qemu-error: add {error, warn}_report_once_cond

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, which has been replaced
with warn_report_once_cond().

Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20180830145902.27376-2-cohuck@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Function comments reworded]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This commit is contained in:
Cornelia Huck
2018-08-30 16:59:01 +02:00
committed by Markus Armbruster
parent d6f71af654
commit c55510b722
3 changed files with 48 additions and 15 deletions

View File

@ -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);
bool error_report_once_cond(bool *printed, const char *fmt, ...)
GCC_FMT_ATTR(2, 3);
bool 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.