MdeModulePkg: Add %u and %lu support for PrintLib and DebugLib.

[mirror_edk2.git] / MdeModulePkg / Library / DxePrintLibPrint2Protocol / PrintLib.c

/** @file
  Instance of Print Library based on gEfiPrint2ProtocolGuid.

  Implement the print library instance by wrap the interface 
  provided in the Print2 protocol. This protocol is defined as the internal
  protocol related to this implementation, not in the public spec. So, this 
  library instance is only for this code base.

Copyright (c) 2009 - 2015, Intel Corporation. All rights reserved.<BR>
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.

**/

#include <Uefi.h>
#include <Base.h>
#include <Protocol/Print2.h>

#include <Library/PrintLib.h>

#include <Library/BaseLib.h>
#include <Library/DebugLib.h>

EFI_PRINT2_PROTOCOL  *mPrint2Protocol = NULL;

/**
  The constructor function caches the pointer to Print2 protocol.
  
  The constructor function locates Print2 protocol from protocol database.
  It will ASSERT() if that operation fails and it will always return EFI_SUCCESS. 

  @param  ImageHandle   The firmware allocated handle for the EFI image.
  @param  SystemTable   A pointer to the EFI System Table.
  
  @retval EFI_SUCCESS   The constructor always returns EFI_SUCCESS.

**/
EFI_STATUS
EFIAPI
PrintLibConstructor (
  IN EFI_HANDLE                ImageHandle,
  IN EFI_SYSTEM_TABLE          *SystemTable
  )
{
  EFI_STATUS                   Status;

  Status = SystemTable->BootServices->LocateProtocol (
                                        &gEfiPrint2ProtocolGuid,
                                        NULL,
                                        (VOID**) &mPrint2Protocol
                                        );
  ASSERT_EFI_ERROR (Status);
  ASSERT (mPrint2Protocol != NULL);

  return Status;
}


/**
  Worker function that converts a VA_LIST to a BASE_LIST based on a Null-terminated 
  format string.

  @param  AsciiFormat     TRUE if Format is an ASCII string.  FALSE if Format is a Unicode string.
  @param  Format          Null-terminated format string.
  @param  VaListMarker    VA_LIST style variable argument list consumed by processing Format.
  @param  BaseListMarker  BASE_LIST style variable argument list consumed by processing Format.
  @param  Size            The size, in bytes, of the BaseListMarker buffer.

  @return The number of bytes in BaseListMarker.  0 if BaseListMarker is too small.

**/
BOOLEAN
DxePrintLibPrint2ProtocolVaListToBaseList (
  IN  BOOLEAN      AsciiFormat,
  IN  CONST CHAR8  *Format,
  IN  VA_LIST      VaListMarker,
  OUT BASE_LIST    BaseListMarker,
  IN  UINTN        Size
  )
{
  BASE_LIST  BaseListStart;
  UINTN      BytesPerFormatCharacter;
  UINTN      FormatMask;
  UINTN      FormatCharacter;
  BOOLEAN    Long;
  BOOLEAN    Done;

  ASSERT (Format         != NULL);
  ASSERT (BaseListMarker != NULL);

  BaseListStart = BaseListMarker;

  if (AsciiFormat) {
    ASSERT (AsciiStrSize (Format) != 0);
    BytesPerFormatCharacter = 1;
    FormatMask = 0xff;
  } else {
    ASSERT (StrSize ((CHAR16 *) Format) != 0);
    BytesPerFormatCharacter = 2;
    FormatMask = 0xffff;
  }

  //
  // Get the first character from the format string
  //
  FormatCharacter = ((*Format & 0xff) | (*(Format + 1) << 8)) & FormatMask;

  while (FormatCharacter != 0) {
    if (FormatCharacter == '%') {
      Long = FALSE;

      //
      // Parse Flags and Width
      //
      for (Done = FALSE; !Done; ) {
        //
        // Get the next character from the format string
        //
        Format += BytesPerFormatCharacter;

        //
        // Get the next character from the format string
        //
        FormatCharacter = ((*Format & 0xff) | (*(Format + 1) << 8)) & FormatMask;

        switch (FormatCharacter) {
        case '.': 
        case '-': 
        case '+': 
        case ' ': 
        case ',': 
        case '0':
        case '1':
        case '2':
        case '3':
        case '4':
        case '5':
        case '6':
        case '7':
        case '8':
        case '9':
          break;
        case 'L':
        case 'l': 
          Long = TRUE;
          break;
        case '*':
          BASE_ARG (BaseListMarker, UINTN) = VA_ARG (VaListMarker, UINTN);
          break;
        case '\0':
          //
          // Make no output if Format string terminates unexpectedly when
          // looking up for flag, width, precision and type. 
          //
          Format -= BytesPerFormatCharacter;
          //
          // break skipped on purpose.
          //
        default:
          Done = TRUE;
          break;
        }
      } 
        
      //
      // Handle each argument type
      //
      switch (FormatCharacter) {
      case 'p':
        if (sizeof (VOID *) > 4) {
          Long = TRUE;
        }
      case 'X':
      case 'x':
      case 'u':
      case 'd':
        if (Long) {
          BASE_ARG (BaseListMarker, INT64) = VA_ARG (VaListMarker, INT64);
        } else {
          BASE_ARG (BaseListMarker, int) = VA_ARG (VaListMarker, int);
        }
        break;
      case 's':
      case 'S':
      case 'a':
      case 'g':
      case 't':
        BASE_ARG (BaseListMarker, VOID *) = VA_ARG (VaListMarker, VOID *);
        break;
      case 'c':
        BASE_ARG (BaseListMarker, UINTN) = VA_ARG (VaListMarker, UINTN);
        break;
      case 'r':
        BASE_ARG (BaseListMarker, RETURN_STATUS) = VA_ARG (VaListMarker, RETURN_STATUS);
        break;
      }
    }

    //
    // If BASE_LIST is larger than Size, then return FALSE
    //
    if ((UINTN)((UINT8 *)BaseListMarker - (UINT8 *)BaseListStart) > Size) {
      return FALSE;
    }

    //
    // Get the next character from the format string
    //
    Format += BytesPerFormatCharacter;

    //
    // Get the next character from the format string
    //
    FormatCharacter = ((*Format & 0xff) | (*(Format + 1) << 8)) & FormatMask;
  }
  return TRUE;
}

/**
  Produces a Null-terminated Unicode string in an output buffer based on 
  a Null-terminated Unicode format string and a VA_LIST argument list
  
  Produces a Null-terminated Unicode string in the output buffer specified by StartOfBuffer
  and BufferSize.  
  The Unicode string is produced by parsing the format string specified by FormatString.  
  Arguments are pulled from the variable argument list specified by Marker based on the 
  contents of the format string.  
  The number of Unicode characters in the produced output buffer is returned not including
  the Null-terminator.
  If BufferSize is 0 or 1, then no output buffer is produced and 0 is returned.

  If BufferSize > 1 and StartOfBuffer is NULL, then ASSERT().
  If BufferSize > 1 and StartOfBuffer is not aligned on a 16-bit boundary, then ASSERT().
  If BufferSize > 1 and FormatString is NULL, then ASSERT().
  If BufferSize > 1 and FormatString is not aligned on a 16-bit boundary, then ASSERT().
  If PcdMaximumUnicodeStringLength is not zero, and FormatString contains more than 
  PcdMaximumUnicodeStringLength Unicode characters not including the Null-terminator, then
  ASSERT().
  If PcdMaximumUnicodeStringLength is not zero, and produced Null-terminated Unicode string
  contains more than PcdMaximumUnicodeStringLength Unicode characters not including the
  Null-terminator, then ASSERT().

  @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated 
                          Unicode string.
  @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
  @param  FormatString    Null-terminated Unicode format string.
  @param  Marker          VA_LIST marker for the variable argument list.
  
  @return The number of Unicode characters in the produced output buffer not including the
          Null-terminator.

**/
UINTN
EFIAPI
UnicodeVSPrint (
  OUT CHAR16        *StartOfBuffer,
  IN  UINTN         BufferSize,
  IN  CONST CHAR16  *FormatString,
  IN  VA_LIST       Marker
  )
{
  UINT64  BaseListMarker[256 / sizeof (UINT64)];

  DxePrintLibPrint2ProtocolVaListToBaseList (
    FALSE, 
    (CHAR8 *)FormatString, 
    Marker, 
    (BASE_LIST)BaseListMarker, 
    sizeof (BaseListMarker) - 8
    );

  return UnicodeBSPrint (StartOfBuffer, BufferSize, FormatString, (BASE_LIST)BaseListMarker);
}

/**
  Produces a Null-terminated Unicode string in an output buffer based on 
  a Null-terminated Unicode format string and a BASE_LIST argument list
  
  Produces a Null-terminated Unicode string in the output buffer specified by StartOfBuffer
  and BufferSize.  
  The Unicode string is produced by parsing the format string specified by FormatString.  
  Arguments are pulled from the variable argument list specified by Marker based on the 
  contents of the format string.  
  The number of Unicode characters in the produced output buffer is returned not including
  the Null-terminator.
  If BufferSize is 0 or 1, then no output buffer is produced and 0 is returned.

  If BufferSize > 1 and StartOfBuffer is NULL, then ASSERT().
  If BufferSize > 1 and StartOfBuffer is not aligned on a 16-bit boundary, then ASSERT().
  If BufferSize > 1 and FormatString is NULL, then ASSERT().
  If BufferSize > 1 and FormatString is not aligned on a 16-bit boundary, then ASSERT().
  If PcdMaximumUnicodeStringLength is not zero, and FormatString contains more than 
  PcdMaximumUnicodeStringLength Unicode characters not including the Null-terminator, then
  ASSERT().
  If PcdMaximumUnicodeStringLength is not zero, and produced Null-terminated Unicode string
  contains more than PcdMaximumUnicodeStringLength Unicode characters not including the
  Null-terminator, then ASSERT().

  @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated 
                          Unicode string.
  @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
  @param  FormatString    Null-terminated Unicode format string.
  @param  Marker          BASE_LIST marker for the variable argument list.
  
  @return The number of Unicode characters in the produced output buffer not including the
          Null-terminator.

**/
UINTN
EFIAPI
UnicodeBSPrint (
  OUT CHAR16        *StartOfBuffer,
  IN  UINTN         BufferSize,
  IN  CONST CHAR16  *FormatString,
  IN  BASE_LIST     Marker
  )
{
  return mPrint2Protocol->UnicodeBSPrint (StartOfBuffer, BufferSize, FormatString, Marker);
}

/**
  Produces a Null-terminated Unicode string in an output buffer based on a Null-terminated 
  Unicode format string and variable argument list.
  
  Produces a Null-terminated Unicode string in the output buffer specified by StartOfBuffer
  and BufferSize.
  The Unicode string is produced by parsing the format string specified by FormatString.
  Arguments are pulled from the variable argument list based on the contents of the format string.
  The number of Unicode characters in the produced output buffer is returned not including
  the Null-terminator.
  If BufferSize is 0 or 1, then no output buffer is produced and 0 is returned.

  If BufferSize > 1 and StartOfBuffer is NULL, then ASSERT().
  If BufferSize > 1 and StartOfBuffer is not aligned on a 16-bit boundary, then ASSERT().
  If BufferSize > 1 and FormatString is NULL, then ASSERT().
  If BufferSize > 1 and FormatString is not aligned on a 16-bit boundary, then ASSERT().
  If PcdMaximumUnicodeStringLength is not zero, and FormatString contains more than 
  PcdMaximumUnicodeStringLength Unicode characters not including the Null-terminator, then
  ASSERT().
  If PcdMaximumUnicodeStringLength is not zero, and produced Null-terminated Unicode string
  contains more than PcdMaximumUnicodeStringLength Unicode characters not including the
  Null-terminator, then ASSERT().

  @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated 
                          Unicode string.
  @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
  @param  FormatString    Null-terminated Unicode format string.
  @param  ...             Variable argument list whose contents are accessed based on the 
                          format string specified by FormatString.

  @return The number of Unicode characters in the produced output buffer not including the
          Null-terminator.

**/
UINTN
EFIAPI
UnicodeSPrint (
  OUT CHAR16        *StartOfBuffer,
  IN  UINTN         BufferSize,
  IN  CONST CHAR16  *FormatString,
  ...
  )
{
  VA_LIST Marker;
  UINTN   NumberOfPrinted;

  VA_START (Marker, FormatString);
  NumberOfPrinted = UnicodeVSPrint (StartOfBuffer, BufferSize, FormatString, Marker);
  VA_END (Marker);
  return NumberOfPrinted;
}

/**
  Produces a Null-terminated Unicode string in an output buffer based on a Null-terminated
  ASCII format string and a VA_LIST argument list
  
  Produces a Null-terminated Unicode string in the output buffer specified by StartOfBuffer
  and BufferSize.
  The Unicode string is produced by parsing the format string specified by FormatString.
  Arguments are pulled from the variable argument list specified by Marker based on the 
  contents of the format string.
  The number of Unicode characters in the produced output buffer is returned not including
  the Null-terminator.
  If BufferSize is 0 or 1, then no output buffer is produced and 0 is returned.

  If BufferSize > 1 and StartOfBuffer is NULL, then ASSERT().
  If BufferSize > 1 and StartOfBuffer is not aligned on a 16-bit boundary, then ASSERT().
  If BufferSize > 1 and FormatString is NULL, then ASSERT().
  If PcdMaximumAsciiStringLength is not zero, and FormatString contains more than
  PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator, then
  ASSERT().
  If PcdMaximumUnicodeStringLength is not zero, and produced Null-terminated Unicode string
  contains more than PcdMaximumUnicodeStringLength Unicode characters not including the
  Null-terminator, then ASSERT().

  @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated 
                          Unicode string.
  @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
  @param  FormatString    Null-terminated Unicode format string.
  @param  Marker          VA_LIST marker for the variable argument list.
  
  @return The number of Unicode characters in the produced output buffer not including the
          Null-terminator.

**/
UINTN
EFIAPI
UnicodeVSPrintAsciiFormat (
  OUT CHAR16       *StartOfBuffer,
  IN  UINTN        BufferSize,
  IN  CONST CHAR8  *FormatString,
  IN  VA_LIST      Marker
  )
{
  UINT64  BaseListMarker[256 / sizeof (UINT64)];

  DxePrintLibPrint2ProtocolVaListToBaseList (
    TRUE, 
    FormatString, 
    Marker, 
    (BASE_LIST)BaseListMarker, 
    sizeof (BaseListMarker) - 8
    );

  return UnicodeBSPrintAsciiFormat (StartOfBuffer, BufferSize, FormatString, (BASE_LIST)BaseListMarker);
}

/**
  Produces a Null-terminated Unicode string in an output buffer based on a Null-terminated
  ASCII format string and a BASE_LIST argument list
  
  Produces a Null-terminated Unicode string in the output buffer specified by StartOfBuffer
  and BufferSize.
  The Unicode string is produced by parsing the format string specified by FormatString.
  Arguments are pulled from the variable argument list specified by Marker based on the 
  contents of the format string.
  The number of Unicode characters in the produced output buffer is returned not including
  the Null-terminator.
  If BufferSize is 0 or 1, then no output buffer is produced and 0 is returned.

  If BufferSize > 1 and StartOfBuffer is NULL, then ASSERT().
  If BufferSize > 1 and StartOfBuffer is not aligned on a 16-bit boundary, then ASSERT().
  If BufferSize > 1 and FormatString is NULL, then ASSERT().
  If PcdMaximumAsciiStringLength is not zero, and FormatString contains more than
  PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator, then
  ASSERT().
  If PcdMaximumUnicodeStringLength is not zero, and produced Null-terminated Unicode string
  contains more than PcdMaximumUnicodeStringLength Unicode characters not including the
  Null-terminator, then ASSERT().

  @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated 
                          Unicode string.
  @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
  @param  FormatString    Null-terminated Unicode format string.
  @param  Marker          BASE_LIST marker for the variable argument list.
  
  @return The number of Unicode characters in the produced output buffer not including the
          Null-terminator.

**/
UINTN
EFIAPI
UnicodeBSPrintAsciiFormat (
  OUT CHAR16       *StartOfBuffer,
  IN  UINTN        BufferSize,
  IN  CONST CHAR8  *FormatString,
  IN  BASE_LIST    Marker
  )
{
  return mPrint2Protocol->UnicodeBSPrintAsciiFormat (StartOfBuffer, BufferSize, FormatString, Marker);
}

/**
  Produces a Null-terminated Unicode string in an output buffer based on a Null-terminated 
  ASCII format string and  variable argument list.
  
  Produces a Null-terminated Unicode string in the output buffer specified by StartOfBuffer
  and BufferSize.
  The Unicode string is produced by parsing the format string specified by FormatString.
  Arguments are pulled from the variable argument list based on the contents of the 
  format string.
  The number of Unicode characters in the produced output buffer is returned not including
  the Null-terminator.
  If BufferSize is 0 or 1, then no output buffer is produced and 0 is returned.

  If BufferSize > 1 and StartOfBuffer is NULL, then ASSERT().
  If BufferSize > 1 and StartOfBuffer is not aligned on a 16-bit boundary, then ASSERT().
  If BufferSize > 1 and FormatString is NULL, then ASSERT().
  If PcdMaximumAsciiStringLength is not zero, and FormatString contains more than
  PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator, then
  ASSERT().
  If PcdMaximumUnicodeStringLength is not zero, and produced Null-terminated Unicode string
  contains more than PcdMaximumUnicodeStringLength Unicode characters not including the
  Null-terminator, then ASSERT().

  @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated 
                          Unicode string.
  @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
  @param  FormatString    Null-terminated Unicode format string.
  @param  ...             Variable argument list whose contents are accessed based on the 
                          format string specified by FormatString.
  
  @return The number of Unicode characters in the produced output buffer not including the
          Null-terminator.

**/
UINTN
EFIAPI
UnicodeSPrintAsciiFormat (
  OUT CHAR16       *StartOfBuffer,
  IN  UINTN        BufferSize,
  IN  CONST CHAR8  *FormatString,
  ...
  )
{
  VA_LIST Marker;
  UINTN   NumberOfPrinted;

  VA_START (Marker, FormatString);
  NumberOfPrinted = UnicodeVSPrintAsciiFormat (StartOfBuffer, BufferSize, FormatString, Marker);
  VA_END (Marker);
  return NumberOfPrinted;
}

/**
  Converts a decimal value to a Null-terminated Unicode string.
  
  Converts the decimal number specified by Value to a Null-terminated Unicode 
  string specified by Buffer containing at most Width characters. No padding of spaces 
  is ever performed. If Width is 0 then a width of MAXIMUM_VALUE_CHARACTERS is assumed.
  The number of Unicode characters in Buffer is returned not including the Null-terminator.
  If the conversion contains more than Width characters, then only the first
  Width characters are returned, and the total number of characters 
  required to perform the conversion is returned.
  Additional conversion parameters are specified in Flags.  
  
  The Flags bit LEFT_JUSTIFY is always ignored.
  All conversions are left justified in Buffer.
  If Width is 0, PREFIX_ZERO is ignored in Flags.
  If COMMA_TYPE is set in Flags, then PREFIX_ZERO is ignored in Flags, and commas
  are inserted every 3rd digit starting from the right.
  If RADIX_HEX is set in Flags, then the output buffer will be 
  formatted in hexadecimal format.
  If Value is < 0 and RADIX_HEX is not set in Flags, then the fist character in Buffer is a '-'.
  If PREFIX_ZERO is set in Flags and PREFIX_ZERO is not being ignored, 
  then Buffer is padded with '0' characters so the combination of the optional '-' 
  sign character, '0' characters, digit characters for Value, and the Null-terminator
  add up to Width characters.
  If both COMMA_TYPE and RADIX_HEX are set in Flags, then ASSERT().
  If Buffer is NULL, then ASSERT().
  If Buffer is not aligned on a 16-bit boundary, then ASSERT().
  If unsupported bits are set in Flags, then ASSERT().
  If both COMMA_TYPE and RADIX_HEX are set in Flags, then ASSERT().
  If Width >= MAXIMUM_VALUE_CHARACTERS, then ASSERT()

  @param  Buffer  Pointer to the output buffer for the produced Null-terminated
                  Unicode string.
  @param  Flags   The bitmask of flags that specify left justification, zero pad, and commas.
  @param  Value   The 64-bit signed value to convert to a string.
  @param  Width   The maximum number of Unicode characters to place in Buffer, not including
                  the Null-terminator.
  
  @return The number of Unicode characters in Buffer not including the Null-terminator.

**/
UINTN
EFIAPI
UnicodeValueToString (
  IN OUT CHAR16  *Buffer,
  IN UINTN       Flags,
  IN INT64       Value,
  IN UINTN       Width
  )
{
  return mPrint2Protocol->UnicodeValueToString (Buffer, Flags, Value, Width);
}

/**
  Produces a Null-terminated ASCII string in an output buffer based on a Null-terminated
  ASCII format string and a VA_LIST argument list.
  
  Produces a Null-terminated ASCII string in the output buffer specified by StartOfBuffer
  and BufferSize.
  The ASCII string is produced by parsing the format string specified by FormatString.
  Arguments are pulled from the variable argument list specified by Marker based on 
  the contents of the format string.
  The number of ASCII characters in the produced output buffer is returned not including
  the Null-terminator.
  If BufferSize is 0, then no output buffer is produced and 0 is returned.

  If BufferSize > 0 and StartOfBuffer is NULL, then ASSERT().
  If BufferSize > 0 and FormatString is NULL, then ASSERT().
  If PcdMaximumAsciiStringLength is not zero, and FormatString contains more than
  PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator, then
  ASSERT().
  If PcdMaximumAsciiStringLength is not zero, and produced Null-terminated ASCII string
  contains more than PcdMaximumAsciiStringLength ASCII characters not including the
  Null-terminator, then ASSERT().

  @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated 
                          ASCII string.
  @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
  @param  FormatString    Null-terminated Unicode format string.
  @param  Marker          VA_LIST marker for the variable argument list.
  
  @return The number of ASCII characters in the produced output buffer not including the
          Null-terminator.

**/
UINTN
EFIAPI
AsciiVSPrint (
  OUT CHAR8         *StartOfBuffer,
  IN  UINTN         BufferSize,
  IN  CONST CHAR8   *FormatString,
  IN  VA_LIST       Marker
  )
{
  UINT64  BaseListMarker[256 / sizeof (UINT64)];

  DxePrintLibPrint2ProtocolVaListToBaseList (
    TRUE, 
    FormatString, 
    Marker, 
    (BASE_LIST)BaseListMarker, 
    sizeof (BaseListMarker) - 8
    );

  return AsciiBSPrint (StartOfBuffer, BufferSize, FormatString, (BASE_LIST)BaseListMarker);
}

/**
  Produces a Null-terminated ASCII string in an output buffer based on a Null-terminated
  ASCII format string and a BASE_LIST argument list.
  
  Produces a Null-terminated ASCII string in the output buffer specified by StartOfBuffer
  and BufferSize.
  The ASCII string is produced by parsing the format string specified by FormatString.
  Arguments are pulled from the variable argument list specified by Marker based on 
  the contents of the format string.
  The number of ASCII characters in the produced output buffer is returned not including
  the Null-terminator.
  If BufferSize is 0, then no output buffer is produced and 0 is returned.

  If BufferSize > 0 and StartOfBuffer is NULL, then ASSERT().
  If BufferSize > 0 and FormatString is NULL, then ASSERT().
  If PcdMaximumAsciiStringLength is not zero, and FormatString contains more than
  PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator, then
  ASSERT().
  If PcdMaximumAsciiStringLength is not zero, and produced Null-terminated ASCII string
  contains more than PcdMaximumAsciiStringLength ASCII characters not including the
  Null-terminator, then ASSERT().

  @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated 
                          ASCII string.
  @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
  @param  FormatString    Null-terminated Unicode format string.
  @param  Marker          BASE_LIST marker for the variable argument list.
  
  @return The number of ASCII characters in the produced output buffer not including the
          Null-terminator.

**/
UINTN
EFIAPI
AsciiBSPrint (
  OUT CHAR8         *StartOfBuffer,
  IN  UINTN         BufferSize,
  IN  CONST CHAR8   *FormatString,
  IN  BASE_LIST     Marker
  )
{
  return mPrint2Protocol->AsciiBSPrint (StartOfBuffer, BufferSize, FormatString, Marker);
}

/**
  Produces a Null-terminated ASCII string in an output buffer based on a Null-terminated
  ASCII format string and  variable argument list.
  
  Produces a Null-terminated ASCII string in the output buffer specified by StartOfBuffer
  and BufferSize.
  The ASCII string is produced by parsing the format string specified by FormatString.
  Arguments are pulled from the variable argument list based on the contents of the 
  format string.
  The number of ASCII characters in the produced output buffer is returned not including
  the Null-terminator.
  If BufferSize is 0, then no output buffer is produced and 0 is returned.

  If BufferSize > 0 and StartOfBuffer is NULL, then ASSERT().
  If BufferSize > 0 and FormatString is NULL, then ASSERT().
  If PcdMaximumAsciiStringLength is not zero, and FormatString contains more than
  PcdMaximumAsciiStringLength ASCII characters not including the Null-terminator, then
  ASSERT().
  If PcdMaximumAsciiStringLength is not zero, and produced Null-terminated ASCII string
  contains more than PcdMaximumAsciiStringLength ASCII characters not including the
  Null-terminator, then ASSERT().

  @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated 
                          ASCII string.
  @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
  @param  FormatString    Null-terminated Unicode format string.
  @param  ...             Variable argument list whose contents are accessed based on the 
                          format string specified by FormatString.

  @return The number of ASCII characters in the produced output buffer not including the
          Null-terminator.

**/
UINTN
EFIAPI
AsciiSPrint (
  OUT CHAR8        *StartOfBuffer,
  IN  UINTN        BufferSize,
  IN  CONST CHAR8  *FormatString,
  ...
  )
{
  VA_LIST Marker;
  UINTN   NumberOfPrinted;

  VA_START (Marker, FormatString);
  NumberOfPrinted = AsciiVSPrint (StartOfBuffer, BufferSize, FormatString, Marker);
  VA_END (Marker);
  return NumberOfPrinted;
}

/**
  Produces a Null-terminated ASCII string in an output buffer based on a Null-terminated
  ASCII format string and a VA_LIST argument list.
  
  Produces a Null-terminated ASCII string in the output buffer specified by StartOfBuffer
  and BufferSize.
  The ASCII string is produced by parsing the format string specified by FormatString.
  Arguments are pulled from the variable argument list specified by Marker based on 
  the contents of the format string.
  The number of ASCII characters in the produced output buffer is returned not including
  the Null-terminator.
  If BufferSize is 0, then no output buffer is produced and 0 is returned.

  If BufferSize > 0 and StartOfBuffer is NULL, then ASSERT().
  If BufferSize > 0 and FormatString is NULL, then ASSERT().
  If BufferSize > 0 and FormatString is not aligned on a 16-bit boundary, then ASSERT().
  If PcdMaximumUnicodeStringLength is not zero, and FormatString contains more than
  PcdMaximumUnicodeStringLength Unicode characters not including the Null-terminator, then
  ASSERT().
  If PcdMaximumAsciiStringLength is not zero, and produced Null-terminated ASCII string
  contains more than PcdMaximumAsciiStringLength ASCII characters not including the
  Null-terminator, then ASSERT().

  @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated 
                          ASCII string.
  @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
  @param  FormatString    Null-terminated Unicode format string.
  @param  Marker          VA_LIST marker for the variable argument list.
  
  @return The number of ASCII characters in the produced output buffer not including the
          Null-terminator.

**/
UINTN
EFIAPI
AsciiVSPrintUnicodeFormat (
  OUT CHAR8         *StartOfBuffer,
  IN  UINTN         BufferSize,
  IN  CONST CHAR16  *FormatString,
  IN  VA_LIST       Marker
  )
{
  UINT64  BaseListMarker[256 / sizeof (UINT64)];

  DxePrintLibPrint2ProtocolVaListToBaseList (
    FALSE, 
    (CHAR8 *)FormatString, 
    Marker, 
    (BASE_LIST)BaseListMarker, 
    sizeof (BaseListMarker) - 8
    );

  return AsciiBSPrintUnicodeFormat (StartOfBuffer, BufferSize, FormatString, (BASE_LIST)BaseListMarker);
}

/**
  Produces a Null-terminated ASCII string in an output buffer based on a Null-terminated
  ASCII format string and a BASE_LIST argument list.
  
  Produces a Null-terminated ASCII string in the output buffer specified by StartOfBuffer
  and BufferSize.
  The ASCII string is produced by parsing the format string specified by FormatString.
  Arguments are pulled from the variable argument list specified by Marker based on 
  the contents of the format string.
  The number of ASCII characters in the produced output buffer is returned not including
  the Null-terminator.
  If BufferSize is 0, then no output buffer is produced and 0 is returned.

  If BufferSize > 0 and StartOfBuffer is NULL, then ASSERT().
  If BufferSize > 0 and FormatString is NULL, then ASSERT().
  If BufferSize > 0 and FormatString is not aligned on a 16-bit boundary, then ASSERT().
  If PcdMaximumUnicodeStringLength is not zero, and FormatString contains more than
  PcdMaximumUnicodeStringLength Unicode characters not including the Null-terminator, then
  ASSERT().
  If PcdMaximumAsciiStringLength is not zero, and produced Null-terminated ASCII string
  contains more than PcdMaximumAsciiStringLength ASCII characters not including the
  Null-terminator, then ASSERT().

  @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated 
                          ASCII string.
  @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
  @param  FormatString    Null-terminated Unicode format string.
  @param  Marker          BASE_LIST marker for the variable argument list.
  
  @return The number of ASCII characters in the produced output buffer not including the
          Null-terminator.

**/
UINTN
EFIAPI
AsciiBSPrintUnicodeFormat (
  OUT CHAR8         *StartOfBuffer,
  IN  UINTN         BufferSize,
  IN  CONST CHAR16  *FormatString,
  IN  BASE_LIST     Marker
  )
{
  return mPrint2Protocol->AsciiBSPrintUnicodeFormat (StartOfBuffer, BufferSize, FormatString, Marker);
}

/**
  Produces a Null-terminated ASCII string in an output buffer based on a Null-terminated
  ASCII format string and  variable argument list.
  
  Produces a Null-terminated ASCII string in the output buffer specified by StartOfBuffer
  and BufferSize.
  The ASCII string is produced by parsing the format string specified by FormatString.
  Arguments are pulled from the variable argument list based on the contents of the 
  format string.
  The number of ASCII characters in the produced output buffer is returned not including
  the Null-terminator.
  If BufferSize is 0, then no output buffer is produced and 0 is returned.

  If BufferSize > 0 and StartOfBuffer is NULL, then ASSERT().
  If BufferSize > 0 and FormatString is NULL, then ASSERT().
  If BufferSize > 0 and FormatString is not aligned on a 16-bit boundary, then ASSERT().
  If PcdMaximumUnicodeStringLength is not zero, and FormatString contains more than
  PcdMaximumUnicodeStringLength Unicode characters not including the Null-terminator, then
  ASSERT().
  If PcdMaximumAsciiStringLength is not zero, and produced Null-terminated ASCII string
  contains more than PcdMaximumAsciiStringLength ASCII characters not including the
  Null-terminator, then ASSERT().

  @param  StartOfBuffer   A pointer to the output buffer for the produced Null-terminated 
                          ASCII string.
  @param  BufferSize      The size, in bytes, of the output buffer specified by StartOfBuffer.
  @param  FormatString    Null-terminated Unicode format string.
  @param  ...             Variable argument list whose contents are accessed based on the 
                          format string specified by FormatString.

  @return The number of ASCII characters in the produced output buffer not including the
          Null-terminator.

**/
UINTN
EFIAPI
AsciiSPrintUnicodeFormat (
  OUT CHAR8         *StartOfBuffer,
  IN  UINTN         BufferSize,
  IN  CONST CHAR16  *FormatString,
  ...
  )
{
  VA_LIST Marker;
  UINTN   NumberOfPrinted;

  VA_START (Marker, FormatString);
  NumberOfPrinted = AsciiVSPrintUnicodeFormat (StartOfBuffer, BufferSize, FormatString, Marker);
  VA_END (Marker);
  return NumberOfPrinted;
}


/**
  Converts a decimal value to a Null-terminated ASCII string.
  
  Converts the decimal number specified by Value to a Null-terminated ASCII string 
  specified by Buffer containing at most Width characters. No padding of spaces 
  is ever performed.
  If Width is 0 then a width of  MAXIMUM_VALUE_CHARACTERS is assumed.
  The number of ASCII characters in Buffer is returned not including the Null-terminator.
  If the conversion contains more than Width characters, then only the first Width
  characters are returned, and the total number of characters required to perform
  the conversion is returned.
  Additional conversion parameters are specified in Flags.  
  The Flags bit LEFT_JUSTIFY is always ignored.
  All conversions are left justified in Buffer.
  If Width is 0, PREFIX_ZERO is ignored in Flags.
  If COMMA_TYPE is set in Flags, then PREFIX_ZERO is ignored in Flags, and commas
  are inserted every 3rd digit starting from the right.
  If RADIX_HEX is set in Flags, then the output buffer will be 
  formatted in hexadecimal format.
  If Value is < 0 and RADIX_HEX is not set in Flags, then the fist character in Buffer is a '-'.
  If PREFIX_ZERO is set in Flags and PREFIX_ZERO is not being ignored, 
  then Buffer is padded with '0' characters so the combination of the optional '-' 
  sign character, '0' characters, digit characters for Value, and the Null-terminator
  add up to Width characters.
  
  If Buffer is NULL, then ASSERT().
  If unsupported bits are set in Flags, then ASSERT().
  If both COMMA_TYPE and RADIX_HEX are set in Flags, then ASSERT().
  If Width >= MAXIMUM_VALUE_CHARACTERS, then ASSERT()

  @param  Buffer  Pointer to the output buffer for the produced Null-terminated
                  ASCII string.
  @param  Flags   The bitmask of flags that specify left justification, zero pad, and commas.
  @param  Value   The 64-bit signed value to convert to a string.
  @param  Width   The maximum number of ASCII characters to place in Buffer, not including
                  the Null-terminator.
  
  @return The number of ASCII characters in Buffer not including the Null-terminator.

**/
UINTN
EFIAPI
AsciiValueToString (
  OUT CHAR8      *Buffer,
  IN  UINTN      Flags,
  IN  INT64      Value,
  IN  UINTN      Width
  )
{
  return mPrint2Protocol->AsciiValueToString (Buffer, Flags, Value, Width);
}

#define PREFIX_SIGN           BIT1
#define PREFIX_BLANK          BIT2
#define LONG_TYPE             BIT4
#define OUTPUT_UNICODE        BIT6
#define FORMAT_UNICODE        BIT8
#define PAD_TO_WIDTH          BIT9
#define ARGUMENT_UNICODE      BIT10
#define PRECISION             BIT11
#define ARGUMENT_REVERSED     BIT12
#define COUNT_ONLY_NO_PRINT   BIT13
#define UNSIGNED_TYPE         BIT14

//
// Record date and time information
//
typedef struct {
  UINT16  Year;
  UINT8   Month;
  UINT8   Day;
  UINT8   Hour;
  UINT8   Minute;
  UINT8   Second;
  UINT8   Pad1;
  UINT32  Nanosecond;
  INT16   TimeZone;
  UINT8   Daylight;
  UINT8   Pad2;
} TIME;

GLOBAL_REMOVE_IF_UNREFERENCED CONST CHAR8 mHexStr[] = {'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};

/**
  Internal function that convert a number to a string in Buffer.

  Print worker function that converts a decimal or hexadecimal number to an ASCII string in Buffer.

  @param  Buffer    Location to place the ASCII string of Value.
  @param  Value     The value to convert to a Decimal or Hexadecimal string in Buffer.
  @param  Radix     Radix of the value

  @return A pointer to the end of buffer filled with ASCII string.

**/
CHAR8 *
InternalPrintLibValueToString (
  IN OUT CHAR8  *Buffer, 
  IN INT64      Value, 
  IN UINTN      Radix
  )
{
  UINT32  Remainder;

  //
  // Loop to convert one digit at a time in reverse order
  //
  *Buffer = 0;
  do {
    Value = (INT64)DivU64x32Remainder ((UINT64)Value, (UINT32)Radix, &Remainder);
    *(++Buffer) = mHexStr[Remainder];
  } while (Value != 0);

  //
  // Return pointer of the end of filled buffer.
  //
  return Buffer;
}

/**
  Worker function that produces a Null-terminated string in an output buffer 
  based on a Null-terminated format string and a VA_LIST argument list.

  VSPrint function to process format and place the results in Buffer. Since a 
  VA_LIST is used this routine allows the nesting of Vararg routines. Thus 
  this is the main print working routine.

  If COUNT_ONLY_NO_PRINT is set in Flags, Buffer will not be modified at all.

  @param[out] Buffer          The character buffer to print the results of the 
                              parsing of Format into.
  @param[in]  BufferSize      The maximum number of characters to put into 
                              buffer.
  @param[in]  Flags           Initial flags value.
                              Can only have FORMAT_UNICODE, OUTPUT_UNICODE, 
                              and COUNT_ONLY_NO_PRINT set.
  @param[in]  Format          A Null-terminated format string.
  @param[in]  VaListMarker    VA_LIST style variable argument list consumed by
                              processing Format.
  @param[in]  BaseListMarker  BASE_LIST style variable argument list consumed
                              by processing Format.

  @return The number of characters printed not including the Null-terminator.
          If COUNT_ONLY_NO_PRINT was set returns the same, but without any
          modification to Buffer.

**/
UINTN
InternalPrintLibSPrintMarker (
  OUT CHAR8        *Buffer,
  IN  UINTN        BufferSize,
  IN  UINTN        Flags,
  IN  CONST CHAR8  *Format,
  IN  VA_LIST      VaListMarker,   OPTIONAL
  IN  BASE_LIST    BaseListMarker  OPTIONAL
  );

/**
  Worker function that produces a Null-terminated string in an output buffer 
  based on a Null-terminated format string and variable argument list.

  VSPrint function to process format and place the results in Buffer. Since a 
  VA_LIST is used this routine allows the nesting of Vararg routines. Thus 
  this is the main print working routine

  @param  StartOfBuffer The character buffer to print the results of the parsing
                        of Format into.
  @param  BufferSize    The maximum number of characters to put into buffer.
                        Zero means no limit.
  @param  Flags         Initial flags value.
                        Can only have FORMAT_UNICODE and OUTPUT_UNICODE set
  @param  FormatString  A Null-terminated format string.
  @param  ...           The variable argument list.

  @return The number of characters printed.

**/
UINTN
EFIAPI
InternalPrintLibSPrint (
  OUT CHAR8        *StartOfBuffer,
  IN  UINTN        BufferSize,
  IN  UINTN        Flags,
  IN  CONST CHAR8  *FormatString,
  ...
  )
{
  VA_LIST  Marker;
  UINTN    NumberOfPrinted;

  VA_START (Marker, FormatString);
  NumberOfPrinted = InternalPrintLibSPrintMarker (StartOfBuffer, BufferSize, Flags, FormatString, Marker, NULL);
  VA_END (Marker);
  return NumberOfPrinted;
}

#define WARNING_STATUS_NUMBER         5
#define ERROR_STATUS_NUMBER           33

GLOBAL_REMOVE_IF_UNREFERENCED CONST CHAR8 *mStatusString[] = {
  "Success",                      //  RETURN_SUCCESS                = 0
  "Warning Unknown Glyph",        //  RETURN_WARN_UNKNOWN_GLYPH     = 1
  "Warning Delete Failure",       //  RETURN_WARN_DELETE_FAILURE    = 2
  "Warning Write Failure",        //  RETURN_WARN_WRITE_FAILURE     = 3
  "Warning Buffer Too Small",     //  RETURN_WARN_BUFFER_TOO_SMALL  = 4
  "Warning Stale Data",           //  RETURN_WARN_STALE_DATA        = 5
  "Load Error",                   //  RETURN_LOAD_ERROR             = 1  | MAX_BIT
  "Invalid Parameter",            //  RETURN_INVALID_PARAMETER      = 2  | MAX_BIT
  "Unsupported",                  //  RETURN_UNSUPPORTED            = 3  | MAX_BIT
  "Bad Buffer Size",              //  RETURN_BAD_BUFFER_SIZE        = 4  | MAX_BIT
  "Buffer Too Small",             //  RETURN_BUFFER_TOO_SMALL,      = 5  | MAX_BIT
  "Not Ready",                    //  RETURN_NOT_READY              = 6  | MAX_BIT
  "Device Error",                 //  RETURN_DEVICE_ERROR           = 7  | MAX_BIT
  "Write Protected",              //  RETURN_WRITE_PROTECTED        = 8  | MAX_BIT
  "Out of Resources",             //  RETURN_OUT_OF_RESOURCES       = 9  | MAX_BIT
  "Volume Corrupt",               //  RETURN_VOLUME_CORRUPTED       = 10 | MAX_BIT
  "Volume Full",                  //  RETURN_VOLUME_FULL            = 11 | MAX_BIT
  "No Media",                     //  RETURN_NO_MEDIA               = 12 | MAX_BIT
  "Media changed",                //  RETURN_MEDIA_CHANGED          = 13 | MAX_BIT
  "Not Found",                    //  RETURN_NOT_FOUND              = 14 | MAX_BIT
  "Access Denied",                //  RETURN_ACCESS_DENIED          = 15 | MAX_BIT
  "No Response",                  //  RETURN_NO_RESPONSE            = 16 | MAX_BIT
  "No mapping",                   //  RETURN_NO_MAPPING             = 17 | MAX_BIT
  "Time out",                     //  RETURN_TIMEOUT                = 18 | MAX_BIT
  "Not started",                  //  RETURN_NOT_STARTED            = 19 | MAX_BIT
  "Already started",              //  RETURN_ALREADY_STARTED        = 20 | MAX_BIT
  "Aborted",                      //  RETURN_ABORTED                = 21 | MAX_BIT
  "ICMP Error",                   //  RETURN_ICMP_ERROR             = 22 | MAX_BIT
  "TFTP Error",                   //  RETURN_TFTP_ERROR             = 23 | MAX_BIT
  "Protocol Error",               //  RETURN_PROTOCOL_ERROR         = 24 | MAX_BIT
  "Incompatible Version",         //  RETURN_INCOMPATIBLE_VERSION   = 25 | MAX_BIT
  "Security Violation",           //  RETURN_SECURITY_VIOLATION     = 26 | MAX_BIT
  "CRC Error",                    //  RETURN_CRC_ERROR              = 27 | MAX_BIT
  "End of Media",                 //  RETURN_END_OF_MEDIA           = 28 | MAX_BIT
  "Reserved (29)",                //  RESERVED                      = 29 | MAX_BIT
  "Reserved (30)",                //  RESERVED                      = 30 | MAX_BIT
  "End of File",                  //  RETURN_END_OF_FILE            = 31 | MAX_BIT
  "Invalid Language",             //  RETURN_INVALID_LANGUAGE       = 32 | MAX_BIT
  "Compromised Data"              //  RETURN_COMPROMISED_DATA       = 33 | MAX_BIT
};

/**
  Internal function that places the character into the Buffer.

  Internal function that places ASCII or Unicode character into the Buffer.

  @param  Buffer      The buffer to place the Unicode or ASCII string.
  @param  EndBuffer   The end of the input Buffer. No characters will be
                      placed after that. 
  @param  Length      The count of character to be placed into Buffer.
                      (Negative value indicates no buffer fill.)
  @param  Character   The character to be placed into Buffer.
  @param  Increment   The character increment in Buffer.

  @return Buffer.

**/
CHAR8 *
InternalPrintLibFillBuffer (
  OUT CHAR8   *Buffer,
  IN  CHAR8   *EndBuffer,
  IN  INTN    Length,
  IN  UINTN   Character,
  IN  INTN    Increment
  )
{
  INTN  Index;
  
  for (Index = 0; Index < Length && Buffer < EndBuffer; Index++) {
    *Buffer = (CHAR8) Character;
    if (Increment != 1) {
      *(Buffer + 1) = (CHAR8)(Character >> 8);
    }
    Buffer += Increment;
  }

  return Buffer;
}

/**
  Worker function that produces a Null-terminated string in an output buffer 
  based on a Null-terminated format string and a VA_LIST argument list.

  VSPrint function to process format and place the results in Buffer. Since a 
  VA_LIST is used this routine allows the nesting of Vararg routines. Thus 
  this is the main print working routine.

  If COUNT_ONLY_NO_PRINT is set in Flags, Buffer will not be modified at all.

  @param[out] Buffer          The character buffer to print the results of the 
                              parsing of Format into.
  @param[in]  BufferSize      The maximum number of characters to put into 
                              buffer.
  @param[in]  Flags           Initial flags value.
                              Can only have FORMAT_UNICODE, OUTPUT_UNICODE, 
                              and COUNT_ONLY_NO_PRINT set.
  @param[in]  Format          A Null-terminated format string.
  @param[in]  VaListMarker    VA_LIST style variable argument list consumed by
                              processing Format.
  @param[in]  BaseListMarker  BASE_LIST style variable argument list consumed
                              by processing Format.

  @return The number of characters printed not including the Null-terminator.
          If COUNT_ONLY_NO_PRINT was set returns the same, but without any
          modification to Buffer.

**/
UINTN
InternalPrintLibSPrintMarker (
  OUT CHAR8        *Buffer,
  IN  UINTN        BufferSize,
  IN  UINTN        Flags,
  IN  CONST CHAR8  *Format,
  IN  VA_LIST      VaListMarker,   OPTIONAL
  IN  BASE_LIST    BaseListMarker  OPTIONAL
  )
{
  CHAR8             *OriginalBuffer;
  CHAR8             *EndBuffer;
  CHAR8             ValueBuffer[MAXIMUM_VALUE_CHARACTERS];
  UINT32            BytesPerOutputCharacter;
  UINTN             BytesPerFormatCharacter;
  UINTN             FormatMask;
  UINTN             FormatCharacter;
  UINTN             Width;
  UINTN             Precision;
  INT64             Value;
  CONST CHAR8       *ArgumentString;
  UINTN             Character;
  GUID              *TmpGuid;
  TIME              *TmpTime;
  UINTN             Count;
  UINTN             ArgumentMask;
  INTN              BytesPerArgumentCharacter;
  UINTN             ArgumentCharacter;
  BOOLEAN           Done;
  UINTN             Index;
  CHAR8             Prefix;
  BOOLEAN           ZeroPad;
  BOOLEAN           Comma;
  UINTN             Digits;
  UINTN             Radix;
  RETURN_STATUS     Status;
  UINT32            GuidData1;
  UINT16            GuidData2;
  UINT16            GuidData3;
  UINTN             LengthToReturn;

  //
  // If you change this code be sure to match the 2 versions of this function.
  // Nearly identical logic is found in the BasePrintLib and 
  // DxePrintLibPrint2Protocol (both PrintLib instances).
  //

  if ((Flags & COUNT_ONLY_NO_PRINT) != 0) {
    if (BufferSize == 0) {
      Buffer = NULL;
    }
  } else {
    //
    // We can run without a Buffer for counting only.
    //
    if (BufferSize == 0) {
      return 0;
    }
    ASSERT (Buffer != NULL);
  }

  if ((Flags & OUTPUT_UNICODE) != 0) {
    BytesPerOutputCharacter = 2;
  } else {
    BytesPerOutputCharacter = 1;
  }

  LengthToReturn = 0;
  EndBuffer = NULL;
  OriginalBuffer = NULL;

  //
  // Reserve space for the Null terminator.
  //
  if (Buffer != NULL) {
    BufferSize--;
    OriginalBuffer = Buffer;

    //
    // Set the tag for the end of the input Buffer.
    //
    EndBuffer = Buffer + BufferSize * BytesPerOutputCharacter;
  }

  if ((Flags & FORMAT_UNICODE) != 0) {
    //
    // Make sure format string cannot contain more than PcdMaximumUnicodeStringLength
    // Unicode characters if PcdMaximumUnicodeStringLength is not zero. 
    //
    ASSERT (StrSize ((CHAR16 *) Format) != 0);
    BytesPerFormatCharacter = 2;
    FormatMask = 0xffff;
  } else {
    //
    // Make sure format string cannot contain more than PcdMaximumAsciiStringLength
    // Ascii characters if PcdMaximumAsciiStringLength is not zero. 
    //
    ASSERT (AsciiStrSize (Format) != 0);
    BytesPerFormatCharacter = 1;
    FormatMask = 0xff;
  }

  //
  // Get the first character from the format string
  //
  FormatCharacter = ((*Format & 0xff) | (*(Format + 1) << 8)) & FormatMask;

  //
  // Loop until the end of the format string is reached or the output buffer is full
  //
  while (FormatCharacter != 0) {
    if ((Buffer != NULL) && (Buffer >= EndBuffer)) {
      break;
    }
    //
    // Clear all the flag bits except those that may have been passed in
    //
    Flags &= (UINTN) (OUTPUT_UNICODE | FORMAT_UNICODE | COUNT_ONLY_NO_PRINT);

    //
    // Set the default width to zero, and the default precision to 1
    //
    Width     = 0;
    Precision = 1;
    Prefix    = 0;
    Comma     = FALSE;
    ZeroPad   = FALSE;
    Count     = 0;
    Digits    = 0;

    switch (FormatCharacter) {
    case '%':
      //
      // Parse Flags and Width
      //
      for (Done = FALSE; !Done; ) {
        Format += BytesPerFormatCharacter;
        FormatCharacter = ((*Format & 0xff) | (*(Format + 1) << 8)) & FormatMask;
        switch (FormatCharacter) {
        case '.': 
          Flags |= PRECISION; 
          break;
        case '-': 
          Flags |= LEFT_JUSTIFY; 
          break;
        case '+': 
          Flags |= PREFIX_SIGN;  
          break;
        case ' ': 
          Flags |= PREFIX_BLANK; 
          break;
        case ',': 
          Flags |= COMMA_TYPE; 
          break;
        case 'L':
        case 'l': 
          Flags |= LONG_TYPE;    
          break;
        case '*':
          if ((Flags & PRECISION) == 0) {
            Flags |= PAD_TO_WIDTH;
            if (BaseListMarker == NULL) {
              Width = VA_ARG (VaListMarker, UINTN);
            } else {
              Width = BASE_ARG (BaseListMarker, UINTN);
            }
          } else {
            if (BaseListMarker == NULL) {
              Precision = VA_ARG (VaListMarker, UINTN);
            } else {
              Precision = BASE_ARG (BaseListMarker, UINTN);
            }
          }
          break;
        case '0':
          if ((Flags & PRECISION) == 0) {
            Flags |= PREFIX_ZERO;
          }
        case '1':
        case '2':
        case '3':
        case '4':
        case '5':
        case '6':
        case '7':
        case '8':
        case '9':
          for (Count = 0; ((FormatCharacter >= '0') &&  (FormatCharacter <= '9')); ){
            Count = (Count * 10) + FormatCharacter - '0';
            Format += BytesPerFormatCharacter;
            FormatCharacter = ((*Format & 0xff) | (*(Format + 1) << 8)) & FormatMask;
          }
          Format -= BytesPerFormatCharacter;
          if ((Flags & PRECISION) == 0) {
            Flags |= PAD_TO_WIDTH;
            Width = Count;
          } else {
            Precision = Count;
          }
          break;
       
        case '\0':
          //
          // Make no output if Format string terminates unexpectedly when
          // looking up for flag, width, precision and type. 
          //
          Format   -= BytesPerFormatCharacter;
          Precision = 0;
          //
          // break skipped on purpose.
          //
        default:
          Done = TRUE;
          break;
        }
      } 

      //
      // Handle each argument type
      //
      switch (FormatCharacter) {
      case 'p':
        //
        // Flag space, +, 0, L & l are invalid for type p.
        //
        Flags &= ~((UINTN) (PREFIX_BLANK | PREFIX_SIGN | PREFIX_ZERO | LONG_TYPE));
        if (sizeof (VOID *) > 4) {
          Flags |= LONG_TYPE;
        }
        //
        // break skipped on purpose
        //
      case 'X':
        Flags |= PREFIX_ZERO;
        //
        // break skipped on purpose
        //
      case 'x':
        Flags |= RADIX_HEX;
        //
        // break skipped on purpose
        //
      case 'u':
        if ((Flags & RADIX_HEX) == 0) {
          Flags &= ~((UINTN) (PREFIX_SIGN));
          Flags |= UNSIGNED_TYPE;
        }
        //
        // break skipped on purpose
        //
      case 'd':
        if ((Flags & LONG_TYPE) == 0) {
          //
          // 'd', 'u', 'x', and 'X' that are not preceded by 'l' or 'L' are assumed to be type "int".
          // This assumption is made so the format string definition is compatible with the ANSI C
          // Specification for formatted strings.  It is recommended that the Base Types be used 
          // everywhere, but in this one case, compliance with ANSI C is more important, and 
          // provides an implementation that is compatible with that largest possible set of CPU 
          // architectures.  This is why the type "int" is used in this one case.
          //
          if (BaseListMarker == NULL) {
            Value = VA_ARG (VaListMarker, int);
          } else {
            Value = BASE_ARG (BaseListMarker, int);
          }
        } else {
          if (BaseListMarker == NULL) {
            Value = VA_ARG (VaListMarker, INT64);
          } else {
            Value = BASE_ARG (BaseListMarker, INT64);
          }
        }
        if ((Flags & PREFIX_BLANK) != 0) {
          Prefix = ' ';
        }
        if ((Flags & PREFIX_SIGN) != 0) {
          Prefix = '+';
        }
        if ((Flags & COMMA_TYPE) != 0) {
          Comma = TRUE;
        }
        if ((Flags & RADIX_HEX) == 0) {
          Radix = 10;
          if (Comma) {
            Flags &= ~((UINTN) PREFIX_ZERO);
            Precision = 1;
          }
          if (Value < 0 && (Flags & UNSIGNED_TYPE) == 0) {
            Flags |= PREFIX_SIGN;
            Prefix = '-';
            Value = -Value;
          } else if ((Flags & UNSIGNED_TYPE) != 0 && (Flags & LONG_TYPE) == 0) {
            //
            // 'd', 'u', 'x', and 'X' that are not preceded by 'l' or 'L' are assumed to be type "int".
            // This assumption is made so the format string definition is compatible with the ANSI C
            // Specification for formatted strings.  It is recommended that the Base Types be used 
            // everywhere, but in this one case, compliance with ANSI C is more important, and 
            // provides an implementation that is compatible with that largest possible set of CPU 
            // architectures.  This is why the type "unsigned int" is used in this one case.
            //
            Value = (unsigned int)Value;
          }
        } else {
          Radix = 16;
          Comma = FALSE;
          if ((Flags & LONG_TYPE) == 0 && Value < 0) {
            //
            // 'd', 'u', 'x', and 'X' that are not preceded by 'l' or 'L' are assumed to be type "int".
            // This assumption is made so the format string definition is compatible with the ANSI C
            // Specification for formatted strings.  It is recommended that the Base Types be used 
            // everywhere, but in this one case, compliance with ANSI C is more important, and 
            // provides an implementation that is compatible with that largest possible set of CPU 
            // architectures.  This is why the type "unsigned int" is used in this one case.
            //
            Value = (unsigned int)Value;
          }
        }
        //
        // Convert Value to a reversed string
        //
        Count = InternalPrintLibValueToString (ValueBuffer, Value, Radix) - ValueBuffer;
        if (Value == 0 && Precision == 0) {
          Count = 0;
        }
        ArgumentString = (CHAR8 *)ValueBuffer + Count;
        
        Digits = Count % 3;
        if (Digits != 0) {
          Digits = 3 - Digits;
        }
        if (Comma && Count != 0) {
          Count += ((Count - 1) / 3);
        }
        if (Prefix != 0) {
          Count++;
          Precision++;
        }
        Flags |= ARGUMENT_REVERSED;
        ZeroPad = TRUE;
        if ((Flags & PREFIX_ZERO) != 0) {
          if ((Flags & LEFT_JUSTIFY) == 0) {
            if ((Flags & PAD_TO_WIDTH) != 0) {
              if ((Flags & PRECISION) == 0) {
                Precision = Width;
              }
            }
          }
        }
        break;

      case 's':
      case 'S':
        Flags |= ARGUMENT_UNICODE;
        //
        // break skipped on purpose
        //
      case 'a':
        if (BaseListMarker == NULL) {
          ArgumentString = VA_ARG (VaListMarker, CHAR8 *);
        } else {
          ArgumentString = BASE_ARG (BaseListMarker, CHAR8 *);
        }
        if (ArgumentString == NULL) {
          Flags &= (~(UINTN)ARGUMENT_UNICODE);
          ArgumentString = "<null string>";
        }
        //
        // Set the default precision for string to be zero if not specified.
        //
        if ((Flags & PRECISION) == 0) {
          Precision = 0;
        }
        break;

      case 'c':
        if (BaseListMarker == NULL) {
          Character = VA_ARG (VaListMarker, UINTN) & 0xffff;
        } else {
          Character = BASE_ARG (BaseListMarker, UINTN) & 0xffff;
        }
        ArgumentString = (CHAR8 *)&Character;
        Flags |= ARGUMENT_UNICODE;
        break;

      case 'g':
        if (BaseListMarker == NULL) {
          TmpGuid = VA_ARG (VaListMarker, GUID *);
        } else {
          TmpGuid = BASE_ARG (BaseListMarker, GUID *);
        }
        if (TmpGuid == NULL) {
          ArgumentString = "<null guid>";
        } else {
          GuidData1 = ReadUnaligned32 (&(TmpGuid->Data1));
          GuidData2 = ReadUnaligned16 (&(TmpGuid->Data2));
          GuidData3 = ReadUnaligned16 (&(TmpGuid->Data3));
          InternalPrintLibSPrint (
            ValueBuffer,
            MAXIMUM_VALUE_CHARACTERS, 
            0,
            "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
            GuidData1,
            GuidData2,
            GuidData3,
            TmpGuid->Data4[0],
            TmpGuid->Data4[1],
            TmpGuid->Data4[2],
            TmpGuid->Data4[3],
            TmpGuid->Data4[4],
            TmpGuid->Data4[5],
            TmpGuid->Data4[6],
            TmpGuid->Data4[7]
            );
          ArgumentString = ValueBuffer;
        }
        break;

      case 't':
        if (BaseListMarker == NULL) {
          TmpTime = VA_ARG (VaListMarker, TIME *); 
        } else {
          TmpTime = BASE_ARG (BaseListMarker, TIME *); 
        }
        if (TmpTime == NULL) {
          ArgumentString = "<null time>";
        } else {
          InternalPrintLibSPrint (
            ValueBuffer,
            MAXIMUM_VALUE_CHARACTERS,
            0,
            "%02d/%02d/%04d  %02d:%02d",
            TmpTime->Month,
            TmpTime->Day,
            TmpTime->Year,
            TmpTime->Hour,
            TmpTime->Minute
            );
          ArgumentString = ValueBuffer;
        }
        break;

      case 'r':
        if (BaseListMarker == NULL) {
          Status = VA_ARG (VaListMarker, RETURN_STATUS);
        } else {
          Status = BASE_ARG (BaseListMarker, RETURN_STATUS);
        }
        ArgumentString = ValueBuffer;
        if (RETURN_ERROR (Status)) {
          //
          // Clear error bit
          //
          Index = Status & ~MAX_BIT;
          if (Index > 0 && Index <= ERROR_STATUS_NUMBER) {
            ArgumentString = mStatusString [Index + WARNING_STATUS_NUMBER];
          }
        } else {
          Index = Status;
          if (Index <= WARNING_STATUS_NUMBER) {
            ArgumentString = mStatusString [Index];
          }
        }
        if (ArgumentString == ValueBuffer) {
          InternalPrintLibSPrint ((CHAR8 *) ValueBuffer, MAXIMUM_VALUE_CHARACTERS, 0, "%08X", Status);
        }
        break;

      case '\r':
        Format += BytesPerFormatCharacter;
        FormatCharacter = ((*Format & 0xff) | (*(Format + 1) << 8)) & FormatMask;
        if (FormatCharacter == '\n') {
          //
          // Translate '\r\n' to '\r\n'
          //
          ArgumentString = "\r\n";
        } else {
          //
          // Translate '\r' to '\r'
          //
          ArgumentString = "\r";
          Format   -= BytesPerFormatCharacter;
        }
        break;

      case '\n':
        //
        // Translate '\n' to '\r\n' and '\n\r' to '\r\n'
        //
        ArgumentString = "\r\n";
        Format += BytesPerFormatCharacter;
        FormatCharacter = ((*Format & 0xff) | (*(Format + 1) << 8)) & FormatMask;
        if (FormatCharacter != '\r') {
          Format   -= BytesPerFormatCharacter;
        }
        break;

      case '%':
      default:
        //
        // if the type is '%' or unknown, then print it to the screen
        //
        ArgumentString = (CHAR8 *)&FormatCharacter;
        Flags |= ARGUMENT_UNICODE;
        break;
      }
      break;
 
    case '\r':
      Format += BytesPerFormatCharacter;
      FormatCharacter = ((*Format & 0xff) | (*(Format + 1) << 8)) & FormatMask;
      if (FormatCharacter == '\n') {
        //
        // Translate '\r\n' to '\r\n'
        //
        ArgumentString = "\r\n";
      } else {
        //
        // Translate '\r' to '\r'
        //
        ArgumentString = "\r";
        Format   -= BytesPerFormatCharacter;
      }
      break;

    case '\n':
      //
      // Translate '\n' to '\r\n' and '\n\r' to '\r\n'
      //
      ArgumentString = "\r\n";
      Format += BytesPerFormatCharacter;
      FormatCharacter = ((*Format & 0xff) | (*(Format + 1) << 8)) & FormatMask;
      if (FormatCharacter != '\r') {
        Format   -= BytesPerFormatCharacter;
      }
      break;

    default:
      ArgumentString = (CHAR8 *)&FormatCharacter;
      Flags |= ARGUMENT_UNICODE;
      break;
    }

    //
    // Retrieve the ArgumentString attriubutes
    //
    if ((Flags & ARGUMENT_UNICODE) != 0) {
      ArgumentMask = 0xffff;
      BytesPerArgumentCharacter = 2;
    } else {
      ArgumentMask = 0xff;
      BytesPerArgumentCharacter = 1;
    }
    if ((Flags & ARGUMENT_REVERSED) != 0) {
      BytesPerArgumentCharacter = -BytesPerArgumentCharacter;
    } else {
      //
      // Compute the number of characters in ArgumentString and store it in Count
      // ArgumentString is either null-terminated, or it contains Precision characters
      //
      for (Count = 0; Count < Precision || ((Flags & PRECISION) == 0); Count++) {
        ArgumentCharacter = ((ArgumentString[Count * BytesPerArgumentCharacter] & 0xff) | ((ArgumentString[Count * BytesPerArgumentCharacter + 1]) << 8)) & ArgumentMask;
        if (ArgumentCharacter == 0) {
          break;
        }
      }
    }

    if (Precision < Count) {
      Precision = Count;
    }

    //
    // Pad before the string
    //
    if ((Flags & (PAD_TO_WIDTH | LEFT_JUSTIFY)) == (PAD_TO_WIDTH)) {
      LengthToReturn += ((Width - Precision) * BytesPerOutputCharacter);
      if ((Flags & COUNT_ONLY_NO_PRINT) == 0 && Buffer != NULL) {
        Buffer = InternalPrintLibFillBuffer (Buffer, EndBuffer, Width - Precision, ' ', BytesPerOutputCharacter);
      }
    }

    if (ZeroPad) {
      if (Prefix != 0) {
        LengthToReturn += (1 * BytesPerOutputCharacter);
        if ((Flags & COUNT_ONLY_NO_PRINT) == 0 && Buffer != NULL) {
          Buffer = InternalPrintLibFillBuffer (Buffer, EndBuffer, 1, Prefix, BytesPerOutputCharacter);
        }
      }
      LengthToReturn += ((Precision - Count) * BytesPerOutputCharacter);
      if ((Flags & COUNT_ONLY_NO_PRINT) == 0 && Buffer != NULL) {
        Buffer = InternalPrintLibFillBuffer (Buffer, EndBuffer, Precision - Count, '0', BytesPerOutputCharacter);
      }
    } else {
      LengthToReturn += ((Precision - Count) * BytesPerOutputCharacter);
      if ((Flags & COUNT_ONLY_NO_PRINT) == 0 && Buffer != NULL) {
        Buffer = InternalPrintLibFillBuffer (Buffer, EndBuffer, Precision - Count, ' ', BytesPerOutputCharacter);
      }
      if (Prefix != 0) {
        LengthToReturn += (1 * BytesPerOutputCharacter);
        if ((Flags & COUNT_ONLY_NO_PRINT) == 0 && Buffer != NULL) {
          Buffer = InternalPrintLibFillBuffer (Buffer, EndBuffer, 1, Prefix, BytesPerOutputCharacter);
        }
      }
    }

    //
    // Output the Prefix character if it is present
    //
    Index = 0;
    if (Prefix != 0) {
      Index++;
    }

    //
    // Copy the string into the output buffer performing the required type conversions
    //
    while (Index < Count) {
      ArgumentCharacter = ((*ArgumentString & 0xff) | (*(ArgumentString + 1) << 8)) & ArgumentMask;

      LengthToReturn += (1 * BytesPerOutputCharacter);
      if ((Flags & COUNT_ONLY_NO_PRINT) == 0 && Buffer != NULL) {
        Buffer = InternalPrintLibFillBuffer (Buffer, EndBuffer, 1, ArgumentCharacter, BytesPerOutputCharacter);
      }
      ArgumentString    += BytesPerArgumentCharacter;
      Index++;
      if (Comma) {
        Digits++;
        if (Digits == 3) {
          Digits = 0;
          Index++;
          if (Index < Count) {
            LengthToReturn += (1 * BytesPerOutputCharacter);
            if ((Flags & COUNT_ONLY_NO_PRINT) == 0 && Buffer != NULL) {
              Buffer = InternalPrintLibFillBuffer (Buffer, EndBuffer, 1, ',', BytesPerOutputCharacter);
            }
          }
        }
      }
    }

    //
    // Pad after the string
    //
    if ((Flags & (PAD_TO_WIDTH | LEFT_JUSTIFY)) == (PAD_TO_WIDTH | LEFT_JUSTIFY)) {
      LengthToReturn += ((Width - Precision) * BytesPerOutputCharacter);
      if ((Flags & COUNT_ONLY_NO_PRINT) == 0 && Buffer != NULL) {
        Buffer = InternalPrintLibFillBuffer (Buffer, EndBuffer, Width - Precision, ' ', BytesPerOutputCharacter);
      }
    }

    //
    // Get the next character from the format string
    //
    Format += BytesPerFormatCharacter;

    //
    // Get the next character from the format string
    //
    FormatCharacter = ((*Format & 0xff) | (*(Format + 1) << 8)) & FormatMask;
  }

  if ((Flags & COUNT_ONLY_NO_PRINT) != 0) {
    return (LengthToReturn / BytesPerOutputCharacter);
  }

  ASSERT (Buffer != NULL);
  //
  // Null terminate the Unicode or ASCII string
  //
  InternalPrintLibFillBuffer (Buffer, EndBuffer + BytesPerOutputCharacter, 1, 0, BytesPerOutputCharacter);
  //
  // Make sure output buffer cannot contain more than PcdMaximumUnicodeStringLength
  // Unicode characters if PcdMaximumUnicodeStringLength is not zero. 
  //
  ASSERT ((((Flags & OUTPUT_UNICODE) == 0)) || (StrSize ((CHAR16 *) OriginalBuffer) != 0));
  //
  // Make sure output buffer cannot contain more than PcdMaximumAsciiStringLength
  // ASCII characters if PcdMaximumAsciiStringLength is not zero. 
  //
  ASSERT ((((Flags & OUTPUT_UNICODE) != 0)) || (AsciiStrSize (OriginalBuffer) != 0));

  return ((Buffer - OriginalBuffer) / BytesPerOutputCharacter);
}

/**
  Returns the number of characters that would be produced by if the formatted 
  output were produced not including the Null-terminator.

  If FormatString is NULL, then ASSERT().
  If FormatString is not aligned on a 16-bit boundary, then ASSERT().

  @param[in]  FormatString    A Null-terminated Unicode format string.
  @param[in]  Marker          VA_LIST marker for the variable argument list.

  @return The number of characters that would be produced, not including the 
          Null-terminator.
**/
UINTN
EFIAPI
SPrintLength (
  IN  CONST CHAR16   *FormatString,
  IN  VA_LIST       Marker
  )
{
  ASSERT(FormatString != NULL);
  return InternalPrintLibSPrintMarker (NULL, 0, FORMAT_UNICODE | OUTPUT_UNICODE | COUNT_ONLY_NO_PRINT, (CHAR8 *)FormatString, Marker, NULL);
}

/**
  Returns the number of characters that would be produced by if the formatted 
  output were produced not including the Null-terminator.

  If FormatString is NULL, then ASSERT().

  @param[in]  FormatString    A Null-terminated ASCII format string.
  @param[in]  Marker          VA_LIST marker for the variable argument list.

  @return The number of characters that would be produced, not including the 
          Null-terminator.
**/
UINTN
EFIAPI
SPrintLengthAsciiFormat (
  IN  CONST CHAR8   *FormatString,
  IN  VA_LIST       Marker
  )
{
  ASSERT(FormatString != NULL);
  return InternalPrintLibSPrintMarker (NULL, 0, OUTPUT_UNICODE | COUNT_ONLY_NO_PRINT, (CHAR8 *)FormatString, Marker, NULL);
}