Adding a test which do a sequence of seek BEGIN, LAST, BEGIN, LAST

[babeltrace.git] / include / babeltrace / ctf / callbacks.h

#ifndef _BABELTRACE_CTF_CALLBACKS_H
#define _BABELTRACE_CTF_CALLBACKS_H

/*
 * BabelTrace
 *
 * CTF events API
 *
 * Copyright 2011-2012 EfficiOS Inc. and Linux Foundation
 *
 * Author: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *         Julien Desfossez <julien.desfossez@efficios.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 */

#include <babeltrace/format.h>

#ifdef __cplusplus
extern "C" {
#endif

/* Forward declarations */
struct bt_ctf_iter;
struct bt_dependencies;

enum bt_cb_ret {
	BT_CB_OK		= 0,
	BT_CB_OK_STOP		= 1,
	BT_CB_ERROR_STOP	= 2,
	BT_CB_ERROR_CONTINUE	= 3,
};

/*
 * Receives a variable number of strings as parameter, ended with NULL.
 */
struct bt_dependencies *babeltrace_dependencies_create(const char *first, ...);

/*
 * struct bt_dependencies must be destroyed explicitly if not passed as
 * parameter to a bt_ctf_iter_add_callback().
 */
void babeltrace_dependencies_destroy(struct bt_dependencies *dep);

/*
 * bt_ctf_iter_add_callback: Add a callback to iterator.
 *
 * @iter: trace collection iterator (input)
 * @event: event to target. 0 for all events.
 * @private_data: private data pointer to pass to the callback
 * @flags: specific flags controlling the behavior of this callback
 *         (or'd).
 *            
 * @callback: function pointer to call
 * @depends: struct bt_dependency detailing the required computation results.
 *           Ends with 0. NULL is accepted as empty dependency.
 * @weak_depends: struct bt_dependency detailing the optional computation
 *                results that can be optionally consumed by this
 *                callback. NULL is accepted as empty dependency.
 * @provides: struct bt_dependency detailing the computation results
 *            provided by this callback.
 *            Ends with 0. NULL is accepted as empty dependency.
 *
 * "depends", "weak_depends" and "provides" memory is handled by the
 * babeltrace library after this call succeeds or fails. These objects
 * can still be used by the caller until the babeltrace iterator is
 * destroyed, but they belong to the babeltrace library.
 *
 * (note to implementor: we need to keep a gptrarray of struct
 * bt_dependencies to "garbage collect" in struct bt_ctf_iter, and
 * dependencies need to have a refcount to handle the case where they
 * would be passed to more than one iterator. Upon iterator detroy, we
 * iterate on all the gc ptrarray and decrement the refcounts, freeing
 * if we reach 0.)
 * (note to implementor: we calculate the dependency graph when
 * bt_ctf_iter_read_event() is executed after a
 * bt_ctf_iter_add_callback(). Beware that it is valid to create/add
 * callbacks/read/add more callbacks/read some more.)
 */
int bt_ctf_iter_add_callback(struct bt_ctf_iter *iter,
		bt_intern_str event, void *private_data, int flags,
		enum bt_cb_ret (*callback)(struct bt_ctf_event *ctf_data,
					   void *caller_data),
		struct bt_dependencies *depends,
		struct bt_dependencies *weak_depends,
		struct bt_dependencies *provides);

/*
 * For flags parameter above.
 */
enum {
	BT_FLAGS_FREE_PRIVATE_DATA	= (1 << 0),
};

#ifdef __cplusplus
}
#endif

#endif /*_BABELTRACE_CTF_CALLBACKS_H */