CameraService.h revision b5ca4618a722a21f084fe8bfc1c2992749ccd3f0 
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    // Used by Client objects to extract the ISurface from a Surface object.
83    // This is used because making Client a friend class of Surface would
84    // require including this header in Surface.h since Client is a nested
85    // class.
86    static sp<ISurface> getISurface(const sp<Surface>& surface);
87
88    class Client : public BnCamera
89    {
90    public:
91        // ICamera interface (see ICamera for details)
92        virtual void            disconnect();
93        virtual status_t        connect(const sp<ICameraClient>& client);
94        virtual status_t        lock();
95        virtual status_t        unlock();
96        virtual status_t        setPreviewDisplay(const sp<Surface>& surface);
97        virtual void            setPreviewCallbackFlag(int flag);
98        virtual status_t        startPreview();
99        virtual void            stopPreview();
100        virtual bool            previewEnabled();
101        virtual status_t        startRecording();
102        virtual void            stopRecording();
103        virtual bool            recordingEnabled();
104        virtual void            releaseRecordingFrame(const sp<IMemory>& mem);
105        virtual status_t        autoFocus();
106        virtual status_t        cancelAutoFocus();
107        virtual status_t        takePicture();
108        virtual status_t        setParameters(const String8& params);
109        virtual String8         getParameters() const;
110        virtual status_t        sendCommand(int32_t cmd, int32_t arg1, int32_t arg2);
111    private:
112        friend class CameraService;
113                                Client(const sp<CameraService>& cameraService,
114                                       const sp<ICameraClient>& cameraClient,
115                                       const sp<CameraHardwareInterface>& hardware,
116                                       int cameraId,
117                                       int clientPid);
118                                ~Client();
119
120        // return our camera client
121        const sp<ICameraClient>&    getCameraClient() { return mCameraClient; }
122
123        // check whether the calling process matches mClientPid.
124        status_t                checkPid() const;
125        status_t                checkPidAndHardware() const;  // also check mHardware != 0
126
127        // these are internal functions used to set up preview buffers
128        status_t                registerPreviewBuffers();
129        status_t                setOverlay();
130
131        // camera operation mode
132        enum camera_mode {
133            CAMERA_PREVIEW_MODE   = 0,  // frame automatically released
134            CAMERA_RECORDING_MODE = 1,  // frame has to be explicitly released by releaseRecordingFrame()
135        };
136        // these are internal functions used for preview/recording
137        status_t                startCameraMode(camera_mode mode);
138        status_t                startPreviewMode();
139        status_t                startRecordingMode();
140
141        // internal function used by sendCommand to enable/disable shutter sound.
142        status_t                enableShutterSound(bool enable);
143
144        // these are static callback functions
145        static void             notifyCallback(int32_t msgType, int32_t ext1, int32_t ext2, void* user);
146        static void             dataCallback(int32_t msgType, const sp<IMemory>& dataPtr, void* user);
147        static void             dataCallbackTimestamp(nsecs_t timestamp, int32_t msgType, const sp<IMemory>& dataPtr, void* user);
148        // convert client from cookie
149        static sp<Client>       getClientFromCookie(void* user);
150        // handlers for messages
151        void                    handleShutter(image_rect_type *size);
152        void                    handlePreviewData(const sp<IMemory>& mem);
153        void                    handlePostview(const sp<IMemory>& mem);
154        void                    handleRawPicture(const sp<IMemory>& mem);
155        void                    handleCompressedPicture(const sp<IMemory>& mem);
156        void                    handleGenericNotify(int32_t msgType, int32_t ext1, int32_t ext2);
157        void                    handleGenericData(int32_t msgType, const sp<IMemory>& dataPtr);
158        void                    handleGenericDataTimestamp(nsecs_t timestamp, int32_t msgType, const sp<IMemory>& dataPtr);
159
160        void                    copyFrameAndPostCopiedFrame(
161                                    const sp<ICameraClient>& client,
162                                    const sp<IMemoryHeap>& heap,
163                                    size_t offset, size_t size);
164
165        // these are initialized in the constructor.
166        sp<CameraService>               mCameraService;  // immutable after constructor
167        sp<ICameraClient>               mCameraClient;
168        int                             mCameraId;       // immutable after constructor
169        pid_t                           mClientPid;
170        sp<CameraHardwareInterface>     mHardware;       // cleared after disconnect()
171        bool                            mUseOverlay;     // immutable after constructor
172        sp<OverlayRef>                  mOverlayRef;
173        int                             mOverlayW;
174        int                             mOverlayH;
175        int                             mPreviewCallbackFlag;
176        int                             mOrientation;
177        bool                            mPlayShutterSound;
178
179        // Ensures atomicity among the public methods
180        mutable Mutex                   mLock;
181        sp<ISurface>                    mSurface;
182        sp<ANativeWindow>               mPreviewWindow;
183
184        // If the user want us to return a copy of the preview frame (instead
185        // of the original one), we allocate mPreviewBuffer and reuse it if possible.
186        sp<MemoryHeapBase>              mPreviewBuffer;
187
188        // We need to avoid the deadlock when the incoming command thread and
189        // the CameraHardwareInterface callback thread both want to grab mLock.
190        // An extra flag is used to tell the callback thread that it should stop
191        // trying to deliver the callback messages if the client is not
192        // interested in it anymore. For example, if the client is calling
193        // stopPreview(), the preview frame messages do not need to be delivered
194        // anymore.
195
196        // This function takes the same parameter as the enableMsgType() and
197        // disableMsgType() functions in CameraHardwareInterface.
198        void                    enableMsgType(int32_t msgType);
199        void                    disableMsgType(int32_t msgType);
200        volatile int32_t        mMsgEnabled;
201
202        // This function keeps trying to grab mLock, or give up if the message
203        // is found to be disabled. It returns true if mLock is grabbed.
204        bool                    lockIfMessageWanted(int32_t msgType);
205    };
206};
207
208} // namespace android
209
210#endif
211