valuetostring.c

来自「EFI BIOS是Intel提出的下一代的BIOS标准。这里上传的Edk源代码是」· C语言 代码 · 共 224 行

/*++

Copyright (c) 2004, Intel Corporation                                                         
All rights reserved. This program and the accompanying materials                          
are licensed and made available under the terms and conditions of the BSD License         
which accompanies this distribution.  The full text of the license may be found at        
http://opensource.org/licenses/bsd-license.php                                            
                                                                                          
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             

Module Name:

  ValueToString.c

Abstract:

  Routines changing value to Hex or Dec string

--*/

#include "Tiano.h"
#include "EfiDriverLib.h"

static CHAR16 mHexStr[] = { L'0', L'1', L'2', L'3', L'4', L'5', L'6', L'7',
                            L'8', L'9', L'A', L'B', L'C', L'D', L'E', L'F' };

UINTN
EfiValueToHexStr (
  IN  OUT CHAR16  *Buffer, 
  IN  UINT64      Value, 
  IN  UINTN       Flags, 
  IN  UINTN       Width
  )
/*++

Routine Description:

  VSPrint worker function that prints a Value as a hex number in Buffer

Arguments:

  Buffer - Location to place ascii hex string of Value.

  Value  - Hex value to convert to a string in Buffer.

  Flags  - Flags to use in printing Hex string, see file header for details.

  Width  - Width of hex value.

Returns: 

  Number of characters printed.  

--*/
{
  CHAR16  TempBuffer[CHARACTER_NUMBER_FOR_VALUE];
  CHAR16  *TempStr;
  CHAR16  Prefix;
  CHAR16  *BufferPtr;
  UINTN   Count;
  UINTN   Index;

  TempStr = TempBuffer;
  BufferPtr = Buffer;

  //
  // Count starts at one since we will null terminate. Each iteration of the
  // loop picks off one nibble. Oh yea TempStr ends up backwards
  //
  Count = 0;
  
  if (Width > CHARACTER_NUMBER_FOR_VALUE - 1) {
    Width = CHARACTER_NUMBER_FOR_VALUE - 1;
  }

  do {
    //
    // If Width == 0, it means no limit.
    //
    if ((Width != 0) && (Count >= Width)) {
      break;
    }

    Index = ((UINTN)Value & 0xf);
    *(TempStr++) = mHexStr[Index];
    Value = RShiftU64 (Value, 4);
    Count++;
  } while (Value != 0);

  if (Flags & PREFIX_ZERO) {
    Prefix = '0';
  } else { 
    Prefix = ' ';
  }

  Index = Count;
  if (!(Flags & LEFT_JUSTIFY)) {
    for (; Index < Width; Index++) {
      *(TempStr++) = Prefix;
    }
  }

  //
  // Reverse temp string into Buffer.
  //
  while (TempStr != TempBuffer) {
    *(BufferPtr++) = *(--TempStr);
  }  
    
  *BufferPtr = 0;
  return Index;
}


UINTN
EfiValueToString (
  IN  OUT CHAR16  *Buffer, 
  IN  INT64       Value, 
  IN  UINTN       Flags,
  IN  UINTN       Width
  )
/*++

Routine Description:

  VSPrint worker function that prints a Value as a decimal number in Buffer

Arguments:

  Buffer - Location to place ascii decimal number string of Value.

  Value  - Decimal value to convert to a string in Buffer.

  Flags  - Flags to use in printing decimal string, see file header for details.

  Width  - Width of hex value.

Returns: 

  Number of characters printed.  

--*/
{
  CHAR16  TempBuffer[CHARACTER_NUMBER_FOR_VALUE];
  CHAR16  *TempStr;
  CHAR16  *BufferPtr;
  UINTN   Count;
  UINTN   ValueCharNum;
  UINTN   Remainder;
  CHAR16  Prefix;
  UINTN   Index;
  BOOLEAN   ValueIsNegative;

  TempStr = TempBuffer;
  BufferPtr = Buffer;
  Count = 0;
  ValueCharNum = 0;
  ValueIsNegative = FALSE;

  if (Width > CHARACTER_NUMBER_FOR_VALUE - 1) {
    Width = CHARACTER_NUMBER_FOR_VALUE - 1;
  }

  if (Value < 0) {
    *(TempStr++) = '-';
    Value = -Value;
    ValueCharNum++;
    Count++;
    ValueIsNegative = TRUE;
  }

  do {
    //
    // If Width == 0, it means no limit.
    //
    if ((Width != 0) && (Count >= Width)) {
      break;
    }

    Value = (INT64)DivU64x32 ((UINT64)Value, 10, &Remainder);
    *(TempStr++) = (CHAR16)(Remainder + '0');
    ValueCharNum++;
    Count++;
    if ((Flags & COMMA_TYPE) == COMMA_TYPE) {
      if (Value != 0) {
        if ((ValueIsNegative && (ValueCharNum % 3 == 1)) || ((!ValueIsNegative) && (ValueCharNum % 3 == 0))) {
          *(TempStr++) = ',';
          Count++;
        }
      }
    }
  } while (Value != 0);

 if (Flags & PREFIX_ZERO) {
    Prefix = '0';
  } else { 
    Prefix = ' ';
  }                   

  Index = Count;
  if (!(Flags & LEFT_JUSTIFY)) {
    for (; Index < Width; Index++) {
      *(TempStr++) = Prefix;
  }
  }

  //
  // Reverse temp string into Buffer.
  //
  if (Width == 0) {
    while (TempStr != TempBuffer) {
      *(BufferPtr++) = *(--TempStr);
    }  
  } else {
    Index = 0;
    while ((TempStr != TempBuffer) && (Index++ < Width)) {
      *(BufferPtr++) = *(--TempStr);
    }
  } 
  *BufferPtr = 0;
  return Index;
}