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      1 #ifndef _LINUX_SEM_H
      2 #define _LINUX_SEM_H
      3 
      4 #include <linux/ipc.h>
      5 
      6 /* semop flags */
      7 #define SEM_UNDO        0x1000  /* undo the operation on exit */
      8 
      9 /* semctl Command Definitions. */
     10 #define GETPID  11       /* get sempid */
     11 #define GETVAL  12       /* get semval */
     12 #define GETALL  13       /* get all semval's */
     13 #define GETNCNT 14       /* get semncnt */
     14 #define GETZCNT 15       /* get semzcnt */
     15 #define SETVAL  16       /* set semval */
     16 #define SETALL  17       /* set all semval's */
     17 
     18 /* ipcs ctl cmds */
     19 #define SEM_STAT 18
     20 #define SEM_INFO 19
     21 
     22 /* Obsolete, used only for backwards compatibility and libc5 compiles */
     23 struct semid_ds {
     24 	struct ipc_perm	sem_perm;		/* permissions .. see ipc.h */
     25 	__kernel_time_t	sem_otime;		/* last semop time */
     26 	__kernel_time_t	sem_ctime;		/* last change time */
     27 	struct sem	*sem_base;		/* ptr to first semaphore in array */
     28 	struct sem_queue *sem_pending;		/* pending operations to be processed */
     29 	struct sem_queue **sem_pending_last;	/* last pending operation */
     30 	struct sem_undo	*undo;			/* undo requests on this array */
     31 	unsigned short	sem_nsems;		/* no. of semaphores in array */
     32 };
     33 
     34 /* Include the definition of semid64_ds */
     35 #include <asm/sembuf.h>
     36 
     37 /* semop system calls takes an array of these. */
     38 struct sembuf {
     39 	unsigned short  sem_num;	/* semaphore index in array */
     40 	short		sem_op;		/* semaphore operation */
     41 	short		sem_flg;	/* operation flags */
     42 };
     43 
     44 /* arg for semctl system calls. */
     45 union semun {
     46 	int val;			/* value for SETVAL */
     47 	struct semid_ds *buf;	/* buffer for IPC_STAT & IPC_SET */
     48 	unsigned short *array;	/* array for GETALL & SETALL */
     49 	struct seminfo *__buf;	/* buffer for IPC_INFO */
     50 	void *__pad;
     51 };
     52 
     53 struct  seminfo {
     54 	int semmap;
     55 	int semmni;
     56 	int semmns;
     57 	int semmnu;
     58 	int semmsl;
     59 	int semopm;
     60 	int semume;
     61 	int semusz;
     62 	int semvmx;
     63 	int semaem;
     64 };
     65 
     66 #define SEMMNI  128             /* <= IPCMNI  max # of semaphore identifiers */
     67 #define SEMMSL  250             /* <= 8 000 max num of semaphores per id */
     68 #define SEMMNS  (SEMMNI*SEMMSL) /* <= INT_MAX max # of semaphores in system */
     69 #define SEMOPM  32	        /* <= 1 000 max num of ops per semop call */
     70 #define SEMVMX  32767           /* <= 32767 semaphore maximum value */
     71 #define SEMAEM  SEMVMX          /* adjust on exit max value */
     72 
     73 /* unused */
     74 #define SEMUME  SEMOPM          /* max num of undo entries per process */
     75 #define SEMMNU  SEMMNS          /* num of undo structures system wide */
     76 #define SEMMAP  SEMMNS          /* # of entries in semaphore map */
     77 #define SEMUSZ  20		/* sizeof struct sem_undo */
     78 
     79 
     80 #endif /* _LINUX_SEM_H */
     81