80 lines
2.0 KiB
C
80 lines
2.0 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* linux/drivers/acorn/scsi/msgqueue.h
|
|
*
|
|
* Copyright (C) 1997 Russell King
|
|
*
|
|
* message queue handling
|
|
*/
|
|
#ifndef MSGQUEUE_H
|
|
#define MSGQUEUE_H
|
|
|
|
struct message {
|
|
char msg[8];
|
|
int length;
|
|
int fifo;
|
|
};
|
|
|
|
struct msgqueue_entry {
|
|
struct message msg;
|
|
struct msgqueue_entry *next;
|
|
};
|
|
|
|
#define NR_MESSAGES 4
|
|
|
|
typedef struct {
|
|
struct msgqueue_entry *qe;
|
|
struct msgqueue_entry *free;
|
|
struct msgqueue_entry entries[NR_MESSAGES];
|
|
} MsgQueue_t;
|
|
|
|
/*
|
|
* Function: void msgqueue_initialise(MsgQueue_t *msgq)
|
|
* Purpose : initialise a message queue
|
|
* Params : msgq - queue to initialise
|
|
*/
|
|
extern void msgqueue_initialise(MsgQueue_t *msgq);
|
|
|
|
/*
|
|
* Function: void msgqueue_free(MsgQueue_t *msgq)
|
|
* Purpose : free a queue
|
|
* Params : msgq - queue to free
|
|
*/
|
|
extern void msgqueue_free(MsgQueue_t *msgq);
|
|
|
|
/*
|
|
* Function: int msgqueue_msglength(MsgQueue_t *msgq)
|
|
* Purpose : calculate the total length of all messages on the message queue
|
|
* Params : msgq - queue to examine
|
|
* Returns : number of bytes of messages in queue
|
|
*/
|
|
extern int msgqueue_msglength(MsgQueue_t *msgq);
|
|
|
|
/*
|
|
* Function: struct message *msgqueue_getmsg(MsgQueue_t *msgq, int msgno)
|
|
* Purpose : return a message & its length
|
|
* Params : msgq - queue to obtain message from
|
|
* : msgno - message number
|
|
* Returns : pointer to message string, or NULL
|
|
*/
|
|
extern struct message *msgqueue_getmsg(MsgQueue_t *msgq, int msgno);
|
|
|
|
/*
|
|
* Function: int msgqueue_addmsg(MsgQueue_t *msgq, int length, ...)
|
|
* Purpose : add a message onto a message queue
|
|
* Params : msgq - queue to add message on
|
|
* length - length of message
|
|
* ... - message bytes
|
|
* Returns : != 0 if successful
|
|
*/
|
|
extern int msgqueue_addmsg(MsgQueue_t *msgq, int length, ...);
|
|
|
|
/*
|
|
* Function: void msgqueue_flush(MsgQueue_t *msgq)
|
|
* Purpose : flush all messages from message queue
|
|
* Params : msgq - queue to flush
|
|
*/
|
|
extern void msgqueue_flush(MsgQueue_t *msgq);
|
|
|
|
#endif
|