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 D5864431FB6 for ; Mon, 6 Oct 2014 16:17:34 -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 uLINbIqK3ONC for ; Mon, 6 Oct 2014 16:17:31 -0700 (PDT) Received: from dmz-mailsec-scanner-1.mit.edu (dmz-mailsec-scanner-1.mit.edu [18.9.25.12]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by olra.theworths.org (Postfix) with ESMTPS id F2914431FBC for ; Mon, 6 Oct 2014 16:17:26 -0700 (PDT) X-AuditID: 1209190c-f795e6d000006c66-10-543323062dd6 Received: from mailhub-auth-4.mit.edu ( [18.7.62.39]) (using TLS with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by dmz-mailsec-scanner-1.mit.edu (Symantec Messaging Gateway) with SMTP id 67.75.27750.60323345; Mon, 6 Oct 2014 19:17:26 -0400 (EDT) Received: from outgoing.mit.edu (outgoing-auth-1.mit.edu [18.9.28.11]) by mailhub-auth-4.mit.edu (8.13.8/8.9.2) with ESMTP id s96NHPeo032089; Mon, 6 Oct 2014 19:17:25 -0400 Received: from drake.dyndns.org ([12.185.136.2]) (authenticated bits=0) (User authenticated as amdragon@ATHENA.MIT.EDU) by outgoing.mit.edu (8.13.8/8.12.4) with ESMTP id s96NHMKE014465 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NOT); Mon, 6 Oct 2014 19:17:24 -0400 Received: from amthrax by drake.dyndns.org with local (Exim 4.84) (envelope-from ) id 1XbHWs-0001Jd-09; Mon, 06 Oct 2014 17:17:22 -0600 From: Austin Clements To: notmuch@notmuchmail.org Subject: [PATCH v2 06/12] lib: Introduce macros for bit operations Date: Mon, 6 Oct 2014 17:17:12 -0600 Message-Id: <1412637438-4821-7-git-send-email-aclements@csail.mit.edu> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1412637438-4821-1-git-send-email-aclements@csail.mit.edu> References: <1412637438-4821-1-git-send-email-aclements@csail.mit.edu> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrLIsWRmVeSWpSXmKPExsUixG6nrsumbBxisH0Vr8WN1m5Gi+s3ZzI7 MHk8W3WL2WPLoffMAUxRXDYpqTmZZalF+nYJXBkvF71kLdjFV9Gz+wJbA+NB7i5GTg4JAROJ 3R9OM0LYYhIX7q1nA7GFBGYzSTxpcOpi5AKyNzBKrNixnQXCWcok8WvlDnYIZwmjRHvrEWaQ FjYBfYkVayexgtgiAtISO+/OBrOZBRwk3k56CrZCWMBJ4t2xGSwgNouAqsTGZX1gcV4BN4kP LTfYIM6Qk9iw+z9YnFPAXWLNlcmsECe5STz/+ZRlAiP/AkaGVYyyKblVurmJmTnFqcm6xcmJ eXmpRbqGermZJXqpKaWbGEGhxCnJs4PxzUGlQ4wCHIxKPLwROwxDhFgTy4orcw8xSnIwKYny zmE3DhHiS8pPqcxILM6ILyrNSS0+xCjBwawkwsv12yhEiDclsbIqtSgfJiXNwaIkzrvpB1+I kEB6YklqdmpqQWoRTFaGg0NJgveQItBQwaLU9NSKtMycEoQ0EwcnyHAeoOFgNbzFBYm5xZnp EPlTjIpS4rzBIAkBkERGaR5cLyzWXzGKA70izHsTpIoHmCbgul8BDWYCGmw6Rx9kcEkiQkqq gXFOgcSOpFcK4XPuZBtX3C73jsjQ6Nfc1KNqMWm9rI2h1JwdgR0+iq5Z0/dO6axwyRCfLZ/t p93FVMJ7WcVv42XZ4vM8a/+y8km/9vv5LV7X5vKOkpf+E82vv5mXmLDv0gnusw6/hSOy2BRf bJtQLBC8Qqfqzd4T8x4tE7E+c3+3nOPet/PEdJVYijMSDbWYi4oTAU+HIQfQAgAA 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: Mon, 06 Oct 2014 23:17:35 -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..7250291 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