rawchan.c File Reference

#include "sacdrv.h"

Include dependency graph for rawchan.c:

Go to the source code of this file.

Functions
NTSTATUS NTAPI	RawChannelCreate (IN PSAC_CHANNEL Channel)
NTSTATUS NTAPI	RawChannelDestroy (IN PSAC_CHANNEL Channel)
FORCEINLINE BOOLEAN	ChannelHasNewOBufferData (IN PSAC_CHANNEL Channel)
NTSTATUS NTAPI	RawChannelORead (IN PSAC_CHANNEL Channel, IN PCHAR Buffer, IN ULONG BufferSize, OUT PULONG ByteCount)
NTSTATUS NTAPI	RawChannelOEcho (IN PSAC_CHANNEL Channel, IN PCHAR String, IN ULONG Length)
NTSTATUS NTAPI	RawChannelOWrite2 (IN PSAC_CHANNEL Channel, IN PCHAR String, IN ULONG Size)
NTSTATUS NTAPI	RawChannelOFlush (IN PSAC_CHANNEL Channel)
NTSTATUS NTAPI	RawChannelOWrite (IN PSAC_CHANNEL Channel, IN PCHAR String, IN ULONG Length)
ULONG NTAPI	RawChannelGetIBufferIndex (IN PSAC_CHANNEL Channel)
VOID NTAPI	RawChannelSetIBufferIndex (IN PSAC_CHANNEL Channel, IN ULONG BufferIndex)
NTSTATUS NTAPI	RawChannelIRead (IN PSAC_CHANNEL Channel, IN PCHAR Buffer, IN ULONG BufferSize, IN PULONG ReturnBufferSize)
NTSTATUS NTAPI	RawChannelIBufferIsFull (IN PSAC_CHANNEL Channel, OUT PBOOLEAN BufferStatus)
ULONG NTAPI	RawChannelIBufferLength (IN PSAC_CHANNEL Channel)
WCHAR NTAPI	RawChannelIReadLast (IN PSAC_CHANNEL Channel)
NTSTATUS NTAPI	RawChannelIWrite (IN PSAC_CHANNEL Channel, IN PCHAR Buffer, IN ULONG BufferSize)

Function Documentation

ChannelHasNewOBufferData()

FORCEINLINE BOOLEAN ChannelHasNewOBufferData

(

IN PSAC_CHANNEL

Channel

)

Definition at line 51 of file rawchan.c.

{
    return Channel->ChannelHasNewOBufferData;
}

Referenced by ChanMgrReapChannels(), RawChannelOFlush(), RawChannelORead(), and RawChannelOWrite2().

RawChannelCreate()

NTSTATUS NTAPI RawChannelCreate

(

IN PSAC_CHANNEL

Channel

)

Definition at line 17 of file rawchan.c.

{
    CHECK_PARAMETER(Channel);
 
    /* Allocate the output buffer */
    Channel->OBuffer = SacAllocatePool(SAC_RAW_OBUFFER_SIZE, GLOBAL_BLOCK_TAG);
    CHECK_ALLOCATION(Channel->OBuffer);
 
    /* Allocate the input buffer */
    Channel->IBuffer = SacAllocatePool(SAC_RAW_IBUFFER_SIZE, GLOBAL_BLOCK_TAG);
    CHECK_ALLOCATION(Channel->IBuffer);
 
    /* Reset all flags and return success */
    Channel->OBufferIndex = 0;
    Channel->OBufferFirstGoodIndex = 0;
    Channel->ChannelHasNewIBufferData = FALSE;
    Channel->ChannelHasNewOBufferData = FALSE;
    return STATUS_SUCCESS;
}

Referenced by ChannelInitializeVTable().

RawChannelDestroy()

NTSTATUS NTAPI RawChannelDestroy

(

IN PSAC_CHANNEL

Channel

)

Definition at line 39 of file rawchan.c.

{
    CHECK_PARAMETER(Channel);
 
    /* Free the buffer and then destroy the channel */
    if (Channel->OBuffer) SacFreePool(Channel->OBuffer);
    if (Channel->IBuffer) SacFreePool(Channel->IBuffer);
    return ChannelDestroy(Channel);
}

Referenced by ChannelInitializeVTable().

RawChannelGetIBufferIndex()

ULONG NTAPI RawChannelGetIBufferIndex

(

IN PSAC_CHANNEL

Channel

)

Definition at line 212 of file rawchan.c.

{
    ASSERT(Channel);
    ASSERT(Channel->IBufferIndex < SAC_RAW_IBUFFER_SIZE);
 
    /* Return the current buffer index */
    return Channel->IBufferIndex;
}

Referenced by RawChannelIBufferIsFull(), RawChannelIBufferLength(), RawChannelIRead(), RawChannelIReadLast(), and RawChannelIWrite().

RawChannelIBufferIsFull()

NTSTATUS NTAPI RawChannelIBufferIsFull	(	IN PSAC_CHANNEL	Channel,
		OUT PBOOLEAN	BufferStatus
	)

Definition at line 297 of file rawchan.c.

{
    CHECK_PARAMETER1(Channel);
    CHECK_PARAMETER2(BufferStatus);
 
    /* If the index is beyond the length, the buffer must be full */
    *BufferStatus = RawChannelGetIBufferIndex(Channel) > SAC_RAW_IBUFFER_SIZE;
    return STATUS_SUCCESS;
}

Referenced by ChannelInitializeVTable(), and RawChannelIWrite().

RawChannelIBufferLength()

ULONG NTAPI RawChannelIBufferLength

(

IN PSAC_CHANNEL

Channel

)

Definition at line 310 of file rawchan.c.

{
    ASSERT(Channel);
 
    /* The index is the current length (since we're 0-based) */
    return RawChannelGetIBufferIndex(Channel);
}

Referenced by ChannelInitializeVTable().

RawChannelIRead()

NTSTATUS NTAPI RawChannelIRead	(	IN PSAC_CHANNEL	Channel,
		IN PCHAR	Buffer,
		IN ULONG	BufferSize,
		IN PULONG	ReturnBufferSize
	)

Definition at line 246 of file rawchan.c.

{
    ULONG CopyChars;
    CHECK_PARAMETER1(Channel);
    CHECK_PARAMETER2(Buffer);
    CHECK_PARAMETER_WITH_STATUS(BufferSize > 0, STATUS_INVALID_BUFFER_SIZE);
 
    /* Assume failure */
    *ReturnBufferSize = 0;
 
    /* Check how many bytes are in the buffer */
    if (Channel->ChannelInputBufferLength(Channel) == 0)
    {
        /* Apparently nothing. Make sure the flag indicates so too */
        ASSERT(ChannelHasNewIBufferData(Channel) == FALSE);
    }
    else
    {
        /* Use the smallest number of bytes either in the buffer or requested */
        CopyChars = min(Channel->ChannelInputBufferLength(Channel), BufferSize);
        ASSERT(CopyChars <= Channel->ChannelInputBufferLength(Channel));
 
        /* Copy them into the caller's buffer */
        RtlCopyMemory(Buffer, Channel->IBuffer, CopyChars);
 
        /* Update the channel's index past the copied (read) bytes */
        RawChannelSetIBufferIndex(Channel,
                                  RawChannelGetIBufferIndex(Channel) - CopyChars);
 
        /* Are there still bytes that haven't been read yet? */
        if (Channel->ChannelInputBufferLength(Channel))
        {
            /* Shift them up in the buffer */
            RtlMoveMemory(Channel->IBuffer,
                          &Channel->IBuffer[CopyChars],
                          Channel->ChannelInputBufferLength(Channel));
        }
 
        /* Return the number of bytes we actually copied */
        *ReturnBufferSize = CopyChars;
    }
 
    /* Return success */
    return STATUS_SUCCESS;
}

Referenced by ChannelInitializeVTable().

RawChannelIReadLast()

WCHAR NTAPI RawChannelIReadLast

(

IN PSAC_CHANNEL

Channel

)

Definition at line 320 of file rawchan.c.

{
    UCHAR LastChar = 0;
    ASSERT(Channel);
 
    /* Check if there's anything to read in the buffer */
    if (Channel->ChannelInputBufferLength(Channel))
    {
        /* Go back one character */
        RawChannelSetIBufferIndex(Channel,
                                  RawChannelGetIBufferIndex(Channel) - 1);
 
        /* Read it, and clear its current value */
        LastChar = Channel->IBuffer[RawChannelGetIBufferIndex(Channel)];
        Channel->IBuffer[RawChannelGetIBufferIndex(Channel)] = ANSI_NULL;
    }
 
    /* Return the last character */
    return LastChar;
}

Referenced by ChannelInitializeVTable().

RawChannelIWrite()

NTSTATUS NTAPI RawChannelIWrite	(	IN PSAC_CHANNEL	Channel,
		IN PCHAR	Buffer,
		IN ULONG	BufferSize
	)

Definition at line 343 of file rawchan.c.

{
    NTSTATUS Status;
    BOOLEAN IsFull;
    ULONG Index;
    CHECK_PARAMETER1(Channel);
    CHECK_PARAMETER2(Buffer);
    CHECK_PARAMETER_WITH_STATUS(BufferSize > 0, STATUS_INVALID_BUFFER_SIZE);
 
    /* First, check if the input buffer still has space */
    Status = RawChannelIBufferIsFull(Channel, &IsFull);
    if (!NT_SUCCESS(Status)) return Status;
    if (IsFull) return STATUS_UNSUCCESSFUL;
 
    /* Get the current buffer index */
    Index = RawChannelGetIBufferIndex(Channel);
    if ((SAC_RAW_IBUFFER_SIZE - Index) < BufferSize)
    {
        return STATUS_INSUFFICIENT_RESOURCES;
    }
 
    /* Copy the new data */
    RtlCopyMemory(&Channel->IBuffer[Index], Buffer, BufferSize);
 
    /* Update the index */
    RawChannelSetIBufferIndex(Channel, BufferSize + Index);
 
    /* Signal the event, if one was set */
    if (Channel->Flags & SAC_CHANNEL_FLAG_HAS_NEW_DATA_EVENT)
    {
        ChannelSetEvent(Channel, HasNewDataEvent);
    }
 
    /* All done */
    return STATUS_SUCCESS;
}

Referenced by ChannelInitializeVTable().

RawChannelOEcho()

NTSTATUS NTAPI RawChannelOEcho	(	IN PSAC_CHANNEL	Channel,
		IN PCHAR	String,
		IN ULONG	Length
	)

Definition at line 115 of file rawchan.c.

{
    NTSTATUS Status = STATUS_SUCCESS;
 
    CHECK_PARAMETER1(Channel);
    CHECK_PARAMETER2(String);
 
    if (Length)
    {
        Status = ConMgrWriteData(Channel, String, Length);
        if (NT_SUCCESS(Status)) ConMgrFlushData(Channel);
    }
 
    return Status;
}

Referenced by ChannelInitializeVTable(), and RawChannelOWrite().

RawChannelOFlush()

NTSTATUS NTAPI RawChannelOFlush

(

IN PSAC_CHANNEL

Channel

)

Definition at line 172 of file rawchan.c.

{
    NTSTATUS Status;
    ULONG ByteCount;
    CHAR Dummy;
    CHECK_PARAMETER1(Channel);
 
    while (ChannelHasNewOBufferData(Channel))
    {
        Status = RawChannelORead(Channel, &Dummy, sizeof(Dummy), &ByteCount);
        if (!NT_SUCCESS(Status)) return Status;
 
        CHECK_PARAMETER_WITH_STATUS(ByteCount == 1, STATUS_UNSUCCESSFUL);
 
        Status = ConMgrWriteData(Channel, &Dummy, sizeof(Dummy));
        if (!NT_SUCCESS(Status)) return Status;
    }
 
    return ConMgrFlushData(Channel);
}

Referenced by ChannelInitializeVTable().

RawChannelORead()

NTSTATUS NTAPI RawChannelORead	(	IN PSAC_CHANNEL	Channel,
		IN PCHAR	Buffer,
		IN ULONG	BufferSize,
		OUT PULONG	ByteCount
	)

Definition at line 58 of file rawchan.c.

{
    NTSTATUS Status;
    ULONG NextIndex;
 
    CHECK_PARAMETER1(Channel);
    CHECK_PARAMETER2(Buffer);
    CHECK_PARAMETER3(BufferSize > 0);
    CHECK_PARAMETER4(ByteCount);
 
    *ByteCount = 0;
 
    if (ChannelHasNewOBufferData(Channel))
    {
        Status = STATUS_SUCCESS;
 
        while (TRUE)
        {
            Buffer[(*ByteCount)++] = Channel->OBuffer[Channel->OBufferFirstGoodIndex];
 
            NextIndex = (Channel->OBufferFirstGoodIndex + 1) & (SAC_OBUFFER_SIZE - 1);
            Channel->OBufferFirstGoodIndex = NextIndex;
 
            if (NextIndex == Channel->OBufferIndex)
            {
                _InterlockedExchange(&Channel->ChannelHasNewOBufferData, 0);
                break;
            }
 
            ASSERT(*ByteCount > 0);
 
            if (*ByteCount >= BufferSize) break;
        }
    }
    else
    {
        Status = STATUS_NO_DATA_DETECTED;
    }
 
    if (Channel->OBufferFirstGoodIndex == Channel->OBufferIndex)
    {
        ASSERT(ChannelHasNewOBufferData(Channel) == FALSE);
    }
 
    if (ChannelHasNewOBufferData(Channel) == FALSE)
    {
        ASSERT(Channel->OBufferFirstGoodIndex == Channel->OBufferIndex);
    }
 
    return Status;
}

Referenced by ChannelInitializeVTable(), and RawChannelOFlush().

RawChannelOWrite()

NTSTATUS NTAPI RawChannelOWrite	(	IN PSAC_CHANNEL	Channel,
		IN PCHAR	String,
		IN ULONG	Length
	)

Definition at line 195 of file rawchan.c.

{
    CHECK_PARAMETER1(Channel);
    CHECK_PARAMETER2(String);
 
    if ((ConMgrIsWriteEnabled(Channel)) && (Channel->WriteEnabled))
    {
        return RawChannelOEcho(Channel, String, Length);
    }
 
    return RawChannelOWrite2(Channel, String, Length);
}

Referenced by ChannelInitializeVTable().

RawChannelOWrite2()

NTSTATUS NTAPI RawChannelOWrite2	(	IN PSAC_CHANNEL	Channel,
		IN PCHAR	String,
		IN ULONG	Size
	)

Definition at line 135 of file rawchan.c.

{
    BOOLEAN Overflow;
    ULONG i, NextIndex;
 
    CHECK_PARAMETER1(Channel);
    CHECK_PARAMETER2(String);
 
    Overflow = FALSE;
 
    for (i = 0; i < Size; i++)
    {
        if ((Channel->OBufferIndex == Channel->OBufferFirstGoodIndex) &&
            ((i) || (ChannelHasNewOBufferData(Channel))))
        {
            Overflow = TRUE;
        }
 
        ASSERT(Channel->OBufferIndex < SAC_RAW_OBUFFER_SIZE);
 
        Channel->OBuffer[Channel->OBufferIndex] = String[i];
 
        NextIndex = (Channel->OBufferIndex + 1) & (SAC_RAW_OBUFFER_SIZE - 1);
        Channel->OBufferIndex = NextIndex;
 
        if (Overflow) Channel->OBufferFirstGoodIndex = NextIndex;
    }
 
    _InterlockedExchange(&Channel->ChannelHasNewOBufferData, 1);
 
    return STATUS_SUCCESS;
}

Referenced by RawChannelOWrite().

RawChannelSetIBufferIndex()

VOID NTAPI RawChannelSetIBufferIndex	(	IN PSAC_CHANNEL	Channel,
		IN ULONG	BufferIndex
	)

Definition at line 223 of file rawchan.c.

{
    NTSTATUS Status;
    ASSERT(Channel);
    ASSERT(Channel->IBufferIndex < SAC_RAW_IBUFFER_SIZE);
 
    /* Set the new index, and if it's not zero, it means we have data */
    Channel->IBufferIndex = BufferIndex;
    _InterlockedExchange(&Channel->ChannelHasNewIBufferData, BufferIndex != 0);
 
    /* If we have new data, and an event has been registered... */
    if (!(Channel->IBufferIndex) &&
        (Channel->Flags & SAC_CHANNEL_FLAG_HAS_NEW_DATA_EVENT))
    {
        /* Go ahead and signal it */
        ChannelClearEvent(Channel, HasNewDataEvent);
        UNREFERENCED_PARAMETER(Status);
    }
}

Referenced by RawChannelIRead(), RawChannelIReadLast(), and RawChannelIWrite().