1 /*
2  * Copyright (C) 2015 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 _ACAMERA_MANAGER_H
18 #define _ACAMERA_MANAGER_H
19 
20 #include "NdkCameraManager.h"
21 
22 #include <android/hardware/ICameraService.h>
23 #include <android/hardware/BnCameraServiceListener.h>
24 #include <camera/CameraMetadata.h>
25 #include <binder/IServiceManager.h>
26 #include <utils/StrongPointer.h>
27 #include <utils/Mutex.h>
28 
29 #include <media/stagefright/foundation/ALooper.h>
30 #include <media/stagefright/foundation/AHandler.h>
31 #include <media/stagefright/foundation/AMessage.h>
32 
33 #include <set>
34 #include <map>
35 
36 namespace android {
37 
38 /**
39  * Per-process singleton instance of CameraManger. Shared by all ACameraManager
40  * instances. Created when first ACameraManager is created and destroyed when
41  * all ACameraManager instances are deleted.
42  *
43  * TODO: maybe CameraManagerGlobal is better sutied in libcameraclient?
44  */
45 class CameraManagerGlobal final : public RefBase {
46   public:
47     static CameraManagerGlobal& getInstance();
48     sp<hardware::ICameraService> getCameraService();
49 
50     void registerAvailabilityCallback(
51             const ACameraManager_AvailabilityCallbacks *callback);
52     void unregisterAvailabilityCallback(
53             const ACameraManager_AvailabilityCallbacks *callback);
54 
55   private:
56     sp<hardware::ICameraService> mCameraService;
57     const int          kCameraServicePollDelay = 500000; // 0.5s
58     const char*        kCameraServiceName      = "media.camera";
59     Mutex              mLock;
60 
61     class DeathNotifier : public IBinder::DeathRecipient {
62       public:
DeathNotifier(CameraManagerGlobal * cm)63         DeathNotifier(CameraManagerGlobal* cm) : mCameraManager(cm) {}
64       protected:
65         // IBinder::DeathRecipient implementation
66         virtual void binderDied(const wp<IBinder>& who);
67       private:
68         const wp<CameraManagerGlobal> mCameraManager;
69     };
70     sp<DeathNotifier> mDeathNotifier;
71 
72     class CameraServiceListener final : public hardware::BnCameraServiceListener {
73       public:
CameraServiceListener(CameraManagerGlobal * cm)74         CameraServiceListener(CameraManagerGlobal* cm) : mCameraManager(cm) {}
75         virtual binder::Status onStatusChanged(int32_t status, int32_t cameraId);
76 
77         // Torch API not implemented yet
onTorchStatusChanged(int32_t,const String16 &)78         virtual binder::Status onTorchStatusChanged(int32_t, const String16&) {
79             return binder::Status::ok();
80         }
81 
82       private:
83         const wp<CameraManagerGlobal> mCameraManager;
84     };
85     sp<CameraServiceListener> mCameraServiceListener;
86 
87     // Wrapper of ACameraManager_AvailabilityCallbacks so we can store it in std::set
88     struct Callback {
CallbackCallback89         Callback(const ACameraManager_AvailabilityCallbacks *callback) :
90             mAvailable(callback->onCameraAvailable),
91             mUnavailable(callback->onCameraUnavailable),
92             mContext(callback->context) {}
93 
94         bool operator == (const Callback& other) const {
95             return (mAvailable == other.mAvailable &&
96                     mUnavailable == other.mUnavailable &&
97                     mContext == other.mContext);
98         }
99         bool operator != (const Callback& other) const {
100             return !(*this == other);
101         }
102         bool operator < (const Callback& other) const {
103             if (*this == other) return false;
104             if (mContext != other.mContext) return mContext < other.mContext;
105             if (mAvailable != other.mAvailable) return mAvailable < other.mAvailable;
106             return mUnavailable < other.mUnavailable;
107         }
108         bool operator > (const Callback& other) const {
109             return (*this != other && !(*this < other));
110         }
111         ACameraManager_AvailabilityCallback mAvailable;
112         ACameraManager_AvailabilityCallback mUnavailable;
113         void*                               mContext;
114     };
115     std::set<Callback> mCallbacks;
116 
117     // definition of handler and message
118     enum {
119         kWhatSendSingleCallback
120     };
121     static const char* kCameraIdKey;
122     static const char* kCallbackFpKey;
123     static const char* kContextKey;
124     class CallbackHandler : public AHandler {
125       public:
CallbackHandler()126         CallbackHandler() {}
127         void onMessageReceived(const sp<AMessage> &msg) override;
128       private:
129         inline void sendSingleCallback(
130                 int32_t cameraId, void* context,
131                 ACameraManager_AvailabilityCallback cb) const;
132     };
133     sp<CallbackHandler> mHandler;
134     sp<ALooper>         mCbLooper; // Looper thread where callbacks actually happen on
135 
136     void onStatusChanged(int32_t status, int32_t cameraId);
137     void onStatusChangedLocked(int32_t status, int32_t cameraId);
138     // Utils for status
139     static bool validStatus(int32_t status);
140     static bool isStatusAvailable(int32_t status);
141 
142     // Map camera_id -> status
143     std::map<int32_t, int32_t> mDeviceStatusMap;
144 
145     // For the singleton instance
146     static Mutex sLock;
147     static CameraManagerGlobal* sInstance;
CameraManagerGlobal()148     CameraManagerGlobal() {};
149     ~CameraManagerGlobal();
150 };
151 
152 } // namespace android;
153 
154 /**
155  * ACameraManager opaque struct definition
156  * Leave outside of android namespace because it's NDK struct
157  */
158 struct ACameraManager {
ACameraManagerACameraManager159     ACameraManager() :
160             mCachedCameraIdList({kCameraIdListNotInit, nullptr}),
161             mGlobalManager(&(android::CameraManagerGlobal::getInstance())) {}
162     ~ACameraManager();
163     camera_status_t getCameraIdList(ACameraIdList** cameraIdList);
164     static void     deleteCameraIdList(ACameraIdList* cameraIdList);
165 
166     camera_status_t getCameraCharacteristics(
167             const char *cameraId, ACameraMetadata **characteristics);
168     camera_status_t openCamera(const char* cameraId,
169                                ACameraDevice_StateCallbacks* callback,
170                                /*out*/ACameraDevice** device);
171 
172   private:
173     camera_status_t getOrCreateCameraIdListLocked(ACameraIdList** cameraIdList);
174 
175     enum {
176         kCameraIdListNotInit = -1
177     };
178     android::Mutex         mLock;
179     std::set<int> mCameraIds;          // Init by getOrCreateCameraIdListLocked
180     ACameraIdList mCachedCameraIdList; // Init by getOrCreateCameraIdListLocked
181     android::sp<android::CameraManagerGlobal> mGlobalManager;
182 };
183 
184 #endif //_ACAMERA_MANAGER_H
185