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4983ca93 | 1 | /** @file\r |
2 | Library used for sorting routines.\r | |
3 | \r | |
4 | Copyright (c) 2009, Intel Corporation\r | |
5 | All rights reserved. This program and the accompanying materials\r | |
6 | are licensed and made available under the terms and conditions of the BSD License\r | |
7 | which accompanies this distribution. The full text of the license may be found at\r | |
8 | http://opensource.org/licenses/bsd-license.php\r | |
9 | \r | |
10 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
11 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
12 | \r | |
13 | **/\r | |
14 | \r | |
15 | #include <Uefi.h>\r | |
16 | \r | |
17 | #include <Library/BaseLib.h>\r | |
18 | #include <Library/BaseMemoryLib.h>\r | |
19 | #include <Library/DebugLib.h>\r | |
20 | #include <Library/MemoryAllocationLib.h>\r | |
21 | #include <Library/SortLib.h> \r | |
22 | \r | |
23 | /**\r | |
24 | Worker function for QuickSorting. This function is identical to PerformQuickSort, \r | |
25 | except that is uses the pre-allocated buffer so the in place sorting does not need to \r | |
26 | allocate and free buffers constantly.\r | |
27 | \r | |
28 | Each element must be equal sized.\r | |
29 | \r | |
30 | if BufferToSort is NULL, then ASSERT.\r | |
31 | if CompareFunction is NULL, then ASSERT.\r | |
32 | if Buffer is NULL, then ASSERT.\r | |
33 | \r | |
34 | if Count is < 2 then perform no action.\r | |
35 | if Size is < 1 then perform no action.\r | |
36 | \r | |
37 | @param[in,out] BufferToSort on call a Buffer of (possibly sorted) elements\r | |
38 | on return a buffer of sorted elements\r | |
39 | @param[in] Count the number of elements in the buffer to sort\r | |
40 | @param[in] ElementSize Size of an element in bytes\r | |
41 | @param[in] CompareFunction The function to call to perform the comparison \r | |
42 | of any 2 elements\r | |
43 | @param[in] Buffer Buffer of size ElementSize for use in swapping\r | |
44 | **/\r | |
45 | VOID\r | |
46 | EFIAPI\r | |
47 | QuickSortWorker (\r | |
48 | IN OUT VOID *BufferToSort,\r | |
49 | IN CONST UINTN Count,\r | |
50 | IN CONST UINTN ElementSize,\r | |
51 | IN SORT_COMPARE CompareFunction,\r | |
52 | IN VOID *Buffer\r | |
125c2cf4 | 53 | )\r |
54 | {\r | |
4983ca93 | 55 | VOID *Pivot;\r |
56 | UINTN LoopCount;\r | |
57 | UINTN NextSwapLocation;\r | |
58 | \r | |
59 | ASSERT(BufferToSort != NULL);\r | |
60 | ASSERT(CompareFunction != NULL);\r | |
61 | ASSERT(Buffer != NULL);\r | |
62 | \r | |
63 | if ( Count < 2 \r | |
64 | || ElementSize < 1\r | |
65 | ){\r | |
66 | return;\r | |
67 | }\r | |
68 | \r | |
69 | NextSwapLocation = 0;\r | |
70 | \r | |
71 | //\r | |
72 | // pick a pivot (we choose last element)\r | |
73 | //\r | |
74 | Pivot = ((UINT8*)BufferToSort+((Count-1)*ElementSize));\r | |
75 | \r | |
76 | //\r | |
77 | // Now get the pivot such that all on "left" are below it\r | |
78 | // and everything "right" are above it\r | |
79 | //\r | |
80 | for ( LoopCount = 0\r | |
81 | ; LoopCount < Count -1 \r | |
82 | ; LoopCount++\r | |
83 | ){\r | |
84 | //\r | |
85 | // if the element is less than the pivot\r | |
86 | //\r | |
87 | if (CompareFunction((VOID*)((UINT8*)BufferToSort+((LoopCount)*ElementSize)),Pivot) <= 0){\r | |
88 | //\r | |
89 | // swap \r | |
90 | //\r | |
91 | CopyMem (Buffer, (UINT8*)BufferToSort+(NextSwapLocation*ElementSize), ElementSize);\r | |
92 | CopyMem ((UINT8*)BufferToSort+(NextSwapLocation*ElementSize), (UINT8*)BufferToSort+((LoopCount)*ElementSize), ElementSize);\r | |
93 | CopyMem ((UINT8*)BufferToSort+((LoopCount)*ElementSize), Buffer, ElementSize);\r | |
94 | \r | |
95 | //\r | |
96 | // increment NextSwapLocation\r | |
97 | // \r | |
98 | NextSwapLocation++;\r | |
99 | }\r | |
100 | }\r | |
101 | //\r | |
102 | // swap pivot to it's final position (NextSwapLocaiton)\r | |
103 | //\r | |
104 | CopyMem (Buffer, Pivot, ElementSize);\r | |
105 | CopyMem (Pivot, (UINT8*)BufferToSort+(NextSwapLocation*ElementSize), ElementSize);\r | |
106 | CopyMem ((UINT8*)BufferToSort+(NextSwapLocation*ElementSize), Buffer, ElementSize);\r | |
107 | \r | |
108 | //\r | |
109 | // Now recurse on 2 paritial lists. neither of these will have the 'pivot' element \r | |
110 | // IE list is sorted left half, pivot element, sorted right half...\r | |
111 | //\r | |
112 | QuickSortWorker(\r | |
113 | BufferToSort, \r | |
114 | NextSwapLocation, \r | |
115 | ElementSize, \r | |
116 | CompareFunction,\r | |
117 | Buffer);\r | |
118 | \r | |
119 | QuickSortWorker(\r | |
120 | (UINT8 *)BufferToSort + (NextSwapLocation+1) * ElementSize,\r | |
121 | Count - NextSwapLocation - 1, \r | |
122 | ElementSize, \r | |
123 | CompareFunction,\r | |
124 | Buffer);\r | |
125 | \r | |
126 | return;\r | |
127 | }\r | |
128 | /**\r | |
129 | Function to perform a Quick Sort alogrithm on a buffer of comparable elements.\r | |
130 | \r | |
131 | Each element must be equal sized.\r | |
132 | \r | |
133 | if BufferToSort is NULL, then ASSERT.\r | |
134 | if CompareFunction is NULL, then ASSERT.\r | |
135 | \r | |
136 | if Count is < 2 then perform no action.\r | |
137 | if Size is < 1 then perform no action.\r | |
138 | \r | |
139 | @param[in,out] BufferToSort on call a Buffer of (possibly sorted) elements\r | |
140 | on return a buffer of sorted elements\r | |
141 | @param[in] Count the number of elements in the buffer to sort\r | |
142 | @param[in] ElementSize Size of an element in bytes\r | |
143 | @param[in] CompareFunction The function to call to perform the comparison \r | |
144 | of any 2 elements\r | |
145 | **/\r | |
146 | VOID\r | |
147 | EFIAPI\r | |
148 | PerformQuickSort (\r | |
149 | IN OUT VOID *BufferToSort,\r | |
150 | IN CONST UINTN Count,\r | |
151 | IN CONST UINTN ElementSize,\r | |
152 | IN SORT_COMPARE CompareFunction\r | |
125c2cf4 | 153 | )\r |
154 | {\r | |
4983ca93 | 155 | VOID *Buffer;\r |
156 | \r | |
157 | ASSERT(BufferToSort != NULL);\r | |
158 | ASSERT(CompareFunction != NULL);\r | |
159 | \r | |
160 | Buffer = AllocatePool(ElementSize);\r | |
161 | ASSERT(Buffer != NULL);\r | |
162 | \r | |
163 | QuickSortWorker(\r | |
164 | BufferToSort,\r | |
165 | Count,\r | |
166 | ElementSize,\r | |
167 | CompareFunction,\r | |
168 | Buffer);\r | |
169 | \r | |
170 | FreePool(Buffer);\r | |
171 | return;\r | |
172 | }\r | |
125c2cf4 | 173 | \r |
174 | /**\r | |
175 | Not supported in Base version.\r | |
176 | \r | |
177 | ASSERT and return 0.\r | |
178 | **/\r | |
179 | INTN\r | |
180 | DevicePathCompare (\r | |
181 | IN VOID *Buffer1,\r | |
182 | IN VOID *Buffer2\r | |
183 | )\r | |
184 | {\r | |
185 | ASSERT(FALSE);\r | |
186 | return 0;\r | |
187 | } |