cameraserver: log setTorchMode calls.

Bug: 120314037

Test: Turn torch on / off; logcat | grep 'Torch turned'
Test: Turn torch on / off; adb shell dumpsys media.camera

Change-Id: Ib98e8847f49c6977b9cba65ae0605b8abe774a15
Signed-off-by: Jayant Chowdhary <jchowdhary@google.com>

services/camera/libcameraservice/CameraService.cpp

@@ -1638,6 +1638,11 @@ Status CameraService::setTorchMode(const String16& cameraId, bool enabled,
         }
     }
 
+    int clientPid = CameraThreadState::getCallingPid();
+    const char *id_cstr = id.c_str();
+    const char *torchState = enabled ? "on" : "off";
+    ALOGI("Torch for camera id %s turned %s for client PID %d", id_cstr, torchState, clientPid);
+    logTorchEvent(id_cstr, torchState , clientPid);
     return Status::ok();
 }
 
@@ -2122,6 +2127,12 @@ void CameraService::logRejected(const char* cameraId, int clientPid,
             cameraId, clientPackage, clientPid, reason));
 }
 
+void CameraService::logTorchEvent(const char* cameraId, const char *torchState, int clientPid) {
+    // Log torch event
+    logEvent(String8::format("Torch for camera id %s turned %s for client PID %d", cameraId,
+            torchState, clientPid));
+}
+
 void CameraService::logUserSwitch(const std::set<userid_t>& oldUserIds,
         const std::set<userid_t>& newUserIds) {
     String8 newUsers = toString(newUserIds);

services/camera/libcameraservice/CameraService.h

@@ -747,6 +747,11 @@ private:
     void logRejected(const char* cameraId, int clientPid, const char* clientPackage,
             const char* reason);
 
+    /**
+     * Add an event log message when a client calls setTorchMode succesfully.
+     */
+    void logTorchEvent(const char* cameraId, const char *torchState, int clientPid);
+
     /**
      * Add an event log message that the current device user has been switched.
      */