semaphore.c revision 1dc9e472e19acfe6dc7f41e429236e7eef7ceda1
11dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project/* 21dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Copyright (C) 2008 The Android Open Source Project 31dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * All rights reserved. 41dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * 51dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * Redistribution and use in source and binary forms, with or without 61dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * modification, are permitted provided that the following conditions 71dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * are met: 81dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * * Redistributions of source code must retain the above copyright 91dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * notice, this list of conditions and the following disclaimer. 101dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * * Redistributions in binary form must reproduce the above copyright 111dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * notice, this list of conditions and the following disclaimer in 121dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * the documentation and/or other materials provided with the 131dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * distribution. 141dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * 151dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 161dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 171dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 181dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 191dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 201dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 211dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 221dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 231dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 241dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 251dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 261dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * SUCH DAMAGE. 271dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project */ 281dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include <semaphore.h> 291dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include <errno.h> 301dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include <sys/time.h> 311dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include <sys/atomics.h> 321dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project#include <time.h> 331dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 341dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectint sem_init(sem_t *sem, int pshared, unsigned int value) 351dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 361dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (sem == NULL) { 371dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = EINVAL; 381dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 391dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 401dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 411dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (pshared != 0) { 421dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = ENOSYS; 431dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 441dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 451dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 461dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project sem->count = value; 471dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return 0; 481dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 491dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 501dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 511dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectint sem_destroy(sem_t *sem) 521dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 531dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (sem == NULL) { 541dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = EINVAL; 551dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 561dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 571dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (sem->count == 0) { 581dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = EBUSY; 591dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 601dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 611dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return 0; 621dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 631dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 641dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 651dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectsem_t *sem_open(const char *name, int oflag, ...) 661dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 671dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project name=name; 681dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project oflag=oflag; 691dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 701dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = ENOSYS; 711dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return SEM_FAILED; 721dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 731dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 741dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 751dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectint sem_close(sem_t *sem) 761dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 771dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (sem == NULL) { 781dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = EINVAL; 791dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 801dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 811dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = ENOSYS; 821dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 831dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 841dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 851dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 861dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectint sem_unlink(const char * name) 871dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 881dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = ENOSYS; 891dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 901dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 911dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 921dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 931dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectstatic int 941dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project__atomic_dec_if_positive( volatile unsigned int* pvalue ) 951dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 961dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project unsigned int old; 971dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 981dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project do { 991dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project old = *pvalue; 1001dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1011dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project while ( old != 0 && __atomic_cmpxchg( (int)old, (int)old-1, (volatile int*)pvalue ) != 0 ); 1021dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1031dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return old; 1041dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 1051dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1061dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectint sem_wait(sem_t *sem) 1071dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 1081dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (sem == NULL) { 1091dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = EINVAL; 1101dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 1111dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1121dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1131dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project for (;;) { 1141dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (__atomic_dec_if_positive(&sem->count)) 1151dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project break; 1161dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1171dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project __futex_wait(&sem->count, 0, 0); 1181dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1191dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return 0; 1201dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 1211dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1221dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectint sem_timedwait(sem_t *sem, const struct timespec *abs_timeout) 1231dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 1241dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project int ret; 1251dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1261dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (sem == NULL) { 1271dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = EINVAL; 1281dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 1291dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1301dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1311dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project /* POSIX says we need to try to decrement the semaphore 1321dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project * before checking the timeout value */ 1331dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (__atomic_dec_if_positive(&sem->count)) 1341dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return 0; 1351dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1361dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project /* check it as per Posix */ 1371dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (abs_timeout == NULL || 1381dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project abs_timeout->tv_sec < 0 || 1391dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project abs_timeout->tv_nsec < 0 || 1401dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project abs_timeout->tv_nsec >= 1000000000) 1411dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project { 1421dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = EINVAL; 1431dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 1441dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1451dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1461dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project for (;;) { 1471dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project struct timespec ts; 1481dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project int ret; 1491dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1501dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project /* Posix mandates CLOCK_REALTIME here */ 1511dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project clock_gettime( CLOCK_REALTIME, &ts ); 1521dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project ts.tv_sec = abs_timeout->tv_sec - ts.tv_sec; 1531dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project ts.tv_nsec = abs_timeout->tv_nsec - ts.tv_nsec; 1541dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (ts.tv_nsec < 0) { 1551dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project ts.tv_nsec += 1000000000; 1561dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project ts.tv_sec -= 1; 1571dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1581dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1591dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (ts.tv_sec < 0 || ts.tv_nsec < 0) { 1601dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = ETIMEDOUT; 1611dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 1621dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1631dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1641dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project ret = __futex_wait(&sem->count, 0, &ts); 1651dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1661dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project /* return in case of timeout or interrupt */ 1671dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (ret == -ETIMEDOUT || ret == -EINTR) { 1681dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = -ret; 1691dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 1701dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1711dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1721dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (__atomic_dec_if_positive(&sem->count)) 1731dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project break; 1741dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1751dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return 0; 1761dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 1771dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1781dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectint sem_post(sem_t *sem) 1791dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 1801dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (sem == NULL) 1811dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return EINVAL; 1821dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1831dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (__atomic_inc((volatile int*)&sem->count) == 0) 1841dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project __futex_wake(&sem->count, 1); 1851dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1861dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return 0; 1871dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 1881dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1891dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectint sem_trywait(sem_t *sem) 1901dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 1911dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (sem == NULL) { 1921dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = EINVAL; 1931dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 1941dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 1951dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 1961dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (__atomic_dec_if_positive(&sem->count) > 0) { 1971dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return 0; 1981dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } else { 1991dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return EAGAIN; 2001dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 2011dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 2021dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 2031dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Projectint sem_getvalue(sem_t *sem, int *sval) 2041dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project{ 2051dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project if (sem == NULL || sval == NULL) { 2061dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project errno = EINVAL; 2071dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return -1; 2081dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project } 2091dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project 2101dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project *sval = sem->count; 2111dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project return 0; 2121dc9e472e19acfe6dc7f41e429236e7eef7ceda1The Android Open Source Project} 213