OVMS3/OVMS.V3/components/duktape/src-input/duk_bi_date_unix.c

326 lines
12 KiB
C
Raw Normal View History

/*
* Unix-like Date providers
*
* Generally useful Unix / POSIX / ANSI Date providers.
*/
#include "duk_internal.h"
/* The necessary #includes are in place in duk_config.h. */
/* Buffer sizes for some UNIX calls. Larger than strictly necessary
* to avoid Valgrind errors.
*/
#define DUK__STRPTIME_BUF_SIZE 64
#define DUK__STRFTIME_BUF_SIZE 64
#if defined(DUK_USE_DATE_NOW_GETTIMEOFDAY)
/* Get current ECMAScript time (= UNIX/Posix time, but in milliseconds). */
DUK_INTERNAL duk_double_t duk_bi_date_get_now_gettimeofday(void) {
struct timeval tv;
duk_double_t d;
if (gettimeofday(&tv, NULL) != 0) {
DUK_D(DUK_DPRINT("gettimeofday() failed"));
return 0.0;
}
/* As of Duktape 2.2.0 allow fractions. */
d = ((duk_double_t) tv.tv_sec) * 1000.0 +
((duk_double_t) tv.tv_usec) / 1000.0;
return d;
}
#endif /* DUK_USE_DATE_NOW_GETTIMEOFDAY */
#if defined(DUK_USE_DATE_NOW_TIME)
/* Not a very good provider: only full seconds are available. */
DUK_INTERNAL duk_double_t duk_bi_date_get_now_time(void) {
time_t t;
t = time(NULL);
if (t == (time_t) -1) {
DUK_D(DUK_DPRINT("time() failed"));
return 0.0;
}
return ((duk_double_t) t) * 1000.0;
}
#endif /* DUK_USE_DATE_NOW_TIME */
#if defined(DUK_USE_DATE_TZO_GMTIME) || defined(DUK_USE_DATE_TZO_GMTIME_R) || defined(DUK_USE_DATE_TZO_GMTIME_S)
/* Get local time offset (in seconds) for a certain (UTC) instant 'd'. */
DUK_INTERNAL duk_int_t duk_bi_date_get_local_tzoffset_gmtime(duk_double_t d) {
time_t t, t1, t2;
duk_int_t parts[DUK_DATE_IDX_NUM_PARTS];
duk_double_t dparts[DUK_DATE_IDX_NUM_PARTS];
struct tm tms[2];
#if defined(DUK_USE_DATE_TZO_GMTIME)
struct tm *tm_ptr;
#endif
/* For NaN/inf, the return value doesn't matter. */
if (!DUK_ISFINITE(d)) {
return 0;
}
/* If not within ECMAScript range, some integer time calculations
* won't work correctly (and some asserts will fail), so bail out
* if so. This fixes test-bug-date-insane-setyear.js. There is
* a +/- 24h leeway in this range check to avoid a test262 corner
* case documented in test-bug-date-timeval-edges.js.
*/
if (!duk_bi_date_timeval_in_leeway_range(d)) {
DUK_DD(DUK_DDPRINT("timeval not within valid range, skip tzoffset computation to avoid integer overflows"));
return 0;
}
/*
* This is a bit tricky to implement portably. The result depends
* on the timestamp (specifically, DST depends on the timestamp).
* If e.g. UNIX APIs are used, they'll have portability issues with
* very small and very large years.
*
* Current approach:
*
* - Stay within portable UNIX limits by using equivalent year mapping.
* Avoid year 1970 and 2038 as some conversions start to fail, at
* least on some platforms. Avoiding 1970 means that there are
* currently DST discrepancies for 1970.
*
* - Create a UTC and local time breakdowns from 't'. Then create
* a time_t using gmtime() and localtime() and compute the time
* difference between the two.
*
* Equivalent year mapping (E5 Section 15.9.1.8):
*
* If the host environment provides functionality for determining
* daylight saving time, the implementation of ECMAScript is free
* to map the year in question to an equivalent year (same
* leap-year-ness and same starting week day for the year) for which
* the host environment provides daylight saving time information.
* The only restriction is that all equivalent years should produce
* the same result.
*
* This approach is quite reasonable but not entirely correct, e.g.
* the specification also states (E5 Section 15.9.1.8):
*
* The implementation of ECMAScript should not try to determine
* whether the exact time was subject to daylight saving time, but
* just whether daylight saving time would have been in effect if
* the _current daylight saving time algorithm_ had been used at the
* time. This avoids complications such as taking into account the
* years that the locale observed daylight saving time year round.
*
* Since we rely on the platform APIs for conversions between local
* time and UTC, we can't guarantee the above. Rather, if the platform
* has historical DST rules they will be applied. This seems to be the
* general preferred direction in ECMAScript standardization (or at least
* implementations) anyway, and even the equivalent year mapping should
* be disabled if the platform is known to handle DST properly for the
* full ECMAScript range.
*
* The following has useful discussion and links:
*
* https://bugzilla.mozilla.org/show_bug.cgi?id=351066
*/
duk_bi_date_timeval_to_parts(d, parts, dparts, DUK_DATE_FLAG_EQUIVYEAR /*flags*/);
DUK_ASSERT(parts[DUK_DATE_IDX_YEAR] >= 1970 && parts[DUK_DATE_IDX_YEAR] <= 2038);
d = duk_bi_date_get_timeval_from_dparts(dparts, 0 /*flags*/);
DUK_ASSERT(d >= 0 && d < 2147483648.0 * 1000.0); /* unsigned 31-bit range */
t = (time_t) (d / 1000.0);
DUK_DDD(DUK_DDDPRINT("timeval: %lf -> time_t %ld", (double) d, (long) t));
duk_memzero((void *) tms, sizeof(struct tm) * 2);
#if defined(DUK_USE_DATE_TZO_GMTIME_R)
(void) gmtime_r(&t, &tms[0]);
(void) localtime_r(&t, &tms[1]);
#elif defined(DUK_USE_DATE_TZO_GMTIME_S)
(void) gmtime_s(&t, &tms[0]);
(void) localtime_s(&t, &tms[1]);
#elif defined(DUK_USE_DATE_TZO_GMTIME)
tm_ptr = gmtime(&t);
duk_memcpy((void *) &tms[0], tm_ptr, sizeof(struct tm));
tm_ptr = localtime(&t);
duk_memcpy((void *) &tms[1], tm_ptr, sizeof(struct tm));
#else
#error internal error
#endif
DUK_DDD(DUK_DDDPRINT("gmtime result: tm={sec:%ld,min:%ld,hour:%ld,mday:%ld,mon:%ld,year:%ld,"
"wday:%ld,yday:%ld,isdst:%ld}",
(long) tms[0].tm_sec, (long) tms[0].tm_min, (long) tms[0].tm_hour,
(long) tms[0].tm_mday, (long) tms[0].tm_mon, (long) tms[0].tm_year,
(long) tms[0].tm_wday, (long) tms[0].tm_yday, (long) tms[0].tm_isdst));
DUK_DDD(DUK_DDDPRINT("localtime result: tm={sec:%ld,min:%ld,hour:%ld,mday:%ld,mon:%ld,year:%ld,"
"wday:%ld,yday:%ld,isdst:%ld}",
(long) tms[1].tm_sec, (long) tms[1].tm_min, (long) tms[1].tm_hour,
(long) tms[1].tm_mday, (long) tms[1].tm_mon, (long) tms[1].tm_year,
(long) tms[1].tm_wday, (long) tms[1].tm_yday, (long) tms[1].tm_isdst));
/* tm_isdst is both an input and an output to mktime(), use 0 to
* avoid DST handling in mktime():
* - https://github.com/svaarala/duktape/issues/406
* - http://stackoverflow.com/questions/8558919/mktime-and-tm-isdst
*/
tms[0].tm_isdst = 0;
tms[1].tm_isdst = 0;
t1 = mktime(&tms[0]); /* UTC */
t2 = mktime(&tms[1]); /* local */
if (t1 == (time_t) -1 || t2 == (time_t) -1) {
/* This check used to be for (t < 0) but on some platforms
* time_t is unsigned and apparently the proper way to detect
* an mktime() error return is the cast above. See e.g.:
* http://pubs.opengroup.org/onlinepubs/009695299/functions/mktime.html
*/
goto mktime_error;
}
DUK_DDD(DUK_DDDPRINT("t1=%ld (utc), t2=%ld (local)", (long) t1, (long) t2));
/* Compute final offset in seconds, positive if local time ahead of
* UTC (returned value is UTC-to-local offset).
*
* difftime() returns a double, so coercion to int generates quite
* a lot of code. Direct subtraction is not portable, however.
* XXX: allow direct subtraction on known platforms.
*/
#if 0
return (duk_int_t) (t2 - t1);
#endif
return (duk_int_t) difftime(t2, t1);
mktime_error:
/* XXX: return something more useful, so that caller can throw? */
DUK_D(DUK_DPRINT("mktime() failed, d=%lf", (double) d));
return 0;
}
#endif /* DUK_USE_DATE_TZO_GMTIME */
#if defined(DUK_USE_DATE_PRS_STRPTIME)
DUK_INTERNAL duk_bool_t duk_bi_date_parse_string_strptime(duk_hthread *thr, const char *str) {
struct tm tm;
time_t t;
char buf[DUK__STRPTIME_BUF_SIZE];
/* Copy to buffer with slack to avoid Valgrind gripes from strptime. */
DUK_ASSERT(str != NULL);
duk_memzero(buf, sizeof(buf)); /* valgrind whine without this */
DUK_SNPRINTF(buf, sizeof(buf), "%s", (const char *) str);
buf[sizeof(buf) - 1] = (char) 0;
DUK_DDD(DUK_DDDPRINT("parsing: '%s'", (const char *) buf));
duk_memzero(&tm, sizeof(tm));
if (strptime((const char *) buf, "%c", &tm) != NULL) {
DUK_DDD(DUK_DDDPRINT("before mktime: tm={sec:%ld,min:%ld,hour:%ld,mday:%ld,mon:%ld,year:%ld,"
"wday:%ld,yday:%ld,isdst:%ld}",
(long) tm.tm_sec, (long) tm.tm_min, (long) tm.tm_hour,
(long) tm.tm_mday, (long) tm.tm_mon, (long) tm.tm_year,
(long) tm.tm_wday, (long) tm.tm_yday, (long) tm.tm_isdst));
tm.tm_isdst = -1; /* negative: dst info not available */
t = mktime(&tm);
DUK_DDD(DUK_DDDPRINT("mktime() -> %ld", (long) t));
if (t >= 0) {
duk_push_number(thr, ((duk_double_t) t) * 1000.0);
return 1;
}
}
return 0;
}
#endif /* DUK_USE_DATE_PRS_STRPTIME */
#if defined(DUK_USE_DATE_PRS_GETDATE)
DUK_INTERNAL duk_bool_t duk_bi_date_parse_string_getdate(duk_hthread *thr, const char *str) {
struct tm tm;
duk_small_int_t rc;
time_t t;
/* For this to work, DATEMSK must be set, so this is not very
* convenient for an embeddable interpreter.
*/
duk_memzero(&tm, sizeof(struct tm));
rc = (duk_small_int_t) getdate_r(str, &tm);
DUK_DDD(DUK_DDDPRINT("getdate_r() -> %ld", (long) rc));
if (rc == 0) {
t = mktime(&tm);
DUK_DDD(DUK_DDDPRINT("mktime() -> %ld", (long) t));
if (t >= 0) {
duk_push_number(thr, (duk_double_t) t);
return 1;
}
}
return 0;
}
#endif /* DUK_USE_DATE_PRS_GETDATE */
#if defined(DUK_USE_DATE_FMT_STRFTIME)
DUK_INTERNAL duk_bool_t duk_bi_date_format_parts_strftime(duk_hthread *thr, duk_int_t *parts, duk_int_t tzoffset, duk_small_uint_t flags) {
char buf[DUK__STRFTIME_BUF_SIZE];
struct tm tm;
const char *fmt;
DUK_UNREF(tzoffset);
/* If the platform doesn't support the entire ECMAScript range, we need
* to return 0 so that the caller can fall back to the default formatter.
*
* For now, assume that if time_t is 8 bytes or more, the whole ECMAScript
* range is supported. For smaller time_t values (4 bytes in practice),
* assumes that the signed 32-bit range is supported.
*
* XXX: detect this more correctly per platform. The size of time_t is
* probably not an accurate guarantee of strftime() supporting or not
* supporting a large time range (the full ECMAScript range).
*/
if (sizeof(time_t) < 8 &&
(parts[DUK_DATE_IDX_YEAR] < 1970 || parts[DUK_DATE_IDX_YEAR] > 2037)) {
/* be paranoid for 32-bit time values (even avoiding negative ones) */
return 0;
}
duk_memzero(&tm, sizeof(tm));
tm.tm_sec = parts[DUK_DATE_IDX_SECOND];
tm.tm_min = parts[DUK_DATE_IDX_MINUTE];
tm.tm_hour = parts[DUK_DATE_IDX_HOUR];
tm.tm_mday = parts[DUK_DATE_IDX_DAY]; /* already one-based */
tm.tm_mon = parts[DUK_DATE_IDX_MONTH] - 1; /* one-based -> zero-based */
tm.tm_year = parts[DUK_DATE_IDX_YEAR] - 1900;
tm.tm_wday = parts[DUK_DATE_IDX_WEEKDAY];
tm.tm_isdst = 0;
duk_memzero(buf, sizeof(buf));
if ((flags & DUK_DATE_FLAG_TOSTRING_DATE) && (flags & DUK_DATE_FLAG_TOSTRING_TIME)) {
fmt = "%c";
} else if (flags & DUK_DATE_FLAG_TOSTRING_DATE) {
fmt = "%x";
} else {
DUK_ASSERT(flags & DUK_DATE_FLAG_TOSTRING_TIME);
fmt = "%X";
}
(void) strftime(buf, sizeof(buf) - 1, fmt, &tm);
DUK_ASSERT(buf[sizeof(buf) - 1] == 0);
duk_push_string(thr, buf);
return 1;
}
#endif /* DUK_USE_DATE_FMT_STRFTIME */
#if defined(DUK_USE_GET_MONOTONIC_TIME_CLOCK_GETTIME)
DUK_INTERNAL duk_double_t duk_bi_date_get_monotonic_time_clock_gettime(void) {
struct timespec ts;
if (clock_gettime(CLOCK_MONOTONIC, &ts) == 0) {
return (duk_double_t) ts.tv_sec * 1000.0 + (duk_double_t) ts.tv_nsec / 1000000.0;
} else {
DUK_D(DUK_DPRINT("clock_gettime(CLOCK_MONOTONIC) failed"));
return 0.0;
}
}
#endif