+/** @file\r
+ Library used for sorting routines.\r
+\r
+Copyright (c) 2009, Intel Corporation\r
+All rights reserved. This program and the accompanying materials\r
+are licensed and made available under the terms and conditions of the BSD License\r
+which accompanies this distribution. The full text of the license may be found at\r
+http://opensource.org/licenses/bsd-license.php\r
+\r
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
+\r
+**/\r
+\r
+#include <Uefi.h>\r
+\r
+#include <Library/BaseLib.h>\r
+#include <Library/BaseMemoryLib.h>\r
+#include <Library/DebugLib.h>\r
+#include <Library/MemoryAllocationLib.h>\r
+#include <Library/SortLib.h> \r
+\r
+/**\r
+ Worker function for QuickSorting. This function is identical to PerformQuickSort, \r
+ except that is uses the pre-allocated buffer so the in place sorting does not need to \r
+ allocate and free buffers constantly.\r
+\r
+ Each element must be equal sized.\r
+\r
+ if BufferToSort is NULL, then ASSERT.\r
+ if CompareFunction is NULL, then ASSERT.\r
+ if Buffer is NULL, then ASSERT.\r
+\r
+ if Count is < 2 then perform no action.\r
+ if Size is < 1 then perform no action.\r
+\r
+ @param[in,out] BufferToSort on call a Buffer of (possibly sorted) elements\r
+ on return a buffer of sorted elements\r
+ @param[in] Count the number of elements in the buffer to sort\r
+ @param[in] ElementSize Size of an element in bytes\r
+ @param[in] CompareFunction The function to call to perform the comparison \r
+ of any 2 elements\r
+ @param[in] Buffer Buffer of size ElementSize for use in swapping\r
+**/\r
+VOID\r
+EFIAPI\r
+QuickSortWorker (\r
+ IN OUT VOID *BufferToSort,\r
+ IN CONST UINTN Count,\r
+ IN CONST UINTN ElementSize,\r
+ IN SORT_COMPARE CompareFunction,\r
+ IN VOID *Buffer\r
+ ){\r
+ VOID *Pivot;\r
+ UINTN LoopCount;\r
+ UINTN NextSwapLocation;\r
+\r
+ ASSERT(BufferToSort != NULL);\r
+ ASSERT(CompareFunction != NULL);\r
+ ASSERT(Buffer != NULL);\r
+\r
+ if ( Count < 2 \r
+ || ElementSize < 1\r
+ ){\r
+ return;\r
+ }\r
+\r
+ NextSwapLocation = 0;\r
+\r
+ //\r
+ // pick a pivot (we choose last element)\r
+ //\r
+ Pivot = ((UINT8*)BufferToSort+((Count-1)*ElementSize));\r
+\r
+ //\r
+ // Now get the pivot such that all on "left" are below it\r
+ // and everything "right" are above it\r
+ //\r
+ for ( LoopCount = 0\r
+ ; LoopCount < Count -1 \r
+ ; LoopCount++\r
+ ){\r
+ //\r
+ // if the element is less than the pivot\r
+ //\r
+ if (CompareFunction((VOID*)((UINT8*)BufferToSort+((LoopCount)*ElementSize)),Pivot) <= 0){\r
+ //\r
+ // swap \r
+ //\r
+ CopyMem (Buffer, (UINT8*)BufferToSort+(NextSwapLocation*ElementSize), ElementSize);\r
+ CopyMem ((UINT8*)BufferToSort+(NextSwapLocation*ElementSize), (UINT8*)BufferToSort+((LoopCount)*ElementSize), ElementSize);\r
+ CopyMem ((UINT8*)BufferToSort+((LoopCount)*ElementSize), Buffer, ElementSize);\r
+\r
+ //\r
+ // increment NextSwapLocation\r
+ // \r
+ NextSwapLocation++;\r
+ }\r
+ }\r
+ //\r
+ // swap pivot to it's final position (NextSwapLocaiton)\r
+ //\r
+ CopyMem (Buffer, Pivot, ElementSize);\r
+ CopyMem (Pivot, (UINT8*)BufferToSort+(NextSwapLocation*ElementSize), ElementSize);\r
+ CopyMem ((UINT8*)BufferToSort+(NextSwapLocation*ElementSize), Buffer, ElementSize);\r
+\r
+ //\r
+ // Now recurse on 2 paritial lists. neither of these will have the 'pivot' element \r
+ // IE list is sorted left half, pivot element, sorted right half...\r
+ //\r
+ QuickSortWorker(\r
+ BufferToSort, \r
+ NextSwapLocation, \r
+ ElementSize, \r
+ CompareFunction,\r
+ Buffer);\r
+\r
+ QuickSortWorker(\r
+ (UINT8 *)BufferToSort + (NextSwapLocation+1) * ElementSize,\r
+ Count - NextSwapLocation - 1, \r
+ ElementSize, \r
+ CompareFunction,\r
+ Buffer);\r
+\r
+ return;\r
+}\r
+/**\r
+ Function to perform a Quick Sort alogrithm on a buffer of comparable elements.\r
+\r
+ Each element must be equal sized.\r
+\r
+ if BufferToSort is NULL, then ASSERT.\r
+ if CompareFunction is NULL, then ASSERT.\r
+\r
+ if Count is < 2 then perform no action.\r
+ if Size is < 1 then perform no action.\r
+\r
+ @param[in,out] BufferToSort on call a Buffer of (possibly sorted) elements\r
+ on return a buffer of sorted elements\r
+ @param[in] Count the number of elements in the buffer to sort\r
+ @param[in] ElementSize Size of an element in bytes\r
+ @param[in] CompareFunction The function to call to perform the comparison \r
+ of any 2 elements\r
+**/\r
+VOID\r
+EFIAPI\r
+PerformQuickSort (\r
+ IN OUT VOID *BufferToSort,\r
+ IN CONST UINTN Count,\r
+ IN CONST UINTN ElementSize,\r
+ IN SORT_COMPARE CompareFunction\r
+ ){\r
+ VOID *Buffer;\r
+\r
+ ASSERT(BufferToSort != NULL);\r
+ ASSERT(CompareFunction != NULL);\r
+\r
+ Buffer = AllocatePool(ElementSize);\r
+ ASSERT(Buffer != NULL);\r
+\r
+ QuickSortWorker(\r
+ BufferToSort,\r
+ Count,\r
+ ElementSize,\r
+ CompareFunction,\r
+ Buffer);\r
+\r
+ FreePool(Buffer);\r
+ return;\r
+}\r
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