Question

我在C ++中通过curl库上传文件时出现崩溃问题。我使用了此位置的确切演示代码：https://curl.haxx.se/libcurl/c/fileupload.html

我在代码中唯一更改的内容是上传位置，上传到Windows上的本地wamp服务器以及要上传的文件，我已经确认其开放状态正常。

我正在浏览visual studio 2014，并通过DLL构建CURL

该计划的输出是：

*   Trying 127.0.0.1...
* TCP_NODELAY set
* Connected to 127.0.0.1 (127.0.0.1) port 80 (#0)
> PUT /replayupload.php HTTP/1.1
Host: 127.0.0.1
Accept: */*
Content-Length: 43
Expect: 100-continue

< HTTP/1.1 100 Continue

*然后我在程序第66行遇到了崩溃。看来这一行：

 res = curl_easy_perform(curl);

导致参数无效的问题。我已经验证了curl变量不是null，但我发现很难获得调试信息，调用堆栈只是引用了DLL中的内存地址。

我能够运行演示只是上传帖子变量并获得一个页面，这样可以正常运行而不会崩溃。仅在上载文件时发生崩溃。

我的确切代码是：

int main(void)
{
    CURL *curl;
    CURLcode res;
    struct stat file_info;
    double speed_upload, total_time;
    FILE *fd;

    fd = fopen("E:\\testfiles\\test.txt", "rb"); /* open file to upload */
    if (!fd)
        return 1; /* can't continue */

              /* to get the file size */
    if (fstat(_fileno(fd), &file_info) != 0)
        return 1; /* can't continue */

    curl = curl_easy_init();
    if (curl) {
        /* upload to this place */
        curl_easy_setopt(curl, CURLOPT_URL,
            "http://127.0.0.1/testupload.php");

        /* tell it to "upload" to the URL */
        curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);

        /* set where to read from (on Windows you need to use READFUNCTION too) */
        curl_easy_setopt(curl, CURLOPT_READDATA, fd);

        /* and give the size of the upload (optional) */
        curl_easy_setopt(curl, CURLOPT_INFILESIZE_LARGE,
            (curl_off_t)file_info.st_size);

        /* enable verbose for easier tracing */
        curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);

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

        }
        else {
            /* now extract transfer info */
            curl_easy_getinfo(curl, CURLINFO_SPEED_UPLOAD, &speed_upload);
            curl_easy_getinfo(curl, CURLINFO_TOTAL_TIME, &total_time);

           fprintf(stderr, "Speed: %.3f bytes/sec during %.3f seconds\n",
                speed_upload, total_time);

        }
        /* always cleanup */
        curl_easy_cleanup(curl);
    }
    fclose(fd);
    return 0;
}

Answer 1

感谢Tkausl发现了这条线

/* set where to read from (on Windows you need to use READFUNCTION too) */

我将此行添加到我的代码

curl_easy_setopt(curl, CURLOPT_READFUNCTION, &fread);

现在一切似乎都有效。

在C ++中使用CURL上传文件时崩溃curl_easy_perform（）

1 个答案: