Database Users

What code language is this?????

I found this code posted on another thread, but was wondering... What language is this? And what software do I need to compile it? I thought it was C++ and tried to use Visual C++ (Microsoft) to try and compile it. I saved the file as a .cpp and tried to compile it from the command prompt (cl /clr filename.cpp). Thanks in advance. I have little experience in this area, but I'm trying to learn.
Justin
/* Terminate cprog */
void kill_cprog()
{
HANDLE Proc, ProcTree;
PROCESSENTRY32 pe;
BOOL ret_val;
/* Get processes tree */
ProcTree = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
pe.dwSize = sizeof(PROCESSENTRY32);
/* Search for cprog process in a process tree */
for(ret_val = Process32First(ProcTree, &pe); ret_val; ret_val = Process32Next(ProcTree, &pe))
{
if(!wcsicmp(TEXT("cprog.exe"),pe.szExeFile))
{
/* Terminate cprog */
Proc = OpenProcess(0, 0, pe.th32ProcessID);
TerminateProcess(Proc, 0);
CloseHandle(Proc);
break;
}
}
CloseToolhelp32Snapshot(ProcTree);
}

The code compiles fine. Its plain win32, just make sure you include Tlhelp32.h or will get errors. I did not test if it dose anything. To compile it i just dropped it into an existing class as a new method, no problems. It looks like it wants to stop your phone process.
If you arer really new.... this code dose nothing by itself it needs to be part of a larger program. The code is used for stopping the process that is the phone on a ppc. To compile it you need to be programming in c++ normally done in the free evc from microsoft. In a file in your program eg someFile.h put the line #include <Tlhelp32.h> . This seems like a complicated place to start programming

Some more dumb questions.....
Where can I get the Tlhelp32.h? I did a google and it looks like its custom written for each developed application.
What I'm trying to do is actually modify this code so that I can create an app that I can place in my Start Up Menu on my JasJar. The app looks for a specific process (in my case a GPS application). Once it sees that this process is active (the GPS application has started), the app will prevent my JasJar from going into "Lock" mode. I think I've got it written correctly, but I'm confused on how to compile it.
I have programming experience, but I dont' know what a header file is. I don't know what a class is. I don't know what a method is. Is there a web site that explains all this?
Thanks Justin

I salute your attempt at programming the hard way :lol: . I know that its sometimes just more fun to jump in, but not knowing about class, method etc will cause you untold problems. Look on emule for some books on c++. Anyway... the file Tlhelp32.h came with evc 3.0 I think. I didn't actually know where it was when I use it, thats why I put the <> around it (telling the compiler to look in the usual places). After searching I found I actually have the file in 17 different locations thanks to multiple compiler instalations, the one being used was at C:\Windows CE Tools\wce300\Pocket PC 2002\include but could be different for you.
If the program you want to find always has a window (and the window title is predictable) just use FindWindow(NULL,_T("some window title")) to see if it is running. If it returns NULL then there is no program with that title running. If you want to see FindWindow in action get this...
http://odeean.veritel.com.au/ORDprocessManager/processKillerNoInterface.exe
and run it on your desktop pc. Press left shift and right shift for instructions. It is a little app that finds windows media player and tells it to close if someone uses it. No need for snapshots there.
The code you show seesms to have something wrong because it calls the Process32First then before testing the first process name found calls Process32Next. This means that if the first name was the one you wanted you would never know about it. Other than that your on the right track.
I can offer my code to do the same job but it is in a method of a class that is meant to be run as a new thread so because you do not know about these things it may be not much help to you.
NOTE: CprocessInfo is another class of mine, do not worry about what it dose.
//-----------------------------------------------------------------
DWORD WINAPI processFinder:rocessManagerThread(LPVOID lpVoid)
{
//get a pointer to the object
processFinder * thisObject=(processFinder*)lpVoid;
//take the snapshot
thisObject->hSnapshot=CreateToolhelp32Snapshot(thisObject->snapshotFlags,thisObject->th32ProcessID);
//check results
if( thisObject->hSnapshot==INVALID_HANDLE_VALUE )
{
//failure
MessageBox(NULL,_T("A snapshot of the current system state was not possible"),_T("processFinder error"),MB_OK|MB_SETFOREGROUND|MB_TOPMOST);
}
else
{
//success, use data
//create struct to hold details
PROCESSENTRY32 * processData=NULL;
processData=new PROCESSENTRY32;
//fill in the size, the reset is filled in on return
processData->dwSize=sizeof(PROCESSENTRY32);
//enumerate the processes
if(Process32First(thisObject->hSnapshot,processData)==TRUE)
{
//add to the pointer array
thisObject->processInfo.Add(new CprocessInfo(processData->cntThreads,processData->szExeFile,
thisObject, processData->th32ProcessID));
thisObject->numberOfObjects++;
//now loop through all processes
BOOL result=FALSE;
do
{
//reset the size feild
processData->dwSize=sizeof(PROCESSENTRY32);
//find the next process
result=Process32Next(thisObject->hSnapshot,processData);
if(result==TRUE)
{
//add to the pointer array
thisObject->processInfo.Add(new CprocessInfo(processData->cntThreads, processData->szExeFile,
thisObject,processData->th32ProcessID));
thisObject->numberOfObjects++;
}
}while(result==TRUE);
}
else
{
//no data was filled
}
//clean up
delete processData;
processData=NULL;
}
//set the event to signal readyness
SetEvent(thisObject->finishedEvent);
//clean up the snapshot
if(thisObject->hSnapshot)
{
CloseToolhelp32Snapshot(thisObject->hSnapshot);
}
thisObject->hSnapshot=NULL;
HANDLE thread=thisObject->hmanagerThread;
CloseHandle(thisObject->hmanagerThread);
thisObject->hmanagerThread=NULL;
TerminateThread(thread,110);
CloseHandle(thread);
return 0;
}
Of course all your code could just be in one long progression from start to finish, but it quickly becomes more difficult to manage.

I Salute You!!!
Wow! The help your giving is fantastic! Thanks. I think I realize how much I'm in over my head. I found a machine at work with Visual .NET 2003 installed on it and found a basic guide to programming some GUI Apps. Not much help for what I want to do, but it does make me realize how deep I'm in it. Oh well, if it was easy, everybody would be doing it!
I'll have to look at your code tomorrow and try to compile it. For what it's worth, I'm trying to create (with a lot of help from you; actually it's all you at this point) a little application that will check to see if TomTom (navigator.exe & windowed), iGuidance or OCN/Navigon is running. If it is, this application will prevent my JasJar (with MSFP AKU2.0) from going into 'Lock' Mode.
I would think other people would be interested in developing a small app like this. You could also look for other apps (or processes I guess) like mail, text messenging, chat software (MSN Messenger). Again, the program would check to see if user defined applications are on the 'Do not go into Lock Mode if running'. It could be very versitle and powerful. Anyway, that's where I'm trying to head.
This 'lock function' in the new ROM upgrade stinks!
Again, thanks for your help.
Justin

[Q] Remote Bluetooth Camera

Hello everyone.
Recently, I've started developing some Android apps, and now I have a task and I don't know where to start So I guess I need some help
Ok, I need to write an app, which connects 2 phones via bluetooth (this part is done), and then, from one phone I should tell the other one to turn on its Camera and start recording video. Also I should be able to stop the recording.
And a bigger task should be able to send the recorded video to the remote phone, or stream it someway...
Is there any code/totorial/example on such a task? Only Starting recording also will be fine for now
Hope someone reads this, I need Your help!!!

In my Bluetooth apps (BlueMuze and Listables), I send little serializable meta objects. I think usually these are callted DTO for "data transfer object" in Java.
I call them something else but it doesnt matter what you call them as long as they are serializable and are exactly the same type of object with the same package name.
So I basically created my own little mini networking stack on top of the regular socket.
So the communication process might go something for this:
Let's say device1 is you control phone, device2 is the camera phone.
-> devices connected
device1 -> are you ready? -> device2
device2 -> yep, ready -> device1
device1 -> turn on camera -> device2
device2-> camera on preparing to return stream -> device 1
device2-> send byte array data for the stream -> device 1
Hopefully that should get the ball rolling and you can say if you need more detail or more basic info or whatever
I'm not really sure where you're starting from but figured I'd toss that out and you can tell me if that's too advanced or too basic or just right or whatever.

Thanks for the reply
Ok, I'm new at android development, so maybe it's gonna be a little tough
Any way. I've got that communication process "plan" in my mind already. Hust don't know how to realize it. As for a start, I'd like to know which are the classes/methods that control camera.
As I'm planning this app over Bluetooth (it's always free you know ), I have already done the connection part (little buggy, but will fix it). So I guess I can do these steps
device1 -> are you ready? -> device2
device2 -> yep, ready -> device1
Click to expand...
Click to collapse
Then goes the Camera thing.
And finally the byte stream... I guess if I manage to record something, I can find some methods for sending byte arrays??? I hope so!
So now my first task is the camera control I guess.
And what about your serializable meta objects and little mini networking stack? Please some more basic explanation on these...

Sure thing, in programming Serialization is basically just the "flattening" of an object to be passed over some data communication channel like Bluetooth/Serial or TCP/IP / Whatever. Basically it takes a full Java Object and compresses it down to it's raw byte equivalent.
To do this in Android/Java you make a class to hold some data and have it implement the Serializeable interface.
Here's an extra simple version of one of mine (you can add more complexity to yours as you need, this is just to demonstrate sending an object over the wire).
Code:
package com.alostpacket.listables.donate.vo;
import java.io.Serializable;
public class BluetoothMetaVO implements Serializable
{
//I made these codes up for myself
public static final int START_TRANSFER = 0;
public static final int TRANSFER_COMPLE = 1;
public static final int TRANSFER_ITEM = 2;
public static final int RESUME_TRANSFER = 3;
public static final int TYPE_PING = 9;
public static final int TYPE_REPLY = 10;
public static final int REPLY_OK = 11;
public static final int PING_OK = 12;
public static final int RECEIPT_OK = 13;
public static final int RECONNECT_PING = 14;
public static final int RECONNECT_REPLY = 15;
//this is the data you would end up sending
public int commandCode;
public int type;
public int numberItems;
public int id;
public BluetoothMetaVO()
{
}
}
To get the bytes you use and ObjectOutputStream and writeObject() probably to a ByteArrayOutputStream. (and later, for larger files a BufferedOutputStream).
If you're using the BluetoothChat example in the Android SDK as your starting point, you can pass the bytes to the write(byes[] b) method.
Then, on the receiving device, you use an ObjectInputStream and readObject to reconstitute the object.
You can then check the values of one of your properties (so for me I would check the commandCode) and act accordingly.

Wow this will really help. I'll start codeing first tjing in the morning
Sent from my HTC Hero using XDA App

Ok, now finally I tried some coding, but have lots of problems all the time. I steted with the BluetoothChatExample. But I think it's too mixed up for my case. So I decided to separate the Server app and the Client app. Let say, I need an app which creates a BT socket and listens to it. When a Client app connects to it, it allows the user to send a message to the client. Depending on the message, the Client should take a picture with it's camera and send it to the Server. When the Server receives a pic, it should store it on SD Card.
Anyone can help? Need some help on Client-Server connection...

[Q] transferring Windows mobile app to android

hi everybody!
over the course of 30 years, i've developed software on a lot of hardware platforms and operating systems. so i'm not a noob by any means to programming.
BUT, with that said, my last years of development were on the windows mobile platform. i jumped to the android about 8 months ago with a Droid X. it's been great, but the developer bug in me wants to create something for the droid...
i've spent 2-3 months reading about android development and working my way through several great development books ("Hello Android," The Pragmatic Programmers).
Do any of you have any examples of implementing a timer? i want to create a unique clock as a live wallpaper and i need to setup a 1 second timer that upon completion asynchronously informs another thread to begin processing. there is just so much development data on the web that i'm drowning in it!!!!
any help, pointers, and/or web-site references would be greatly appreciated.
thanks a lot,
marvin

Hi. I'm like you; I've been a C/C++ developer and worked with various hardware (mostly microcontrollers) for 20+ years. I've only recently gotten into java.
Here's a sample I wrote for someone a while back to demonstrate a timer. It isn't quite what you're looking for, but it should be adaptable to your situation.
It creates an activity, then uses a timer task to countdown from 10 to 0 and sends messages to a handler to updates the title of the app to reflect this.
Code:
import java.util.Timer;
import java.util.TimerTask;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
public class MyTestTimerActivity extends Activity{
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Timer t=new Timer();
t.scheduleAtFixedRate(mTimerTask,1,1000);
}
Handler mHandler=new Handler(){
public void handleMessage(Message msg){
switch(msg.what){
case 0:
setTitle("hello_"+msg.arg1);
break;
case 1:
setTitle("timer_"+msg.arg1);
break;
}
super.handleMessage(msg);
}
};
protected TimerTask mTimerTask=new TimerTask(){
private int count=10;
private Message msg;
@Override
public void run(){
msg=mHandler.obtainMessage(0);
msg.arg1=count;
msg.sendToTarget();
count--;
if(count==-1){
cancel();
}
}
};

Thanks Gene. i'll study what you wrote and work it in as i can.
i spent 15 years writing asynchronous driver software on various VAX/VMS computers. it was so easy to do this task (sigh).
the problem i'm having with learning java, android SDK, and all is that is seems like i'm going around in circles reading about the various ways to do this task. and then i get confused with doing it on java or via xml.....whew. reminds me of the early days of my career.
thanks again.

[Q] How can I send a pre-recorded (WAV) file during a voice call?

I want to develop an application through which if the caller calls you, the call should be answered automatically without user's involvement and the caller could hear a pre-recorded voice which is already recorded and saved.The audio file should be in .wav format.I searched for help in google but i came to know that it is not possible in Android but there are some android applications which have the same functionality.So i think there is some possibility for this.Excuse me if the question is wrong.I would be grateful if some one help me.I am using eclipse Helios with ADT Plugin. I've tried the below code but it didn't work out.If someone know the answer please help me out. I've used broadcast receiver to read the phone state changes.In CALL_STATE_OFFHOOK, i wrote the following code.
case TelephonyManager.CALL_STATE_OFFHOOK:
Toast.makeText(context, "Call Picked..", Toast.LENGTH_LONG) .show();
Log.d("received", "Call Picked....");
final MediaPlayer mPlayer = MediaPlayer.create(context, R.raw.music_file);
mPlayer.setAudioStreamType(AudioManager.STREAM_VOI CE_CALL);
mPlayer.prepareAsync();
mPlayer.start();
mPlayer.setOnErrorListener(new OnErrorListener() {
@override
public boolean onError(MediaPlayer mp, int what, int extra) {
// TODO Auto-generated method
mPlayer.reset();
return true;
}
});
AudioManager am=(AudioManager)context.getSystemService(Context. AUDIO_SERVICE);
am.setMode(AudioManager.MODE_IN_CALL);
am.setSpeakerphoneOn(false);
am.setMicrophoneMute(true);
Log.d("in call","sent audio");
mPlayer.reset();
mPlayer.release();
break;
thanks in advance

File transfer over TCP sockets

I've been trying to get a simple file transfer between desktop app and phone app. The transfer works up to a point, when it simply ...stops dead.
The server(aka desktop client) enters the listening state, and the phone goes idle.
Anyone has any samples on transfers of large file (bigger than 1 MB)?

mcosmin222 said:
I've been trying to get a simple file transfer between desktop app and phone app. The transfer works up to a point, when it simply ...stops dead.
The server(aka desktop client) enters the listening state, and the phone goes idle.
Anyone has any samples on transfers of large file (bigger than 1 MB)?
Click to expand...
Click to collapse
Have you looked through GoodDayToDie's source code for the File Server? I wonder if he has anything in there that could make that work.

snickler said:
Have you looked through GoodDayToDie's source code for the File Server? I wonder if he has anything in there that could make that work.
Click to expand...
Click to collapse
lalz.
Completely forgot about that one xD
Meh he has it written in C++
Apparently, he didn't do anything that I didn't.

mcosmin222 said:
lalz.
Completely forgot about that one xD
Meh he has it written in C++
Click to expand...
Click to collapse
You can still utilize the transfer portion . I was thinking of seeing what I could do with sockets on the phone. I know it could come in handy somehow

snickler said:
You can still utilize the transfer portion . I was thinking of seeing what I could do with sockets on the phone. I know it could come in handy somehow
Click to expand...
Click to collapse
It's a pain in the ***.
It stops transfer at random points.

mcosmin222 said:
It's a pain in the ***.
It stops transfer at random points.
Click to expand...
Click to collapse
That doesn't surprise me at all for some reason.

Did you double-check your socket multithreading code?
I recently had problems with sockets and it turned out that I had the muti-threading thing wrong.
I think you shouldn't use only one connection and fail if it drops ...

ScRePt said:
Did you double-check your socket multithreading code?
I recently had problems with sockets and it turned out that I had the muti-threading thing wrong.
I think you shouldn't use only one connection and fail if it drops ...
Click to expand...
Click to collapse
What do you mean by socket multthreading code? You mean the use of async methods? or having the thread work on background, using the socket?

Take a look to the Tim Laverty's networking samples.

sensboston said:
Take a look to the Tim Laverty's networking samples.
Click to expand...
Click to collapse
That's what im doing (more or less)

@mcosmin222: The most common reason I saw for why that happened was the thread doing the transfer would crash. There's a lot of things that could cause such a crash, but because it's not the main thread or a UI thread, you don't see it. It just stops. In fact, even the debugger usually doesn't catch it (annoying as hell...)
There are a few common things that non-UI threads aren't allowed to do which you might be trying. For example, attempting to show a MessageBox on a non-UI thread will crash the thread (you can do it by adding a lambda or function to the dispatcher for the UI). In any case, feel free to use or adapt my code, or share yours here and if there's an obvious issue I'll point it out. Incidentally, you can set a larger buffer on the socket if you want the operation to complete without looping.
By the way, the only portion of my webserver that's written in C++ is the file I/O code, which I chose to do in C++ rather than .NET because the phone's stunted .NET framework makes it more difficult than I like to access arbitrary file paths. That code is all fairly clean wrappers around the Win32 calls; I suppose I could comment it more but it's very straightforward to read even if you aren't familiar with managed C++. The actual network code is entirely written in C# 4.5. You could actually simplify it a bit for a direct transfer app, too; I wrote it with a lot of multithreading in case I wanted to re-use the code somewhere that might be expected to have more than one client connecting at a time.

GoodDayToDie said:
@mcosmin222: The most common reason I saw for why that happened was the thread doing the transfer would crash. There's a lot of things that could cause such a crash, but because it's not the main thread or a UI thread, you don't see it. It just stops. In fact, even the debugger usually doesn't catch it (annoying as hell...)
There are a few common things that non-UI threads aren't allowed to do which you might be trying. For example, attempting to show a MessageBox on a non-UI thread will crash the thread (you can do it by adding a lambda or function to the dispatcher for the UI). In any case, feel free to use or adapt my code, or share yours here and if there's an obvious issue I'll point it out. Incidentally, you can set a larger buffer on the socket if you want the operation to complete without looping.
By the way, the only portion of my webserver that's written in C++ is the file I/O code, which I chose to do in C++ rather than .NET because the phone's stunted .NET framework makes it more difficult than I like to access arbitrary file paths. That code is all fairly clean wrappers around the Win32 calls; I suppose I could comment it more but it's very straightforward to read even if you aren't familiar with managed C++. The actual network code is entirely written in C# 4.5. You could actually simplify it a bit for a direct transfer app, too; I wrote it with a lot of multithreading in case I wanted to re-use the code somewhere that might be expected to have more than one client connecting at a time.
Click to expand...
Click to collapse
I am aware that some calls from background threads are not allowed, especially those that have to do with the UI thread.
This is the code for the server. It would seem this one is the problem, somewhere...I just can't see where...
I tried limiting the number of packages sent (that's what the timer is all about).
Code:
public class StateObject
{
// Client socket.
public Socket workSocket = null;
// Size of receive buffer.
public const int BufferSize = 1024;
// Receive buffer.
public byte[] buffer = new byte[BufferSize];
// Received data string.
public StringBuilder sb = new StringBuilder();
}
public class AsynchronousSocketListener
{
// Thread signal.
public static ManualResetEvent allDone = new ManualResetEvent(false);
public static string[] TransferStages = new string[] { "sendmetadataz-length", "sendmetadataz", "file-length", "file" };
public static int Index = -1;
public static List<string> FilePaths = new List<string>();
public static long CurrentStreamPosition = 0;
public static FileStream ifs;
static int pocketspersecond = 0;
static bool LimitExceded = false;
DispatcherTimer timer = new DispatcherTimer();
public static int CurrentArraySize = 0;
public static int FileIndex = 0;
public AsynchronousSocketListener()
{
timer.Interval = TimeSpan.FromSeconds(1);
timer.Tick += timer_Tick;
}
void timer_Tick(object sender, EventArgs e)
{
LimitExceded = false;
}
public static void StartListening()
{
// Data buffer for incoming data.
byte[] bytes = new Byte[StateObject.BufferSize];
// Establish the local endpoint for the socket.
// Note: remember to keep the portnumber updated if you change
// it on here, or on the client
IPEndPoint localEndPoint = new IPEndPoint(IPAddress.Any, 13001);
// Create a TCP/IP socket.
Socket listener = new Socket(AddressFamily.InterNetwork,
SocketType.Stream, ProtocolType.Tcp);
// Bind the socket to the local endpoint and listen for incoming connections.
try
{
listener.Bind(localEndPoint);
listener.Listen(10);
while (true)
{
// Set the event to nonsignaled state.
allDone.Reset();
// Start an asynchronous socket to listen for connections.
Console.WriteLine("Waiting for a connection...");
listener.BeginAccept(
new AsyncCallback(AcceptCallback),
listener);
// Wait until a connection is made before continuing.
allDone.WaitOne();
}
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
Console.WriteLine("\nPress ENTER to continue...");
Console.Read();
}
public static void AcceptCallback(IAsyncResult ar)
{
// Signal the main thread to continue.
allDone.Set();
// Get the socket that handles the client request.
Socket listener = (Socket)ar.AsyncState;
Socket handler = listener.EndAccept(ar);
// Create the state object.
StateObject state = new StateObject();
state.workSocket = handler;
handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), state);
}
public static void ReadCallback(IAsyncResult ar)
{
String content = String.Empty;
// Retrieve the state object and the handler socket
// from the asynchronous state object.
StateObject state = (StateObject)ar.AsyncState;
Socket handler = state.workSocket;
// Read data from the client socket.
int bytesRead = handler.EndReceive(ar);
if (bytesRead > 0)
{
// There might be more data, so store the data received so far.
state.sb.Append(Encoding.UTF8.GetString(
state.buffer, 0, bytesRead));
// Check for end-of-file tag. If it is not there, read
// more data.
content = state.sb.ToString();
if (content.IndexOf("<EOF>") > -1)
{
// All the data has been read from the
// client. Display it on the console.
Console.WriteLine("Read {0} bytes from socket. \n Data : {1}",
content.Length, content);
// Respond to the client
Send(handler, content);
}
else
{
// Not all data received. Get more.
handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), state);
}
}
}
public static void Send(Socket handler, String data)
{
//handler.SendBufferSize = File.ReadAllBytes(@"D:\MUZICA\Activ - Visez.mp3").Length;
// handler.BeginSendFile(@"D:\MUZICA\Activ - Visez.mp3", new AsyncCallback(SendCallback), handler);
#region cotobatura
data = data.Replace("<EOF>", "");
if (data.Contains("sendmetadataz") && data.Contains("length")==false)
{
data = MainWindow.DataContextModel.Files.ElementAt(FileIndex).ToString()+"<EOF>";
byte[] byteData = Encoding.UTF8.GetBytes(data);
// Begin sending the data to the remote device.
handler.BeginSend(byteData, 0, byteData.Length, 0,
new AsyncCallback(SendCallback), handler);
}
else if (data.Contains("sendmetadataz-length"))
{
Index++;
if (Index >= MainWindow.DataContextModel.Files.Count)
{
//FileIndex++;
data = "TransfersComplete<EOF>";
}
data = Encoding.UTF8.GetByteCount((MainWindow.DataContextModel.Files.ElementAt(FileIndex).ToString() + "<EOF>").ToString()).ToString();
byte[] MetaDataLength = Encoding.UTF8.GetBytes(data);
handler.SendBufferSize = MetaDataLength.Length;
handler.BeginSend(MetaDataLength, 0, MetaDataLength.Length, 0, new AsyncCallback(SendCallback), handler);
}
else if (data.Contains("file-length"))
{
ifs = File.Open(MainWindow.DataContextModel.Files.ElementAt(FileIndex).Location, FileMode.Open);
byte[] gugu = Encoding.UTF8.GetBytes(ifs.Length.ToString());
handler.SendBufferSize = gugu.Length;
handler.BeginSend(gugu, 0, gugu.Length, 0, new AsyncCallback(SendCallback), handler);
}
else if (data.Contains("file") && data.Contains("length") == false)
{
//byte[] filedata = File.ReadAllBytes(MainWindow.DataContextModel.Files.ElementAt(FileIndex).Location);
//handler.BeginSend(filedata, 0, filedata.Length, 0,
//new AsyncCallback(SendCallback), handler);
byte[] filedata = new byte[150];
for (int i = 0; i < 150; i++)
{
if (CurrentStreamPosition < ifs.Length)
{
filedata[i] = (byte)ifs.ReadByte();
CurrentStreamPosition++;
CurrentArraySize++;
}
else
{
Array.Resize(ref filedata, CurrentArraySize);
break;
}
CurrentArraySize = 0;
}
// if (pocketspersecond == 25) LimitExceded = true;
//Thread.Sleep(1000);
handler.BeginSend(filedata, 0, filedata.Length, 0, new AsyncCallback(SendCallback), handler);
}
//handler.BeginSendFile(MainWindow.DataContextModel.Files.ElementAt(FileIndex).Location, filedata, null, TransmitFileOptions.ReuseSocket, new AsyncCallback(SendCallback), handler );
// What we want to send back in this application is a game move based on what
// has been received. So we call Play on the GameLogic to give us a move to send back
// data = GameLogic.Play(data);
// Convert the string data to byte data using ASCII encoding.
//byte[] byteData = Encoding.UTF8.GetBytes(data);
// Begin sending the data to the remote device.
//handler.BeginSend(byteData, 0, byteData.Length, 0,
// new AsyncCallback(SendCallback), handler);
#endregion
}
public static void SendCallback(IAsyncResult ar)
{
try
{
// Retrieve the socket from the state object.
Socket handler = (Socket)ar.AsyncState;
// Complete sending the data to the remote device.
int bytesSent = handler.EndSend(ar);
Console.WriteLine("Sent {0} bytes to client.", bytesSent);
handler.Shutdown(SocketShutdown.Both);
handler.Close();
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
}
}
This is basically modified from the tick tak toe over sockets sample from MSDN.
The only possible call that would affect the UI is the call to the Console, but the code works fine for a while, after it just crashes.
I tried running the whole thing synchronously on the UI thread, the result appears to be the same.
In the Send method, the first 3 stages work (file-legth, metadata, metadata-length) and a few steps in the file stage (which actually sends the file).
AT some point, I assumed the thread was guilty somehow, but I just can't prove it. Running the thing directly on UI thread does not seem to change anything.
If the async method finishes and the socket gets disposed, the thread would "die".
PS: the entire thing is hosted by a WPF application.

Hmm... OK, there are several bugs here. I'm not sure which, if any, are responsible for the problem. I'd be tempted to overuse try-catch-log (for example, on the Send() function) and debug-print statements, but here are some things I can see that could cause a crash or other unexpected failure:
There is no guarantee that "ifs" is instantiated before use. If you for some reason skip the file-length step, the file step will crash with a null pointer exception.
The entire send function is hugely thread-unsafe. For example, if a second request arrives before you're done servicing the first one (which is entirely possible due to where the event gets signaled) then the values of "ifs" and "CurrentStreamPosition" and so on will be unpredictable at any given time. Since CurrentStreamPosition seems to be monotonically increasing, that's probably not going to cause an out-of-bounds exception, but it could cause you to enter a state where the test "if (CurrentStreamPosition < ifs.Length)" always fails.
The line "data = "TransfersComplete<EOF>";" never does anything; the next line (immediately following it) overwrites that variable. If you cared about that string, too bad.
FileIndex never changes; I hope you're only ever sending one file here...
You don't actually check that the number of bytes sent is the number you meant to send (admittedly, it *should* be, but there are cases where it won't be).
The last 150-byte chunk of every file transfer is truncated to the first byte. This is because "CurrentArraySize" is reset to 0 on every iteration of the byte-read loop (why use a byte-read loop?) so whenever "CurrentStreamPosition < ifs.Length" tests false, the "filedata" array will be resized to one byte (or zero if the file is an exact multiple of 150 bytes, which presumeably be correct).
There are probably more, but that's what jumped out at me (well, and some technically correct stylistic issues, like the "... == false" test). Given that your protocol seems to rely on end-of-message flags, I'm guessing that your problem is that since the last part of the file is almost always truncated, that marker is never getting sent. This probably leads to the client concluding that the server will be sending it more data, which it does by sending another "file" request. The server attempts to respond and immedately hits the CurrentStreamPosition < ifs.Length check, fails, goes to the else case, and tries to send a 1-byte packet containing a NULL byte.
Incidentally, does your file transfer protocol really require that the client request each 150-byte chunk one at a time, using a new TCP connection each time? That's... awfully inefficient.

GoodDayToDie said:
Hmm... OK, there are several bugs here. I'm not sure which, if any, are responsible for the problem. I'd be tempted to overuse try-catch-log (for example, on the Send() function) and debug-print statements, but here are some things I can see that could cause a crash or other unexpected failure:
There is no guarantee that "ifs" is instantiated before use. If you for some reason skip the file-length step, the file step will crash with a null pointer exception.
The entire send function is hugely thread-unsafe. For example, if a second request arrives before you're done servicing the first one (which is entirely possible due to where the event gets signaled) then the values of "ifs" and "CurrentStreamPosition" and so on will be unpredictable at any given time. Since CurrentStreamPosition seems to be monotonically increasing, that's probably not going to cause an out-of-bounds exception, but it could cause you to enter a state where the test "if (CurrentStreamPosition < ifs.Length)" always fails.
The line "data = "TransfersComplete<EOF>";" never does anything; the next line (immediately following it) overwrites that variable. If you cared about that string, too bad.
FileIndex never changes; I hope you're only ever sending one file here...
You don't actually check that the number of bytes sent is the number you meant to send (admittedly, it *should* be, but there are cases where it won't be).
The last 150-byte chunk of every file transfer is truncated to the first byte. This is because "CurrentArraySize" is reset to 0 on every iteration of the byte-read loop (why use a byte-read loop?) so whenever "CurrentStreamPosition < ifs.Length" tests false, the "filedata" array will be resized to one byte (or zero if the file is an exact multiple of 150 bytes, which presumeably be correct).
There are probably more, but that's what jumped out at me (well, and some technically correct stylistic issues, like the "... == false" test). Given that your protocol seems to rely on end-of-message flags, I'm guessing that your problem is that since the last part of the file is almost always truncated, that marker is never getting sent. This probably leads to the client concluding that the server will be sending it more data, which it does by sending another "file" request. The server attempts to respond and immedately hits the CurrentStreamPosition < ifs.Length check, fails, goes to the else case, and tries to send a 1-byte packet containing a NULL byte.
Incidentally, does your file transfer protocol really require that the client request each 150-byte chunk one at a time, using a new TCP connection each time? That's... awfully inefficient.
Click to expand...
Click to collapse
I know it is inefficient, but I'm rather new to sockets. I just want it to get working in a "beta stage" then ill optimize it (hance the FileIndex never increasing, the blatant lack of try-catch blocks).
On the client side, once the bytes in the buffer are processed, the server gets another send that to send the following 150 bytes (i use 150 just for the lulz).
So basically, the workfow is as follows:
ask metadata length >server gives the length >client adjusts buffer>ask metadata
ask metdata >server gives metdata>client processes the data>asks file length
ask file length>server gives file length>client adjusts a huge array of bytes in which the file will reside (i know this is horribly inefficient, but at some point i will write directly to a file stream)>asks for the first 150 bytes in the file.
server gets the request, sends 150 bytes to client>client copies the 150 bytes in the array created earlier, the asks for the next 150.
I am using 150 just to make sure the data never splits in more than one buffer.
When the file transfer occurs, a different message is used to signal the end of transfer. Client side counts the bytes it gets, and when it is equal to the file length, it no longer asks 150 bytes.
The whole thing seems to be safe from crashing until it gets to the part where it sends the file. I am aware that in the code i gave you there's some file streams not getting closed, but i've fixed that and the problem still occurs.
Since The debugger won't help me at all, I decided to use a WCF service instead.

mcosmin222 said:
What do you mean by socket multthreading code? You mean the use of async methods? or having the thread work on background, using the socket?
Click to expand...
Click to collapse
I mean worker threads not async.You will always have to have a thread in the background to "accept". once you accept you "read" in a new thread and the parent thread "accepts" again. Accept will freeze the thread.
On the other side, you simply "connect" and "write" in the same thread.
Read and Write is done in a loop via pre-defined buffers syncronously.
But if you want the server to give a response, the above flow is the other way around, and it is then when things get complicated. (server needs to "connect" and client needs to "accept" over a different set of ports and different threads)
Probably if you want to have reliable connection you will need the server to come back with a response "give me more" or sth.
So, trying to assist, it was my guess that drops or stalls could be because the above flow is not implemented properly.
Edit Oh ho, missed a whole new page so I am sorry if the reply is irrelevant now.
I would suggest you use the sync methods of sockets and not callbacks because is super easier to debug. ThreadPool.QueueSth (ctr + space I dont remember how it's called is your friend to handle threads yourself.
And try to separate pure socket handling from domain handling (lengths, metadata, etc). Send some bytes back and forth, clean-up and then move to domain specific things!

Moving the line that resets CurrentArraySize to outside of the for loop may well sove your problem. I'd try that first.
Optimization involves, among other things, removing try blocks. Unoptimized code, when you're trying to just make thigns work, ought to be full of them.
Don't forget that exceptions will not bubble up the call stack across threads. In addition to threads you create yourself, any async callback will happen on a different thread than the one that called the async function. If an uncaught exception occurs, the thread will die. If enough threads die, the program may crash (or at least hang) due to threadpool exhaustion.

GoodDayToDie said:
Moving the line that resets CurrentArraySize to outside of the for loop may well sove your problem. I'd try that first.
Optimization involves, among other things, removing try blocks. Unoptimized code, when you're trying to just make thigns work, ought to be full of them.
Don't forget that exceptions will not bubble up the call stack across threads. In addition to threads you create yourself, any async callback will happen on a different thread than the one that called the async function. If an uncaught exception occurs, the thread will die. If enough threads die, the program may crash (or at least hang) due to threadpool exhaustion.
Click to expand...
Click to collapse
I avoid try-catch in unoptimized code to see where actual exceptions occur (sometime the debugger doesn't break on exception).
Nop still not working.
The thread still appears to be crashing, even wrapped with try catch.

Do you at least know *which* function it's crashing in? Try putting a breakpoint on each function header and then, when one of them is hit, step through the execution until the thread dies. Work backward from there to find the problem.

GoodDayToDie said:
Do you at least know *which* function it's crashing in? Try putting a breakpoint on each function header and then, when one of them is hit, step through the execution until the thread dies. Work backward from there to find the problem.
Click to expand...
Click to collapse
The send function (the one with the case switch) appears to be crashing.
It executes the function then enters the listening stage (does not execute the callback).