1 /*
2  * Copyright (C) 2016 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef ANDROID_HARDWARE_GNSS_THREADCREATIONWRAPPER_H
18 #define ANDROID_HARDWARE_GNSS_THREADCREATIONWRAPPER_H
19 
20 #include <log/log.h>
21 #include <pthread.h>
22 #include <vector>
23 
24 typedef void (*threadEntryFunc)(void* ret);
25 
26 /*
27  * This class facilitates createThreadCb methods in various GNSS interfaces to wrap
28  * pthread_create() from libc since its function signature differs from what is required by the
29  * conventional GNSS HAL. The arguments passed to pthread_create() need to be on heap and not on
30  * the stack of createThreadCb.
31  */
32 struct ThreadFuncArgs {
ThreadFuncArgsThreadFuncArgs33     ThreadFuncArgs(void (*start)(void*), void* arg) : fptr(start), args(arg) {}
34 
35     /* pointer to the function of type void()(void*) that needs to be wrapped */
36     threadEntryFunc fptr;
37     /* argument for fptr to be called with */
38     void* args;
39 };
40 
41 /*
42  * This method is simply a wrapper. It is required since pthread_create() requires an entry
43  * function pointer of type void*()(void*) and the GNSS hal requires as input a function pointer of
44  * type void()(void*).
45  */
46 void* threadFunc(void* arg);
47 
48 /*
49  * This method is called by createThreadCb with a pointer to the vector that
50  * holds the pointers to the thread arguments. The arg and start parameters are
51  * first used to create a ThreadFuncArgs object which is then saved in the
52  * listArgs parameters. The created ThreadFuncArgs object is then used to invoke
53  * threadFunc() method which in-turn invokes pthread_create.
54  */
55 pthread_t createPthread(const char* name, void (*start)(void*), void* arg,
56                         std::vector<std::unique_ptr<ThreadFuncArgs>> * listArgs);
57 
58 #endif
59