1 /* pthread_condattr_setclock. Generic version. 2 Copyright (C) 2002-2021 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 <https://www.gnu.org/licenses/>. */ 18 19 #include <pthread.h> 20 #include <pt-internal.h> 21 22 int pthread_condattr_setclock(pthread_condattr_t * attr,clockid_t clock)23pthread_condattr_setclock (pthread_condattr_t *attr, clockid_t clock) 24 { 25 /* Only a few clocks are allowed. CLOCK_REALTIME is always allowed. 26 CLOCK_MONOTONIC only if the kernel has the necessary support. */ 27 if (clock == CLOCK_MONOTONIC) 28 { 29 /* Check whether the clock is available. */ 30 static int avail; 31 32 if (avail == 0) 33 { 34 struct timespec ts; 35 int res; 36 37 res = clock_gettime (CLOCK_MONOTONIC, &ts); 38 avail = res < 0 ? -1 : 1; 39 } 40 41 if (avail < 0) 42 /* Not available. */ 43 return EINVAL; 44 } 45 else if (clock != CLOCK_REALTIME) 46 return EINVAL; 47 48 attr->__clock = clock; 49 50 return 0; 51 } 52