The function wfShorthandToInteger() is precisely for that.

The previous way only worked for megabytes, which made it
'raise' the memory limit from several gigabytes to 50M

diff --git a/includes/installer/Installer.php b/includes/installer/Installer.php
index c33606c..507ba2e 100644 (file)
--- a/includes/installer/Installer.php
+++ b/includes/installer/Installer.php
@@ -748,11 +748,7 @@ abstract class Installer {
                        return true;
                }
 
-               $n = intval( $limit );
-
-               if( preg_match( '/^([0-9]+)[Mm]$/', trim( $limit ), $m ) ) {
-                       $n = intval( $m[1] * ( 1024 * 1024 ) );
-               }
+               $n = wfShorthandToInteger( $limit );
 
                if( $n < $this->minMemorySize * 1024 * 1024 ) {
                        $newLimit = "{$this->minMemorySize}M";