glibc/sysdeps/unix/sysv/linux/bits/shm.h

119 lines
3.8 KiB
C

/* Copyright (C) 1995-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library 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 2.1 of the License, or (at your option) any later version.
The GNU C Library 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 the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#ifndef _SYS_SHM_H
# error "Never include <bits/shm.h> directly; use <sys/shm.h> instead."
#endif
#include <bits/types.h>
#include <bits/wordsize.h>
#include <bits/shmlba.h>
#include <bits/shm-pad.h>
/* Permission flag for shmget. */
#define SHM_R 0400 /* or S_IRUGO from <linux/stat.h> */
#define SHM_W 0200 /* or S_IWUGO from <linux/stat.h> */
/* Flags for `shmat'. */
#define SHM_RDONLY 010000 /* attach read-only else read-write */
#define SHM_RND 020000 /* round attach address to SHMLBA */
#define SHM_REMAP 040000 /* take-over region on attach */
#define SHM_EXEC 0100000 /* execution access */
/* Commands for `shmctl'. */
#define SHM_LOCK 11 /* lock segment (root only) */
#define SHM_UNLOCK 12 /* unlock segment (root only) */
__BEGIN_DECLS
/* Type to count number of attaches. */
typedef __syscall_ulong_t shmatt_t;
#if __SHM_PAD_BEFORE_TIME
# define __SHM_PAD_TIME(NAME, RES) \
unsigned long int __glibc_reserved ## RES; __time_t NAME
#elif __SHM_PAD_AFTER_TIME
# define __SHM_PAD_TIME(NAME, RES) \
__time_t NAME; unsigned long int __glibc_reserved ## RES
#else
# define __SHM_PAD_TIME(NAME, RES) \
__time_t NAME
#endif
/* Data structure describing a shared memory segment. */
struct shmid_ds
{
struct ipc_perm shm_perm; /* operation permission struct */
#if !__SHM_SEGSZ_AFTER_TIME
size_t shm_segsz; /* size of segment in bytes */
#endif
__SHM_PAD_TIME (shm_atime, 1); /* time of last shmat() */
__SHM_PAD_TIME (shm_dtime, 2); /* time of last shmdt() */
__SHM_PAD_TIME (shm_ctime, 3); /* time of last change by shmctl() */
#if __SHM_PAD_BETWEEN_TIME_AND_SEGSZ
unsigned long int __glibc_reserved4;
#endif
#if __SHM_SEGSZ_AFTER_TIME
size_t shm_segsz; /* size of segment in bytes */
#endif
__pid_t shm_cpid; /* pid of creator */
__pid_t shm_lpid; /* pid of last shmop */
shmatt_t shm_nattch; /* number of current attaches */
__syscall_ulong_t __glibc_reserved5;
__syscall_ulong_t __glibc_reserved6;
};
#ifdef __USE_MISC
/* ipcs ctl commands */
# define SHM_STAT 13
# define SHM_INFO 14
# define SHM_STAT_ANY 15
/* shm_mode upper byte flags */
# define SHM_DEST 01000 /* segment will be destroyed on last detach */
# define SHM_LOCKED 02000 /* segment will not be swapped */
# define SHM_HUGETLB 04000 /* segment is mapped via hugetlb */
# define SHM_NORESERVE 010000 /* don't check for reservations */
struct shminfo
{
__syscall_ulong_t shmmax;
__syscall_ulong_t shmmin;
__syscall_ulong_t shmmni;
__syscall_ulong_t shmseg;
__syscall_ulong_t shmall;
__syscall_ulong_t __glibc_reserved1;
__syscall_ulong_t __glibc_reserved2;
__syscall_ulong_t __glibc_reserved3;
__syscall_ulong_t __glibc_reserved4;
};
struct shm_info
{
int used_ids;
__syscall_ulong_t shm_tot; /* total allocated shm */
__syscall_ulong_t shm_rss; /* total resident shm */
__syscall_ulong_t shm_swp; /* total swapped shm */
__syscall_ulong_t swap_attempts;
__syscall_ulong_t swap_successes;
};
#endif /* __USE_MISC */
__END_DECLS