ACameraManager.h revision d19d994770a04f02c204affd29985c5aeaa58baa 
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
36namespace 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 */
45class 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:
63        explicit 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:
74        explicit CameraServiceListener(CameraManagerGlobal* cm) : mCameraManager(cm) {}
75        virtual binder::Status onStatusChanged(int32_t status, int32_t cameraId);
76
77        // Torch API not implemented yet
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 {
89        explicit 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:
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;
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 */
158struct ACameraManager {
159    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