1 /** @file
2 Library used for sorting routines.
3
4 Copyright (c) 2009 - 2014, Intel Corporation. All rights reserved. <BR>
5 This program and the accompanying materials
6 are licensed and made available under the terms and conditions of the BSD License
7 which accompanies this distribution. The full text of the license may be found at
8 http://opensource.org/licenses/bsd-license.php
9
10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
12
13 **/
14 #include <Uefi.h>
15
16 #include <Library/BaseLib.h>
17 #include <Library/BaseMemoryLib.h>
18 #include <Library/DebugLib.h>
19 #include <Library/MemoryAllocationLib.h>
20 #include <Library/SortLib.h>
21
22 /**
23 Worker function for QuickSorting. This function is identical to PerformQuickSort,
24 except that is uses the pre-allocated buffer so the in place sorting does not need to
25 allocate and free buffers constantly.
26
27 Each element must be equal sized.
28
29 if BufferToSort is NULL, then ASSERT.
30 if CompareFunction is NULL, then ASSERT.
31 if Buffer is NULL, then ASSERT.
32
33 if Count is < 2 then perform no action.
34 if Size is < 1 then perform no action.
35
36 @param[in, out] BufferToSort on call a Buffer of (possibly sorted) elements
37 on return a buffer of sorted elements
38 @param[in] Count the number of elements in the buffer to sort
39 @param[in] ElementSize Size of an element in bytes
40 @param[in] CompareFunction The function to call to perform the comparison
41 of any 2 elements
42 @param[in] Buffer Buffer of size ElementSize for use in swapping
43 **/
44 VOID
45 EFIAPI
QuickSortWorker(IN OUT VOID * BufferToSort,IN CONST UINTN Count,IN CONST UINTN ElementSize,IN SORT_COMPARE CompareFunction,IN VOID * Buffer)46 QuickSortWorker (
47 IN OUT VOID *BufferToSort,
48 IN CONST UINTN Count,
49 IN CONST UINTN ElementSize,
50 IN SORT_COMPARE CompareFunction,
51 IN VOID *Buffer
52 )
53 {
54 VOID *Pivot;
55 UINTN LoopCount;
56 UINTN NextSwapLocation;
57
58 ASSERT(BufferToSort != NULL);
59 ASSERT(CompareFunction != NULL);
60 ASSERT(Buffer != NULL);
61
62 if ( Count < 2
63 || ElementSize < 1
64 ){
65 return;
66 }
67
68 NextSwapLocation = 0;
69
70 //
71 // pick a pivot (we choose last element)
72 //
73 Pivot = ((UINT8*)BufferToSort+((Count-1)*ElementSize));
74
75 //
76 // Now get the pivot such that all on "left" are below it
77 // and everything "right" are above it
78 //
79 for ( LoopCount = 0
80 ; LoopCount < Count -1
81 ; LoopCount++
82 ){
83 //
84 // if the element is less than the pivot
85 //
86 if (CompareFunction((VOID*)((UINT8*)BufferToSort+((LoopCount)*ElementSize)),Pivot) <= 0){
87 //
88 // swap
89 //
90 CopyMem (Buffer, (UINT8*)BufferToSort+(NextSwapLocation*ElementSize), ElementSize);
91 CopyMem ((UINT8*)BufferToSort+(NextSwapLocation*ElementSize), (UINT8*)BufferToSort+((LoopCount)*ElementSize), ElementSize);
92 CopyMem ((UINT8*)BufferToSort+((LoopCount)*ElementSize), Buffer, ElementSize);
93
94 //
95 // increment NextSwapLocation
96 //
97 NextSwapLocation++;
98 }
99 }
100 //
101 // swap pivot to it's final position (NextSwapLocaiton)
102 //
103 CopyMem (Buffer, Pivot, ElementSize);
104 CopyMem (Pivot, (UINT8*)BufferToSort+(NextSwapLocation*ElementSize), ElementSize);
105 CopyMem ((UINT8*)BufferToSort+(NextSwapLocation*ElementSize), Buffer, ElementSize);
106
107 //
108 // Now recurse on 2 paritial lists. neither of these will have the 'pivot' element
109 // IE list is sorted left half, pivot element, sorted right half...
110 //
111 if (NextSwapLocation >= 2) {
112 QuickSortWorker(
113 BufferToSort,
114 NextSwapLocation,
115 ElementSize,
116 CompareFunction,
117 Buffer);
118 }
119
120 if ((Count - NextSwapLocation - 1) >= 2) {
121 QuickSortWorker(
122 (UINT8 *)BufferToSort + (NextSwapLocation+1) * ElementSize,
123 Count - NextSwapLocation - 1,
124 ElementSize,
125 CompareFunction,
126 Buffer);
127 }
128 return;
129 }
130 /**
131 Function to perform a Quick Sort alogrithm on a buffer of comparable elements.
132
133 Each element must be equal sized.
134
135 if BufferToSort is NULL, then ASSERT.
136 if CompareFunction is NULL, then ASSERT.
137
138 if Count is < 2 then perform no action.
139 if Size is < 1 then perform no action.
140
141 @param[in, out] BufferToSort on call a Buffer of (possibly sorted) elements
142 on return a buffer of sorted elements
143 @param[in] Count the number of elements in the buffer to sort
144 @param[in] ElementSize Size of an element in bytes
145 @param[in] CompareFunction The function to call to perform the comparison
146 of any 2 elements
147 **/
148 VOID
149 EFIAPI
PerformQuickSort(IN OUT VOID * BufferToSort,IN CONST UINTN Count,IN CONST UINTN ElementSize,IN SORT_COMPARE CompareFunction)150 PerformQuickSort (
151 IN OUT VOID *BufferToSort,
152 IN CONST UINTN Count,
153 IN CONST UINTN ElementSize,
154 IN SORT_COMPARE CompareFunction
155 )
156 {
157 VOID *Buffer;
158
159 ASSERT(BufferToSort != NULL);
160 ASSERT(CompareFunction != NULL);
161
162 Buffer = AllocateZeroPool(ElementSize);
163 ASSERT(Buffer != NULL);
164
165 QuickSortWorker(
166 BufferToSort,
167 Count,
168 ElementSize,
169 CompareFunction,
170 Buffer);
171
172 FreePool(Buffer);
173 return;
174 }
175
176 /**
177 Not supported in Base version.
178
179 @param[in] Buffer1 Ignored.
180 @param[in] Buffer2 Ignored.
181
182 ASSERT and return 0.
183 **/
184 INTN
185 EFIAPI
DevicePathCompare(IN CONST VOID * Buffer1,IN CONST VOID * Buffer2)186 DevicePathCompare (
187 IN CONST VOID *Buffer1,
188 IN CONST VOID *Buffer2
189 )
190 {
191 ASSERT(FALSE);
192 return 0;
193 }
194
195 /**
196 Function to compare 2 strings without regard to case of the characters.
197
198 @param[in] Buffer1 Pointer to String to compare.
199 @param[in] Buffer2 Pointer to second String to compare.
200
201 @retval 0 Buffer1 equal to Buffer2.
202 @return < 0 Buffer1 is less than Buffer2.
203 @return > 0 Buffer1 is greater than Buffer2.
204 **/
205 INTN
206 EFIAPI
StringNoCaseCompare(IN CONST VOID * Buffer1,IN CONST VOID * Buffer2)207 StringNoCaseCompare (
208 IN CONST VOID *Buffer1,
209 IN CONST VOID *Buffer2
210 )
211 {
212 ASSERT(FALSE);
213 return 0;
214 }
215
216
217 /**
218 Function to compare 2 strings.
219
220 @param[in] Buffer1 Pointer to String to compare (CHAR16**).
221 @param[in] Buffer2 Pointer to second String to compare (CHAR16**).
222
223 @retval 0 Buffer1 equal to Buffer2.
224 @return < 0 Buffer1 is less than Buffer2.
225 @return > 0 Buffer1 is greater than Buffer2.
226 **/
227 INTN
228 EFIAPI
StringCompare(IN CONST VOID * Buffer1,IN CONST VOID * Buffer2)229 StringCompare (
230 IN CONST VOID *Buffer1,
231 IN CONST VOID *Buffer2
232 )
233 {
234 ASSERT(FALSE);
235 return 0;
236 }
237
238
239