1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0
3 *
4 * This file is provided under a dual BSD/GPLv2 license. When using or
5 * redistributing this file, you may do so under either license.
6 *
7 * GPL LICENSE SUMMARY
8 *
9 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of version 2 of the GNU General Public License as
13 * published by the Free Software Foundation.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
23 * The full GNU General Public License is included in this distribution
24 * in the file called LICENSE.GPL.
25 *
26 * BSD LICENSE
27 *
28 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
29 * All rights reserved.
30 *
31 * Redistribution and use in source and binary forms, with or without
32 * modification, are permitted provided that the following conditions
33 * are met:
34 *
35 * * Redistributions of source code must retain the above copyright
36 * notice, this list of conditions and the following disclaimer.
37 * * Redistributions in binary form must reproduce the above copyright
38 * notice, this list of conditions and the following disclaimer in
39 * the documentation and/or other materials provided with the
40 * distribution.
41 *
42 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
43 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
44 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
45 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
46 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
47 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
48 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
49 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
50 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
51 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
52 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
53 */
54
55 #include <sys/cdefs.h>
56 /**
57 * @file
58 *
59 * @brief This file contains the base subject method implementations and
60 * any constants or structures private to the base subject object.
61 * A subject is a participant in the observer design pattern. A
62 * subject represents the object being observed.
63 */
64
65 #include <dev/isci/scil/sci_types.h>
66 #include <dev/isci/scil/sci_base_subject.h>
67 #include <dev/isci/scil/sci_base_observer.h>
68
69 #if defined(SCI_LOGGING)
70
71 //******************************************************************************
72 //* P R O T E C T E D M E T H O D S
73 //******************************************************************************
74
sci_base_subject_construct(SCI_BASE_SUBJECT_T * this_subject)75 void sci_base_subject_construct(
76 SCI_BASE_SUBJECT_T *this_subject
77 )
78 {
79 this_subject->observer_list = NULL;
80 }
81
82 // ---------------------------------------------------------------------------
83
sci_base_subject_notify(SCI_BASE_SUBJECT_T * this_subject)84 void sci_base_subject_notify(
85 SCI_BASE_SUBJECT_T *this_subject
86 )
87 {
88 SCI_BASE_OBSERVER_T *this_observer = this_subject->observer_list;
89
90 while (this_observer != NULL)
91 {
92 sci_base_observer_update(this_observer, this_subject);
93
94 this_observer = this_observer->next;
95 }
96 }
97
98 // ---------------------------------------------------------------------------
99
sci_base_subject_attach_observer(SCI_BASE_SUBJECT_T * this_subject,SCI_BASE_OBSERVER_T * observer)100 void sci_base_subject_attach_observer(
101 SCI_BASE_SUBJECT_T *this_subject,
102 SCI_BASE_OBSERVER_T *observer
103 )
104 {
105 observer->next = this_subject->observer_list;
106
107 this_subject->observer_list = observer;
108 }
109
110 // ---------------------------------------------------------------------------
111
sci_base_subject_detach_observer(SCI_BASE_SUBJECT_T * this_subject,SCI_BASE_OBSERVER_T * observer)112 void sci_base_subject_detach_observer(
113 SCI_BASE_SUBJECT_T *this_subject,
114 SCI_BASE_OBSERVER_T *observer
115 )
116 {
117 SCI_BASE_OBSERVER_T *current_observer = this_subject->observer_list;
118 SCI_BASE_OBSERVER_T *previous_observer = NULL;
119
120 // Search list for the item to remove
121 while (
122 current_observer != NULL
123 && current_observer != observer
124 )
125 {
126 previous_observer = current_observer;
127 current_observer = current_observer->next;
128 }
129
130 // Was this observer in the list?
131 if (current_observer == observer)
132 {
133 if (previous_observer != NULL)
134 {
135 // Remove from middle or end of list
136 previous_observer->next = observer->next;
137 }
138 else
139 {
140 // Remove from the front of the list
141 this_subject->observer_list = observer->next;
142 }
143
144 // protect the list so people dont follow bad pointers
145 observer->next = NULL;
146 }
147 }
148
149 #endif // defined(SCI_LOGGING)
150