From patchwork Fri Jul 19 21:26:13 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eugeniu Rosca X-Patchwork-Id: 1134307 X-Patchwork-Delegate: trini@ti.com Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.denx.de (client-ip=81.169.180.215; helo=lists.denx.de; envelope-from=u-boot-bounces@lists.denx.de; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="SgoR+bgR"; dkim-atps=neutral Received: from lists.denx.de (dione.denx.de [81.169.180.215]) by ozlabs.org (Postfix) with ESMTP id 45r4020cMGz9s4Y for ; Sat, 20 Jul 2019 07:29:38 +1000 (AEST) Received: by lists.denx.de (Postfix, from userid 105) id BA287C21E36; Fri, 19 Jul 2019 21:28:29 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on lists.denx.de X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=FREEMAIL_FROM, T_DKIM_INVALID autolearn=unavailable autolearn_force=no version=3.4.0 Received: from lists.denx.de (localhost [IPv6:::1]) by lists.denx.de (Postfix) with ESMTP id D37A4C21DFA; Fri, 19 Jul 2019 21:28:18 +0000 (UTC) Received: by lists.denx.de (Postfix, from userid 105) id 7E58BC21DD7; Fri, 19 Jul 2019 21:28:11 +0000 (UTC) Received: from mail-wm1-f65.google.com (mail-wm1-f65.google.com [209.85.128.65]) by lists.denx.de (Postfix) with ESMTPS id 34A3CC21E29 for ; Fri, 19 Jul 2019 21:28:11 +0000 (UTC) Received: by mail-wm1-f65.google.com with SMTP id h19so24520834wme.0 for ; Fri, 19 Jul 2019 14:28:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=hxfmjgANdzbikKdslYDP+3V8D4miN0voPRjt4m7UWV0=; b=SgoR+bgRk0W21+rd8nCrYUkriluzQpUiBqf+yuSR7mw1wFWE4hCJcmPSobTB8vfBdC G7aL1YaHKTFf6LhLIaCpGf215wNocupGNo9w3FzA76asiKXwiFRZ1lFn8FdUHZiDKL70 zGIOfAolyEV0OLbylPm4FJpUV/KldYgA9Sqw7iHseoxP/2oDmAqOKNMuD6MDvW8cFUPb sJjtxmhK/wZRsbTJGUWN75bH5SRh26Zs11BdIcTlhQQyUYwRPwY8UHRY/U1UqYhoNeHc zgTM7SZd/aLUyxIhKUDVv3rLNTG239yMc3VuFKmmIDISR2iRX/XV25jUn8NctHPPfu52 avbA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=hxfmjgANdzbikKdslYDP+3V8D4miN0voPRjt4m7UWV0=; b=lgUPBUzgQy7rpybUoaNLWLgOGdiVgLnarehIkks6zbkc6xpLNemNZBDHOYpq0yWlc6 drqnX5eISsWR+m53K6ZP6ATp4raeEOcKISmBseXqYkG675dGZOkznqZVZLevcQNaOLwO w5F9tE/J2IQLnJ0OFiM1NiFvVJBfCZSxY5Vao+9rBeejszuLVIoZ0NwcTmnzcIskG2J1 s27LgrFL47W5aEHj9i6sSdzSOe3tlxlMTk3E9yuH7rOT/4Ua3lCH2DpVYWCcrxV4WdZs akjbMPBJJEH/aNKJ1dKx6prvIFTYCSMx4WI/0Wgwl9w18Efj3ysCAqj9OtGjnuNAzSHw I1Lg== X-Gm-Message-State: APjAAAXsjw1LGtf84O+kglgcDaf6/0M+SsacCX/sCUz6sNIBubRjSwZI gZQtUtUlItk64bkqJVza1UDNpe0CTNbqlA== X-Google-Smtp-Source: APXvYqxhZB9HI7cmN7ZIS+ItRuHnZV1GVXdPIX5AFCDFhNdiC8dUfYxgGSNouZ607bhfukhEtyAzZg== X-Received: by 2002:a05:600c:214c:: with SMTP id v12mr49697417wml.28.1563571690664; Fri, 19 Jul 2019 14:28:10 -0700 (PDT) Received: from erosca.t-mobile.de ([84.117.13.234]) by smtp.gmail.com with ESMTPSA id 32sm26309800wrh.76.2019.07.19.14.28.09 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Fri, 19 Jul 2019 14:28:10 -0700 (PDT) From: Eugeniu Rosca X-Google-Original-From: Eugeniu Rosca To: u-boot@lists.denx.de, Simon Glass , Sam Protsenko , Igor Opaniuk , Tom Rini Date: Fri, 19 Jul 2019 23:26:13 +0200 Message-Id: <20190719212614.25527-4-erosca@de.adit-jv.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190719212614.25527-1-erosca@de.adit-jv.com> References: <20190719212614.25527-1-erosca@de.adit-jv.com> MIME-Version: 1.0 Cc: Eugeniu Rosca , Eugeniu Rosca Subject: [U-Boot] [PATCH v3 3/4] cmd: bcb: Use strcmp() instead of strncmp() for string literals X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.18 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" Quote from https://patchwork.ozlabs.org/patch/1104244/#2210814: ----------8<----------- strncmp() is chosen for the sake of paranoid/defensive programming. Indeed, strncmp() is not really needed when comparing a variable with a string literal. We expect strcmp() to behave safely even if the string variable is not NUL-terminated. In the same scenario, Linux v5.2-rc7 uses both strcmp() and strncmp(), but the frequency of strcmp() is higher: $ git --version git version 2.22.0 $ (Linux 5.2-rc7) git grep -En 'strncmp\([^"]*"[[:alnum:]]+"' | wc -l 1066 $ (Linux 5.2-rc7) git grep -En 'strcmp\([^"]*"[[:alnum:]]+"' | wc -l 1968 A quick "strcmp vs strncmp" object size test shows that strcmp() generates smaller memory footprint (gcc-8, x86_64): $ (U-Boot) size cmd/bcb-strncmp.o cmd/bcb-strcmp.o text data bss dec hex filename 3373 400 2048 5821 16bd cmd/bcb-strncmp.o 3314 400 2048 5762 1682 cmd/bcb-strcmp.o So, overall, I agree to use strcmp() whenever variables are compared with string literals. ----------8<----------- Fixes: db7b7a05b267 ("cmd: Add 'bcb' command to read/modify/write BCB fields") Reported-by: Simon Glass Signed-off-by: Eugeniu Rosca Reviewed-by: Sam Protsenko Reviewed-by: Igor Opaniuk --- v3: - No changes - Added 'Reviewed-by: Sam Protsenko' from v2 v2: - Fixed accidental rename of field/size variables in bcb_field_get() - https://patchwork.ozlabs.org/patch/1131358/ v1: - https://patchwork.ozlabs.org/patch/1131306/ --- cmd/bcb.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/cmd/bcb.c b/cmd/bcb.c index 3b1c7434e287..fa9fdeeb0dfc 100644 --- a/cmd/bcb.c +++ b/cmd/bcb.c @@ -24,17 +24,17 @@ static struct bootloader_message bcb = { { 0 } }; static int bcb_cmd_get(char *cmd) { - if (!strncmp(cmd, "load", sizeof("load"))) + if (!strcmp(cmd, "load")) return BCB_CMD_LOAD; - if (!strncmp(cmd, "set", sizeof("set"))) + if (!strcmp(cmd, "set")) return BCB_CMD_FIELD_SET; - if (!strncmp(cmd, "clear", sizeof("clear"))) + if (!strcmp(cmd, "clear")) return BCB_CMD_FIELD_CLEAR; - if (!strncmp(cmd, "test", sizeof("test"))) + if (!strcmp(cmd, "test")) return BCB_CMD_FIELD_TEST; - if (!strncmp(cmd, "store", sizeof("store"))) + if (!strcmp(cmd, "store")) return BCB_CMD_STORE; - if (!strncmp(cmd, "dump", sizeof("dump"))) + if (!strcmp(cmd, "dump")) return BCB_CMD_FIELD_DUMP; else return -1; @@ -85,19 +85,19 @@ err: static int bcb_field_get(char *name, char **field, int *size) { - if (!strncmp(name, "command", sizeof("command"))) { + if (!strcmp(name, "command")) { *field = bcb.command; *size = sizeof(bcb.command); - } else if (!strncmp(name, "status", sizeof("status"))) { + } else if (!strcmp(name, "status")) { *field = bcb.status; *size = sizeof(bcb.status); - } else if (!strncmp(name, "recovery", sizeof("recovery"))) { + } else if (!strcmp(name, "recovery")) { *field = bcb.recovery; *size = sizeof(bcb.recovery); - } else if (!strncmp(name, "stage", sizeof("stage"))) { + } else if (!strcmp(name, "stage")) { *field = bcb.stage; *size = sizeof(bcb.stage); - } else if (!strncmp(name, "reserved", sizeof("reserved"))) { + } else if (!strcmp(name, "reserved")) { *field = bcb.reserved; *size = sizeof(bcb.reserved); } else {