=========== Original jpeg source code fragment: ===================


switch (code = param_read_int(plist, (param_name = "JPEGQ"), &jq)) {
	case 0:
	    if (jq < 0 || jq > 100)
		ecode = gs_error_limitcheck;
	    else
		break;
	    goto jqe;
	default:
	    ecode = code;
	  jqe:param_signal_error(plist, param_name, ecode);
	case 1:
	    break;
    }

=================== First rewritten version: =====================

param_name = "JPEGQ" ;

code = param_read_int( plist , param_name , &jq ) ;

if( code==0 )
	{
	if( jq < 0 || jq > 100 )
		{
		ecode = gs_error_limitcheck ;
		param_signal_error( plist , param_name , ecode ) ;
		}
	}
else if( code!=1 )
	{
	ecode = code;
	param_signal_error(plist, param_name, ecode);
	}

=========== Correct + improved + obvious version: ===========


param_name = "JPEGQ" ;

code = param_read_int( plist , param_name , &jq ) ;

if( code==0 ) 
	{
	if( jq < 0 || jq > 100 )
		{
		ecode = gs_error_limitcheck ;
		param_signal_error( plist , param_name , ecode ) ;
		}
	}
else if( code < 0 )
	{
	ecode = code;
	param_signal_error(plist, param_name, ecode);
	}

/* 
in english the program sequence is:

set parameter name, 
read it from command line, 
quit if is out of range integer, 
quit if it is garbage

This cannot contain bugs!
*/

====================================================================