/** @file
  This library provides helper functions to prevent integer overflow during
  type conversion, addition, subtraction, and multiplication.

  Copyright (c) 2017, Microsoft Corporation

  All rights reserved.
  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are met:
  1. Redistributions of source code must retain the above copyright notice,
  this list of conditions and the following disclaimer.
  2. Redistributions in binary form must reproduce the above copyright notice,
  this list of conditions and the following disclaimer in the documentation
  and/or other materials provided with the distribution.

  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
  OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

**/

#include <Base.h>
#include <Library/SafeIntLib.h>
#include <Library/BaseLib.h>


//
// Magnitude of MIN_INT64 as expressed by a UINT64 number.
//
#define MIN_INT64_MAGNITUDE (((UINT64)(- (MIN_INT64 + 1))) + 1)

//
// Conversion functions
//
// There are three reasons for having conversion functions:
//
// 1. We are converting from a signed type to an unsigned type of the same
//    size, or vice-versa.
//
// 2. We are converting to a smaller type, and we could therefore possibly
//    overflow.
//
// 3. We are converting to a bigger type, and we are signed and the type we are
//    converting to is unsigned.
//

/**
  INT8 -> UINT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt8ToUint8 (
  IN  INT8   Operand,
  OUT UINT8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT8 -> CHAR8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to CHAR8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt8ToChar8 (
  IN  INT8   Operand,
  OUT CHAR8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (CHAR8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = CHAR8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT8 -> UINT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt8ToUint16 (
  IN  INT8    Operand,
  OUT UINT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT8 -> UINT32 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt8ToUint32 (
  IN  INT8    Operand,
  OUT UINT32  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINT32)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT32_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT8 -> UINTN conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt8ToUintn (
  IN  INT8   Operand,
  OUT UINTN  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINTN)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINTN_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT8 -> UINT64 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT64_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt8ToUint64 (
  IN  INT8    Operand,
  OUT UINT64  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINT64)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT64_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT8 -> INT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint8ToInt8 (
  IN  UINT8  Operand,
  OUT INT8   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT8) {
    *Result = (INT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT8 -> CHAR8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to CHAR8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint8ToChar8 (
  IN  UINT8  Operand,
  OUT CHAR8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT8) {
    *Result = (CHAR8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = CHAR8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT16 -> INT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt16ToInt8 (
  IN  INT16  Operand,
  OUT INT8   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= MIN_INT8) && (Operand <= MAX_INT8)) {
    *Result = (INT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT16 -> CHAR8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to CHAR8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt16ToChar8 (
  IN  INT16  Operand,
  OUT CHAR8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= 0) && (Operand <= MAX_INT8)) {
    *Result = (CHAR8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = CHAR8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT16 -> UINT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt16ToUint8 (
  IN  INT16  Operand,
  OUT UINT8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= 0) && (Operand <= MAX_UINT8)) {
    *Result = (UINT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT16 -> UINT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt16ToUint16 (
  IN  INT16   Operand,
  OUT UINT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT16 -> UINT32 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt16ToUint32 (
  IN  INT16   Operand,
  OUT UINT32  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINT32)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT32_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT16 -> UINTN conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt16ToUintn (
  IN  INT16  Operand,
  OUT UINTN  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINTN)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINTN_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT16 -> UINT64 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT64_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt16ToUint64 (
  IN  INT16   Operand,
  OUT UINT64  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINT64)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT64_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT16 -> INT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint16ToInt8 (
  IN  UINT16  Operand,
  OUT INT8    *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT8) {
    *Result = (INT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT16 -> CHAR8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to CHAR8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint16ToChar8 (
  IN  UINT16  Operand,
  OUT CHAR8   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT8) {
    *Result = (INT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = CHAR8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT16 -> UINT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint16ToUint8 (
  IN  UINT16  Operand,
  OUT UINT8   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_UINT8) {
    *Result = (UINT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT16 -> INT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint16ToInt16 (
  IN  UINT16  Operand,
  OUT INT16   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT16) {
    *Result = (INT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT32 -> INT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt32ToInt8 (
  IN  INT32  Operand,
  OUT INT8   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= MIN_INT8) && (Operand <= MAX_INT8)) {
    *Result = (INT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT32 -> CHAR8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to CHAR8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt32ToChar8 (
  IN  INT32  Operand,
  OUT CHAR8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= 0) && (Operand <= MAX_INT8)) {
    *Result = (CHAR8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = CHAR8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT32 -> UINT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt32ToUint8 (
  IN  INT32  Operand,
  OUT UINT8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= 0) && (Operand <= MAX_UINT8)) {
    *Result = (UINT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT32 -> INT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt32ToInt16 (
  IN  INT32  Operand,
  OUT INT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= MIN_INT16) && (Operand <= MAX_INT16)) {
    *Result = (INT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT32 -> UINT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt32ToUint16 (
  IN  INT32   Operand,
  OUT UINT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= 0) && (Operand <= MAX_UINT16)) {
    *Result = (UINT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT32 -> UINT32 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt32ToUint32 (
  IN  INT32   Operand,
  OUT UINT32  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINT32)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT32_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT32 -> UINT64 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT64_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt32ToUint64 (
  IN  INT32   Operand,
  OUT UINT64  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINT64)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT64_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT32 -> INT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint32ToInt8 (
  IN  UINT32  Operand,
  OUT INT8    *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT8) {
    *Result = (INT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT32 -> CHAR8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to CHAR8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint32ToChar8 (
  IN  UINT32  Operand,
  OUT CHAR8   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT8) {
    *Result = (INT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = CHAR8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT32 -> UINT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint32ToUint8 (
  IN  UINT32  Operand,
  OUT UINT8   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_UINT8) {
    *Result = (UINT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT32 -> INT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint32ToInt16 (
  IN  UINT32  Operand,
  OUT INT16   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT16) {
    *Result = (INT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT32 -> UINT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint32ToUint16 (
  IN  UINT32  Operand,
  OUT UINT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_UINT16) {
    *Result = (UINT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT32 -> INT32 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint32ToInt32 (
  IN  UINT32  Operand,
  OUT INT32   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT32) {
    *Result = (INT32)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT32_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INTN -> INT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeIntnToInt8 (
  IN  INTN  Operand,
  OUT INT8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= MIN_INT8) && (Operand <= MAX_INT8)) {
    *Result = (INT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INTN -> CHAR8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to CHAR8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeIntnToChar8 (
  IN  INTN   Operand,
  OUT CHAR8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= 0) && (Operand <= MAX_INT8)) {
    *Result = (CHAR8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = CHAR8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INTN -> UINT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeIntnToUint8 (
  IN  INTN   Operand,
  OUT UINT8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= 0) && (Operand <= MAX_UINT8)) {
    *Result = (UINT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INTN -> INT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeIntnToInt16 (
  IN  INTN   Operand,
  OUT INT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= MIN_INT16) && (Operand <= MAX_INT16)) {
    *Result = (INT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INTN -> UINT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeIntnToUint16 (
  IN  INTN    Operand,
  OUT UINT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= 0) && (Operand <= MAX_UINT16)) {
    *Result = (UINT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INTN -> UINTN conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeIntnToUintn (
  IN  INTN   Operand,
  OUT UINTN  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINTN)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINTN_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INTN -> UINT64 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT64_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeIntnToUint64 (
  IN  INTN    Operand,
  OUT UINT64  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINT64)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT64_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINTN -> INT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUintnToInt8 (
  IN  UINTN  Operand,
  OUT INT8   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT8) {
    *Result = (INT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINTN -> CHAR8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to CHAR8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUintnToChar8 (
  IN  UINTN  Operand,
  OUT CHAR8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT8) {
    *Result = (INT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = CHAR8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINTN -> UINT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUintnToUint8 (
  IN  UINTN  Operand,
  OUT UINT8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_UINT8) {
    *Result = (UINT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINTN -> INT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUintnToInt16 (
  IN  UINTN  Operand,
  OUT INT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT16) {
    *Result = (INT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINTN -> UINT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUintnToUint16 (
  IN  UINTN   Operand,
  OUT UINT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_UINT16) {
    *Result = (UINT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINTN -> INT32 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUintnToInt32 (
  IN  UINTN  Operand,
  OUT INT32  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT32) {
    *Result = (INT32)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT32_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINTN -> INTN conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUintnToIntn (
  IN  UINTN  Operand,
  OUT INTN   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INTN) {
    *Result = (INTN)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INTN_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT64 -> INT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt64ToInt8 (
  IN  INT64  Operand,
  OUT INT8   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= MIN_INT8) && (Operand <= MAX_INT8)) {
    *Result = (INT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT64 -> CHAR8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to CHAR8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt64ToChar8 (
  IN  INT64  Operand,
  OUT CHAR8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= 0) && (Operand <= MAX_INT8)) {
    *Result = (CHAR8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = CHAR8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT64 -> UINT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt64ToUint8 (
  IN  INT64  Operand,
  OUT UINT8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= 0) && (Operand <= MAX_UINT8)) {
    *Result = (UINT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT64 -> INT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt64ToInt16 (
  IN  INT64  Operand,
  OUT INT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= MIN_INT16) && (Operand <= MAX_INT16)) {
    *Result = (INT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT64 -> UINT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt64ToUint16 (
  IN  INT64   Operand,
  OUT UINT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= 0) && (Operand <= MAX_UINT16)) {
    *Result = (UINT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT64 -> INT32 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt64ToInt32 (
  IN  INT64  Operand,
  OUT INT32  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= MIN_INT32) && (Operand <= MAX_INT32)) {
    *Result = (INT32)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT32_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT64 -> UINT32 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt64ToUint32 (
  IN  INT64   Operand,
  OUT UINT32  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Operand >= 0) && (Operand <= MAX_UINT32)) {
    *Result = (UINT32)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT32_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  INT64 -> UINT64 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT64_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt64ToUint64 (
  IN  INT64   Operand,
  OUT UINT64  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand >= 0) {
    *Result = (UINT64)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT64_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT64 -> INT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint64ToInt8 (
  IN  UINT64  Operand,
  OUT INT8    *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT8) {
    *Result = (INT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT64 -> CHAR8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to CHAR8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint64ToChar8 (
  IN  UINT64  Operand,
  OUT CHAR8   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT8) {
    *Result = (INT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = CHAR8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT64 -> UINT8 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint64ToUint8 (
  IN  UINT64  Operand,
  OUT UINT8   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_UINT8) {
    *Result = (UINT8)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT64 -> INT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint64ToInt16 (
  IN  UINT64  Operand,
  OUT INT16   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT16) {
    *Result = (INT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT64 -> UINT16 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint64ToUint16 (
  IN  UINT64  Operand,
  OUT UINT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_UINT16) {
    *Result = (UINT16)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT64 -> INT32 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint64ToInt32 (
  IN  UINT64  Operand,
  OUT INT32   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT32) {
    *Result = (INT32)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT32_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT64 -> UINT32 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to UINT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint64ToUint32 (
  IN  UINT64  Operand,
  OUT UINT32  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_UINT32) {
    *Result = (UINT32)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT32_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT64 -> INTN conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint64ToIntn (
  IN  UINT64  Operand,
  OUT INTN    *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INTN) {
    *Result = (INTN)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INTN_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT64 -> INT64 conversion

  Converts the value specified by Operand to a value specified by Result type
  and stores the converted value into the caller allocated output buffer
  specified by Result.  The caller must pass in a Result buffer that is at
  least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the conversion results in an overflow or an underflow condition, then
  Result is set to INT64_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Operand  Operand to be converted to new type
  @param[out]  Result   Pointer to the result of conversion

  @retval  RETURN_SUCCESS            Successful conversion
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint64ToInt64 (
  IN  UINT64  Operand,
  OUT INT64   *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Operand <= MAX_INT64) {
    *Result = (INT64)Operand;
    Status = RETURN_SUCCESS;
  } else {
    *Result = INT64_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

//
// Addition functions
//

/**
  UINT8 addition

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to UINT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Augend  A number to which addend will be added
  @param[in]   Addend  A number to be added to another
  @param[out]  Result  Pointer to the result of addition

  @retval  RETURN_SUCCESS            Successful addition
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint8Add (
  IN  UINT8  Augend,
  IN  UINT8  Addend,
  OUT UINT8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (((UINT8)(Augend + Addend)) >= Augend) {
    *Result = (UINT8)(Augend + Addend);
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT16 addition

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to UINT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Augend  A number to which addend will be added
  @param[in]   Addend  A number to be added to another
  @param[out]  Result  Pointer to the result of addition

  @retval  RETURN_SUCCESS            Successful addition
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint16Add (
  IN  UINT16  Augend,
  IN  UINT16  Addend,
  OUT UINT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (((UINT16)(Augend + Addend)) >= Augend) {
    *Result = (UINT16)(Augend + Addend);
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT32 addition

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to UINT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Augend  A number to which addend will be added
  @param[in]   Addend  A number to be added to another
  @param[out]  Result  Pointer to the result of addition

  @retval  RETURN_SUCCESS            Successful addition
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint32Add (
  IN  UINT32  Augend,
  IN  UINT32  Addend,
  OUT UINT32  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Augend + Addend) >= Augend) {
    *Result = (Augend + Addend);
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT32_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT64 addition

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to UINT64_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Augend  A number to which addend will be added
  @param[in]   Addend  A number to be added to another
  @param[out]  Result  Pointer to the result of addition

  @retval  RETURN_SUCCESS            Successful addition
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint64Add (
  IN  UINT64  Augend,
  IN  UINT64  Addend,
  OUT UINT64  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if ((Augend + Addend) >= Augend) {
    *Result = (Augend + Addend);
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT64_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

//
// Subtraction functions
//

/**
  UINT8 subtraction

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to UINT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Minuend     A number from which another is to be subtracted.
  @param[in]   Subtrahend  A number to be subtracted from another
  @param[out]  Result      Pointer to the result of subtraction

  @retval  RETURN_SUCCESS            Successful subtraction
  @retval  RETURN_BUFFER_TOO_SMALL   Underflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint8Sub (
  IN  UINT8  Minuend,
  IN  UINT8  Subtrahend,
  OUT UINT8  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Minuend >= Subtrahend) {
    *Result = (UINT8)(Minuend - Subtrahend);
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT8_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT16 subtraction

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to UINT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Minuend     A number from which another is to be subtracted.
  @param[in]   Subtrahend  A number to be subtracted from another
  @param[out]  Result      Pointer to the result of subtraction

  @retval  RETURN_SUCCESS            Successful subtraction
  @retval  RETURN_BUFFER_TOO_SMALL   Underflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint16Sub (
  IN  UINT16  Minuend,
  IN  UINT16  Subtrahend,
  OUT UINT16  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Minuend >= Subtrahend) {
    *Result = (UINT16)(Minuend - Subtrahend);
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT16_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT32 subtraction

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to UINT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Minuend     A number from which another is to be subtracted.
  @param[in]   Subtrahend  A number to be subtracted from another
  @param[out]  Result      Pointer to the result of subtraction

  @retval  RETURN_SUCCESS            Successful subtraction
  @retval  RETURN_BUFFER_TOO_SMALL   Underflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint32Sub (
  IN  UINT32  Minuend,
  IN  UINT32  Subtrahend,
  OUT UINT32  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Minuend >= Subtrahend) {
    *Result = (Minuend - Subtrahend);
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT32_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

/**
  UINT64 subtraction

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to UINT64_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Minuend     A number from which another is to be subtracted.
  @param[in]   Subtrahend  A number to be subtracted from another
  @param[out]  Result      Pointer to the result of subtraction

  @retval  RETURN_SUCCESS            Successful subtraction
  @retval  RETURN_BUFFER_TOO_SMALL   Underflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint64Sub (
  IN  UINT64  Minuend,
  IN  UINT64  Subtrahend,
  OUT UINT64  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  if (Minuend >= Subtrahend) {
    *Result = (Minuend - Subtrahend);
    Status = RETURN_SUCCESS;
  } else {
    *Result = UINT64_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  }

  return Status;
}

//
// Multiplication functions
//

/**
  UINT8 multiplication

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to UINT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Multiplicand  A number that is to be multiplied by another
  @param[in]   Multiplier    A number by which the multiplicand is to be multiplied
  @param[out]  Result        Pointer to the result of multiplication

  @retval  RETURN_SUCCESS            Successful multiplication
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint8Mult (
  IN  UINT8  Multiplicand,
  IN  UINT8  Multiplier,
  OUT UINT8  *Result
  )
{
  UINT32  IntermediateResult;

  IntermediateResult = ((UINT32)Multiplicand) *((UINT32)Multiplier);

  return SafeUint32ToUint8 (IntermediateResult, Result);
}

/**
  UINT16 multiplication

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to UINT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Multiplicand  A number that is to be multiplied by another
  @param[in]   Multiplier    A number by which the multiplicand is to be multiplied
  @param[out]  Result        Pointer to the result of multiplication

  @retval  RETURN_SUCCESS            Successful multiplication
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint16Mult (
  IN  UINT16  Multiplicand,
  IN  UINT16  Multiplier,
  OUT UINT16  *Result
  )
{
  UINT32  IntermediateResult;

  IntermediateResult = ((UINT32)Multiplicand) *((UINT32)Multiplier);

  return SafeUint32ToUint16 (IntermediateResult, Result);
}

/**
  UINT32 multiplication

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to UINT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Multiplicand  A number that is to be multiplied by another
  @param[in]   Multiplier    A number by which the multiplicand is to be multiplied
  @param[out]  Result        Pointer to the result of multiplication

  @retval  RETURN_SUCCESS            Successful multiplication
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint32Mult (
  IN  UINT32  Multiplicand,
  IN  UINT32  Multiplier,
  OUT UINT32  *Result
  )
{
  UINT64  IntermediateResult;

  IntermediateResult = ((UINT64) Multiplicand) *((UINT64) Multiplier);

  return SafeUint64ToUint32 (IntermediateResult, Result);
}

/**
  UINT64 multiplication

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to UINT64_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Multiplicand  A number that is to be multiplied by another
  @param[in]   Multiplier    A number by which the multiplicand is to be multiplied
  @param[out]  Result        Pointer to the result of multiplication

  @retval  RETURN_SUCCESS            Successful multiplication
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeUint64Mult (
  IN  UINT64  Multiplicand,
  IN  UINT64  Multiplier,
  OUT UINT64  *Result
  )
{
  RETURN_STATUS  Status;
  UINT32         DwordA;
  UINT32         DwordB;
  UINT32         DwordC;
  UINT32         DwordD;
  UINT64         ProductAD;
  UINT64         ProductBC;
  UINT64         ProductBD;
  UINT64         UnsignedResult;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  ProductAD = 0;
  ProductBC = 0;
  ProductBD = 0;
  UnsignedResult = 0;
  Status = RETURN_BUFFER_TOO_SMALL;

  //
  // 64x64 into 128 is like 32.32 x 32.32.
  //
  // a.b * c.d = a*(c.d) + .b*(c.d) = a*c + a*.d + .b*c + .b*.d
  // back in non-decimal notation where A=a*2^32 and C=c*2^32:
  // A*C + A*d + b*C + b*d
  // So there are four components to add together.
  //   result = (a*c*2^64) + (a*d*2^32) + (b*c*2^32) + (b*d)
  //
  // a * c must be 0 or there would be bits in the high 64-bits
  // a * d must be less than 2^32 or there would be bits in the high 64-bits
  // b * c must be less than 2^32 or there would be bits in the high 64-bits
  // then there must be no overflow of the resulting values summed up.
  //
  DwordA = (UINT32)RShiftU64 (Multiplicand, 32);
  DwordC = (UINT32)RShiftU64 (Multiplier, 32);

  //
  // common case -- if high dwords are both zero, no chance for overflow
  //
  if ((DwordA == 0) && (DwordC == 0)) {
    DwordB = (UINT32)Multiplicand;
    DwordD = (UINT32)Multiplier;

    *Result = (((UINT64)DwordB) *(UINT64)DwordD);
    Status = RETURN_SUCCESS;
  } else {
    //
    // a * c must be 0 or there would be bits set in the high 64-bits
    //
    if ((DwordA == 0) ||
        (DwordC == 0)) {
      DwordD = (UINT32)Multiplier;

      //
      // a * d must be less than 2^32 or there would be bits set in the high 64-bits
      //
      ProductAD = (((UINT64)DwordA) *(UINT64)DwordD);
      if ((ProductAD & 0xffffffff00000000) == 0) {
        DwordB = (UINT32)Multiplicand;

        //
        // b * c must be less than 2^32 or there would be bits set in the high 64-bits
        //
        ProductBC = (((UINT64)DwordB) *(UINT64)DwordC);
        if ((ProductBC & 0xffffffff00000000) == 0) {
          //
          // now sum them all up checking for overflow.
          // shifting is safe because we already checked for overflow above
          //
          if (!RETURN_ERROR (SafeUint64Add (LShiftU64 (ProductBC, 32), LShiftU64 (ProductAD, 32), &UnsignedResult))) {
            //
            // b * d
            //
            ProductBD = (((UINT64)DwordB) *(UINT64)DwordD);

            if (!RETURN_ERROR (SafeUint64Add (UnsignedResult, ProductBD, &UnsignedResult))) {
              *Result = UnsignedResult;
              Status = RETURN_SUCCESS;
            }
          }
        }
      }
    }
  }

  if (RETURN_ERROR (Status)) {
    *Result = UINT64_ERROR;
  }
  return Status;
}

//
// Signed operations
//
// Strongly consider using unsigned numbers.
//
// Signed numbers are often used where unsigned numbers should be used.
// For example file sizes and array indices should always be unsigned.
// Subtracting a larger positive signed number from a smaller positive
// signed number with SafeInt32Sub will succeed, producing a negative number,
// that then must not be used as an array index (but can occasionally be
// used as a pointer index.) Similarly for adding a larger magnitude
// negative number to a smaller magnitude positive number.
//
// This library does not protect you from such errors. It tells you if your
// integer operations overflowed, not if you are doing the right thing
// with your non-overflowed integers.
//
// Likewise you can overflow a buffer with a non-overflowed unsigned index.
//

//
// Signed addition functions
//

/**
  INT8 Addition

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to INT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Augend  A number to which addend will be added
  @param[in]   Addend  A number to be added to another
  @param[out]  Result  Pointer to the result of addition

  @retval  RETURN_SUCCESS            Successful addition
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt8Add (
  IN  INT8  Augend,
  IN  INT8  Addend,
  OUT INT8  *Result
  )
{
  return SafeInt32ToInt8 (((INT32)Augend) + ((INT32)Addend), Result);
}

/**
  CHAR8 Addition

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to CHAR8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Augend  A number to which addend will be added
  @param[in]   Addend  A number to be added to another
  @param[out]  Result  Pointer to the result of addition

  @retval  RETURN_SUCCESS            Successful addition
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeChar8Add (
  IN  CHAR8  Augend,
  IN  CHAR8  Addend,
  OUT CHAR8  *Result
  )
{
  INT32  Augend32;
  INT32  Addend32;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  Augend32 = (INT32)Augend;
  Addend32 = (INT32)Addend;
  if (Augend32 < 0 || Augend32 > MAX_INT8) {
    *Result = CHAR8_ERROR;
    return RETURN_BUFFER_TOO_SMALL;
  }
  if (Addend32 < 0 || Addend32 > MAX_INT8) {
    *Result = CHAR8_ERROR;
    return RETURN_BUFFER_TOO_SMALL;
  }

  return SafeInt32ToChar8 (Augend32 + Addend32, Result);
}

/**
  INT16 Addition

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to INT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Augend  A number to which addend will be added
  @param[in]   Addend  A number to be added to another
  @param[out]  Result  Pointer to the result of addition

  @retval  RETURN_SUCCESS            Successful addition
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt16Add (
  IN  INT16  Augend,
  IN  INT16  Addend,
  OUT INT16  *Result
  )
{
  return SafeInt32ToInt16 (((INT32)Augend) + ((INT32)Addend), Result);
}

/**
  INT32 Addition

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to INT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Augend  A number to which addend will be added
  @param[in]   Addend  A number to be added to another
  @param[out]  Result  Pointer to the result of addition

  @retval  RETURN_SUCCESS            Successful addition
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt32Add (
  IN  INT32  Augend,
  IN  INT32  Addend,
  OUT INT32  *Result
  )
{
  return SafeInt64ToInt32 (((INT64)Augend) + ((INT64)Addend), Result);
}

/**
  INT64 Addition

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to INT64_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Augend  A number to which addend will be added
  @param[in]   Addend  A number to be added to another
  @param[out]  Result  Pointer to the result of addition

  @retval  RETURN_SUCCESS            Successful addition
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt64Add (
  IN  INT64  Augend,
  IN  INT64  Addend,
  OUT INT64  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  //
  // * An Addend of zero can never cause underflow or overflow.
  //
  // * A positive Addend can only cause overflow. The overflow condition is
  //
  //     (Augend + Addend) > MAX_INT64
  //
  //   Subtracting Addend from both sides yields
  //
  //     Augend > (MAX_INT64 - Addend)
  //
  //   This condition can be coded directly in C because the RHS will neither
  //   underflow nor overflow. That is due to the starting condition:
  //
  //     0 < Addend <= MAX_INT64
  //
  //   Multiplying all three sides by (-1) yields
  //
  //     0 > (-Addend) >= (-MAX_INT64)
  //
  //   Adding MAX_INT64 to all three sides yields
  //
  //     MAX_INT64 > (MAX_INT64 - Addend) >= 0
  //
  // * A negative Addend can only cause underflow. The underflow condition is
  //
  //     (Augend + Addend) < MIN_INT64
  //
  //   Subtracting Addend from both sides yields
  //
  //     Augend < (MIN_INT64 - Addend)
  //
  //   This condition can be coded directly in C because the RHS will neither
  //   underflow nor overflow. That is due to the starting condition:
  //
  //     MIN_INT64 <= Addend < 0
  //
  //   Multiplying all three sides by (-1) yields
  //
  //     (-MIN_INT64) >= (-Addend) > 0
  //
  //   Adding MIN_INT64 to all three sides yields
  //
  //     0 >= (MIN_INT64 - Addend) > MIN_INT64
  //
  if (((Addend > 0) && (Augend > (MAX_INT64 - Addend))) ||
      ((Addend < 0) && (Augend < (MIN_INT64 - Addend)))) {
    *Result = INT64_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  } else {
    *Result = Augend + Addend;
    Status = RETURN_SUCCESS;
  }

  return Status;
}

//
// Signed subtraction functions
//

/**
  INT8 Subtraction

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to INT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Minuend     A number from which another is to be subtracted.
  @param[in]   Subtrahend  A number to be subtracted from another
  @param[out]  Result      Pointer to the result of subtraction

  @retval  RETURN_SUCCESS            Successful subtraction
  @retval  RETURN_BUFFER_TOO_SMALL   Underflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt8Sub (
  IN  INT8  Minuend,
  IN  INT8  Subtrahend,
  OUT INT8  *Result
  )
{
  return SafeInt32ToInt8 (((INT32)Minuend) - ((INT32)Subtrahend), Result);
}

/**
  CHAR8 Subtraction

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to CHAR8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Minuend     A number from which another is to be subtracted.
  @param[in]   Subtrahend  A number to be subtracted from another
  @param[out]  Result      Pointer to the result of subtraction

  @retval  RETURN_SUCCESS            Successful subtraction
  @retval  RETURN_BUFFER_TOO_SMALL   Underflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeChar8Sub (
  IN  CHAR8  Minuend,
  IN  CHAR8  Subtrahend,
  OUT CHAR8  *Result
  )
{
  INT32  Minuend32;
  INT32  Subtrahend32;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  Minuend32    = (INT32)Minuend;
  Subtrahend32 = (INT32)Subtrahend;
  if (Minuend32 < 0 || Minuend32 > MAX_INT8) {
    *Result = CHAR8_ERROR;
    return RETURN_BUFFER_TOO_SMALL;
  }
  if (Subtrahend32 < 0 || Subtrahend32 > MAX_INT8) {
    *Result = CHAR8_ERROR;
    return RETURN_BUFFER_TOO_SMALL;
  }

  return SafeInt32ToChar8 (Minuend32 - Subtrahend32, Result);
}

/**
  INT16 Subtraction

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to INT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Minuend     A number from which another is to be subtracted.
  @param[in]   Subtrahend  A number to be subtracted from another
  @param[out]  Result      Pointer to the result of subtraction

  @retval  RETURN_SUCCESS            Successful subtraction
  @retval  RETURN_BUFFER_TOO_SMALL   Underflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt16Sub (
  IN  INT16  Minuend,
  IN  INT16  Subtrahend,
  OUT INT16  *Result
  )
{
  return SafeInt32ToInt16 (((INT32)Minuend) - ((INT32)Subtrahend), Result);
}

/**
  INT32 Subtraction

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to INT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Minuend     A number from which another is to be subtracted.
  @param[in]   Subtrahend  A number to be subtracted from another
  @param[out]  Result      Pointer to the result of subtraction

  @retval  RETURN_SUCCESS            Successful subtraction
  @retval  RETURN_BUFFER_TOO_SMALL   Underflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt32Sub (
  IN  INT32  Minuend,
  IN  INT32  Subtrahend,
  OUT INT32  *Result
  )
{
  return SafeInt64ToInt32 (((INT64)Minuend) - ((INT64)Subtrahend), Result);
}

/**
  INT64 Subtraction

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to INT64_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Minuend     A number from which another is to be subtracted.
  @param[in]   Subtrahend  A number to be subtracted from another
  @param[out]  Result      Pointer to the result of subtraction

  @retval  RETURN_SUCCESS            Successful subtraction
  @retval  RETURN_BUFFER_TOO_SMALL   Underflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt64Sub (
  IN  INT64  Minuend,
  IN  INT64  Subtrahend,
  OUT INT64  *Result
  )
{
  RETURN_STATUS  Status;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  //
  // * A Subtrahend of zero can never cause underflow or overflow.
  //
  // * A positive Subtrahend can only cause underflow. The underflow condition
  //   is:
  //
  //     (Minuend - Subtrahend) < MIN_INT64
  //
  //   Adding Subtrahend to both sides yields
  //
  //     Minuend < (MIN_INT64 + Subtrahend)
  //
  //   This condition can be coded directly in C because the RHS will neither
  //   underflow nor overflow. That is due to the starting condition:
  //
  //     0 < Subtrahend <= MAX_INT64
  //
  //   Adding MIN_INT64 to all three sides yields
  //
  //     MIN_INT64 < (MIN_INT64 + Subtrahend) <= (MIN_INT64 + MAX_INT64) = -1
  //
  // * A negative Subtrahend can only cause overflow. The overflow condition is
  //
  //     (Minuend - Subtrahend) > MAX_INT64
  //
  //   Adding Subtrahend to both sides yields
  //
  //     Minuend > (MAX_INT64 + Subtrahend)
  //
  //   This condition can be coded directly in C because the RHS will neither
  //   underflow nor overflow. That is due to the starting condition:
  //
  //     MIN_INT64 <= Subtrahend < 0
  //
  //   Adding MAX_INT64 to all three sides yields
  //
  //     -1 = (MAX_INT64 + MIN_INT64) <= (MAX_INT64 + Subtrahend) < MAX_INT64
  //
  if (((Subtrahend > 0) && (Minuend < (MIN_INT64 + Subtrahend))) ||
      ((Subtrahend < 0) && (Minuend > (MAX_INT64 + Subtrahend)))) {
    *Result = INT64_ERROR;
    Status = RETURN_BUFFER_TOO_SMALL;
  } else {
    *Result = Minuend - Subtrahend;
    Status = RETURN_SUCCESS;
  }

  return Status;
}

//
// Signed multiplication functions
//

/**
  INT8 multiplication

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to INT8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Multiplicand  A number that is to be multiplied by another
  @param[in]   Multiplier    A number by which the multiplicand is to be multiplied
  @param[out]  Result        Pointer to the result of multiplication

  @retval  RETURN_SUCCESS            Successful multiplication
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt8Mult (
  IN  INT8  Multiplicand,
  IN  INT8  Multiplier,
  OUT INT8  *Result
  )
{
  return SafeInt32ToInt8 (((INT32)Multiplier) *((INT32)Multiplicand), Result);
}

/**
  CHAR8 multiplication

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to CHAR8_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Multiplicand  A number that is to be multiplied by another
  @param[in]   Multiplier    A number by which the multiplicand is to be multiplied
  @param[out]  Result        Pointer to the result of multiplication

  @retval  RETURN_SUCCESS            Successful multiplication
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeChar8Mult (
  IN  CHAR8  Multiplicand,
  IN  CHAR8  Multiplier,
  OUT CHAR8  *Result
  )
{
  INT32  Multiplicand32;
  INT32  Multiplier32;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  Multiplicand32 = (INT32)Multiplicand;
  Multiplier32   = (INT32)Multiplier;
  if (Multiplicand32 < 0 || Multiplicand32 > MAX_INT8) {
    *Result = CHAR8_ERROR;
    return RETURN_BUFFER_TOO_SMALL;
  }
  if (Multiplier32 < 0 || Multiplier32 > MAX_INT8) {
    *Result = CHAR8_ERROR;
    return RETURN_BUFFER_TOO_SMALL;
  }

  return SafeInt32ToChar8 (Multiplicand32 * Multiplier32, Result);
}

/**
  INT16 multiplication

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to INT16_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Multiplicand  A number that is to be multiplied by another
  @param[in]   Multiplier    A number by which the multiplicand is to be multiplied
  @param[out]  Result        Pointer to the result of multiplication

  @retval  RETURN_SUCCESS            Successful multiplication
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt16Mult (
  IN  INT16  Multiplicand,
  IN  INT16  Multiplier,
  OUT INT16  *Result
  )
{
  return SafeInt32ToInt16 (((INT32)Multiplicand) *((INT32)Multiplier), Result);
}

/**
  INT32 multiplication

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to INT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Multiplicand  A number that is to be multiplied by another
  @param[in]   Multiplier    A number by which the multiplicand is to be multiplied
  @param[out]  Result        Pointer to the result of multiplication

  @retval  RETURN_SUCCESS            Successful multiplication
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt32Mult (
  IN  INT32  Multiplicand,
  IN  INT32  Multiplier,
  OUT INT32  *Result
  )
{
  return SafeInt64ToInt32 (MultS64x64 (Multiplicand, Multiplier), Result);
}

/**
  INT64 multiplication

  Performs the requested operation using the input parameters into a value
  specified by Result type and stores the converted value into the caller
  allocated output buffer specified by Result.  The caller must pass in a
  Result buffer that is at least as large as the Result type.

  If Result is NULL, RETURN_INVALID_PARAMETER is returned.

  If the requested operation results in an overflow or an underflow condition,
  then Result is set to INT64_ERROR and RETURN_BUFFER_TOO_SMALL is returned.

  @param[in]   Multiplicand  A number that is to be multiplied by another
  @param[in]   Multiplier    A number by which the multiplicand is to be multiplied
  @param[out]  Result        Pointer to the result of multiplication

  @retval  RETURN_SUCCESS            Successful multiplication
  @retval  RETURN_BUFFER_TOO_SMALL   Overflow
  @retval  RETURN_INVALID_PARAMETER  Result is NULL
**/
RETURN_STATUS
EFIAPI
SafeInt64Mult (
  IN  INT64  Multiplicand,
  IN  INT64  Multiplier,
  OUT INT64  *Result
  )
{
  RETURN_STATUS  Status;
  UINT64         UnsignedMultiplicand;
  UINT64         UnsignedMultiplier;
  UINT64         UnsignedResult;

  if (Result == NULL) {
    return RETURN_INVALID_PARAMETER;
  }

  //
  // Split into sign and magnitude, do unsigned operation, apply sign.
  //
  if (Multiplicand < 0) {
    //
    // Avoid negating the most negative number.
    //
    UnsignedMultiplicand = ((UINT64)(- (Multiplicand + 1))) + 1;
  } else {
    UnsignedMultiplicand = (UINT64)Multiplicand;
  }

  if (Multiplier < 0) {
    //
    // Avoid negating the most negative number.
    //
    UnsignedMultiplier = ((UINT64)(- (Multiplier + 1))) + 1;
  } else {
    UnsignedMultiplier = (UINT64)Multiplier;
  }

  Status = SafeUint64Mult (UnsignedMultiplicand, UnsignedMultiplier, &UnsignedResult);
  if (!RETURN_ERROR (Status)) {
    if ((Multiplicand < 0) != (Multiplier < 0)) {
      if (UnsignedResult > MIN_INT64_MAGNITUDE) {
        *Result = INT64_ERROR;
        Status = RETURN_BUFFER_TOO_SMALL;
      } else if (UnsignedResult == MIN_INT64_MAGNITUDE) {
        *Result = MIN_INT64;
      } else {
        *Result = - ((INT64)UnsignedResult);
      }
    } else {
      if (UnsignedResult > MAX_INT64) {
        *Result = INT64_ERROR;
        Status = RETURN_BUFFER_TOO_SMALL;
      } else {
        *Result = (INT64)UnsignedResult;
      }
    }
  } else {
    *Result = INT64_ERROR;
  }
  return Status;
}