1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
/****************************************************************************
*
* Open Watcom Project
*
* Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
*
* ========================================================================
*
* This file contains Original Code and/or Modifications of Original
* Code as defined in and that are subject to the Sybase Open Watcom
* Public License version 1.0 (the 'License'). You may not use this file
* except in compliance with the License. BY USING THIS FILE YOU AGREE TO
* ALL TERMS AND CONDITIONS OF THE LICENSE. A copy of the License is
* provided with the Original Code and Modifications, and is also
* available at www.sybase.com/developer/opensource.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND SYBASE AND ALL CONTRIBUTORS HEREBY DISCLAIM
* ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR
* NON-INFRINGEMENT. Please see the License for the specific language
* governing rights and limitations under the License.
*
* ========================================================================
*
* Description: implements queue object
*
****************************************************************************/
#include <stddef.h>
#include "memalloc.h"
#include "queue.h"
#include "myassert.h"
#if 0 /* v2.04: not needed */
void QInit( struct qdesc *q )
/***************************/
{
q->head = NULL;
q->tail = NULL;
}
#endif
void QEnqueue( struct qdesc *q, void *item )
/******************************************/
{
if( q->head == NULL ) {
q->head = q->tail = item;
} else {
/**/ myassert( q->tail != NULL );
*(void **)q->tail = item;
q->tail = item;
}
*(void**)item = NULL;
}
/* add a new node to a queue */
void QAddItem( struct qdesc *q, const void *data )
/************************************************/
{
struct qnode *node;
node = LclAlloc( sizeof( struct qnode ) );
node->elmt = data;
QEnqueue( q, node );
}
#if 0
void QJoinQueue( struct qdesc *dest, struct qdesc *src )
/******************************************************/
{
if( dest->head == NULL ) {
dest->head = src->head;
} else if( src->head == NULL ) {
return;
} else {
/**/ myassert( dest->tail != NULL );
*((void **)dest->tail) = src->head;
}
dest->tail = src->tail;
*(void **)src->tail = NULL;
}
#endif
#if 0 /* v2.04: not needed anymore */
void *QDequeue( struct qdesc *q )
/*******************************/
{
void *item;
if( q->head == NULL ) {
return( NULL );
}
item = q->head;
q->head = *(void**)item;
if( q->head == NULL ) {
q->tail = NULL;
}
return( item );
}
#endif