1 /** @file
2 Implementation of GUID functions.
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 Copies a source GUID to a destination GUID.
30
31 This function copies the contents of the 128-bit GUID specified by SourceGuid to
32 DestinationGuid, and returns DestinationGuid.
33
34 If DestinationGuid is NULL, then ASSERT().
35 If SourceGuid is NULL, then ASSERT().
36
37 @param DestinationGuid Pointer to the destination GUID.
38 @param SourceGuid Pointer to the source GUID.
39
40 @return DestinationGuid.
41
42 **/
43 GUID *
44 EFIAPI
CopyGuid(OUT GUID * DestinationGuid,IN CONST GUID * SourceGuid)45 CopyGuid (
46 OUT GUID *DestinationGuid,
47 IN CONST GUID *SourceGuid
48 )
49 {
50 WriteUnaligned64 (
51 (UINT64*)DestinationGuid,
52 ReadUnaligned64 ((CONST UINT64*)SourceGuid)
53 );
54 WriteUnaligned64 (
55 (UINT64*)DestinationGuid + 1,
56 ReadUnaligned64 ((CONST UINT64*)SourceGuid + 1)
57 );
58 return DestinationGuid;
59 }
60
61 /**
62 Compares two GUIDs.
63
64 This function compares Guid1 to Guid2. If the GUIDs are identical then TRUE is returned.
65 If there are any bit differences in the two GUIDs, then FALSE is returned.
66
67 If Guid1 is NULL, then ASSERT().
68 If Guid2 is NULL, then ASSERT().
69
70 @param Guid1 A pointer to a 128 bit GUID.
71 @param Guid2 A pointer to a 128 bit GUID.
72
73 @retval TRUE Guid1 and Guid2 are identical.
74 @retval FALSE Guid1 and Guid2 are not identical.
75
76 **/
77 BOOLEAN
78 EFIAPI
CompareGuid(IN CONST GUID * Guid1,IN CONST GUID * Guid2)79 CompareGuid (
80 IN CONST GUID *Guid1,
81 IN CONST GUID *Guid2
82 )
83 {
84 return (CompareMem(Guid1, Guid2, sizeof(GUID) == 0)) ? TRUE : FALSE;
85 }
86
87 /**
88 Scans a target buffer for a GUID, and returns a pointer to the matching GUID
89 in the target buffer.
90
91 This function searches the target buffer specified by Buffer and Length from
92 the lowest address to the highest address at 128-bit increments for the 128-bit
93 GUID value that matches Guid. If a match is found, then a pointer to the matching
94 GUID in the target buffer is returned. If no match is found, then NULL is returned.
95 If Length is 0, then NULL is returned.
96
97 If Length > 0 and Buffer is NULL, then ASSERT().
98 If Buffer is not aligned on a 32-bit boundary, then ASSERT().
99 If Length is not aligned on a 128-bit boundary, then ASSERT().
100 If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
101
102 @param Buffer Pointer to the target buffer to scan.
103 @param Length Number of bytes in Buffer to scan.
104 @param Guid Value to search for in the target buffer.
105
106 @return A pointer to the matching Guid in the target buffer or NULL otherwise.
107
108 **/
109 VOID *
110 EFIAPI
ScanGuid(IN CONST VOID * Buffer,IN UINTN Length,IN CONST GUID * Guid)111 ScanGuid (
112 IN CONST VOID *Buffer,
113 IN UINTN Length,
114 IN CONST GUID *Guid
115 )
116 {
117 CONST GUID *GuidPtr;
118
119 ASSERT (((UINTN)Buffer & (sizeof (Guid->Data1) - 1)) == 0);
120 ASSERT (Length <= (MAX_ADDRESS - (UINTN)Buffer + 1));
121 ASSERT ((Length & (sizeof (*GuidPtr) - 1)) == 0);
122
123 GuidPtr = (GUID*)Buffer;
124 Buffer = GuidPtr + Length / sizeof (*GuidPtr);
125 while (GuidPtr < (CONST GUID*)Buffer) {
126 if (CompareGuid (GuidPtr, Guid)) {
127 return (VOID*)GuidPtr;
128 }
129 GuidPtr++;
130 }
131 return NULL;
132 }
133