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-rw-r--r--libc/bionic/semaphore.c212
1 files changed, 0 insertions, 212 deletions
diff --git a/libc/bionic/semaphore.c b/libc/bionic/semaphore.c
deleted file mode 100644
index 0c94600..0000000
--- a/libc/bionic/semaphore.c
+++ /dev/null
@@ -1,212 +0,0 @@
-/*
- * Copyright (C) 2008 The Android Open Source Project
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * * Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
- * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-#include <semaphore.h>
-#include <errno.h>
-#include <sys/time.h>
-#include <sys/atomics.h>
-#include <time.h>
-
-int sem_init(sem_t *sem, int pshared, unsigned int value)
-{
- if (sem == NULL) {
- errno = EINVAL;
- return -1;
- }
-
- if (pshared != 0) {
- errno = ENOSYS;
- return -1;
- }
-
- sem->count = value;
- return 0;
-}
-
-
-int sem_destroy(sem_t *sem)
-{
- if (sem == NULL) {
- errno = EINVAL;
- return -1;
- }
- if (sem->count == 0) {
- errno = EBUSY;
- return -1;
- }
- return 0;
-}
-
-
-sem_t *sem_open(const char *name, int oflag, ...)
-{
- name=name;
- oflag=oflag;
-
- errno = ENOSYS;
- return SEM_FAILED;
-}
-
-
-int sem_close(sem_t *sem)
-{
- if (sem == NULL) {
- errno = EINVAL;
- return -1;
- }
- errno = ENOSYS;
- return -1;
-}
-
-
-int sem_unlink(const char * name)
-{
- errno = ENOSYS;
- return -1;
-}
-
-
-static int
-__atomic_dec_if_positive( volatile unsigned int* pvalue )
-{
- unsigned int old;
-
- do {
- old = *pvalue;
- }
- while ( old != 0 && __atomic_cmpxchg( (int)old, (int)old-1, (volatile int*)pvalue ) != 0 );
-
- return old;
-}
-
-int sem_wait(sem_t *sem)
-{
- if (sem == NULL) {
- errno = EINVAL;
- return -1;
- }
-
- for (;;) {
- if (__atomic_dec_if_positive(&sem->count))
- break;
-
- __futex_wait(&sem->count, 0, 0);
- }
- return 0;
-}
-
-int sem_timedwait(sem_t *sem, const struct timespec *abs_timeout)
-{
- int ret;
-
- if (sem == NULL) {
- errno = EINVAL;
- return -1;
- }
-
- /* POSIX says we need to try to decrement the semaphore
- * before checking the timeout value */
- if (__atomic_dec_if_positive(&sem->count))
- return 0;
-
- /* check it as per Posix */
- if (abs_timeout == NULL ||
- abs_timeout->tv_sec < 0 ||
- abs_timeout->tv_nsec < 0 ||
- abs_timeout->tv_nsec >= 1000000000)
- {
- errno = EINVAL;
- return -1;
- }
-
- for (;;) {
- struct timespec ts;
- int ret;
-
- /* Posix mandates CLOCK_REALTIME here */
- clock_gettime( CLOCK_REALTIME, &ts );
- ts.tv_sec = abs_timeout->tv_sec - ts.tv_sec;
- ts.tv_nsec = abs_timeout->tv_nsec - ts.tv_nsec;
- if (ts.tv_nsec < 0) {
- ts.tv_nsec += 1000000000;
- ts.tv_sec -= 1;
- }
-
- if (ts.tv_sec < 0 || ts.tv_nsec < 0) {
- errno = ETIMEDOUT;
- return -1;
- }
-
- ret = __futex_wait(&sem->count, 0, &ts);
-
- /* return in case of timeout or interrupt */
- if (ret == -ETIMEDOUT || ret == -EINTR) {
- errno = -ret;
- return -1;
- }
-
- if (__atomic_dec_if_positive(&sem->count))
- break;
- }
- return 0;
-}
-
-int sem_post(sem_t *sem)
-{
- if (sem == NULL)
- return EINVAL;
-
- if (__atomic_inc((volatile int*)&sem->count) == 0)
- __futex_wake(&sem->count, 1);
-
- return 0;
-}
-
-int sem_trywait(sem_t *sem)
-{
- if (sem == NULL) {
- errno = EINVAL;
- return -1;
- }
-
- if (__atomic_dec_if_positive(&sem->count) > 0) {
- return 0;
- } else {
- return EAGAIN;
- }
-}
-
-int sem_getvalue(sem_t *sem, int *sval)
-{
- if (sem == NULL || sval == NULL) {
- errno = EINVAL;
- return -1;
- }
-
- *sval = sem->count;
- return 0;
-}