Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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 */
15struct 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 */
35struct msgbuf {
36 long mtype; /* type of message */
37 char mtext[1]; /* message text */
38};
39
40/* buffer for msgctl calls IPC_INFO, MSG_INFO */
41struct 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 */
68struct 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 */
78struct msg_queue {
79 struct kern_ipc_perm q_perm;
80 time_t q_stime; /* last msgsnd time */
81 time_t q_rtime; /* last msgrcv time */
82 time_t q_ctime; /* last change time */
83 unsigned long q_cbytes; /* current number of bytes on queue */
84 unsigned long q_qnum; /* number of messages in queue */
85 unsigned long q_qbytes; /* max number of bytes on queue */
86 pid_t q_lspid; /* pid of last msgsnd */
87 pid_t q_lrpid; /* last receive pid */
88
89 struct list_head q_messages;
90 struct list_head q_receivers;
91 struct list_head q_senders;
92};
93
94/* Helper routines for sys_msgsnd and sys_msgrcv */
95extern long do_msgsnd(int msqid, long mtype, void __user *mtext,
96 size_t msgsz, int msgflg);
97extern long do_msgrcv(int msqid, long *pmtype, void __user *mtext,
98 size_t msgsz, long msgtyp, int msgflg);
99
100#endif /* __KERNEL__ */
101
102#endif /* _LINUX_MSG_H */