1 /*!
2  * \file       comp_attach_pt_t.h
3  * \brief      OpenCSD : Component attachment point interface class.
4  *
5  * \copyright  Copyright (c) 2015, ARM Limited. All Rights Reserved.
6  */
7 
8 /*
9  * Redistribution and use in source and binary forms, with or without modification,
10  * are permitted provided that the following conditions are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright notice,
13  * this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright notice,
16  * this list of conditions and the following disclaimer in the documentation
17  * and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the copyright holder nor the names of its contributors
20  * may be used to endorse or promote products derived from this software without
21  * specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 'AS IS' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
25  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
27  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
28  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
30  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
32  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #ifndef ARM_COMP_ATTACH_PT_T_H_INCLUDED
36 #define ARM_COMP_ATTACH_PT_T_H_INCLUDED
37 
38 #include <vector>
39 #include "opencsd/ocsd_if_types.h"
40 
41 /** @defgroup ocsd_infrastructure  OpenCSD Library : Library Component Infrastructure
42 
43     @brief Classes providing library infrastructure and auxilary functionality
44 @{*/
45 
46 #include "comp_attach_notifier_i.h"
47 
48 /*!
49  * @class componentAttachPt
50  * @brief Single component interface pointer attachment point.
51  *
52  *  This is a class template to standardise the connections between decode components.
53  *
54  *  An attachment point connects a component interface pointer to the component providing the
55  *  attachment point.
56  *
57  *  This attachment point implementation allows a single interface to be connected.
58  *
59  */
60 template <class T>
61 class componentAttachPt {
62 public:
63     componentAttachPt();    /**< Default constructor */
64     virtual ~componentAttachPt();   /**< Default destructor */
65 
66     /*!
67      * Attach an interface of type T to the attachment point.
68      *
69      * @param component : interface to attach.
70      *
71      * @return  ocsd_err_t  : OCSD_OK if successful, OCSD_ERR_ATTACH_TOO_MANY if too many connections.
72      */
73     virtual ocsd_err_t attach(T* component);
74 
75     /*!
76      * Detach component from the attachment point.
77      *
78      * @param component : Component to detach.
79      *
80      * @return virtual ocsd_err_t  : OCSD_OK if successful, OCSD_ERR_ATTACH_COMP_NOT_FOUND if no match to component.
81      */
82     virtual ocsd_err_t detach(T* component);
83 
84 
85     // detach current first if anything attached, connect supplied pointer, remain unattached if pointer 0
86     virtual ocsd_err_t replace_first(T* component);
87 
88     /*!
89      * Detach all components.
90      */
91     virtual void detach_all();
92 
93     /*!
94      * Return the current (first) attached interface pointer.
95      * Will return 0 if nothing attached or the attachment point is disabled.
96      *
97      * @return  T*  : Current Interface pointer of type T or 0.
98      */
99     virtual T* first();
100 
101     /*!
102      * Return the next attached interface.
103      * The componentAttachPt base implmentation will always return 0 as only a single attachment is possible
104      *
105      * @return  T*  :  Always returns 0.
106      */
107     virtual T* next();
108 
109     /*!
110      * Returns the number of interface pointers attached to this attachment point.
111      *
112      * @return  int  :  number of component interfaces attached.
113      */
114     virtual int num_attached();
115 
116     /*!
117      * Attach a notifier interface to the attachment point. Will call back on this interface whenever
118      * a component is attached or detached.
119      *
120      * @param *notifier : pointer to the IComponentAttachNotifier interface.
121      */
122     void set_notifier(IComponentAttachNotifier *notifier);
123 
124     /* enable state does not affect attach / detach, but can be used to filter access to interfaces */
125     const bool enabled() const; /**< return the enabled flag. */
126     void set_enabled(const bool enable);
127 
128 
129     /*!
130      * Check to see if any attachements. Will return attach state independent of enable state.
131      *
132      * @return const bool  : true if attachment.
133      */
134     const bool hasAttached() const {  return m_hasAttached; };
135 
136 
137     /*!
138      * Return both the attachment and enabled state.
139      *
140      * @return const bool  : true if both has attachment and is enabled.
141      */
142     const bool hasAttachedAndEnabled() const { return  m_hasAttached && m_enabled; };
143 
144 protected:
145     bool m_enabled; /**< Flag to indicate if the attachment point is enabled. */
146     bool m_hasAttached;      /**< Flag indicating at least one attached interface */
147     IComponentAttachNotifier *m_notifier;   /**< Optional attachement notifier interface. */
148     T *m_comp;  /**< pointer to the single attached interface */
149 };
150 
151 
152 
153 template<class T> componentAttachPt<T>::componentAttachPt()
154 {
155     m_comp = 0;
156     m_notifier = 0;
157     m_enabled = true;
158     m_hasAttached = false;
159 }
160 
161 template<class T> componentAttachPt<T>::~componentAttachPt()
162 {
163     detach_all();
164 }
165 
166 
167 template<class T> ocsd_err_t componentAttachPt<T>::attach(T* component)
168 {
169     if(m_comp != 0)
170             return OCSD_ERR_ATTACH_TOO_MANY;
171     m_comp = component;
172     if(m_notifier) m_notifier->attachNotify(1);
173     m_hasAttached = true;
174     return OCSD_OK;
175 }
176 
177 template<class T>  ocsd_err_t componentAttachPt<T>::replace_first(T* component)
178 {
179     if(m_hasAttached)
180         detach(m_comp);
181 
182     if(component == 0)
183         return OCSD_OK;
184 
185     return attach(component);
186 }
187 
188 template<class T> ocsd_err_t componentAttachPt<T>::detach(T* component)
189 {
190     if(m_comp != component)
191         return OCSD_ERR_ATTACH_COMP_NOT_FOUND;
192     m_comp = 0;
193     m_hasAttached = false;
194     if(m_notifier) m_notifier->attachNotify(0);
195     return OCSD_OK;
196 }
197 
198 template<class T> T* componentAttachPt<T>::first()
199 {
200     return (m_enabled) ? m_comp : 0;
201 }
202 
203 template<class T> T* componentAttachPt<T>::next()
204 {
205     return 0;
206 }
207 
208 template<class T> int componentAttachPt<T>::num_attached()
209 {
210     return ((m_comp != 0)  ? 1 : 0);
211 }
212 
213 template<class T> void componentAttachPt<T>::detach_all()
214 {
215     m_comp = 0;
216     m_hasAttached = false;
217     if(m_notifier) m_notifier->attachNotify(0);
218 }
219 
220 template<class T> void componentAttachPt<T>::set_notifier(IComponentAttachNotifier *notifier)
221 {
222     m_notifier = notifier;
223 }
224 
225 template<class T> const bool componentAttachPt<T>::enabled() const
226 {
227     return m_enabled;
228 }
229 
230 template<class T> void componentAttachPt<T>::set_enabled(const bool enable)
231 {
232     m_enabled = enable;
233 }
234 
235 
236 /** @}*/
237 
238 #endif // ARM_COMP_ATTACH_PT_T_H_INCLUDED
239 
240 /* End of File comp_attach_pt_t.h */
241