我正在尝试将文件发布到API,然后检查响应中的各种情况。但是,每当我尝试发布大于0字节的文件时,都会出现错误:

First-chance exception at 0x77AADF63 (ntdll.dll) in Test.exe:
0xC0000005: Access violation writing location 0x00000014.

相关代码为:
std::string Network::Post(std::string url, std::map<std::string, std::string> requestBody, std::string file, int port) {
    std::ostringstream response;

    std::stringstream bodyStream;
    struct stat file_info;


    for (std::map<std::string, std::string>::iterator iterator = requestBody.begin(); iterator != requestBody.end(); iterator++) {
        bodyStream << iterator->first << "=" << iterator->second << "&";
    }

    //Get file
    FILE* file_handle = fopen(file.c_str(), "rb");
    int t = fstat(_fileno(file_handle), &file_info);

    CURL *ch;
    curl_global_init(CURL_GLOBAL_ALL);
    ch = curl_easy_init();

    struct curl_slist *headers = NULL;

    curl_slist_append(headers, "Content-Type: application/x-www-form-urlencoded");

    std::string bodyStreamString = bodyStream.str();
    const char* bodyStreamCharPtr = bodyStreamString.c_str();

    curl_easy_setopt(ch, CURLOPT_URL, url.c_str());
    curl_easy_setopt(ch, CURLOPT_PORT, port);
    curl_easy_setopt(ch, CURLOPT_POSTFIELDS, bodyStreamCharPtr);
    curl_easy_setopt(ch, CURLOPT_POSTFIELDSIZE, bodyStream.str().length());
    curl_easy_setopt(ch, CURLOPT_HTTPHEADER, headers);
    curl_easy_setopt(ch, CURLOPT_AUTOREFERER, 1);
    curl_easy_setopt(ch, CURLOPT_FOLLOWLOCATION, 1);
    curl_easy_setopt(ch, CURLOPT_COOKIEFILE, "cookies.dat");
    curl_easy_setopt(ch, CURLOPT_COOKIEJAR, "cookies.dat");
    curl_easy_setopt(ch, CURLOPT_WRITEFUNCTION, &ResponseToString);
    curl_easy_setopt(ch, CURLOPT_VERBOSE, 1L);
    curl_easy_setopt(ch, CURLOPT_UPLOAD, 1L);
    curl_easy_setopt(ch, CURLOPT_READDATA, file_handle);
    curl_easy_setopt(ch, CURLOPT_INFILESIZE_LARGE, (curl_off_t)file_info.st_size);
    curl_easy_setopt(ch, CURLOPT_WRITEDATA, &response);

    int res = curl_easy_perform(ch);
    curl_easy_cleanup(ch);

    return response.str();
}


size_t Network::ResponseToString(char *ptr, size_t size, size_t nmemb, void *stream) {
    std::ostringstream *s = (std::ostringstream*)stream;
    size_t count = size * nmemb;
    s->write(ptr, count);
    return count;
}

知道发生了什么吗?坚持了一天左右,叹了口气:(

更多细节:

它只是在“int res = curl_easy_perform(ch);”处中断。 ,无法介入。

如果我删除了WRITEFUNCTION和WRITEDATA选项,它可以工作,但无法获得响应。

这个问题似乎也不在ResponseToString方法中。

最佳答案

问题是您的WRITEFUNC。

我非常确定Network::ResponseToString不是静态的,这会引起问题,因为非静态函数会将“this”作为第一个参数传递,然后拧入函数参数,因此我建议完全避免使用类成员,并且使用它(与Network::Post放在同一文件中,并在Post方法定义之前):

static size_t ResponseToString(char *ptr, size_t size, size_t nmemb, std::ostringstream *stream) {
    size_t count = size * nmemb;
    stream->write(ptr, count);
    return count;
}

记住也要更改:
curl_easy_setopt(ch, CURLOPT_WRITEFUNCTION, &ResponseToString);

在:
curl_easy_setopt(ch, CURLOPT_WRITEFUNCTION, ResponseToString);

另外,如果您的作用域是一个简单的“post”,则不需要在curl opt声明中指定的许多 header :
curl_easy_setopt(ch, CURLOPT_POSTFIELDSIZE, bodyStream.str().length());
curl_easy_setopt(ch, CURLOPT_UPLOAD, 1L);
curl_easy_setopt(ch, CURLOPT_READDATA, file_handle);
curl_easy_setopt(ch, CURLOPT_INFILESIZE_LARGE, (curl_off_t)file_info.st_size);

关于c++ - C++ CURL发布文件,然后得到响应错误,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/32244887/

10-13 08:34
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