/* ppaml/tracer.h -- PPAML timing instrumentation interface
 * Copyright (C) 2013  Galois, Inc.
 *
 * This library is free software: you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation, either version 3 of the License, or (at your option)
 * any later version.
 *
 * This library is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this library.  If not, see <http://www.gnu.org/licenses/>.
 *
 * To contact Galois, complete the Web form at
 * <http://corp.galois.com/contact/> or write to Galois, Inc., 421 Southwest
 * 6th Avenue, Suite 300, Portland, Oregon, 97204-1622. */

/**
 * @file tracer.h
 * Library interface.
 *
 * This file defines the top-level interface for ppamltracer.
 *
 * Since all the functions in this file operate on @ref ppaml_tracer_t and @ref
 * ppaml_phase_t structs, their documentation has been moved to the relevant
 * data structure pages.
 */

#ifndef PPAML_TRACER_H
#define PPAML_TRACER_H

#include "tracer/internal.h"	// for ppaml_tracer_t and ppaml_phase_t

/**
 * @name Resource management
 *
 * @{
 */

/**
 * Initializes a ppaml_tracer_t.
 *
 * @relates ppaml_tracer_t
 *
 * The trace report will be stored in Open Trace Format; all trace file paths
 * will begin with @p report_name_base.
 *
 * @param[out] tracer pointer to the tracer to be initialized
 * @param[in] report_name_base base file name for the report files
 *
 * @pre @p tracer is nonnull.
 * @pre @p *tracer is uninitialized.
 *
 * @return 0 upon success
 * @return 1 if the Open Trace Format file manager could not be initialized
 * @return 2 if the Open Trace Format writer could not be initialized
 * @return 3 if setting the trace resolution failed
 * @return 4 if defining the main OTF process failed
 *
 * @post If the function return successfully, @p *tracer is initialized.
 */
int ppaml_tracer_init(ppaml_tracer_t *tracer, const char report_name_base[]);

/**
 * Finalizes a ppaml_tracer_t.
 *
 * @relates ppaml_tracer_t
 *
 * @param[out] tracer pointer to the tracer to be finalized
 *
 * @pre @p tracer is nonnull.
 * @pre @p *tracer is initialized.
 *
 * @return 0 upon success
 * @return 1 if the Open Trace Format writer could not be closed
 *
 * @post If the function return successfully, @p *tracer is uninitialized.
 */
int ppaml_tracer_done(ppaml_tracer_t *tracer);

/**
 * Initializes a ppaml_phase_t.
 *
 * @relates ppaml_phase_t
 *
 * @param[in] tracer pointer to the tracer which records this phase
 * @param[out] phase pointer to the phase to be initialized
 * @param[in] name name of the phase
 *
 * @pre @p tracer is nonnull.
 * @pre @p *tracer is initialized.
 * @pre @p phase is nonnull.
 * @pre @p *phase is uninitialized.
 *
 * @return 0 upon success
 * @return 1 if defining the phase failed
 *
 * @post If the function return successfully, @p *phase is initialized.
 */
int ppaml_phase_init(
	ppaml_tracer_t *tracer,
	ppaml_phase_t *phase,
	const char name[]);

/**
 * Finalizes a ppaml_phase_t.
 *
 * @relates ppaml_phase_t
 *
 * @param[out] phase pointer to the phase to be finalized
 *
 * @pre @p phase is nonnull.
 * @pre @p *phase is initialized.
 *
 * @return 0 upon success; a nonzero return indicates failure.
 *
 * @post If the function return successfully, @p *phase is uninitialized.
 */
int ppaml_phase_done(ppaml_phase_t *phase);

/// @}

/**
 * @name Timing
 *
 * @{
 */

/**
 * Records the start of a phase.
 *
 * @relates ppaml_phase_t
 *
 * @param[in] phase pointer to the phase
 *
 * @pre @p phase is nonnull.
 * @pre @p *phase is initialized.
 *
 * @return 0 upon success
 * @return 1 if getting the time failed
 * @return 2 if recording the phase start failed
 */
int ppaml_phase_start(ppaml_phase_t *phase);

/**
 * Records the end of a phase.
 *
 * @relates ppaml_phase_t
 *
 * @param[in] phase pointer to the phase
 *
 * @pre @p phase is nonnull.
 * @pre @p *phase is initialized.
 *
 * @return 0 upon success
 * @return 1 if getting the time failed
 * @return 2 if recording the phase stop failed
 */
int ppaml_phase_stop(ppaml_phase_t *phase);

/// @}

#endif