Thanks! I got it to work. Here is what I did, let me know if this correct.
struct Baton {
Persistent<Function> callback;
int error;
std::string error_message;
uv_async_t async;
// Custom data
Persistent<Object> data;
};
JS_METHOD(Event::setCallback) {
Baton *baton=new Baton();
baton->callback=Persistent<Function>::New(Local<Function>::Cast(args[0]));
uv_async_init(uv_default_loop(), &baton->async, After_cb); // tell UV to
call After_cb() async
baton->async.data=baton;
call_driver(..., driver_cb, baton);
}
void driver_cb (int status, void *user_data)
{
...
uv_async_send(((Baton*) user_data)->async); // wakes up UV to call
After_cb()
}
void After_cb(uv_async_t *handle, int status) {
Baton *baton = static_cast<Baton*>(handle->data);
uv_close((uv_handle_t*) &baton->async,NULL); // necessary otherwise UV
will block
...
baton->callback->Call(v8::Context::GetCurrent()->Global(), 1, argv); //
call the JS callback method as usual
...
baton->callback.Dispose(); // delete the baton
baton->data.Dispose();
delete baton;
}
On Friday, March 16, 2012 10:48:42 AM UTC-7, Nathan Rajlich wrote:
>
> I'm pretty sure this is what uv_async_t, uv_async_send and friends are
> for, but somebody correct be if I am wrong.
>
> On Fri, Mar 16, 2012 at 10:22 AM, m1k3l <mikese...@gmail.com> wrote:
>
>> Hi,
>>
>> I have a native method running in its own thread and calling a callback
>> to post its status. The callback has some user data that I'd like to post
>> to JS.
>> Since the callback is running in a different thread than v8, I can't use
>> any v8 method to call a JS callback function. So I wonder if there is a way
>> to use some persistent objects to do that?
>>
>> One solution I found is to use queue the native method using libuv. This
>> way, I can use a busy wait in uv's Work callback method until my native
>> method's callback is called. Then uv's Work callback proceed and I can use
>> uv's After callback to call the JS callback method, as usual.
>>
>> While this seems to work, it still looks like very hack-ish. Is there a
>> better solution/pattern?
>>
>> Thanks
>>
>
>
On Friday, March 16, 2012 10:48:42 AM UTC-7, Nathan Rajlich wrote:
>
> I'm pretty sure this is what uv_async_t, uv_async_send and friends are
> for, but somebody correct be if I am wrong.
>
> On Fri, Mar 16, 2012 at 10:22 AM, m1k3l <mikese...@gmail.com> wrote:
>
>> Hi,
>>
>> I have a native method running in its own thread and calling a callback
>> to post its status. The callback has some user data that I'd like to post
>> to JS.
>> Since the callback is running in a different thread than v8, I can't use
>> any v8 method to call a JS callback function. So I wonder if there is a way
>> to use some persistent objects to do that?
>>
>> One solution I found is to use queue the native method using libuv. This
>> way, I can use a busy wait in uv's Work callback method until my native
>> method's callback is called. Then uv's Work callback proceed and I can use
>> uv's After callback to call the JS callback method, as usual.
>>
>> While this seems to work, it still looks like very hack-ish. Is there a
>> better solution/pattern?
>>
>> Thanks
>>
>
>
