| yuezonghe | 824eb0c | 2024-06-27 02:32:26 -0700 | [diff] [blame] | 1 | /* Copyright (C) 2003, 2004, 2007, 2008 Free Software Foundation, Inc. |
| 2 | This file is part of the GNU C Library. |
| 3 | Contributed by Ulrich Drepper <drepper@redhat.com>, 2003. |
| 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, write to the Free |
| 17 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 18 | 02111-1307 USA. */ |
| 19 | |
| 20 | #include <assert.h> |
| 21 | #include <errno.h> |
| 22 | #include <stdbool.h> |
| 23 | #include <time.h> |
| 24 | #include <sysdep.h> |
| 25 | #include "pthreadP.h" |
| 26 | #include <bits/kernel-features.h> |
| 27 | |
| 28 | |
| 29 | int |
| 30 | pthread_condattr_setclock ( |
| 31 | pthread_condattr_t *attr, |
| 32 | clockid_t clock_id) |
| 33 | { |
| 34 | /* Only a few clocks are allowed. CLOCK_REALTIME is always allowed. |
| 35 | CLOCK_MONOTONIC only if the kernel has the necessary support. */ |
| 36 | if (clock_id == CLOCK_MONOTONIC) |
| 37 | { |
| 38 | #ifndef __ASSUME_POSIX_TIMERS |
| 39 | # ifdef __NR_clock_getres |
| 40 | /* Check whether the clock is available. */ |
| 41 | static int avail; |
| 42 | |
| 43 | if (avail == 0) |
| 44 | { |
| 45 | struct timespec ts; |
| 46 | |
| 47 | INTERNAL_SYSCALL_DECL (err); |
| 48 | int val; |
| 49 | val = INTERNAL_SYSCALL (clock_getres, err, 2, CLOCK_MONOTONIC, &ts); |
| 50 | avail = INTERNAL_SYSCALL_ERROR_P (val, err) ? -1 : 1; |
| 51 | } |
| 52 | |
| 53 | if (avail < 0) |
| 54 | # endif |
| 55 | /* Not available. */ |
| 56 | return EINVAL; |
| 57 | #endif |
| 58 | } |
| 59 | else if (clock_id != CLOCK_REALTIME) |
| 60 | /* If more clocks are allowed some day the storing of the clock ID |
| 61 | in the pthread_cond_t structure needs to be adjusted. */ |
| 62 | return EINVAL; |
| 63 | |
| 64 | /* Make sure the value fits in the bits we reserved. */ |
| 65 | assert (clock_id < (1 << COND_NWAITERS_SHIFT)); |
| 66 | |
| 67 | int *valuep = &((struct pthread_condattr *) attr)->value; |
| 68 | |
| 69 | *valuep = ((*valuep & ~(((1 << COND_NWAITERS_SHIFT) - 1) << 1)) |
| 70 | | (clock_id << 1)); |
| 71 | |
| 72 | return 0; |
| 73 | } |