Add a new camera open API that allows taking the ownership.
The purpose is to let face unlock always get the camera
successfully. What happened was the camera applications may
have opened the camera in onResume under the lock screen.
This API lets face unlock take the camera from the camera
application. A new permission will be added, so other
applicatoins won't be able to take the camera from the face
unlock.
bug:5584464
Change-Id: Ib3d9dcbc2161815b68db42327dc01148453704c6
diff --git a/services/camera/libcameraservice/CameraService.cpp b/services/camera/libcameraservice/CameraService.cpp
index adf1d49..22836e3 100644
--- a/services/camera/libcameraservice/CameraService.cpp
+++ b/services/camera/libcameraservice/CameraService.cpp
@@ -21,6 +21,7 @@
#include <stdio.h>
#include <sys/types.h>
#include <pthread.h>
+#include <time.h>
#include <binder/IPCThreadState.h>
#include <binder/IServiceManager.h>
@@ -33,6 +34,7 @@
#include <hardware/hardware.h>
#include <media/AudioSystem.h>
#include <media/mediaplayer.h>
+#include <utils/Condition.h>
#include <utils/Errors.h>
#include <utils/Log.h>
#include <utils/String16.h>
@@ -42,6 +44,8 @@
namespace android {
+#define WAIT_RELEASE_TIMEOUT 250 // 250ms
+
// ----------------------------------------------------------------------------
// Logging support -- this is for debugging only
// Use "adb shell dumpsys media.camera -v 1" to change it.
@@ -64,6 +68,13 @@
return IPCThreadState::self()->getCallingUid();
}
+static long long getTimeInMs() {
+ struct timeval t;
+ t.tv_sec = t.tv_usec = 0;
+ gettimeofday(&t, NULL);
+ return t.tv_sec * 1000LL + t.tv_usec / 1000;
+}
+
// ----------------------------------------------------------------------------
// This is ugly and only safe if we never re-create the CameraService, but
@@ -131,7 +142,7 @@
}
sp<ICamera> CameraService::connect(
- const sp<ICameraClient>& cameraClient, int cameraId) {
+ const sp<ICameraClient>& cameraClient, int cameraId, bool force, bool keep) {
int callingPid = getCallingPid();
sp<CameraHardwareInterface> hardware = NULL;
@@ -157,27 +168,73 @@
return NULL;
}
- Mutex::Autolock lock(mServiceLock);
- if (mClient[cameraId] != 0) {
- client = mClient[cameraId].promote();
- if (client != 0) {
- if (cameraClient->asBinder() == client->getCameraClient()->asBinder()) {
- LOG1("CameraService::connect X (pid %d) (the same client)",
- callingPid);
- return client;
- } else {
- ALOGW("CameraService::connect X (pid %d) rejected (existing client).",
- callingPid);
- return NULL;
- }
- }
- mClient[cameraId].clear();
+ if (keep && !checkCallingPermission(String16("android.permission.KEEP_CAMERA"))) {
+ ALOGE("connect X (pid %d) rejected (no KEEP_CAMERA permission).", callingPid);
+ return NULL;
}
- if (mBusy[cameraId]) {
- ALOGW("CameraService::connect X (pid %d) rejected"
- " (camera %d is still busy).", callingPid, cameraId);
- return NULL;
+ Mutex::Autolock lock(mServiceLock);
+ // Check if there is an existing client.
+ client = mClient[cameraId].promote();
+ if (client != 0 &&
+ cameraClient->asBinder() == client->getCameraClient()->asBinder()) {
+ LOG1("connect X (pid %d) (the same client)", callingPid);
+ return client;
+ }
+
+ if (!force) {
+ if (mClient[cameraId].promote() != 0) {
+ ALOGW("connect X (pid %d) rejected (existing client).", callingPid);
+ return NULL;
+ }
+ mClient[cameraId].clear();
+ if (mBusy[cameraId]) {
+ ALOGW("connect X (pid %d) rejected (camera %d is still busy).",
+ callingPid, cameraId);
+ return NULL;
+ }
+ } else { // force == true
+ int i = 0;
+ long long start_time = getTimeInMs();
+ while (i < mNumberOfCameras) {
+ if (getTimeInMs() - start_time >= 3000LL) {
+ ALOGE("connect X (pid %d) rejected (timeout 3s)", callingPid);
+ return NULL;
+ }
+
+ client = mClient[i].promote();
+ if (client != 0) {
+ if (client->keep()) {
+ ALOGW("connect X (pid %d) rejected (existing client wants to keeps the camera)",
+ callingPid);
+ return NULL;
+ } else {
+ ALOGW("New client (pid %d, id=%d). Disconnect the existing client (id=%d).",
+ callingPid, cameraId, i);
+ // Do not hold mServiceLock because disconnect will try to get it.
+ mServiceLock.unlock();
+ client->notifyCallback(CAMERA_MSG_ERROR, CAMERA_ERROR_RELEASED, 0, &i);
+ client->waitRelease(WAIT_RELEASE_TIMEOUT);
+ client->disconnectInternal(false);
+ mServiceLock.lock();
+ // Restart from the first client because a new client may have connected
+ // when mServiceLock is unlocked.
+ i = 0;
+ continue;
+ }
+ }
+
+ if (mBusy[i]) {
+ // Give the client a chance to release the hardware.
+ mServiceLock.unlock();
+ usleep(10 * 1000);
+ mServiceLock.lock();
+ i = 0; // Restart from the first client
+ continue;
+ }
+
+ i++;
+ }
}
struct camera_info info;
@@ -195,9 +252,15 @@
return NULL;
}
- client = new Client(this, cameraClient, hardware, cameraId, info.facing, callingPid);
+ client = new Client(this, cameraClient, hardware, cameraId, info.facing,
+ callingPid, keep);
+ // We need to clear the hardware here. After the destructor of mServiceLock
+ // finishes, a new client may connect and disconnect this client. If this
+ // reference is not cleared, the destructor of CameraHardwareInterface
+ // cannot run. The new client will not be able to connect.
+ hardware.clear();
mClient[cameraId] = client;
- LOG1("CameraService::connect X");
+ LOG1("CameraService::connect X (id %d)", cameraId);
return client;
}
@@ -331,9 +394,9 @@
CameraService::Client::Client(const sp<CameraService>& cameraService,
const sp<ICameraClient>& cameraClient,
const sp<CameraHardwareInterface>& hardware,
- int cameraId, int cameraFacing, int clientPid) {
+ int cameraId, int cameraFacing, int clientPid, bool keep) {
int callingPid = getCallingPid();
- LOG1("Client::Client E (pid %d)", callingPid);
+ LOG1("Client::Client E (pid %d, id %d)", callingPid, cameraId);
mCameraService = cameraService;
mCameraClient = cameraClient;
@@ -341,6 +404,7 @@
mCameraId = cameraId;
mCameraFacing = cameraFacing;
mClientPid = clientPid;
+ mKeep = keep;
mMsgEnabled = 0;
mSurface = 0;
mPreviewWindow = 0;
@@ -359,7 +423,7 @@
mPlayShutterSound = true;
cameraService->setCameraBusy(cameraId);
cameraService->loadSound();
- LOG1("Client::Client X (pid %d)", callingPid);
+ LOG1("Client::Client X (pid %d, id %d)", callingPid, cameraId);
}
// tear down the client
@@ -468,18 +532,24 @@
}
void CameraService::Client::disconnect() {
+ disconnectInternal(true);
+}
+
+void CameraService::Client::disconnectInternal(bool needCheckPid) {
int callingPid = getCallingPid();
- LOG1("disconnect E (pid %d)", callingPid);
+ LOG1("disconnectInternal E (pid %d)", callingPid);
Mutex::Autolock lock(mLock);
- if (checkPid() != NO_ERROR) {
- ALOGW("different client - don't disconnect");
- return;
- }
+ if (needCheckPid) {
+ if (checkPid() != NO_ERROR) {
+ ALOGW("different client - don't disconnect");
+ return;
+ }
- if (mClientPid <= 0) {
- LOG1("camera is unlocked (mClientPid = %d), don't tear down hardware", mClientPid);
- return;
+ if (mClientPid <= 0) {
+ LOG1("camera is unlocked (mClientPid = %d), don't tear down hardware", mClientPid);
+ return;
+ }
}
// Make sure disconnect() is done once and once only, whether it is called
@@ -506,8 +576,16 @@
mCameraService->removeClient(mCameraClient);
mCameraService->setCameraFree(mCameraId);
+ mReleaseCondition.signal();
- LOG1("disconnect X (pid %d)", callingPid);
+ LOG1("disconnectInternal X (pid %d)", callingPid);
+}
+
+void CameraService::Client::waitRelease(int ms) {
+ Mutex::Autolock lock(mLock);
+ if (mHardware != 0) {
+ mReleaseCondition.waitRelative(mLock, ms * 1000000);
+ }
}
// ----------------------------------------------------------------------------
@@ -874,6 +952,9 @@
return OK;
} else if (cmd == CAMERA_CMD_PLAY_RECORDING_SOUND) {
mCameraService->playSound(SOUND_RECORDING);
+ } else if (cmd == CAMERA_CMD_PING) {
+ // If mHardware is 0, checkPidAndHardware will return error.
+ return OK;
}
return mHardware->sendCommand(cmd, arg1, arg2);
@@ -1217,6 +1298,10 @@
return -1;
}
+// Whether the client wants to keep the camera from taking
+bool CameraService::Client::keep() const {
+ return mKeep;
+}
// ----------------------------------------------------------------------------
diff --git a/services/camera/libcameraservice/CameraService.h b/services/camera/libcameraservice/CameraService.h
index bad41f5..457c79b 100644
--- a/services/camera/libcameraservice/CameraService.h
+++ b/services/camera/libcameraservice/CameraService.h
@@ -46,7 +46,8 @@
virtual int32_t getNumberOfCameras();
virtual status_t getCameraInfo(int cameraId,
struct CameraInfo* cameraInfo);
- virtual sp<ICamera> connect(const sp<ICameraClient>& cameraClient, int cameraId);
+ virtual sp<ICamera> connect(const sp<ICameraClient>& cameraClient, int cameraId,
+ bool force, bool keep);
virtual void removeClient(const sp<ICameraClient>& cameraClient);
virtual sp<Client> getClientById(int cameraId);
@@ -114,7 +115,8 @@
const sp<CameraHardwareInterface>& hardware,
int cameraId,
int cameraFacing,
- int clientPid);
+ int clientPid,
+ bool keep);
~Client();
// return our camera client
@@ -172,12 +174,19 @@
const sp<IBinder>& binder,
const sp<ANativeWindow>& window);
+ void disconnectInternal(bool needCheckPid);
+ bool keep() const;
+ void waitRelease(int ms);
+
+
// these are initialized in the constructor.
sp<CameraService> mCameraService; // immutable after constructor
sp<ICameraClient> mCameraClient;
int mCameraId; // immutable after constructor
int mCameraFacing; // immutable after constructor
pid_t mClientPid;
+ // Client wants to keep the camera from taking by other clients.
+ bool mKeep;
sp<CameraHardwareInterface> mHardware; // cleared after disconnect()
int mPreviewCallbackFlag;
int mOrientation; // Current display orientation
@@ -185,6 +194,8 @@
// Ensures atomicity among the public methods
mutable Mutex mLock;
+ // This will get notified when the hardware is released.
+ Condition mReleaseCondition;
// This is a binder of Surface or SurfaceTexture.
sp<IBinder> mSurface;
sp<ANativeWindow> mPreviewWindow;