libcurl-“curl\u easy\u cleanup()”导致malloc错误(C++)

当运行我的代码(粘贴在下面的相关部分)时,我会定期出现以下错误:

程序(34010,0x70000e58b000)malloc:**对象错误 0x7fc43d93fcf0:未为被释放的指针分配设置断点 在malloc\u error\u中断到调试信号:SIGABRT(信号SIGABRT)

我正在Macbook(OS-10.13)上运行多线程C++代码,其中不同的线程同时使用所讨论的代码。据我所知,libcurl确实是线程安全的,只要我不使用相同的“curl句柄”(我理解为“curl”的一个实例,即“curl*curl=curl\u easy\u init();”)同时在两个不同的线程中。在我的例子中,由于每个线程分别调用函数并初始化CURL对象的新实例,所以我应该是“安全的”,对吗?希望我遗漏了一些明显的东西,导致我(在本例中是lib curl)尝试释放已经释放的内存。如果有任何更多我应该包括的信息(以下),请不要犹豫,让我知道。

seg故障的功能是

字符串http\u lib::make\u get\u请求(字符串url)

在上面写着

curl\u easy\u cleanup(curl);

有时(不太经常)在读

res=curl\u easy\u perform(curl);

以下是我认为与我的代码相关的部分:

size_t http_lib::CurlWrite_CallbackFunc_StdString(void *contents, size_t size, size_t nmemb, std::string *s)
{
    size_t newLength = size*nmemb;
    size_t oldLength = s->size();
    try
    {
        s->resize(oldLength + newLength);
    }
    catch(std::bad_alloc &e)
    {
        //handle memory problem
        return 0;
    }

    std::copy((char*)contents,(char*)contents+newLength,s->begin()+oldLength);
    return size*nmemb;
}

string http_lib::make_post_request(string url, vector<string> headers, string post_params) {
    CURL *curl;
    CURLcode res;

    curl = curl_easy_init();
    string s;
    if(curl)
    {
        struct curl_slist *chunk = NULL;

        for(int i=0; i<headers.size(); i++){
            /* Add a custom header */
            chunk = curl_slist_append(chunk, headers[i].c_str());
        }

        /* set our custom set of headers */
        res = curl_easy_setopt(curl, CURLOPT_HTTPHEADER, chunk);
        curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
        curl_easy_setopt(curl, CURLOPT_POSTFIELDS, post_params.c_str());
        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L); //only for https
        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L); //only for https
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, CurlWrite_CallbackFunc_StdString);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &s);
        if(networking_debug){
            curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L); //verbose output
        }

        /* Perform the request, res will get the return code */
        res = curl_easy_perform(curl);

        /* Check for errors */
        if(res != CURLE_OK)
        {
            fprintf(stderr, "curl_easy_perform() failed: %s\n",
                    curl_easy_strerror(res));
        }

        /* always cleanup */
        curl_easy_cleanup(curl);
    }

    // Debug output
    if (networking_debug){
        cout<<"Response: " << s <<endl;
    }

    return s;
}

string http_lib::make_get_request(string url) {
    //SslCurlWrapper sslObject;
    CURL *curl;
    CURLcode res;

    curl = curl_easy_init();
    string s;
    if (curl) {
        curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
        //tell libcurl to follow redirection
        curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L); //only for https
        curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L); //only for https
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, CurlWrite_CallbackFunc_StdString);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &s);
        if(networking_debug){
            curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L); //verbose output
        }

        /* Perform the request, res will get the return code */
        res = curl_easy_perform(curl);
        /* Check for errors */
        if (res != CURLE_OK)
            fprintf(stderr, "curl_easy_perform() failed: %s\n", curl_easy_strerror(res));

        /* always cleanup */
        curl_easy_cleanup(curl);
    }

    if (networking_debug){
        cout << "Response: " << s << endl;
    }

    return s;
}

在main()中,我有

int main(int argc, char *argv[]){
    // Initialize http_lib (curl)
    curl_global_init(CURL_GLOBAL_DEFAULT);

    ... spin up 10 or so threads that make get/post requests to https site (some requests utilize the make_post_request() function and others utilize make_get_requet() function). 
}