1 /* Copyright (c) 2017, The Linux Foundation. All rights reserved.
2  *
3  * Redistribution and use in source and binary forms, with or without
4  * modification, are permitted provided that the following conditions are
5  * met:
6  *     * Redistributions of source code must retain the above copyright
7  *       notice, this list of conditions and the following disclaimer.
8  *     * Redistributions in binary form must reproduce the above
9  *       copyright notice, this list of conditions and the following
10  *       disclaimer in the documentation and/or other materials provided
11  *       with the distribution.
12  *     * Neither the name of The Linux Foundation, nor the names of its
13  *       contributors may be used to endorse or promote products derived
14  *       from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
17  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
23  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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25  * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
26  * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  *
28  */
29 #define LOG_TAG "DataItemsFactoryProxy"
30 
31 #include <dlfcn.h>
32 #include <DataItemId.h>
33 #include <IDataItemCore.h>
34 #include <DataItemsFactoryProxy.h>
35 #include <loc_pla.h>
36 #include <log_util.h>
37 
38 namespace loc_core
39 {
40 void* DataItemsFactoryProxy::dataItemLibHandle = NULL;
41 get_concrete_data_item_fn* DataItemsFactoryProxy::getConcreteDIFunc = NULL;
42 
createNewDataItem(DataItemId id)43 IDataItemCore* DataItemsFactoryProxy::createNewDataItem(DataItemId id)
44 {
45     IDataItemCore *mydi = nullptr;
46 
47     if (NULL != getConcreteDIFunc) {
48         mydi = (*getConcreteDIFunc)(id);
49     }
50     else {
51         // first call to this function, symbol not yet loaded
52         if (NULL == dataItemLibHandle) {
53             LOC_LOGD("Loaded library %s",DATA_ITEMS_LIB_NAME);
54             dataItemLibHandle = dlopen(DATA_ITEMS_LIB_NAME, RTLD_NOW);
55             if (NULL == dataItemLibHandle) {
56                 // dlopen failed.
57                 const char * err = dlerror();
58                 if (NULL == err)
59                 {
60                     err = "Unknown";
61                 }
62                 LOC_LOGE("%s:%d]: failed to load library %s; error=%s",
63                      __func__, __LINE__, DATA_ITEMS_LIB_NAME, err);
64             }
65         }
66 
67         // load sym - if dlopen handle is obtained and symbol is not yet obtained
68         if (NULL != dataItemLibHandle) {
69             getConcreteDIFunc = (get_concrete_data_item_fn * )
70                                     dlsym(dataItemLibHandle, DATA_ITEMS_GET_CONCRETE_DI);
71             if (NULL != getConcreteDIFunc) {
72                 LOC_LOGD("Loaded function %s : %p",DATA_ITEMS_GET_CONCRETE_DI,getConcreteDIFunc);
73                 mydi = (*getConcreteDIFunc)(id);
74             }
75             else {
76                 // dlysm failed.
77                 const char * err = dlerror();
78                 if (NULL == err)
79                 {
80                     err = "Unknown";
81                 }
82                 LOC_LOGE("%s:%d]: failed to find symbol %s; error=%s",
83                          __func__, __LINE__, DATA_ITEMS_GET_CONCRETE_DI, err);
84             }
85         }
86     }
87     return mydi;
88 }
89 
closeDataItemLibraryHandle()90 void DataItemsFactoryProxy::closeDataItemLibraryHandle()
91 {
92     if (NULL != dataItemLibHandle) {
93         dlclose(dataItemLibHandle);
94         dataItemLibHandle = NULL;
95     }
96 }
97 
98 } // namespace loc_core
99 
100 
101