MdePkg/BaseLib: Add safe string functions that convert str to value

Add the following 8 APIs:
[Ascii]StrDecimalToUintnS
[Ascii]StrDecimalToUint64S
[Ascii]StrHexToUintnS
[Ascii]StrHexToUint64S

These safe version APIs are used to enhance their counterpart (APIs
without trailing 'S' in function names).

These safe version APIs perform checks to the input string and will return
relative status to reflect the check result:
When the input string exceeds the range of UINTN/64, these APIs will
return RETURN_UNSUPPORTED and store MAX_UINTN/64 in the output data.
When no conversion can be performed for the input string, these APIs will
return RETURN_SUCCESS and store 0 in the output data.

The optional parameter 'EndPointer', if provided, will point to the
character that stopped the scan.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>

MdePkg/Library/BaseLib/BaseLibInternals.h

@@ -1,7 +1,7 @@
 /** @file
   Declaration of internal functions in BaseLib.
 
-  Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
   This program and the accompanying materials
   are licensed and made available under the terms and conditions of the BSD License
   which accompanies this distribution.  The full text of the license may be found at
@@ -477,6 +477,170 @@ InternalLongJump (
   );
 
 
+/**
+  Check if a Unicode character is a decimal character.
+
+  This internal function checks if a Unicode character is a
+  decimal character. The valid decimal character is from
+  L'0' to L'9'.
+
+  @param  Char  The character to check against.
+
+  @retval TRUE  If the Char is a decmial character.
+  @retval FALSE If the Char is not a decmial character.
+
+**/
+BOOLEAN
+EFIAPI
+InternalIsDecimalDigitCharacter (
+  IN      CHAR16                    Char
+  );
+
+
+/**
+  Convert a Unicode character to upper case only if
+  it maps to a valid small-case ASCII character.
+
+  This internal function only deal with Unicode character
+  which maps to a valid small-case ASCII character, i.e.
+  L'a' to L'z'. For other Unicode character, the input character
+  is returned directly.
+
+  @param  Char  The character to convert.
+
+  @retval LowerCharacter   If the Char is with range L'a' to L'z'.
+  @retval Unchanged        Otherwise.
+
+**/
+CHAR16
+EFIAPI
+InternalCharToUpper (
+  IN      CHAR16                    Char
+  );
+
+
+/**
+  Convert a Unicode character to numerical value.
+
+  This internal function only deal with Unicode character
+  which maps to a valid hexadecimal ASII character, i.e.
+  L'0' to L'9', L'a' to L'f' or L'A' to L'F'. For other
+  Unicode character, the value returned does not make sense.
+
+  @param  Char  The character to convert.
+
+  @return The numerical value converted.
+
+**/
+UINTN
+EFIAPI
+InternalHexCharToUintn (
+  IN      CHAR16                    Char
+  );
+
+
+/**
+  Check if a Unicode character is a hexadecimal character.
+
+  This internal function checks if a Unicode character is a
+  decimal character.  The valid hexadecimal character is
+  L'0' to L'9', L'a' to L'f', or L'A' to L'F'.
+
+
+  @param  Char  The character to check against.
+
+  @retval TRUE  If the Char is a hexadecmial character.
+  @retval FALSE If the Char is not a hexadecmial character.
+
+**/
+BOOLEAN
+EFIAPI
+InternalIsHexaDecimalDigitCharacter (
+  IN      CHAR16                    Char
+  );
+
+
+/**
+  Check if a ASCII character is a decimal character.
+
+  This internal function checks if a Unicode character is a
+  decimal character. The valid decimal character is from
+  '0' to '9'.
+
+  @param  Char  The character to check against.
+
+  @retval TRUE  If the Char is a decmial character.
+  @retval FALSE If the Char is not a decmial character.
+
+**/
+BOOLEAN
+EFIAPI
+InternalAsciiIsDecimalDigitCharacter (
+  IN      CHAR8                     Char
+  );
+
+
+/**
+  Converts a lowercase Ascii character to upper one.
+
+  If Chr is lowercase Ascii character, then converts it to upper one.
+
+  If Value >= 0xA0, then ASSERT().
+  If (Value & 0x0F) >= 0x0A, then ASSERT().
+
+  @param  Chr   one Ascii character
+
+  @return The uppercase value of Ascii character
+
+**/
+CHAR8
+EFIAPI
+InternalBaseLibAsciiToUpper (
+  IN      CHAR8                     Chr
+  );
+
+
+/**
+  Check if a ASCII character is a hexadecimal character.
+
+  This internal function checks if a ASCII character is a
+  decimal character.  The valid hexadecimal character is
+  L'0' to L'9', L'a' to L'f', or L'A' to L'F'.
+
+
+  @param  Char  The character to check against.
+
+  @retval TRUE  If the Char is a hexadecmial character.
+  @retval FALSE If the Char is not a hexadecmial character.
+
+**/
+BOOLEAN
+EFIAPI
+InternalAsciiIsHexaDecimalDigitCharacter (
+  IN      CHAR8                    Char
+  );
+
+
+/**
+  Convert a ASCII character to numerical value.
+
+  This internal function only deal with Unicode character
+  which maps to a valid hexadecimal ASII character, i.e.
+  '0' to '9', 'a' to 'f' or 'A' to 'F'. For other
+  ASCII character, the value returned does not make sense.
+
+  @param  Char  The character to convert.
+
+  @return The numerical value converted.
+
+**/
+UINTN
+EFIAPI
+InternalAsciiHexCharToUintn (
+  IN      CHAR8                    Char
+  );
+
+
 //
 // Ia32 and x64 specific functions
 //