调试错误：变量'cardDesc'周围的堆栈已损坏

Question

标题。 我正在使用的功能是这样的：

void GetVideoCardInfo(int* memoryVar, char* cardName)
{
    strcpy_s(cardName, 128, m_videoCardDescription);
    *memoryVar = m_videoCardMemory;
    return;
}

m_videoCardDescription是一个“ 128个字符长”的字符数组，其中包含我的视频卡的描述。这是我在调用函数的地方：

bool writeGPUnameDesc() {
    char cardDesc;
    int cardMem;
    m_D3D->GetVideoCardInfo(&cardMem, &cardDesc);

    std::ofstream myfile;
    myfile.open("gpuNameAndDesc.txt");
    myfile << "Graphics card name: " << cardDesc;
    myfile << " - Graphics card memory: " << cardMem;
    myfile.close();

    return true;
}

当我运行程序时，会弹出一个消息框，提示运行时检查失败＃2 和标题。如果有人可以帮助，请先感谢。

Answer 1

您要将128个字符复制到char cardDesc中，该字符仅代表1个字符。

您应将cardDesc的类型更改为字符数组：

char cardDesc[128];
// ...
m_D3D->GetVideoCardInfo(&cardMem, cardDesc);
//                                ^ no &

Answer 2

TL; DR

std::string GetVideoCardInfo(int & memoryVar)
{
    memoryVar = m_videoCardMemory;
    return m_videoCardDescription;;
}


bool writeGPUnameDesc() {
    int cardMem;
    std::string cardDesc = m_D3D->GetVideoCardInfo(cardMem); 

    std::ofstream myfile;
    myfile.open("gpuNameAndDesc.txt");
    myfile << "Graphics card name: " << cardDesc;
    myfile << " - Graphics card memory: " << cardMem;
    myfile.close();

    return true;
}

说明

strcpy_s(cardName, 128, m_videoCardDescription);

是一个公然的谎言。 cardName的大小正好是一个字符。如果您撒谎strcpy_s，则对其进行额外的检查以确保您不会超出缓冲区的范围，将无济于事。

劣等解决方案

替换

char cardDesc;   

与

char cardDesc[129]; 

更好的方法完全摆脱了magic numbers。

在文件顶部附近

namespace // annonymous namespace. Contents will not leak out of the file
{
    constexpr int MAX_CARD_NAME_LENGTH = 129 // 128 plus room for nul terminator
}

然后

void GetVideoCardInfo(int* memoryVar, char* cardName)
{
    strcpy_s(cardName, MAX_CARD_NAME_LENGTH, m_videoCardDescription);
    *memoryVar = m_videoCardMemory;
    return;
}

和

bool writeGPUnameDesc() {
    char cardDesc[MAX_CARD_NAME_LENGTH]; // now an array
    int cardMem;
    m_D3D->GetVideoCardInfo(&cardMem, cardDesc); // don't need to take address of array

    std::ofstream myfile;
    myfile.open("gpuNameAndDesc.txt");
    myfile << "Graphics card name: " << cardDesc;
    myfile << " - Graphics card memory: " << cardMem;
    myfile.close();

    return true;
}