1/* $NetBSD: sem.h,v 1.37 2025/05/09 10:22:55 martin 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
209void do_semop_init(void);
210int do_semop1(struct lwp*, int, struct sembuf*, size_t, struct timespec*, register_t*);
211
212#endif /* _KERNEL */
213
214#ifndef _KERNEL
215#include <sys/cdefs.h>
216
217__BEGIN_DECLS
218#ifndef __LIBC12_SOURCE__
219int semctl(int, int, int, ...) __RENAME(__semctl50);
220#endif
221int semget(key_t, int, int);
222int semop(int, struct sembuf *, size_t);
223struct timespec;
224int semtimedop(int, struct sembuf *, size_t, struct timespec *);
225#if defined(_NETBSD_SOURCE)
226int semconfig(int);
227#endif
228__END_DECLS
229#else
230int seminit(void);
231int semfini(void);
232void semexit(struct proc *, void *);
233
234int semctl1(struct lwp *, int, int, int, void *, register_t *);
235#define get_semctl_arg(cmd, sembuf, arg) \
236 ((cmd) == IPC_SET || (cmd) == IPC_STAT ? (void *)sembuf \
237 : (cmd) == GETALL || (cmd) == SETVAL || (cmd) == SETALL ? (void *)arg \
238 : NULL)
239#endif /* !_KERNEL */
240
241#endif /* !_SYS_SEM_H_ */