sem.h

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#ifndef _UAPI_LINUX_SEM_H
#define _UAPI_LINUX_SEM_H

#include <linux/ipc.h>

/* semop flags */
#define SEM_UNDO        0x1000  /* undo the operation on exit */

/* semctl Command Definitions. */
#define GETPID  11       /* get sempid */
#define GETVAL  12       /* get semval */
#define GETALL  13       /* get all semval's */
#define GETNCNT 14       /* get semncnt */
#define GETZCNT 15       /* get semzcnt */
#define SETVAL  16       /* set semval */
#define SETALL  17       /* set all semval's */

/* ipcs ctl cmds */
#define SEM_STAT 18
#define SEM_INFO 19

/* Obsolete, used only for backwards compatibility and libc5 compiles */
struct semid_ds {
    struct ipc_perm sem_perm;       /* permissions .. see ipc.h */
    __kernel_time_t sem_otime;      /* last semop time */
    __kernel_time_t sem_ctime;      /* last change time */
    struct sem  *sem_base;      /* ptr to first semaphore in array */
    struct sem_queue *sem_pending;      /* pending operations to be processed */
    struct sem_queue **sem_pending_last;    /* last pending operation */
    struct sem_undo *undo;          /* undo requests on this array */
    unsigned short  sem_nsems;      /* no. of semaphores in array */
};

/* Include the definition of semid64_ds */
#include <asm/sembuf.h>

/* semop system calls takes an array of these. */
struct sembuf {
    unsigned short  sem_num;    /* semaphore index in array */
    short       sem_op;     /* semaphore operation */
    short       sem_flg;    /* operation flags */
};

/* arg for semctl system calls. */
union semun {
    int val;            /* value for SETVAL */
    struct semid_ds __user *buf;    /* buffer for IPC_STAT & IPC_SET */
    unsigned short __user *array;   /* array for GETALL & SETALL */
    struct seminfo __user *__buf;   /* buffer for IPC_INFO */
    void __user *__pad;
};

struct  seminfo {
    int semmap;
    int semmni;
    int semmns;
    int semmnu;
    int semmsl;
    int semopm;
    int semume;
    int semusz;
    int semvmx;
    int semaem;
};

#define SEMMNI  128             /* <= IPCMNI  max # of semaphore identifiers */
#define SEMMSL  250             /* <= 8 000 max num of semaphores per id */
#define SEMMNS  (SEMMNI*SEMMSL) /* <= INT_MAX max # of semaphores in system */
#define SEMOPM  32          /* <= 1 000 max num of ops per semop call */
#define SEMVMX  32767           /* <= 32767 semaphore maximum value */
#define SEMAEM  SEMVMX          /* adjust on exit max value */

/* unused */
#define SEMUME  SEMOPM          /* max num of undo entries per process */
#define SEMMNU  SEMMNS          /* num of undo structures system wide */
#define SEMMAP  SEMMNS          /* # of entries in semaphore map */
#define SEMUSZ  20      /* sizeof struct sem_undo */


#endif /* _UAPI_LINUX_SEM_H */