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-rw-r--r--include/uapi/linux/msg.h75
1 files changed, 75 insertions, 0 deletions
diff --git a/include/uapi/linux/msg.h b/include/uapi/linux/msg.h
new file mode 100644
index 000000000000..78dbd2f996a3
--- /dev/null
+++ b/include/uapi/linux/msg.h
@@ -0,0 +1,75 @@
+#ifndef _UAPI_LINUX_MSG_H
+#define _UAPI_LINUX_MSG_H
+
+#include <linux/ipc.h>
+
+/* ipcs ctl commands */
+#define MSG_STAT 11
+#define MSG_INFO 12
+
+/* msgrcv options */
+#define MSG_NOERROR 010000 /* no error if message is too big */
+#define MSG_EXCEPT 020000 /* recv any msg except of specified type.*/
+
+/* Obsolete, used only for backwards compatibility and libc5 compiles */
+struct msqid_ds {
+ struct ipc_perm msg_perm;
+ struct msg *msg_first; /* first message on queue,unused */
+ struct msg *msg_last; /* last message in queue,unused */
+ __kernel_time_t msg_stime; /* last msgsnd time */
+ __kernel_time_t msg_rtime; /* last msgrcv time */
+ __kernel_time_t msg_ctime; /* last change time */
+ unsigned long msg_lcbytes; /* Reuse junk fields for 32 bit */
+ unsigned long msg_lqbytes; /* ditto */
+ unsigned short msg_cbytes; /* current number of bytes on queue */
+ unsigned short msg_qnum; /* number of messages in queue */
+ unsigned short msg_qbytes; /* max number of bytes on queue */
+ __kernel_ipc_pid_t msg_lspid; /* pid of last msgsnd */
+ __kernel_ipc_pid_t msg_lrpid; /* last receive pid */
+};
+
+/* Include the definition of msqid64_ds */
+#include <asm/msgbuf.h>
+
+/* message buffer for msgsnd and msgrcv calls */
+struct msgbuf {
+ long mtype; /* type of message */
+ char mtext[1]; /* message text */
+};
+
+/* buffer for msgctl calls IPC_INFO, MSG_INFO */
+struct msginfo {
+ int msgpool;
+ int msgmap;
+ int msgmax;
+ int msgmnb;
+ int msgmni;
+ int msgssz;
+ int msgtql;
+ unsigned short msgseg;
+};
+
+/*
+ * Scaling factor to compute msgmni:
+ * the memory dedicated to msg queues (msgmni * msgmnb) should occupy
+ * at most 1/MSG_MEM_SCALE of the lowmem (see the formula in ipc/msg.c):
+ * up to 8MB : msgmni = 16 (MSGMNI)
+ * 4 GB : msgmni = 8K
+ * more than 16 GB : msgmni = 32K (IPCMNI)
+ */
+#define MSG_MEM_SCALE 32
+
+#define MSGMNI 16 /* <= IPCMNI */ /* max # of msg queue identifiers */
+#define MSGMAX 8192 /* <= INT_MAX */ /* max size of message (bytes) */
+#define MSGMNB 16384 /* <= INT_MAX */ /* default max size of a message queue */
+
+/* unused */
+#define MSGPOOL (MSGMNI * MSGMNB / 1024) /* size in kbytes of message pool */
+#define MSGTQL MSGMNB /* number of system message headers */
+#define MSGMAP MSGMNB /* number of entries in message map */
+#define MSGSSZ 16 /* message segment size */
+#define __MSGSEG ((MSGPOOL * 1024) / MSGSSZ) /* max no. of segments */
+#define MSGSEG (__MSGSEG <= 0xffff ? __MSGSEG : 0xffff)
+
+
+#endif /* _UAPI_LINUX_MSG_H */