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-rw-r--r--lib/libc/gen/sem_new.c441
1 files changed, 0 insertions, 441 deletions
diff --git a/lib/libc/gen/sem_new.c b/lib/libc/gen/sem_new.c
deleted file mode 100644
index 2698b40..0000000
--- a/lib/libc/gen/sem_new.c
+++ /dev/null
@@ -1,441 +0,0 @@
-/*
- * Copyright (C) 2010 David Xu <davidxu@freebsd.org>.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice(s), this list of conditions and the following disclaimer as
- * the first lines of this file unmodified other than the possible
- * addition of one or more copyright notices.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice(s), 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 HOLDER(S) ``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 HOLDER(S) 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.
- *
- * $FreeBSD$
- */
-
-#include "namespace.h"
-#include <sys/types.h>
-#include <sys/queue.h>
-#include <sys/mman.h>
-#include <sys/stat.h>
-#include <errno.h>
-#include <machine/atomic.h>
-#include <sys/umtx.h>
-#include <limits.h>
-#include <fcntl.h>
-#include <pthread.h>
-#include <stdarg.h>
-#include <stdlib.h>
-#include <string.h>
-#include <time.h>
-#include <semaphore.h>
-#include <unistd.h>
-#include "un-namespace.h"
-#include "libc_private.h"
-
-__weak_reference(_sem_close, sem_close);
-__weak_reference(_sem_destroy, sem_destroy);
-__weak_reference(_sem_getvalue, sem_getvalue);
-__weak_reference(_sem_init, sem_init);
-__weak_reference(_sem_open, sem_open);
-__weak_reference(_sem_post, sem_post);
-__weak_reference(_sem_timedwait, sem_timedwait);
-__weak_reference(_sem_trywait, sem_trywait);
-__weak_reference(_sem_unlink, sem_unlink);
-__weak_reference(_sem_wait, sem_wait);
-
-#define SEM_PREFIX "/tmp/SEMD"
-#define SEM_MAGIC ((u_int32_t)0x73656d31)
-
-struct sem_nameinfo {
- int open_count;
- char *name;
- sem_t *sem;
- LIST_ENTRY(sem_nameinfo) next;
-};
-
-static pthread_once_t once = PTHREAD_ONCE_INIT;
-static pthread_mutex_t sem_llock;
-static LIST_HEAD(,sem_nameinfo) sem_list = LIST_HEAD_INITIALIZER(sem_list);
-
-static void
-sem_prefork()
-{
-
- _pthread_mutex_lock(&sem_llock);
-}
-
-static void
-sem_postfork()
-{
- _pthread_mutex_unlock(&sem_llock);
-}
-
-static void
-sem_child_postfork()
-{
- _pthread_mutex_unlock(&sem_llock);
-}
-
-static void
-sem_module_init(void)
-{
- pthread_mutexattr_t ma;
-
- _pthread_mutexattr_init(&ma);
- _pthread_mutexattr_settype(&ma, PTHREAD_MUTEX_RECURSIVE);
- _pthread_mutex_init(&sem_llock, &ma);
- _pthread_mutexattr_destroy(&ma);
- _pthread_atfork(sem_prefork, sem_postfork, sem_child_postfork);
-}
-
-static inline int
-sem_check_validity(sem_t *sem)
-{
-
- if (sem->_magic == SEM_MAGIC)
- return (0);
- else {
- errno = EINVAL;
- return (-1);
- }
-}
-
-int
-_sem_init(sem_t *sem, int pshared, unsigned int value)
-{
-
- if (value > SEM_VALUE_MAX) {
- errno = EINVAL;
- return (-1);
- }
-
- bzero(sem, sizeof(sem_t));
- sem->_magic = SEM_MAGIC;
- sem->_kern._count = (u_int32_t)value;
- sem->_kern._has_waiters = 0;
- sem->_kern._flags = pshared ? USYNC_PROCESS_SHARED : 0;
- return (0);
-}
-
-sem_t *
-_sem_open(const char *name, int flags, ...)
-{
- char path[PATH_MAX];
-
- struct stat sb;
- va_list ap;
- struct sem_nameinfo *ni = NULL;
- sem_t *sem = NULL;
- int fd = -1, mode, len, errsave;
- int value = 0;
-
- if (name[0] != '/') {
- errno = EINVAL;
- return (SEM_FAILED);
- }
- name++;
-
- if (flags & ~(O_CREAT|O_EXCL)) {
- errno = EINVAL;
- return (SEM_FAILED);
- }
-
- _pthread_once(&once, sem_module_init);
-
- _pthread_mutex_lock(&sem_llock);
- LIST_FOREACH(ni, &sem_list, next) {
- if (strcmp(name, ni->name) == 0) {
- ni->open_count++;
- sem = ni->sem;
- _pthread_mutex_unlock(&sem_llock);
- return (sem);
- }
- }
-
- if (flags & O_CREAT) {
- va_start(ap, flags);
- mode = va_arg(ap, int);
- value = va_arg(ap, int);
- va_end(ap);
- }
-
- len = sizeof(*ni) + strlen(name) + 1;
- ni = (struct sem_nameinfo *)malloc(len);
- if (ni == NULL) {
- errno = ENOSPC;
- goto error;
- }
-
- ni->name = (char *)(ni+1);
- strcpy(ni->name, name);
-
- strcpy(path, SEM_PREFIX);
- if (strlcat(path, name, sizeof(path)) >= sizeof(path)) {
- errno = ENAMETOOLONG;
- goto error;
- }
-
- fd = _open(path, flags|O_RDWR, mode);
- if (fd == -1)
- goto error;
- if (flock(fd, LOCK_EX) == -1)
- goto error;
- if (_fstat(fd, &sb)) {
- flock(fd, LOCK_UN);
- goto error;
- }
- if (sb.st_size < sizeof(sem_t)) {
- sem_t tmp;
-
- tmp._magic = SEM_MAGIC;
- tmp._kern._has_waiters = 0;
- tmp._kern._count = value;
- tmp._kern._flags = USYNC_PROCESS_SHARED | SEM_NAMED;
- if (_write(fd, &tmp, sizeof(tmp)) != sizeof(tmp)) {
- flock(fd, LOCK_UN);
- goto error;
- }
- }
- flock(fd, LOCK_UN);
- sem = (sem_t *)mmap(NULL, sizeof(sem_t), PROT_READ|PROT_WRITE,
- MAP_SHARED|MAP_NOSYNC, fd, 0);
- if (sem == MAP_FAILED) {
- sem = NULL;
- if (errno == ENOMEM)
- errno = ENOSPC;
- goto error;
- }
- if (sem->_magic != SEM_MAGIC) {
- errno = EINVAL;
- goto error;
- }
- ni->open_count = 1;
- ni->sem = sem;
- LIST_INSERT_HEAD(&sem_list, ni, next);
- _pthread_mutex_unlock(&sem_llock);
- _close(fd);
- return (sem);
-
-error:
- errsave = errno;
- _pthread_mutex_unlock(&sem_llock);
- if (fd != -1)
- _close(fd);
- if (sem != NULL)
- munmap(sem, sizeof(sem_t));
- free(ni);
- errno = errsave;
- return (SEM_FAILED);
-}
-
-int
-_sem_close(sem_t *sem)
-{
- struct sem_nameinfo *ni;
-
- if (sem_check_validity(sem) != 0)
- return (-1);
-
- if (!(sem->_kern._flags & SEM_NAMED)) {
- errno = EINVAL;
- return (-1);
- }
-
- _pthread_once(&once, sem_module_init);
-
- _pthread_mutex_lock(&sem_llock);
- LIST_FOREACH(ni, &sem_list, next) {
- if (sem == ni->sem) {
- if (--ni->open_count > 0) {
- _pthread_mutex_unlock(&sem_llock);
- return (0);
- }
- else
- break;
- }
- }
-
- if (ni) {
- LIST_REMOVE(ni, next);
- _pthread_mutex_unlock(&sem_llock);
- munmap(sem, sizeof(*sem));
- free(ni);
- return (0);
- }
- _pthread_mutex_unlock(&sem_llock);
- errno = EINVAL;
- return (-1);
-}
-
-int
-_sem_unlink(const char *name)
-{
- char path[PATH_MAX];
-
- if (name[0] != '/') {
- errno = ENOENT;
- return -1;
- }
- name++;
-
- strcpy(path, SEM_PREFIX);
- if (strlcat(path, name, sizeof(path)) >= sizeof(path)) {
- errno = ENAMETOOLONG;
- return (-1);
- }
- return unlink(path);
-}
-
-int
-_sem_destroy(sem_t *sem)
-{
-
- if (sem_check_validity(sem) != 0)
- return (-1);
-
- if (sem->_kern._flags & SEM_NAMED) {
- errno = EINVAL;
- return (-1);
- }
- sem->_magic = 0;
- return (0);
-}
-
-int
-_sem_getvalue(sem_t * __restrict sem, int * __restrict sval)
-{
-
- if (sem_check_validity(sem) != 0)
- return (-1);
-
- *sval = (int)sem->_kern._count;
- return (0);
-}
-
-static __inline int
-usem_wake(struct _usem *sem)
-{
- if (!sem->_has_waiters)
- return (0);
- return _umtx_op(sem, UMTX_OP_SEM_WAKE, 0, NULL, NULL);
-}
-
-static __inline int
-usem_wait(struct _usem *sem, const struct timespec *timeout)
-{
- if (timeout && (timeout->tv_sec < 0 || (timeout->tv_sec == 0 &&
- timeout->tv_nsec <= 0))) {
- errno = ETIMEDOUT;
- return (-1);
- }
- return _umtx_op(sem, UMTX_OP_SEM_WAIT, 0, NULL,
- __DECONST(void*, timeout));
-}
-
-int
-_sem_trywait(sem_t *sem)
-{
- int val;
-
- if (sem_check_validity(sem) != 0)
- return (-1);
-
- while ((val = sem->_kern._count) > 0) {
- if (atomic_cmpset_acq_int(&sem->_kern._count, val, val - 1))
- return (0);
- }
- errno = EAGAIN;
- return (-1);
-}
-
-#define TIMESPEC_SUB(dst, src, val) \
- do { \
- (dst)->tv_sec = (src)->tv_sec - (val)->tv_sec; \
- (dst)->tv_nsec = (src)->tv_nsec - (val)->tv_nsec; \
- if ((dst)->tv_nsec < 0) { \
- (dst)->tv_sec--; \
- (dst)->tv_nsec += 1000000000; \
- } \
- } while (0)
-
-
-int
-_sem_timedwait(sem_t * __restrict sem,
- const struct timespec * __restrict abstime)
-{
- struct timespec ts, ts2;
- int val, retval;
-
- if (sem_check_validity(sem) != 0)
- return (-1);
-
- retval = 0;
- for (;;) {
- while ((val = sem->_kern._count) > 0) {
- if (atomic_cmpset_acq_int(&sem->_kern._count, val, val - 1))
- return (0);
- }
-
- if (retval) {
- _pthread_testcancel();
- break;
- }
-
- /*
- * The timeout argument is only supposed to
- * be checked if the thread would have blocked.
- */
- if (abstime != NULL) {
- if (abstime->tv_nsec >= 1000000000 || abstime->tv_nsec < 0) {
- errno = EINVAL;
- return (-1);
- }
- clock_gettime(CLOCK_REALTIME, &ts);
- TIMESPEC_SUB(&ts2, abstime, &ts);
- }
- _pthread_cancel_enter(1);
- retval = usem_wait(&sem->_kern, abstime ? &ts2 : NULL);
- _pthread_cancel_leave(0);
- }
- return (retval);
-}
-
-int
-_sem_wait(sem_t *sem)
-{
- return _sem_timedwait(sem, NULL);
-}
-
-/*
- * POSIX:
- * The sem_post() interface is reentrant with respect to signals and may be
- * invoked from a signal-catching function.
- * The implementation does not use lock, so it should be safe.
- */
-int
-_sem_post(sem_t *sem)
-{
-
- if (sem_check_validity(sem) != 0)
- return (-1);
-
- atomic_add_rel_int(&sem->_kern._count, 1);
- return usem_wake(&sem->_kern);
-}
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