| xf.li | bfc6e71 | 2025-02-07 01:54:34 -0800 | [diff] [blame^] | 1 | /* High-resolution sleep with the specified clock. |
| 2 | Copyright (C) 2000-2016 Free Software Foundation, Inc. |
| 3 | This file is part of the GNU C Library. |
| 4 | |
| 5 | The GNU C Library is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2.1 of the License, or (at your option) any later version. |
| 9 | |
| 10 | The GNU C Library is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with the GNU C Library; if not, see |
| 17 | <http://www.gnu.org/licenses/>. */ |
| 18 | |
| 19 | #include <assert.h> |
| 20 | #include <errno.h> |
| 21 | #include <time.h> |
| 22 | #include <hp-timing.h> |
| 23 | #include <sysdep-cancel.h> |
| 24 | |
| 25 | #if HP_TIMING_AVAIL |
| 26 | # define CPUCLOCK_P(clock) \ |
| 27 | ((clock) == CLOCK_PROCESS_CPUTIME_ID \ |
| 28 | || ((clock) & ((1 << CLOCK_IDFIELD_SIZE) - 1)) == CLOCK_THREAD_CPUTIME_ID) |
| 29 | #else |
| 30 | # define CPUCLOCK_P(clock) 0 |
| 31 | #endif |
| 32 | |
| 33 | #ifndef INVALID_CLOCK_P |
| 34 | # define INVALID_CLOCK_P(cl) \ |
| 35 | ((cl) < CLOCK_REALTIME || (cl) > CLOCK_THREAD_CPUTIME_ID) |
| 36 | #endif |
| 37 | |
| 38 | |
| 39 | /* This implementation assumes that these is only a `nanosleep' system |
| 40 | call. So we have to remap all other activities. */ |
| 41 | int |
| 42 | __clock_nanosleep (clockid_t clock_id, int flags, const struct timespec *req, |
| 43 | struct timespec *rem) |
| 44 | { |
| 45 | struct timespec now; |
| 46 | |
| 47 | if (__builtin_expect (req->tv_nsec, 0) < 0 |
| 48 | || __builtin_expect (req->tv_nsec, 0) >= 1000000000) |
| 49 | return EINVAL; |
| 50 | |
| 51 | if (clock_id == CLOCK_THREAD_CPUTIME_ID) |
| 52 | return EINVAL; /* POSIX specifies EINVAL for this case. */ |
| 53 | |
| 54 | #ifdef SYSDEP_NANOSLEEP |
| 55 | SYSDEP_NANOSLEEP; |
| 56 | #endif |
| 57 | |
| 58 | if (CPUCLOCK_P (clock_id)) |
| 59 | return ENOTSUP; |
| 60 | |
| 61 | if (INVALID_CLOCK_P (clock_id)) |
| 62 | return EINVAL; |
| 63 | |
| 64 | /* If we got an absolute time, remap it. */ |
| 65 | if (flags == TIMER_ABSTIME) |
| 66 | { |
| 67 | long int nsec; |
| 68 | long int sec; |
| 69 | |
| 70 | /* Make sure we use safe data types. */ |
| 71 | assert (sizeof (sec) >= sizeof (now.tv_sec)); |
| 72 | |
| 73 | /* Get the current time for this clock. */ |
| 74 | if (__builtin_expect (clock_gettime (clock_id, &now), 0) != 0) |
| 75 | return errno; |
| 76 | |
| 77 | /* Compute the difference. */ |
| 78 | nsec = req->tv_nsec - now.tv_nsec; |
| 79 | sec = req->tv_sec - now.tv_sec - (nsec < 0); |
| 80 | if (sec < 0) |
| 81 | /* The time has already elapsed. */ |
| 82 | return 0; |
| 83 | |
| 84 | now.tv_sec = sec; |
| 85 | now.tv_nsec = nsec + (nsec < 0 ? 1000000000 : 0); |
| 86 | |
| 87 | /* From now on this is our time. */ |
| 88 | req = &now; |
| 89 | |
| 90 | /* Make sure we are not modifying the struct pointed to by REM. */ |
| 91 | rem = NULL; |
| 92 | } |
| 93 | else if (__builtin_expect (flags, 0) != 0) |
| 94 | return EINVAL; |
| 95 | else if (clock_id != CLOCK_REALTIME) |
| 96 | /* Not supported. */ |
| 97 | return ENOTSUP; |
| 98 | |
| 99 | return __builtin_expect (nanosleep (req, rem), 0) ? errno : 0; |
| 100 | } |
| 101 | weak_alias (__clock_nanosleep, clock_nanosleep) |