1 /*
2  * Copyright 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_AAUDIO_SHARED_REGION_PARCELABLE_H
18 #define ANDROID_AAUDIO_SHARED_REGION_PARCELABLE_H
19 
20 #include <stdint.h>
21 
22 #include <sys/mman.h>
23 
24 #include <aaudio/AAudio.h>
25 #include <aaudio/SharedRegion.h>
26 
27 #include "binding/SharedMemoryParcelable.h"
28 
29 using android::status_t;
30 
31 namespace aaudio {
32 
33 class SharedRegionParcelable {
34 public:
35     SharedRegionParcelable() = default;
36 
37     // Construct based on a parcelable representation.
38     explicit SharedRegionParcelable(const SharedRegion& parcelable);
39 
40     // A tuple that contains information for setting up shared memory.
41     // The information in the tuple is <shared memory index, offset, size in byte>.
42     using MemoryInfoTuple = std::tuple<int, int, int>;
43     // Enums to use as index to query from MemoryInfoTuple
44     enum {
45         MEMORY_INDEX = 0,
46         OFFSET = 1,
47         SIZE = 2,
48     };
49     void setup(MemoryInfoTuple memoryInfoTuple);
50 
51     aaudio_result_t resolve(SharedMemoryParcelable *memoryParcels, void **regionAddressPtr);
52 
53     bool isFileDescriptorSafe(SharedMemoryParcelable *memoryParcels);
54 
getSharedMemoryIndex()55     int32_t getSharedMemoryIndex() const { return mSharedMemoryIndex; }
56 
57     /**
58      * Get the memory information of this SharedRegionParcelable.
59      *
60      * If the `memoryIndexMap` is not null, it indicates the caller has a different indexing for
61      * the shared memory. In that case, the `memoryIndexMap` must contains information from the
62      * shared memory indexes used by this object to the caller's shared memory indexes.
63      *
64      * @param memoryIndexMap a pointer to a map of memory index, which map the current shared
65      *                       memory index to a new shared memory index.
66      * @return
67      */
68     MemoryInfoTuple getMemoryInfo(const std::map<int32_t, int32_t>* memoryIndexMap) const;
69 
70     void dump();
71 
72     // Extract a parcelable representation of this object.
73     SharedRegion parcelable() const;
74 
75 private:
76     int32_t mSharedMemoryIndex = -1;
77     int32_t mOffsetInBytes     = 0;
78     int32_t mSizeInBytes       = 0;
79 
80     aaudio_result_t validate() const;
81 };
82 
83 } /* namespace aaudio */
84 
85 #endif //ANDROID_AAUDIO_SHARED_REGION_PARCELABLE_H
86