Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262934AbTE2WWT (ORCPT ); Thu, 29 May 2003 18:22:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262946AbTE2WWT (ORCPT ); Thu, 29 May 2003 18:22:19 -0400 Received: from air-2.osdl.org ([65.172.181.6]:51942 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S262934AbTE2WWR (ORCPT ); Thu, 29 May 2003 18:22:17 -0400 Date: Thu, 29 May 2003 15:36:03 -0700 From: Dave Olien To: torvalds@transmeta.com Cc: linux-kernel@vger.kernel.org Subject: [PATCH] sparse tool handling of escaped characters in strings Message-ID: <20030529223603.GA8958@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, Linus. I'm just beginning to look over your sparse tool library. I decided to start with something simple. Running your check tool on the 2.5.70 kernel produces 25 warnings of the forms: warning: drivers/char/n_tty.c:198:35: Unknown escape 'r' warning: drivers/char/n_tty.c:225:11: Unknown escape 'b' warning: drivers/char/n_tty.c:547:17: Unknown escape 'a' They come from character strings that contain escaped characters that escapechar() in tokenize.c didn't recognize. I added cases for these characters. The warning below is a little more interesting. warning: fs/proc/array.c:338:1: Unknown escape ' ' It comes from a string that is continued on multiple lines, of the form: printf("abcdef\ ghijkl"); This is different from the other cases because the \ character should never appear in the parsed string. As a first fix, I've made escapechar() call itself recursively. One flaw with this fix is that escapechar() will mark the first character on the second line of the input string as "escaped": /* Mark it as escaped */ value |= 0x100; But, none of the callers to escapechar() ever use or preserve this information. Can this "escaped" character information be removed. Or, I could add a flag (ugh) that causes the code to NOT add the escape flag in this particular case. Or, I could find a different solution to this case. Thanks! Dave Olien OSDL -------------------------------------------------------------------------- --- sparse_original/tokenize.c 2003-05-29 14:22:20.000000000 -0700 +++ sparse_test/tokenize.c 2003-05-29 15:19:25.000000000 -0700 @@ -340,18 +340,39 @@ next = nextchar(stream); if (value != type) { switch (value) { - case 'n': - value = '\n'; + case 'a': + value = '\a'; + break; + case 'b': + value = '\b'; break; case 't': value = '\t'; break; + case 'n': + value = '\n'; + break; + case 'v': + value = '\v'; + break; + case 'f': + value = '\f'; + break; + case 'r': + value = '\r'; + break; + case 'e': + value = '\e'; + break; case '\\': break; case '\'': break; case '"': break; + case '\n': + next = escapechar(next, type, stream, &value); + break; case '0'...'7': { int nr = 2; value -= '0'; - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/