conn.cpp

linux下的一款播放器

/* ***** BEGIN LICENSE BLOCK *****
 * Source last modified: $Id: conn.cpp,v 1.9.30.3 2004/07/09 01:47:02 hubbe Exp $
 * 
 * Portions Copyright (c) 1995-2004 RealNetworks, Inc. All Rights Reserved.
 * 
 * The contents of this file, and the files included with this file,
 * are subject to the current version of the RealNetworks Public
 * Source License (the "RPSL") available at
 * http://www.helixcommunity.org/content/rpsl unless you have licensed
 * the file under the current version of the RealNetworks Community
 * Source License (the "RCSL") available at
 * http://www.helixcommunity.org/content/rcsl, in which case the RCSL
 * will apply. You may also obtain the license terms directly from
 * RealNetworks.  You may not use this file except in compliance with
 * the RPSL or, if you have a valid RCSL with RealNetworks applicable
 * to this file, the RCSL.  Please see the applicable RPSL or RCSL for
 * the rights, obligations and limitations governing use of the
 * contents of the file.
 * 
 * Alternatively, the contents of this file may be used under the
 * terms of the GNU General Public License Version 2 or later (the
 * "GPL") in which case the provisions of the GPL are applicable
 * instead of those above. If you wish to allow use of your version of
 * this file only under the terms of the GPL, and not to allow others
 * to use your version of this file under the terms of either the RPSL
 * or RCSL, indicate your decision by deleting the provisions above
 * and replace them with the notice and other provisions required by
 * the GPL. If you do not delete the provisions above, a recipient may
 * use your version of this file under the terms of any one of the
 * RPSL, the RCSL or the GPL.
 * 
 * This file is part of the Helix DNA Technology. RealNetworks is the
 * developer of the Original Code and owns the copyrights in the
 * portions it created.
 * 
 * This file, and the files included with this file, is distributed
 * and made available on an 'AS IS' basis, WITHOUT WARRANTY OF ANY
 * KIND, EITHER EXPRESS OR IMPLIED, AND REALNETWORKS HEREBY DISCLAIMS
 * ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET
 * ENJOYMENT OR NON-INFRINGEMENT.
 * 
 * Technology Compatibility Kit Test Suite(s) Location:
 *    http://www.helixcommunity.org/content/tck
 * 
 * Contributor(s):
 * 
 * ***** END LICENSE BLOCK ***** */

#include "hlxclib/time.h"
#include <string.h>
#if defined(_UNIX)
#include <sys/types.h>
#endif
#include "hlxclib/sys/socket.h"
#include "hlxclib/netdb.h"

#include "hxcom.h"
#include "conn.h"

#include "hxengin.h"
#include "hxcom.h"
#include "hxtick.h"
#include "hxresult.h"
#include "hxthread.h"
#include "hxbuffer.h"
#include "hxstrutl.h"
#include "netbyte.h"

#if defined( THREADS_SUPPORTED ) || defined(_UNIX_THREADED_NETWORK_IO)
#include "thrdconn.h"
#endif

//#include "../dcondev/dcon.h"

#include "hxheap.h"
#ifdef _DEBUG
#undef HX_THIS_FILE		
static const char HX_THIS_FILE[] = __FILE__;
#endif									 

#define MAX_CONN_STARVINGTIME	1000

// DNR cache
DNR_cache	conn::mCache[MAX_CACHE];
UINT16		conn::mCacheCount = 0;

// conn object list
// XXXJR Really sorry this, but as an actual instance it doesn't get
// initialized when linked into a shared library under unix.  Yuck.
CHXMapPtrToPtr*	conn::mConnectionList	    = NULL;
HXThread*	conn::m_pNetworkThread	    = NULL;
UINT32  	conn::m_ulMaxBandwidth	    = MAX_UINT32;   // in bytes per sec
UINT32		conn::m_ulTCPTotalBytesRead = 0;
UINT32		conn::m_ulTCPReadTimeStamp  = 0;
CHXSimpleList*	conn::m_pTCPStarvingList    = NULL;
BOOL            conn::m_bNetworkThreading   = FALSE;
BOOL            conn::m_bThreadedDNS        = FALSE;

static HXMutex* z_pConnectionListMutex = NULL;

DestructConnGlobals selfConnGlobalDestructor;

void		
conn::DestructGlobals()
{
    HX_DELETE(z_pConnectionListMutex);
}

// new_socket() creates the correct version of conn depending on the
// defined platform and requested socket type
conn* conn::new_socket (UINT16 type)
{
    conn *c = 0;

#if defined(_UNIX_THREADED_NETWORK_IO)
    if( conn::GetNetworkThreadingPref() )
    {
        c = ThreadedConn::new_socket(type);
    }
    else
    {
        c = actual_new_socket(type);
    }
#elif defined(THREADS_SUPPORTED)
    c = ThreadedConn::new_socket(type);
#else    
    c = actual_new_socket(type);
#endif

    if ( c != NULL )
    {
	conn::add_connection_to_list ( c );
	c->AddRef();
    }

    return(c);
}

conn::~conn (void)
{
//    dprintf("**Destructor** conn::conn(%X)\n", this);
    if (m_pUDPBuffer)
    {
	delete [] m_pUDPBuffer;
	m_pUDPBuffer = 0;
    }

    if ( this != NULL )
	    conn::remove_connection_from_list ( this );
}


// platform specific constructor should set the socket to a value  
// indicating the connection is not open
conn::conn (void)
    : m_bNoAsyncDNS( FALSE )
{
//	if ( this != NULL )
//		dprintf("==Constructor== conn::conn(%X)\n", this);
	mSock = HX_INVALID_SOCKET;
	mConnectionOpen = 0;
	mLastError = HXR_OK;
	mCallBack = 0;
	mHostIPAddr = 0;
	mHostIPValid = FALSE;
	mDNSDone	 = FALSE;
	m_pUDPBuffer	 = 0;
	m_ulLastStarvingTime = 0; 
}

/* 	conn::is_cached searches the cached DNR for host and returns its inet address 
	in  addr and 1 if it was found, or 0 if it was not found */

UINT16
conn::is_cached(char *host,ULONG32 *addr)
{
	UINT16 found = 0;
	
	for (UINT16 i=0; i < mCacheCount && !found; i++) 
	{
		if (mCache[i].domainName && (::strcmp(host, mCache[i].domainName) == 0)) 
		{
			*addr = mCache[i].addr;
			found = 1;
		}
	}
	return found;
}

/* 	conn::add_to_cache adds the host and its inet addr to the cache. If the cache is
	full, the oldest entry is replaced with the new entry */

void		
conn::add_to_cache(char *host,ULONG32 addr)
{
	UINT16 found = 0;
	
	// search the cache to see if entry has already been entered
	for (UINT16 i=0; i < mCacheCount && !found; i++) 
	{
		DNR_cache_ptr p = &mCache[i];

		if(addr == p->addr && p->domainName && (::strcmp(host, p->domainName) == 0)) 
		{
			::time(&p->cachetime);	// refresh cache time
			found = 1;
		}
	}

	if(found) return;  			// our work here is done
	
	if(mCacheCount < MAX_CACHE) // add the new entry to the end of the cache array
	{
		DNR_cache_ptr p = &mCache[mCacheCount];
		p->addr = addr;
		::time(&p->cachetime);
		if (p->domainName != host)
		{
		    HX_VECTOR_DELETE(p->domainName);
		    p->domainName = ::new_string(host);
		}
		mCacheCount++;
	}
	else // search cache for oldest entry and replace it with the new data
	{
		time_t minTime = mCache[0].cachetime;
		UINT16 minPos = 0;
		for(UINT16 i = 1; i < mCacheCount; i++)
		{
			if(mCache[i].cachetime < minTime)
			{
				minTime = mCache[i].cachetime;
				minPos = i;
			}
		}
		
		DNR_cache_ptr p = &mCache[minPos];
		p->addr = addr;
		::time(&p->cachetime);		// time of caching
		if (p->domainName != host)
		{
		    HX_VECTOR_DELETE(p->domainName);
		    p->domainName = ::new_string(host);
		}
	}
}

void		
conn::remove_from_cache(const char *host)
{
	UINT16 found = 0;
	// search the cache to see if entry has been entered
	for (UINT16 i = 0; i < mCacheCount && !found; i++) 
	{
		DNR_cache_ptr p = &mCache[i];
		if(p->domainName && ::strcmp(host, p->domainName) == 0) 
		{
			HX_VECTOR_DELETE(p->domainName);
			p->addr = 0;
			p->cachetime = 0;	// reset time to 0
			found = 1;
		}
	}
}

void			
conn::clear_cache()
{
    mCacheCount = 0;
}


POSITION
conn::get_first_connection_position ()
{
    if(!conn::mConnectionList)
    {
	return NULL;
    }

    return conn::mConnectionList->GetStartPosition();
}

void
conn::get_next_connection(POSITION& nextPos, conn*& rpConn)
{
    if(!conn::mConnectionList)
    {
	nextPos	= NULL;
	rpConn	= NULL;
	return;
    }

    void* pVoid = NULL;
    conn::mConnectionList->GetNextAssoc ( nextPos, (void *&)rpConn, pVoid );
}

void
conn::add_connection_to_list ( conn *pConn )
{
    if (!z_pConnectionListMutex)
    {
#if defined(_UNIX_THREADED_NETWORK_IO)
        if( conn::GetNetworkThreadingPref() )
        {
            HXMutex::MakeMutex(z_pConnectionListMutex);
        }
        else
        {
            HXMutex::MakeStubMutex(z_pConnectionListMutex);
        }
#elif defined(THREADS_SUPPORTED)
        HXMutex::MakeMutex(z_pConnectionListMutex);
#else    
        HXMutex::MakeStubMutex(z_pConnectionListMutex);
#endif
    }
    
    HX_ASSERT( z_pConnectionListMutex);
    z_pConnectionListMutex->Lock();

    //fprintf(stderr, "==AddToList== conn::add_connection_to_list(%X)\n", pConn);
    if(!conn::mConnectionList)
    {
	conn::mConnectionList = new CHXMapPtrToPtr;
    }
        
    conn::mConnectionList->SetAt ( pConn, NULL );
    z_pConnectionListMutex->Unlock();
}

void
conn::remove_connection_from_list ( conn *pConn )
{
    LISTPOSITION    listpos = NULL;
    CHXSimpleList::Iterator  i;

    if(!conn::mConnectionList)
    {
	return;
    }
    
    HX_ASSERT(z_pConnectionListMutex);
    if (z_pConnectionListMutex)
    {
	z_pConnectionListMutex->Lock();
    }

    HX_VERIFY (conn::mConnectionList->RemoveKey ( pConn ) );
    if (conn::m_pTCPStarvingList)
    {
	listpos = conn::m_pTCPStarvingList->Find(pConn);

	if (listpos)
	{
	    conn::m_pTCPStarvingList->RemoveAt(listpos);
	    pConn->m_ulLastStarvingTime = 0;
	}
    }
    
    if (conn::mConnectionList->IsEmpty())
    {
	delete conn::mConnectionList;
	conn::mConnectionList = NULL;

	HX_ASSERT(!conn::m_pTCPStarvingList || conn::m_pTCPStarvingList->IsEmpty());
    }

    if (conn::m_pTCPStarvingList && conn::m_pTCPStarvingList->IsEmpty())
    {
	HX_DELETE(conn::m_pTCPStarvingList);
    }

    if (z_pConnectionListMutex)
    {
	z_pConnectionListMutex->Unlock();
    }
}

UINT32
conn::bytes_to_preparetcpread(conn* pConn)
{
    // no op. if EnforceMaxBandwidth is FALSE
    if (conn::m_ulMaxBandwidth == MAX_UINT32)
    {
	return MAX_UINT32;
    }

    UINT32	    ulCurrentTime = HX_GET_TICKCOUNT();
    UINT32	    ulBytesToRead = 0;
    LISTPOSITION    listpos = NULL;
    conn*	    pStarvingConn = NULL;

    UINT32	    ulTimeElapsed = CALCULATE_ELAPSED_TICKS(conn::m_ulTCPReadTimeStamp, ulCurrentTime);

    // return 0 bytes if the current bandwidth >= max. bandwidth
    if (ulTimeElapsed < 1000 && conn::m_ulTCPTotalBytesRead >= conn::m_ulMaxBandwidth)
    {
	goto cleanup;
    }
    // reset the attributes every 1 sec
    else if (ulTimeElapsed >= 1000)
    {
	conn::m_ulTCPReadTimeStamp = ulCurrentTime;
	conn::m_ulTCPTotalBytesRead = 0;
    }

    // remove the conn from the starving list if it has been starving to death :)
    // so other conn has chance to get the its share of bytes
    while (conn::m_pTCPStarvingList && !conn::m_pTCPStarvingList->IsEmpty())
    {
	pStarvingConn = (conn*)conn::m_pTCPStarvingList->GetHead();

	if (pStarvingConn != pConn &&
	    (CALCULATE_ELAPSED_TICKS(pStarvingConn->m_ulLastStarvingTime, ulCurrentTime) >=
	    MAX_CONN_STARVINGTIME))
	{	    
	    conn::m_pTCPStarvingList->RemoveHead();
	    pStarvingConn->m_ulLastStarvingTime = 0;
	}
	else
	{
	    break;
	}
    }

    // return 0 bytes if there is starving conn AND pConn is not the starving conn
    // at the top of the list
    if (!pStarvingConn || pStarvingConn == pConn)
    {
	// either there is no starving conn OR
	// pConn is the starving conn
	ulBytesToRead = conn::m_ulMaxBandwidth - conn::m_ulTCPTotalBytesRead;
	if (pStarvingConn)
	{
	    pStarvingConn->m_ulLastStarvingTime = 0;
	    conn::m_pTCPStarvingList->RemoveHead();
	}
    }

cleanup:

    HX_ASSERT(conn::mConnectionList);

    // if there is no bytes to read and more than 1 source
    if (ulBytesToRead == 0 && conn::mConnectionList && conn::mConnectionList->GetCount() > 1)
    {	
	if (!conn::m_pTCPStarvingList)			
	{
	    conn::m_pTCPStarvingList = new CHXSimpleList();
	}

	if (!pConn->m_ulLastStarvingTime)
	{
	    pConn->m_ulLastStarvingTime = ulCurrentTime;
	    conn::m_pTCPStarvingList->AddTail(pConn);
	}
    }

    return ulBytesToRead;
}

void
conn::bytes_to_actualtcpread(conn* pConn, UINT32 ulBytesRead)
{
    if (conn::m_ulMaxBandwidth != MAX_UINT32)
    {
	conn::m_ulTCPTotalBytesRead += ulBytesRead;
    }
}

HX_RESULT
conn::EnumerateInterfaces
    (REF(UINT32*) pulInterfaces, REF(UINT32) ulNumInterfaces)
{
    HX_RESULT theErr = HXR_OK;

    const UINT32 ulHostNameLen = 256;
 
    char pHostname[ulHostNameLen]; /* Flawfinder: ignore */
    
#ifndef _MACINTOSH
    char **pptr;
#endif

#ifdef _MACINTOSH
    return HXR_UNEXPECTED;
#endif

    theErr = init_drivers(NULL);
    if (FAILED(theErr))
    {
	// just retrun, no need to close_driver()
	return theErr;
    }

    theErr = get_host_name(pHostname, ulHostNameLen);
    if (FAILED(theErr))
    {
	goto bail;