MdePkg/BaseLib: Base64Decode(): don't declare variables in nested blocks

The EDK II C Coding Standards Specification (v2.20) strongly discourages
variable declarations in nested block scope:

5       Source Files
5.4     Code File Structure
5.4.1   Scoping Rules
5.4.1.1 Scope

> Block (local) Scope
>
> [...]
>
> Data declarations may follow the opening brace of a compound statement,
> regardless of nesting depth, and before any code generating statements
> have been entered. Other than at the outermost block of a function body,
> this type of declaration is strongly discouraged.

Hoist such variable declarations in Base64Decode() to the outermost
function scope.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Cc: Zhichao Gao <zhichao.gao@intel.com>
Fixes: 35e242b698cdc6205e99a6d6a188bf27fecf9fb4
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1980
Reported-by: Zhichao Gao <zhichao.gao@intel.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Rebecca Cran <rebecca@bsdio.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daude <philmd@redhat.com>

1 files changed, 3 insertions, 4 deletions

diff --git a/MdePkg/Library/BaseLib/String.c b/MdePkg/Library/BaseLib/String.c
index 6198ccbc96..45198373f2 100644
--- a/MdePkg/Library/BaseLib/String.c
+++ b/MdePkg/Library/BaseLib/String.c
@@ -1978,6 +1978,9 @@ Base64Decode (
   UINT32  Accumulator;

   UINTN   OriginalDestinationSize;

   UINTN   SourceIndex;

+  CHAR8   SourceChar;

+  UINT32  Base64Value;

+  UINT8   DestinationOctet;

 

   if (DestinationSize == NULL) {

     return RETURN_INVALID_PARAMETER;

@@ -2054,10 +2057,6 @@ Base64Decode (
   // Decoding loop.

   //

   for (SourceIndex = 0; SourceIndex < SourceSize; SourceIndex++) {

-    CHAR8  SourceChar;

-    UINT32 Base64Value;

-    UINT8  DestinationOctet;

-

     SourceChar = Source[SourceIndex];

 

     //