Daniel P. Berrangé <[email protected]> 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 <[email protected]> > Signed-off-by: Daniel P. Berrangé <[email protected]> > --- > 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 <[email protected]> > 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 = (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 = flags; > +} > + > +void qmessage_context_print(FILE *fp) > +{ > + if (message_format & QMESSAGE_FORMAT_TIMESTAMP) { > + g_autoptr(GDateTime) dt = g_date_time_new_now_utc(); > + g_autofree char *timestr = 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?
