usr/src/uts/common/sys/vuid_queue.h

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 1985,1997-1998 by Sun Microsystems, Inc.
  24  * All rights reserved.
  25  */
  26
  27 /*
  28  * This file describes a virtual user input device (vuid) event queue
  29  * maintainence package (see ../sundev/vuid_event.h for a description
  30  * of what vuid is).  This header file defines the interface that a
  31  * client of this package sees.  This package is used to maintain queues
  32  * of firm events awaiting deliver to some consumer.
  33  */
  34
  35 #ifndef _SYS_VUID_QUEUE_H
  36 #define _SYS_VUID_QUEUE_H
  37
  38 #pragma ident   "%Z%%M% %I%     %E% SMI"        /* SunOS 1.6 */
  39
  40 #ifdef  __cplusplus
  41 extern "C" {
  42 #endif
  43
  44 /*
  45  * Vuid input queue structure.
  46  */
  47 typedef struct  vuid_queue {
  48         struct  vuid_q_node *top;       /* input queue head (first in line) */
  49         struct  vuid_q_node *bottom;    /* input queue head (last in line) */
  50         struct  vuid_q_node *free;      /* input queue free list */
  51         int     num;                    /* number of items currently on queue */
  52         int     size;                   /* number of items allowed on queue */
  53 } Vuid_queue;
  54 #define VUID_QUEUE_NULL ((Vuid_queue *)0)
  55 #define vq_used(vq) ((vq)->num)
  56 #define vq_avail(vq) ((vq)->size - (vq)->num)
  57 #define vq_size(vq) ((vq)->size)
  58 #define vq_is_empty(vq) ((vq)->top == VUID_Q_NODE_NULL)
  59 #define vq_is_full(vq) ((vq)->num == (vq)->size)
  60
  61 /*
  62  * Vuid input queue node structure.
  63  */
  64 typedef struct  vuid_q_node {
  65         struct  vuid_q_node *next;      /* Next item in queue */
  66         struct  vuid_q_node *prev;      /* Previous item in queue */
  67         Firm_event firm_event;          /* Firm event */
  68 } Vuid_q_node;
  69 #define VUID_Q_NODE_NULL        ((Vuid_q_node *)0)
  70
  71 /*
  72  * Vuid input queue status codes.
  73  */
  74 typedef enum    vuid_q_code {
  75         VUID_Q_OK = 0,          /* OK */
  76         VUID_Q_OVERFLOW = 1,    /* overflow */
  77         VUID_Q_EMPTY = 2        /* empty */
  78 } Vuid_q_code;
  79
  80 extern  void vq_initialize(); /* (Vuid_queue *vq, caddr_t data, uint_t bytes) */
  81                                 /* Client allocates bytes worth of storage */
  82                                 /* and pass in a data. Client destroys the q */
  83                                 /* simply by releasing data. */
  84 extern  Vuid_q_code vq_put();   /* (Vuid_queue *vq, Firm_event *firm_event) */
  85                                 /* Place firm_event on queue, position is */
  86                                 /* dependent on the firm event's time.  Can */
  87                                 /* return VUID_Q_OVERFLOW if no more room. */
  88 extern  Vuid_q_code vq_get();   /* (Vuid_queue *vq, Firm_event *firm_event) */
  89                                 /* Place event on top of queue in firm_event. */
  90                                 /* Can return VUID_Q_EMPTY if no more events */
  91 extern  Vuid_q_code vq_peek();  /* Like vq_get but doesn't remove from queue */
  92 extern  Vuid_q_code vq_putback(); /* (Vuid_queue *vq, Firm_event *firm_event) */
  93                                 /* Push firm_event on top of queue.  Can */
  94                                 /* return VUID_Q_OVERFLOW if no more room. */
  95
  96 extern  int vq_compress();      /* (Vuid_queue *vq, factor)  Try to */
  97                                 /* collapse the queue to a size of 1/factor */
  98                                 /* by squeezing like valuator events together */
  99                                 /* Returns number collapsed */
 100 extern  int vq_is_valuator();   /* (Vuid_q_node *vqn) if value is not 0 or 1 */
 101                                 /* || pair_type is FE_PAIR_DELTA or */
 102                                 /* FE_PAIR_ABSOLUTE */
 103 extern  void vq_delete_node();  /* (Vuid_queue *vq, Vuid_q_node *vqn) */
 104                                 /* Deletes vqn from vq */
 105
 106 #ifdef  __cplusplus
 107 }
 108 #endif
 109
 110 #endif  /* _SYS_VUID_QUEUE_H */