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2 Utility functions to generate checksum based on 2's complement
5 Copyright (c) 2007, Intel Corporation<BR>
6 All rights reserved. This program and the accompanying materials
7 are licensed and made available under the terms and conditions of the BSD License
8 which accompanies this distribution. The full text of the license may be found at
9 http://opensource.org/licenses/bsd-license.php
11 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
12 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
17 // Include common header file for this module.
19 #include <BaseLibInternals.h>
23 Calculate the sum of all elements in a buffer in unit of UINT8.
24 During calculation, the carry bits are dropped.
26 This function calculates the sum of all elements in a buffer
27 in unit of UINT8. The carry bits in result of addition are dropped.
28 The result is returned as UINT8. If Length is Zero, then Zero is
31 If Buffer is NULL, then ASSERT().
32 If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
34 @param Buffer Pointer to the buffer to carry out the sum operation.
35 @param Length The size, in bytes, of Buffer .
37 @return Sum The sum of Buffer with carry bits dropped during additions.
43 IN CONST UINT8
*Buffer
,
50 ASSERT (Buffer
!= NULL
);
51 ASSERT (Length
<= (MAX_ADDRESS
- ((UINTN
) Buffer
) + 1));
53 for (Sum
= 0, Count
= 0; Count
< Length
; Count
++) {
54 Sum
= (UINT8
) (Sum
+ *(Buffer
+ Count
));
62 Returns the two's complement checksum of all elements in a buffer
65 This function first calculates the sum of the 8-bit values in the
66 buffer specified by Buffer and Length. The carry bits in the result
67 of addition are dropped. Then, the two's complement of the sum is
68 returned. If Length is 0, then 0 is returned.
70 If Buffer is NULL, then ASSERT().
71 If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
74 @param Buffer Pointer to the buffer to carry out the checksum operation.
75 @param Length The size, in bytes, of Buffer.
77 @return Checksum The 2's complement checksum of Buffer.
83 IN CONST UINT8
*Buffer
,
89 CheckSum
= CalculateSum8 (Buffer
, Length
);
92 // Return the checksum based on 2's complement.
94 return (UINT8
) (0x100 - CheckSum
);
98 Returns the sum of all elements in a buffer of 16-bit values. During
99 calculation, the carry bits are dropped.
101 This function calculates the sum of the 16-bit values in the buffer
102 specified by Buffer and Length. The carry bits in result of addition are dropped.
103 The 16-bit result is returned. If Length is 0, then 0 is returned.
105 If Buffer is NULL, then ASSERT().
106 If Buffer is not aligned on a 16-bit boundary, then ASSERT().
107 If Length is not aligned on a 16-bit boundary, then ASSERT().
108 If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
110 @param Buffer Pointer to the buffer to carry out the sum operation.
111 @param Length The size, in bytes, of Buffer.
113 @return Sum The sum of Buffer with carry bits dropped during additions.
119 IN CONST UINT16
*Buffer
,
126 ASSERT (Buffer
!= NULL
);
127 ASSERT (((UINTN
) Buffer
& 0x1) == 0);
128 ASSERT ((Length
& 0x1) == 0);
129 ASSERT (Length
<= (MAX_ADDRESS
- ((UINTN
) Buffer
) + 1));
132 for (Sum
= 0, Count
= 0; Count
< Length
; Count
++) {
133 Sum
= (UINT16
) (Sum
+ *(Buffer
+ Count
));
141 Returns the two's complement checksum of all elements in a buffer of
144 This function first calculates the sum of the 16-bit values in the buffer
145 specified by Buffer and Length. The carry bits in the result of addition
146 are dropped. Then, the two's complement of the sum is returned. If Length
147 is 0, then 0 is returned.
149 If Buffer is NULL, then ASSERT().
150 If Buffer is not aligned on a 16-bit boundary, then ASSERT().
151 If Length is not aligned on a 16-bit boundary, then ASSERT().
152 If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
154 @param Buffer Pointer to the buffer to carry out the checksum operation.
155 @param Length The size, in bytes, of Buffer.
157 @return Checksum The 2's complement checksum of Buffer.
162 CalculateCheckSum16 (
163 IN CONST UINT16
*Buffer
,
169 CheckSum
= CalculateSum16 (Buffer
, Length
);
172 // Return the checksum based on 2's complement.
174 return (UINT16
) (0x10000 - CheckSum
);
179 Returns the sum of all elements in a buffer of 32-bit values. During
180 calculation, the carry bits are dropped.
182 This function calculates the sum of the 32-bit values in the buffer
183 specified by Buffer and Length. The carry bits in result of addition are dropped.
184 The 32-bit result is returned. If Length is 0, then 0 is returned.
186 If Buffer is NULL, then ASSERT().
187 If Buffer is not aligned on a 32-bit boundary, then ASSERT().
188 If Length is not aligned on a 32-bit boundary, then ASSERT().
189 If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
191 @param Buffer Pointer to the buffer to carry out the sum operation.
192 @param Length The size, in bytes, of Buffer.
194 @return Sum The sum of Buffer with carry bits dropped during additions.
200 IN CONST UINT32
*Buffer
,
207 ASSERT (Buffer
!= NULL
);
208 ASSERT (((UINTN
) Buffer
& 0x3) == 0);
209 ASSERT ((Length
& 0x3) == 0);
210 ASSERT (Length
<= (MAX_ADDRESS
- ((UINTN
) Buffer
) + 1));
213 for (Sum
= 0, Count
= 0; Count
< Length
; Count
++) {
214 Sum
= Sum
+ *(Buffer
+ Count
);
222 Returns the two's complement checksum of all elements in a buffer of
225 This function first calculates the sum of the 32-bit values in the buffer
226 specified by Buffer and Length. The carry bits in the result of addition
227 are dropped. Then, the two's complement of the sum is returned. If Length
228 is 0, then 0 is returned.
230 If Buffer is NULL, then ASSERT().
231 If Buffer is not aligned on a 32-bit boundary, then ASSERT().
232 If Length is not aligned on a 32-bit boundary, then ASSERT().
233 If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
235 @param Buffer Pointer to the buffer to carry out the checksum operation.
236 @param Length The size, in bytes, of Buffer.
238 @return Checksum The 2's complement checksum of Buffer.
243 CalculateCheckSum32 (
244 IN CONST UINT32
*Buffer
,
250 CheckSum
= CalculateSum32 (Buffer
, Length
);
253 // Return the checksum based on 2's complement.
255 return (UINT32
) ((UINT32
)(-1) - CheckSum
+ 1);
260 Returns the sum of all elements in a buffer of 64-bit values. During
261 calculation, the carry bits are dropped.
263 This function calculates the sum of the 64-bit values in the buffer
264 specified by Buffer and Length. The carry bits in result of addition are dropped.
265 The 64-bit result is returned. If Length is 0, then 0 is returned.
267 If Buffer is NULL, then ASSERT().
268 If Buffer is not aligned on a 64-bit boundary, then ASSERT().
269 If Length is not aligned on a 64-bit boundary, then ASSERT().
270 If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
272 @param Buffer Pointer to the buffer to carry out the sum operation.
273 @param Length The size, in bytes, of Buffer.
275 @return Sum The sum of Buffer with carry bits dropped during additions.
281 IN CONST UINT64
*Buffer
,
288 ASSERT (Buffer
!= NULL
);
289 ASSERT (((UINTN
) Buffer
& 0x7) == 0);
290 ASSERT ((Length
& 0x7) == 0);
291 ASSERT (Length
<= (MAX_ADDRESS
- ((UINTN
) Buffer
) + 1));
293 for (Sum
= 0, Count
= 0; Count
< Length
; Count
++) {
294 Sum
= Sum
+ *(Buffer
+ Count
);
302 Returns the two's complement checksum of all elements in a buffer of
305 This function first calculates the sum of the 64-bit values in the buffer
306 specified by Buffer and Length. The carry bits in the result of addition
307 are dropped. Then, the two's complement of the sum is returned. If Length
308 is 0, then 0 is returned.
310 If Buffer is NULL, then ASSERT().
311 If Buffer is not aligned on a 64-bit boundary, then ASSERT().
312 If Length is not aligned on a 64-bit boundary, then ASSERT().
313 If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
315 @param Buffer Pointer to the buffer to carry out the checksum operation.
316 @param Length The size, in bytes, of Buffer.
318 @return Checksum The 2's complement checksum of Buffer.
323 CalculateCheckSum64 (
324 IN CONST UINT64
*Buffer
,
330 CheckSum
= CalculateSum64 (Buffer
, Length
);
333 // Return the checksum based on 2's complement.
335 return (UINT64
) ((UINT64
)(-1) - CheckSum
+ 1);