class Consumer

Called by Service (or more typically by the transport layer, on behalf of

the remote Service), once the Consumer

<

> Service connection has been

established.

Called by the Service or by the transport layer if the connection with the

service drops, either voluntarily (e.g., by destroying the ConsumerEndpoint

obtained through Service::ConnectConsumer()) or involuntarily (e.g., if the

Service process crashes).

Called by the Service after the tracing session has ended. This can happen

for a variety of reasons:

- The consumer explicitly called DisableTracing()

- The TraceConfig's |duration_ms| has been reached.

- The TraceConfig's |max_file_size_bytes| has been reached.

- An error occurred while trying to enable tracing. In this case |error|

is non-empty.

Called back by the Service (or transport layer) after invoking

TracingService::ConsumerEndpoint::ReadBuffers(). This function can be

called more than once. Each invocation can carry one or more

TracePacket(s). Upon the last call, |has_more| is set to false (i.e.

|has_more| is a !EOF).

Called back by the Service (or transport layer) after invoking

TracingService::ConsumerEndpoint::Detach().

The consumer can disconnect at this point and the trace session will keep

on going. A new consumer can later re-attach passing back the same |key|

passed to Detach(), but only if the two requests come from the same uid.

Called back by the Service (or transport layer) after invoking

TracingService::ConsumerEndpoint::Attach().

Called back by the Service (or transport layer) after invoking

TracingService::ConsumerEndpoint::GetTraceStats().

Called back by the Service (or transport layer) after invoking

TracingService::ConsumerEndpoint::ObserveEvents() whenever one or more

ObservableEvents of enabled event types occur.