1 /*++
2
3 Copyright (c) 2004 - 2006, Intel Corporation. All rights reserved.<BR>
4 This program and the accompanying materials
5 are licensed and made available under the terms and conditions of the BSD License
6 which accompanies this distribution. The full text of the license may be found at
7 http://opensource.org/licenses/bsd-license.php
8
9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
11
12 Module Name:
13
14 MemLibGuid.c
15
16 Abstract:
17
18 Implementation of GUID functions.
19
20 --*/
21
22 #include "BaseMemoryLibInternal.h"
23
24 /**
25 Copies a source GUID to a destination GUID.
26
27 This function copies the contents of the 128-bit GUID specified by SourceGuid to
28 DestinationGuid, and returns DestinationGuid.
29 If DestinationGuid is NULL, then ASSERT().
30 If SourceGuid is NULL, then ASSERT().
31
32 @param DestinationGuid Pointer to the destination GUID.
33 @param SourceGuid Pointer to the source GUID.
34
35 @return DestinationGuid.
36
37 **/
38 GUID *
39 EFIAPI
CopyGuid(OUT GUID * DestinationGuid,IN CONST GUID * SourceGuid)40 CopyGuid (
41 OUT GUID *DestinationGuid,
42 IN CONST GUID *SourceGuid
43 )
44 {
45 WriteUnaligned64 (
46 (UINT64*)DestinationGuid,
47 ReadUnaligned64 ((CONST UINT64*)SourceGuid)
48 );
49 WriteUnaligned64 (
50 (UINT64*)DestinationGuid + 1,
51 ReadUnaligned64 ((CONST UINT64*)SourceGuid + 1)
52 );
53 return DestinationGuid;
54 }
55
56 /**
57 Compares two GUIDs.
58
59 This function compares Guid1 to Guid2. If the GUIDs are identical then TRUE is returned.
60 If there are any bit differences in the two GUIDs, then FALSE is returned.
61 If Guid1 is NULL, then ASSERT().
62 If Guid2 is NULL, then ASSERT().
63
64 @param Guid1 A pointer to a 128 bit GUID.
65 @param Guid2 A pointer to a 128 bit GUID.
66
67 @retval TRUE Guid1 and Guid2 are identical.
68 @retval FALSE Guid1 and Guid2 are not identical.
69
70 **/
71 BOOLEAN
72 EFIAPI
GlueCompareGuid(IN CONST GUID * Guid1,IN CONST GUID * Guid2)73 GlueCompareGuid (
74 IN CONST GUID *Guid1,
75 IN CONST GUID *Guid2
76 )
77 {
78 UINT64 LowPartOfGuid1;
79 UINT64 LowPartOfGuid2;
80 UINT64 HighPartOfGuid1;
81 UINT64 HighPartOfGuid2;
82
83 LowPartOfGuid1 = ReadUnaligned64 ((CONST UINT64*) Guid1);
84 LowPartOfGuid2 = ReadUnaligned64 ((CONST UINT64*) Guid2);
85 HighPartOfGuid1 = ReadUnaligned64 ((CONST UINT64*) Guid1 + 1);
86 HighPartOfGuid2 = ReadUnaligned64 ((CONST UINT64*) Guid2 + 1);
87
88 return (BOOLEAN) (LowPartOfGuid1 == LowPartOfGuid2 && HighPartOfGuid1 == HighPartOfGuid2);
89 }
90
91 /**
92 Scans a target buffer for a GUID, and returns a pointer to the matching GUID
93 in the target buffer.
94
95 This function searches target the buffer specified by Buffer and Length from
96 the lowest address to the highest address at 128-bit increments for the 128-bit
97 GUID value that matches Guid. If a match is found, then a pointer to the matching
98 GUID in the target buffer is returned. If no match is found, then NULL is returned.
99 If Length is 0, then NULL is returned.
100 If Length > 0 and Buffer is NULL, then ASSERT().
101 If Buffer is not aligned on a 32-bit boundary, then ASSERT().
102 If Length is not aligned on a 128-bit boundary, then ASSERT().
103 If Length is greater than (MAX_ADDRESS ? Buffer + 1), then ASSERT().
104
105 @param Buffer Pointer to the target buffer to scan.
106 @param Length Number of bytes in Buffer to scan.
107 @param Guid Value to search for in the target buffer.
108
109 @return A pointer to the matching Guid in the target buffer or NULL otherwise.
110
111 **/
112 VOID *
113 EFIAPI
ScanGuid(IN CONST VOID * Buffer,IN UINTN Length,IN CONST GUID * Guid)114 ScanGuid (
115 IN CONST VOID *Buffer,
116 IN UINTN Length,
117 IN CONST GUID *Guid
118 )
119 {
120 CONST GUID *GuidPtr;
121
122 ASSERT (((UINTN)Buffer & (sizeof (Guid->Data1) - 1)) == 0);
123 ASSERT (Length <= (MAX_ADDRESS - (UINTN)Buffer + 1));
124 ASSERT ((Length & (sizeof (*GuidPtr) - 1)) == 0);
125
126 GuidPtr = (GUID*)Buffer;
127 Buffer = GuidPtr + Length / sizeof (*GuidPtr);
128 while (GuidPtr < (CONST GUID*)Buffer) {
129 if (CompareGuid (GuidPtr, Guid)) {
130 return (VOID*)GuidPtr;
131 }
132 GuidPtr++;
133 }
134 return NULL;
135 }
136