[ltt-dev] [BABELTRACE PATCH] Add parameters to callbacks

[Mathieu Desnoyers]

* Julien Desfossez (julien.desfossez at polymtl.ca) wrote:
> This patchs adds a new structure that is passed by the library as the
> first parameter of each callback call. As of now it only provides a
> pointer to the current event. Now we also pass the pointer to the
> private data registered when the callback is added.
> 
> Signed-off-by: Julien Desfossez <julien.desfossez at polymtl.ca>

Merged, thanks!

Mathieu

> ---
>  converter/babeltrace-lib.c      |   55 +++++++++++++++++++++++++++++++--------
>  include/babeltrace/babeltrace.h |    8 ++++-
>  2 files changed, 50 insertions(+), 13 deletions(-)
> 
> diff --git a/converter/babeltrace-lib.c b/converter/babeltrace-lib.c
> index 80c373f..a1dd64b 100644
> --- a/converter/babeltrace-lib.c
> +++ b/converter/babeltrace-lib.c
> @@ -56,7 +56,8 @@ struct bt_callback {
>  	struct bt_dependencies *depends;
>  	struct bt_dependencies *weak_depends;
>  	struct bt_dependencies *provides;
> -	enum bt_cb_ret (*callback)(void *private_data, void *caller_data);
> +	enum bt_cb_ret (*callback)(struct bt_ctf_data *ctf_data,
> +				   void *private_data);
>  };
>  
>  struct bt_callback_chain {
> @@ -138,7 +139,8 @@ struct bt_dependencies *babeltrace_dependencies_create(const char *first, ...)
>   */
>  int babeltrace_iter_add_callback(struct babeltrace_iter *iter,
>  		bt_event_name event, void *private_data, int flags,
> -		enum bt_cb_ret (*callback)(void *private_data, void *caller_data),
> +		enum bt_cb_ret (*callback)(struct bt_ctf_data *ctf_data,
> +					   void *private_data),
>  		struct bt_dependencies *depends,
>  		struct bt_dependencies *weak_depends,
>  		struct bt_dependencies *provides)
> @@ -426,7 +428,9 @@ void babeltrace_iter_destroy(struct babeltrace_iter *iter)
>  		for (j = 0; j < bt_stream_cb->per_id_callbacks->len; j++) {
>  			bt_chain = &g_array_index(bt_stream_cb->per_id_callbacks,
>  					struct bt_callback_chain, j);
> -			g_array_free(bt_chain->callback, TRUE);
> +			if (bt_chain->callback) {
> +				g_array_free(bt_chain->callback, TRUE);
> +			}
>  		}
>  		g_array_free(bt_stream_cb->per_id_callbacks, TRUE);
>  	}
> @@ -464,14 +468,43 @@ end:
>  }
>  
>  static
> +struct ctf_stream_event *extract_ctf_stream_event(struct ctf_stream *stream)
> +{
> +	struct ctf_stream_class *stream_class = stream->stream_class;
> +	struct ctf_event *event_class;
> +	struct ctf_stream_event *event;
> +	uint64_t id = stream->event_id;
> +
> +	if (id >= stream_class->events_by_id->len) {
> +		fprintf(stdout, "[error] Event id %" PRIu64 " is outside range.\n", id);
> +		return NULL;
> +	}
> +	event = g_ptr_array_index(stream->events_by_id, id);
> +	if (!event) {
> +		fprintf(stdout, "[error] Event id %" PRIu64 " is unknown.\n", id);
> +		return NULL;
> +	}
> +	event_class = g_ptr_array_index(stream_class->events_by_id, id);
> +	if (!event_class) {
> +		fprintf(stdout, "[error] Event id %" PRIu64 " is unknown.\n", id);
> +		return NULL;
> +	}
> +
> +	return event;
> +}
> +
> +static
>  void process_callbacks(struct babeltrace_iter *iter,
> -		struct ctf_stream *stream)
> +		       struct ctf_stream *stream)
>  {
>  	struct bt_stream_callbacks *bt_stream_cb;
>  	struct bt_callback_chain *bt_chain;
>  	struct bt_callback *cb;
>  	int i;
>  	enum bt_cb_ret ret;
> +	struct bt_ctf_data ctf_data;
> +
> +	ctf_data.event = extract_ctf_stream_event(stream);
>  
>  	/* process all events callback first */
>  	if (iter->main_callbacks.callback) {
> @@ -479,13 +512,13 @@ void process_callbacks(struct babeltrace_iter *iter,
>  			cb = &g_array_index(iter->main_callbacks.callback, struct bt_callback, i);
>  			if (!cb)
>  				goto end;
> -			ret = cb->callback(NULL, NULL);
> +			ret = cb->callback(&ctf_data, cb->private_data);
>  			switch (ret) {
> -				case BT_CB_OK_STOP:
> -				case BT_CB_ERROR_STOP:
> -					goto end;
> -				default:
> -					break;
> +			case BT_CB_OK_STOP:
> +			case BT_CB_ERROR_STOP:
> +				goto end;
> +			default:
> +				break;
>  			}
>  		}
>  	}
> @@ -507,7 +540,7 @@ void process_callbacks(struct babeltrace_iter *iter,
>  		cb = &g_array_index(bt_chain->callback, struct bt_callback, i);
>  		if (!cb)
>  			goto end;
> -		ret = cb->callback(NULL, NULL);
> +		ret = cb->callback(&ctf_data, cb->private_data);
>  		switch (ret) {
>  		case BT_CB_OK_STOP:
>  		case BT_CB_ERROR_STOP:
> diff --git a/include/babeltrace/babeltrace.h b/include/babeltrace/babeltrace.h
> index eb15de0..fe5881a 100644
> --- a/include/babeltrace/babeltrace.h
> +++ b/include/babeltrace/babeltrace.h
> @@ -50,6 +50,10 @@ struct trace_collection_pos {
>  	} u;
>  };
>  
> +struct bt_ctf_data {
> +	struct ctf_stream_event *event;
> +};
> +
>  /*
>   * babeltrace_iter_create - Allocate a trace collection iterator.
>   *
> @@ -162,8 +166,8 @@ void babeltrace_dependencies_destroy(struct bt_dependencies *dep);
>   */
>  int babeltrace_iter_add_callback(struct babeltrace_iter *iter,
>  		bt_event_name event, void *private_data, int flags,
> -		enum bt_cb_ret (*callback)(void *private_data,
> -					void *caller_data),
> +		enum bt_cb_ret (*callback)(struct bt_ctf_data *ctf_data,
> +					   void *caller_data),
>  		struct bt_dependencies *depends,
>  		struct bt_dependencies *weak_depends,
>  		struct bt_dependencies *provides);
> -- 
> 1.7.5.4
> 

-- 
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com