Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754114AbaLDKbI (ORCPT ); Thu, 4 Dec 2014 05:31:08 -0500 Received: from mail-lb0-f177.google.com ([209.85.217.177]:50846 "EHLO mail-lb0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753569AbaLDKbF (ORCPT ); Thu, 4 Dec 2014 05:31:05 -0500 From: Rasmus Villemoes To: Grant Grundler Cc: Rasmus Villemoes , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] net: tulip: Remove private "strncmp" Date: Thu, 4 Dec 2014 11:30:40 +0100 Message-Id: <1417689040-14958-1-git-send-email-linux@rasmusvillemoes.dk> X-Mailer: git-send-email 2.0.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The comment says that the built-in strncmp didn't work. That is not surprising, as apparently "str" semantics are not really what is wanted (hint: de4x5_strncmp only stops when two different bytes are encountered or the end is reached; not if either byte happens to be 0). de4x5_strncmp is actually a memcmp (except for the signature and that bytes are not necessarily treated as unsigned char); since only the boolean value of the result is used we can just replace de4x5_strncmp with memcmp. Signed-off-by: Rasmus Villemoes --- Notes: I don't know if the comment meant to say 3 bytes, or if the code compares meaningful chunks of memory (the first three bytes of &lp->srom span 1.5 fields, and the three bytes from (char*)&lp->srom + 0x10 are &lp->srom.{id_block_crc,reserved2,version} - it seems odd that these chunks should ever be equal to each other and to the enet_det[i]). Whether or not the current code works, this patch shouldn't change the semantics, and I'd like to get rid of de4x5_strncmp since it is not, in fact, a strncmp. drivers/net/ethernet/dec/tulip/de4x5.c | 20 +++----------------- 1 file changed, 3 insertions(+), 17 deletions(-) diff --git a/drivers/net/ethernet/dec/tulip/de4x5.c b/drivers/net/ethernet/dec/tulip/de4x5.c index cf8b6ff..badff18 100644 --- a/drivers/net/ethernet/dec/tulip/de4x5.c +++ b/drivers/net/ethernet/dec/tulip/de4x5.c @@ -995,7 +995,6 @@ static void de4x5_dbg_mii(struct net_device *dev, int k); static void de4x5_dbg_media(struct net_device *dev); static void de4x5_dbg_srom(struct de4x5_srom *p); static void de4x5_dbg_rx(struct sk_buff *skb, int len); -static int de4x5_strncmp(char *a, char *b, int n); static int dc21041_infoleaf(struct net_device *dev); static int dc21140_infoleaf(struct net_device *dev); static int dc21142_infoleaf(struct net_device *dev); @@ -4102,8 +4101,7 @@ get_hw_addr(struct net_device *dev) } /* -** Test for enet addresses in the first 32 bytes. The built-in strncmp -** didn't seem to work here...? +** Test for enet addresses in the first 32 bytes. */ static int de4x5_bad_srom(struct de4x5_private *lp) @@ -4111,8 +4109,8 @@ de4x5_bad_srom(struct de4x5_private *lp) int i, status = 0; for (i = 0; i < ARRAY_SIZE(enet_det); i++) { - if (!de4x5_strncmp((char *)&lp->srom, (char *)&enet_det[i], 3) && - !de4x5_strncmp((char *)&lp->srom+0x10, (char *)&enet_det[i], 3)) { + if (!memcmp(&lp->srom, &enet_det[i], 3) && + !memcmp((char *)&lp->srom+0x10, &enet_det[i], 3)) { if (i == 0) { status = SMC; } else if (i == 1) { @@ -4125,18 +4123,6 @@ de4x5_bad_srom(struct de4x5_private *lp) return status; } -static int -de4x5_strncmp(char *a, char *b, int n) -{ - int ret=0; - - for (;n && !ret; n--) { - ret = *a++ - *b++; - } - - return ret; -} - static void srom_repair(struct net_device *dev, int card) { -- 2.0.4 -- 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/