目录
- 0.CGI程序主要干什么?
- 1.数据处理
- 2.任务处理
0.CGI程序主要干什么?
- CGI数据处理主要由外部CGI程序负责,HttpServer只负责将拿到的参数交给CGI程序
- 即:CGI程序既需要数据处理又需要任务处理,最后将结果传递回HttpServer
- 本质上就是给一个某个功能的软件,套上了一层壳
- 解析HttpServer传递的参数
- 实现某个功能
- 将结果传递回HttpServer
1.数据处理
bool GetQuery(std::string& out)
{std::string method = getenv("METHOD");bool ret = false;if (method == "GET"){out = getenv("ARG");ret = true;}else if (method == "POST"){int content_length = atoi(getenv("CLENGTH"));char ch = 'K';while (content_length--){read(0, &ch, 1);out.push_back(ch);}ret = true;}else{}return ret;
}void CutString(const std::string& in, std::string& out1, std::string& out2, const std::string sep)
{auto pos = in.find(sep);if(pos != std::string::npos){out1 = in.substr(0, pos);out2 = in.substr(pos + sep.size());}
}
2.任务处理
- 将解析出来的参数,用于任务处理,处理什么任务,就需要看具体场景,写具体代码了
- 此处以一个简易计算器为例
int main()
{std::string queryStr;GetQuery(queryStr);std::string arg1, arg2;CutString(queryStr, arg1, arg2, "&");std::string key1, value1, key2, value2;CutString(arg1, key1, value1, "=");CutString(arg2, key2, value2, "=");std::cout << key1 << ":" << value1 << endl;std::cout << key2 << ":" << value2 << endl;std::cerr << "CGI: " << key1 << ":" << value1 << endl;std::cerr << "CGI: " << key2 << ":" << value2 << endl;int x = atoi(value1.c_str());int y = atoi(value2.c_str());std::cout << "<html>";std::cout << "<head><meta charset=\"utf-8\"></head>";std::cout << "<body>";std::cout << "<h3> " << value1 << " + " << value2 << " = " << x + y << "</h3>";std::cout << "<h3> " << value1 << " - " << value2 << " = " << x - y << "</h3>";std::cout << "<h3> " << value1 << " * " << value2 << " = " << x * y << "</h3>";std::cout << "<h3> " << value1 << " / " << value2 << " = " << x / y << "</h3>";std::cout << "</body>";std::cout << "</html>";return 0;
}