commit 74ae020295e47a6612be4780d3818456f640ceb7
author Simon Butcher <simon.butcher@arm.com> Thu Feb 02 08:46:53 2017 +0000
committer Simon Butcher <simon.butcher@arm.com> Thu Feb 02 08:46:53 2017 +0000
tree 9d149e4725dea59afe38d8cb210879141abf4ec4
parent dc210178f916ce4c1b00eb0b4f2c95f9fa06f86d

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;