編輯的代碼有問題

Question

問了一個問題Call CloseHandle on handle that is a function parameter?

人編輯的代碼後，我更新了它發現代碼不再按預期工作。

intptr_t readMem(HANDLE processHandle, intptr_t address, int sizeToReadBytes) 
{ 
    intptr_t memValue = 0; 

    bool success = ReadProcessMemory(processHandle, (LPVOID)address, memValue, sizeToReadBytes, NULL); 
    if (!success) 
     std::wcout << "Memory read failed on address: " << std::hex << address << "\n"; 

    return memValue; 
} 

在線路

ReadProcessMemory(processHandle, (LPVOID)address, memValue, sizeToReadBytes, NULL); 

的memValue不會沒有(LPVOID)或(LPCVOID)石膏編譯，但是與它們的代碼不再讀取存儲器（或在的情況下，寫入使用的功能WriteProcessMemory

最初（現在我已經改變了它在我的小程序中）它使用參考&memValue和工作正常。我的問題是：

應該這樣工作嗎？ 或者是編輯正確，我的程序的其餘部分可能是錯誤的？

如果需要，我可以提供更多的代碼，只是不知道哪些位，並不想堵塞屏幕比我更...還應該回滾編輯？

Answer 1

ReadProcessMemory()的第三個參數是函數將讀取數據寫入的調用過程中的內存地址。雖然你沒有傳遞內存地址。在原始問題的第三個修訂版本中顯示的代碼中，您將未初始化的整數變量的值鍵入到內存指針中。所以函數會嘗試寫入隨機存儲器。現在你已經刪除了類型轉換，所以代碼甚至不應該再編譯了。您的readMem()功能設計不正確。你需要這樣或者改變它：

1. 呼叫者分配所需大小的存儲器中，然後該函數簡單地填充內存：

   bool readMem(HANDLE processHandle, intptr_t address, void *memValue, int sizeToReadBytes) 
   { 
       bool success = ReadProcessMemory(processHandle, (LPVOID)address, memValue, sizeToReadBytes, NULL); 
       if (!success) 
       std::wcout << "Memory read failed on address: " << std::hex << address << "\n"; 
       return success; 
   } 
   

   intptr_t memValue = 0; 
   readMem(processHandle, address, &memValue, sizeof(memValue)); 
   

2. 功能分配內存並將其返回給調用者：

   void* readMem(HANDLE processHandle, intptr_t address, int sizeToReadBytes) 
   { 
       uint8_t memValue = new uint8_t[sizeToReadBytes]; 
       bool success = ReadProcessMemory(processHandle, (LPVOID)address, memValue, sizeToReadBytes, NULL); 
       if (!success) { 
       std::wcout << "Memory read failed on address: " << std::hex << address << "\n"; 
       delete [] memValue; 
       memValue = NULL; 
       } 
       return memValue; 
   } 
   

   intptr_t *memValue = (intptr_t*) readMem(processHandle, address, sizeof(intptr_t)); 
   ... 
   delete [] memValue; 
   

   或者：

   bool readMem(HANDLE processHandle, intptr_t address, int sizeToReadBytes, std:vector<uint8_t> &memValue) 
   { 
       memValue.resize(sizeToReadBytes); 
       bool success = ReadProcessMemory(processHandle, (LPVOID)address, &memValue[0], sizeToReadBytes, NULL); 
       if (!success) 
       std::wcout << "Memory read failed on address: " << std::hex << address << "\n"; 
       return success; 
   } 
   

   std::vector<uint8_t> buffer; 
   readMem(processHandle, address, sizeof(intptr_t), buffer); 
   intptr_t memValue = (intptr_t*) &buffer[0];