diff options
Diffstat (limited to 'FreeRTOS-Labs/Source/FreeRTOS-Plus-TCP/FreeRTOS_Stream_Buffer.c')
| -rw-r--r-- | FreeRTOS-Labs/Source/FreeRTOS-Plus-TCP/FreeRTOS_Stream_Buffer.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/FreeRTOS-Labs/Source/FreeRTOS-Plus-TCP/FreeRTOS_Stream_Buffer.c b/FreeRTOS-Labs/Source/FreeRTOS-Plus-TCP/FreeRTOS_Stream_Buffer.c new file mode 100644 index 000000000..994da7384 --- /dev/null +++ b/FreeRTOS-Labs/Source/FreeRTOS-Plus-TCP/FreeRTOS_Stream_Buffer.c @@ -0,0 +1,199 @@ +/*
+ * FreeRTOS+TCP 191100 experimental
+ * Copyright (C) 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * 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.
+ *
+ * http://aws.amazon.com/freertos
+ * http://www.FreeRTOS.org
+ */
+
+/* Standard includes. */
+#include <stdint.h>
+
+/* FreeRTOS includes. */
+#include "FreeRTOS.h"
+#include "task.h"
+#include "semphr.h"
+
+/* FreeRTOS+TCP includes. */
+#include "FreeRTOS_UDP_IP.h"
+#include "FreeRTOS_IP.h"
+#include "FreeRTOS_Sockets.h"
+#include "FreeRTOS_IP_Private.h"
+
+/*
+ * uxStreamBufferAdd( )
+ * Adds data to a stream buffer. If uxOffset > 0, data will be written at
+ * an offset from uxHead while uxHead will not be moved yet. This possibility
+ * will be used when TCP data is received while earlier data is still missing.
+ * If 'pucData' equals NULL, the function is called to advance 'uxHead' only.
+ */
+size_t uxStreamBufferAdd( StreamBuffer_t *pxBuffer, size_t uxOffset, const uint8_t *pucData, size_t uxCount )
+{
+size_t uxSpace, uxNextHead, uxFirst;
+
+ uxSpace = uxStreamBufferGetSpace( pxBuffer );
+
+ /* If uxOffset > 0, items can be placed in front of uxHead */
+ if( uxSpace > uxOffset )
+ {
+ uxSpace -= uxOffset;
+ }
+ else
+ {
+ uxSpace = 0u;
+ }
+
+ /* The number of bytes that can be written is the minimum of the number of
+ bytes requested and the number available. */
+ uxCount = FreeRTOS_min_uint32( uxSpace, uxCount );
+
+ if( uxCount != 0u )
+ {
+ uxNextHead = pxBuffer->uxHead;
+
+ if( uxOffset != 0u )
+ {
+ /* ( uxOffset > 0 ) means: write in front if the uxHead marker */
+ uxNextHead += uxOffset;
+ if( uxNextHead >= pxBuffer->LENGTH )
+ {
+ uxNextHead -= pxBuffer->LENGTH;
+ }
+ }
+
+ if( pucData != NULL )
+ {
+ /* Calculate the number of bytes that can be added in the first
+ write - which may be less than the total number of bytes that need
+ to be added if the buffer will wrap back to the beginning. */
+ uxFirst = FreeRTOS_min_uint32( pxBuffer->LENGTH - uxNextHead, uxCount );
+
+ /* Write as many bytes as can be written in the first write. */
+ memcpy( ( void* ) ( pxBuffer->ucArray + uxNextHead ), pucData, uxFirst );
+
+ /* If the number of bytes written was less than the number that
+ could be written in the first write... */
+ if( uxCount > uxFirst )
+ {
+ /* ...then write the remaining bytes to the start of the
+ buffer. */
+ memcpy( ( void * )pxBuffer->ucArray, pucData + uxFirst, uxCount - uxFirst );
+ }
+ }
+
+ if( uxOffset == 0u )
+ {
+ /* ( uxOffset == 0 ) means: write at uxHead position */
+ uxNextHead += uxCount;
+ if( uxNextHead >= pxBuffer->LENGTH )
+ {
+ uxNextHead -= pxBuffer->LENGTH;
+ }
+ pxBuffer->uxHead = uxNextHead;
+ }
+
+ if( xStreamBufferLessThenEqual( pxBuffer, pxBuffer->uxFront, uxNextHead ) != pdFALSE )
+ {
+ /* Advance the front pointer */
+ pxBuffer->uxFront = uxNextHead;
+ }
+ }
+
+ return uxCount;
+}
+/*-----------------------------------------------------------*/
+
+/*
+ * uxStreamBufferGet( )
+ * 'uxOffset' can be used to read data located at a certain offset from 'lTail'.
+ * If 'pucData' equals NULL, the function is called to advance 'lTail' only.
+ * if 'xPeek' is pdTRUE, or if 'uxOffset' is non-zero, the 'lTail' pointer will
+ * not be advanced.
+ */
+size_t uxStreamBufferGet( StreamBuffer_t *pxBuffer, size_t uxOffset, uint8_t *pucData, size_t uxMaxCount, BaseType_t xPeek )
+{
+size_t uxSize, uxCount, uxFirst, uxNextTail;
+
+ /* How much data is available? */
+ uxSize = uxStreamBufferGetSize( pxBuffer );
+
+ if( uxSize > uxOffset )
+ {
+ uxSize -= uxOffset;
+ }
+ else
+ {
+ uxSize = 0u;
+ }
+
+ /* Use the minimum of the wanted bytes and the available bytes. */
+ uxCount = FreeRTOS_min_uint32( uxSize, uxMaxCount );
+
+ if( uxCount > 0u )
+ {
+ uxNextTail = pxBuffer->uxTail;
+
+ if( uxOffset != 0u )
+ {
+ uxNextTail += uxOffset;
+ if( uxNextTail >= pxBuffer->LENGTH )
+ {
+ uxNextTail -= pxBuffer->LENGTH;
+ }
+ }
+
+ if( pucData != NULL )
+ {
+ /* Calculate the number of bytes that can be read - which may be
+ less than the number wanted if the data wraps around to the start of
+ the buffer. */
+ uxFirst = FreeRTOS_min_uint32( pxBuffer->LENGTH - uxNextTail, uxCount );
+
+ /* Obtain the number of bytes it is possible to obtain in the first
+ read. */
+ memcpy( pucData, pxBuffer->ucArray + uxNextTail, uxFirst );
+
+ /* If the total number of wanted bytes is greater than the number
+ that could be read in the first read... */
+ if( uxCount > uxFirst )
+ {
+ /*...then read the remaining bytes from the start of the buffer. */
+ memcpy( pucData + uxFirst, pxBuffer->ucArray, uxCount - uxFirst );
+ }
+ }
+
+ if( ( xPeek == pdFALSE ) && ( uxOffset == 0UL ) )
+ {
+ /* Move the tail pointer to effecively remove the data read from
+ the buffer. */
+ uxNextTail += uxCount;
+
+ if( uxNextTail >= pxBuffer->LENGTH )
+ {
+ uxNextTail -= pxBuffer->LENGTH;
+ }
+
+ pxBuffer->uxTail = uxNextTail;
+ }
+ }
+
+ return uxCount;
+}
+
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