Return-Path: X-Original-To: notmuch@notmuchmail.org Delivered-To: notmuch@notmuchmail.org Received: from localhost (localhost [127.0.0.1]) by olra.theworths.org (Postfix) with ESMTP id 2C4C8431FC9 for ; Fri, 24 Oct 2014 05:49:33 -0700 (PDT) X-Virus-Scanned: Debian amavisd-new at olra.theworths.org X-Spam-Flag: NO X-Spam-Score: -2.3 X-Spam-Level: X-Spam-Status: No, score=-2.3 tagged_above=-999 required=5 tests=[RCVD_IN_DNSWL_MED=-2.3] autolearn=disabled Received: from olra.theworths.org ([127.0.0.1]) by localhost (olra.theworths.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id T+4I7UWAPhti for ; Fri, 24 Oct 2014 05:49:24 -0700 (PDT) Received: from dmz-mailsec-scanner-4.mit.edu (dmz-mailsec-scanner-4.mit.edu [18.9.25.15]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by olra.theworths.org (Postfix) with ESMTPS id 20ACB431FBD for ; Fri, 24 Oct 2014 05:49:24 -0700 (PDT) X-AuditID: 1209190f-f79aa6d000005b45-f3-544a4ad32ed3 Received: from mailhub-auth-2.mit.edu ( [18.7.62.36]) (using TLS with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by dmz-mailsec-scanner-4.mit.edu (Symantec Messaging Gateway) with SMTP id 45.7B.23365.3DA4A445; Fri, 24 Oct 2014 08:49:23 -0400 (EDT) Received: from outgoing.mit.edu (outgoing-auth-1.mit.edu [18.9.28.11]) by mailhub-auth-2.mit.edu (8.13.8/8.9.2) with ESMTP id s9OCnLsC013437; Fri, 24 Oct 2014 08:49:21 -0400 Received: from drake.dyndns.org (216-15-114-40.c3-0.arl-ubr1.sbo-arl.ma.cable.rcn.com [216.15.114.40]) (authenticated bits=0) (User authenticated as amdragon@ATHENA.MIT.EDU) by outgoing.mit.edu (8.13.8/8.12.4) with ESMTP id s9OCnIF4021584 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NOT); Fri, 24 Oct 2014 08:49:20 -0400 Received: from amthrax by drake.dyndns.org with local (Exim 4.84) (envelope-from ) id 1XheIx-0004k2-64; Fri, 24 Oct 2014 08:49:19 -0400 From: Austin Clements To: notmuch@notmuchmail.org Subject: [PATCH v3.1 3/9] lib: Introduce macros for bit operations Date: Fri, 24 Oct 2014 08:49:15 -0400 Message-Id: <1414154955-18114-1-git-send-email-aclements@csail.mit.edu> X-Mailer: git-send-email 2.1.0 In-Reply-To: References: X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrDIsWRmVeSWpSXmKPExsUixG6nonvZyyvE4Ot1OYum6c4W12/OZHZg 8rh1/zW7x7NVt5gDmKK4bFJSczLLUov07RK4MiatnsBacIavovvKdOYGxsvcXYycHBICJhLv N21hgbDFJC7cW8/WxcjFISQwm0li67rjUM5GRon5Ry4zQTh3mCQub7jDDuEsYZToWfkOrJ9N QF9ixdpJrCC2iIC0xM67s4FsDg5mATuJ3Y0BIGFhASeJK8/XMoHYLAKqEhfu72MDsXkF3CXO znrICnGGnMSG3f8ZQWxOgUCJb8vvgdUICQRIXPp3gXkCI/8CRoZVjLIpuVW6uYmZOcWpybrF yYl5ealFuiZ6uZkleqkppZsYQYHEKcm/g/HbQaVDjAIcjEo8vDdmeIYIsSaWFVfmHmKU5GBS EuVl8fQKEeJLyk+pzEgszogvKs1JLT7EKMHBrCTC62UClONNSaysSi3Kh0lJc7AoifNu+sEX IiSQnliSmp2aWpBaBJOV4eBQkuDNARkqWJSanlqRlplTgpBm4uAEGc4DNHwTSA1vcUFibnFm OkT+FKOilDjvCw+ghABIIqM0D64XFumvGMWBXhHmtQVp5wEmCbjuV0CDmYAGx2/wABlckoiQ kmpgXJh19PBKw00PhDr2n9wqvDPBv/hWo3JUQeeCFM/eQzXMWVNDtt8T+d+8VezCgbRwBa26 IzU3Zla61r5rbdtWdY3LVv53mKXj+upsZ3UJ+SeH92zh74nLdkx1by1jmO1uwD3H0/yc1eX6 7OrGDZP8F5t9WP+gI6Lx+hGmGY9kl/LLC2sXM8gosRRnJBpqMRcVJwIA1dA9i88CAAA= Cc: Austin Clements X-BeenThere: notmuch@notmuchmail.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: "Use and development of the notmuch mail system." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 24 Oct 2014 12:49:33 -0000 These macros help clarify basic bit-twiddling code and are written to be robust against C undefined behavior of shift operators. --- lib/message.cc | 6 +++--- lib/notmuch-private.h | 11 +++++++++++ 2 files changed, 14 insertions(+), 3 deletions(-) diff --git a/lib/message.cc b/lib/message.cc index 38bc929..55d2ff6 100644 --- a/lib/message.cc +++ b/lib/message.cc @@ -869,7 +869,7 @@ notmuch_bool_t notmuch_message_get_flag (notmuch_message_t *message, notmuch_message_flag_t flag) { - return message->flags & (1 << flag); + return NOTMUCH_TEST_BIT (message->flags, flag); } void @@ -877,9 +877,9 @@ notmuch_message_set_flag (notmuch_message_t *message, notmuch_message_flag_t flag, notmuch_bool_t enable) { if (enable) - message->flags |= (1 << flag); + NOTMUCH_SET_BIT (&message->flags, flag); else - message->flags &= ~(1 << flag); + NOTMUCH_CLEAR_BIT (&message->flags, flag); } time_t diff --git a/lib/notmuch-private.h b/lib/notmuch-private.h index 36cc12b..b86897c 100644 --- a/lib/notmuch-private.h +++ b/lib/notmuch-private.h @@ -63,6 +63,17 @@ NOTMUCH_BEGIN_DECLS #define STRNCMP_LITERAL(var, literal) \ strncmp ((var), (literal), sizeof (literal) - 1) +/* Robust bit test/set/reset macros */ +#define NOTMUCH_TEST_BIT(val, bit) \ + (((bit) < 0 || (bit) >= CHAR_BIT * sizeof (unsigned long long)) ? 0 \ + : !!((val) & (1ull << (bit)))) +#define NOTMUCH_SET_BIT(valp, bit) \ + (((bit) < 0 || (bit) >= CHAR_BIT * sizeof (unsigned long long)) ? *(valp) \ + : (*(valp) |= (1ull << (bit)))) +#define NOTMUCH_CLEAR_BIT(valp, bit) \ + (((bit) < 0 || (bit) >= CHAR_BIT * sizeof (unsigned long long)) ? *(valp) \ + : (*(valp) &= ~(1ull << (bit)))) + #define unused(x) x __attribute__ ((unused)) #ifdef __cplusplus -- 2.1.0