From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753210AbcBOLMz (ORCPT ); Mon, 15 Feb 2016 06:12:55 -0500 Received: from mail-wm0-f41.google.com ([74.125.82.41]:35982 "EHLO mail-wm0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752824AbcBOLMw (ORCPT ); Mon, 15 Feb 2016 06:12:52 -0500 Date: Mon, 15 Feb 2016 11:12:49 +0000 From: Matt Fleming To: Jason Andryuk Cc: Peter Jones , linux-kernel@vger.kernel.org, Matthew Garrett , Laszlo Ersek , linux-efi@vger.kernel.org Subject: Re: [PATCH] lib/ucs2_string: Correct ucs2 -> utf8 conversion Message-ID: <20160215111249.GD2591@codeblueprint.co.uk> References: <1455318813-30667-1-git-send-email-jandryuk@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1455318813-30667-1-git-send-email-jandryuk@gmail.com> User-Agent: Mutt/1.5.24+41 (02bc14ed1569) (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (Cc'ing Laszlo and linux-efi) On Fri, 12 Feb, at 11:13:33PM, Jason Andryuk wrote: > The comparisons should be >= since 0x800 and 0x80 require an additional bit > to store. > > For the 3 byte case, the existing shift would drop off 2 more bits than > intended. > > For the 2 byte case, there should be 5 bits bits in byte 1, and 6 bits in > byte 2. > > Signed-off-by: Jason Andryuk > --- > > Tested in user space, but not in the kernel. Conversions now match > python's unicode conversions. > > lib/ucs2_string.c | 14 +++++++------- > 1 file changed, 7 insertions(+), 7 deletions(-) Thanks Jason. Peter, Laszlo, any comments? > diff --git a/lib/ucs2_string.c b/lib/ucs2_string.c > index 17dd74e..f0b323a 100644 > --- a/lib/ucs2_string.c > +++ b/lib/ucs2_string.c > @@ -59,9 +59,9 @@ ucs2_utf8size(const ucs2_char_t *src) > for (i = 0; i < ucs2_strlen(src); i++) { > u16 c = src[i]; > > - if (c > 0x800) > + if (c >= 0x800) > j += 3; > - else if (c > 0x80) > + else if (c >= 0x80) > j += 2; > else > j += 1; > @@ -88,19 +88,19 @@ ucs2_as_utf8(u8 *dest, const ucs2_char_t *src, unsigned long maxlength) > for (i = 0; maxlength && i < limit; i++) { > u16 c = src[i]; > > - if (c > 0x800) { > + if (c >= 0x800) { > if (maxlength < 3) > break; > maxlength -= 3; > dest[j++] = 0xe0 | (c & 0xf000) >> 12; > - dest[j++] = 0x80 | (c & 0x0fc0) >> 8; > + dest[j++] = 0x80 | (c & 0x0fc0) >> 6; > dest[j++] = 0x80 | (c & 0x003f); > - } else if (c > 0x80) { > + } else if (c >= 0x80) { > if (maxlength < 2) > break; > maxlength -= 2; > - dest[j++] = 0xc0 | (c & 0xfe0) >> 5; > - dest[j++] = 0x80 | (c & 0x01f); > + dest[j++] = 0xc0 | (c & 0x7c0) >> 6; > + dest[j++] = 0x80 | (c & 0x03f); > } else { > maxlength -= 1; > dest[j++] = c & 0x7f; > -- > 2.4.3 >