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// This file is part of BOINC.
// http://boinc.berkeley.edu
// Copyright (C) 2023 University of California
//
// BOINC is free software; you can redistribute it and/or modify it
// under the terms of the GNU Lesser General Public License
// as published by the Free Software Foundation,
// either version 3 of the License, or (at your option) any later version.
//
// BOINC is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
// See the GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with BOINC. If not, see <http://www.gnu.org/licenses/>.
// interfaces for accessing sempahores
#ifndef ANDROID
#include "config.h"
#include <cstdio>
#include <cstdlib>
#include <cstring>
using std::memset;
#include "boinc_stdio.h"
#include "error_numbers.h"
#include "synch.h"
union SEMUN {
int val;
struct semid_ds *buf;
unsigned short int *arra;
struct seminfo *__buf;
};
int create_semaphore(key_t key){
int id, retval;
SEMUN s;
id = semget(key, 1, IPC_CREAT|IPC_EXCL|0777);
if (id < 0) {
return ERR_SEMGET;
}
memset(&s, 0, sizeof(s));
s.val = 1;
retval = semctl(id, 0, SETVAL, s);
if (retval) {
return ERR_SEMCTL;
}
return 0;
}
int destroy_semaphore(key_t key){
int id, retval;
id = semget(key, 0, 0);
if (id < 0) {
return ERR_SEMGET;
}
retval = semctl(id, 1, IPC_RMID, 0);
if (retval) {
return ERR_SEMCTL;
}
return 0;
}
int lock_semaphore(key_t key) {
struct sembuf s;
int id, retval;
id = semget(key, 0, 0);
if (id < 0) {
return ERR_SEMGET;
}
s.sem_num = 0;
s.sem_op = -1;
s.sem_flg = SEM_UNDO;
retval = semop(id, &s, 1);
if (retval) {
return ERR_SEMOP;
}
return 0;
}
int unlock_semaphore(key_t key) {
struct sembuf s;
int id, retval;
id = semget(key, 0, 0);
if (id < 0) {
return ERR_SEMGET;
}
s.sem_num = 0;
s.sem_op = 1;
s.sem_flg = SEM_UNDO;
retval = semop(id, &s, 1);
if (retval) {
return ERR_SEMOP;
}
return 0;
}
int get_key(char* path, int id, key_t& key) {
key = ftok(path, id);
if (key == (key_t)-1) return ERR_FTOK;
return 0;
}
#endif
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