csocket.cpp

来自「一个简单的http下载程序,用C++在linux下写了一个简单的http下载程序」· C++ 代码 · 共 179 行

#include "CSocket.h"

Sock_instance::Sock_instance(string hostname, unsigned port, s_type type)
	: _hostname( hostname ), 
	 _port( port ),
	 _fd( 0 ),
	 _state( CONN_ERROR ),
	 _type( type )
{
	_datalen = 0;
	_data = new unsigned char[1024*1024];
}

Sock_instance::~Sock_instance()
{
	delete[] _data;
}

bool Sock_instance::Connect()
{
	if( _type == SERVER_TYPE )
	{
		cout << "The socket is a server, don't use conncet!" << endl;
		return false;
	}
	
	struct sockaddr_in peer;
	int fd;

	bzero( &peer, sizeof(peer) );
	peer.sin_family = AF_INET;
	struct hostent *hp = gethostbyname( _hostname.c_str() );	
	if ( hp == NULL )
	{
		cout << "unknow host: " << _hostname << endl;
		return false;
	}
	peer.sin_addr = *( ( struct in_addr * )hp->h_addr );
	peer.sin_port	= htons(_port);

	cout << "conncet to " << inet_ntoa(peer.sin_addr)  << ": " << ntohs( peer.sin_port ) << endl;
	
	fd = socket( AF_INET, SOCK_STREAM, 0 );
	if ( fd < 0 )
	{
		cout <<  "socket call failed" << endl;
		return false;
	}

	if( connect( fd, (struct sockaddr *)&peer, sizeof( peer ) ) )
	{
		cout << errno << "connect failed" << endl;
		_state = CONN_ERROR;
		close( fd );
		return false;
	}

	_state = CONN_OK;
	_fd = fd;
	
	return true;
}

s_state Sock_instance::state()
{
	return _state;
}

int Sock_instance::fd()
{
	return _fd;
}

bool Sock_instance::Send(string msg)
{
	if( state() != CONN_OK )
	{
		cout << "the socket is not ok" << endl;
		return false;
	}

	int rc;

	if((rc = send(_fd, msg.c_str(), msg.size(), 0)) == -1)
	{
		if((errno != EWOULDBLOCK) && (errno != EAGAIN))
		{
			_state = CONN_ERROR;
			return false;
		}
	}
	return true;
}

int Sock_instance::Receive()
{
	int rc;
	char buf[BUFSIZ];
	char *p_buf = buf;

	static bool b_readhead = true;

	bzero(buf, BUFSIZ);

	if((rc = recv( _fd, buf, BUFSIZ - 1, 0 )) < 0 )
	{
		cout << "recive error" << endl;
		_state = CONN_WAIT;
		Close();
	}
	else if( rc == 0 )
	{
		cout << "server teminated" << endl;
		_state = CONN_WAIT;
		Close();
	}
	else
	{
		//read HTTP head
		int ix = 0;
		while( b_readhead )
		{
			// 2 0D 0A just for head end
			if( ix >= rc )
				break;
			if( buf[ix] == 13 && buf[ix+1] == 10 && buf[ix+2] == 13 && buf[ix+3] == 10 )
			{
				b_readhead = false;
				char *p = new char[ix+5];
				memset( p, 0, ix+5 );
				memcpy( p, buf, ix+5 );
				p_buf += ix + 5;
				_http_head = p;
				delete[] p;
				cout << _http_head << endl;
				break;
			}
			ix ++;
		}

		//copy data to _data
		if( ix != 0 && ix < rc )
		{
			//this buf has head so data begin with buf+ix+4
			memcpy( _data+_datalen, buf+ix+4, rc-ix-4 );
			_datalen += rc-ix-4;
		}
		else
		{
			memcpy( _data+_datalen, buf, rc );
			_datalen += rc;	
		}
	}

	return rc;
}

inline void Sock_instance::Close()
{
	close( _fd );
}

//string Sock_instance::data() const
unsigned char * Sock_instance::data() const
{
	return _data;
}

int Sock_instance::datalen() const
{
	return _datalen;
}

string Sock_instance::http_head() const
{
	return _http_head;
}