Question

我正在开发一个简单的基于moongose的Web服务器，无论请求是什么，都会通过HTTP发送作为参数传递的文件，但是在每个请求中我都会收到堆栈溢出错误。

这是我的代码：

#include <stdio.h>
#include <string.h>
#include "mongoose.h"

// file path
char *path;

static void *callback(enum mg_event event, struct mg_connection *conn) 
{
    const struct mg_request_info *request_info = mg_get_request_info(conn);
    mg_send_file(conn, path);

    return "";
}

int main(int argc,char *argv[]) 
{    
    struct mg_context *ctx;
    const char *options[] = {"listening_ports", "8081", NULL};

    // registers file
    path = argv[1];
    ctx = mg_start(&callback, NULL, options);
    printf("%s", path);
    getchar();  // Wait until user hits "enter"
    mg_stop(ctx);

    return 0;
}

我正在使用visual studio 2010来构建项目

有没有人知道可能导致此错误的原因？

Answer 1

您没有为回调函数指定任何返回值，根据定义，该函数是未定义的行为。检查回调的正确返回结果要求，因为void *不是void的同义词。我很确定返回值是回调事件依赖，但不要引用我。（该死...太晚了。）

取自mongoose标题（至少我有权访问的版本），描述提供给mg_start()的回调函数的目的和职责：

// Prototype for the user-defined function. Mongoose calls this function
// on every event mentioned above.
//
// Parameters:
//   event: which event has been triggered.
//   conn: opaque connection handler. Could be used to read, write data to the
//         client, etc. See functions below that accept "mg_connection *".
//   request_info: Information about HTTP request.
//
// Return:
//   If handler returns non-NULL, that means that handler has processed the
//   request by sending appropriate HTTP reply to the client. Mongoose treats
//   the request as served.
//   If callback returns NULL, that means that callback has not processed
//   the request. Handler must not send any data to the client in this case.
//   Mongoose proceeds with request handling as if nothing happened.

typedef void * (*mg_callback_t)(enum mg_event event,
                   struct mg_connection *conn,
                   const struct mg_request_info *request_info);

Answer 2

确保“path”不为NULL。分配默认值。

每个请求都会在mongoose中堆栈溢出

2 个答案: