Camera2: Handle client processes dying by closing camera resources

CameraService now subscribes to binder death notifications
for each client, and disconnects the client if the death happened
without cleanly shutting down the client first.

Bug: 7258314
Change-Id: I7803836b589fd8f0dfe00f6c28a707b82012e751

1 files changed, 14 insertions, 6 deletions

diff --git a/services/camera/libcameraservice/Camera2Client.cpp b/services/camera/libcameraservice/Camera2Client.cpp
index 59ec6b6..948b59f 100644
--- a/services/camera/libcameraservice/Camera2Client.cpp
+++ b/services/camera/libcameraservice/Camera2Client.cpp
@@ -47,9 +47,10 @@ Camera2Client::Camera2Client(const sp<CameraService>& cameraService,
         const sp<ICameraClient>& cameraClient,
         int cameraId,
         int cameraFacing,
-        int clientPid):
+        int clientPid,
+        int servicePid):
         Client(cameraService, cameraClient,
-                cameraId, cameraFacing, clientPid),
+                cameraId, cameraFacing, clientPid, servicePid),
         mSharedCameraClient(cameraClient),
         mParameters(cameraId, cameraFacing)
 {
@@ -64,10 +65,10 @@ Camera2Client::Camera2Client(const sp<CameraService>& cameraService,
 
 status_t Camera2Client::checkPid(const char* checkLocation) const {
     int callingPid = getCallingPid();
-    if (callingPid == mClientPid) return NO_ERROR;
+    if (callingPid == mClientPid || callingPid == mServicePid) return NO_ERROR;
 
     ALOGE("%s: attempt to use a locked camera from a different process"
-            " (old pid %d, new pid %d)", checkLocation, mClientPid, callingPid);
+            " (old pid %d, new pid %d, servicePid %d)", checkLocation, mClientPid, callingPid, mServicePid);
     return PERMISSION_DENIED;
 }
 
@@ -138,8 +139,15 @@ Camera2Client::~Camera2Client() {
 
     mDestructionStarted = true;
 
-    SharedParameters::Lock l(mParameters);
-    if (l.mParameters.state != Parameters::DISCONNECTED) {
+    Parameters::State state;
+    // warning:
+    //   holding on to locks more than necessary may be hazardous to your health
+    {
+        SharedParameters::Lock l(mParameters);
+        state = l.mParameters.state;
+    }
+
+    if (state != Parameters::DISCONNECTED) {
         // Rewrite mClientPid to allow shutdown by CameraService
         mClientPid = getCallingPid();
         disconnect();