在第一篇中，已经说明，传递的socket地址采取以下形式：
[cpp] view plaincopyprint?
stream://192.168.2.10:8080
dgram://192.168.2.10:8080
stream://unix.domain.ipc
dgram://unix.domain.ipc
stream://192.168.2.10:8080
dgram://192.168.2.10:8080
stream://unix.domain.ipc
dgram://unix.domain.ipc今天看一下这个uri地址的解析过程，是如何转化成socket地址的，废话不多说，直接上代码
/***************************************************************************************
****************************************************************************************
* FILE : socket_addr.h
* Description :
*
* Copyright (c) 2012 by Liu Yanyun(E-mail:liuyun827@foxmail.com). All Rights Reserved.
* Without permission, shall not be used for any commercial purpose
*
* History:
* Version Name Date Description
0.1 Liu Yanyun 2012/12/05 Initial Version
****************************************************************************************
****************************************************************************************/
#ifndef _SOCKET_ADDR_H_
#define _SOCKET_ADDR_H_
#include <stdio.h>
#include <string.h>
#include <stdint.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <stddef.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <arpa/inet.h>
#include <string>
#include <iostream>
/*==================================================================
* class : SockAddr
* Description : parse uri address and serialize to string
==================================================================*/
class SockAddr
{
public:
/*==================================================================
* Function : SockAddr.SockAddr
* Description : construction function
* Input Para : uri address sting
* Output Para : null
* Return Value:
==================================================================*/
SockAddr(std::string uri_);
/*==================================================================
* Function : SockAddr.SockAddr
* Description : construction function
* Input Para : domain_ -- address family
* Input Para : type_ -- specifies the communication semantics
* Output Para : null
* Return Value:
==================================================================*/
SockAddr(int domain_, int type_);
/*==================================================================
* Function : SockAddr.~SockAddr
* Description : Destructor function
* Input Para :
* Output Para :
* Return Value:
==================================================================*/
virtual ~SockAddr();
/*==================================================================
* Function : SockAddr.parseUri
* Description : parse uri to socket address
* Input Para : void
* Output Para :
* Return Value: if success return true,or else false return
==================================================================*/
bool parseUri();
/*==================================================================
* Function : SockAddr.toStr
* Description : convert socket address to uri
* Input Para : store uri buf
* Output Para : uri string
* Return Value: if success return true,or else false return
==================================================================*/
bool toStr(std::string &str_);
/*==================================================================
* Function : SockAddr.getDomain
* Description : get socket domain
* Input Para : void
* Output Para :
* Return Value: address famliy
==================================================================*/
int getDomain();
/*==================================================================
* Function : SockAddr.getType
* Description : get communication type
* Input Para : void
* Output Para :
* Return Value: communication type
==================================================================*/
int getType();
/*==================================================================
* Function : SockAddr.getSockLen
* Description : get socket addrss length
* Input Para : void
* Output Para :
* Return Value: socket addrss length
==================================================================*/
socklen_t getSockLen();
/*==================================================================
* Function : SockAddr.getAddr
* Description : get socket addrss
* Input Para : void
* Output Para :
* Return Value: socket addrss pointer
==================================================================*/
struct sockaddr* getAddr();
private:
static const int unixMaxPath = 108 - 1;
//AF_INET; AF_UNIX
int domain;
//SOCK_STREAM; SOCK_DGRAM
int type;
union
{
struct sockaddr_in inetAddr;
struct sockaddr_un unixAddr;
};
std::string uri;
};
#endif /*_SOCKET_ADDR_H_*/
目前不支持ipv6协议，从上面的union可以看出；
L127：静态常量unixMaxPath是unix域套接字中使用的，表示路径的最大长度-1；
/***************************************************************************************
****************************************************************************************
* FILE : socket_addr.cc
* Description :
*
* Copyright (c) 2012 by Liu Yanyun(E-mail:liuyun827@foxmail.com). All Rights Reserved.
* Without permission, shall not be used for any commercial purpose
*
* History:
* Version Name Date Description
0.1 Liu Yanyun 2012/12/05 Initial Version
****************************************************************************************
****************************************************************************************/
#include "log_trace.h"
#include "socket_addr.h"
using namespace std;
SockAddr::SockAddr(std::string uri_)
{
uri = uri_;
domain = 0;
type = 0;
memset(&unixAddr, 0, sizeof(unixAddr));
}
SockAddr::SockAddr(int domain_, int type_)
{
domain = domain_;
type = type_;
memset(&unixAddr, 0, sizeof(unixAddr));
}
SockAddr::~SockAddr()
{
//do nothing
}
struct sockaddr* SockAddr::getAddr()
{
if(AF_INET == domain)
{
return (struct sockaddr*)&inetAddr;
}
else if(AF_UNIX == domain)
{
return (struct sockaddr*)&unixAddr;
}
else
{
logTrace("invalid sockct domain:%d", domain);
return NULL;
}
}
int SockAddr::getDomain()
{
return domain;
}
int SockAddr::getType()
{
return type;
}
socklen_t SockAddr::getSockLen()
{
if(AF_INET == domain)
{
return sizeof(inetAddr);
}
else if(AF_UNIX == domain)
{
return sizeof(unixAddr);
}
else
{
logTrace("invalid sockct domain:%d", domain);
return 0;
}
}
/*
"stream://127.0.0.1:8888"
"dgram://127.0.0.1:8888"
"stream://string"
"dgram://string"
*/
bool SockAddr::parseUri()
{
string::size_type pos = uri.find ("://");
if(string::npos == pos)
{
logTrace("invalid uri:%s", uri.c_str());
return false;
}
string protocol = uri.substr (0, pos);
string addrStr = uri.substr (pos + 3);
if(protocol.empty () || addrStr.empty ())
{
logTrace("invalid uri:%s", uri.c_str());
return false;
}
if("stream" == protocol)
{
type = SOCK_STREAM;
}
else if("dgram" == protocol)
{
type = SOCK_DGRAM;
}
else
{
logTrace("invalid uri:%s", uri.c_str());
return false;
}
pos = addrStr.find (":");
if(string::npos == pos)
{
domain = AF_UNIX;
unixAddr.sun_family = AF_UNIX;
snprintf(&unixAddr.sun_path[1], unixMaxPath, "%s", addrStr.c_str());
return true;
}
else
{
domain = AF_INET;
inetAddr.sin_family = AF_INET;
string ip = addrStr.substr (0, pos);
string port = addrStr.substr (pos + 1);
if(ip.empty () || port.empty ())
{
logTrace("invalid uri:%s", uri.c_str());
return false;
}
inetAddr.sin_port = htons(atoi(port.c_str()));
if("*" == ip)
{
inetAddr.sin_addr.s_addr = htonl (INADDR_ANY);
}
else
{
int rc = inet_pton(AF_INET, ip.c_str(), &inetAddr.sin_addr);
if(rc <= 0)
{
logTrace("invalid uri:%s;%m", uri.c_str());
return false;
}
}
return true;
}
}
bool SockAddr::toStr(string &str_)
{
if("" != uri)
{
str_ = uri;
return true;
}
if(AF_INET == domain)
{
char ipStr[INET_ADDRSTRLEN] = {0};
if(NULL == inet_ntop(AF_INET, &inetAddr.sin_addr, ipStr, INET_ADDRSTRLEN))
{
logTrace("invalid sin_addr;%m");
return false;
}
char tmp[256] = {0};
if(SOCK_STREAM == type)
{
snprintf(tmp, sizeof(tmp), "stream://%s:%d", ipStr, ntohs(inetAddr.sin_port));
}
else if(SOCK_DGRAM == type)
{
snprintf(tmp, sizeof(tmp), "dgram://%s:%d", ipStr, ntohs(inetAddr.sin_port));
}
else
{
logTrace("invalid type:%d", type);
return false;
}
str_ = tmp;
uri = tmp;
return true;
}
else if(AF_UNIX == domain)
{
char tmp[256] = {0};
if(SOCK_STREAM == type)
{
snprintf(tmp, sizeof(tmp), "stream://%s", &unixAddr.sun_path[1]);
}
else if(SOCK_DGRAM == type)
{
snprintf(tmp, sizeof(tmp), "dgram://%s", &unixAddr.sun_path[1]);
}
else
{
logTrace("invalid type:%d", type);
return false;
}
str_ = tmp;
uri = tmp;
return true;
}
else
{
logTrace("invalid sockct domain:%d", domain);
return false;
}
}
L41：返回的socket地址是根据domain判定的
L92：首先查找'://'前面的字串表示使用的是字节流协议还是数据包协议
L121：在从剩余子串中查找':'，找到标识采用的是ip:port形式，即使用的是inet域协议，找不到认为是unix域协议
L142：对server端ip为'*'，表示绑定到任意网卡
L160：返回socket地址对应的uri字符串，主要用在采用数据包协议时需要获取对端地址的情况
上面的这个类对于使用者是不可见的，属于内部使用类。