From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34286) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dbRXR-0005Hq-2q for qemu-devel@nongnu.org; Sat, 29 Jul 2017 09:12:14 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dbRXN-00067Q-Qp for qemu-devel@nongnu.org; Sat, 29 Jul 2017 09:12:13 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:45660 helo=relay.sw.ru) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dbRXN-00062f-Fc for qemu-devel@nongnu.org; Sat, 29 Jul 2017 09:12:09 -0400 From: Vladimir Sementsov-Ogievskiy Date: Sat, 29 Jul 2017 16:11:56 +0300 Message-Id: <20170729131159.24949-2-vsementsov@virtuozzo.com> In-Reply-To: <20170729131159.24949-1-vsementsov@virtuozzo.com> References: <20170729131159.24949-1-vsementsov@virtuozzo.com> Subject: [Qemu-devel] [PATCH v2 1/4] coding_style: add point about 0x in trace-events List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: pbonzini@redhat.com, eblake@redhat.com, mreitz@redhat.com, jsnow@redhat.com, vsementsov@virtuozzo.com, den@openvz.org, stefanha@gmail.com, peter.maydell@linaro.org, berrange@redhat.com Signed-off-by: Vladimir Sementsov-Ogievskiy --- CODING_STYLE | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/CODING_STYLE b/CODING_STYLE index 2fa0c0b65b..2e6a0507be 100644 --- a/CODING_STYLE +++ b/CODING_STYLE @@ -123,3 +123,26 @@ We use traditional C-style /* */ comments and avoid // comments. Rationale: The // form is valid in C99, so this is purely a matter of consistency of style. The checkpatch script will warn you about this. + +8. trace-events style + +In trace-events files use '0x' prefix to specify hex numbers, as in: + +some_trace(unsigned x, uint64_t y) "x 0x%x y 0x" PRIx64 + +The exclusion is a group of numbers, separated by symbols '.', '/', ':', ' ': + +some_other_trace(unsigned a, unsigned b, unsigned c) "num %x.%x.%x" + +However, you can use '0x' for such groups if you want. Anyway, be sure that +it is obvious that numbers are in hex, ex.: + +data_dump(uint8_t c1, uint8_t c2, uint8_t c3) "bytes (in hex): %02x %02x %02x" + +For consistency do not use printf flag '#', like '%#x'. + +Rationale: hex numbers are hard to read in logs when there no 0x prefix, +especially when (occasionally) the representation doesn't contain any letters +and especially in one line with other decimal numbers. Number groups are +allowed to not use '0x' because for some things notations like %x.%x.%x are +used not only in Qemu. Also dumping raw data bytes with '0x' is less readable. -- 2.11.1