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calvinwilliams / tcpdaemon

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README
LGPL-2.1

tcpdaemon

0.快速开始

老师交给小明一个开发任务,实现一个TCP网络迭代并发服务器,用于回射任何接收到的通讯数据。小明很懒,他在开源中国项目库里搜到了开源库tcpdaemon来帮助他快速完成任务。首先他安装好tcpdaemon,然后写了一个C程序文件test_callback_echo.c

$ vi test_callback_echo.c
#include "tcpdaemon.h"

_WINDLL_FUNC int tcpmain( struct TcpdaemonServerEnvironment *p_env , int sock , void *p_addr )
{
	char	buffer[ 4096 ] ;
	int	len ;
	
	len = recv( sock , buffer , sizeof(buffer) , 0 ) ;
	if( len == 0 )
		return TCPMAIN_RETURN_CLOSE;
	else if( len < 0 )
		return TCPMAIN_RETURN_ERROR;
    
	len = send( sock , buffer , len , 0 ) ;
	if( len < 0 )
		return TCPMAIN_RETURN_ERROR;
	
	return TCPMAIN_RETURN_WAITINGFOR_NEXT;
}

他编译链接成动态库test_callback_echo.so,最后用tcpdaemon直接挂接执行

$ tcpdaemon -m IF -l 0:9527 -s test_callback_echo.so -c 10 --tcp-nodelay --logfile $HOME/log/test_callback_echo.log

OK,总共花了五分钟,圆满完成老师作业。老师说这个太简单了,小明你给我改成像Apache经典的Leader-Follow服务端模型,小明说没问题,他把启动命令参数-m IF改成了-m LF,再次执行,完成老师要求,总共花了五秒钟。老师问你怎么这么快就改好了,小明说全靠开源项目tcpdaemon帮了大忙啊 ^_^

1.概述

tcpdaemon是一个TCP通讯服务端平台/库,它封装了众多常见服务端进程/线程管理和TCP连接管理模型(Forking、Leader-Follow、IO-Multiplex、WindowsThreads Leader-Follow),使用者只需加入TCP通讯数据收发和应用逻辑代码就能快速构建出完整的TCP应用服务器。

服务模型 模型说明
Forking 单进程主守护,每当一条TCP新连接进来后,接受之,创建子进程进入回调函数tcpmain处理之。一条连接对应一个子进程(短生命周期)
Leader-Follow 单进程管理进程,预先创建一组子进程(长生命周期)并监控其异常重启。子进程等待循环争抢TCP新连接调用回调函数tcpmain处理之
IO-Multiplex 单进程主守护,IO多路复用等待TCP新连接进来事件、TCP数据到来事件,TCP数据可写事件,调用回调函数tcpmain处理之
WindowsThreads Leader-Follow 同Leader-Follow,区别在于预先创建一组子线程而非子进程

tcpdaemon提供了三种与使用者代码对接方式:(注意:.exe只是为了说明自己是可执行文件,在UNIX/Linux中可执行文件一般没有扩展名)

链接模式 链接关系 说明
回调模式 tcpdaemon.exe+user.so(tcpmain) 可执行程序tcpdaemon通过启动命令行参数挂接用户动态库,获得动态库中函数tcpmain指针。当建立TCP连接后 或 IO多路复用模式下当可读可写事件发生时 调用回调函数tcpmain
主调模式 user.exe(main,tcpmain)+libtcpdaemon.a(tcpdaemon) 用户可执行程序user.exe隐式链接库libtcpdaemon.a。用户函数main(user.exe)初始化tcpdaemon参数结构体,并设置回调函数tcpmain,调用函数tcpdaemon(libtcpdaemon.so)。当建立TCP连接后 或 IO多路复用模式下当可读可写事件发生时 调用回调函数tcpmain
主调+回调模式 user.exe(main)+libtcpdaemon.a(tcpdaemon) + user.so(tcpmain) 同上,区别在于用户函数main不直接设置回调函数tcpmain而设置user.so文件名。函数tcpdaemon负责挂接动态库user.so并获得函数tcpmain指针

一般简单情况下,使用者采用回调模式即可,只要编写一个动态库user.so(内含回调函数tcpmain)被可执行程序tcpdaemon挂接上去运行。如果使用者想订制一些自定义处理,如初始化环境,可以采用主调模式,实现函数main里把自定义参数传递给tcpdaemon穿透给tcpmain。如果想实现运行时选择回调函数tcpmain则可以采用主调+回调模式。

2.编译安装

以Linux操作系统为例,下载到最新源码安装包tcpdaemon-x.y.z.tar.gz到某目录,解压之

$ tar xvzf tcpdaemon-x.y.z.tar.gz
...
$ cd tcpdaemon
$ cd src
$ make -f makefile.Linux install
rm -f LOGC.o
rm -f tcpdaemon_lib.o
rm -f tcpdaemon_main.o
rm -f tcpdaemon
rm -f libtcpdaemon.a
gcc -g -fPIC -O2 -Wall -Werror -fno-strict-aliasing -I. -I/home/calvin/include  -c tcpdaemon_lib.c
gcc -g -fPIC -O2 -Wall -Werror -fno-strict-aliasing -I. -I/home/calvin/include  -c LOGC.c
ar rv libtcpdaemon.a tcpdaemon_lib.o LOGC.o
ar: 正在创建 libtcpdaemon.a
a - tcpdaemon_lib.o
a - LOGC.o
gcc -g -fPIC -O2 -Wall -Werror -fno-strict-aliasing -I. -I/home/calvin/include  -c tcpdaemon_main.c
gcc -g -fPIC -O2 -Wall -Werror -fno-strict-aliasing  -o tcpdaemon tcpdaemon_main.o tcpdaemon_lib.o LOGC.o -L. -L/home/calvin/lib -lpthread -ldl 
cp -rf tcpdaemon /home/calvin/bin/
cp -rf libtcpdaemon.a /home/calvin/lib/
cp -rf tcpdaemon.h /home/calvin/include/tcpdaemon/

可以看到可执行程序tcpdaemon安装到$HOME/bin,静态库libtcpdaemon.a安装到$HOME/lib,开发用的头文件安装到$HOME/include/tcpdaemon。

3.使用示例

3.1.服务模型Forking,链接模式1,接收HTTP请求报文然后发送HTTP响应报文

使用者只需编写一个函数tcpmain,实现同步的接收HTTP请求报文然后发送HTTP响应报文回去

$ vi test_callback_http_echo.c
#include "tcpdaemon.h"

_WINDLL_FUNC int tcpmain( struct TcpdaemonServerEnvironment *p_env , int sock , void *p_addr )
{
	char	http_buffer[ 4096 + 1 ] ;
	long	http_len ;
	long	len ;
	
	/* 接收HTTP请求 */
	memset( http_buffer , 0x00 , sizeof(http_buffer) );
	http_len = 0 ;
	while( sizeof(http_buffer)-1 - http_len > 0 )
	{
		len = RECV( sock , http_buffer + http_len , sizeof(http_buffer)-1 - http_len , 0 ) ;
		if( len == 0 )
			return TCPMAIN_RETURN_CLOSE;
		if( len == -1 )
			return TCPMAIN_RETURN_ERROR;
		if( strstr( http_buffer , "\r\n\r\n" ) )
			break;
		http_len += len ;
	}
	if( sizeof(http_buffer)-1 - http_len <= 0 )
	{
		return TCPMAIN_RETURN_ERROR;
	}
	
	/* 发送HTTP响应 */
	memset( http_buffer , 0x00 , sizeof(http_buffer) );
	http_len = 0 ;
	http_len = sprintf( http_buffer , "HTTP/1.0 200 OK\r\nContent-length: 17\r\n\r\nHello Tcpdaemon\r\n" ) ;
	SEND( sock , http_buffer , http_len , 0 );
	
	return TCPMAIN_RETURN_CLOSE;
}

编译链接成test_callback_http_echo.so

$ gcc -g -fPIC -O2 -Wall -Werror -fno-strict-aliasing -I. -I/home/calvin/include/tcpdaemon  -c test_callback_http_echo.c
$ gcc -g -fPIC -O2 -Wall -Werror -fno-strict-aliasing -shared -o test_callback_http_echo.so test_callback_http_echo.o -L. -L/home/calvin/lib -lpthread -ldl 

用tcpdaemon直接挂接即可

$ tcpdaemon -m IF -l 0:9527 -s test_callback_http_echo.so -c 10 --tcp-nodelay --logfile $HOME/log/test_callback_http_echo.log --loglevel-debug

可执行程序tcpdaemon所有命令行参数可以不带参数的执行而得到

$ tcpdaemon
USAGE : tcpdaemon -m IF -l ip:port -s so_pathfilename [ -c max_process_count ]
                  -m LF -l ip:port -s so_pathfilename -c process_count [ -n max_requests_per_process ]
        other options :
                  -v
                  [ --daemon-level ]
                  [ --work-path work_path ]
                  [ --work-user work_user ]

执行后可在$HOME/log下可以看到tcpdaemon的日志。

通过curl发测试请求

$ curl "http://localhost:9527/"
Hello Tcpdaemon

测试成功!

所有代码在源码安装包的test目录里下可以找到

3.2.服务模型IO-Multiplex,链接模式2,非堵塞的接收HTTP请求报文然后发送HTTP响应报文

使用者编写一个函数main

$ test_main_IOMP.c
#include "tcpdaemon.h"

extern int tcpmain( struct TcpdaemonServerEnvironment *p_env , int sock , void *p_addr );

int main()
{
	struct TcpdaemonEntryParameter	ep ;
	
	memset( & ep , 0x00 , sizeof(struct TcpdaemonEntryParameter) );
	
	snprintf( ep.log_pathfilename , sizeof(ep.log_pathfilename) , "%s/log/test_main_IOMP.log" , getenv("HOME") );
	ep.log_level = LOGLEVEL_DEBUG ;
	
	strcpy( ep.server_model , "IOMP" );
    ep.timeout_seconds = 60 ;
	strcpy( ep.ip , "0" );
	ep.port = 9527 ;
    ep.tcp_nodelay = 1 ;
	
	ep.process_count = 1 ;
	
	ep.pfunc_tcpmain = & tcpmain ;
	ep.param_tcpmain = NULL ;
	
	return -tcpdaemon( & ep );
}

结构体TcpdaemonEntryParameter所有成员说明在tcpdaemon.h里可以找到

struct TcpdaemonEntryParameter
{
	int		daemon_level ;	/* 是否转化为守护服务 1:转化 0:不转化(缺省) */
	
	char		log_pathfilename[ 256 + 1 ] ;	/* 日志输出文件名,不设置则输出到标准输出上 */
	int		log_level ;	/* 日志等级 */
	
	char		server_model[ 10 + 1 ] ;	/* TCP连接管理模型
							LF:领导者-追随者预派生进程池模型 for UNIX,Linux
							IF:即时派生进程模型 for UNIX,Linux
							WIN-TLF:领导者-追随者预派生线程池模型 for win32
						IOMP:进程池+多路复用模型 for UNIX,Linux 回调函数内应分支事件处理
							*/
	int		process_count ;	/* 当为领导者-追随者预派生进程池模型时为工作进程池进程数量,当为即时派生进程模型时为最大子进程数量,当为IO多路复用模型时为工作进程池进程数量 */
	int		max_requests_per_process ;	/* 当为领导者-追随者预派生进程池模型时为单个工作进程最大处理应用次数 */
	char		ip[ 20 + 1 ] ;	/* 本地侦听IP */
	int		port ;	/* 本地侦听PORT */
	char		so_pathfilename[ 256 + 1 ] ;	/* 用绝对路径或相对路径表达的应用动态库文件名 */
	
	char		work_user[ 64 + 1 ] ;	/* 切换为其它用户运行。可选 */
	char		work_path[ 256 + 1 ] ;	/* 切换到指定目录运行。可选 */
	
	func_tcpmain	*pfunc_tcpmain ;	/* 当函数调用模式时,指向把TCP连接交给应用入口函数指针 */
	void		*param_tcpmain ;	/* 当函数调用模式时,指向把TCP连接交给应用入口函数的参数指针。特别注意:自己保证线程安全 */
	
	int		tcp_nodelay ;	/* 启用TCP_NODELAY选项 1:启用 0:不启用(缺省)。可选 */
	int		tcp_linger ;	/* 启用TCP_LINGER选项 >=1:启用并设置成参数值 0:不启用(缺省)。可选 */
	
    int     timeout_seconds ; /* 超时时间,单位:秒;目前只对IO-Multiplex模型有效 */
    
	/* 以下为内部使用 */
	int		install_winservice ;
	int		uninstall_winservice ;
} ;

使用者再编写一个函数tcpmain,实现非堵塞的接收HTTP请求报文然后发送HTTP响应报文回去

$ vi test_callback_http_echo_nonblock.c
#include "tcpdaemon.h"

struct AcceptedSession
{
	int		sock ; /* socket描述字 */
	struct sockaddr	addr ; /* socket地址 */
	
	char	http_buffer[ 4096 + 1 ] ; /* HTTP收发缓冲区 */
	int		read_len ; /* 读了多少字节 */
	int		write_len ; /* 将要写多少字节 */
	int		wrote_len ; /* 写了多少字节 */
} ;

_WINDLL_FUNC int tcpmain( struct TcpdaemonServerEnvironment *p_env , int sock , void *p_addr )
{
	struct AcceptedSession	*p_accepted_session = NULL ;
	int			len ;
	
	switch( TDGetIoMultiplexEvent(p_env) )
	{
		/* 接受新连接事件 */
		case IOMP_ON_ACCEPTING_SOCKET :
			/* 申请内存以存放已连接会话 */
			p_accepted_session = (struct AcceptedSession *)malloc( sizeof(struct AcceptedSession) ) ;
			if( p_accepted_session == NULL )
				return TCPMAIN_RETURN_ERROR;
			memset( p_accepted_session , 0x00 , sizeof(struct AcceptedSession) );
			
			p_accepted_session->sock = sock ;
			memcpy( & (p_accepted_session->addr) , p_addr , sizeof(struct sockaddr) );
			
			/* 设置已连接会话数据结构 */
			TDSetIoMultiplexDataPtr( p_env , p_accepted_session );
			
			/* 等待读事件 */
			return TCPMAIN_RETURN_WAITINGFOR_RECEIVING;
			
		/* 关闭连接事件 */
		case IOMP_ON_CLOSING_SOCKET :
			/* 释放已连接会话 */
			p_accepted_session = (struct AcceptedSession *) p_addr ;
			free( p_accepted_session );
			
			/* 等待下一任意事件 */
			return TCPMAIN_RETURN_WAITINGFOR_NEXT;
			
		/* 通讯接收事件 */
		case IOMP_ON_RECEIVING_SOCKET :
			p_accepted_session = (struct AcceptedSession *) p_addr ;
			
			/* 非堵塞接收通讯数据 */
			len = RECV( p_accepted_session->sock , p_accepted_session->http_buffer+p_accepted_session->read_len , sizeof(p_accepted_session->http_buffer)-1-p_accepted_session->read_len , 0 ) ;
			if( len == 0 )
				return TCPMAIN_RETURN_CLOSE;
			else if( len == -1 )
				return TCPMAIN_RETURN_ERROR;
			
			/* 已接收数据长度累加 */
			p_accepted_session->read_len += len ;
			
			/* 如果已收完 */
			if( strstr( p_accepted_session->http_buffer , "\r\n\r\n" ) )
			{
				/* 组织响应报文 */
				p_accepted_session->write_len = sprintf( p_accepted_session->http_buffer , "HTTP/1.0 200 OK\r\n"
											"Content-length: 17\r\n"
											"\r\n"
											"Hello Tcpdaemon\r\n" ) ;
				return TCPMAIN_RETURN_WAITINGFOR_SENDING;
			}
			
			/* 如果缓冲区收满了还没收完 */
			if( p_accepted_session->read_len == sizeof(p_accepted_session->http_buffer)-1 )
				return TCPMAIN_RETURN_ERROR;
			
			/* 等待下一任意事件 */
			return TCPMAIN_RETURN_WAITINGFOR_NEXT;
			
		/* 通讯发送事件 */
		case IOMP_ON_SENDING_SOCKET :
			p_accepted_session = (struct AcceptedSession *) p_addr ;
			
			/* 非堵塞发送通讯数据 */
			len = SEND( p_accepted_session->sock , p_accepted_session->http_buffer+p_accepted_session->wrote_len , p_accepted_session->write_len-p_accepted_session->wrote_len , 0 ) ;
			if( len == -1 )
				return TCPMAIN_RETURN_ERROR;
			
			/* 已发送数据长度累加 */
			p_accepted_session->wrote_len += len ;
			
			/* 如果已发完 */
			if( p_accepted_session->wrote_len == p_accepted_session->write_len )
				return TCPMAIN_RETURN_CLOSE;
			
			/* 等待下一任意事件 */
			return TCPMAIN_RETURN_WAITINGFOR_NEXT;
			
		default :
			return TCPMAIN_RETURN_ERROR;
	}
}

编译成test_main_IOMP

gcc -g -fPIC -O2 -Wall -Werror -fno-strict-aliasing -I. -I/home/calvin/include/tcpdaemon  -c test_main_IOMP.c
gcc -g -fPIC -O2 -Wall -Werror -fno-strict-aliasing -I. -I/home/calvin/include/tcpdaemon  -c test_callback_http_echo_nonblock.c
gcc -g -fPIC -O2 -Wall -Werror -fno-strict-aliasing  -o test_main_IOMP test_main_IOMP.o test_callback_http_echo_nonblock.o -L. -L/home/calvin/lib -lpthread -ldl  -ltcpdaemon

执行test_main_IOMP

$ ./test_main_IOMP

执行后可在$HOME/log下可以看到test_main_IOMP的日志。

通过curl发测试请求

$ curl "http://localhost:9527/"
Hello Tcpdaemon

测试成功!

所有代码在源码安装包的test目录里下可以找到

4.参考

4.1.回调函数tcpmain

tcpdaemon会在合适时机回调用户层指定函数tcpmain。

当服务模型为Forking或Leader-Follow或WindowsThreads Leader-Follow时,回调函数tcpmain在连接被接受后调用。返回TCPMAIN_RETURN_CLOSE或TCPMAIN_RETURN_ERROR都将关闭通讯连接。

当服务模型为IO-Multiplex时,回调函数tcpmain在通讯连接被接受时、通讯连接被关闭时、通讯数据可接收/发送时调用,因为是非堵塞处理,返回TCPMAIN_RETURN_CLOSE或TCPMAIN_RETURN_ERROR会关闭通讯连接,返回TCPMAIN_RETURN_WAITINGFOR_RECEIVING会切换等待可读事件,返回TCPMAIN_RETURN_WAITINGFOR_SENDING会切换等待可写事件,返回TCPMAIN_RETURN_WAITINGFOR_NEXT会继续等待其它事件。(注意:通讯连接被接受时的tcpmain里必须调用TDSetIoMultiplexDataPtr设置通讯数据会话结构)

4.2.TcpdaemonServerEnvironment环境函数集

函数名 TDGetTcpmainParameter
函数原型 void *TDGetTcpmainParameter( struct TcpdaemonServerEnvironment *p_env );
输入参数 struct TcpdaemonServerEnvironment *p_env tcpdaemon环境结构指针
返回值 调用tcpmain时传入TcpdaemonEntryParameter的param_tcpmain地址
函数名 TDGetListenSocket
函数原型 int TDGetListenSocket( struct TcpdaemonServerEnvironment *p_env );
输入参数 struct TcpdaemonServerEnvironment *p_env tcpdaemon环境结构指针
返回值 侦听端口描述字
函数名 TDGetListenSocketPtr
函数原型 int *TDGetListenSocketPtr( struct TcpdaemonServerEnvironment *p_env );
输入参数 struct TcpdaemonServerEnvironment *p_env tcpdaemon环境结构指针
返回值 侦听端口描述字的地址
函数名 TDGetListenAddress
函数原型 struct sockaddr_in TDGetListenAddress( struct TcpdaemonServerEnvironment *p_env );
输入参数 struct TcpdaemonServerEnvironment *p_env tcpdaemon环境结构指针
返回值 侦听端口网络地址
函数名 TDGetListenAddressPtr
函数原型 struct sockaddr_in *TDGetListenAddressPtr( struct TcpdaemonServerEnvironment *p_env );
输入参数 struct TcpdaemonServerEnvironment *p_env tcpdaemon环境结构指针
返回值 侦听端口网络地址的地址
函数名 TDGetProcessCount
函数原型 int TDGetProcessCount( struct TcpdaemonServerEnvironment *p_env );
输入参数 struct TcpdaemonServerEnvironment *p_env tcpdaemon环境结构指针
返回值 配置最大并发度或静态进程池进程数量
函数名 TDGetEpollArrayBase
函数原型 int *TDGetEpollArrayBase( struct TcpdaemonServerEnvironment *p_env );
输入参数 struct TcpdaemonServerEnvironment *p_env tcpdaemon环境结构指针
返回值 IO多路复用epoll数组第一个元素的地址
函数名 TDGetThisEpoll
函数原型 int TDGetThisEpoll( struct TcpdaemonServerEnvironment *p_env );
输入参数 struct TcpdaemonServerEnvironment *p_env tcpdaemon环境结构指针
返回值 当前IO多路复用epoll描述字
函数名 TDGetIoMultiplexEvent
函数原型 int TDGetIoMultiplexEvent( struct TcpdaemonServerEnvironment *p_env );
输入参数 struct TcpdaemonServerEnvironment *p_env tcpdaemon环境结构指针
返回值 当前IO多路复用epoll事件 IOMP_ON_ACCEPTING_SOCKET:接受新连接事件 IOMP_ON_CLOSING_SOCKET:关闭连接事件 IOMP_ON_RECEIVING_SOCKET:接收通讯数据事件 IOMP_ON_SENDING_SOCKET:发送通讯数据事件

5.总结

tcpdaemon提供了多种服务模型和链接模式,旨在协助使用者快速构建TCP应用服务器,比如可以使用本人的另一个开源项目 HTTP解析器fasterhttp 以百行以内代码构建出一个完整的Web服务器,还有一个完整的应用案例可参阅本人的另一个开源项目 分布式发号器 ,经过tcpdaemon改造后应用代码缩短了一半。

tcpdaemon源码托管在 开源中国码云,你也可以通过 邮箱 联系到作者

能帮助到您是我的荣幸 ^_^

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简介

tcpdaemon是一个TCP通讯服务端平台/库,它封装了众多常见服务端进程/线程管理和TCP连接管理模型(Forking、Leader-Follow、IO-Multiplex、WindowsThreads Leader-Follow),使用者只需加入TCP通讯数据收发和应用逻辑代码就能快速构建出完整的TCP应用服务器。 展开 收起
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