xref: /dragonfly/sbin/udevd/udevd_pdev.c (revision 0c8103dd)
1 /*
2  * Copyright (c) 2010 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Alex Hornung <ahornung@gmail.com>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 #include <sys/types.h>
35 #include <sys/device.h>
36 #include <sys/wait.h>
37 #include <sys/socket.h>
38 #include <sys/ioctl.h>
39 #include <sys/poll.h>
40 #include <sys/queue.h>
41 #include <sys/un.h>
42 
43 #include <err.h>
44 #include <errno.h>
45 #include <fcntl.h>
46 #include <libgen.h>
47 #include <regex.h>
48 #include <signal.h>
49 #include <stdarg.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <syslog.h>
54 #include <unistd.h>
55 #include <pthread.h>
56 
57 #include <libprop/proplib.h>
58 #include <sys/udev.h>
59 #include "udevd.h"
60 
61 static int64_t udev_generation;
62 TAILQ_HEAD(pdev_array_list_head, pdev_array_entry)	pdev_array_list;
63 
64 void
pdev_array_entry_ref(struct pdev_array_entry * pae)65 pdev_array_entry_ref(struct pdev_array_entry *pae)
66 {
67 	++pae->refs;
68 }
69 
70 void
pdev_array_entry_unref(struct pdev_array_entry * pae)71 pdev_array_entry_unref(struct pdev_array_entry *pae)
72 {
73 	if (--pae->refs == 0) {
74 		TAILQ_REMOVE(&pdev_array_list, pae, link);
75 		prop_object_release(pae->pdev_array); /* XXX */
76 		free(pae);
77 	}
78 }
79 
80 void
pdev_array_entry_insert(prop_array_t pa)81 pdev_array_entry_insert(prop_array_t pa)
82 {
83 	struct pdev_array_entry *pae, *opae = NULL;
84 
85 	if (pa == NULL)
86 		errx(1, "null prop_array in insert_pdev_array");
87 	pae = malloc(sizeof(struct pdev_array_entry));
88 	if (pae == NULL)
89 		errx(1, "insert_pdev_array could not allocate mem");
90 	memset(pae, 0, sizeof(struct pdev_array_entry));
91 	pae->pdev_array = pa;
92 	pae->generation = udev_generation++;
93 	pae->refs = 1; /* One ref because it's the most recent one */
94 
95 	/*
96 	 * If the TAILQ is not empty, unref the last entry,
97 	 * as it isn't needed anymore.
98 	 */
99 	if (!TAILQ_EMPTY(&pdev_array_list))
100 		opae = TAILQ_LAST(&pdev_array_list, pdev_array_list_head);
101 
102 	TAILQ_INSERT_TAIL(&pdev_array_list, pae, link);
103 
104 	if (opae != NULL)
105 		pdev_array_entry_unref(opae);
106 }
107 
108 void
pdev_array_clean(void)109 pdev_array_clean(void)
110 {
111 	struct pdev_array_entry *pae;
112 
113 	while ((pae = TAILQ_LAST(&pdev_array_list, pdev_array_list_head)) != NULL) {
114 		TAILQ_REMOVE(&pdev_array_list, pae, link);
115 		prop_object_release(pae->pdev_array);
116 		free(pae);
117 	}
118 }
119 
120 struct pdev_array_entry *
pdev_array_entry_get(int64_t generation)121 pdev_array_entry_get(int64_t generation)
122 {
123 	struct pdev_array_entry *pae;
124 	int found = 0;
125 
126 	TAILQ_FOREACH(pae, &pdev_array_list, link) {
127 		if (pae->generation == generation) {
128 			found = 1;
129 			break;
130 		}
131 	}
132 
133 	if (!found)
134 		return NULL;
135 
136 	pdev_array_entry_ref(pae);
137 	return pae;
138 }
139 
140 struct pdev_array_entry *
pdev_array_entry_get_last(void)141 pdev_array_entry_get_last(void)
142 {
143 	struct pdev_array_entry *pae;
144 
145 	pae = TAILQ_LAST(&pdev_array_list, pdev_array_list_head);
146 
147 	pdev_array_entry_ref(pae);
148 	return pae;
149 }
150