Re: [Qemu-devel] [PATCH v3 1/7] ui/cocoa: Ensure we have the iothread lock when calling into QEMU

[G 3 <programmingkidx@gmail.com>]

On Mon, Feb 25, 2019 at 5:24 AM Peter Maydell <peter.maydell@linaro.org>
wrote:

> The Cocoa UI should run on the main thread; this is enforced
> in OSX Mojave. In order to be able to run on the main thread,
> we need to make sure we hold the iothread lock whenever we
> call into various QEMU UI midlayer functions.
>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> Reviewed-by: Roman Bolshakov <r.bolshakv@yadro.com>
> Tested-by: Roman Bolshakov <r.bolshakov@yadro.com>
> Message-id: 20190214102816.3393-2-peter.maydell@linaro.org
> ---
> Changes since v2: add with_iothread_lock wrap to the
> qmp_stop()/qmp_cont() calls
> ---
>  ui/cocoa.m | 91 ++++++++++++++++++++++++++++++++++++++----------------
>  1 file changed, 65 insertions(+), 26 deletions(-)
>
> diff --git a/ui/cocoa.m b/ui/cocoa.m
> index e2567d6946..f1171c4865 100644
> --- a/ui/cocoa.m
> +++ b/ui/cocoa.m
> @@ -129,6 +129,21 @@
>  NSTextField *pauseLabel;
>  NSArray * supportedImageFileTypes;
>
> +// Utility function to run specified code block with iothread lock held
> +typedef void (^CodeBlock)(void);
>

Please don't use blocks. It would lock Mac OS X users into having to use
CLang. GCC does not support this non-standard extension.

C function pointers and Objective-C's selectors could work in place of
blocks.

Thank you.