1 #include "Python.h" 2 #ifdef MS_WINDOWS 3 #include <windows.h> 4 #endif 5 6 #if defined(__APPLE__) 7 #include <mach/mach_time.h> /* mach_absolute_time(), mach_timebase_info() */ 8 #endif 9 10 #define _PyTime_check_mul_overflow(a, b) \ 11 (assert(b > 0), \ 12 (_PyTime_t)(a) < _PyTime_MIN / (_PyTime_t)(b) \ 13 || _PyTime_MAX / (_PyTime_t)(b) < (_PyTime_t)(a)) 14 15 /* To millisecond (10^-3) */ 16 #define SEC_TO_MS 1000 17 18 /* To microseconds (10^-6) */ 19 #define MS_TO_US 1000 20 #define SEC_TO_US (SEC_TO_MS * MS_TO_US) 21 22 /* To nanoseconds (10^-9) */ 23 #define US_TO_NS 1000 24 #define MS_TO_NS (MS_TO_US * US_TO_NS) 25 #define SEC_TO_NS (SEC_TO_MS * MS_TO_NS) 26 27 /* Conversion from nanoseconds */ 28 #define NS_TO_MS (1000 * 1000) 29 #define NS_TO_US (1000) 30 31 static void 32 error_time_t_overflow(void) 33 { 34 PyErr_SetString(PyExc_OverflowError, 35 "timestamp out of range for platform time_t"); 36 } 37 38 static void 39 _PyTime_overflow(void) 40 { 41 PyErr_SetString(PyExc_OverflowError, 42 "timestamp too large to convert to C _PyTime_t"); 43 } 44 45 46 _PyTime_t 47 _PyTime_MulDiv(_PyTime_t ticks, _PyTime_t mul, _PyTime_t div) 48 { 49 _PyTime_t intpart, remaining; 50 /* Compute (ticks * mul / div) in two parts to prevent integer overflow: 51 compute integer part, and then the remaining part. 52 53 (ticks * mul) / div == (ticks / div) * mul + (ticks % div) * mul / div 54 55 The caller must ensure that "(div - 1) * mul" cannot overflow. */ 56 intpart = ticks / div; 57 ticks %= div; 58 remaining = ticks * mul; 59 remaining /= div; 60 return intpart * mul + remaining; 61 } 62 63 64 time_t 65 _PyLong_AsTime_t(PyObject *obj) 66 { 67 #if SIZEOF_TIME_T == SIZEOF_LONG_LONG 68 long long val; 69 val = PyLong_AsLongLong(obj); 70 #else 71 long val; 72 Py_BUILD_ASSERT(sizeof(time_t) <= sizeof(long)); 73 val = PyLong_AsLong(obj); 74 #endif 75 if (val == -1 && PyErr_Occurred()) { 76 if (PyErr_ExceptionMatches(PyExc_OverflowError)) { 77 error_time_t_overflow(); 78 } 79 return -1; 80 } 81 return (time_t)val; 82 } 83 84 PyObject * 85 _PyLong_FromTime_t(time_t t) 86 { 87 #if SIZEOF_TIME_T == SIZEOF_LONG_LONG 88 return PyLong_FromLongLong((long long)t); 89 #else 90 Py_BUILD_ASSERT(sizeof(time_t) <= sizeof(long)); 91 return PyLong_FromLong((long)t); 92 #endif 93 } 94 95 /* Round to nearest with ties going to nearest even integer 96 (_PyTime_ROUND_HALF_EVEN) */ 97 static double 98 _PyTime_RoundHalfEven(double x) 99 { 100 double rounded = round(x); 101 if (fabs(x-rounded) == 0.5) { 102 /* halfway case: round to even */ 103 rounded = 2.0*round(x/2.0); 104 } 105 return rounded; 106 } 107 108 static double 109 _PyTime_Round(double x, _PyTime_round_t round) 110 { 111 /* volatile avoids optimization changing how numbers are rounded */ 112 volatile double d; 113 114 d = x; 115 if (round == _PyTime_ROUND_HALF_EVEN) { 116 d = _PyTime_RoundHalfEven(d); 117 } 118 else if (round == _PyTime_ROUND_CEILING) { 119 d = ceil(d); 120 } 121 else if (round == _PyTime_ROUND_FLOOR) { 122 d = floor(d); 123 } 124 else { 125 assert(round == _PyTime_ROUND_UP); 126 d = (d >= 0.0) ? ceil(d) : floor(d); 127 } 128 return d; 129 } 130 131 static int 132 _PyTime_DoubleToDenominator(double d, time_t *sec, long *numerator, 133 long idenominator, _PyTime_round_t round) 134 { 135 double denominator = (double)idenominator; 136 double intpart; 137 /* volatile avoids optimization changing how numbers are rounded */ 138 volatile double floatpart; 139 140 floatpart = modf(d, &intpart); 141 142 floatpart *= denominator; 143 floatpart = _PyTime_Round(floatpart, round); 144 if (floatpart >= denominator) { 145 floatpart -= denominator; 146 intpart += 1.0; 147 } 148 else if (floatpart < 0) { 149 floatpart += denominator; 150 intpart -= 1.0; 151 } 152 assert(0.0 <= floatpart && floatpart < denominator); 153 154 if (!_Py_InIntegralTypeRange(time_t, intpart)) { 155 error_time_t_overflow(); 156 return -1; 157 } 158 *sec = (time_t)intpart; 159 *numerator = (long)floatpart; 160 assert(0 <= *numerator && *numerator < idenominator); 161 return 0; 162 } 163 164 static int 165 _PyTime_ObjectToDenominator(PyObject *obj, time_t *sec, long *numerator, 166 long denominator, _PyTime_round_t round) 167 { 168 assert(denominator >= 1); 169 170 if (PyFloat_Check(obj)) { 171 double d = PyFloat_AsDouble(obj); 172 if (Py_IS_NAN(d)) { 173 *numerator = 0; 174 PyErr_SetString(PyExc_ValueError, "Invalid value NaN (not a number)"); 175 return -1; 176 } 177 return _PyTime_DoubleToDenominator(d, sec, numerator, 178 denominator, round); 179 } 180 else { 181 *sec = _PyLong_AsTime_t(obj); 182 *numerator = 0; 183 if (*sec == (time_t)-1 && PyErr_Occurred()) { 184 return -1; 185 } 186 return 0; 187 } 188 } 189 190 int 191 _PyTime_ObjectToTime_t(PyObject *obj, time_t *sec, _PyTime_round_t round) 192 { 193 if (PyFloat_Check(obj)) { 194 double intpart; 195 /* volatile avoids optimization changing how numbers are rounded */ 196 volatile double d; 197 198 d = PyFloat_AsDouble(obj); 199 if (Py_IS_NAN(d)) { 200 PyErr_SetString(PyExc_ValueError, "Invalid value NaN (not a number)"); 201 return -1; 202 } 203 204 d = _PyTime_Round(d, round); 205 (void)modf(d, &intpart); 206 207 if (!_Py_InIntegralTypeRange(time_t, intpart)) { 208 error_time_t_overflow(); 209 return -1; 210 } 211 *sec = (time_t)intpart; 212 return 0; 213 } 214 else { 215 *sec = _PyLong_AsTime_t(obj); 216 if (*sec == (time_t)-1 && PyErr_Occurred()) { 217 return -1; 218 } 219 return 0; 220 } 221 } 222 223 int 224 _PyTime_ObjectToTimespec(PyObject *obj, time_t *sec, long *nsec, 225 _PyTime_round_t round) 226 { 227 return _PyTime_ObjectToDenominator(obj, sec, nsec, SEC_TO_NS, round); 228 } 229 230 int 231 _PyTime_ObjectToTimeval(PyObject *obj, time_t *sec, long *usec, 232 _PyTime_round_t round) 233 { 234 return _PyTime_ObjectToDenominator(obj, sec, usec, SEC_TO_US, round); 235 } 236 237 _PyTime_t 238 _PyTime_FromSeconds(int seconds) 239 { 240 _PyTime_t t; 241 /* ensure that integer overflow cannot happen, int type should have 32 242 bits, whereas _PyTime_t type has at least 64 bits (SEC_TO_MS takes 30 243 bits). */ 244 Py_BUILD_ASSERT(INT_MAX <= _PyTime_MAX / SEC_TO_NS); 245 Py_BUILD_ASSERT(INT_MIN >= _PyTime_MIN / SEC_TO_NS); 246 247 t = (_PyTime_t)seconds; 248 assert((t >= 0 && t <= _PyTime_MAX / SEC_TO_NS) 249 || (t < 0 && t >= _PyTime_MIN / SEC_TO_NS)); 250 t *= SEC_TO_NS; 251 return t; 252 } 253 254 _PyTime_t 255 _PyTime_FromNanoseconds(_PyTime_t ns) 256 { 257 /* _PyTime_t already uses nanosecond resolution, no conversion needed */ 258 return ns; 259 } 260 261 int 262 _PyTime_FromNanosecondsObject(_PyTime_t *tp, PyObject *obj) 263 { 264 long long nsec; 265 _PyTime_t t; 266 267 if (!PyLong_Check(obj)) { 268 PyErr_Format(PyExc_TypeError, "expect int, got %s", 269 Py_TYPE(obj)->tp_name); 270 return -1; 271 } 272 273 Py_BUILD_ASSERT(sizeof(long long) == sizeof(_PyTime_t)); 274 nsec = PyLong_AsLongLong(obj); 275 if (nsec == -1 && PyErr_Occurred()) { 276 if (PyErr_ExceptionMatches(PyExc_OverflowError)) { 277 _PyTime_overflow(); 278 } 279 return -1; 280 } 281 282 /* _PyTime_t already uses nanosecond resolution, no conversion needed */ 283 t = (_PyTime_t)nsec; 284 *tp = t; 285 return 0; 286 } 287 288 #ifdef HAVE_CLOCK_GETTIME 289 static int 290 pytime_fromtimespec(_PyTime_t *tp, struct timespec *ts, int raise) 291 { 292 _PyTime_t t, nsec; 293 int res = 0; 294 295 Py_BUILD_ASSERT(sizeof(ts->tv_sec) <= sizeof(_PyTime_t)); 296 t = (_PyTime_t)ts->tv_sec; 297 298 if (_PyTime_check_mul_overflow(t, SEC_TO_NS)) { 299 if (raise) { 300 _PyTime_overflow(); 301 } 302 res = -1; 303 t = (t > 0) ? _PyTime_MAX : _PyTime_MIN; 304 } 305 else { 306 t = t * SEC_TO_NS; 307 } 308 309 nsec = ts->tv_nsec; 310 /* The following test is written for positive only nsec */ 311 assert(nsec >= 0); 312 if (t > _PyTime_MAX - nsec) { 313 if (raise) { 314 _PyTime_overflow(); 315 } 316 res = -1; 317 t = _PyTime_MAX; 318 } 319 else { 320 t += nsec; 321 } 322 323 *tp = t; 324 return res; 325 } 326 327 int 328 _PyTime_FromTimespec(_PyTime_t *tp, struct timespec *ts) 329 { 330 return pytime_fromtimespec(tp, ts, 1); 331 } 332 #endif 333 334 #if !defined(MS_WINDOWS) 335 static int 336 pytime_fromtimeval(_PyTime_t *tp, struct timeval *tv, int raise) 337 { 338 _PyTime_t t, usec; 339 int res = 0; 340 341 Py_BUILD_ASSERT(sizeof(tv->tv_sec) <= sizeof(_PyTime_t)); 342 t = (_PyTime_t)tv->tv_sec; 343 344 if (_PyTime_check_mul_overflow(t, SEC_TO_NS)) { 345 if (raise) { 346 _PyTime_overflow(); 347 } 348 res = -1; 349 t = (t > 0) ? _PyTime_MAX : _PyTime_MIN; 350 } 351 else { 352 t = t * SEC_TO_NS; 353 } 354 355 usec = (_PyTime_t)tv->tv_usec * US_TO_NS; 356 /* The following test is written for positive only usec */ 357 assert(usec >= 0); 358 if (t > _PyTime_MAX - usec) { 359 if (raise) { 360 _PyTime_overflow(); 361 } 362 res = -1; 363 t = _PyTime_MAX; 364 } 365 else { 366 t += usec; 367 } 368 369 *tp = t; 370 return res; 371 } 372 373 int 374 _PyTime_FromTimeval(_PyTime_t *tp, struct timeval *tv) 375 { 376 return pytime_fromtimeval(tp, tv, 1); 377 } 378 #endif 379 380 static int 381 _PyTime_FromDouble(_PyTime_t *t, double value, _PyTime_round_t round, 382 long unit_to_ns) 383 { 384 /* volatile avoids optimization changing how numbers are rounded */ 385 volatile double d; 386 387 /* convert to a number of nanoseconds */ 388 d = value; 389 d *= (double)unit_to_ns; 390 d = _PyTime_Round(d, round); 391 392 if (!_Py_InIntegralTypeRange(_PyTime_t, d)) { 393 _PyTime_overflow(); 394 return -1; 395 } 396 *t = (_PyTime_t)d; 397 return 0; 398 } 399 400 static int 401 _PyTime_FromObject(_PyTime_t *t, PyObject *obj, _PyTime_round_t round, 402 long unit_to_ns) 403 { 404 if (PyFloat_Check(obj)) { 405 double d; 406 d = PyFloat_AsDouble(obj); 407 if (Py_IS_NAN(d)) { 408 PyErr_SetString(PyExc_ValueError, "Invalid value NaN (not a number)"); 409 return -1; 410 } 411 return _PyTime_FromDouble(t, d, round, unit_to_ns); 412 } 413 else { 414 long long sec; 415 Py_BUILD_ASSERT(sizeof(long long) <= sizeof(_PyTime_t)); 416 417 sec = PyLong_AsLongLong(obj); 418 if (sec == -1 && PyErr_Occurred()) { 419 if (PyErr_ExceptionMatches(PyExc_OverflowError)) { 420 _PyTime_overflow(); 421 } 422 return -1; 423 } 424 425 if (_PyTime_check_mul_overflow(sec, unit_to_ns)) { 426 _PyTime_overflow(); 427 return -1; 428 } 429 *t = sec * unit_to_ns; 430 return 0; 431 } 432 } 433 434 int 435 _PyTime_FromSecondsObject(_PyTime_t *t, PyObject *obj, _PyTime_round_t round) 436 { 437 return _PyTime_FromObject(t, obj, round, SEC_TO_NS); 438 } 439 440 int 441 _PyTime_FromMillisecondsObject(_PyTime_t *t, PyObject *obj, _PyTime_round_t round) 442 { 443 return _PyTime_FromObject(t, obj, round, MS_TO_NS); 444 } 445 446 double 447 _PyTime_AsSecondsDouble(_PyTime_t t) 448 { 449 /* volatile avoids optimization changing how numbers are rounded */ 450 volatile double d; 451 452 if (t % SEC_TO_NS == 0) { 453 _PyTime_t secs; 454 /* Divide using integers to avoid rounding issues on the integer part. 455 1e-9 cannot be stored exactly in IEEE 64-bit. */ 456 secs = t / SEC_TO_NS; 457 d = (double)secs; 458 } 459 else { 460 d = (double)t; 461 d /= 1e9; 462 } 463 return d; 464 } 465 466 PyObject * 467 _PyTime_AsNanosecondsObject(_PyTime_t t) 468 { 469 Py_BUILD_ASSERT(sizeof(long long) >= sizeof(_PyTime_t)); 470 return PyLong_FromLongLong((long long)t); 471 } 472 473 static _PyTime_t 474 _PyTime_Divide(const _PyTime_t t, const _PyTime_t k, 475 const _PyTime_round_t round) 476 { 477 assert(k > 1); 478 if (round == _PyTime_ROUND_HALF_EVEN) { 479 _PyTime_t x, r, abs_r; 480 x = t / k; 481 r = t % k; 482 abs_r = Py_ABS(r); 483 if (abs_r > k / 2 || (abs_r == k / 2 && (Py_ABS(x) & 1))) { 484 if (t >= 0) { 485 x++; 486 } 487 else { 488 x--; 489 } 490 } 491 return x; 492 } 493 else if (round == _PyTime_ROUND_CEILING) { 494 if (t >= 0) { 495 return (t + k - 1) / k; 496 } 497 else { 498 return t / k; 499 } 500 } 501 else if (round == _PyTime_ROUND_FLOOR){ 502 if (t >= 0) { 503 return t / k; 504 } 505 else { 506 return (t - (k - 1)) / k; 507 } 508 } 509 else { 510 assert(round == _PyTime_ROUND_UP); 511 if (t >= 0) { 512 return (t + k - 1) / k; 513 } 514 else { 515 return (t - (k - 1)) / k; 516 } 517 } 518 } 519 520 _PyTime_t 521 _PyTime_AsMilliseconds(_PyTime_t t, _PyTime_round_t round) 522 { 523 return _PyTime_Divide(t, NS_TO_MS, round); 524 } 525 526 _PyTime_t 527 _PyTime_AsMicroseconds(_PyTime_t t, _PyTime_round_t round) 528 { 529 return _PyTime_Divide(t, NS_TO_US, round); 530 } 531 532 static int 533 _PyTime_AsTimeval_impl(_PyTime_t t, _PyTime_t *p_secs, int *p_us, 534 _PyTime_round_t round) 535 { 536 _PyTime_t secs, ns; 537 int usec; 538 int res = 0; 539 540 secs = t / SEC_TO_NS; 541 ns = t % SEC_TO_NS; 542 543 usec = (int)_PyTime_Divide(ns, US_TO_NS, round); 544 if (usec < 0) { 545 usec += SEC_TO_US; 546 if (secs != _PyTime_MIN) { 547 secs -= 1; 548 } 549 else { 550 res = -1; 551 } 552 } 553 else if (usec >= SEC_TO_US) { 554 usec -= SEC_TO_US; 555 if (secs != _PyTime_MAX) { 556 secs += 1; 557 } 558 else { 559 res = -1; 560 } 561 } 562 assert(0 <= usec && usec < SEC_TO_US); 563 564 *p_secs = secs; 565 *p_us = usec; 566 567 return res; 568 } 569 570 static int 571 _PyTime_AsTimevalStruct_impl(_PyTime_t t, struct timeval *tv, 572 _PyTime_round_t round, int raise) 573 { 574 _PyTime_t secs, secs2; 575 int us; 576 int res; 577 578 res = _PyTime_AsTimeval_impl(t, &secs, &us, round); 579 580 #ifdef MS_WINDOWS 581 tv->tv_sec = (long)secs; 582 #else 583 tv->tv_sec = secs; 584 #endif 585 tv->tv_usec = us; 586 587 secs2 = (_PyTime_t)tv->tv_sec; 588 if (res < 0 || secs2 != secs) { 589 if (raise) { 590 error_time_t_overflow(); 591 } 592 return -1; 593 } 594 return 0; 595 } 596 597 int 598 _PyTime_AsTimeval(_PyTime_t t, struct timeval *tv, _PyTime_round_t round) 599 { 600 return _PyTime_AsTimevalStruct_impl(t, tv, round, 1); 601 } 602 603 int 604 _PyTime_AsTimeval_noraise(_PyTime_t t, struct timeval *tv, _PyTime_round_t round) 605 { 606 return _PyTime_AsTimevalStruct_impl(t, tv, round, 0); 607 } 608 609 int 610 _PyTime_AsTimevalTime_t(_PyTime_t t, time_t *p_secs, int *us, 611 _PyTime_round_t round) 612 { 613 _PyTime_t secs; 614 int res; 615 616 res = _PyTime_AsTimeval_impl(t, &secs, us, round); 617 618 *p_secs = secs; 619 620 if (res < 0 || (_PyTime_t)*p_secs != secs) { 621 error_time_t_overflow(); 622 return -1; 623 } 624 return 0; 625 } 626 627 628 #if defined(HAVE_CLOCK_GETTIME) || defined(HAVE_KQUEUE) 629 int 630 _PyTime_AsTimespec(_PyTime_t t, struct timespec *ts) 631 { 632 _PyTime_t secs, nsec; 633 634 secs = t / SEC_TO_NS; 635 nsec = t % SEC_TO_NS; 636 if (nsec < 0) { 637 nsec += SEC_TO_NS; 638 secs -= 1; 639 } 640 ts->tv_sec = (time_t)secs; 641 assert(0 <= nsec && nsec < SEC_TO_NS); 642 ts->tv_nsec = nsec; 643 644 if ((_PyTime_t)ts->tv_sec != secs) { 645 error_time_t_overflow(); 646 return -1; 647 } 648 return 0; 649 } 650 #endif 651 652 static int 653 pygettimeofday(_PyTime_t *tp, _Py_clock_info_t *info, int raise) 654 { 655 #ifdef MS_WINDOWS 656 FILETIME system_time; 657 ULARGE_INTEGER large; 658 659 assert(info == NULL || raise); 660 661 GetSystemTimeAsFileTime(&system_time); 662 large.u.LowPart = system_time.dwLowDateTime; 663 large.u.HighPart = system_time.dwHighDateTime; 664 /* 11,644,473,600,000,000,000: number of nanoseconds between 665 the 1st january 1601 and the 1st january 1970 (369 years + 89 leap 666 days). */ 667 *tp = large.QuadPart * 100 - 11644473600000000000; 668 if (info) { 669 DWORD timeAdjustment, timeIncrement; 670 BOOL isTimeAdjustmentDisabled, ok; 671 672 info->implementation = "GetSystemTimeAsFileTime()"; 673 info->monotonic = 0; 674 ok = GetSystemTimeAdjustment(&timeAdjustment, &timeIncrement, 675 &isTimeAdjustmentDisabled); 676 if (!ok) { 677 PyErr_SetFromWindowsErr(0); 678 return -1; 679 } 680 info->resolution = timeIncrement * 1e-7; 681 info->adjustable = 1; 682 } 683 684 #else /* MS_WINDOWS */ 685 int err; 686 #ifdef HAVE_CLOCK_GETTIME 687 struct timespec ts; 688 #else 689 struct timeval tv; 690 #endif 691 692 assert(info == NULL || raise); 693 694 #ifdef HAVE_CLOCK_GETTIME 695 err = clock_gettime(CLOCK_REALTIME, &ts); 696 if (err) { 697 if (raise) { 698 PyErr_SetFromErrno(PyExc_OSError); 699 } 700 return -1; 701 } 702 if (pytime_fromtimespec(tp, &ts, raise) < 0) { 703 return -1; 704 } 705 706 if (info) { 707 struct timespec res; 708 info->implementation = "clock_gettime(CLOCK_REALTIME)"; 709 info->monotonic = 0; 710 info->adjustable = 1; 711 if (clock_getres(CLOCK_REALTIME, &res) == 0) { 712 info->resolution = res.tv_sec + res.tv_nsec * 1e-9; 713 } 714 else { 715 info->resolution = 1e-9; 716 } 717 } 718 #else /* HAVE_CLOCK_GETTIME */ 719 720 /* test gettimeofday() */ 721 #ifdef GETTIMEOFDAY_NO_TZ 722 err = gettimeofday(&tv); 723 #else 724 err = gettimeofday(&tv, (struct timezone *)NULL); 725 #endif 726 if (err) { 727 if (raise) { 728 PyErr_SetFromErrno(PyExc_OSError); 729 } 730 return -1; 731 } 732 if (pytime_fromtimeval(tp, &tv, raise) < 0) { 733 return -1; 734 } 735 736 if (info) { 737 info->implementation = "gettimeofday()"; 738 info->resolution = 1e-6; 739 info->monotonic = 0; 740 info->adjustable = 1; 741 } 742 #endif /* !HAVE_CLOCK_GETTIME */ 743 #endif /* !MS_WINDOWS */ 744 return 0; 745 } 746 747 _PyTime_t 748 _PyTime_GetSystemClock(void) 749 { 750 _PyTime_t t; 751 if (pygettimeofday(&t, NULL, 0) < 0) { 752 /* should not happen, _PyTime_Init() checked the clock at startup */ 753 Py_UNREACHABLE(); 754 } 755 return t; 756 } 757 758 int 759 _PyTime_GetSystemClockWithInfo(_PyTime_t *t, _Py_clock_info_t *info) 760 { 761 return pygettimeofday(t, info, 1); 762 } 763 764 static int 765 pymonotonic(_PyTime_t *tp, _Py_clock_info_t *info, int raise) 766 { 767 #if defined(MS_WINDOWS) 768 ULONGLONG ticks; 769 _PyTime_t t; 770 771 assert(info == NULL || raise); 772 773 ticks = GetTickCount64(); 774 Py_BUILD_ASSERT(sizeof(ticks) <= sizeof(_PyTime_t)); 775 t = (_PyTime_t)ticks; 776 777 if (_PyTime_check_mul_overflow(t, MS_TO_NS)) { 778 if (raise) { 779 _PyTime_overflow(); 780 return -1; 781 } 782 /* Hello, time traveler! */ 783 Py_UNREACHABLE(); 784 } 785 *tp = t * MS_TO_NS; 786 787 if (info) { 788 DWORD timeAdjustment, timeIncrement; 789 BOOL isTimeAdjustmentDisabled, ok; 790 info->implementation = "GetTickCount64()"; 791 info->monotonic = 1; 792 ok = GetSystemTimeAdjustment(&timeAdjustment, &timeIncrement, 793 &isTimeAdjustmentDisabled); 794 if (!ok) { 795 PyErr_SetFromWindowsErr(0); 796 return -1; 797 } 798 info->resolution = timeIncrement * 1e-7; 799 info->adjustable = 0; 800 } 801 802 #elif defined(__APPLE__) 803 static mach_timebase_info_data_t timebase; 804 static uint64_t t0 = 0; 805 uint64_t ticks; 806 807 if (timebase.denom == 0) { 808 /* According to the Technical Q&A QA1398, mach_timebase_info() cannot 809 fail: https://developer.apple.com/library/mac/#qa/qa1398/ */ 810 (void)mach_timebase_info(&timebase); 811 812 /* Sanity check: should never occur in practice */ 813 if (timebase.numer < 1 || timebase.denom < 1) { 814 PyErr_SetString(PyExc_RuntimeError, 815 "invalid mach_timebase_info"); 816 return -1; 817 } 818 819 /* Check that timebase.numer and timebase.denom can be casted to 820 _PyTime_t. In practice, timebase uses uint32_t, so casting cannot 821 overflow. At the end, only make sure that the type is uint32_t 822 (_PyTime_t is 64-bit long). */ 823 assert(sizeof(timebase.numer) < sizeof(_PyTime_t)); 824 assert(sizeof(timebase.denom) < sizeof(_PyTime_t)); 825 826 /* Make sure that (ticks * timebase.numer) cannot overflow in 827 _PyTime_MulDiv(), with ticks < timebase.denom. 828 829 Known time bases: 830 831 * always (1, 1) on Intel 832 * (1000000000, 33333335) or (1000000000, 25000000) on PowerPC 833 834 None of these time bases can overflow with 64-bit _PyTime_t, but 835 check for overflow, just in case. */ 836 if ((_PyTime_t)timebase.numer > _PyTime_MAX / (_PyTime_t)timebase.denom) { 837 PyErr_SetString(PyExc_OverflowError, 838 "mach_timebase_info is too large"); 839 return -1; 840 } 841 842 t0 = mach_absolute_time(); 843 } 844 845 if (info) { 846 info->implementation = "mach_absolute_time()"; 847 info->resolution = (double)timebase.numer / (double)timebase.denom * 1e-9; 848 info->monotonic = 1; 849 info->adjustable = 0; 850 } 851 852 ticks = mach_absolute_time(); 853 /* Use a "time zero" to reduce precision loss when converting time 854 to floatting point number, as in time.monotonic(). */ 855 ticks -= t0; 856 *tp = _PyTime_MulDiv(ticks, 857 (_PyTime_t)timebase.numer, 858 (_PyTime_t)timebase.denom); 859 860 #elif defined(__hpux) 861 hrtime_t time; 862 863 time = gethrtime(); 864 if (time == -1) { 865 if (raise) { 866 PyErr_SetFromErrno(PyExc_OSError); 867 } 868 return -1; 869 } 870 871 *tp = time; 872 873 if (info) { 874 info->implementation = "gethrtime()"; 875 info->resolution = 1e-9; 876 info->monotonic = 1; 877 info->adjustable = 0; 878 } 879 880 #else 881 struct timespec ts; 882 #ifdef CLOCK_HIGHRES 883 const clockid_t clk_id = CLOCK_HIGHRES; 884 const char *implementation = "clock_gettime(CLOCK_HIGHRES)"; 885 #else 886 const clockid_t clk_id = CLOCK_MONOTONIC; 887 const char *implementation = "clock_gettime(CLOCK_MONOTONIC)"; 888 #endif 889 890 assert(info == NULL || raise); 891 892 if (clock_gettime(clk_id, &ts) != 0) { 893 if (raise) { 894 PyErr_SetFromErrno(PyExc_OSError); 895 return -1; 896 } 897 return -1; 898 } 899 900 if (info) { 901 struct timespec res; 902 info->monotonic = 1; 903 info->implementation = implementation; 904 info->adjustable = 0; 905 if (clock_getres(clk_id, &res) != 0) { 906 PyErr_SetFromErrno(PyExc_OSError); 907 return -1; 908 } 909 info->resolution = res.tv_sec + res.tv_nsec * 1e-9; 910 } 911 if (pytime_fromtimespec(tp, &ts, raise) < 0) { 912 return -1; 913 } 914 #endif 915 return 0; 916 } 917 918 _PyTime_t 919 _PyTime_GetMonotonicClock(void) 920 { 921 _PyTime_t t; 922 if (pymonotonic(&t, NULL, 0) < 0) { 923 /* should not happen, _PyTime_Init() checked that monotonic clock at 924 startup */ 925 Py_UNREACHABLE(); 926 } 927 return t; 928 } 929 930 int 931 _PyTime_GetMonotonicClockWithInfo(_PyTime_t *tp, _Py_clock_info_t *info) 932 { 933 return pymonotonic(tp, info, 1); 934 } 935 936 937 #ifdef MS_WINDOWS 938 static int 939 win_perf_counter(_PyTime_t *tp, _Py_clock_info_t *info) 940 { 941 static LONGLONG frequency = 0; 942 static LONGLONG t0 = 0; 943 LARGE_INTEGER now; 944 LONGLONG ticksll; 945 _PyTime_t ticks; 946 947 if (frequency == 0) { 948 LARGE_INTEGER freq; 949 if (!QueryPerformanceFrequency(&freq)) { 950 PyErr_SetFromWindowsErr(0); 951 return -1; 952 } 953 frequency = freq.QuadPart; 954 955 /* Sanity check: should never occur in practice */ 956 if (frequency < 1) { 957 PyErr_SetString(PyExc_RuntimeError, 958 "invalid QueryPerformanceFrequency"); 959 return -1; 960 } 961 962 /* Check that frequency can be casted to _PyTime_t. 963 964 Make also sure that (ticks * SEC_TO_NS) cannot overflow in 965 _PyTime_MulDiv(), with ticks < frequency. 966 967 Known QueryPerformanceFrequency() values: 968 969 * 10,000,000 (10 MHz): 100 ns resolution 970 * 3,579,545 Hz (3.6 MHz): 279 ns resolution 971 972 None of these frequencies can overflow with 64-bit _PyTime_t, but 973 check for overflow, just in case. */ 974 if (frequency > _PyTime_MAX 975 || frequency > (LONGLONG)_PyTime_MAX / (LONGLONG)SEC_TO_NS) { 976 PyErr_SetString(PyExc_OverflowError, 977 "QueryPerformanceFrequency is too large"); 978 return -1; 979 } 980 981 QueryPerformanceCounter(&now); 982 t0 = now.QuadPart; 983 } 984 985 if (info) { 986 info->implementation = "QueryPerformanceCounter()"; 987 info->resolution = 1.0 / (double)frequency; 988 info->monotonic = 1; 989 info->adjustable = 0; 990 } 991 992 QueryPerformanceCounter(&now); 993 ticksll = now.QuadPart; 994 995 /* Use a "time zero" to reduce precision loss when converting time 996 to floatting point number, as in time.perf_counter(). */ 997 ticksll -= t0; 998 999 /* Make sure that casting LONGLONG to _PyTime_t cannot overflow, 1000 both types are signed */ 1001 Py_BUILD_ASSERT(sizeof(ticksll) <= sizeof(ticks)); 1002 ticks = (_PyTime_t)ticksll; 1003 1004 *tp = _PyTime_MulDiv(ticks, SEC_TO_NS, (_PyTime_t)frequency); 1005 return 0; 1006 } 1007 #endif 1008 1009 1010 int 1011 _PyTime_GetPerfCounterWithInfo(_PyTime_t *t, _Py_clock_info_t *info) 1012 { 1013 #ifdef MS_WINDOWS 1014 return win_perf_counter(t, info); 1015 #else 1016 return _PyTime_GetMonotonicClockWithInfo(t, info); 1017 #endif 1018 } 1019 1020 1021 _PyTime_t 1022 _PyTime_GetPerfCounter(void) 1023 { 1024 _PyTime_t t; 1025 if (_PyTime_GetPerfCounterWithInfo(&t, NULL)) { 1026 Py_UNREACHABLE(); 1027 } 1028 return t; 1029 } 1030 1031 1032 int 1033 _PyTime_Init(void) 1034 { 1035 /* check that time.time(), time.monotonic() and time.perf_counter() clocks 1036 are working properly to not have to check for exceptions at runtime. If 1037 a clock works once, it cannot fail in next calls. */ 1038 _PyTime_t t; 1039 if (_PyTime_GetSystemClockWithInfo(&t, NULL) < 0) { 1040 return -1; 1041 } 1042 if (_PyTime_GetMonotonicClockWithInfo(&t, NULL) < 0) { 1043 return -1; 1044 } 1045 if (_PyTime_GetPerfCounterWithInfo(&t, NULL) < 0) { 1046 return -1; 1047 } 1048 return 0; 1049 } 1050 1051 int 1052 _PyTime_localtime(time_t t, struct tm *tm) 1053 { 1054 #ifdef MS_WINDOWS 1055 int error; 1056 1057 error = localtime_s(tm, &t); 1058 if (error != 0) { 1059 errno = error; 1060 PyErr_SetFromErrno(PyExc_OSError); 1061 return -1; 1062 } 1063 return 0; 1064 #else /* !MS_WINDOWS */ 1065 if (localtime_r(&t, tm) == NULL) { 1066 #ifdef EINVAL 1067 if (errno == 0) { 1068 errno = EINVAL; 1069 } 1070 #endif 1071 PyErr_SetFromErrno(PyExc_OSError); 1072 return -1; 1073 } 1074 return 0; 1075 #endif /* MS_WINDOWS */ 1076 } 1077 1078 int 1079 _PyTime_gmtime(time_t t, struct tm *tm) 1080 { 1081 #ifdef MS_WINDOWS 1082 int error; 1083 1084 error = gmtime_s(tm, &t); 1085 if (error != 0) { 1086 errno = error; 1087 PyErr_SetFromErrno(PyExc_OSError); 1088 return -1; 1089 } 1090 return 0; 1091 #else /* !MS_WINDOWS */ 1092 if (gmtime_r(&t, tm) == NULL) { 1093 #ifdef EINVAL 1094 if (errno == 0) { 1095 errno = EINVAL; 1096 } 1097 #endif 1098 PyErr_SetFromErrno(PyExc_OSError); 1099 return -1; 1100 } 1101 return 0; 1102 #endif /* MS_WINDOWS */ 1103 } 1104
