[PATCH] ShellPkg: Fix a bug ">>v" cannot append data to environment variable

[Ruiyu Ni <ruiyu.ni@intel.com>]

From: chen881220 <ai_terran@foxmail.com>

When ">v" is used to redirect the command output to environment
variable, the ending "\r\n\0" is removed before setting to environment
variable but the length is not updated.
It causes ">>v" fails to append data to the environment variable
created by ">v".
The patch fixes the above bug.

Signed-off-by: Chen A Chen <chen.a.chen@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Jaben Carsey <jaben.carsey@intel.com>
---
 ShellPkg/Application/Shell/FileHandleWrappers.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/ShellPkg/Application/Shell/FileHandleWrappers.c b/ShellPkg/Application/Shell/FileHandleWrappers.c
index 3c11d82..67ca8e7 100644
--- a/ShellPkg/Application/Shell/FileHandleWrappers.c
+++ b/ShellPkg/Application/Shell/FileHandleWrappers.c
@@ -1074,6 +1074,10 @@ FileInterfaceEnvClose(
            (((CHAR16*)NewBuffer)[TotalSize / sizeof (CHAR16) - 3] == CHAR_CARRIAGE_RETURN)
          ) {
         ((CHAR16*)NewBuffer)[TotalSize / sizeof (CHAR16) - 3] = CHAR_NULL;
+        //
+        // If the NewBuffer end with \r\n\0, We will repace '\r' by '\0' and then update TotalSize.
+        //
+        TotalSize -= sizeof(CHAR16) * 2;
       }
 
       if (Volatile) {
-- 
2.9.0.windows.1