1 /** @file
2 ScanMem8() and ScanMemN() implementation.
3
4 The following BaseMemoryLib instances contain the same copy of this file:
5
6 BaseMemoryLib
7 BaseMemoryLibMmx
8 BaseMemoryLibSse2
9 BaseMemoryLibRepStr
10 BaseMemoryLibOptDxe
11 BaseMemoryLibOptPei
12 PeiMemoryLib
13 UefiMemoryLib
14
15 Copyright (c) 2006 - 2009, Intel Corporation. All rights reserved.<BR>
16 This program and the accompanying materials
17 are licensed and made available under the terms and conditions of the BSD License
18 which accompanies this distribution. The full text of the license may be found at
19 http://opensource.org/licenses/bsd-license.php.
20
21 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
22 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
23
24 **/
25
26 #include "MemLibInternals.h"
27
28 /**
29 Scans a target buffer for an 8-bit value, and returns a pointer to the matching 8-bit value
30 in the target buffer.
31
32 This function searches the target buffer specified by Buffer and Length from the lowest
33 address to the highest address for an 8-bit value that matches Value. If a match is found,
34 then a pointer to the matching byte in the target buffer is returned. If no match is found,
35 then NULL is returned. If Length is 0, then NULL is returned.
36
37 If Length > 0 and Buffer is NULL, then ASSERT().
38 If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
39
40 @param Buffer The pointer to the target buffer to scan.
41 @param Length The number of bytes in Buffer to scan.
42 @param Value The value to search for in the target buffer.
43
44 @return A pointer to the matching byte in the target buffer or NULL otherwise.
45
46 **/
47 VOID *
48 EFIAPI
ScanMem8(IN CONST VOID * Buffer,IN UINTN Length,IN UINT8 Value)49 ScanMem8 (
50 IN CONST VOID *Buffer,
51 IN UINTN Length,
52 IN UINT8 Value
53 )
54 {
55 if (Length == 0) {
56 return NULL;
57 }
58 ASSERT (Buffer != NULL);
59 ASSERT ((Length - 1) <= (MAX_ADDRESS - (UINTN)Buffer));
60
61 return (VOID*)InternalMemScanMem8 (Buffer, Length, Value);
62 }
63
64 /**
65 Scans a target buffer for a UINTN sized value, and returns a pointer to the matching
66 UINTN sized value in the target buffer.
67
68 This function searches the target buffer specified by Buffer and Length from the lowest
69 address to the highest address for a UINTN sized value that matches Value. If a match is found,
70 then a pointer to the matching byte in the target buffer is returned. If no match is found,
71 then NULL is returned. If Length is 0, then NULL is returned.
72
73 If Length > 0 and Buffer is NULL, then ASSERT().
74 If Buffer is not aligned on a UINTN boundary, then ASSERT().
75 If Length is not aligned on a UINTN boundary, then ASSERT().
76 If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
77
78 @param Buffer The pointer to the target buffer to scan.
79 @param Length The number of bytes in Buffer to scan.
80 @param Value The value to search for in the target buffer.
81
82 @return A pointer to the matching byte in the target buffer or NULL otherwise.
83
84 **/
85 VOID *
86 EFIAPI
ScanMemN(IN CONST VOID * Buffer,IN UINTN Length,IN UINTN Value)87 ScanMemN (
88 IN CONST VOID *Buffer,
89 IN UINTN Length,
90 IN UINTN Value
91 )
92 {
93 if (sizeof (UINTN) == sizeof (UINT64)) {
94 return ScanMem64 (Buffer, Length, (UINT64)Value);
95 } else {
96 return ScanMem32 (Buffer, Length, (UINT32)Value);
97 }
98 }
99
100