近年来,我国嵌入式系统应用产品日益丰富,市场呈现快速增长趋势,尤其在通信、家电、电子、汽车、通信、交通、金融、网络、监控、工业自动化等领域应用更加广泛,发展嵌入式系统技术和产业已经成为惯彻“信息化带动工业化,工业化促进信息化”的方针,使我国产品由“中国制造”向“中国创造”迈进的突破口。随着计算进网络技术的发展和个人PC的普及, 局域网的发展也同样迅速。很多政府机构,企业,学校,都是先以一个统一的局域网联结在一起,再分别接入INTERNET.因此基于局域网的即时通信工具,就这样应运而生了为人们提供了一种新的联系方式,为在同一小范围内(如同一办公楼)的用户在即使通信上提供了方便。所以,本文将实现基于linux的聊天功能设计与实现开发,为局域网用户提供方便的网络通信。
本系统实现了聊天室的基本功能。该程序是在Ubuntu环境下编写和调试客户端与服务器端程序,实现了客户端和服务端连接并通信并实现了群聊、私聊和字体样式设置的功能。服务器端程序是通过vi编辑器,使用C、C++编写并利用了MySql数据库的相关知识。客户端程序是用Qt实现图形化界面和与服务器的通信。
接下来本文将会详细讲解此聊天系统的关键代码的实现与功能,包括如何建立连接,如何进行登陆和注册,如何进行私聊和群聊,等等。
关键词:嵌入式;聊天系统;数据库;QT
In recent years, embedded system application products increasingly rich in our co- untry, the market showed a trend of rapid growth, especially in the communica- tions, home appliances, electronics, automotive, communications, transportation, finance, networking, monitoring, industrial automation and other fields used more widely, the development of embedded system technology and industry has become used to toru "informationization to drive industrialization and industrialization pro- motes infor- matization" policy, to make our products from "made in China" to "created in China" into the breach. As computing into the development of network technology and the popularity of PC, the development of local area network (LAN) is also quickly. Many government agencies, enterprises, schools, local area network (LAN) is the first in a unified link together, then respectively access to the INTERNET, so instant communication tools based on local area network (LAN), thus arises at the historic moment the contact provides a new way for people, for the small in the same area of an office building user in even if provides a convenient communication. Therefore, the implementation of embedded chat system development, provide network comm- unication convenient for users in lan.
This system realized the basic function of the chat room. The program is written in the Ubuntu environment and debug client and server program, realized the client and the server connection and communication. Server application is through the vi editor, use C, C + + programming language and use the related knowledge of MySql datab- ase. The client program is implemented using Qt graphical interface and the commu- nication with the server.
Next, this article will explain in detail the implementation of the key code of the chat system and function, including how to establish a connection, if you register and login, how to do private and group chat, and so on.
Key words:embedded; chat system; database; QT
目 录
摘 要i
Abstractii
1 绪论1
1.1 研究背景及意义1
1.2 研究现状1
1.3 研究内容2
1.4 论文组织结构2
2 开发平台和相关技术简介3
2.1 嵌入式系统定义3
2.2 嵌入式Linux的主要特征3
2.3 QT的发展及编程机制3
2.4 TCP/IP协议简介5
2.5 Socket套接字简介6
2.6 C++语言简介8
3 可行性研究和需求分析10
3.1 可行性研究10
3.1.1 经济可行性分析10
3.1.2 技术可行性分析10
3.1.2 法律可行性分析10
3.2 需求分析10
3.2.1 用户需求11
3.2.2 功能需求11
3.2.3 性能需求12
4 系统的总体设计13
4.1 体系结构设计13
4.2 功能模块设计13
4.2.1 客户端功能模块的设计14
4.2.2 服务器端功能模块的划分15
4.2.3 数据库设计15
5 系统的详细设计及编码实现16
5.1 客户端实现16
5.1.1 连接服务器模块17
5.1.2 登陆模块18
5.1.3 注册模块20
5.1.4 私聊模块22
5.1.5 群聊模块24
5.1.6 设置字体模块25
5.2 服务器端实现29
5.2.1 服务器中数据库模块29
5.2.2 服务器模块实现32
6 系统使用简介和功能测试35
6.1 聊天系统使用介绍35
6.2 服务端编译35
6.3 客户端的编译35
6.4 系统启动测试35
6.4.1 服务端启动测试36
6.4.2 客户端启动测试36
6.4.3 性能测试38
结论39
参考文献40
致 谢41
外文原文42
中文翻译53