WDF ring buffer object #windows #driver

RingBuffer.c

//
// The MIT License (MIT)
//
// Copyright (c) 2013-2014 Max Truxa
//
// Permission is hereby granted, free of charge, to any person obtaining a copy of
// this software and associated documentation files (the "Software"), to deal in
// the Software without restriction, including without limitation the rights to
// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
// the Software, and to permit persons to whom the Software is furnished to do so,
// subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
// IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

/*

Module Name:

    RingBuffer.c

Abstract:

    This file contains functions to work with ring buffer objects.

Environment:

    Kernel-mode Driver Framework

*/

#include "Driver.h"


typedef struct _RINGBUFFER_CONTEXT
{
    WDFMEMORY Buffer;
    size_t    Offset;
    size_t    Length;
} RINGBUFFER_CONTEXT, * PRINGBUFFER_CONTEXT;


//
// Inline function to get a pointer to the ring buffer context memory in a type safe manner.
//
WDF_DECLARE_CONTEXT_TYPE_WITH_NAME(RINGBUFFER_CONTEXT, RingBufferGetContext)


NTSTATUS
RingBufferCreate(
    _In_opt_ PWDF_OBJECT_ATTRIBUTES Attributes,
    _In_     POOL_TYPE   PoolType,
    _In_     size_t      BufferSize,
    _Out_    RINGBUFFER* RingBuffer
    )
{
    NTSTATUS              status;
    RINGBUFFER            ringBuffer;
    PRINGBUFFER_CONTEXT   context;
    WDF_OBJECT_ATTRIBUTES attributes;
    
    if (!RingBuffer)
        WdfVerifierKeBugCheck(WDF_REQUIRED_PARAMETER_IS_NULL, 0x4, 0, (ULONG_PTR)&RingBufferCreate, 0);

    if (Attributes)
    {
        attributes = *Attributes;
        WDF_OBJECT_ATTRIBUTES_SET_CONTEXT_TYPE(&attributes, RINGBUFFER_CONTEXT);
    }
    else
    {
        WDF_OBJECT_ATTRIBUTES_INIT_CONTEXT_TYPE(&attributes, RINGBUFFER_CONTEXT);
    }

    status = WdfObjectCreate(&attributes, &ringBuffer);
    if (!NT_SUCCESS(status))
        return status;

    context = RingBufferGetContext(ringBuffer);

    WDF_OBJECT_ATTRIBUTES_INIT(&attributes);
    attributes.ParentObject = ringBuffer;

    status = WdfMemoryCreate(
        &attributes,
        PoolType,
        'GNIR',
        BufferSize,
        &context->Buffer,
        NULL
        );
    if (!NT_SUCCESS(status))
    {
        WdfObjectDelete(ringBuffer);
        return status;
    }

    *RingBuffer = ringBuffer;
    return STATUS_SUCCESS;
}


VOID
RingBufferClear(
    _In_ RINGBUFFER RingBuffer
    )
{
    PRINGBUFFER_CONTEXT context;
    
    context = RingBufferGetContext(RingBuffer);

    context->Offset = 0;
    context->Length = 0;
}


NTSTATUS
RingBufferAppend(
    _In_ RINGBUFFER RingBuffer,
    _In_ WDFMEMORY  SourceMemory,
    _In_ size_t     SourceOffset,
    _In_ size_t     NumberOfBytesToAppend,
    _In_ BOOLEAN    Overwrite
    )
{
    PRINGBUFFER_CONTEXT context;
    PUCHAR source;
    size_t sourceSize;
    PUCHAR buffer;
    size_t bufferSize;
    size_t offset;
    size_t length;

    if (Overwrite)
        return STATUS_NOT_IMPLEMENTED;
    
    context = RingBufferGetContext(RingBuffer);

    source = (PUCHAR)WdfMemoryGetBuffer(SourceMemory,    &sourceSize);
    buffer = (PUCHAR)WdfMemoryGetBuffer(context->Buffer, &bufferSize);

    // Validate source offset
    if (SourceOffset > sourceSize)
        return STATUS_BUFFER_OVERFLOW;

    // Apply source offset
    source     += SourceOffset;
    sourceSize -= SourceOffset;
    
    // Validate number of bytes to copy
    if (NumberOfBytesToAppend > sourceSize)
        return STATUS_BUFFER_OVERFLOW;
    if (NumberOfBytesToAppend > (bufferSize - context->Length))
        return STATUS_BUFFER_TOO_SMALL;
    
    while (NumberOfBytesToAppend)
    {
        offset = (context->Offset + context->Length) % bufferSize;
        length = min(bufferSize - offset, NumberOfBytesToAppend);

        RtlCopyMemory(buffer + offset, source, length);

        context->Length       += length;
        NumberOfBytesToAppend -= length;
        source                += length;
    }

    return STATUS_SUCCESS;
}


NTSTATUS
RingBufferRemove(
    _In_  RINGBUFFER RingBuffer,
    _Out_ WDFMEMORY  DestinationMemory,
    _In_  size_t     DestinationOffset,
    _In_  size_t     NumberOfBytesToRemove,
    _Out_ size_t*    NumberOfBytesRemoved
    )
{
    PRINGBUFFER_CONTEXT context;
    PUCHAR destination;
    size_t destinationSize;
    PUCHAR buffer;
    size_t bufferSize;
    size_t length;
    size_t numberOfBytesRemoved;

    if (NumberOfBytesRemoved)
        *NumberOfBytesRemoved = 0;

    context = RingBufferGetContext(RingBuffer);

    destination = (PUCHAR)WdfMemoryGetBuffer(DestinationMemory, &destinationSize);
    buffer      = (PUCHAR)WdfMemoryGetBuffer(context->Buffer,   &bufferSize);

    // Validate destination offset
    if (DestinationOffset > destinationSize)
        return STATUS_BUFFER_TOO_SMALL;

    // Apply destination offset
    destination     += DestinationOffset;
    destinationSize -= DestinationOffset;
    
    // Validate number of bytes to copy
    if (NumberOfBytesToRemove > destinationSize)
        return STATUS_BUFFER_TOO_SMALL;
    
    numberOfBytesRemoved = 0;
    
    while (NumberOfBytesToRemove && context->Length)
    {
        length = min(bufferSize - context->Offset, NumberOfBytesToRemove);
        if (length > context->Length)
            length = context->Length;

        RtlCopyMemory(destination, buffer + context->Offset, length);

        context->Offset = (context->Offset + length) % bufferSize;
        context->Length       -= length;
        NumberOfBytesToRemove -= length;
        destination           += length;
        numberOfBytesRemoved  += length;
    }

    if (NumberOfBytesRemoved)
        *NumberOfBytesRemoved = numberOfBytesRemoved;

    return STATUS_SUCCESS;
}


size_t
RingBufferGetLength(
    _In_  RINGBUFFER RingBuffer
    )
{
    return RingBufferGetContext(RingBuffer)->Length;
}

RingBuffer.h

//
// The MIT License (MIT)
//
// Copyright (c) 2013-2014 Max Truxa
//
// Permission is hereby granted, free of charge, to any person obtaining a copy of
// this software and associated documentation files (the "Software"), to deal in
// the Software without restriction, including without limitation the rights to
// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
// the Software, and to permit persons to whom the Software is furnished to do so,
// subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
// IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

/*

Module Name:

    RingBuffer.h

Abstract:

    This file contains the definitions for ring buffer objects.

Environment:

    Kernel-mode Driver Framework

*/


DECLARE_HANDLE(RINGBUFFER);


NTSTATUS
RingBufferCreate(
    _In_opt_ PWDF_OBJECT_ATTRIBUTES Attributes,
    _In_     POOL_TYPE   PoolType,
    _In_     size_t      BufferSize,
    _Out_    RINGBUFFER* RingBuffer
    );

VOID
RingBufferClear(
    _In_ RINGBUFFER RingBuffer
    );

NTSTATUS
RingBufferAppend(
    _In_ RINGBUFFER RingBuffer,
    _In_ WDFMEMORY  SourceMemory,
    _In_ size_t     SourceOffset,
    _In_ size_t     NumberOfBytesToAppend,
    _In_ BOOLEAN    Overwrite
    );

NTSTATUS
RingBufferRemove(
    _In_  RINGBUFFER RingBuffer,
    _Out_ WDFMEMORY  DestinationMemory,
    _In_  size_t     DestinationOffset,
    _In_  size_t     NumberOfBytesToRemove,
    _Out_ size_t*    NumberOfBytesRemoved
    );

size_t
RingBufferGetLength(
    _In_  RINGBUFFER RingBuffer
    );