termux-packages/packages/libandroid-sysv-semaphore/sys_sem.c

80 lines
2.9 KiB
C

/*
* Copyright (C) 2016 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 "sys_sem.h"
#include <stdarg.h>
#include <sys/syscall.h>
#include <unistd.h>
int semctl(int id, int num, int cmd, ...) {
#if !defined(__LP64__)
// Annoyingly, the kernel requires this for 32-bit but rejects it for 64-bit.
cmd |= IPC_64;
#endif
va_list ap;
va_start(ap, cmd);
union semun arg = va_arg(ap, union semun);
va_end(ap);
#if defined(SYS_semctl)
return syscall(SYS_semctl, id, num, cmd, arg);
#else
return syscall(SYS_ipc, SEMCTL, id, num, cmd, &arg, 0);
#endif
}
int semget(key_t key, int n, int flags) {
#if defined(SYS_semget)
return syscall(SYS_semget, key, n, flags);
#else
return syscall(SYS_ipc, SEMGET, key, n, flags, 0, 0);
#endif
}
int semop(int id, struct sembuf* ops, size_t op_count) {
return semtimedop(id, ops, op_count, NULL);
}
int semtimedop(int id, struct sembuf* ops, size_t op_count, const struct timespec* ts) {
#if defined(SYS_semtimedop)
return syscall(SYS_semtimedop, id, ops, op_count, ts);
#else
return syscall(SYS_ipc, SEMTIMEDOP, id, op_count, 0, ops, ts);
#endif
}
/* Make alias for use with e.g. dlopen() */
#undef semctl
int semctl(int id, int num, int cmd, ...) __attribute__((alias("libandroid_semctl")));
#undef semget
int semget(key_t key, int n, int flags) __attribute__((alias("libandroid_semget")));
#undef semop
int semop(int id, struct sembuf* ops, size_t op_count) __attribute__((alias("libandroid_semop")));
#undef semtimedop
int semtimedop(int id, struct sembuf* ops, size_t op_count, const struct timespec* ts) __attribute__((alias("libandroid_semtimedop")));