[C/C++] CoD5WaW Multiplayer Patch

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <string.h>
#include <windows.h>
#include <tlhelp32.h>

#define PROCESS "CoDWaWmp.exe"

/*
CoDWaWmp.exe international v1.7

0049E992 /75 2C JNZ SHORT CoDWaWmp.0049E9C0 <---
0049E994 |E8 47C71700 CALL CoDWaWmp.0061B0E0
0049E999 |83F8 04 CMP EAX,4
0049E99C |74 22 JE SHORT CoDWaWmp.0049E9C0
0049E99E |68 98EB8300 PUSH CoDWaWmp.0083EB98
0049E9A3 |6A 40 PUSH 40
0049E9A5 |B0 01 MOV AL,1
0049E9A7 |BF 0C9E8500 MOV EDI,CoDWaWmp.00859E0C ; ASCII "dw_connectafterlogin"
*/
#define PATCH_ADD_INT 0x0049E992
#define PATCH_ADD_DE 0x0049E812
#define MAGIC_BYTE 0x75



DWORD getProcessByName(char * processName);
bool patchMemory( DWORD pid, DWORD address, BYTE byteReplace );
bool checkGameVersion(DWORD pid);

int main(int argc, char *argv[])
{
 bool unpatched = true;
 bool internationalVersion = false;

 printf("CoD 5 WaW Multiplayer Patch\n\n");
 while (1)
 {
 //patch
 if(unpatched || ((GetAsyncKeyState(VK_F1)&1)==1))
 {
 DWORD pid = getProcessByName(PROCESS);
 if (pid != 0) 
 {
 unpatched = false;
 if(checkGameVersion(pid))
 {
 internationalVersion = true;
 if(patchMemory(pid,PATCH_ADD_INT,0xEB))
 {
 printf("Patch successfull\n");
 } else {
 printf("Error patch\n");
 }
 } else {
 if(patchMemory(pid,PATCH_ADD_DE,0xEB))
 {
 printf("Patch successfull\n");
 unpatched = false;
 } else {
 printf("Error patch\n");
 }
 }
 }
 }
 //unpatch
 if ((GetAsyncKeyState(VK_F2)&1)==1)
 {
 DWORD pid = getProcessByName(PROCESS);
 if (pid != 0) 
 {
 if(internationalVersion)
 {
 if(patchMemory(pid,PATCH_ADD_INT,0x75))
 {
 printf("Patch removed\n");
 } else {
 printf("Error unpatch\n");
 }
 } else {
 if(patchMemory(pid,PATCH_ADD_DE,0x75))
 {
 printf("Patch removed\n");
 } else {
 printf("Error unpatch\n");
 }
 }
 }
 }
 //exit
 if ((GetAsyncKeyState(VK_F3)&1)==1)
 {
 break;
 }
 Sleep(200);
 }

 return 0;
}

bool patchMemory( DWORD pid, DWORD address, BYTE byteReplace ) 
{
 DWORD rBuf = 0;
 HANDLE hProcess = OpenProcess(PROCESS_VM_WRITE|PROCESS_VM_OPERATION, NULL, pid);
 if(!hProcess) {
 printf("Error OpenProcess %u\n",GetLastError());
 return 0;
 }
 BOOL wpmRet = WriteProcessMemory(hProcess,(LPVOID)address,&byteReplace,1,&rBuf);
 if (!wpmRet) {
 printf("Error WriteProcessMemory %u\n",GetLastError());
 return 0;
 }

 CloseHandle(hProcess);

 if (rBuf == 1)
 {
 return true;
 } else {
 return false;
 }
}

bool checkGameVersion(DWORD pid)
{
 DWORD rBuf = 0;
 DWORD buff = 0;

 HANDLE hProcess = OpenProcess(PROCESS_VM_READ, NULL, pid);
 if(!hProcess) {
 printf("Error OpenProcess %u\n",GetLastError());
 return 0;
 }

 BOOL rpmRet = ReadProcessMemory(hProcess,(LPCVOID)PATCH_ADD_INT,&buff,1,&rBuf);
 if (!rpmRet) {
 printf("Error ReadProcessMemory %u\n",GetLastError());
 return 0;
 }
 CloseHandle(hProcess);

 if (rBuf == 1)
 {
 if (buff == MAGIC_BYTE)
 {
 printf("Detected international version\n");
 return true;
 } else {
 printf("Detected german version\n");
 return false;
 }
 } else {
 return false;
 }
}

DWORD getProcessByName(char * processName)
{
 HANDLE hProcessSnap = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
 PROCESSENTRY32 pe32;
 pe32.dwSize = sizeof(PROCESSENTRY32);

 if( !Process32First( hProcessSnap, &pe32 ) )
 {
 printf("Error getting Process\n");
 CloseHandle( hProcessSnap );
 return 0;
 }

 do
 {
 if(!_stricmp(pe32.szExeFile, processName)) 
 {
 CloseHandle(hProcessSnap);
 return pe32.th32ProcessID;
 }
 } while(Process32Next(hProcessSnap, &pe32));

 CloseHandle(hProcessSnap);
 return 0;
}