LuaSocket 简介：
LuaSocket is a Lua extension library that is composed by two parts:a C core that provides support for the TCP and UDP transport layers, and a set of Lua modules that add support for functionality commonly needed by applications that deal with the Internet.the core support has been implemented so that it is both efficient and simple to use. It is available to any Lua application once it has been properly initialized by the interpreter in use.The code has been tested and runs well on several Windows and Unix platforms.LuaSocket version 2.0.2 is now available for download! It is compatible with Lua 5.1, and has been tested on Windows XP, Linux, and Mac OS X.2.0.2 is just a bug-fix/update release.LuaSocket 是一个Lua的拓展库。包括两个部分：Ｃ语言编写提供Tcp和Udp 传输层协议的核心模块和支持处理网络Lua模块。核心模块被高效且简单的是实现。仅仅要嵌入lua解释器就可以使用。核心模块已经在多个windows和unix 操作系统测试和运行。LuaSocket 2.0.2版本和Lua 5.1.x版本兼容,已经在window xp ,linux 和 Mac os X操作系统测试过。LuaSocket 作为一个bug 修复版本释放。
LuaSocket 使用：
本文使用windows 7 操作系统和使用vs2010 工具。所以仅仅测试winsock api 部分。
1,在导入头文件和源文件时,移除usocket等相关unix操行系统下的文件。
2 在wsocket.h 中加入 #pragma comment(lib,"ws2_32.lib") 导入 winsock库,否则在link过程中,会找到socket api相关函数。
luasocketsample.cpp 文件内容如下：
extern "C" {#include "lua.h"#include "lauxlib.h"#include "lualib.h"#include "luasocket.h" //使用LuaSocket 库仅仅需要包含的头文件。}int main(int argc, char **argv){//创建lua_State lua_State *L = lua_open(); /* create state */ //注册标准库 luaL_openlibs (L); //注册LuaSocket库 luaopen_socket_core(L); //执行sample_1.lua luaL_dofile (L, "luasocketsample.lua"); //关闭lua_State lua_close(L);return 1;}在LuaSocket 源代码中有例子,以下例子取自echosrvr.lua 文件并部分修改：local host = host or "127.0.0.1"local port = port or 8080print("Binding to host '" ..host.. "' and port " ..port.. "…")–创建udp对象udp = assert(socket.udp())–绑定到指定的端口assert(udp:setsockname(host, port))–设置超时时间assert(udp:settimeout(5))–获取绑定IP和端口ip, port = udp:getsockname()assert(ip, port)print("Waiting packets on " .. ip .. ":" .. port .. "…")local recvmaxbyte =20–单线程无限循环while 1 do–接收udp packetdgram, ip, port = udp:receivefrom(recvmaxbyte)if(dgram=="终止")thenprint("终止")breakendif dgram thenprint("Echoing '" .. dgram .. "' to " .. ip .. ":" .. port)–发送数据udp:sendto(dgram, ip, port)elseprint(ip)endendudp=nilcollectgarbage("collect")运行结果如下：
luasocket文件为使用LuaSokct 需要包含的文件,代码非常简单。
/*=========================================================================*\* LuaSocket toolkit* Networking support for the Lua language* Diego Nehab* 26/11/1999** This library is part of an effort to progressively increase the network* connectivity of the Lua language. The Lua interface to networking* functions follows the Sockets API closely, trying to simplify all tasks* involved in setting up both client and server connections. The provided* IO routines, however, follow the Lua style, being very similar to the* standard Lua read and write functions.** RCS ID: $Id: luasocket.c,v 1.53 2005/10/07 04:40:59 diego Exp $\*=========================================================================*//*=========================================================================*\* Standard include files\*=========================================================================*/#include "lua.h"#include "lauxlib.h"#if !defined(LUA_VERSION_NUM) || (LUA_VERSION_NUM < 501)#include "compat-5.1.h"#endif/*=========================================================================*\* LuaSocket includes\*=========================================================================*/#include "luasocket.h"#include "auxiliar.h"#include "except.h"#include "timeout.h"#include "buffer.h"#include "inet.h"#include "tcp.h"#include "udp.h"#include "select.h"/*————————————————————————-*\* Internal function prototypes\*————————————————————————-*/static int global_skip(lua_State *L);static int global_unload(lua_State *L);static int base_open(lua_State *L);/*————————————————————————-*\* Modules and functions\*————————————————————————-*///这是LuaSocket 提供的所有Lua 模块功能static const luaL_reg mod[] ={{"auxiliar", auxiliar_open},{"except", except_open},{"timeout", timeout_open},{"buffer", buffer_open},{"inet", inet_open},{"tcp", tcp_open},{"udp", udp_open},{"select", select_open},{NULL, NULL}};static luaL_reg func[] ={{"skip",global_skip},{"__unload", global_unload},{NULL,NULL}};/*————————————————————————-*\* Skip a few arguments\*————————————————————————-*/static int global_skip(lua_State *L){int amount = luaL_checkint(L, 1);int ret = lua_gettop(L) – amount – 1;return ret >= 0 ? ret : 0;}/*————————————————————————-*\* Unloads the library\*————————————————————————-*/static int global_unload(lua_State *L){(void) L;socket_close();return 0;}/*————————————————————————-*\* Setup basic stuff.\*————————————————————————-*/static int base_open(lua_State *L){//通过判断不同操作系统提供的socket 基础,在window操作系统是使用winsock2.0版本if (socket_open()) {/* export functions (and leave namespace table on top of stack) *///注册LuaSocket到_G["socket"]luaL_openlib(L, "socket", func, 0);#ifdef LUASOCKET_DEBUGlua_pushstring(L, "_DEBUG");lua_pushboolean(L, 1);lua_rawset(L, -3);#endif/* make version string available to scripts */lua_pushstring(L, "_VERSION");lua_pushstring(L, LUASOCKET_VERSION);lua_rawset(L, -3);return 1;} else {lua_pushstring(L, "unable to initialize library");lua_error(L);return 0;}}/*————————————————————————-*\* Initializes all library modules.\*————————————————————————-*///使用LuaSocket ,luaopen_socket_core()函数来注册所有相关模块.LUASOCKET_API int luaopen_socket_core(lua_State *L) {int i;base_open(L);for (i = 0; mod[i].name; i++) mod[i].func(L);return 1;}小结：
LuaSocket 作为Lua的网络拓展库,使用LuaSocket 可以跨平台。可以在window ,unix 以及mac 操作系统下面使用。window 平台下面,LuaSocket 仅仅使用14个头文件。
源代码行数在大于1000行到2000行之间。库小，很容易理解学习。在window 操作系统下面，，仅仅使用了select IO模型。像Java Nio 底层也是封装了window操行系统的select
才能做到人在旅途，感悟人生，享受人生。
