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Sending a memory Stream array over Socket from C# to C Server

I want to send a prebuffer memory stream array from C# client to C server but I'm not sure how to receive it on the C end .
it currently only detects the overall size which is being placed first in the array but is not recognizing nor the name or the name size of the file .
How should I approach this problem ?
C# Code
public static void SendFile(Socket clientSocket, string fileName)
{
string fullPath = MainWindow.folder + fileName;
if (File.Exists(fullPath))
{
FileInfo fi = new FileInfo(fullPath);
long file_size = fi.Length;
byte[] preBuffer;
using (var memoryStream = new MemoryStream())
{
using (BinaryWriter writer = new BinaryWriter(memoryStream))
{
writer.Write(file_size);
writer.Write(fileName.Length);
writer.Write(fileName);
}
preBuffer = memoryStream.ToArray();
Console.WriteLine(preBuffer);
clientSocket.Send(preBuffer);
}
}
}
C Code
main function
bool write_data(SOCKET sock, FILE *f)
{
long filesize;//size of address
int file_name_len;
char buffer[BUFFER_SIZE];
if (!recv_file_len(sock, &filesize)) { return false; }
printf("file size (From C#) : %ld\n", filesize);
if (!recv_file_name_len(sock, &file_name_len)) { return false; }
printf("file_name_len (From C#) : %d\n", file_name_len);
char * file_name = malloc(sizeof(char) * file_name_len);
if (!recv_file_name(sock, file_name)) { return false; }
printf("file_name (From C#) : %s\n", file_name);
}
Additional functions for recv
/*
============================================
General : function is responsible for receiving a length of data from the client
Parameters : sock - client socket to receive the data from
*buf - holds a pointer to the buffer that needs to update
bufsize - the length of the buffer
Return Value : returns TRUE when the data is read correctly
else, FALSE when there was a socket error or no bytes are received.
============================================
*/
bool recv_raw(SOCKET sock, void* buf, int bufsize)
{
unsigned char* pbuf = (unsigned char*)buf;
while (bufsize > 0) {
int num = recv(sock, pbuf, bufsize, 0);
if (num <= 0) { return false; }
pbuf += num;
bufsize -= num;
}
return true;
}
/*
===================================================
General : receives the length of the file and updates it
Parameters : sock - client socket to receive the data from
*filesize - holds a pointer to the size of the buffer that needs to update
filesize_len - the length of the file size pointer
Return Value : returns TRUE when the size is read correctly
else, FALSE when there was a socket error or no bytes are received.
===================================================
*/
bool recv_file_len(SOCKET sock, long* filesize)
{
if (!recv_raw(sock, filesize, sizeof(*filesize))) { return false; }
return true;
}
bool recv_file_name_len(SOCKET sock, int* name_len)
{
if (!recv_raw(sock, name_len, sizeof(*name_len))) { return false; }
return true;
}
bool recv_file_name(SOCKET sock, char* name)
{
if (!recv_raw(sock, name, sizeof(*name))) { return false; }
return true;
}

Sending multiple files from C# to C

I have a wpf gui that I want to upload files from and send to a C client .
I want to send 3 files and for some reason 1 of them is being sent and written (but it adds 8 nulls in the end and removes 4 of the first letters in the file)
and in the other two when I try to receive the size it says their size is 0
I've been stuck on this problem for a while now and i'm becoming depserate as i'm probably missing a small thing , if any of u could give a hand that'll mean a lot ! I really wanna know whats the problem in my code.
I have the files paths in an array and sending it in main like so
C# Main
IPEndPoint ipPoint = new IPEndPoint(IPAddress.Parse("127.0.0.1"), 5555);//switch the port
Socket listenSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
listenSocket.Bind(ipPoint);
listenSocket.Listen(1);
Socket clientSocket = listenSocket.Accept();
for (int i = 0; i < 1; i++)
{
SendFile(clientSocket, filePaths[i]);
}
clientSocket.Shutdown(SocketShutdown.Both);
clientSocket.Close();
SendFile(C# side)
public static void SendFile(Socket clientSocket, string filePath)
{
if (File.Exists(filePath))
{
FileInfo fi = new FileInfo(filePath);
long file_size = fi.Length;
byte[] preBuffer;
using (var memoryStream = new MemoryStream())
{
using (BinaryWriter writer = new BinaryWriter(memoryStream))
{
writer.Write(file_size);
}
preBuffer = memoryStream.ToArray();
byte[] fixedBuffer = new byte[4];
Array.Copy(preBuffer, 0, fixedBuffer, 0, 4);
Console.WriteLine(BitConverter.ToString(preBuffer));
Console.WriteLine(BitConverter.ToString(fixedBuffer)); //fixing the problem i had with the converting to array that it added 4 useless zeros.
clientSocket.Send(fixedBuffer); // sending size
}
byte[] data = new Byte[4096];
using (FileStream fs = new FileStream(filePath, FileMode.Open))
{
int actualRead;
do
{
actualRead = fs.Read(data, 0, data.Length);
clientSocket.Send(data);
file_size -= actualRead;
} while (file_size - filePath.Length > 0);
}
}
else
{
MessageBox.Show("File for the program is missing! lua/pcap/csv");
}
}
C Receive(built from 3 functions)
/*
============================================
General : function is responsible for receiving a length of data from the client
Parameters : sock - client socket to receive the data from
*buf - holds a pointer to the buffer that needs to update
bufsize - the length of the buffer
Return Value : returns TRUE when the data is read correctly
else, FALSE when there was a socket error or no bytes are received.
============================================
*/
bool recv_raw(SOCKET sock, void* buf, int bufsize)
{
unsigned char* pbuf = (unsigned char*)buf;
while (bufsize > 0) {
int num = recv(sock, pbuf, bufsize, 0);
if (num <= 0) { return false; }
pbuf += num;
bufsize -= num;
}
return true;
}
/*
===================================================
General : receives the length of the file and updates it
Parameters : sock - client socket to receive the data from
*filesize - holds a pointer to the size of the buffer that needs to update
filesize_len - the length of the file size pointer
Return Value : returns TRUE when the size is read correctly
else, FALSE when there was a socket error or no bytes are received.
===================================================
*/
bool recv_file_len(SOCKET sock, long* filesize)
{
if (!recv_raw(sock, filesize, sizeof(*filesize))) { return false; }
return true;
}
/*
================================================== =
General : writes to the lua file the data from the file
that was received in the socket
Parameters : sock - the socket between the client and server
*f - the file to write the data received to
Return Value : returns TRUE when everything was written to the file.
returns FALSE if there's no data received or detected a socket problem.
================================================== =
*/
bool write_data(SOCKET sock, FILE *f)
{
long filesize;//size of address
char buffer[BUFFER_SIZE];
if (!recv_file_len(sock, &filesize)) { return false; }
printf("file size (From C#) : %ld\n", filesize);
int n = recv_raw(sock, buffer, 8); // need to get the size of the name
if (filesize > 0)
{
do {
int num = min(filesize, BUFFER_SIZE);
if (!recv_raw(sock, buffer, num)) {
return false;
}
int offset = 0;
do
{
size_t written = fwrite(&buffer[offset], 1, num - offset, f);
if (written < 1) { return false; }
offset += written;
} while (offset < num);
filesize -= num;
} while (filesize > 0);
}
return true;
}
C Main
FILE* luafhandler = fopen("test.lua", "wb");//the new lua file
if (luafhandler == NULL)
{
fclose(luafhandler);
printf("GUI CONNECT lua file failed to open!\n");
}
FILE* pcapfhandler = fopen("test.pcap", "wb");//the new lua file
if (pcapfhandler == NULL)
{
fclose(pcapfhandler);
printf("GUI CONNECT pcap file failed to open!\n");
}
FILE* csvfhandler = fopen("AlgoTest.csv", "wb");//the new lua file
if (csvfhandler == NULL)
{
fclose(csvfhandler);
printf("GUI CONNECT csv file failed to open!\n");
}
else {
SOCKET sock1 = open_socket(5555, SERVER_IP);
bool check = write_data(sock1, luafhandler);
bool check1 = write_data(sock1, pcapfhandler);
bool check2 = write_data(sock1, csvfhandler);
fclose(luafhandler);
fclose(pcapfhandler);
fclose(csvfhandler);
}

Sockets and Streams - Mixing StreamReader and BinaryReader

I'm working with a socket connection - to make things easier I get the socket's NetworkStream and wrap it up in a StreamReader which makes it easier to work with the largely textual content my socket receives from the server.
However there are times when the server sends binary information, like so:
TEXT
MORETEXT
500 BYTES OF BINARY DATA FOLLOWS THIS LINE
{500 bytes of binary data}
I'm reading the text content with the StreamReader fine, but because the StreamReader has its own buffer it means the StreamReader grabs the binary data before I can switch to the BinaryReader to read the 500 bytes of binary data.
Is there a way around this? I'd like the ability to read the textual data whilst still being able to read binary data.

I should do my research better; it turns out that the BinaryReader class already contains string and character processing methods (though it needs a few, like ReadLine, which can easily be added by subclassing it).
It's strange then, why BinaryReader doesn't subclass TextReader as it is more than capable of.

Here's an extension of BinaryReader that you can use to perform ReadLine and the usual BinaryReader stuff.
public class LineReader : BinaryReader
{
private Encoding _encoding;
private Decoder _decoder;
const int bufferSize = 1024;
private char[] _LineBuffer = new char[bufferSize];
public LineReader(Stream stream, int bufferSize, Encoding encoding)
: base(stream, encoding)
{
this._encoding = encoding;
this._decoder = encoding.GetDecoder();
}
public string ReadLine()
{
int pos = 0;
char[] buf = new char[2];
StringBuilder stringBuffer = null;
bool lineEndFound = false;
while(base.Read(buf, 0, 2) > 0)
{
if (buf[1] == '\r')
{
// grab buf[0]
this._LineBuffer[pos++] = buf[0];
// get the '\n'
char ch = base.ReadChar();
Debug.Assert(ch == '\n');
lineEndFound = true;
}
else if (buf[0] == '\r')
{
lineEndFound = true;
}
else
{
this._LineBuffer[pos] = buf[0];
this._LineBuffer[pos+1] = buf[1];
pos += 2;
if (pos >= bufferSize)
{
stringBuffer = new StringBuilder(bufferSize + 80);
stringBuffer.Append(this._LineBuffer, 0, bufferSize);
pos = 0;
}
}
if (lineEndFound)
{
if (stringBuffer == null)
{
if (pos > 0)
return new string(this._LineBuffer, 0, pos);
else
return string.Empty;
}
else
{
if (pos > 0)
stringBuffer.Append(this._LineBuffer, 0, pos);
return stringBuffer.ToString();
}
}
}
if (stringBuffer != null)
{
if (pos > 0)
stringBuffer.Append(this._LineBuffer, 0, pos);
return stringBuffer.ToString();
}
else
{
if (pos > 0)
return new string(this._LineBuffer, 0, pos);
else
return null;
}
}
}

sending binary files through TCP sockets c

I made a client & server that establishes a TCP connection through sockets, I'm trying to send binary data over the socket but I could only send txt or pdf files, I had no luck with exe files, I use fread and fseek to read the file and split it into a buffer. When I read the whole exe file it gets sent successfully but when I split it, it gets sent corrupted!
I read some books about sockets but I still don't know much and I have some questions.
is it okay to send the whole file in one send()?? or I should continue with sending it in small chunks?
Also, why exe files get corrupted when I send them in chunks?
Thank you!
Client Code (in c):
int bufSize = 10000;
int sentBytes = 0;
FILE * pFile;
long remainingBytes;
char * buffer;
size_t result;
pFile = fopen ( "D:\\file.exe" , "rb" );
fseek (pFile , 0 , SEEK_END);
remainingBytes = ftell (pFile);
rewind (pFile);
int bufferSize = remainingBytes > bufSize ? bufSize : remainingBytes;
buffer = (char*) malloc (sizeof(char)*bufferSize);
send(Socket, (char*)&remainingBytes, 4, 0);
while(remainingBytes > 0)
{
fseek (pFile , sentBytes , SEEK_SET);
result = fread(buffer,1,bufferSize,pFile);
if(bufferSize < remainingBytes)
{
send(Socket, buffer, bufferSize, 0);
}
else
{
send(Socket, buffer, remainingBytes, 0);
bufferSize = remainingBytes;
}
remainingBytes -= bufferSize;
sentBytes += bufferSize;
}
Server code (in c#)
try
{
int bufferSize = 200;
int len = 0;
int receivedBytes = 0;
int remainingBytes = len;
byte[] length = new byte[4];
//byte[] imgBuf = new byte[bufferSize];
int current = 0;
List<byte[]> coming = new List<byte[]>();
sockets[number].Receive(length,4,0);
len = BitConverter.ToInt32(length, 0);
remainingBytes = len;
bufferSize = len < bufferSize ? len : bufferSize;
while(receivedBytes < len)
{
if (remainingBytes > bufferSize)
{
coming.Add(new byte[bufferSize]);
//imgBuf = new byte[bufferSize];
sockets[number].Receive(coming[current], bufferSize, 0);
}
else
{
coming.Add(new byte[remainingBytes]);
//imgBuf = new byte[remainingBytes];
sockets[number].Receive(coming[current], remainingBytes, 0);
bufferSize = remainingBytes;
}
remainingBytes -= bufferSize;
receivedBytes += bufferSize;
current++;
//Array.Clear(imgBuf, 0, imgBuf.Length);
}
using (var stream = new FileStream(#"C:\receivedFile.exe",FileMode.Create))
{
using (var binaryWriter = new BinaryWriter(stream))
{
foreach (byte[] buffer in coming)
{
binaryWriter.Write(buffer);
}
}
}
}
catch (Exception ex)
{ this.setText(ex.Message, textBox2); }
Edit: Thanks for the help, I got it working :)
try
{
int bufferSize = 1024 * 100;
int len = 0;
int receivedBytes = 0;
int remainingBytes = len;
int reached = 0;
byte[] length = new byte[4];
byte[] imgBuf = new byte[bufferSize];
int current = 0;
sockets[number].Receive(length,4,0);
len = BitConverter.ToInt32(length, 0);
remainingBytes = len;
bufferSize = len < bufferSize ? len : bufferSize;
imgBuf = new byte[len];
while (reached < len)
{
reached += sockets[number].Receive(imgBuf, receivedBytes, remainingBytes, 0);
remainingBytes = len - reached;
receivedBytes = reached;
current++;
//Array.Clear(imgBuf, 0, imgBuf.Length);
}
using (var stream = new FileStream(#"C:\putty.exe",FileMode.Create))
{
using (var binaryWriter = new BinaryWriter(stream))
{
binaryWriter.Write(imgBuf);
}
}
Array.Clear(imgBuf, 0, imgBuf.Length);
}
catch (Exception ex)
{ this.setText(ex.Message, textBox2); }

You don't check how many bytes you actually received in sockets[number].Receive(coming[current], bufferSize, 0); . It doesn't have to be equal to the buffer size you have declared.
Additionaly, as said in comments, keeping whole file in memory is not a good idea.

In addition to checking the number of bytes received, you need to check the number of bytes sent by each send call -- if your TCP transmit window fills up, a send call might send less data than you requested, in which case the you'll need to resend the unsent data.
In general, you ALWAYS need to check the return value of your system calls to check for the all the various odd corner cases that can occur. Read the man pages for send(2) and recv(2) for a full list of everything that can happen.

How to split a large file into chunks in c#?

I'm making a simple file transfer sender and receiver app through the wire. What I have so far is that the sender converts the file into a byte array and sends chunks of that array to the receiver.
This works with file of up to 256mb, but this line throws a "System out of memory" exception for anything above:
byte[] buffer = StreamFile(fileName); //This is where I convert the file
I'm looking for a way to read the file in chunks then write that chunk instead of loading the whole file into a byte. How can I do this with a FileStream?
EDIT:
Sorry, heres my crappy code so far:
private void btnSend(object sender, EventArgs e)
{
Socket clientSock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
byte[] fileName = Encoding.UTF8.GetBytes(fName); //file name
byte[] fileData = null;
try
{
fileData = StreamFile(textBox1.Text); //file
}
catch (OutOfMemoryException ex)
{
MessageBox.Show("Out of memory");
return;
}
byte[] fileNameLen = BitConverter.GetBytes(fileName.Length); //length of file name
clientData = new byte[4 + fileName.Length + fileData.Length];
fileNameLen.CopyTo(clientData, 0);
fileName.CopyTo(clientData, 4);
fileData.CopyTo(clientData, 4 + fileName.Length);
clientSock.Connect("172.16.12.91", 9050);
clientSock.Send(clientData, 0, 4 + fileName.Length, SocketFlags.None);
for (int i = 4 + fileName.Length; i < clientData.Length; i++)
{
clientSock.Send(clientData, i, 1 , SocketFlags.None);
}
clientSock.Close();
}
And here's how I receive (the code was from a tutorial)
public void ReadCallback(IAsyncResult ar)
{
int fileNameLen = 1;
String content = String.Empty;
StateObject state = (StateObject)ar.AsyncState;
Socket handler = state.workSocket;
int bytesRead = handler.EndReceive(ar);
if (bytesRead > 0)
{
if (flag == 0)
{
Thread.Sleep(1000);
fileNameLen = BitConverter.ToInt32(state.buffer, 0);
string fileName = Encoding.UTF8.GetString(state.buffer, 4, fileNameLen);
receivedPath = fileName;
flag++;
}
if (flag >= 1)
{
BinaryWriter writer = new BinaryWriter(File.Open(receivedPath, FileMode.Append));
if (flag == 1)
{
writer.Write(state.buffer, 4 + fileNameLen, bytesRead - (4 + fileNameLen));
flag++;
}
else
writer.Write(state.buffer, 0, bytesRead);
writer.Close();
handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), state);
}
}
else
{
Invoke(new MyDelegate(LabelWriter));
}
}
I just really want to know how I can read the file in chunks so that I dont need to convert it to a byte.
Thanks for the responses so far, I think I'm starting to get it :D

Just call Read repeatedly with a small buffer (I tend to use something like 16K). Note that the call to Read may end up reading a smaller amount than you request. If you're using a fixed chunk size and need the whole chunk in memory, you could just use an array of that size of course.
Without knowing how you're sending the file, it's hard to give much advice about how to structure your code, but it could be something like this:
byte[] chunk = new byte[MaxChunkSize];
while (true)
{
int index = 0;
// There are various different ways of structuring this bit of code.
// Fundamentally we're trying to keep reading in to our chunk until
// either we reach the end of the stream, or we've read everything we need.
while (index < chunk.Length)
{
int bytesRead = stream.Read(chunk, index, chunk.Length - index);
if (bytesRead == 0)
{
break;
}
index += bytesRead;
}
if (index != 0) // Our previous chunk may have been the last one
{
SendChunk(chunk, index); // index is the number of bytes in the chunk
}
if (index != chunk.Length) // We didn't read a full chunk: we're done
{
return;
}
}
If I was more awake I'd probably find a more readable way of writing this, but it'll do for now. One option is to extract another method from the middle section:
// Attempts to read an entire chunk into the given array; returns the size of
// chunk actually read.
int ReadChunk(Stream stream, byte[] chunk)
{
int index = 0;
while (index < chunk.Length)
{
int bytesRead = stream.Read(chunk, index, chunk.Length - index);
if (bytesRead == 0)
{
break;
}
index += bytesRead;
}
return index;
}

var b = new byte[1<<15]; // 32k
while((count = inStream.Read(b, 0, b.Length)) > 0)
{
outStream.Write(b, 0, count);
}

public static IEnumerable<byte[]> SplitStreamIntoChunks(Stream stream, int chunkSize)
{
var bytesRemaining = stream.Length;
while (bytesRemaining > 0)
{
var size = Math.Min((int) bytesRemaining, chunkSize);
var buffer = new byte[size];
var bytesRead = stream.Read(buffer, 0, size);
if (bytesRead <= 0)
break;
yield return buffer;
bytesRemaining -= bytesRead;
}
}