CameraService.h revision 154a320069a316491c25b716f2aeea8c51a758e8 
1/*
2**
3** Copyright (C) 2008, The Android Open Source Project
4**
5** Licensed under the Apache License, Version 2.0 (the "License");
6** you may not use this file except in compliance with the License.
7** You may obtain a copy of the License at
8**
9**     http://www.apache.org/licenses/LICENSE-2.0
10**
11** Unless required by applicable law or agreed to in writing, software
12** distributed under the License is distributed on an "AS IS" BASIS,
13** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14** See the License for the specific language governing permissions and
15** limitations under the License.
16*/
17
18#ifndef ANDROID_SERVERS_CAMERA_CAMERASERVICE_H
19#define ANDROID_SERVERS_CAMERA_CAMERASERVICE_H
20
21#include <binder/BinderService.h>
22
23#include <camera/ICameraService.h>
24#include <camera/CameraHardwareInterface.h>
25
26/* This needs to be increased if we can have more cameras */
27#define MAX_CAMERAS 2
28
29namespace android {
30
31class MemoryHeapBase;
32class MediaPlayer;
33
34class CameraService :
35    public BinderService<CameraService>,
36    public BnCameraService
37{
38    class Client;
39    friend class BinderService<CameraService>;
40public:
41    static char const* getServiceName() { return "media.camera"; }
42
43                        CameraService();
44    virtual             ~CameraService();
45
46    virtual int32_t     getNumberOfCameras();
47    virtual status_t    getCameraInfo(int cameraId,
48                                      struct CameraInfo* cameraInfo);
49    virtual sp<ICamera> connect(const sp<ICameraClient>& cameraClient, int cameraId);
50    virtual void        removeClient(const sp<ICameraClient>& cameraClient);
51    virtual sp<Client>  getClientById(int cameraId);
52
53    virtual status_t    dump(int fd, const Vector<String16>& args);
54    virtual status_t    onTransact(uint32_t code, const Parcel& data,
55                                   Parcel* reply, uint32_t flags);
56
57    enum sound_kind {
58        SOUND_SHUTTER = 0,
59        SOUND_RECORDING = 1,
60        NUM_SOUNDS
61    };
62
63    void                loadSound();
64    void                playSound(sound_kind kind);
65    void                releaseSound();
66
67private:
68    Mutex               mServiceLock;
69    wp<Client>          mClient[MAX_CAMERAS];  // protected by mServiceLock
70    int                 mNumberOfCameras;
71
72    // atomics to record whether the hardware is allocated to some client.
73    volatile int32_t    mBusy[MAX_CAMERAS];
74    void                setCameraBusy(int cameraId);
75    void                setCameraFree(int cameraId);
76
77    // sounds
78    Mutex               mSoundLock;
79    sp<MediaPlayer>     mSoundPlayer[NUM_SOUNDS];
80    int                 mSoundRef;  // reference count (release all MediaPlayer when 0)
81
82    class Client : public BnCamera
83    {
84    public:
85        // ICamera interface (see ICamera for details)
86        virtual void            disconnect();
87        virtual status_t        connect(const sp<ICameraClient>& client);
88        virtual status_t        lock();
89        virtual status_t        unlock();
90        virtual status_t        setPreviewDisplay(const sp<ISurface>& surface);
91        virtual void            setPreviewCallbackFlag(int flag);
92        virtual status_t        startPreview();
93        virtual void            stopPreview();
94        virtual bool            previewEnabled();
95        virtual status_t        startRecording();
96        virtual void            stopRecording();
97        virtual bool            recordingEnabled();
98        virtual void            releaseRecordingFrame(const sp<IMemory>& mem);
99        virtual status_t        autoFocus();
100        virtual status_t        cancelAutoFocus();
101        virtual status_t        takePicture();
102        virtual status_t        setParameters(const String8& params);
103        virtual String8         getParameters() const;
104        virtual status_t        sendCommand(int32_t cmd, int32_t arg1, int32_t arg2);
105    private:
106        friend class CameraService;
107                                Client(const sp<CameraService>& cameraService,
108                                       const sp<ICameraClient>& cameraClient,
109                                       int cameraId,
110                                       int clientPid);
111                                ~Client();
112
113        // return our camera client
114        const sp<ICameraClient>&    getCameraClient() { return mCameraClient; }
115
116        // check whether the calling process matches mClientPid.
117        status_t                checkPid() const;
118        status_t                checkPidAndHardware() const;  // also check mHardware != 0
119
120        // these are internal functions used to set up preview buffers
121        status_t                registerPreviewBuffers();
122        status_t                setOverlay();
123
124        // camera operation mode
125        enum camera_mode {
126            CAMERA_PREVIEW_MODE   = 0,  // frame automatically released
127            CAMERA_RECORDING_MODE = 1,  // frame has to be explicitly released by releaseRecordingFrame()
128        };
129        // these are internal functions used for preview/recording
130        status_t                startCameraMode(camera_mode mode);
131        status_t                startPreviewMode();
132        status_t                startRecordingMode();
133
134        // these are static callback functions
135        static void             notifyCallback(int32_t msgType, int32_t ext1, int32_t ext2, void* user);
136        static void             dataCallback(int32_t msgType, const sp<IMemory>& dataPtr, void* user);
137        static void             dataCallbackTimestamp(nsecs_t timestamp, int32_t msgType, const sp<IMemory>& dataPtr, void* user);
138        // convert client from cookie
139        static sp<Client>       getClientFromCookie(void* user);
140        // handlers for messages
141        void                    handleShutter(image_rect_type *size);
142        void                    handlePreviewData(const sp<IMemory>& mem);
143        void                    handlePostview(const sp<IMemory>& mem);
144        void                    handleRawPicture(const sp<IMemory>& mem);
145        void                    handleCompressedPicture(const sp<IMemory>& mem);
146        void                    handleGenericNotify(int32_t msgType, int32_t ext1, int32_t ext2);
147        void                    handleGenericData(int32_t msgType, const sp<IMemory>& dataPtr);
148        void                    handleGenericDataTimestamp(nsecs_t timestamp, int32_t msgType, const sp<IMemory>& dataPtr);
149
150        void                    copyFrameAndPostCopiedFrame(
151                                    const sp<ICameraClient>& client,
152                                    const sp<IMemoryHeap>& heap,
153                                    size_t offset, size_t size);
154
155        // these are initialized in the constructor.
156        sp<CameraService>               mCameraService;  // immutable after constructor
157        sp<ICameraClient>               mCameraClient;
158        int                             mCameraId;       // immutable after constructor
159        pid_t                           mClientPid;
160        sp<CameraHardwareInterface>     mHardware;       // cleared after disconnect()
161        bool                            mUseOverlay;     // immutable after constructor
162        sp<OverlayRef>                  mOverlayRef;
163        int                             mOverlayW;
164        int                             mOverlayH;
165        int                             mPreviewCallbackFlag;
166        int                             mOrientation;
167
168        // Ensures atomicity among the public methods
169        mutable Mutex                   mLock;
170        sp<ISurface>                    mSurface;
171
172        // If the user want us to return a copy of the preview frame (instead
173        // of the original one), we allocate mPreviewBuffer and reuse it if possible.
174        sp<MemoryHeapBase>              mPreviewBuffer;
175
176        // We need to avoid the deadlock when the incoming command thread and
177        // the CameraHardwareInterface callback thread both want to grab mLock.
178        // An extra flag is used to tell the callback thread that it should stop
179        // trying to deliver the callback messages if the client is not
180        // interested in it anymore. For example, if the client is calling
181        // stopPreview(), the preview frame messages do not need to be delivered
182        // anymore.
183
184        // This function takes the same parameter as the enableMsgType() and
185        // disableMsgType() functions in CameraHardwareInterface.
186        void                    enableMsgType(int32_t msgType);
187        void                    disableMsgType(int32_t msgType);
188        volatile int32_t        mMsgEnabled;
189
190        // This function keeps trying to grab mLock, or give up if the message
191        // is found to be disabled. It returns true if mLock is grabbed.
192        bool                    lockIfMessageWanted(int32_t msgType);
193    };
194};
195
196} // namespace android
197
198#endif
199