class NSCFNumber autoreleased with no pool in place - just leaking - c++

I am new to C++ and have just started to work on a project using threading.
Currently my project involves the OpenGL and OpenCV libraries, and in the process of coding I encountered the following error :
Current language: auto; currently c++
2009-12-21 14:54:49.438 3DTestApp[3210:7803] *** _NSAutoreleaseNoPool(): Object 0x10ebe0 of class NSCFNumber autoreleased with no pool in place - just leaking
Stack: (0x91edff4f 0x91dec432 0x941ad394 0x94282218 0x94281b32 0x94528023 0x942813ef 0x94280dc6 0x94489ef4 0x944882ab 0x9350e13d 0x9350d57b 0x9350d3e0 0x93529e29 0x93529bce 0x935292a8 0x935290e4 0x5743e2)
kill
quit
I put breakpoints and realised the error occurred only after the following line was executed:
cvShowImage("Motion Tracker", detectionMotionScreen); (this code was in a thread with infinite loop)
I have googled around and realised that this error only occurred in Objective C, and I found no results related to C++.
As such, I would wish to ask if anyone has any idea why has this occurred, and is there anyway to fix it?
edit : I have tried adding the framework Foundation to use NSAutoreleasePool, however upon compiliing it generates alot of errors in my codes with regards to the syntax, when actually there were none.

Apple doesn't have any public interfaces written in C++ outside of IOKit, so you're not going to find any. The procedural C documentation on CoreFoundation memory management is here.
If you want more specific help then you're going to need to describe what it is you're doing a lot more thoroughly.

Related

(ROS) Failed to create global planner

My setup is: ROS melodic, Ubuntu: 18.04
I want simulate turtlebot3 moving with my own global planner and have been following this tutorial to get started: http://wiki.ros.org/navigation/Tutorials/Writing%20A%20Global%20Path%20Planner%20As%20Plugin%20in%20ROS#Running_the_Plugin_on_the_Turtlebot. The tutorial seem to be made for ROS hydro, but as it was the best source of guidance I could find I hoped it would work.
The error I'm having is:
Failed to create the global_planner/GlobalPlanner planner, are you sure it is properly registered and that the containing library is built? Exception: MultiLibraryClassLoader: Could not create object of class type global_planner::GlobalPlanner as no factory exists for it. Make sure that the library exists and was explicitly loaded through MultiLibraryClassLoader::loadLibrary()
To my knowledge I've followed the tutorial as much as possible with a only a few things done differently because I wanted to test it, couldn't do as the tutorial asked, or because I thought it wouldn't impact the results. What I have done differently is:
I use the carrot_planner.h and carrot_planner.cpp files in the tutorial section 1 to test that it works before trying with my own code to avoid confusion about where possible errors come from. It's not 'different' from the tutorial to my knowledge, but figured I'd mention it. They are placed in catkin_ws/src/carrot_planner/src/global_planner/
The ros package I'm working from is in catkin_ws/src and is called the carrot_planner. In the tutorial step 1.3 I use add_library(global_planner_lib src/global_planner/carrot_planner.cpp). Would not imagine it affects the results either.
In section 3 of the tutorial it mentions that 'First, you need to copy the package that contains your global planner (in our case global_planner) into the catkin workspace of your Turtlebot (e.g. catkin_ws).' Since my package was already in catkin_ws/src/ I haven't moved it since I guess I didn't need to.
I've altered the 'move_base.launch' file in '/opt/ros/melodic/share/turtlebot3_navigation/launch/' instead of the 'move_base.launch.xml' in '/opt/ros/hydro/share/turtlebot_navigation/launch/includes/' as there doesn't seem to be a destination '...turtlebot3_navigation/launch/includes/'. There are files in launch, but no includes folder. Maybe that a difference from Hydro to Melodic, I don't know. There may be a whole lot of things that need to be done differently from the tutorial when using Melodic, or with turtlebot3, but I don't know.
I haven't made my own launch file for bringup of the turtlebot, but have instead followed this tutorial (https://emanual.robotis.com/docs/en/platform/turtlebot3/nav_simulation/) to guide me with turtlebot3. After finishing this step in the global planner tutorial 'Save and close the move_base.launch.xml. Note that the name of the planner is global_planner/GlobalPlanner the same specified in global_planner_plugin.xml. Now, you are ready to use your new planner' I tested whether it worked by running: 'roslaunch turtlebot3_gazebo turtlebot3_world.launch' and then I tried running: 'roslaunch turtlebot3_navigation turtlebot3_navigation.launch map_file:=$HOME/map.yaml' which led to the error I showed above. I have created the map-yaml, so there's no misunderstanding whether that's missing.
I would be very glad for any help, thank you ^^
Edit: My system only had 'navfn' on it, not 'global_planner' or 'carrot_planner', if that makes a difference.
After looking over the code I found a solution. It doesn't make everything work perfectly yet, but seems to solve the immediate problem.
The problem was that in my 'global_planner_plugin.xml' I just used the code provided in the tutorial:
<library path="lib/libglobal_planner_lib">
<class name="global_planner/GlobalPlanner" type="global_planner::GlobalPlanner" base_class_type="nav_core::BaseGlobalPlanner">
<description>This is a global planner plugin by iroboapp project.</description>
</class>
</library>
But in the carrot_planner.cpp file it says:
PLUGINLIB_EXPORT_CLASS(carrot_planner::CarrotPlanner, nav_core::BaseGlobalPlanner)
Changing type="global_planner::GlobalPlanner to type="carrot_planner::CarrotPlanner and then launching turtlebot3 doesn't give the same error anymore.

Alternative of CreateVideoSource() in webrtc

Hi all I had seen one webrtc old source code which has this method called CreateVideoSource() for adding streams after an CreateAudioTrack() call.
rtc::scoped_refptr<webrtc::VideoTrackSourceInterface> video_source =
peer_connection_factory_->CreateVideoSource(std::unique_ptr<cricket::VideoCapturer>(
media_source->GetVideoCapturer()),
NULL);
What's happening is whenever I try to build it gives an error for the above CreateVideoSource() that it is undefined. And the reason behind that is the latest webrtc-checkout has deprecated this.
So my question is, I wanted to know the alternative which they have introduced after deprecating this method. So can anyone tell me what the alternate approach is.
Okay, Finally I was able to come up with an alternative(i.e the current implementation of libwebrtc) after looking into bundle examples and tests.
Line 71 is a good point to start

Google Play Services C++ / Run UI on second activity using IntentHandler

I am developing a mobile game using Cocos2D-x engine for android platform and i want to integrate GPGS on it.
I achieved to show leaderboards, but there is a little annoying problem. When leaderboard is visible, if i go background and then come back to app, the gamescene goes to black. I think opengl context being released and doesnt restore again. In my opinion running leaderboard on same activity causes this, the game engine cant understand whats happening there. Whatever, because of this I want to run leaderboard (and also all GPGS things) on a new activity using intent.
Google likes "Providing"
In the reference documents of Google Play Game Services C++ SDK, there is a few unclear/fuzzy explanation about using SetOptionalIntentHandlerForUI method.
"Provide a function that can start a provided UI intent at any point, using startActivityForResult."
What is the mean of "Providing"? What is a provided Intent? How will I use startActivityForResult method? Unfortunately, "using" and "providing methods" are not clear expressions for coding. There is no sample about
using this method in the documents of GPGS for C++. Eventually,
Google's document is so poor and
there is no useful information on the internet. If someone from Google helps me, I will be so happy.
As i understand, I wrote the code like this. But it gives error when starting.
AppActivity.java
public void runGPGSActivity(Intent i) {
startActivityForResult(i,100);
}
AndroidPlatformConfiguration.h (From C++ gpg lib)
typedef std::function<void(jobject)> IntentHandler;
AndroidPlatformConfiguration &SetOptionalIntentHandlerForUI(
IntentHandler intent_handler);
main.cpp (JNI binding, the working code, GPGS runs on same activity )
gpg::AndroidPlatformConfiguration platform_configuration;
platform_configuration.SetActivity(activity);
StateManager::InitServices( ...
main.cpp (JNI binding, GPGS must be run on new activity )
gpg::AndroidPlatformConfiguration platform_configuration;
jclass activityClass = env->FindClass("org/cocos2dx/cpp/AppActivity");
jmethodID jIntentHandlerMethodID = env->GetMethodID(activityClass,"runGPGSActivity","(Landorid/content/Intent;)V");
jobject jIntentHandler = env->NewObject(activityClass, jIntentHandlerMethodID);
gpg::AndroidPlatformConfiguration::IntentHandler mIntentHandler; /*= [](jobject mjIntentHandler){};*/
std::function<void(jobject)> intentHandler = std::bind(mIntentHandler,jIntentHandler);
platform_configuration.SetOptionalIntentHandlerForUI(intentHandler);
platform_configuration.SetActivity(activity);
StateManager::InitServices(
There is no build error, but the application crashes when launching.
03-24 14:12:24.301: A/libc(21352): Fatal signal 6 (SIGABRT) at
0x00005368 (code=-6), thread 21352 (main)
And some links about this issue:
IntentHandler reference
StartActivityForResult reference
/// Thank you in advance. ///
...Yeah I solved the problem, but didn't use IntentHandler method.
I was using this code in my app, to show weekly leaderboard data.
gameServices->Leaderboards().ShowUIBlocking(leaderboardId,gpg::LeaderboardTimeSpan::WEEKLY);
But return value is not void, it is UIStatus (whatever it is)
I've reverted back to this code, app is not going to black screen now. This method returns void, I think I have to catch some callbacks when using ShowUIBlocking method, with that UIStatus thing.
gameServices->Leaderboards().ShowUI(leaderboardId);
But now, I can't benefit from timespan feature of leaderboards.
I am going to research how it can be used. There is no problem for now. But, documentation of SetOptionalIntentHandlerForUI must be written more explicit, for programmers who want to use it.

OpenCV. FisherFace "model->predict"

First time question here, tx in advance.
I am trying to use code from opencv tutorial that use the fisherface algorithim.
I am able to create the fisherface model and train it,detect faces but fail on the recognition part model->predict.
I am also pretty new to C++ and trying to debug this problem myself but I guess I still need help here.
Jumping in at line model->predict(face_im)
I get to the following line of code in operations.hpp and fail immediately without any description of the error.
template<typename _Tp> inline _Tp* Ptr<_Tp>::operator -> () { return obj; }
executing this line jumps back out to the main and breaks with error
Access violation reading location 0x00000019.
agh, I hope this is not to vague but how can i analyze my problem here?
Again tx in advance and if more info is needed ..sure thing
Et
I've come to a conclusion; it was a scoping problem. By moving the declaration out of main, I was able to get it to work fine.
I guess it was very vague. It's still a bit unclear to me, but I suppose I need to brush up on my C++.

Nodejs C++ event emitter. add-on error. Non-function in MakeCallback. method = emit Abort trap: 6

I'm creating a C++ level event emitter addon for node.js. I'm getting this C++ error when including the add-on in a node.js project.
Non-function in MakeCallback. method = emit Abort trap: 6
I found this Gist with a simplified example of the same behavior:
https://gist.github.com/jedi4ever/4250746
Hoping for some general insight into why this might be caused or what this error means.
If I understand what you're trying to do correctly, you have a couple of problems in your keylogger.js file;
util.inherits(new keylogger, events.EventEmitter);
exports = keylogger;
You're trying to extend an instance, and your export statement is a bit off. This should work better to export keylogger as an instance which the test file seems to expect;
util.inherits(keylogger, events.EventEmitter);
exports.keylogger = new keylogger();