From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33541) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fv30f-0003w4-TH for qemu-devel@nongnu.org; Wed, 29 Aug 2018 12:07:58 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fv30Z-0001DK-KF for qemu-devel@nongnu.org; Wed, 29 Aug 2018 12:07:57 -0400 From: Markus Armbruster References: <20180828123346.17548-1-cohuck@redhat.com> <20180828123346.17548-2-cohuck@redhat.com> Date: Wed, 29 Aug 2018 18:07:46 +0200 In-Reply-To: <20180828123346.17548-2-cohuck@redhat.com> (Cornelia Huck's message of "Tue, 28 Aug 2018 14:33:44 +0200") Message-ID: <87bm9l88bx.fsf@dusky.pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Qemu-devel] [PATCH 1/3] qemu-error: add {error, warn}_report_once_cond List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Cornelia Huck Cc: Markus Armbruster , Halil Pasic , qemu-s390x@nongnu.org, qemu-devel@nongnu.org, Peter Xu Cornelia Huck writes: > Add two functions to print an error/warning report once depending > on a passed-in condition variable and flip it if printed. This is > useful if you want to print a message not once-globally, but e.g. > once-per-device. > > Inspired by warn_once() in hw/vfio/ccw.c. This leaves the reader wondering why you don't replace that function. You do, in PATCH 3. I'd either announce that here, or squash the two patches. > > Signed-off-by: Cornelia Huck > --- > include/qemu/error-report.h | 5 +++++ > util/qemu-error.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 49 insertions(+) > > diff --git a/include/qemu/error-report.h b/include/qemu/error-report.h > index 72fab2b031..d2a6515e68 100644 > --- a/include/qemu/error-report.h > +++ b/include/qemu/error-report.h > @@ -44,6 +44,11 @@ void error_report(const char *fmt, ...) GCC_FMT_ATTR(1, 2); > void warn_report(const char *fmt, ...) GCC_FMT_ATTR(1, 2); > void info_report(const char *fmt, ...) GCC_FMT_ATTR(1, 2); > > +void error_report_once_cond(bool *printed, const char *fmt, ...) > + GCC_FMT_ATTR(2, 3); > +void warn_report_once_cond(bool *printed, const char *fmt, ...) > + GCC_FMT_ATTR(2, 3); > + > /* > * Similar to error_report(), except it prints the message just once. > * Return true when it prints, false otherwise. > diff --git a/util/qemu-error.c b/util/qemu-error.c > index a25d3b94c6..0894ab6995 100644 > --- a/util/qemu-error.c > +++ b/util/qemu-error.c > @@ -310,3 +310,47 @@ void info_report(const char *fmt, ...) > vreport(REPORT_TYPE_INFO, fmt, ap); > va_end(ap); > } > + > +/* > + * If *printed is false, print an error message to current monitor if we > + * have one, else to stderr, and flip *printed to true. > + * If printed is NULL, do not print anything. Any particular reason for supporting null @printed? For what it's worth, warn_once() supports it, but its caller doesn't use it. > + * Format arguments like sprintf(). The resulting message should be > + * a single phrase, with no newline or trailing punctuation. > + * Prepend the current location and append a newline. > + * It's wrong to call this in a QMP monitor. Use error_setg() there. > + */ > +void error_report_once_cond(bool *printed, const char *fmt, ...) > +{ > + va_list ap; > + > + if (!printed || *printed) { > + return; > + } > + *printed = true; > + va_start(ap, fmt); > + vreport(REPORT_TYPE_ERROR, fmt, ap); > + va_end(ap); > +} > + > +/* > + * If *printed is false, print a warning message to current monitor if we > + * have one, else to stderr, and flip *printed to true. > + * If printed is NULL, do not print anything. > + * Format arguments like sprintf(). The resulting message should be > + * a single phrase, with no newline or trailing punctuation. > + * Prepend the current location and append a newline. > + * It's wrong to call this in a QMP monitor. Use error_setg() there. > + */ > +void warn_report_once_cond(bool *printed, const char *fmt, ...) > +{ > + va_list ap; > + > + if (!printed || *printed) { > + return; > + } > + *printed = true; > + va_start(ap, fmt); > + vreport(REPORT_TYPE_WARNING, fmt, ap); > + va_end(ap); > +}