Unexplainable problem

[bmw]

I am trying to compare 2 char arrays with strcmp.

The two char arrays are both exactly the same ([e], [x], [i], [t], [0])

I am trying to send an exit command to my server.

However, strcmp will not return 0.

Code: (the strcmp is in the process() function at the bottom)

#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif

#include <Windows.h>
#include <string.h>
#include <WinSock2.h>
#include <WS2tcpip.h>
#include <iostream>

#pragma comment(lib, "Ws2_32.lib")

#define PORT "1231"
#define DEFAULT_BUFLEN 512

SOCKET ListenSocket;
SOCKET ClientSocket;

void process(const char* data);

int main()
{
	WSADATA wsaData;

	int iResult = 0;

	iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);

	if(iResult != 0)
	{
		std::cout << "WSAStartup failed.\n";
		system("pause");
		return 1;
	}

	while(1)
	{

		struct addrinfo hints, *result;

		ZeroMemory(&hints, sizeof(hints));

		hints.ai_family = AF_INET;
		hints.ai_socktype = SOCK_STREAM;
		hints.ai_protocol = IPPROTO_TCP;
		hints.ai_flags = AI_PASSIVE;

		iResult = getaddrinfo(NULL, PORT, &hints, &result);

		if(iResult != 0)
		{
			std::cout << "getaddrinfo failed.\n";
			WSACleanup();
			system("pause");
			return 1;
		}

		ListenSocket = INVALID_SOCKET;

		ListenSocket = socket(result->ai_family, result->ai_socktype, result->ai_protocol);

		if(ListenSocket == INVALID_SOCKET)
		{
			std::cout << "socket failed.\n";
			freeaddrinfo(result);
			WSACleanup();
			system("pause");
			return 1;
		}

		((sockaddr_in*)result->ai_addr)->sin_addr.S_un.S_addr = inet_addr("10.1.1.3");

		iResult = bind(ListenSocket, result->ai_addr, (int)result->ai_addrlen);

		if(iResult == SOCKET_ERROR)
		{
			std::cout << "bind failed.\n";
			closesocket(ListenSocket);
			freeaddrinfo(result);
			WSACleanup();
			system("pause");
			return 1;
		}

		freeaddrinfo(result);

		if(listen(ListenSocket, 1) == SOCKET_ERROR)
		{
			std::cout << "listen failed.\n";
			closesocket(ListenSocket);
			WSACleanup();
			system("pause");
			return 1;
		}

		ClientSocket = INVALID_SOCKET;

		ClientSocket = accept(ListenSocket, NULL, NULL);

		if(ClientSocket == INVALID_SOCKET)
		{
			std::cout << "accept failed.\n";
			closesocket(ListenSocket);
			WSACleanup();
			system("pause");
			return 1;
		}

		char recvbuf[DEFAULT_BUFLEN];
		int iSendResult;
		int recvbuflen = DEFAULT_BUFLEN;

		char DataReceived[DEFAULT_BUFLEN * 2] = {NULL};
		unsigned int c = 0;

		// Receive until the peer shuts down the connection
		do {

			iResult = recv(ClientSocket, recvbuf, recvbuflen, 0);
			if (iResult > 0)
			{
				//Do something with data received
				for(int i = 0; i < iResult; i++)
				{
					if(recvbuf[i] == '\n')
					{
						DataReceived[c] = 0;
						process(DataReceived);
						c = 0;
						continue;
					}
					DataReceived[c] = recvbuf[i];
					c++;
				}

			}
			else if (iResult == 0)
				printf("Connection closed.\n");
			else
			{
				printf("recv failed: %d\n", WSAGetLastError());
				closesocket(ClientSocket);
				closesocket(ListenSocket);
				WSACleanup();
				return 1;
			}

		} while (iResult > 0);

		closesocket(ClientSocket);
		closesocket(ListenSocket);

	}

	WSACleanup();

	return 0;
}

void process(const char* data)
{
	const char cmd[] = {'e', 'x', 'i', 't', 0};

	if(strcmp(data, cmd) == 0)
	{
		closesocket(ListenSocket);
		closesocket(ClientSocket);
		WSACleanup();
		exit(0);
	}
}

[MiiNiPaa]

assign recvbuf value "exit\ndfhdfh\0" manually after line 119. If problem persist: you have problem with command handling. If not: you have problem with data sending and receiving.
And use a debugger to find problems more easily.

[vlad from moscow]

I am not sure but maybe each sentence in recvbuf is ended with CR + LF that is with '\r' + '\n'.

[bmw]

Ok. I realised the error of my ways.

I was using telnet to send the command to my server. Pressing enter in telnet sends \r\n so thats why it wasn't working.

Thanks for help everyone.

[tomek320]

If someone can help me i would be greatfull :) I'm dealing with animated DFS i mean i want to animate it , on some examples runs fine but on the others dont .
Here is the code :

#include <iostream>
#include <stack>
#include <windows.h>
using namespace std;
char map[5][5],render[5][5];
stack<int> s;

struct nvm { 
int rx,sx;
} st,en;

bool start=false,end = false;
int g1,g2;

int TIME = 500; //<----- VARIABLA ZA PODESAVANJE VREMENA , SVAKIH 1000 = 1 SEC, MOGUCE MJENJATI OVDJE!!

int main() {
    printf("\n");
    for(int r=0;r<5;r++) { 
       for(int s=0;s<5;s++)  {again: cin>>(map[r][s]);
                              render[r][s]=map[r][s]; 
                             if(map[r][s] == ' ') {goto again;} 
                             if((map[r][s] == 50)&&(start == false)) {st.rx = r; st.sx = s; start=true;}
                             /*printf("\nR:%d S:%d",r,s);*/}}
       
    Sleep(2000); render[st.rx][st.sx] = 'X';  Sleep(TIME); 
    s.push(st.sx); s.push(st.rx);
    
    while(end!=true)
    {
    system("CLS");
    for(int r=0;r<5;r++) { printf("\n");
       for(int s=0;s<5;s++) {printf("%c ",render[r][s]);}}
       printf("\n");
       printf("\nstart cordinates: x:%d y:%d",st.rx,st.sx);    
       
       
       
/////////////////////////////////////// LOGICKI DIO DFS-a    
//(logic part ---> that i need to fix).
     

          if ((st.sx < 4)&&(render[st.rx][st.sx+1] != 'x')&&(render[st.rx][st.sx+1] != 'X')&&(render[st.rx][st.sx+1] != '1')&&(render[st.rx][st.sx+1] != '.')/*fali dio sa velikim X*/) {if((map[st.rx][st.sx+1]== '0' || map[st.rx][st.sx+1]== '2') && (render[st.rx][st.sx+1]== '0' || render[st.rx][st.sx+1]== '2')) { render[st.rx][st.sx+1] = 'x';  st.sx++; s.push(st.sx); s.push(st.rx); if (map[st.rx][st.sx]== '2') goto fin; }}

     else if ((st.rx > 0)&&(render[st.rx-1][st.sx] != 'x')&&(render[st.rx-1][st.sx] != 'X')&&(render[st.rx-1][st.sx] != '1')&&(render[st.rx-1][st.sx] != '.')/*fali dio sa velikim X*/) {if((map[st.rx-1][st.sx]== '0' || map[st.rx-1][st.sx]== '2') && (render[st.rx-1][st.sx]== '0' || render[st.rx-1][st.sx]== '2')) { render[st.rx-1][st.sx] = 'x';  st.rx--; s.push(st.sx); s.push(st.rx); if (map[st.rx][st.sx]== '2')  goto fin; }}

     else if ((st.sx > 0)&&(render[st.rx][st.sx-1] != 'x')&&(render[st.rx][st.sx-1] != 'X')&&(render[st.rx][st.sx-1] != '1')&&(render[st.rx][st.sx-1] != '.')/*fali dio sa velikim X*/) {if((map[st.rx][st.sx-1]== '0' || map[st.rx][st.sx-1]== '2') && (render[st.rx][st.sx-1]== '0' || render[st.rx][st.sx-1]== '2')) { render[st.rx][st.sx-1] = 'x';  st.sx--; s.push(st.sx); s.push(st.rx); if (map[st.rx][st.sx]== '2')  goto fin; }}

     else if ((st.rx < 4)&&(render[st.rx+1][st.sx] != 'x')&&(render[st.rx+1][st.sx] != 'X')&&(render[st.rx+1][st.sx] != '1')&&(render[st.rx+1][st.sx] != '.')/*fali dio sa velikim X*/) {if((map[st.rx+1][st.sx]== '0' || map[st.rx+1][st.sx]== '2') && (render[st.rx+1][st.sx]== '0' || render[st.rx+1][st.sx]== '2')) { render[st.rx+1][st.sx] = 'x';  st.rx++; s.push(st.sx); s.push(st.rx); if (map[st.rx][st.sx]== '2')  goto fin; }}

   
 else if (((render[st.rx][st.sx+1]== '1')||(render[st.rx][st.sx+1]== 'x')||(render[st.rx][st.sx+1]== 'X')||(render[st.rx][st.sx+1]== '.'))&&((render[st.rx][st.sx-1]== '1')||(render[st.rx][st.sx-1]== 'x')||(render[st.rx][st.sx-1]== 'X')||(render[st.rx][st.sx-1]== '.'))&&((render[st.rx+1][st.sx]== '1')||(render[st.rx+1][st.sx]== 'x')||(render[st.rx+1][st.sx]== 'X')||(render[st.rx+1][st.sx]== '.'))&&((render[st.rx-1][st.sx]== '1')||(render[st.rx-1][st.sx]== 'x')||(render[st.rx-1][st.sx]== 'X')||(render[st.rx-1][st.sx]== '.'))) {g1 = s.top(); s.pop(); g2 = s.top(); s.pop(); render[g1][g2] = '.' ; st.rx = g1; st.sx = g2;  }// dok su svi putevi necime zablokirani    
   Sleep(TIME); 
   }
///////////////////////////////////////
    fin:
    render[st.rx][st.sx] = 'X';
    Sleep(TIME); 
    system("CLS");
    for(int r=0;r<5;r++) { printf("\n");
       for(int s=0;s<5;s++) {printf("%c ",render[r][s]);}}
       printf("\n");
       printf("\nstart cordinates: x:%d y:%d",st.rx,st.sx);


               
    Sleep(3000);
return 0 ; }

And here are the examples of matrix:

2 1 1 1 1
0 0 1 0 1
0 1 1 0 0 // runs good , but wrong animations
0 0 0 0 1
0 1 2 1 1

2 0 0 1 2
1 0 1 1 0
0 0 0 1 0 // never runs till end
1 0 1 1 0
0 0 0 0 0

0 0 2 1 2
0 0 1 0 0
0 1 0 0 1 // works perfectly :)
0 0 1 0 0
1 0 0 0 1

Plz if you can tell me what runtime error couse first two problems , please subsmit.. (i know i did so much mess in the code ).