From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7E361E9A02C for ; Wed, 18 Feb 2026 14:07:16 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vsiAS-000706-Do; Wed, 18 Feb 2026 09:04:45 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vsiAN-0006zc-LL for qemu-rust@nongnu.org; Wed, 18 Feb 2026 09:04:35 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vsiAL-0007cc-Tm for qemu-rust@nongnu.org; Wed, 18 Feb 2026 09:04:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1771423472; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3FLojfTLE4eLm/XXjE3D7lXFlW7GaXopO/nuhESGVJg=; b=SffAwLOO37/f7kVRJ96Y8qmtpUID/AjytNcBXOsEbglz04gcEX4KvVmb7Tim4AZ46QMw3T drO2I7tqawqm6IFBDeT2TqpJcYARnp3WD56YuQ9uc8/WzC1qbqTExcTVNzt85nkLFSzpyU gHSpFn9gHSXG2krLjd2xjYXm8P6hRiw= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-176-YXjKa5LFN8i2DxQauVFtYw-1; Wed, 18 Feb 2026 09:04:28 -0500 X-MC-Unique: YXjKa5LFN8i2DxQauVFtYw-1 X-Mimecast-MFC-AGG-ID: YXjKa5LFN8i2DxQauVFtYw_1771423467 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id D4FD21800342; Wed, 18 Feb 2026 14:04:26 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.45.242.14]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 206611800370; Wed, 18 Feb 2026 14:04:26 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id B927721E692D; Wed, 18 Feb 2026 15:04:23 +0100 (CET) From: Markus Armbruster To: Daniel P. =?utf-8?Q?Berrang=C3=A9?= Cc: qemu-devel@nongnu.org, Manos Pitsidianakis , Stefan Weil , "Dr. David Alan Gilbert" , Pierrick Bouvier , devel@lists.libvirt.org, Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , =?utf-8?Q?Marc-Andr?= =?utf-8?Q?=C3=A9?= Lureau , Hanna Reitz , Kevin Wolf , qemu-block@nongnu.org, qemu-rust@nongnu.org, Paolo Bonzini , Gerd Hoffmann , Christian Schoenebeck , Richard Henderson Subject: Re: [PATCH v6 22/27] util: introduce common helper for error-report & log code In-Reply-To: <20260211152508.732487-23-berrange@redhat.com> ("Daniel P. =?utf-8?Q?Berrang=C3=A9=22's?= message of "Wed, 11 Feb 2026 15:25:03 +0000") References: <20260211152508.732487-1-berrange@redhat.com> <20260211152508.732487-23-berrange@redhat.com> Date: Wed, 18 Feb 2026 15:04:23 +0100 Message-ID: <87342yb120.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 X-Mimecast-MFC-PROC-ID: -QlVg04Y7AElKaaq5rkJy3sOTgjJZyfjoxTL43Up4jg_1771423467 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -13 X-Spam_score: -1.4 X-Spam_bar: - X-Spam_report: (-1.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.043, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, GB_FAKE_RF=0.754, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-rust@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: QEMU Rust-related patches and discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-rust-bounces+qemu-rust=archiver.kernel.org@nongnu.org Sender: qemu-rust-bounces+qemu-rust=archiver.kernel.org@nongnu.org Daniel P. Berrang=C3=A9 writes: > The error-report and log code both have a need to add prefixes > to messages they are printing, with the current example being > a timestamp. > > The format and configuration they use should be consistent, so > providing a common helper will ensure this is always the case. > Initially the helper only emits a timestamp, but future patches > will expand this. > > This takes the liberty of assigning the new file to the same > maintainer as the existing error-report.c file, given it will > be extracting some functionality from the latter. Fair. > While vreport() dynamically changes between reporting to the > monitor vs stderr, depending on whether HMP is active or not, > message prefixes are only ever used in the non-HMP case. Thus > the helper API can take a FILE * object and not have to deal > with the monitor at all. > > Reviewed-by: Richard Henderson > Signed-off-by: Daniel P. Berrang=C3=A9 > --- > MAINTAINERS | 2 ++ > include/qemu/message.h | 28 ++++++++++++++++++++++++++++ > util/meson.build | 1 + > util/message.c | 23 +++++++++++++++++++++++ > 4 files changed, 54 insertions(+) > create mode 100644 include/qemu/message.h > create mode 100644 util/message.c No uses, yet. Commit message could mention it's put to use in the next few commits. > > diff --git a/MAINTAINERS b/MAINTAINERS > index 29f88d48f3..96a4ce438e 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -3261,9 +3261,11 @@ M: Markus Armbruster > S: Supported > F: include/qapi/error.h > F: include/qemu/error-report.h > +F: include/qemu/message.h > F: qapi/error.json > F: util/error.c > F: util/error-report.c > +F: util/message.c > F: scripts/coccinelle/err-bad-newline.cocci > F: scripts/coccinelle/error-use-after-free.cocci > F: scripts/coccinelle/error_propagate_null.cocci > diff --git a/include/qemu/message.h b/include/qemu/message.h > new file mode 100644 > index 0000000000..0a06421f77 > --- /dev/null > +++ b/include/qemu/message.h > @@ -0,0 +1,28 @@ > +/* SPDX-License-Identifier: GPL-2.0-or-later */ > + > +#ifndef QEMU_MESSAGE_H > +#define QEMU_MESSAGE_H > + > +enum QMessageFormatFlags { > + QMESSAGE_FORMAT_TIMESTAMP =3D (1 << 0), > +}; > + > +/** > + * qmessage_set_format: > + * @flags: the message information to emit > + * > + * Select which pieces of information to > + * emit for messages > + */ > +void qmessage_set_format(int flags); > + > +/** > + * qmessage_context_print: > + * @fp: file to emit the prefix on > + * > + * Emit a message prefix with the information selected by > + * an earlier call to qmessage_set_format. > + */ > +void qmessage_context_print(FILE *fp); > + > +#endif /* QEMU_MESSAGE_H */ > diff --git a/util/meson.build b/util/meson.build > index 7c9445615d..3035bd4bee 100644 > --- a/util/meson.build > +++ b/util/meson.build > @@ -38,6 +38,7 @@ util_ss.add(files('host-utils.c')) > util_ss.add(files('bitmap.c', 'bitops.c')) > util_ss.add(files('fifo8.c')) > util_ss.add(files('cacheflush.c')) > +util_ss.add(files('message.c')) > util_ss.add(files('error.c', 'error-report.c')) > util_ss.add(files('qemu-print.c')) > util_ss.add(files('id.c')) > diff --git a/util/message.c b/util/message.c > new file mode 100644 > index 0000000000..99a403f9d0 > --- /dev/null > +++ b/util/message.c > @@ -0,0 +1,23 @@ > +/* SPDX-License-Identifier: GPL-2.0-or-later */ > + > +#include "qemu/osdep.h" > + > +#include "qemu/message.h" > +#include "monitor/monitor.h" Superfluous #include. It'll become used in PATCH 26, for qemu_thread_get_name(). Should include qemu/thread.h there instead. > + > +static int message_format; > + > +void qmessage_set_format(int flags) > +{ > + message_format =3D flags; > +} > + > +void qmessage_context_print(FILE *fp) > +{ > + if (message_format & QMESSAGE_FORMAT_TIMESTAMP) { > + g_autoptr(GDateTime) dt =3D g_date_time_new_now_utc(); > + g_autofree char *timestr =3D g_date_time_format_iso8601(dt); > + fputs(timestr, fp); > + fputc(' ', fp); The context string is either empty, or it ends with a space, for ease of use. Okay. I'd go for fprintf(fp, "%s ", timestr); > + } > +} Alright, everybody's favorite topic: naming. message.[ch] aren't about messages, but message *prefixes*. You call them "context" in qmessage_context_print(). I'm fine with "context". External symbols are prefixed with qmessage_. I prefer such prefixes to match the filename. Prefix in util/ overwhelmingly start with qemu_. Somewhat long prefixes feel okay here, as these symbols are used only a couple of times. qemu_message_context_ might be too long, though. Could use the classic technique of murdering vowels: to qemu_msg_ctxt_. Thoughts?