1225928 - Speech dispatcher client hangs when spd_say is supplied with an empty string

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, defect)

Description

[Eitan Isaacson [:eeejay]]

When we supply an empty string to spd_say, it hangs and locks Firefox with the following JS:
speechSynthesis.speak(new SpeechSynthesisUtterance());

Comment 1

[Eitan Isaacson [:eeejay]]

Actually, nothing happens. But the queue is suspended, and if you call speechSynthesis.cancel() after the speak above, fx hangs.

Comment 2

[Eitan Isaacson [:eeejay]]

Attachment: Fix hang on linux when sending an empty string to speech synth.

Comment 3

[Olli Pettay [:smaug][[e-mail]]]

Comment on attachment 8689296 [details] [diff] [review]
Fix hang on linux when sending an empty string to speech synth.

I wonder if something here should happen async.
In fact, if I read the code correctly, we need to do that, since 
isn't mCurrentTask set _after_ Speak has been called (when nsSynthVoiceRegistry::GetInstance()->SpeakUtterance returns), but
then OnEnd has been called already and we're in an odd state then.

Or am I missing something here?

Comment 4

[Eitan Isaacson [:eeejay]]

(In reply to Olli Pettay [:smaug] from comment #3)
> Comment on attachment 8689296 [details] [diff] [review]
> Fix hang on linux when sending an empty string to speech synth.
> 
> I wonder if something here should happen async.
> In fact, if I read the code correctly, we need to do that, since 
> isn't mCurrentTask set _after_ Speak has been called (when
> nsSynthVoiceRegistry::GetInstance()->SpeakUtterance returns), but
> then OnEnd has been called already and we're in an odd state then.
> 
> Or am I missing something here?

This is true! It works fine in e10s since it is async anyway. I'll come up with another patch.

Comment 5

[Eitan Isaacson [:eeejay]]

Attachment: Fix hang on linux when sending an empty string to speech synth.

Emulate speechd events and make it asynchronous.

Comment 6

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/03c6bd7c9aec

Comment 7

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/03c6bd7c9aec