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前奏

今天，我找回了阔别已久的迷路的感觉，我觉得，顺序什么的，算了算了，还是按照我的喜好来。

网络模块的文件：

依旧要房山管理放上人家的版权：

• Copyright © 2006-2012, Salvatore Sanfilippo
• All rights reserved.

初潮

ane.c和anet.h中的内容主要用于简单的TCP Socket连接。

先来看一下头文件，一半是熟悉的面孔，一半听我说完也是熟悉的面孔了嘿嘿

#ifndef ANET_H#define ANET_H#include 
   
    #define ANET_OK 0#define ANET_ERR -1#define ANET_ERR_LEN 256/* Flags used with certain functions. */#define ANET_NONE 0#define ANET_IP_ONLY (1<<0)#if defined(__sun) || defined(_AIX)#define AF_LOCAL AF_UNIX#endif#ifdef _AIX#undef ip_len#endifint anetTcpConnect(char *err, const char *addr, int port);	//TCP的默认连接int anetTcpNonBlockConnect(char *err, const char *addr, int port);	//TCP的非阻塞连接int anetTcpNonBlockBindConnect(char *err, const char *addr, int port, const char *source_addr);	//TCP的非阻塞绑定int anetTcpNonBlockBestEffortBindConnect(char *err, const char *addr, int port, const char *source_addr);//字面意思啊：TCP的最高效非阻塞绑定，等下我倒要看看到底是何方神圣，虽然我心里有个答案了//下面俩是unix的int anetUnixConnect(char *err, const char *path);int anetUnixNonBlockConnect(char *err, const char *path);int anetRead(int fd, char *buf, int count);int anetResolve(char *err, char *host, char *ipbuf, size_t ipbuf_len);	//解析所有东西int anetResolveIP(char *err, char *host, char *ipbuf, size_t ipbuf_len);//单单解析IPint anetTcpServer(char *err, int port, char *bindaddr, int backlog);int anetTcp6Server(char *err, int port, char *bindaddr, int backlog);int anetUnixServer(char *err, char *path, mode_t perm, int backlog);int anetTcpAccept(char *err, int serversock, char *ip, size_t ip_len, int *port);int anetUnixAccept(char *err, int serversock);int anetWrite(int fd, char *buf, int count);int anetNonBlock(char *err, int fd);		//anet设置非阻塞的方法 int anetBlock(char *err, int fd);int anetEnableTcpNoDelay(char *err, int fd);	//启用非延迟int anetDisableTcpNoDelay(char *err, int fd);int anetTcpKeepAlive(char *err, int fd);	//心跳保活机制int anetSendTimeout(char *err, int fd, long long ms);int anetRecvTimeout(char *err, int fd, long long ms);int anetPeerToString(int fd, char *ip, size_t ip_len, int *port);	//转换网络字节序int anetKeepAlive(char *err, int fd, int interval);int anetSockName(int fd, char *ip, size_t ip_len, int *port);//格式化，等下看看是何方神圣int anetFormatAddr(char *fmt, size_t fmt_len, char *ip, int port);	int anetFormatPeer(int fd, char *fmt, size_t fmt_len);int anetFormatSock(int fd, char *fmt, size_t fmt_len);
   

高潮迭起

工具包

anet.c

anetTcpConnect

int anetTcpConnect(char *err, const char *addr, int port){
       return anetTcpGenericConnect(err,addr,port,NULL,ANET_CONNECT_NONE);}

/*	参数释义：		addr：传入服务器地址信息，其中内容将用于创建监听套接字		source_addr：相当于客户端地址信息		flags：这我还真没看明白。。。再最后一块儿，注释给出了，如果没猜错，应该是和仅打开监听套接字有关的*/static int anetTcpGenericConnect(char *err, const char *addr, int port,const char *source_addr, int flags){
       int s = ANET_ERR, rv;    char portstr[6];  /* strlen("65535") + 1; */    struct addrinfo hints, *servinfo, *bservinfo, *p, *b;    snprintf(portstr,sizeof(portstr),"%d",port);    memset(&hints,0,sizeof(hints));    hints.ai_family = AF_UNSPEC;	//未指定    hints.ai_socktype = SOCK_STREAM;//有序、可靠、面向连接的双向字节流    if ((rv = getaddrinfo(addr,portstr,&hints,&servinfo)) != 0) {
   	//解析addr信息，存入 servinfo    //不懂一定要看上面的工具包，写了一晚上呢        anetSetError(err, "%s", gai_strerror(rv));	//这个不管它，报错函数而已        return ANET_ERR;    }    for (p = servinfo; p != NULL; p = p->ai_next) {
   		//工具包里有说，给你一个addrinfo，它可能是一串        /* Try to create the socket and to connect it.         * If we fail in the socket() call, or on connect(), we retry with         * the next entry in servinfo. */        if ((s = socket(p->ai_family,p->ai_socktype,p->ai_protocol)) == -1)	//这里s成为了监听套接字            continue;	//如果没打开，那就继续循环，无碍        if (anetSetReuseAddr(err,s) == ANET_ERR) goto error;	//设置地址重用        if (flags & ANET_CONNECT_NONBLOCK && anetNonBlock(err,s) != ANET_OK)	//设置非阻塞            goto error;        if (source_addr) {
   	//source_addr：传入参数            int bound = 0;            /* Using getaddrinfo saves us from self-determining IPv4 vs IPv6 */            if ((rv = getaddrinfo(source_addr, NULL, &hints, &bservinfo)) != 0)	//内啥，不多说了啊            {
                   anetSetError(err, "%s", gai_strerror(rv));                goto error;            }            for (b = bservinfo; b != NULL; b = b->ai_next) {
                   if (bind(s,b->ai_addr,b->ai_addrlen) != -1) {
                       bound = 1;                    break;                }            }            freeaddrinfo(bservinfo);            if (!bound) {
                   anetSetError(err, "bind: %s", strerror(errno));                goto error;            }        }	//for循环到这里结束        if (connect(s,p->ai_addr,p->ai_addrlen) == -1) {
               /* If the socket is non-blocking, it is ok for connect() to             * return an EINPROGRESS error here. */            if (errno == EINPROGRESS && flags & ANET_CONNECT_NONBLOCK)                goto end;            close(s);            s = ANET_ERR;            continue;        }        /* If we ended an iteration of the for loop without errors, we         * have a connected socket. Let's return to the caller. */        goto end;    }    if (p == NULL)        anetSetError(err, "creating socket: %s", strerror(errno));error:    if (s != ANET_ERR) {
           close(s);        s = ANET_ERR;    }end:    freeaddrinfo(servinfo);    /* Handle best effort binding: if a binding address was used, but it is     * not possible to create a socket, try again without a binding address. */    if (s == ANET_ERR && source_addr && (flags & ANET_CONNECT_BE_BINDING)) {
   	    //#define ANET_CONNECT_BE_BINDING 2 /* Best effort binding. */        return anetTcpGenericConnect(err,addr,port,NULL,flags);    } else {
           return s;    }}

int anetTcpNonBlockBindConnect(char *err, const char *addr, int port,const char *source_addr){
       return anetTcpGenericConnect(err,addr,port,source_addr,ANET_CONNECT_NONBLOCK);}int anetTcpNonBlockBestEffortBindConnect(char *err, const char *addr, int port,const char *source_addr){
       return anetTcpGenericConnect(err,addr,port,source_addr,ANET_CONNECT_NONBLOCK|ANET_CONNECT_BE_BINDING);}

潮落

anetUnixConnect

int anetUnixConnect(char *err, const char *path){
       return anetUnixGenericConnect(err,path,ANET_CONNECT_NONE);}

int anetUnixGenericConnect(char *err, const char *path, int flags){
       int s;    struct sockaddr_un sa;    if ((s = anetCreateSocket(err,AF_LOCAL)) == ANET_ERR)	//在下边，简单调用而已，本地连接        return ANET_ERR;    sa.sun_family = AF_LOCAL;	//既然是本地连接，那就不多说了    strncpy(sa.sun_path,path,sizeof(sa.sun_path)-1);    if (flags & ANET_CONNECT_NONBLOCK) {
           if (anetNonBlock(err,s) != ANET_OK) {
               close(s);            return ANET_ERR;        }    }    if (connect(s,(struct sockaddr*)&sa,sizeof(sa)) == -1) {
           if (errno == EINPROGRESS &&            flags & ANET_CONNECT_NONBLOCK)            return s;        anetSetError(err, "connect: %s", strerror(errno));        close(s);        return ANET_ERR;    }    return s;}static int anetCreateSocket(char *err, int domain) {
       int s;    if ((s = socket(domain, SOCK_STREAM, 0)) == -1) {
           anetSetError(err, "creating socket: %s", strerror(errno));        return ANET_ERR;    }    /* Make sure connection-intensive things like the redis benchmark     * will be able to close/open sockets a zillion of times */    if (anetSetReuseAddr(err,s) == ANET_ERR) {
           close(s);        return ANET_ERR;    }    return s;}

int anetUnixNonBlockConnect(char *err, const char *path){
       return anetUnixGenericConnect(err,path,ANET_CONNECT_NONBLOCK);}

Read、Write

int anetRead(int fd, char *buf, int count){
       ssize_t nread, totlen = 0;    while(totlen != count) {
           nread = read(fd,buf,count-totlen);        if (nread == 0) return totlen;        if (nread == -1) return -1;        totlen += nread;        buf += nread;    }    return totlen;}

int anetWrite(int fd, char *buf, int count){
       ssize_t nwritten, totlen = 0;    while(totlen != count) {
           nwritten = write(fd,buf,count-totlen);        if (nwritten == 0) return totlen;        if (nwritten == -1) return -1;        totlen += nwritten;        buf += nwritten;    }    return totlen;}

这俩已经太熟了，也不知道要说啥

时间、心跳，相关

/* Set the socket send timeout (SO_SNDTIMEO socket option) to the specified * number of milliseconds, or disable it if the 'ms' argument is zero. */int anetSendTimeout(char *err, int fd, long long ms) {
       struct timeval tv;    tv.tv_sec = ms/1000;    tv.tv_usec = (ms%1000)*1000;    if (setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv)) == -1) {
           anetSetError(err, "setsockopt SO_SNDTIMEO: %s", strerror(errno));        return ANET_ERR;    }    return ANET_OK;}/* Set the socket receive timeout (SO_RCVTIMEO socket option) to the specified * number of milliseconds, or disable it if the 'ms' argument is zero. */int anetRecvTimeout(char *err, int fd, long long ms) {
       struct timeval tv;    tv.tv_sec = ms/1000;    tv.tv_usec = (ms%1000)*1000;    if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv)) == -1) {
           anetSetError(err, "setsockopt SO_RCVTIMEO: %s", strerror(errno));        return ANET_ERR;    }    return ANET_OK;}//如果对setsockopt不了解，没事儿，我在上边补了个工具包。

int anetTcpKeepAlive(char *err, int fd){
       int yes = 1;    if (setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, &yes, sizeof(yes)) == -1) {
           anetSetError(err, "setsockopt SO_KEEPALIVE: %s", strerror(errno));        return ANET_ERR;    }    return ANET_OK;}

高潮再起

anetResolve

int anetResolve(char *err, char *host, char *ipbuf, size_t ipbuf_len) {
       return anetGenericResolve(err,host,ipbuf,ipbuf_len,ANET_NONE);}

int anetGenericResolve(char *err, char *host, char *ipbuf, size_t ipbuf_len,int flags){
       struct addrinfo hints, *info;    int rv;    memset(&hints,0,sizeof(hints));    if (flags & ANET_IP_ONLY) hints.ai_flags = AI_NUMERICHOST;    hints.ai_family = AF_UNSPEC;    hints.ai_socktype = SOCK_STREAM;  /* specify socktype to avoid dups */    if ((rv = getaddrinfo(host, NULL, &hints, &info)) != 0) {
           anetSetError(err, "%s", gai_strerror(rv));        return ANET_ERR;    }    if (info->ai_family == AF_INET) {
           struct sockaddr_in *sa = (struct sockaddr_in *)info->ai_addr;        inet_ntop(AF_INET, &(sa->sin_addr), ipbuf, ipbuf_len);    } else {
           struct sockaddr_in6 *sa = (struct sockaddr_in6 *)info->ai_addr;        inet_ntop(AF_INET6, &(sa->sin6_addr), ipbuf, ipbuf_len);    }    freeaddrinfo(info);    return ANET_OK;}

好滴吧，没有前面那个那么猛烈

int anetResolveIP(char *err, char *host, char *ipbuf, size_t ipbuf_len) {
       return anetGenericResolve(err,host,ipbuf,ipbuf_len,ANET_IP_ONLY);}

字节序转换

int anetPeerToString(int fd, char *ip, size_t ip_len, int *port) {
       struct sockaddr_storage sa;    socklen_t salen = sizeof(sa);    if (getpeername(fd,(struct sockaddr*)&sa,&salen) == -1) goto error;    if (ip_len == 0) goto error;    if (sa.ss_family == AF_INET) {
           struct sockaddr_in *s = (struct sockaddr_in *)&sa;        if (ip) inet_ntop(AF_INET,(void*)&(s->sin_addr),ip,ip_len);        if (port) *port = ntohs(s->sin_port);    } else if (sa.ss_family == AF_INET6) {
           struct sockaddr_in6 *s = (struct sockaddr_in6 *)&sa;        if (ip) inet_ntop(AF_INET6,(void*)&(s->sin6_addr),ip,ip_len);        if (port) *port = ntohs(s->sin6_port);    } else if (sa.ss_family == AF_UNIX) {
           if (ip) strncpy(ip,"/unixsocket",ip_len);        if (port) *port = 0;    } else {
           goto error;    }    return 0;error:    if (ip) {
           if (ip_len >= 2) {
               ip[0] = '?';            ip[1] = '\0';        } else if (ip_len == 1) {
               ip[0] = '\0';        }    }    if (port) *port = 0;    return -1;}

好累啊，那要不就到这儿吧，其他的基本是调用调用再调用，工具包里有。

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