commit 410bc115ec4236936e2966a59079ea4facb89ace
author Simon Butcher <simon.butcher@arm.com> Thu Feb 02 08:46:53 2017 +0000
committer Andres AG <andres.amayagarcia@arm.com> Wed Feb 08 12:04:27 2017 +0000
tree 46468191119921ee451f853b304bfb81d2708544
parent cde8035e570c757857e6ea5f291ad2c21b54ea3d

Add comment to integer overflow fix in base64.c

Adds clarifying comment to the integer overflow fix in base64.c

library/base64.c

diff --git a/library/base64.c b/library/base64.c
index 305afc5..f06b57b 100644
--- a/library/base64.c
+++ b/library/base64.c
@@ -192,6 +192,10 @@
         return( 0 );
     }
 
+    /* The following expression is to calculate the following formula without
+     * risk of integer overflow in n:
+     *     n = ( ( n * 6 ) + 7 ) >> 3;
+     */
     n = ( 6 * ( n >> 3 ) ) + ( ( 6 * ( n & 0x7 ) + 7 ) >> 3 );
     n -= j;