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e1f8c66d0b
bionic/libc/tzcode/localtime.c
Elliott Hughes 76dfa6e351 Remove mktime_tz. 
Bug: http://b/15765976
Change-Id: Ifc8cd19ae621e611d66173ae927ef9a0445965c1
2016-01-06 09:15:02 -08:00

2466 lines
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/*
** This file is in the public domain, so clarified as of
** 1996-06-05 by Arthur David Olson.
*/
/*
** Leap second handling from Bradley White.
** POSIX-style TZ environment variable handling from Guy Harris.
*/
/*LINTLIBRARY*/
#define LOCALTIME_IMPLEMENTATION
#include "private.h"
#include "tzfile.h"
#include "fcntl.h"
#if THREAD_SAFE
# include <pthread.h>
static pthread_mutex_t locallock = PTHREAD_MUTEX_INITIALIZER;
static int lock(void) { return pthread_mutex_lock(&locallock); }
static void unlock(void) { pthread_mutex_unlock(&locallock); }
#else
static int lock(void) { return 0; }
static void unlock(void) { }
#endif
/* NETBSD_INSPIRED_EXTERN functions are exported to callers if
NETBSD_INSPIRED is defined, and are private otherwise. */
#if NETBSD_INSPIRED
# define NETBSD_INSPIRED_EXTERN
#else
# define NETBSD_INSPIRED_EXTERN static
#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 */
bool tt_isdst; /* used to set tm_isdst */
int tt_abbrind; /* abbreviation list index */
bool tt_ttisstd; /* transition is std time */
bool tt_ttisgmt; /* transition is UT */
};
struct lsinfo { /* leap second information */
time_t ls_trans; /* transition time */
int_fast64_t ls_corr; /* correction to apply */
};
#define SMALLEST(a, b) (((a) < (b)) ? (a) : (b))
#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;
bool goback;
bool goahead;
time_t ats[TZ_MAX_TIMES];
unsigned char types[TZ_MAX_TIMES];
struct ttinfo ttis[TZ_MAX_TYPES];
char chars[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 */
};
enum r_type {
JULIAN_DAY, /* Jn = Julian day */
DAY_OF_YEAR, /* n = day of year */
MONTH_NTH_DAY_OF_WEEK /* Mm.n.d = month, week, day of week */
};
struct rule {
enum r_type r_type; /* type of rule */
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 */
};
static struct tm *gmtsub(struct state const *, time_t const *, int_fast32_t,
struct tm *);
static bool increment_overflow(int *, int);
static bool increment_overflow_time(time_t *, int_fast32_t);
static bool normalize_overflow32(int_fast32_t *, int *, int);
static struct tm *timesub(time_t const *, int_fast32_t, struct state const *,
struct tm *);
static bool typesequiv(struct state const *, int, int);
static bool tzparse(char const *, struct state *, bool);
#ifdef ALL_STATE
static struct state * lclptr;
static struct state * gmtptr;
#endif /* defined ALL_STATE */
#ifndef ALL_STATE
static struct state lclmem;
static struct state gmtmem;
#define lclptr (&lclmem)
#define gmtptr (&gmtmem)
#endif /* State Farm */
#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;
char * tzname[2] = {
(char *) wildabbr,
(char *) wildabbr
};
/*
** 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
long timezone;
int daylight;
#endif /* defined USG_COMPAT */
#ifdef ALTZONE
long altzone;
#endif /* defined ALTZONE */
/* Initialize *S to a value based on GMTOFF, ISDST, and ABBRIND. */
static void
init_ttinfo(struct ttinfo *s, int_fast32_t gmtoff, bool isdst, int abbrind)
{
s->tt_gmtoff = gmtoff;
s->tt_isdst = isdst;
s->tt_abbrind = abbrind;
s->tt_ttisstd = false;
s->tt_ttisgmt = false;
}
static int_fast32_t
detzcode(const char *const codep)
{
register int_fast32_t result;
register int i;
int_fast32_t one = 1;
int_fast32_t halfmaxval = one << (32 - 2);
int_fast32_t maxval = halfmaxval - 1 + halfmaxval;
int_fast32_t minval = -1 - maxval;
result = codep[0] & 0x7f;
for (i = 1; i < 4; ++i)
result = (result << 8) | (codep[i] & 0xff);
if (codep[0] & 0x80) {
/* Do two's-complement negation even on non-two's-complement machines.
If the result would be minval - 1, return minval. */
result -= !TWOS_COMPLEMENT(int_fast32_t) && result != 0;
result += minval;
}
return result;
}
static int_fast64_t
detzcode64(const char *const codep)
{
register uint_fast64_t result;
register int i;
int_fast64_t one = 1;
int_fast64_t halfmaxval = one << (64 - 2);
int_fast64_t maxval = halfmaxval - 1 + halfmaxval;
int_fast64_t minval = -TWOS_COMPLEMENT(int_fast64_t) - maxval;
result = codep[0] & 0x7f;
for (i = 1; i < 8; ++i)
result = (result << 8) | (codep[i] & 0xff);
if (codep[0] & 0x80) {
/* Do two's-complement negation even on non-two's-complement machines.
If the result would be minval - 1, return minval. */
result -= !TWOS_COMPLEMENT(int_fast64_t) && result != 0;
result += minval;
}
return result;
}
static void
update_tzname_etc(struct state const *sp, struct ttinfo const *ttisp)
{
tzname[ttisp->tt_isdst] = (char *) &sp->chars[ttisp->tt_abbrind];
#ifdef USG_COMPAT
if (!ttisp->tt_isdst)
timezone = - ttisp->tt_gmtoff;
#endif
#ifdef ALTZONE
if (ttisp->tt_isdst)
altzone = - ttisp->tt_gmtoff;
#endif
}
static void
settzname(void)
{
register struct state * const sp = lclptr;
register int i;
tzname[0] = tzname[1] = (char *) 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] = (char *) gmt;
return;
}
/*
** And to get the latest zone names into tzname. . .
*/
for (i = 0; i < sp->typecnt; ++i) {
register const struct ttinfo * const ttisp = &sp->ttis[i];
update_tzname_etc(sp, ttisp);
}
for (i = 0; i < sp->timecnt; ++i) {
register const struct ttinfo * const ttisp =
&sp->ttis[
sp->types[i]];
update_tzname_etc(sp, ttisp);
#ifdef USG_COMPAT
if (ttisp->tt_isdst)
daylight = 1;
#endif /* defined USG_COMPAT */
}
}
static void
scrub_abbrs(struct state *sp)
{
int i;
/*
** 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) {
register const struct ttinfo * const ttisp = &sp->ttis[i];
register 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 bool
differ_by_repeat(const time_t t1, const time_t t0)
{
if (TYPE_BIT(time_t) - TYPE_SIGNED(time_t) < SECSPERREPEAT_BITS)
return 0;
#if defined(__LP64__) // 32-bit Android/glibc has a signed 32-bit time_t; 64-bit doesn't.
return t1 - t0 == SECSPERREPEAT;
#endif
}
/* Input buffer for data read from a compiled tz file. */
union input_buffer {
/* The first part of the buffer, interpreted as a header. */
struct tzhead tzhead;
/* The entire buffer. */
char buf[2 * sizeof(struct tzhead) + 2 * sizeof (struct state)
+ 4 * TZ_MAX_TIMES];
};
/* Local storage needed for 'tzloadbody'. */
union local_storage {
/* The file name to be opened. */
char fullname[FILENAME_MAX + 1];
/* The results of analyzing the file's contents after it is opened. */
struct {
/* The input buffer. */
union input_buffer u;
/* A temporary state used for parsing a TZ string in the file. */
struct state st;
} u;
};
static int __bionic_open_tzdata(const char*);
/* Load tz data from the file named NAME into *SP. Read extended
format if DOEXTEND. Use *LSP for temporary storage. Return 0 on
success, an errno value on failure. */
static int
tzloadbody(char const *name, struct state *sp, bool doextend,
union local_storage *lsp)
{
register int i;
register int fid;
register int stored;
register ssize_t nread;
#if !defined(__ANDROID__)
register bool doaccess;
register char *fullname = lsp->fullname;
#endif
register union input_buffer *up = &lsp->u.u;
register int tzheadsize = sizeof (struct tzhead);
sp->goback = sp->goahead = false;
if (! name) {
name = TZDEFAULT;
if (! name)
return EINVAL;
}
#if defined(__ANDROID__)
fid = __bionic_open_tzdata(name);
#else
if (name[0] == ':')
++name;
doaccess = name[0] == '/';
if (!doaccess) {
char const *p = TZDIR;
if (! p)
return EINVAL;
if (sizeof lsp->fullname - 1 <= strlen(p) + strlen(name))
return ENAMETOOLONG;
strcpy(fullname, p);
strcat(fullname, "/");
strcat(fullname, name);
/* Set doaccess if '.' (as in "../") shows up in name. */
if (strchr(name, '.'))
doaccess = true;
name = fullname;
}
if (doaccess && access(name, R_OK) != 0)
return errno;
fid = open(name, OPEN_MODE);
#endif
if (fid < 0)
return errno;
nread = read(fid, up->buf, sizeof up->buf);
if (nread < tzheadsize) {
int err = nread < 0 ? errno : EINVAL;
close(fid);
return err;
}
if (close(fid) < 0)
return errno;
for (stored = 4; stored <= 8; stored *= 2) {
int_fast32_t ttisstdcnt = detzcode(up->tzhead.tzh_ttisstdcnt);
int_fast32_t ttisgmtcnt = detzcode(up->tzhead.tzh_ttisgmtcnt);
int_fast32_t leapcnt = detzcode(up->tzhead.tzh_leapcnt);
int_fast32_t timecnt = detzcode(up->tzhead.tzh_timecnt);
int_fast32_t typecnt = detzcode(up->tzhead.tzh_typecnt);
int_fast32_t charcnt = detzcode(up->tzhead.tzh_charcnt);
char const *p = up->buf + tzheadsize;
if (! (0 <= leapcnt && leapcnt < TZ_MAX_LEAPS
&& 0 < typecnt && typecnt < TZ_MAX_TYPES
&& 0 <= timecnt && timecnt < TZ_MAX_TIMES
&& 0 <= charcnt && charcnt < TZ_MAX_CHARS
&& (ttisstdcnt == typecnt || ttisstdcnt == 0)
&& (ttisgmtcnt == typecnt || ttisgmtcnt == 0)))
return EINVAL;
if (nread
< (tzheadsize /* struct tzhead */
+ timecnt * stored /* ats */
+ timecnt /* types */
+ typecnt * 6 /* ttinfos */
+ charcnt /* chars */
+ leapcnt * (stored + 4) /* lsinfos */
+ ttisstdcnt /* ttisstds */
+ ttisgmtcnt)) /* ttisgmts */
return EINVAL;
sp->leapcnt = leapcnt;
sp->timecnt = timecnt;
sp->typecnt = typecnt;
sp->charcnt = charcnt;
/* Read transitions, discarding those out of time_t range.
But pretend the last transition before time_t_min
occurred at time_t_min. */
timecnt = 0;
for (i = 0; i < sp->timecnt; ++i) {
int_fast64_t at
= stored == 4 ? detzcode(p) : detzcode64(p);
sp->types[i] = at <= time_t_max;
if (sp->types[i]) {
time_t attime
= ((TYPE_SIGNED(time_t) ? at < time_t_min : at < 0)
? time_t_min : at);
if (timecnt && attime <= sp->ats[timecnt - 1]) {
if (attime < sp->ats[timecnt - 1])
return EINVAL;
sp->types[i - 1] = 0;
timecnt--;
}
sp->ats[timecnt++] = attime;
}
p += stored;
}
timecnt = 0;
for (i = 0; i < sp->timecnt; ++i) {
unsigned char typ = *p++;
if (sp->typecnt <= typ)
return EINVAL;
if (sp->types[i])
sp->types[timecnt++] = typ;
}
sp->timecnt = timecnt;
for (i = 0; i < sp->typecnt; ++i) {
register struct ttinfo * ttisp;
unsigned char isdst, abbrind;
ttisp = &sp->ttis[i];
ttisp->tt_gmtoff = detzcode(p);
p += 4;
isdst = *p++;
if (! (isdst < 2))
return EINVAL;
ttisp->tt_isdst = isdst;
abbrind = *p++;
if (! (abbrind < sp->charcnt))
return EINVAL;
ttisp->tt_abbrind = abbrind;
}
for (i = 0; i < sp->charcnt; ++i)
sp->chars[i] = *p++;
sp->chars[i] = '\0'; /* ensure '\0' at end */
/* Read leap seconds, discarding those out of time_t range. */
leapcnt = 0;
for (i = 0; i < sp->leapcnt; ++i) {
int_fast64_t tr = stored == 4 ? detzcode(p) : detzcode64(p);
int_fast32_t corr = detzcode(p + stored);
p += stored + 4;
if (tr <= time_t_max) {
time_t trans
= ((TYPE_SIGNED(time_t) ? tr < time_t_min : tr < 0)
? time_t_min : tr);
if (leapcnt && trans <= sp->lsis[leapcnt - 1].ls_trans) {
if (trans < sp->lsis[leapcnt - 1].ls_trans)
return EINVAL;
leapcnt--;
}
sp->lsis[leapcnt].ls_trans = trans;
sp->lsis[leapcnt].ls_corr = corr;
leapcnt++;
}
}
sp->leapcnt = leapcnt;
for (i = 0; i < sp->typecnt; ++i) {
register struct ttinfo * ttisp;
ttisp = &sp->ttis[i];
if (ttisstdcnt == 0)
ttisp->tt_ttisstd = false;
else {
if (*p != true && *p != false)
return EINVAL;
ttisp->tt_ttisstd = *p++;
}
}
for (i = 0; i < sp->typecnt; ++i) {
register struct ttinfo * ttisp;
ttisp = &sp->ttis[i];
if (ttisgmtcnt == 0)
ttisp->tt_ttisgmt = false;
else {
if (*p != true && *p != false)
return EINVAL;
ttisp->tt_ttisgmt = *p++;
}
}
/*
** If this is an old file, we're done.
*/
if (up->tzhead.tzh_version[0] == '\0')
break;
nread -= p - up->buf;
memmove(up->buf, p, nread);
}
if (doextend && nread > 2 &&
up->buf[0] == '\n' && up->buf[nread - 1] == '\n' &&
sp->typecnt + 2 <= TZ_MAX_TYPES) {
struct state *ts = &lsp->u.st;
up->buf[nread - 1] = '\0';
if (tzparse(&up->buf[1], ts, false)
&& ts->typecnt == 2) {
/* Attempt to reuse existing abbreviations.
Without this, America/Anchorage would stop
working after 2037 when TZ_MAX_CHARS is 50, as
sp->charcnt equals 42 (for LMT CAT CAWT CAPT AHST
AHDT YST AKDT AKST) and ts->charcnt equals 10
(for AKST AKDT). Reusing means sp->charcnt can
stay 42 in this example. */
int gotabbr = 0;
int charcnt = sp->charcnt;
for (i = 0; i < 2; i++) {
char *tsabbr = ts->chars + ts->ttis[i].tt_abbrind;
int j;
for (j = 0; j < charcnt; j++)
if (strcmp(sp->chars + j, tsabbr) == 0) {
ts->ttis[i].tt_abbrind = j;
gotabbr++;
break;
}
if (! (j < charcnt)) {
int tsabbrlen = strlen(tsabbr);
if (j + tsabbrlen < TZ_MAX_CHARS) {
strcpy(sp->chars + j, tsabbr);
charcnt = j + tsabbrlen + 1;
ts->ttis[i].tt_abbrind = j;
gotabbr++;
}
}
}
if (gotabbr == 2) {
sp->charcnt = charcnt;
for (i = 0; i < ts->timecnt; i++)
if (sp->ats[sp->timecnt - 1] < ts->ats[i])
break;
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->timecnt; ++i)
if (sp->types[i] == 0)
break;
i = i < sp->timecnt ? -1 : 0;
/*
** 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;
return 0;
}
/* Load tz data from the file named NAME into *SP. Read extended
format if DOEXTEND. Return 0 on success, an errno value on failure. */
static int
tzload(char const *name, struct state *sp, bool doextend)
{
#ifdef ALL_STATE
union local_storage *lsp = malloc(sizeof *lsp);
if (!lsp)
return errno;
else {
int err = tzloadbody(name, sp, doextend, lsp);
free(lsp);
return err;
}
#else
union local_storage ls;
return tzloadbody(name, sp, doextend, &ls);
#endif
}
static bool
typesequiv(const struct state *sp, int a, int b)
{
register bool result;
if (sp == NULL ||
a < 0 || a >= sp->typecnt ||
b < 0 || b >= sp->typecnt)
result = false;
else {
register const struct ttinfo * ap = &sp->ttis[a];
register 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 * ATTRIBUTE_PURE
getzname(register const char *strp)
{
register 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 * ATTRIBUTE_PURE
getqzname(register const char *strp, const int delim)
{
register 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(register const char *strp, int *const nump, const int min, const int max)
{
register char c;
register int num;
if (strp == NULL || !is_digit(c = *strp))
return NULL;
num = 0;
do {
num = num * 10 + (c - '0');
if (num > max)
return NULL; /* illegal value */
c = *++strp;
} while (is_digit(c));
if (num < min)
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(register 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(register const char *strp, int_fast32_t *const offsetp)
{
register bool neg = false;
if (*strp == '-') {
neg = true;
++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, register 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 a year, a rule, and the offset from UT at the time that rule takes
** effect, calculate the year-relative time that rule takes effect.
*/
static int_fast32_t ATTRIBUTE_PURE
transtime(const int year, register const struct rule *const rulep,
const int_fast32_t offset)
{
register bool leapyear;
register int_fast32_t value;
register 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 = (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 = rulep->r_day * SECSPERDAY;
break;
case MONTH_NTH_DAY_OF_WEEK:
/*
** Mm.n.d - nth "dth day" of month m.
*/
/*
** 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 = d * SECSPERDAY;
for (i = 0; i < rulep->r_mon - 1; ++i)
value += mon_lengths[leapyear][i] * SECSPERDAY;
break;
}
/*
** "value" is the year-relative time of 00:00:00 UT on the day in
** question. To get the year-relative time of the specified local
** time on that day, add the transition time and the current offset
** from UT.
*/
return value + rulep->r_time + offset;
}
/*
** Given a POSIX section 8-style TZ string, fill in the rule tables as
** appropriate.
*/
static bool
tzparse(const char *name, struct state *sp, bool lastditch)
{
const char * stdname;
const char * dstname;
size_t stdlen;
size_t dstlen;
size_t charcnt;
int_fast32_t stdoffset;
int_fast32_t dstoffset;
register char * cp;
register bool load_ok;
stdname = name;
if (lastditch) {
stdlen = sizeof gmt - 1;
name += stdlen;
stdoffset = 0;
} else {
if (*name == '<') {
name++;
stdname = name;
name = getqzname(name, '>');
if (*name != '>')
return false;
stdlen = name - stdname;
name++;
} else {
name = getzname(name);
stdlen = name - stdname;
}
if (!stdlen)
return false;
name = getoffset(name, &stdoffset);
if (name == NULL)
return false;
}
charcnt = stdlen + 1;
if (sizeof sp->chars < charcnt)
return false;
load_ok = tzload(TZDEFRULES, sp, false) == 0;
if (!load_ok)
sp->leapcnt = 0; /* so, we're off a little */
if (*name != '\0') {
if (*name == '<') {
dstname = ++name;
name = getqzname(name, '>');
if (*name != '>')
return false;
dstlen = name - dstname;
name++;
} else {
dstname = name;
name = getzname(name);
dstlen = name - dstname; /* length of DST zone name */
}
if (!dstlen)
return false;
charcnt += dstlen + 1;
if (sizeof sp->chars < charcnt)
return false;
if (*name != '\0' && *name != ',' && *name != ';') {
name = getoffset(name, &dstoffset);
if (name == NULL)
return false;
} else dstoffset = stdoffset - SECSPERHOUR;
if (*name == '\0' && !load_ok)
name = TZDEFRULESTRING;
if (*name == ',' || *name == ';') {
struct rule start;
struct rule end;
register int year;
register int yearlim;
register int timecnt;
time_t janfirst;
++name;
if ((name = getrule(name, &start)) == NULL)
return false;
if (*name++ != ',')
return false;
if ((name = getrule(name, &end)) == NULL)
return false;
if (*name != '\0')
return false;
sp->typecnt = 2; /* standard time and DST */
/*
** Two transitions per year, from EPOCH_YEAR forward.
*/
init_ttinfo(&sp->ttis[0], -dstoffset, true, stdlen + 1);
init_ttinfo(&sp->ttis[1], -stdoffset, false, 0);
sp->defaulttype = 0;
timecnt = 0;
janfirst = 0;
yearlim = EPOCH_YEAR + YEARSPERREPEAT;
for (year = EPOCH_YEAR; year < yearlim; year++) {
int_fast32_t
starttime = transtime(year, &start, stdoffset),
endtime = transtime(year, &end, dstoffset);
int_fast32_t
yearsecs = (year_lengths[isleap(year)]
* SECSPERDAY);
bool reversed = endtime < starttime;
if (reversed) {
int_fast32_t swap = starttime;
starttime = endtime;
endtime = swap;
}
if (reversed
|| (starttime < endtime
&& (endtime - starttime
< (yearsecs
+ (stdoffset - dstoffset))))) {
if (TZ_MAX_TIMES - 2 < timecnt)
break;
yearlim = year + YEARSPERREPEAT + 1;
sp->ats[timecnt] = janfirst;
if (increment_overflow_time
(&sp->ats[timecnt], starttime))
break;
sp->types[timecnt++] = reversed;
sp->ats[timecnt] = janfirst;
if (increment_overflow_time
(&sp->ats[timecnt], endtime))
break;
sp->types[timecnt++] = !reversed;
}
if (increment_overflow_time(&janfirst, yearsecs))
break;
}
sp->timecnt = timecnt;
if (!timecnt)
sp->typecnt = 1; /* Perpetual DST. */
} else {
register int_fast32_t theirstdoffset;
register int_fast32_t theirdstoffset;
register int_fast32_t theiroffset;
register bool isdst;
register int i;
register int j;
if (*name != '\0')
return false;
/*
** 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] += dstoffset -
theirdstoffset;
} else {
sp->ats[i] += stdoffset -
theirstdoffset;
}
}
theiroffset = -sp->ttis[j].tt_gmtoff;
if (sp->ttis[j].tt_isdst)
theirdstoffset = theiroffset;
else theirstdoffset = theiroffset;
}
/*
** Finally, fill in ttis.
*/
init_ttinfo(&sp->ttis[0], -stdoffset, false, 0);
init_ttinfo(&sp->ttis[1], -dstoffset, true, stdlen + 1);
sp->typecnt = 2;
sp->defaulttype = 0;
}
} else {
dstlen = 0;
sp->typecnt = 1; /* only standard time */
sp->timecnt = 0;
init_ttinfo(&sp->ttis[0], -stdoffset, false, 0);
sp->defaulttype = 0;
}
sp->charcnt = charcnt;
cp = sp->chars;
memcpy(cp, stdname, stdlen);
cp += stdlen;
*cp++ = '\0';
if (dstlen != 0) {
memcpy(cp, dstname, dstlen);
*(cp + dstlen) = '\0';
}
return true;
}
static void
gmtload(struct state *const sp)
{
if (tzload(gmt, sp, true) != 0)
tzparse(gmt, sp, true);
}
/* Initialize *SP to a value appropriate for the TZ setting NAME.
Return 0 on success, an errno value on failure. */
static int
zoneinit(struct state *sp, char const *name)
{
if (name && ! name[0]) {
/*
** User wants it fast rather than right.
*/
sp->leapcnt = 0; /* so, we're off a little */
sp->timecnt = 0;
sp->typecnt = 0;
sp->charcnt = 0;
sp->goback = sp->goahead = false;
init_ttinfo(&sp->ttis[0], 0, false, 0);
strcpy(sp->chars, gmt);
sp->defaulttype = 0;
return 0;
} else {
int err = tzload(name, sp, true);
if (err != 0 && name && name[0] != ':' && tzparse(name, sp, false))
err = 0;
if (err == 0)
scrub_abbrs(sp);
return err;
}
}
static void
tzsetlcl(char const *name)
{
struct state *sp = lclptr;
int lcl = name ? strlen(name) < sizeof lcl_TZname : -1;
if (lcl < 0
? lcl_is_set < 0
: 0 < lcl_is_set && strcmp(lcl_TZname, name) == 0)
return;
#ifdef ALL_STATE
if (! sp)
lclptr = sp = malloc(sizeof *lclptr);
#endif /* defined ALL_STATE */
if (sp) {
if (zoneinit(sp, name) != 0)
zoneinit(sp, "");
if (0 < lcl)
strcpy(lcl_TZname, name);
}
settzname();
lcl_is_set = lcl;
}
#ifdef STD_INSPIRED
void
tzsetwall(void)
{
if (lock() != 0)
return;
tzsetlcl(NULL);
unlock();
}
#endif
#if defined(__ANDROID__)
#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
#include <sys/_system_properties.h> // For __system_property_serial.
#endif
static void
tzset_unlocked(void)
{
#if defined(__ANDROID__)
// The TZ environment variable is meant to override the system-wide setting.
const char * name = getenv("TZ");
// If that's not set, look at the "persist.sys.timezone" system property.
if (name == NULL) {
static const prop_info *pi;
if (!pi) {
pi = __system_property_find("persist.sys.timezone");
}
if (pi) {
static char buf[PROP_VALUE_MAX];
static uint32_t s = -1;
static bool ok = false;
uint32_t serial = __system_property_serial(pi);
if (serial != s) {
ok = __system_property_read(pi, 0, buf) > 0;
s = serial;
}
if (ok) {
name = buf;
}
}
}
// If that's not available (because you're running AOSP on a WiFi-only
// device, say), fall back to GMT.
if (name == NULL) name = gmt;
tzsetlcl(name);
#else
tzsetlcl(getenv("TZ"));
#endif
}
void
tzset(void)
{
if (lock() != 0)
return;
tzset_unlocked();
unlock();
}
static void
gmtcheck(void)
{
static bool gmt_is_set;
if (lock() != 0)
return;
if (! gmt_is_set) {
#ifdef ALL_STATE
gmtptr = malloc(sizeof *gmtptr);
#endif
if (gmtptr)
gmtload(gmtptr);
gmt_is_set = true;
}
unlock();
}
#if NETBSD_INSPIRED
timezone_t
tzalloc(char const *name)
{
timezone_t sp = malloc(sizeof *sp);
if (sp) {
int err = zoneinit(sp, name);
if (err != 0) {
free(sp);
errno = err;
return NULL;
}
}
return sp;
}
void
tzfree(timezone_t sp)
{
free(sp);
}
/*
** NetBSD 6.1.4 has ctime_rz, but omit it because POSIX says ctime and
** ctime_r are obsolescent and have potential security problems that
** ctime_rz would share. Callers can instead use localtime_rz + strftime.
**
** NetBSD 6.1.4 has tzgetname, but omit it because it doesn't work
** in zones with three or more time zone abbreviations.
** Callers can instead use localtime_rz + strftime.
*/
#endif
/*
** 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.)
**
** If successful and SETNAME is nonzero,
** set the applicable parts of tzname, timezone and altzone;
** however, it's OK to omit this step if the time zone is POSIX-compatible,
** since in that case tzset should have already done this step correctly.
** SETNAME's type is intfast32_t for compatibility with gmtsub,
** but it is actually a boolean and its value should be 0 or 1.
*/
/*ARGSUSED*/
static struct tm *
localsub(struct state const *sp, time_t const *timep, int_fast32_t setname,
struct tm *const tmp)
{
register const struct ttinfo * ttisp;
register int i;
register struct tm * result;
const time_t t = *timep;
if (sp == NULL) {
/* Don't bother to set tzname etc.; tzset has already done it. */
return gmtsub(gmtptr, timep, 0, tmp);
}
if ((sp->goback && t < sp->ats[0]) ||
(sp->goahead && t > sp->ats[sp->timecnt - 1])) {
time_t newt = t;
register time_t seconds;
register time_t years;
if (t < sp->ats[0])
seconds = sp->ats[0] - t;
else seconds = t - sp->ats[sp->timecnt - 1];
--seconds;
years = (seconds / SECSPERREPEAT + 1) * YEARSPERREPEAT;
seconds = 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, setname, tmp);
if (result) {
register int_fast64_t newy;
newy = result->tm_year;
if (t < sp->ats[0])
newy -= years;
else newy += years;
if (! (INT_MIN <= newy && newy <= INT_MAX))
return NULL;
result->tm_year = newy;
}
return result;
}
if (sp->timecnt == 0 || t < sp->ats[0]) {
i = sp->defaulttype;
} else {
register int lo = 1;
register int hi = sp->timecnt;
while (lo < hi) {
register int mid = (lo + hi) >> 1;
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(&t, ttisp->tt_gmtoff, sp, tmp);
if (result) {
result->tm_isdst = ttisp->tt_isdst;
#ifdef TM_ZONE
result->TM_ZONE = (char *) &sp->chars[ttisp->tt_abbrind];
#endif /* defined TM_ZONE */
if (setname)
update_tzname_etc(sp, ttisp);
}
return result;
}
#if NETBSD_INSPIRED
struct tm *
localtime_rz(struct state *sp, time_t const *timep, struct tm *tmp)
{
return localsub(sp, timep, 0, tmp);
}
#endif
static struct tm *
localtime_tzset(time_t const *timep, struct tm *tmp, bool setname)
{
int err = lock();
if (err) {
errno = err;
return NULL;
}
if (setname || !lcl_is_set)
tzset_unlocked();
tmp = localsub(lclptr, timep, setname, tmp);
unlock();
return tmp;
}
struct tm *
localtime(const time_t *timep)
{
return localtime_tzset(timep, &tm, true);
}
struct tm *
localtime_r(const time_t *timep, struct tm *tmp)
{
return localtime_tzset(timep, tmp, false);
}
/*
** gmtsub is to gmtime as localsub is to localtime.
*/
static struct tm *
gmtsub(struct state const *sp, time_t const *timep, int_fast32_t offset,
struct tm *tmp)
{
register struct tm * result;
result = timesub(timep, offset, gmtptr, 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.
*/
tmp->TM_ZONE = ((char *)
(offset ? wildabbr : gmtptr ? gmtptr->chars : gmt));
#endif /* defined TM_ZONE */
return result;
}
/*
* Re-entrant version of gmtime.
*/
struct tm *
gmtime_r(const time_t *timep, struct tm *tmp)
{
gmtcheck();
return gmtsub(gmtptr, timep, 0, tmp);
}
struct tm *
gmtime(const time_t *timep)
{
return gmtime_r(timep, &tm);
}
#ifdef STD_INSPIRED
struct tm *
offtime(const time_t *timep, long offset)
{
gmtcheck();
return gmtsub(gmtptr, timep, offset, &tm);
}
#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 ATTRIBUTE_PURE
leaps_thru_end_of(register const int y)
{
return (y >= 0) ? (y / 4 - y / 100 + y / 400) :
-(leaps_thru_end_of(-(y + 1)) + 1);
}
static struct tm *
timesub(const time_t *timep, int_fast32_t offset,
const struct state *sp, struct tm *tmp)
{
register const struct lsinfo * lp;
register time_t tdays;
register int idays; /* unsigned would be so 2003 */
register int_fast64_t rem;
int y;
register const int * ip;
register int_fast64_t corr;
register bool hit;
register int i;
corr = 0;
hit = false;
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 = *timep / SECSPERDAY;
rem = *timep % SECSPERDAY;
while (tdays < 0 || tdays >= year_lengths[isleap(y)]) {
int newy;
register time_t tdelta;
register int idelta;
register int leapdays;
tdelta = tdays / DAYSPERLYEAR;
if (! ((! TYPE_SIGNED(time_t) || INT_MIN <= tdelta)
&& tdelta <= INT_MAX))
goto out_of_range;
idelta = tdelta;
if (idelta == 0)
idelta = (tdays < 0) ? -1 : 1;
newy = y;
if (increment_overflow(&newy, idelta))
goto out_of_range;
leapdays = leaps_thru_end_of(newy - 1) -
leaps_thru_end_of(y - 1);
tdays -= ((time_t) newy - y) * DAYSPERNYEAR;
tdays -= leapdays;
y = newy;
}
/*
** Given the range, we can now fearlessly cast...
*/
idays = tdays;
rem += offset - corr;
while (rem < 0) {
rem += SECSPERDAY;
--idays;
}
while (rem >= SECSPERDAY) {
rem -= SECSPERDAY;
++idays;
}
while (idays < 0) {
if (increment_overflow(&y, -1))
goto out_of_range;
idays += year_lengths[isleap(y)];
}
while (idays >= year_lengths[isleap(y)]) {
idays -= year_lengths[isleap(y)];
if (increment_overflow(&y, 1))
goto out_of_range;
}
tmp->tm_year = y;
if (increment_overflow(&tmp->tm_year, -TM_YEAR_BASE))
goto out_of_range;
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;
out_of_range:
errno = EOVERFLOW;
return NULL;
}
char *
ctime(const time_t *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 *tmp = localtime(timep);
return tmp ? asctime(tmp) : NULL;
}
char *
ctime_r(const time_t *timep, char *buf)
{
struct tm mytm;
struct tm *tmp = localtime_r(timep, &mytm);
return tmp ? asctime_r(tmp, buf) : NULL;
}
/*
** 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 (-1)
#endif /* !defined WRONG */
/*
** Normalize logic courtesy Paul Eggert.
*/
static bool
increment_overflow(int *ip, int j)
{
register int const 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 bool
increment_overflow32(int_fast32_t *const lp, int const m)
{
register int_fast32_t const l = *lp;
if ((l >= 0) ? (m > INT_FAST32_MAX - l) : (m < INT_FAST32_MIN - l))
return true;
*lp += m;
return false;
}
static bool
increment_overflow_time(time_t *tp, int_fast32_t j)
{
/*
** This is like
** 'if (! (time_t_min <= *tp + j && *tp + j <= time_t_max)) ...',
** except that it does the right thing even if *tp + j would overflow.
*/
if (! (j < 0
? (TYPE_SIGNED(time_t) ? time_t_min - j <= *tp : -1 - j < *tp)
: *tp <= time_t_max - j))
return true;
*tp += j;
return false;
}
static bool
normalize_overflow(int *const tensptr, int *const unitsptr, const int base)
{
register int tensdelta;
tensdelta = (*unitsptr >= 0) ?
(*unitsptr / base) :
(-1 - (-1 - *unitsptr) / base);
*unitsptr -= tensdelta * base;
return increment_overflow(tensptr, tensdelta);
}
static bool
normalize_overflow32(int_fast32_t *tensptr, int *unitsptr, int base)
{
register int tensdelta;
tensdelta = (*unitsptr >= 0) ?
(*unitsptr / base) :
(-1 - (-1 - *unitsptr) / base);
*unitsptr -= tensdelta * base;
return increment_overflow32(tensptr, tensdelta);
}
static int
tmcomp(register const struct tm *const atmp,
register const struct tm *const btmp)
{
register 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(struct tm *const tmp,
struct tm *(*funcp)(struct state const *, time_t const *,
int_fast32_t, struct tm *),
struct state const *sp,
const int_fast32_t offset,
bool *okayp,
bool do_norm_secs)
{
register int dir;
register int i, j;
register int saved_seconds;
register int_fast32_t li;
register time_t lo;
register time_t hi;
int_fast32_t y;
time_t newt;
time_t t;
struct tm yourtm, mytm;
*okayp = false;
yourtm = *tmp;
if (do_norm_secs) {
if (normalize_overflow(&yourtm.tm_min, &yourtm.tm_sec,
SECSPERMIN))
return WRONG;
}
if (normalize_overflow(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR))
return WRONG;
if (normalize_overflow(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY))
return WRONG;
y = yourtm.tm_year;
if (normalize_overflow32(&y, &yourtm.tm_mon, MONSPERYEAR))
return WRONG;
/*
** 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))
return WRONG;
while (yourtm.tm_mday <= 0) {
if (increment_overflow32(&y, -1))
return WRONG;
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))
return WRONG;
}
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))
return WRONG;
}
}
if (increment_overflow32(&y, -TM_YEAR_BASE))
return WRONG;
if (! (INT_MIN <= y && y <= INT_MAX))
return WRONG;
yourtm.tm_year = y;
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))
return WRONG;
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).
*/
lo = time_t_min;
hi = time_t_max;
for ( ; ; ) {
t = lo / 2 + hi / 2;
if (t < lo)
t = lo;
else if (t > hi)
t = hi;
if (! funcp(sp, &t, offset, &mytm)) {
/*
** 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)
return WRONG;
++t;
++lo;
} else if (t == hi) {
if (t == time_t_min)
return WRONG;
--t;
--hi;
}
if (lo > hi)
return WRONG;
if (dir > 0)
hi = t;
else lo = t;
continue;
}
#if defined TM_GMTOFF && ! UNINIT_TRAP
if (mytm.TM_GMTOFF != yourtm.TM_GMTOFF
&& (yourtm.TM_GMTOFF < 0
? (-SECSPERDAY <= yourtm.TM_GMTOFF
&& (mytm.TM_GMTOFF <=
(SMALLEST (INT_FAST32_MAX, LONG_MAX)
+ yourtm.TM_GMTOFF)))
: (yourtm.TM_GMTOFF <= SECSPERDAY
&& ((BIGGEST (INT_FAST32_MIN, LONG_MIN)
+ yourtm.TM_GMTOFF)
<= mytm.TM_GMTOFF)))) {
/* MYTM matches YOURTM except with the wrong UTC offset.
YOURTM.TM_GMTOFF is plausible, so try it instead.
It's OK if YOURTM.TM_GMTOFF contains uninitialized data,
since the guess gets checked. */
time_t altt = t;
int_fast32_t diff = mytm.TM_GMTOFF - yourtm.TM_GMTOFF;
if (!increment_overflow_time(&altt, diff)) {
struct tm alttm;
if (funcp(sp, &altt, offset, &alttm)
&& alttm.tm_isdst == mytm.tm_isdst
&& alttm.TM_GMTOFF == yourtm.TM_GMTOFF
&& tmcomp(&alttm, &yourtm) == 0) {
t = altt;
mytm = alttm;
}
}
}
#endif
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)
return WRONG;
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 = t + sp->ttis[j].tt_gmtoff -
sp->ttis[i].tt_gmtoff;
if (! funcp(sp, &newt, offset, &mytm))
continue;
if (tmcomp(&mytm, &yourtm) != 0)
continue;
if (mytm.tm_isdst != yourtm.tm_isdst)
continue;
/*
** We have a match.
*/
t = newt;
goto label;
}
}
return WRONG;
}
label:
newt = t + saved_seconds;
if ((newt < t) != (saved_seconds < 0))
return WRONG;
t = newt;
if (funcp(sp, &t, offset, tmp))
*okayp = true;
return t;
}
static time_t
time2(struct tm * const tmp,
struct tm *(*funcp)(struct state const *, time_t const *,
int_fast32_t, struct tm *),
struct state const *sp,
const int_fast32_t offset,
bool *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(tmp, funcp, sp, offset, okayp, false);
return *okayp ? t : time2sub(tmp, funcp, sp, offset, okayp, true);
}
static time_t
time1(struct tm *const tmp,
struct tm *(*funcp) (struct state const *, time_t const *,
int_fast32_t, struct tm *),
struct state const *sp,
const int_fast32_t offset)
{
register time_t t;
register int samei, otheri;
register int sameind, otherind;
register int i;
register int nseen;
char seen[TZ_MAX_TYPES];
unsigned char types[TZ_MAX_TYPES];
bool okay;
if (tmp == NULL) {
errno = EINVAL;
return WRONG;
}
if (tmp->tm_isdst > 1)
tmp->tm_isdst = 1;
t = time2(tmp, funcp, sp, offset, &okay);
if (okay)
return t;
if (tmp->tm_isdst < 0)
#ifdef PCTS
/*
** POSIX Conformance Test Suite code courtesy Grant Sullivan.
*/
tmp->tm_isdst = 0; /* reset to std and try again */
#else
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)
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 += sp->ttis[otheri].tt_gmtoff -
sp->ttis[samei].tt_gmtoff;
tmp->tm_isdst = !tmp->tm_isdst;
t = time2(tmp, funcp, sp, offset, &okay);
if (okay)
return t;
tmp->tm_sec -= sp->ttis[otheri].tt_gmtoff -
sp->ttis[samei].tt_gmtoff;
tmp->tm_isdst = !tmp->tm_isdst;
}
}
return WRONG;
}
static time_t
mktime_tzname(struct state *sp, struct tm *tmp, bool setname)
{
if (sp)
return time1(tmp, localsub, sp, setname);
else {
gmtcheck();
return time1(tmp, gmtsub, gmtptr, 0);
}
}
#if NETBSD_INSPIRED
time_t
mktime_z(struct state *sp, struct tm *tmp)
{
return mktime_tzname(sp, tmp, false);
}
#endif
time_t
mktime(struct tm *tmp)
{
time_t t;
int err = lock();
if (err) {
errno = err;
return -1;
}
tzset_unlocked();
t = mktime_tzname(lclptr, tmp, true);
unlock();
return t;
}
#ifdef STD_INSPIRED
time_t
timelocal(struct tm *tmp)
{
if (tmp != NULL)
tmp->tm_isdst = -1; /* in case it wasn't initialized */
return mktime(tmp);
}
time_t
timegm(struct tm *tmp)
{
return timeoff(tmp, 0);
}
time_t
timeoff(struct tm *tmp, long offset)
{
if (tmp)
tmp->tm_isdst = 0;
gmtcheck();
return time1(tmp, gmtsub, gmtptr, offset);
}
#endif /* defined STD_INSPIRED */
/*
** 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(struct state const *sp, time_t t)
{
register struct lsinfo const * lp;
register int i;
i = sp->leapcnt;
while (--i >= 0) {
lp = &sp->lsis[i];
if (t >= lp->ls_trans)
return lp->ls_corr;
}
return 0;
}
NETBSD_INSPIRED_EXTERN time_t ATTRIBUTE_PURE
time2posix_z(struct state *sp, time_t t)
{
return t - leapcorr(sp, t);
}
time_t
time2posix(time_t t)
{
int err = lock();
if (err) {
errno = err;
return -1;
}
if (!lcl_is_set)
tzset_unlocked();
if (lclptr)
t = time2posix_z(lclptr, t);
unlock();
return t;
}
NETBSD_INSPIRED_EXTERN time_t ATTRIBUTE_PURE
posix2time_z(struct state *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 = t + leapcorr(sp, t);
y = x - leapcorr(sp, x);
if (y < t) {
do {
x++;
y = x - leapcorr(sp, x);
} while (y < t);
x -= y != t;
} else if (y > t) {
do {
--x;
y = x - leapcorr(sp, x);
} while (y > t);
x += y != t;
}
return x;
}
time_t
posix2time(time_t t)
{
int err = lock();
if (err) {
errno = err;
return -1;
}
if (!lcl_is_set)
tzset_unlocked();
if (lclptr)
t = posix2time_z(lclptr, t);
unlock();
return t;
}
#endif /* defined STD_INSPIRED */
#ifdef time_tz
/* Convert from the underlying system's time_t to the ersatz time_tz,
which is called 'time_t' in this file. */
time_t
time(time_t *p)
{
time_t r = sys_time(0);
if (p)
*p = r;
return r;
}
#endif
// BEGIN android-added
#include <assert.h>
#include <stdint.h>
#include <arpa/inet.h> // For ntohl(3).
static int __bionic_open_tzdata_path(const char* path_prefix_variable, const char* path_suffix,
const char* olson_id) {
const char* path_prefix = getenv(path_prefix_variable);
if (path_prefix == NULL) {
fprintf(stderr, "%s: %s not set!\n", __FUNCTION__, path_prefix_variable);
return -1;
}
size_t path_length = strlen(path_prefix) + 1 + strlen(path_suffix) + 1;
char* path = malloc(path_length);
if (path == NULL) {
fprintf(stderr, "%s: couldn't allocate %zu-byte path\n", __FUNCTION__, path_length);
return -1;
}
snprintf(path, path_length, "%s/%s", path_prefix, path_suffix);
int fd = TEMP_FAILURE_RETRY(open(path, OPEN_MODE));
if (fd == -1) {
free(path);
return -2; // Distinguish failure to find any data from failure to find a specific id.
}
// byte[12] tzdata_version -- "tzdata2012f\0"
// int index_offset
// int data_offset
// int zonetab_offset
struct bionic_tzdata_header {
char tzdata_version[12];
int32_t index_offset;
int32_t data_offset;
int32_t zonetab_offset;
} header;
memset(&header, 0, sizeof(header));
ssize_t bytes_read = TEMP_FAILURE_RETRY(read(fd, &header, sizeof(header)));
if (bytes_read != sizeof(header)) {
fprintf(stderr, "%s: could not read header of \"%s\": %s\n",
__FUNCTION__, path, (bytes_read == -1) ? strerror(errno) : "short read");
free(path);
close(fd);
return -1;
}
if (strncmp(header.tzdata_version, "tzdata", 6) != 0 || header.tzdata_version[11] != 0) {
fprintf(stderr, "%s: bad magic in \"%s\": \"%.6s\"\n",
__FUNCTION__, path, header.tzdata_version);
free(path);
close(fd);
return -1;
}
#if 0
fprintf(stderr, "version: %s\n", header.tzdata_version);
fprintf(stderr, "index_offset = %d\n", ntohl(header.index_offset));
fprintf(stderr, "data_offset = %d\n", ntohl(header.data_offset));
fprintf(stderr, "zonetab_offset = %d\n", ntohl(header.zonetab_offset));
#endif
if (TEMP_FAILURE_RETRY(lseek(fd, ntohl(header.index_offset), SEEK_SET)) == -1) {
fprintf(stderr, "%s: couldn't seek to index in \"%s\": %s\n",
__FUNCTION__, path, strerror(errno));
free(path);
close(fd);
return -1;
}
off_t specific_zone_offset = -1;
ssize_t index_size = ntohl(header.data_offset) - ntohl(header.index_offset);
char* index = malloc(index_size);
if (index == NULL) {
fprintf(stderr, "%s: couldn't allocate %zd-byte index for \"%s\"\n",
__FUNCTION__, index_size, path);
free(path);
close(fd);
return -1;
}
if (TEMP_FAILURE_RETRY(read(fd, index, index_size)) != index_size) {
fprintf(stderr, "%s: could not read index of \"%s\": %s\n",
__FUNCTION__, path, (bytes_read == -1) ? strerror(errno) : "short read");
free(path);
free(index);
close(fd);
return -1;
}
static const size_t NAME_LENGTH = 40;
struct index_entry_t {
char buf[NAME_LENGTH];
int32_t start;
int32_t length;
int32_t unused; // Was raw GMT offset; always 0 since tzdata2014f (L).
};
size_t id_count = (ntohl(header.data_offset) - ntohl(header.index_offset)) / sizeof(struct index_entry_t);
struct index_entry_t* entry = (struct index_entry_t*) index;
for (size_t i = 0; i < id_count; ++i) {
char this_id[NAME_LENGTH + 1];
memcpy(this_id, entry->buf, NAME_LENGTH);
this_id[NAME_LENGTH] = '\0';
if (strcmp(this_id, olson_id) == 0) {
specific_zone_offset = ntohl(entry->start) + ntohl(header.data_offset);
break;
}
++entry;
}
free(index);
if (specific_zone_offset == -1) {
free(path);
close(fd);
return -1;
}
if (TEMP_FAILURE_RETRY(lseek(fd, specific_zone_offset, SEEK_SET)) == -1) {
fprintf(stderr, "%s: could not seek to %ld in \"%s\": %s\n",
__FUNCTION__, specific_zone_offset, path, strerror(errno));
free(path);
close(fd);
return -1;
}
// TODO: check that there's TZ_MAGIC at this offset, so we can fall back to the other file if not.
free(path);
return fd;
}
static int __bionic_open_tzdata(const char* olson_id) {
int fd = __bionic_open_tzdata_path("ANDROID_DATA", "/misc/zoneinfo/current/tzdata", olson_id);
if (fd < 0) {
fd = __bionic_open_tzdata_path("ANDROID_ROOT", "/usr/share/zoneinfo/tzdata", olson_id);
if (fd == -2) {
// The first thing that 'recovery' does is try to format the current time. It doesn't have
// any tzdata available, so we must not abort here --- doing so breaks the recovery image!
fprintf(stderr, "%s: couldn't find any tzdata when looking for %s!\n", __FUNCTION__, olson_id);
}
}
return fd;
}
// END android-added
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