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 - 2016, 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 A pointer to the destination GUID. 38 @param SourceGuid A pointer to the source GUID. 39 40 @return DestinationGuid. 41 42 **/ 43 GUID * 44 EFIAPI 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 79 CompareGuid ( 80 IN CONST GUID *Guid1, 81 IN CONST GUID *Guid2 82 ) 83 { 84 UINT64 LowPartOfGuid1; 85 UINT64 LowPartOfGuid2; 86 UINT64 HighPartOfGuid1; 87 UINT64 HighPartOfGuid2; 88 89 LowPartOfGuid1 = ReadUnaligned64 ((CONST UINT64*) Guid1); 90 LowPartOfGuid2 = ReadUnaligned64 ((CONST UINT64*) Guid2); 91 HighPartOfGuid1 = ReadUnaligned64 ((CONST UINT64*) Guid1 + 1); 92 HighPartOfGuid2 = ReadUnaligned64 ((CONST UINT64*) Guid2 + 1); 93 94 return (BOOLEAN) (LowPartOfGuid1 == LowPartOfGuid2 && HighPartOfGuid1 == HighPartOfGuid2); 95 } 96 97 /** 98 Scans a target buffer for a GUID, and returns a pointer to the matching GUID 99 in the target buffer. 100 101 This function searches the target buffer specified by Buffer and Length from 102 the lowest address to the highest address at 128-bit increments for the 128-bit 103 GUID value that matches Guid. If a match is found, then a pointer to the matching 104 GUID in the target buffer is returned. If no match is found, then NULL is returned. 105 If Length is 0, then NULL is returned. 106 107 If Length > 0 and Buffer is NULL, then ASSERT(). 108 If Buffer is not aligned on a 32-bit boundary, then ASSERT(). 109 If Length is not aligned on a 128-bit boundary, then ASSERT(). 110 If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT(). 111 112 @param Buffer The pointer to the target buffer to scan. 113 @param Length The number of bytes in Buffer to scan. 114 @param Guid The value to search for in the target buffer. 115 116 @return A pointer to the matching Guid in the target buffer or NULL otherwise. 117 118 **/ 119 VOID * 120 EFIAPI 121 ScanGuid ( 122 IN CONST VOID *Buffer, 123 IN UINTN Length, 124 IN CONST GUID *Guid 125 ) 126 { 127 CONST GUID *GuidPtr; 128 129 ASSERT (((UINTN)Buffer & (sizeof (Guid->Data1) - 1)) == 0); 130 ASSERT (Length <= (MAX_ADDRESS - (UINTN)Buffer + 1)); 131 ASSERT ((Length & (sizeof (*GuidPtr) - 1)) == 0); 132 133 GuidPtr = (GUID*)Buffer; 134 Buffer = GuidPtr + Length / sizeof (*GuidPtr); 135 while (GuidPtr < (CONST GUID*)Buffer) { 136 if (CompareGuid (GuidPtr, Guid)) { 137 return (VOID*)GuidPtr; 138 } 139 GuidPtr++; 140 } 141 return NULL; 142 } 143 144 /** 145 Checks if the given GUID is a zero GUID. 146 147 This function checks whether the given GUID is a zero GUID. If the GUID is 148 identical to a zero GUID then TRUE is returned. Otherwise, FALSE is returned. 149 150 If Guid is NULL, then ASSERT(). 151 152 @param Guid The pointer to a 128 bit GUID. 153 154 @retval TRUE Guid is a zero GUID. 155 @retval FALSE Guid is not a zero GUID. 156 157 **/ 158 BOOLEAN 159 EFIAPI 160 IsZeroGuid ( 161 IN CONST GUID *Guid 162 ) 163 { 164 UINT64 LowPartOfGuid; 165 UINT64 HighPartOfGuid; 166 167 LowPartOfGuid = ReadUnaligned64 ((CONST UINT64*) Guid); 168 HighPartOfGuid = ReadUnaligned64 ((CONST UINT64*) Guid + 1); 169 170 return (BOOLEAN) (LowPartOfGuid == 0 && HighPartOfGuid == 0); 171 } 172
