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      1 #ifndef _LINUX_MSG_H
      2 #define _LINUX_MSG_H
      3 
      4 #include <linux/ipc.h>
      5 
      6 /* ipcs ctl commands */
      7 #define MSG_STAT 11
      8 #define MSG_INFO 12
      9 
     10 /* msgrcv options */
     11 #define MSG_NOERROR     010000  /* no error if message is too big */
     12 #define MSG_EXCEPT      020000  /* recv any msg except of specified type.*/
     13 
     14 /* Obsolete, used only for backwards compatibility and libc5 compiles */
     15 struct msqid_ds {
     16 	struct ipc_perm msg_perm;
     17 	struct msg *msg_first;		/* first message on queue,unused  */
     18 	struct msg *msg_last;		/* last message in queue,unused */
     19 	__kernel_time_t msg_stime;	/* last msgsnd time */
     20 	__kernel_time_t msg_rtime;	/* last msgrcv time */
     21 	__kernel_time_t msg_ctime;	/* last change time */
     22 	unsigned long  msg_lcbytes;	/* Reuse junk fields for 32 bit */
     23 	unsigned long  msg_lqbytes;	/* ditto */
     24 	unsigned short msg_cbytes;	/* current number of bytes on queue */
     25 	unsigned short msg_qnum;	/* number of messages in queue */
     26 	unsigned short msg_qbytes;	/* max number of bytes on queue */
     27 	__kernel_ipc_pid_t msg_lspid;	/* pid of last msgsnd */
     28 	__kernel_ipc_pid_t msg_lrpid;	/* last receive pid */
     29 };
     30 
     31 /* Include the definition of msqid64_ds */
     32 #include <asm/msgbuf.h>
     33 
     34 /* message buffer for msgsnd and msgrcv calls */
     35 struct msgbuf {
     36 	long mtype;         /* type of message */
     37 	char mtext[1];      /* message text */
     38 };
     39 
     40 /* buffer for msgctl calls IPC_INFO, MSG_INFO */
     41 struct msginfo {
     42 	int msgpool;
     43 	int msgmap;
     44 	int msgmax;
     45 	int msgmnb;
     46 	int msgmni;
     47 	int msgssz;
     48 	int msgtql;
     49 	unsigned short  msgseg;
     50 };
     51 
     52 #define MSGMNI    16   /* <= IPCMNI */     /* max # of msg queue identifiers */
     53 #define MSGMAX  8192   /* <= INT_MAX */   /* max size of message (bytes) */
     54 #define MSGMNB 16384   /* <= INT_MAX */   /* default max size of a message queue */
     55 
     56 /* unused */
     57 #define MSGPOOL (MSGMNI*MSGMNB/1024)  /* size in kilobytes of message pool */
     58 #define MSGTQL  MSGMNB            /* number of system message headers */
     59 #define MSGMAP  MSGMNB            /* number of entries in message map */
     60 #define MSGSSZ  16                /* message segment size */
     61 #define __MSGSEG ((MSGPOOL*1024)/ MSGSSZ) /* max no. of segments */
     62 #define MSGSEG (__MSGSEG <= 0xffff ? __MSGSEG : 0xffff)
     63 
     64 #ifdef __KERNEL__
     65 #include <linux/list.h>
     66 
     67 /* one msg_msg structure for each message */
     68 struct msg_msg {
     69 	struct list_head m_list;
     70 	long  m_type;
     71 	int m_ts;           /* message text size */
     72 	struct msg_msgseg* next;
     73 	void *security;
     74 	/* the actual message follows immediately */
     75 };
     76 
     77 /* one msq_queue structure for each present queue on the system */
     78 struct msg_queue {
     79 	struct kern_ipc_perm q_perm;
     80 	int q_id;
     81 	time_t q_stime;			/* last msgsnd time */
     82 	time_t q_rtime;			/* last msgrcv time */
     83 	time_t q_ctime;			/* last change time */
     84 	unsigned long q_cbytes;		/* current number of bytes on queue */
     85 	unsigned long q_qnum;		/* number of messages in queue */
     86 	unsigned long q_qbytes;		/* max number of bytes on queue */
     87 	pid_t q_lspid;			/* pid of last msgsnd */
     88 	pid_t q_lrpid;			/* last receive pid */
     89 
     90 	struct list_head q_messages;
     91 	struct list_head q_receivers;
     92 	struct list_head q_senders;
     93 };
     94 
     95 #endif /* __KERNEL__ */
     96 
     97 #endif /* _LINUX_MSG_H */
     98