ReadProcessMemory() 返回 0 ERROR_PARTIAL_COPY

Question

#include <Windows.h>
#include <iostream>
#include <vector>
#include <TlHelp32.h>
#include <tchar.h>

using namespace std;

DWORD GetModuleBase(LPSTR lpModuleName, DWORD dwProcessId)
{
   MODULEENTRY32 lpModuleEntry = {0};
   HANDLE hSnapShot = CreateToolhelp32Snapshot( TH32CS_SNAPMODULE, dwProcessId );

   if(!hSnapShot)
      return NULL;
   lpModuleEntry.dwSize = sizeof(lpModuleEntry);
   BOOL bModule = Module32First( hSnapShot, &lpModuleEntry );
   while(bModule)
   {
      if(!strcmp( lpModuleEntry.szModule, lpModuleName ) )
      {
         CloseHandle( hSnapShot );
         return (DWORDLONG)lpModuleEntry.modBaseAddr;
      }
      bModule = Module32Next( hSnapShot, &lpModuleEntry );
   }
   CloseHandle( hSnapShot );
   return NULL;
}


int main() {
    DWORD pID;
    DWORDLONG off1, off2;
    DWORDLONG baseAddress;
    char moduleName[] = _T("AoE2DE_s.exe");
    HWND hGameWindow;
    HANDLE pHandle;

    //Get Handles
    hGameWindow = FindWindow(NULL, "Age of Empires II: Definitive Edition");
    cout << "Game Window: " << hGameWindow << std::endl;
    GetWindowThreadProcessId(hGameWindow, &pID);
    cout << "Process ID: " << pID << std::endl;
    pHandle = OpenProcess(PROCESS_ALL_ACCESS, FALSE, pID);

    cout << "Process Handle: " << std::hex << pHandle << std::endl;

    //Get Client Base Addy
    DWORDLONG clientBase = GetModuleBase(moduleName, pID);
    cout << "Client Base: " << clientBase << std::endl;
    ReadProcessMemory(pHandle, (LPCVOID)(clientBase + 0x2BFCA18), &baseAddress, sizeof(DWORDLONG), NULL);
    DWORD lastError = GetLastError();
    cout << "Error: " << lastError << std::endl;
    cout << "Base Address: " << std::hex << baseAddress << std::endl;
    ReadProcessMemory(pHandle, (LPCVOID)(baseAddress + 0x18), &off1, sizeof(DWORDLONG), NULL);
    cout << "After Offset 1: " << std::hex << off1 << std::endl;
    ReadProcessMemory(pHandle, (LPCVOID)(off1 + 0x9230), &off2, sizeof(DWORDLONG), NULL);
    cout << "After Final Offset: " << off2 << std::endl;
    cin.get();
}

错误发生在这一行： ReadProcessMemory(pHandle, (LPCVOID)(clientBase + 0x2BFCA18), &baseAddress, sizeof(DWORDLONG), NULL);

用于调试目的的应用程序输出：

Game Window: 0x1307c2
Process ID: 11988
Process Handle: 0xec
Client Base: cc640000
Error: 12b
Base Address: 0
After Offset 1: 401519
After Final Offset: 8

不确定它是如何失败的，我对此有些陌生。如果有人可以帮助解决这个问题，我将不胜感激。

Answer 1

ReadProcessMemory 是这样定义的：

BOOL ReadProcessMemory(
  HANDLE  hProcess,
  LPCVOID lpBaseAddress,
  LPVOID  lpBuffer,
  SIZE_T  nSize,
  SIZE_T  *lpNumberOfBytesRead
);

如果它返回零，则说明有错误，只有在这种情况下，GetLastError 才会返回一个有意义的错误号。

所以正确的用法是：

SIZE_T readBytes;
if (!ReadProcessMemory(pHandle, (LPCVOID)(clientBase + 0x2BFCA18), &baseAddress, sizeof(DWORDLONG), &readBytes)) {
  DWORD lastError = GetLastError();
  cout << "ReadProcessMemory failed: Error: " << lastError << " read " << readBytes << std::endl;
}
else
{
  cout << "ReadProcessMemory succeeded"; << std::endl;
  cout << "Base Address: " << std::hex << baseAddress << std::endl;
}