1/* $NetBSD: sem.h,v 1.35 2024/05/12 10:34:56 rillig Exp $ */ 2 3/*- 4 * Copyright (c) 1999 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33/* 34 * SVID compatible sem.h file 35 * 36 * Author: Daniel Boulet 37 */ 38 39#ifndef _SYS_SEM_H_ 40#define _SYS_SEM_H_ 41 42#include <sys/featuretest.h> 43 44#include <sys/ipc.h> 45 46#ifdef _KERNEL 47struct __sem { 48 unsigned short semval; /* semaphore value */ 49 pid_t sempid; /* pid of last operation */ 50 unsigned short semncnt; /* # awaiting semval > cval */ 51 unsigned short semzcnt; /* # awaiting semval = 0 */ 52}; 53#endif /* _KERNEL */ 54 55struct semid_ds { 56 struct ipc_perm sem_perm; /* operation permission structure */ 57 unsigned short sem_nsems; /* number of semaphores in set */ 58 time_t sem_otime; /* last semop() time */ 59 time_t sem_ctime; /* last time changed by semctl() */ 60 61 /* 62 * These members are private and used only in the internal 63 * implementation of this interface. 64 */ 65 struct __sem *_sem_base; /* pointer to first semaphore in set */ 66}; 67 68/* 69 * semop's sops parameter structure 70 */ 71struct sembuf { 72 unsigned short sem_num; /* semaphore # */ 73 short sem_op; /* semaphore operation */ 74 short sem_flg; /* operation flags */ 75}; 76#define SEM_UNDO 010000 /* undo changes on process exit */ 77 78/* 79 * commands for semctl 80 */ 81#define GETNCNT 3 /* Return the value of semncnt {READ} */ 82#define GETPID 4 /* Return the value of sempid {READ} */ 83#define GETVAL 5 /* Return the value of semval {READ} */ 84#define GETALL 6 /* Return semvals into arg.array {READ} */ 85#define GETZCNT 7 /* Return the value of semzcnt {READ} */ 86#define SETVAL 8 /* Set the value of semval to arg.val {ALTER} */ 87#define SETALL 9 /* Set semvals from arg.array {ALTER} */ 88 89#ifdef _KERNEL 90/* 91 * Kernel implementation stuff 92 */ 93#define SEMVMX 32767 /* semaphore maximum value */ 94#define SEMAEM 16384 /* adjust on exit max value */ 95 96/* 97 * Permissions 98 */ 99#define SEM_A 0200 /* alter permission */ 100#define SEM_R 0400 /* read permission */ 101 102/* 103 * Undo structure (one per process) 104 */ 105struct sem_undo_entry { 106 short un_adjval; /* adjust on exit values */ 107 short un_num; /* semaphore # */ 108 int un_id; /* semid */ 109}; 110 111struct sem_undo { 112 struct sem_undo *un_next; /* ptr to next active undo structure */ 113 struct proc *un_proc; /* owner of this structure */ 114 short un_cnt; /* # of active entries */ 115 struct sem_undo_entry un_ent[1];/* undo entries */ 116}; 117#endif /* _KERNEL */ 118 119#if defined(_NETBSD_SOURCE) 120/* 121 * semaphore info struct 122 */ 123struct seminfo { 124 int32_t semmap; /* # of entries in semaphore map */ 125 int32_t semmni; /* # of semaphore identifiers */ 126 int32_t semmns; /* # of semaphores in system */ 127 int32_t semmnu; /* # of undo structures in system */ 128 int32_t semmsl; /* max # of semaphores per id */ 129 int32_t semopm; /* max # of operations per semop call */ 130 int32_t semume; /* max # of undo entries per process */ 131 int32_t semusz; /* size in bytes of undo structure */ 132 int32_t semvmx; /* semaphore maximum value */ 133 int32_t semaem; /* adjust on exit max value */ 134}; 135 136/* Warning: 64-bit structure padding is needed here */ 137struct semid_ds_sysctl { 138 struct ipc_perm_sysctl sem_perm; 139 int16_t sem_nsems; 140 int16_t pad2; 141 int32_t pad3; 142 time_t sem_otime; 143 time_t sem_ctime; 144}; 145struct sem_sysctl_info { 146 struct seminfo seminfo; 147 struct semid_ds_sysctl semids[1]; 148}; 149 150/* 151 * Internal "mode" bits. The first of these is used by ipcs(1), and so 152 * is defined outside the kernel as well. 153 */ 154#define SEM_ALLOC 01000 /* semaphore is allocated */ 155#endif /* !_POSIX_C_SOURCE && !_XOPEN_SOURCE */ 156 157#ifdef _KERNEL 158#define SEM_DEST 02000 /* semaphore will be destroyed on last detach */ 159 160/* 161 * Configuration parameters 162 */ 163#ifndef SEMMNI 164#define SEMMNI 10 /* # of semaphore identifiers */ 165#endif 166#ifndef SEMMNS 167#define SEMMNS 60 /* # of semaphores in system */ 168#endif 169#ifndef SEMUME 170#define SEMUME 10 /* max # of undo entries per process */ 171#endif 172#ifndef SEMMNU 173#define SEMMNU 30 /* # of undo structures in system */ 174#endif 175 176/* shouldn't need tuning */ 177#ifndef SEMMAP 178#define SEMMAP 30 /* # of entries in semaphore map */ 179#endif 180#ifndef SEMMSL 181#define SEMMSL SEMMNS /* max # of semaphores per id */ 182#endif 183#ifndef SEMOPM 184#define SEMOPM 100 /* max # of operations per semop call */ 185#endif 186 187/* actual size of an undo structure */ 188#define SEMUSZ (sizeof(struct sem_undo)+sizeof(struct sem_undo_entry)*SEMUME) 189 190/* 191 * Structures allocated in machdep.c 192 */ 193extern struct seminfo seminfo; 194extern struct semid_ds *sema; /* semaphore id pool */ 195 196/* 197 * Parameters to the semconfig system call 198 */ 199#define SEM_CONFIG_FREEZE 0 /* Freeze the semaphore facility. */ 200#define SEM_CONFIG_THAW 1 /* Thaw the semaphore facility. */ 201 202#define SYSCTL_FILL_SEM(src, dst) do { \ 203 SYSCTL_FILL_PERM((src).sem_perm, (dst).sem_perm); \ 204 (dst).sem_nsems = (src).sem_nsems; \ 205 (dst).sem_otime = (src).sem_otime; \ 206 (dst).sem_ctime = (src).sem_ctime; \ 207} while (0) 208 209#endif /* _KERNEL */ 210 211#ifndef _KERNEL 212#include <sys/cdefs.h> 213 214__BEGIN_DECLS 215#ifndef __LIBC12_SOURCE__ 216int semctl(int, int, int, ...) __RENAME(__semctl50); 217#endif 218int semget(key_t, int, int); 219int semop(int, struct sembuf *, size_t); 220#if defined(_NETBSD_SOURCE) 221int semconfig(int); 222#endif 223__END_DECLS 224#else 225int seminit(void); 226int semfini(void); 227void semexit(struct proc *, void *); 228 229int semctl1(struct lwp *, int, int, int, void *, register_t *); 230#define get_semctl_arg(cmd, sembuf, arg) \ 231 ((cmd) == IPC_SET || (cmd) == IPC_STAT ? (void *)sembuf \ 232 : (cmd) == GETALL || (cmd) == SETVAL || (cmd) == SETALL ? (void *)arg \ 233 : NULL) 234#endif /* !_KERNEL */ 235 236#endif /* !_SYS_SEM_H_ */ 237