto overflow; saved_seconds = yourtm.tm_sec; yourtm.tm_sec = SECSPERMIN - 1; } else { saved_seconds = yourtm.tm_sec; yourtm.tm_sec = 0; } /* ** Do a binary search (this works whatever time_t's type is). */ /* LINTED const not */ if (!TYPE_SIGNED(time_t)) { lo = 0; hi = lo - 1; } else { lo = 1; for (i = 0; i < (int) TYPE_BIT(time_t) - 1; ++i) lo *= 2; hi = -(lo + 1); } #ifdef NO_ERROR_IN_DST_GAP ilo = lo; #endif for ( ; ; ) { t = lo / 2 + hi / 2; if (t < lo) t = lo; else if (t > hi) t = hi; if ((*funcp)(sp, &t, offset, &mytm) == NULL) { /* ** Assume that t is too extreme to be represented in ** a struct tm; arrange things so that it is less ** extreme on the next pass. */ dir = (t > 0) ? 1 : -1; } else dir = tmcomp(&mytm, &yourtm); if (dir != 0) { if (t == lo) { if (t == time_t_max) goto overflow; ++t; ++lo; } else if (t == hi) { if (t == time_t_min) goto overflow; --t; --hi; } #ifdef NO_ERROR_IN_DST_GAP if (ilo != lo && lo - 1 == hi && yourtm.tm_isdst < 0 && do_norm_secs) { for (i = sp->typecnt - 1; i >= 0; --i) { for (j = sp->typecnt - 1; j >= 0; --j) { time_t off; if (sp->ttis[j].tt_isdst == sp->ttis[i].tt_isdst) continue; off = sp->ttis[j].tt_gmtoff - sp->ttis[i].tt_gmtoff; yourtm.tm_sec += off < 0 ? -off : off; goto again; } } } #endif if (lo > hi) goto invalid; if (dir > 0) hi = t; else lo = t; continue; } if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst) break; /* ** Right time, wrong type. ** Hunt for right time, right type. ** It's okay to guess wrong since the guess ** gets checked. */ if (sp == NULL) goto invalid; for (i = sp->typecnt - 1; i >= 0; --i) { if (sp->ttis[i].tt_isdst != yourtm.tm_isdst) continue; for (j = sp->typecnt - 1; j >= 0; --j) { if (sp->ttis[j].tt_isdst == yourtm.tm_isdst) continue; newt = (time_t)(t + sp->ttis[j].tt_gmtoff - sp->ttis[i].tt_gmtoff); if ((*funcp)(sp, &newt, offset, &mytm) == NULL) continue; if (tmcomp(&mytm, &yourtm) != 0) continue; if (mytm.tm_isdst != yourtm.tm_isdst) continue; /* ** We have a match. */ t = newt; goto label; } } goto invalid; } label: newt = t + saved_seconds; if ((newt < t) != (saved_seconds < 0)) goto overflow; t = newt; if ((*funcp)(sp, &t, offset, tmp)) { *okayp = TRUE; return t; } overflow: errno = EOVERFLOW; return WRONG; invalid: errno = EINVAL; return WRONG; } static time_t time2(const timezone_t sp, struct tm *const tmp, subfun_t funcp, const int_fast32_t offset, int *const okayp) { time_t t; /* ** First try without normalization of seconds ** (in case tm_sec contains a value associated with a leap second). ** If that fails, try with normalization of seconds. */ t = time2sub(sp, tmp, funcp, offset, okayp, FALSE); return *okayp ? t : time2sub(sp, tmp, funcp, offset, okayp, TRUE); } static time_t time1(const timezone_t sp, struct tm *const tmp, subfun_t funcp, const int_fast32_t offset) { time_t t; int samei, otheri; int sameind, otherind; int i; int nseen; int seen[TZ_MAX_TYPES]; int types[TZ_MAX_TYPES]; int okay; if (tmp == NULL) { errno = EINVAL; return WRONG; } if (tmp->tm_isdst > 1) tmp->tm_isdst = 1; t = time2(sp, tmp, funcp, offset, &okay); #ifdef PCTS /* ** PCTS code courtesy Grant Sullivan. */ if (okay) return t; if (tmp->tm_isdst < 0) tmp->tm_isdst = 0; /* reset to std and try again */ #endif /* defined PCTS */ #ifndef PCTS if (okay || tmp->tm_isdst < 0) return t; #endif /* !defined PCTS */ /* ** We're supposed to assume that somebody took a time of one type ** and did some math on it that yielded a "struct tm" that's bad. ** We try to divine the type they started from and adjust to the ** type they need. */ if (sp == NULL) { errno = EINVAL; return WRONG; } for (i = 0; i < sp->typecnt; ++i) seen[i] = FALSE; nseen = 0; for (i = sp->timecnt - 1; i >= 0; --i) if (!seen[sp->types[i]]) { seen[sp->types[i]] = TRUE; types[nseen++] = sp->types[i]; } for (sameind = 0; sameind < nseen; ++sameind) { samei = types[sameind]; if (sp->ttis[samei].tt_isdst != tmp->tm_isdst) continue; for (otherind = 0; otherind < nseen; ++otherind) { otheri = types[otherind]; if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst) continue; tmp->tm_sec += (int)(sp->ttis[otheri].tt_gmtoff - sp->ttis[samei].tt_gmtoff); tmp->tm_isdst = !tmp->tm_isdst; t = time2(sp, tmp, funcp, offset, &okay); if (okay) return t; tmp->tm_sec -= (int)(sp->ttis[otheri].tt_gmtoff - sp->ttis[samei].tt_gmtoff); tmp->tm_isdst = !tmp->tm_isdst; } } errno = EOVERFLOW; return WRONG; } time_t mktime_z(const timezone_t sp, struct tm *const tmp) { time_t t; if (sp == NULL) t = time1(NULL, tmp, gmtsub, 0); else t = time1(sp, tmp, localsub, 0); return t; } time_t mktime(struct tm *const tmp) { time_t result; rwlock_wrlock(&lcl_lock); tzset_unlocked(); result = mktime_z(lclptr, tmp); rwlock_unlock(&lcl_lock); return result; } #ifdef STD_INSPIRED time_t timelocal_z(const timezone_t sp, struct tm *const tmp) { if (tmp != NULL) tmp->tm_isdst = -1; /* in case it wasn't initialized */ return mktime_z(sp, tmp); } time_t timelocal(struct tm *const tmp) { if (tmp != NULL) tmp->tm_isdst = -1; /* in case it wasn't initialized */ return mktime(tmp); } time_t timegm(struct tm *const tmp) { time_t t; if (tmp != NULL) tmp->tm_isdst = 0; t = time1(gmtptr, tmp, gmtsub, 0); return t; } time_t timeoff(struct tm *const tmp, long offset) { time_t t; if ((offset > 0 && offset > INT_FAST32_MAX) || (offset < 0 && offset < INT_FAST32_MIN)) { errno = EOVERFLOW; return -1; } if (tmp != NULL) tmp->tm_isdst = 0; t = time1(gmtptr, tmp, gmtsub, (int_fast32_t)offset); return t; } #endif /* defined STD_INSPIRED */ #ifdef CMUCS /* ** The following is supplied for compatibility with ** previous versions of the CMUCS runtime library. */ long gtime(struct tm *const tmp) { const time_t t = mktime(tmp); if (t == WRONG) return -1; return t; } #endif /* defined CMUCS */ /* ** XXX--is the below the right way to conditionalize?? */ #ifdef STD_INSPIRED /* ** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 ** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which ** is not the case if we are accounting for leap seconds. ** So, we provide the following conversion routines for use ** when exchanging timestamps with POSIX conforming systems. */ static int_fast64_t leapcorr(const timezone_t sp, time_t *timep) { struct lsinfo * lp; int i; i = sp->leapcnt; while (--i >= 0) { lp = &sp->lsis[i]; if (*timep >= lp->ls_trans) return lp->ls_corr; } return 0; } time_t time2posix_z(const timezone_t sp, time_t t) { return (time_t)(t - leapcorr(sp, &t)); } time_t time2posix(time_t t) { time_t result; rwlock_wrlock(&lcl_lock); tzset_unlocked(); result = (time_t)(t - leapcorr(lclptr, &t)); rwlock_unlock(&lcl_lock); return (result); } time_t posix2time_z(const timezone_t sp, time_t t) { time_t x; time_t y; /* ** For a positive leap second hit, the result ** is not unique. For a negative leap second ** hit, the corresponding time doesn't exist, ** so we return an adjacent second. */ x = (time_t)(t + leapcorr(sp, &t)); y = (time_t)(x - leapcorr(sp, &x)); if (y < t) { do { x++; y = (time_t)(x - leapcorr(sp, &x)); } while (y < t); if (t != y) { return x - 1; } } else if (y > t) { do { --x; y = (time_t)(x - leapcorr(sp, &x)); } while (y > t); if (t != y) { return x + 1; } } return x; } time_t posix2time(time_t t) { time_t result; rwlock_wrlock(&lcl_lock); tzset_unlocked(); result = posix2time_z(lclptr, t); rwlock_unlock(&lcl_lock); return result; } #endif /* defined STD_INSPIRED */