stm32+lwip(四):网页服务器测试

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系列文章：

ST官方有lwip的例程，下载地址如下：

https://www.st.com/content/st_com/en/products/embedded-software/mcus-embedded-software/stm32-embedded-software/stm32-standard-peripheral-library-expansion/stsw-stm32070.html

本文例子参考ST官方给出的例程。

一、准备

ST例程文档关于lwip的介绍如下：

由此可以看到LWIP有三种API，在本文中，使用Raw API。

HTTP协议是建立在TCP协议之上的一种应用，本文用到的TCP Raw API如下：

二、移植官方例程

官方例程在stsw-stm32070\STM32F4x7_ETH_LwIP_V1.1.1\Project\Standalone\httpserver目录下，拷贝以下文件到我们工程：

fs.c/h是文件的操作

fs.data.c/h存放了网页的数据

httpd.c/h是网页服务器

httpd_cgi_ssi.c 是cgi和ssi的处理

将httpd_cgi_ssi.c中关于硬件操作的代码删掉，或者找到宏LWIP_HTTPD_SSI和宏LWIP_HTTPD_CGI将SSI和CGI功能禁掉，然后在主程序中增加httpd_init()。

上电运行后可以看到ST官方例子的网页：

三、打印网页接收数据

在httpd.c中的http_recv函数中增加以下黄色部分代码：

然后当在浏览器打开192.168.2.8时，串口输出以下数据：

get msg from 192:168:2:194 port:55329:
GET / HTTP/1.1
Host: 192.168.2.8
Connection: keep-alive
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8
Accept-Encoding: gzip, deflate
Accept-Language: zh-CN,zh;q=0.9


get msg from 192:168:2:194 port:55330:
GET /STM32F4x7_files/ST.gif HTTP/1.1
Host: 192.168.2.8
Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36
Accept: image/webp,image/apng,image/*,*/*;q=0.8
Referer: http://192.168.2.8/
Accept-Encoding: gzip, deflate
Accept-Language: zh-CN,zh;q=0.9


get msg from 192:168:2:194 port:55331:
GET /STM32F4x7_files/stm32.jpg HTTP/1.1
Host: 192.168.2.8
Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36
Accept: image/webp,image/apng,image/*,*/*;q=0.8
Referer: http://192.168.2.8/
Accept-Encoding: gzip, deflate
Accept-Language: zh-CN,zh;q=0.9


get msg from 192:168:2:194 port:55332:
GET /inchtml-pages-stm32_connectivity_files/pixel.gif HTTP/1.1
Host: 192.168.2.8
Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36
Accept: image/webp,image/apng,image/*,*/*;q=0.8
Referer: http://192.168.2.8/
Accept-Encoding: gzip, deflate
Accept-Language: zh-CN,zh;q=0.9


get msg from 192:168:2:194 port:55334:
GET /favicon.ico HTTP/1.1
Host: 192.168.2.8
Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36
Accept: image/webp,image/apng,image/*,*/*;q=0.8
Referer: http://192.168.2.8/
Accept-Encoding: gzip, deflate
Accept-Language: zh-CN,zh;q=0.9

由此可以看出，打开了网页服务器地址，会给网页服务器发送GET / HTTP/1.1命令，网页服务器会根据这个命令找到index.html，然后给浏览器返回网页数据。由于网页数据中又包含了一些照片资源，因此浏览器再给网页服务器发送

GET /STM32F4x7_files/ST.gif HTTP/1.1
GET /STM32F4x7_files/stm32.jpg HTTP/1.1
GET /inchtml-pages-stm32_connectivity_files/pixel.gif HTTP/1.1
GET /favicon.ico HTTP/1.1

以获取照片资源。