event.c

ReactOS是一些高手根据Windows XP的内核编写出的类XP。内核实现机理和API函数调用几乎相同。甚至可以兼容XP的程序。喜欢研究系统内核的人可以看一看。

/*
 * COPYRIGHT:   See COPYING in the top level directory
 * PROJECT:     ReactOS TCP/IP protocol driver
 * FILE:        transport/tcp/event.c
 * PURPOSE:     Transmission Control Protocol -- Events from oskittcp
 * PROGRAMMERS: Art Yerkes
 * REVISIONS:
 *   CSH 01/08-2000 Created
 */

#include "precomp.h"

int TCPSocketState(void *ClientData,
		   void *WhichSocket,
		   void *WhichConnection,
		   OSK_UINT NewState ) {
    PCONNECTION_ENDPOINT Connection = WhichConnection;

    TI_DbgPrint(MID_TRACE,("Flags: %c%c%c%c\n",
			   NewState & SEL_CONNECT ? 'C' : 'c',
			   NewState & SEL_READ    ? 'R' : 'r',
			   NewState & SEL_FIN     ? 'F' : 'f',
			   NewState & SEL_ACCEPT  ? 'A' : 'a'));

    TI_DbgPrint(DEBUG_TCP,("Called: NewState %x (Conn %x) (Change %x)\n",
			   NewState, Connection,
			   Connection ? Connection->State ^ NewState :
			   NewState));

    if( !Connection ) {
	TI_DbgPrint(DEBUG_TCP,("Socket closing.\n"));
	Connection = FileFindConnectionByContext( WhichSocket );
	if( !Connection )
	    return 0;
	else
	    TI_DbgPrint(DEBUG_TCP,("Found socket %x\n", Connection));
    }

    TI_DbgPrint(MID_TRACE,("Connection signalled: %d\n",
			   Connection->Signalled));

    Connection->SignalState |= NewState;
    if( !Connection->Signalled ) {
	Connection->Signalled = TRUE;
	InsertTailList( &SignalledConnections, &Connection->SignalList );
    }

    return 0;
}

void TCPPacketSendComplete( PVOID Context,
			    PNDIS_PACKET NdisPacket,
			    NDIS_STATUS NdisStatus ) {
    TI_DbgPrint(DEBUG_TCP,("called %x\n", NdisPacket));
    FreeNdisPacket(NdisPacket);
    TI_DbgPrint(DEBUG_TCP,("done\n"));
}

#define STRINGIFY(x) #x

int TCPPacketSend(void *ClientData, OSK_PCHAR data, OSK_UINT len ) {
    NDIS_STATUS NdisStatus;
    PNEIGHBOR_CACHE_ENTRY NCE;
    IP_PACKET Packet = { 0 };
    IP_ADDRESS RemoteAddress, LocalAddress;
    PIPv4_HEADER Header;

    if( *data == 0x45 ) { /* IPv4 */
	Header = (PIPv4_HEADER)data;
	LocalAddress.Type = IP_ADDRESS_V4;
	LocalAddress.Address.IPv4Address = Header->SrcAddr;
	RemoteAddress.Type = IP_ADDRESS_V4;
	RemoteAddress.Address.IPv4Address = Header->DstAddr;
    } else {
	TI_DbgPrint(MIN_TRACE,("Outgoing packet is not IPv4\n"));
	OskitDumpBuffer( data, len );
	return OSK_EINVAL;
    }

    RemoteAddress.Type = LocalAddress.Type = IP_ADDRESS_V4;

    if(!(NCE = RouteGetRouteToDestination( &RemoteAddress ))) {
	TI_DbgPrint(MIN_TRACE,("No route to %s\n", A2S(&RemoteAddress)));
	return OSK_EADDRNOTAVAIL;
    }

    NdisStatus = AllocatePacketWithBuffer( &Packet.NdisPacket, NULL,
					   MaxLLHeaderSize + len );

    if (NdisStatus != NDIS_STATUS_SUCCESS) {
	TI_DbgPrint(DEBUG_TCP, ("Error from NDIS: %08x\n", NdisStatus));
	return OSK_ENOBUFS;
    }

    GetDataPtr( Packet.NdisPacket, MaxLLHeaderSize,
		(PCHAR *)&Packet.Header, &Packet.ContigSize );

    RtlCopyMemory( Packet.Header, data, len );

    Packet.HeaderSize = sizeof(IPv4_HEADER);
    Packet.TotalSize = len;
    Packet.SrcAddr = LocalAddress;
    Packet.DstAddr = RemoteAddress;

    IPSendDatagram( &Packet, NCE, TCPPacketSendComplete, NULL );

    if( !NT_SUCCESS(NdisStatus) ) return OSK_EINVAL;
    else return 0;
}

int TCPSleep( void *ClientData, void *token, int priority, char *msg,
	      int tmio ) {
    PSLEEPING_THREAD SleepingThread;

    TI_DbgPrint(DEBUG_TCP,
		("Called TSLEEP: tok = %x, pri = %d, wmesg = %s, tmio = %x\n",
		 token, priority, msg, tmio));

    SleepingThread = PoolAllocateBuffer( sizeof( *SleepingThread ) );
    if( SleepingThread ) {
	KeInitializeEvent( &SleepingThread->Event, NotificationEvent, FALSE );
	SleepingThread->SleepToken = token;

	/* We're going to sleep and need to release the lock, otherwise
           it's impossible to re-enter oskittcp to deliver the event that's
           going to wake us */
	TcpipRecursiveMutexLeave( &TCPLock );

	TcpipAcquireFastMutex( &SleepingThreadsLock );
	InsertTailList( &SleepingThreadsList, &SleepingThread->Entry );
	TcpipReleaseFastMutex( &SleepingThreadsLock );

	TI_DbgPrint(DEBUG_TCP,("Waiting on %x\n", token));
	KeWaitForSingleObject( &SleepingThread->Event,
			       WrSuspended,
			       KernelMode,
			       TRUE,
			       NULL );

	TcpipAcquireFastMutex( &SleepingThreadsLock );
	RemoveEntryList( &SleepingThread->Entry );
	TcpipReleaseFastMutex( &SleepingThreadsLock );

	TcpipRecursiveMutexEnter( &TCPLock, TRUE );

	PoolFreeBuffer( SleepingThread );
    }
    TI_DbgPrint(DEBUG_TCP,("Waiting finished: %x\n", token));
    return 0;
}

void TCPWakeup( void *ClientData, void *token ) {
    PLIST_ENTRY Entry;
    PSLEEPING_THREAD SleepingThread;

    TcpipAcquireFastMutex( &SleepingThreadsLock );
    Entry = SleepingThreadsList.Flink;
    while( Entry != &SleepingThreadsList ) {
	SleepingThread = CONTAINING_RECORD(Entry, SLEEPING_THREAD, Entry);
	TI_DbgPrint(DEBUG_TCP,("Sleeper @ %x\n", SleepingThread));
	if( SleepingThread->SleepToken == token ) {
	    TI_DbgPrint(DEBUG_TCP,("Setting event to wake %x\n", token));
	    KeSetEvent( &SleepingThread->Event, IO_NETWORK_INCREMENT, FALSE );
	}
	Entry = Entry->Flink;
    }
    TcpipReleaseFastMutex( &SleepingThreadsLock );
}

/* Memory management routines
 *
 * By far the most requests for memory are either for 128 or 2048 byte blocks,
 * so we want to satisfy those from lookaside lists. Unfortunately, the
 * TCPFree() function doesn't pass the size of the block to be freed, so we
 * need to keep track of it ourselves. We do it by prepending each block with
 * 4 bytes, indicating if this is a 'L'arge (2048), 'S'mall (128) or 'O'ther
 * block.
 */

/* Set to some non-zero value to get a profile of memory allocation sizes */
#define MEM_PROFILE 0

#define SMALL_SIZE 128
#define LARGE_SIZE 2048

#define SIGNATURE_LARGE TAG('L','L','L','L')
#define SIGNATURE_SMALL TAG('S','S','S','S')
#define SIGNATURE_OTHER TAG('O','O','O','O')
#define TCP_TAG TAG('T','C','P',' ')

static NPAGED_LOOKASIDE_LIST LargeLookasideList;
static NPAGED_LOOKASIDE_LIST SmallLookasideList;

NTSTATUS
TCPMemStartup( void )
{
    ExInitializeNPagedLookasideList( &LargeLookasideList,
                                     NULL,
                                     NULL,
                                     0,
                                     LARGE_SIZE + sizeof( ULONG ),
                                     TCP_TAG,
                                     0 );
    ExInitializeNPagedLookasideList( &SmallLookasideList,
                                     NULL,
                                     NULL,
                                     0,
                                     SMALL_SIZE + sizeof( ULONG ),
                                     TCP_TAG,
                                     0 );

    return STATUS_SUCCESS;
}

void *TCPMalloc( void *ClientData,
		 OSK_UINT Bytes, OSK_PCHAR File, OSK_UINT Line ) {
    void *v;
    ULONG Signature;

#if 0 != MEM_PROFILE
    static OSK_UINT *Sizes = NULL, *Counts = NULL, ArrayAllocated = 0;
    static OSK_UINT ArrayUsed = 0, AllocationCount = 0;
    OSK_UINT i, NewSize, *NewArray;
    int Found;

    Found = 0;
    for ( i = 0; i < ArrayUsed && ! Found; i++ ) {
	Found = ( Sizes[i] == Bytes );
	if ( Found ) {
	    Counts[i]++;
	}
    }
    if ( ! Found ) {
	if ( ArrayAllocated <= ArrayUsed ) {
	    NewSize = ( 0 == ArrayAllocated ? 16 : 2 * ArrayAllocated );
	    NewArray = PoolAllocateBuffer( 2 * NewSize * sizeof( OSK_UINT ) );
	    if ( NULL != NewArray ) {
		if ( 0 != ArrayAllocated ) {
		    memcpy( NewArray, Sizes,
		            ArrayAllocated * sizeof( OSK_UINT ) );
		    PoolFreeBuffer( Sizes );
		    memcpy( NewArray + NewSize, Counts,
		            ArrayAllocated * sizeof( OSK_UINT ) );
		    PoolFreeBuffer( Counts );
		}
		Sizes = NewArray;
		Counts = NewArray + NewSize;
		ArrayAllocated = NewSize;
	    } else if ( 0 != ArrayAllocated ) {
		PoolFreeBuffer( Sizes );
		PoolFreeBuffer( Counts );
		ArrayAllocated = 0;
	    }
	}
	if ( ArrayUsed < ArrayAllocated ) {
	    Sizes[ArrayUsed] = Bytes;
	    Counts[ArrayUsed] = 1;
	    ArrayUsed++;
	}
    }

    if ( 0 == (++AllocationCount % MEM_PROFILE) ) {
	TI_DbgPrint(DEBUG_TCP, ("Memory allocation size profile:\n"));
	for ( i = 0; i < ArrayUsed; i++ ) {
	    TI_DbgPrint(DEBUG_TCP,
	                ("Size %4u Count %5u\n", Sizes[i], Counts[i]));
	}
	TI_DbgPrint(DEBUG_TCP, ("End of memory allocation size profile\n"));
    }
#endif /* MEM_PROFILE */

    if ( SMALL_SIZE == Bytes ) {
	v = ExAllocateFromNPagedLookasideList( &SmallLookasideList );
	Signature = SIGNATURE_SMALL;
    } else if ( LARGE_SIZE == Bytes ) {
	v = ExAllocateFromNPagedLookasideList( &LargeLookasideList );
	Signature = SIGNATURE_LARGE;
    } else {
	v = PoolAllocateBuffer( Bytes + sizeof(ULONG) );
	Signature = SIGNATURE_OTHER;
    }
    if( v ) {
	*((ULONG *) v) = Signature;
	v = (void *)((char *) v + sizeof(ULONG));
	TrackWithTag( FOURCC('f','b','s','d'), v, (PCHAR)File, Line );
    }

    return v;
}

void TCPFree( void *ClientData,
	      void *data, OSK_PCHAR File, OSK_UINT Line ) {
    ULONG Signature;

    UntrackFL( (PCHAR)File, Line, data );
    data = (void *)((char *) data - sizeof(ULONG));
    Signature = *((ULONG *) data);
    if ( SIGNATURE_SMALL == Signature ) {
	ExFreeToNPagedLookasideList( &SmallLookasideList, data );
    } else if ( SIGNATURE_LARGE == Signature ) {
	ExFreeToNPagedLookasideList( &LargeLookasideList, data );
    } else if ( SIGNATURE_OTHER == Signature ) {
	PoolFreeBuffer( data );
    } else {
	ASSERT( FALSE );
    }
}

void
TCPMemShutdown( void )
{
    ExDeleteNPagedLookasideList( &SmallLookasideList );
    ExDeleteNPagedLookasideList( &LargeLookasideList );
}