Step to UEFI (60） —– GUID和UUID

了解了一下 UUID 和 GUID , 资料上来看，这两个是同一个东西。GUID 是 MS 定义的 UUID 的一种实现方法. 两者在写法上稍微有些差别【参考1】【参考2】：

GUID:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx (8-4-4-4-12)

UUID:xxxxxxxx-xxxx-xxxx-xxxxxxxxxxxxxxxx (8-4-4-16)

在 UEFI 中，我们经常看到类似下面的定义

“cf8e16a5-c1e8-4e25-b712-4f54a96702c8”

#define EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID \
{ \
0x964e5b22, 0x6459, 0x11d2, {0x8e, 0x39, 0x0, 0xa0, 0xc9, 0x69, 0x72, 0x3b } \
}

UUID PadFileGuid;

对于 GUID ,可以在 \MdePkg\Include\Base.h 看到下面的定义

///
/// 128 bit buffer containing a unique identifier value.
/// Unless otherwise specified, aligned on a 64 bit boundary.
///
typedef struct {
  UINT32  Data1;
  UINT16  Data2;
  UINT16  Data3;
  UINT8   Data4[8];
} GUID;

 

同时，在 \MdePkg\Include\Uefi\UefiBaseType.h 有下面的定义

///
/// 128-bit buffer containing a unique identifier value.
///
typedef GUID                      EFI_GUID;

 

在 \BaseTools\Source\C\Common\CommonLib.c 有一个打印输出的例子可以直接拿出来用

EFI_STATUS
PrintGuid (
  IN EFI_GUID *Guid
  )
/*++

Routine Description:

  This function prints a GUID to STDOUT.

Arguments:

  Guid    Pointer to a GUID to print.

Returns:

  EFI_SUCCESS             The GUID was printed.
  EFI_INVALID_PARAMETER   The input was NULL.

--*/
{
  if (Guid == NULL) {
    Error (NULL, 0, 2000, "Invalid parameter", "PrintGuidToBuffer() called with a NULL value");
    return EFI_INVALID_PARAMETER;
  }

  printf (
    "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x\n",
    (unsigned) Guid->Data1,
    Guid->Data2,
    Guid->Data3,
    Guid->Data4[0],
    Guid->Data4[1],
    Guid->Data4[2],
    Guid->Data4[3],
    Guid->Data4[4],
    Guid->Data4[5],
    Guid->Data4[6],
    Guid->Data4[7]
    );
  return EFI_SUCCESS;
}

 

最后，写一个输出的例子

#include  <Uefi.h>
#include  <Library/UefiLib.h>
#include  <Library/ShellCEntryLib.h>

#include  <stdio.h>
#include  <stdlib.h>
#include  <wchar.h>

#include <Protocol/EfiShell.h>
#include <Library/ShellLib.h>


extern EFI_BOOT_SERVICES         *gBS;
extern EFI_SYSTEM_TABLE			 *gST;
extern EFI_RUNTIME_SERVICES 	 *gRT;

#define GUID1 \
  { \
    0x964e5b22, 0x6459, 0x11d2, {0x8e, 0x39, 0x0, 0xa0, 0xc9, 0x69, 0x72, 0x3b } \
  }

#define GUID2 \
  { \
    0x33221100, 0x5544, 0x7766, {0x88, 0x99, 0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF } \
  }
  
EFI_STATUS
PrintGuid (
  IN EFI_GUID *Guid
  )
  
/*++

Routine Description:

  This function prints a GUID to STDOUT.

Arguments:

  Guid    Pointer to a GUID to print.

Returns:

  EFI_SUCCESS             The GUID was printed.
  EFI_INVALID_PARAMETER   The input was NULL.

--*/
{
  if (Guid == NULL) {
	printf("Parameter error!\n");
    return EFI_INVALID_PARAMETER;
  }

  printf (
    "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x\n",
    (unsigned) Guid->Data1,
    Guid->Data2,
    Guid->Data3,
    Guid->Data4[0],
    Guid->Data4[1],
    Guid->Data4[2],
    Guid->Data4[3],
    Guid->Data4[4],
    Guid->Data4[5],
    Guid->Data4[6],
    Guid->Data4[7]
    );
  return EFI_SUCCESS;
}

int
EFIAPI
main (
  IN int Argc,
  IN CHAR16 **Argv
  )
{
  EFI_GUID T1=GUID1;
  EFI_GUID T2=GUID2;
  
  PrintGuid(&T1);
  PrintGuid(&T2);
  
  return EFI_SUCCESS;
}

 

运行结果

完整代码下载

GUIDTest

参考：
1.http://baike.baidu.com/view/1052579.htm UUID
2.http://blog.csdn.net/forlong401/article/details/7580147 UUID 和 GUID 的区别
3.https://en.wikipedia.org/wiki/Globally_unique_identifier Globally unique identifier
4.https://en.wikipedia.org/wiki/Universally_unique_identifier Universally unique identifier