wy_sockaddr.h

一个不错

/* Copyright is licensed under GNU LGPL.                 by I.J.Wang 2003

   Base protocol class of socket address.
*/

#ifndef WY_SOCKADDR_H__
#define WY_SOCKADDR_H__
#define WY_SOCKADDR_VERSION 31

#include "wyret.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <string.h>      // for memcpy

class WyStr;

/*
  note: Wy::wrd(const Wy_SockAddr&) is reserved(use notation member)
        Because wrd for each socket address is defined and a question in mind
        that wrd(const Wy_SockAddr&) might need to output the address type
        .caller has enough info. to convert back
*/
class Wy_SockAddr {
    friend class WySockFile;
  public:
    virtual ~Wy_SockAddr() {};

    int family(void) const WY__TSPC()
         { return this->c_sockaddr().sa_family; };

    virtual WyRet notation(WyStr& str) const=0;

    // [Syn]
    //    std::memcpy(&this->c_sockaddr(),&src.c_sockaddr(),src.c_addrlen());
    //    *this->c_addrlen=*src.c_addrlen();
    // 
    // Note: Application ensure that this->c_sockaddr_size()>=src.c_addrlen,
    //       or address structure is overwritten.
    //
    // Note: This member may be called in constructor
    //       This member is to avoid exposure c_sockadddr().. in public
    //       interface
    /*
    void _copy_sockaddr(const Wy_SockAddr& src) WY__TSPC()
      {
        std::memcpy(&this->c_sockaddr(),&src.c_sockaddr(),src.c_addrlen());
        this->c_addrlen()=src.c_addrlen();
       };*/
  protected:

    // [Internal] Reset the address
    //   
    // Note: sockaddr.sa_family is setup by the derived class and should
    //       be constant throughout object life time.
    //
    // [Throw] No Reply is thrown
    //
    virtual void reset(void) WY__TSPC()=0;

    // [Syn] Interchange object state of *this with saddr
    //
    // [Ret] Ok
    //       Wym_EBADTYPE
    //
    virtual WyRet _swap(Wy_SockAddr& saddr) WY__TSPC()=0;

    // [Internal] Allocate an default object (use delete to destroy)
    //            and reset ptr to point to it.
    //
    // [Throw] No Reply is thrown
    //
    // [Ret] Ok
    //       Wym_ENOMEM
    //       Wym_ENOSYS   Not overridden
    //       ...          (From constructing the default object)
    //
    virtual Wy_SockAddr* _alloc(WyRet& r) const=0;

    // [Internal] Get address of the underlying sockaddr structure
    //
    // Note: Derived class should always setup sockaddr.sa_family data member.
    //       Codes in WySockFile depends on this to identify the data structure.
    //
    //  struct ::sockaddr& c_sockaddr(void)
    //  size_t c_sockaddr_size(void) const
    //  socklen_t& c_addrlen(void)
    //
    // Note: These membesr may be called in constructor of this object
    //       Function behavior can not depend on *this object state
    //
    // [Ret] address of struct sockaddr
    //
    virtual struct ::sockaddr& c_sockaddr(void) WY__TSPC()=0;
    virtual const struct ::sockaddr& c_sockaddr(void) const WY__TSPC()=0;

    // [Internal] Get the size that c_sockaddr() pointed to
    //            (the maximumal char size pointed by c_sockaddr)
    //            This value is normally written to *c_addrlen when
    //            calling accept/getsockname/getpeername
    //         .sizeof the structure pointed by c_sockaddr
    // [Ret] The buffer size c_sockaddr() pointed to
    //
    virtual size_t c_sockaddr_size(void) const WY__TSPC()=0;

    // [Internal] Get/Set the effective length of the address structure
    //            pointed by c_sockaddr (<=c_sockaddr_size)
    // 
    // [Ret] Address of the variable that specifies the valid data
    //       length c_sockaddr() pointed.
    //
    virtual  socklen_t& c_addrlen(void) WY__TSPC()=0;
    virtual const socklen_t& c_addrlen(void) const WY__TSPC()=0;
};

#endif