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 2002 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 #pragma ident "%Z%%M% %I% %E% SMI"
28
29 /*
30 * Routines for manipulating a FIFO queue
31 */
32
33 #include <stdlib.h>
34
35 #include "fifo.h"
36 #include "memory.h"
37
38 typedef struct fifonode {
39 void *fn_data;
40 struct fifonode *fn_next;
41 } fifonode_t;
42
43 struct fifo {
44 fifonode_t *f_head;
45 fifonode_t *f_tail;
46 };
47
48 fifo_t *
fifo_new(void)49 fifo_new(void)
50 {
51 fifo_t *f;
52
53 f = xcalloc(sizeof (fifo_t));
54
55 return (f);
56 }
57
58 /* Add to the end of the fifo */
59 void
fifo_add(fifo_t * f,void * data)60 fifo_add(fifo_t *f, void *data)
61 {
62 fifonode_t *fn = xmalloc(sizeof (fifonode_t));
63
64 fn->fn_data = data;
65 fn->fn_next = NULL;
66
67 if (f->f_tail == NULL)
68 f->f_head = f->f_tail = fn;
69 else {
70 f->f_tail->fn_next = fn;
71 f->f_tail = fn;
72 }
73 }
74
75 /* Remove from the front of the fifo */
76 void *
fifo_remove(fifo_t * f)77 fifo_remove(fifo_t *f)
78 {
79 fifonode_t *fn;
80 void *data;
81
82 if ((fn = f->f_head) == NULL)
83 return (NULL);
84
85 data = fn->fn_data;
86 if ((f->f_head = fn->fn_next) == NULL)
87 f->f_tail = NULL;
88
89 free(fn);
90
91 return (data);
92 }
93
94 /*ARGSUSED*/
95 static void
fifo_nullfree(void * arg)96 fifo_nullfree(void *arg)
97 {
98 /* this function intentionally left blank */
99 }
100
101 /* Free an entire fifo */
102 void
fifo_free(fifo_t * f,void (* freefn)(void *))103 fifo_free(fifo_t *f, void (*freefn)(void *))
104 {
105 fifonode_t *fn = f->f_head;
106 fifonode_t *tmp;
107
108 if (freefn == NULL)
109 freefn = fifo_nullfree;
110
111 while (fn) {
112 (*freefn)(fn->fn_data);
113
114 tmp = fn;
115 fn = fn->fn_next;
116 free(tmp);
117 }
118
119 free(f);
120 }
121
122 int
fifo_len(fifo_t * f)123 fifo_len(fifo_t *f)
124 {
125 fifonode_t *fn;
126 int i;
127
128 for (i = 0, fn = f->f_head; fn; fn = fn->fn_next, i++);
129
130 return (i);
131 }
132
133 int
fifo_empty(fifo_t * f)134 fifo_empty(fifo_t *f)
135 {
136 return (f->f_head == NULL);
137 }
138
139 int
fifo_iter(fifo_t * f,int (* iter)(void * data,void * arg),void * arg)140 fifo_iter(fifo_t *f, int (*iter)(void *data, void *arg), void *arg)
141 {
142 fifonode_t *fn;
143 int rc;
144 int ret = 0;
145
146 for (fn = f->f_head; fn; fn = fn->fn_next) {
147 if ((rc = iter(fn->fn_data, arg)) < 0)
148 return (-1);
149 ret += rc;
150 }
151
152 return (ret);
153 }
154